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1 /*
2  * Copyright © 2010 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21  * DEALINGS IN THE SOFTWARE.
22  */
23 
24 /**
25  * \file ast_to_hir.c
26  * Convert abstract syntax to to high-level intermediate reprensentation (HIR).
27  *
28  * During the conversion to HIR, the majority of the symantic checking is
29  * preformed on the program.  This includes:
30  *
31  *    * Symbol table management
32  *    * Type checking
33  *    * Function binding
34  *
35  * The majority of this work could be done during parsing, and the parser could
36  * probably generate HIR directly.  However, this results in frequent changes
37  * to the parser code.  Since we do not assume that every system this complier
38  * is built on will have Flex and Bison installed, we have to store the code
39  * generated by these tools in our version control system.  In other parts of
40  * the system we've seen problems where a parser was changed but the generated
41  * code was not committed, merge conflicts where created because two developers
42  * had slightly different versions of Bison installed, etc.
43  *
44  * I have also noticed that running Bison generated parsers in GDB is very
45  * irritating.  When you get a segfault on '$$ = $1->foo', you can't very
46  * well 'print $1' in GDB.
47  *
48  * As a result, my preference is to put as little C code as possible in the
49  * parser (and lexer) sources.
50  */
51 
52 #include "glsl_symbol_table.h"
53 #include "glsl_parser_extras.h"
54 #include "ast.h"
55 #include "compiler/glsl_types.h"
56 #include "util/hash_table.h"
57 #include "main/macros.h"
58 #include "main/shaderobj.h"
59 #include "ir.h"
60 #include "ir_builder.h"
61 #include "builtin_functions.h"
62 
63 using namespace ir_builder;
64 
65 static void
66 detect_conflicting_assignments(struct _mesa_glsl_parse_state *state,
67                                exec_list *instructions);
68 static void
69 remove_per_vertex_blocks(exec_list *instructions,
70                          _mesa_glsl_parse_state *state, ir_variable_mode mode);
71 
72 /**
73  * Visitor class that finds the first instance of any write-only variable that
74  * is ever read, if any
75  */
76 class read_from_write_only_variable_visitor : public ir_hierarchical_visitor
77 {
78 public:
read_from_write_only_variable_visitor()79    read_from_write_only_variable_visitor() : found(NULL)
80    {
81    }
82 
visit(ir_dereference_variable * ir)83    virtual ir_visitor_status visit(ir_dereference_variable *ir)
84    {
85       if (this->in_assignee)
86          return visit_continue;
87 
88       ir_variable *var = ir->variable_referenced();
89       /* We can have memory_write_only set on both images and buffer variables,
90        * but in the former there is a distinction between reads from
91        * the variable itself (write_only) and from the memory they point to
92        * (memory_write_only), while in the case of buffer variables there is
93        * no such distinction, that is why this check here is limited to
94        * buffer variables alone.
95        */
96       if (!var || var->data.mode != ir_var_shader_storage)
97          return visit_continue;
98 
99       if (var->data.memory_write_only) {
100          found = var;
101          return visit_stop;
102       }
103 
104       return visit_continue;
105    }
106 
get_variable()107    ir_variable *get_variable() {
108       return found;
109    }
110 
visit_enter(ir_expression * ir)111    virtual ir_visitor_status visit_enter(ir_expression *ir)
112    {
113       /* .length() doesn't actually read anything */
114       if (ir->operation == ir_unop_ssbo_unsized_array_length)
115          return visit_continue_with_parent;
116 
117       return visit_continue;
118    }
119 
120 private:
121    ir_variable *found;
122 };
123 
124 void
_mesa_ast_to_hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)125 _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state)
126 {
127    _mesa_glsl_initialize_variables(instructions, state);
128 
129    state->symbols->separate_function_namespace = state->language_version == 110;
130 
131    state->current_function = NULL;
132 
133    state->toplevel_ir = instructions;
134 
135    state->gs_input_prim_type_specified = false;
136    state->tcs_output_vertices_specified = false;
137    state->cs_input_local_size_specified = false;
138 
139    /* Section 4.2 of the GLSL 1.20 specification states:
140     * "The built-in functions are scoped in a scope outside the global scope
141     *  users declare global variables in.  That is, a shader's global scope,
142     *  available for user-defined functions and global variables, is nested
143     *  inside the scope containing the built-in functions."
144     *
145     * Since built-in functions like ftransform() access built-in variables,
146     * it follows that those must be in the outer scope as well.
147     *
148     * We push scope here to create this nesting effect...but don't pop.
149     * This way, a shader's globals are still in the symbol table for use
150     * by the linker.
151     */
152    state->symbols->push_scope();
153 
154    foreach_list_typed (ast_node, ast, link, & state->translation_unit)
155       ast->hir(instructions, state);
156 
157    detect_recursion_unlinked(state, instructions);
158    detect_conflicting_assignments(state, instructions);
159 
160    state->toplevel_ir = NULL;
161 
162    /* Move all of the variable declarations to the front of the IR list, and
163     * reverse the order.  This has the (intended!) side effect that vertex
164     * shader inputs and fragment shader outputs will appear in the IR in the
165     * same order that they appeared in the shader code.  This results in the
166     * locations being assigned in the declared order.  Many (arguably buggy)
167     * applications depend on this behavior, and it matches what nearly all
168     * other drivers do.
169     */
170    foreach_in_list_safe(ir_instruction, node, instructions) {
171       ir_variable *const var = node->as_variable();
172 
173       if (var == NULL)
174          continue;
175 
176       var->remove();
177       instructions->push_head(var);
178    }
179 
180    /* Figure out if gl_FragCoord is actually used in fragment shader */
181    ir_variable *const var = state->symbols->get_variable("gl_FragCoord");
182    if (var != NULL)
183       state->fs_uses_gl_fragcoord = var->data.used;
184 
185    /* From section 7.1 (Built-In Language Variables) of the GLSL 4.10 spec:
186     *
187     *     If multiple shaders using members of a built-in block belonging to
188     *     the same interface are linked together in the same program, they
189     *     must all redeclare the built-in block in the same way, as described
190     *     in section 4.3.7 "Interface Blocks" for interface block matching, or
191     *     a link error will result.
192     *
193     * The phrase "using members of a built-in block" implies that if two
194     * shaders are linked together and one of them *does not use* any members
195     * of the built-in block, then that shader does not need to have a matching
196     * redeclaration of the built-in block.
197     *
198     * This appears to be a clarification to the behaviour established for
199     * gl_PerVertex by GLSL 1.50, therefore implement it regardless of GLSL
200     * version.
201     *
202     * The definition of "interface" in section 4.3.7 that applies here is as
203     * follows:
204     *
205     *     The boundary between adjacent programmable pipeline stages: This
206     *     spans all the outputs in all compilation units of the first stage
207     *     and all the inputs in all compilation units of the second stage.
208     *
209     * Therefore this rule applies to both inter- and intra-stage linking.
210     *
211     * The easiest way to implement this is to check whether the shader uses
212     * gl_PerVertex right after ast-to-ir conversion, and if it doesn't, simply
213     * remove all the relevant variable declaration from the IR, so that the
214     * linker won't see them and complain about mismatches.
215     */
216    remove_per_vertex_blocks(instructions, state, ir_var_shader_in);
217    remove_per_vertex_blocks(instructions, state, ir_var_shader_out);
218 
219    /* Check that we don't have reads from write-only variables */
220    read_from_write_only_variable_visitor v;
221    v.run(instructions);
222    ir_variable *error_var = v.get_variable();
223    if (error_var) {
224       /* It would be nice to have proper location information, but for that
225        * we would need to check this as we process each kind of AST node
226        */
227       YYLTYPE loc;
228       memset(&loc, 0, sizeof(loc));
229       _mesa_glsl_error(&loc, state, "Read from write-only variable `%s'",
230                        error_var->name);
231    }
232 }
233 
234 
235 static ir_expression_operation
get_implicit_conversion_operation(const glsl_type * to,const glsl_type * from,struct _mesa_glsl_parse_state * state)236 get_implicit_conversion_operation(const glsl_type *to, const glsl_type *from,
237                                   struct _mesa_glsl_parse_state *state)
238 {
239    switch (to->base_type) {
240    case GLSL_TYPE_FLOAT:
241       switch (from->base_type) {
242       case GLSL_TYPE_INT: return ir_unop_i2f;
243       case GLSL_TYPE_UINT: return ir_unop_u2f;
244       default: return (ir_expression_operation)0;
245       }
246 
247    case GLSL_TYPE_UINT:
248       if (!state->is_version(400, 0) && !state->ARB_gpu_shader5_enable
249           && !state->MESA_shader_integer_functions_enable)
250          return (ir_expression_operation)0;
251       switch (from->base_type) {
252          case GLSL_TYPE_INT: return ir_unop_i2u;
253          default: return (ir_expression_operation)0;
254       }
255 
256    case GLSL_TYPE_DOUBLE:
257       if (!state->has_double())
258          return (ir_expression_operation)0;
259       switch (from->base_type) {
260       case GLSL_TYPE_INT: return ir_unop_i2d;
261       case GLSL_TYPE_UINT: return ir_unop_u2d;
262       case GLSL_TYPE_FLOAT: return ir_unop_f2d;
263       case GLSL_TYPE_INT64: return ir_unop_i642d;
264       case GLSL_TYPE_UINT64: return ir_unop_u642d;
265       default: return (ir_expression_operation)0;
266       }
267 
268    case GLSL_TYPE_UINT64:
269       if (!state->has_int64())
270          return (ir_expression_operation)0;
271       switch (from->base_type) {
272       case GLSL_TYPE_INT: return ir_unop_i2u64;
273       case GLSL_TYPE_UINT: return ir_unop_u2u64;
274       case GLSL_TYPE_INT64: return ir_unop_i642u64;
275       default: return (ir_expression_operation)0;
276       }
277 
278    case GLSL_TYPE_INT64:
279       if (!state->has_int64())
280          return (ir_expression_operation)0;
281       switch (from->base_type) {
282       case GLSL_TYPE_INT: return ir_unop_i2i64;
283       default: return (ir_expression_operation)0;
284       }
285 
286    default: return (ir_expression_operation)0;
287    }
288 }
289 
290 
291 /**
292  * If a conversion is available, convert one operand to a different type
293  *
294  * The \c from \c ir_rvalue is converted "in place".
295  *
296  * \param to     Type that the operand it to be converted to
297  * \param from   Operand that is being converted
298  * \param state  GLSL compiler state
299  *
300  * \return
301  * If a conversion is possible (or unnecessary), \c true is returned.
302  * Otherwise \c false is returned.
303  */
304 static bool
apply_implicit_conversion(const glsl_type * to,ir_rvalue * & from,struct _mesa_glsl_parse_state * state)305 apply_implicit_conversion(const glsl_type *to, ir_rvalue * &from,
306                           struct _mesa_glsl_parse_state *state)
307 {
308    void *ctx = state;
309    if (to->base_type == from->type->base_type)
310       return true;
311 
312    /* Prior to GLSL 1.20, there are no implicit conversions */
313    if (!state->is_version(120, 0))
314       return false;
315 
316    /* ESSL does not allow implicit conversions */
317    if (state->es_shader)
318       return false;
319 
320    /* From page 27 (page 33 of the PDF) of the GLSL 1.50 spec:
321     *
322     *    "There are no implicit array or structure conversions. For
323     *    example, an array of int cannot be implicitly converted to an
324     *    array of float.
325     */
326    if (!to->is_numeric() || !from->type->is_numeric())
327       return false;
328 
329    /* We don't actually want the specific type `to`, we want a type
330     * with the same base type as `to`, but the same vector width as
331     * `from`.
332     */
333    to = glsl_type::get_instance(to->base_type, from->type->vector_elements,
334                                 from->type->matrix_columns);
335 
336    ir_expression_operation op = get_implicit_conversion_operation(to, from->type, state);
337    if (op) {
338       from = new(ctx) ir_expression(op, to, from, NULL);
339       return true;
340    } else {
341       return false;
342    }
343 }
344 
345 
346 static const struct glsl_type *
arithmetic_result_type(ir_rvalue * & value_a,ir_rvalue * & value_b,bool multiply,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)347 arithmetic_result_type(ir_rvalue * &value_a, ir_rvalue * &value_b,
348                        bool multiply,
349                        struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
350 {
351    const glsl_type *type_a = value_a->type;
352    const glsl_type *type_b = value_b->type;
353 
354    /* From GLSL 1.50 spec, page 56:
355     *
356     *    "The arithmetic binary operators add (+), subtract (-),
357     *    multiply (*), and divide (/) operate on integer and
358     *    floating-point scalars, vectors, and matrices."
359     */
360    if (!type_a->is_numeric() || !type_b->is_numeric()) {
361       _mesa_glsl_error(loc, state,
362                        "operands to arithmetic operators must be numeric");
363       return glsl_type::error_type;
364    }
365 
366 
367    /*    "If one operand is floating-point based and the other is
368     *    not, then the conversions from Section 4.1.10 "Implicit
369     *    Conversions" are applied to the non-floating-point-based operand."
370     */
371    if (!apply_implicit_conversion(type_a, value_b, state)
372        && !apply_implicit_conversion(type_b, value_a, state)) {
373       _mesa_glsl_error(loc, state,
374                        "could not implicitly convert operands to "
375                        "arithmetic operator");
376       return glsl_type::error_type;
377    }
378    type_a = value_a->type;
379    type_b = value_b->type;
380 
381    /*    "If the operands are integer types, they must both be signed or
382     *    both be unsigned."
383     *
384     * From this rule and the preceeding conversion it can be inferred that
385     * both types must be GLSL_TYPE_FLOAT, or GLSL_TYPE_UINT, or GLSL_TYPE_INT.
386     * The is_numeric check above already filtered out the case where either
387     * type is not one of these, so now the base types need only be tested for
388     * equality.
389     */
390    if (type_a->base_type != type_b->base_type) {
391       _mesa_glsl_error(loc, state,
392                        "base type mismatch for arithmetic operator");
393       return glsl_type::error_type;
394    }
395 
396    /*    "All arithmetic binary operators result in the same fundamental type
397     *    (signed integer, unsigned integer, or floating-point) as the
398     *    operands they operate on, after operand type conversion. After
399     *    conversion, the following cases are valid
400     *
401     *    * The two operands are scalars. In this case the operation is
402     *      applied, resulting in a scalar."
403     */
404    if (type_a->is_scalar() && type_b->is_scalar())
405       return type_a;
406 
407    /*   "* One operand is a scalar, and the other is a vector or matrix.
408     *      In this case, the scalar operation is applied independently to each
409     *      component of the vector or matrix, resulting in the same size
410     *      vector or matrix."
411     */
412    if (type_a->is_scalar()) {
413       if (!type_b->is_scalar())
414          return type_b;
415    } else if (type_b->is_scalar()) {
416       return type_a;
417    }
418 
419    /* All of the combinations of <scalar, scalar>, <vector, scalar>,
420     * <scalar, vector>, <scalar, matrix>, and <matrix, scalar> have been
421     * handled.
422     */
423    assert(!type_a->is_scalar());
424    assert(!type_b->is_scalar());
425 
426    /*   "* The two operands are vectors of the same size. In this case, the
427     *      operation is done component-wise resulting in the same size
428     *      vector."
429     */
430    if (type_a->is_vector() && type_b->is_vector()) {
431       if (type_a == type_b) {
432          return type_a;
433       } else {
434          _mesa_glsl_error(loc, state,
435                           "vector size mismatch for arithmetic operator");
436          return glsl_type::error_type;
437       }
438    }
439 
440    /* All of the combinations of <scalar, scalar>, <vector, scalar>,
441     * <scalar, vector>, <scalar, matrix>, <matrix, scalar>, and
442     * <vector, vector> have been handled.  At least one of the operands must
443     * be matrix.  Further, since there are no integer matrix types, the base
444     * type of both operands must be float.
445     */
446    assert(type_a->is_matrix() || type_b->is_matrix());
447    assert(type_a->is_float() || type_a->is_double());
448    assert(type_b->is_float() || type_b->is_double());
449 
450    /*   "* The operator is add (+), subtract (-), or divide (/), and the
451     *      operands are matrices with the same number of rows and the same
452     *      number of columns. In this case, the operation is done component-
453     *      wise resulting in the same size matrix."
454     *    * The operator is multiply (*), where both operands are matrices or
455     *      one operand is a vector and the other a matrix. A right vector
456     *      operand is treated as a column vector and a left vector operand as a
457     *      row vector. In all these cases, it is required that the number of
458     *      columns of the left operand is equal to the number of rows of the
459     *      right operand. Then, the multiply (*) operation does a linear
460     *      algebraic multiply, yielding an object that has the same number of
461     *      rows as the left operand and the same number of columns as the right
462     *      operand. Section 5.10 "Vector and Matrix Operations" explains in
463     *      more detail how vectors and matrices are operated on."
464     */
465    if (! multiply) {
466       if (type_a == type_b)
467          return type_a;
468    } else {
469       const glsl_type *type = glsl_type::get_mul_type(type_a, type_b);
470 
471       if (type == glsl_type::error_type) {
472          _mesa_glsl_error(loc, state,
473                           "size mismatch for matrix multiplication");
474       }
475 
476       return type;
477    }
478 
479 
480    /*    "All other cases are illegal."
481     */
482    _mesa_glsl_error(loc, state, "type mismatch");
483    return glsl_type::error_type;
484 }
485 
486 
487 static const struct glsl_type *
unary_arithmetic_result_type(const struct glsl_type * type,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)488 unary_arithmetic_result_type(const struct glsl_type *type,
489                              struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
490 {
491    /* From GLSL 1.50 spec, page 57:
492     *
493     *    "The arithmetic unary operators negate (-), post- and pre-increment
494     *     and decrement (-- and ++) operate on integer or floating-point
495     *     values (including vectors and matrices). All unary operators work
496     *     component-wise on their operands. These result with the same type
497     *     they operated on."
498     */
499    if (!type->is_numeric()) {
500       _mesa_glsl_error(loc, state,
501                        "operands to arithmetic operators must be numeric");
502       return glsl_type::error_type;
503    }
504 
505    return type;
506 }
507 
508 /**
509  * \brief Return the result type of a bit-logic operation.
510  *
511  * If the given types to the bit-logic operator are invalid, return
512  * glsl_type::error_type.
513  *
514  * \param value_a LHS of bit-logic op
515  * \param value_b RHS of bit-logic op
516  */
517 static const struct glsl_type *
bit_logic_result_type(ir_rvalue * & value_a,ir_rvalue * & value_b,ast_operators op,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)518 bit_logic_result_type(ir_rvalue * &value_a, ir_rvalue * &value_b,
519                       ast_operators op,
520                       struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
521 {
522    const glsl_type *type_a = value_a->type;
523    const glsl_type *type_b = value_b->type;
524 
525    if (!state->check_bitwise_operations_allowed(loc)) {
526       return glsl_type::error_type;
527    }
528 
529    /* From page 50 (page 56 of PDF) of GLSL 1.30 spec:
530     *
531     *     "The bitwise operators and (&), exclusive-or (^), and inclusive-or
532     *     (|). The operands must be of type signed or unsigned integers or
533     *     integer vectors."
534     */
535    if (!type_a->is_integer_32_64()) {
536       _mesa_glsl_error(loc, state, "LHS of `%s' must be an integer",
537                         ast_expression::operator_string(op));
538       return glsl_type::error_type;
539    }
540    if (!type_b->is_integer_32_64()) {
541       _mesa_glsl_error(loc, state, "RHS of `%s' must be an integer",
542                        ast_expression::operator_string(op));
543       return glsl_type::error_type;
544    }
545 
546    /* Prior to GLSL 4.0 / GL_ARB_gpu_shader5, implicit conversions didn't
547     * make sense for bitwise operations, as they don't operate on floats.
548     *
549     * GLSL 4.0 added implicit int -> uint conversions, which are relevant
550     * here.  It wasn't clear whether or not we should apply them to bitwise
551     * operations.  However, Khronos has decided that they should in future
552     * language revisions.  Applications also rely on this behavior.  We opt
553     * to apply them in general, but issue a portability warning.
554     *
555     * See https://www.khronos.org/bugzilla/show_bug.cgi?id=1405
556     */
557    if (type_a->base_type != type_b->base_type) {
558       if (!apply_implicit_conversion(type_a, value_b, state)
559           && !apply_implicit_conversion(type_b, value_a, state)) {
560          _mesa_glsl_error(loc, state,
561                           "could not implicitly convert operands to "
562                           "`%s` operator",
563                           ast_expression::operator_string(op));
564          return glsl_type::error_type;
565       } else {
566          _mesa_glsl_warning(loc, state,
567                             "some implementations may not support implicit "
568                             "int -> uint conversions for `%s' operators; "
569                             "consider casting explicitly for portability",
570                             ast_expression::operator_string(op));
571       }
572       type_a = value_a->type;
573       type_b = value_b->type;
574    }
575 
576    /*     "The fundamental types of the operands (signed or unsigned) must
577     *     match,"
578     */
579    if (type_a->base_type != type_b->base_type) {
580       _mesa_glsl_error(loc, state, "operands of `%s' must have the same "
581                        "base type", ast_expression::operator_string(op));
582       return glsl_type::error_type;
583    }
584 
585    /*     "The operands cannot be vectors of differing size." */
586    if (type_a->is_vector() &&
587        type_b->is_vector() &&
588        type_a->vector_elements != type_b->vector_elements) {
589       _mesa_glsl_error(loc, state, "operands of `%s' cannot be vectors of "
590                        "different sizes", ast_expression::operator_string(op));
591       return glsl_type::error_type;
592    }
593 
594    /*     "If one operand is a scalar and the other a vector, the scalar is
595     *     applied component-wise to the vector, resulting in the same type as
596     *     the vector. The fundamental types of the operands [...] will be the
597     *     resulting fundamental type."
598     */
599    if (type_a->is_scalar())
600        return type_b;
601    else
602        return type_a;
603 }
604 
605 static const struct glsl_type *
modulus_result_type(ir_rvalue * & value_a,ir_rvalue * & value_b,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)606 modulus_result_type(ir_rvalue * &value_a, ir_rvalue * &value_b,
607                     struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
608 {
609    const glsl_type *type_a = value_a->type;
610    const glsl_type *type_b = value_b->type;
611 
612    if (!state->check_version(130, 300, loc, "operator '%%' is reserved")) {
613       return glsl_type::error_type;
614    }
615 
616    /* Section 5.9 (Expressions) of the GLSL 4.00 specification says:
617     *
618     *    "The operator modulus (%) operates on signed or unsigned integers or
619     *    integer vectors."
620     */
621    if (!type_a->is_integer_32_64()) {
622       _mesa_glsl_error(loc, state, "LHS of operator %% must be an integer");
623       return glsl_type::error_type;
624    }
625    if (!type_b->is_integer_32_64()) {
626       _mesa_glsl_error(loc, state, "RHS of operator %% must be an integer");
627       return glsl_type::error_type;
628    }
629 
630    /*    "If the fundamental types in the operands do not match, then the
631     *    conversions from section 4.1.10 "Implicit Conversions" are applied
632     *    to create matching types."
633     *
634     * Note that GLSL 4.00 (and GL_ARB_gpu_shader5) introduced implicit
635     * int -> uint conversion rules.  Prior to that, there were no implicit
636     * conversions.  So it's harmless to apply them universally - no implicit
637     * conversions will exist.  If the types don't match, we'll receive false,
638     * and raise an error, satisfying the GLSL 1.50 spec, page 56:
639     *
640     *    "The operand types must both be signed or unsigned."
641     */
642    if (!apply_implicit_conversion(type_a, value_b, state) &&
643        !apply_implicit_conversion(type_b, value_a, state)) {
644       _mesa_glsl_error(loc, state,
645                        "could not implicitly convert operands to "
646                        "modulus (%%) operator");
647       return glsl_type::error_type;
648    }
649    type_a = value_a->type;
650    type_b = value_b->type;
651 
652    /*    "The operands cannot be vectors of differing size. If one operand is
653     *    a scalar and the other vector, then the scalar is applied component-
654     *    wise to the vector, resulting in the same type as the vector. If both
655     *    are vectors of the same size, the result is computed component-wise."
656     */
657    if (type_a->is_vector()) {
658       if (!type_b->is_vector()
659           || (type_a->vector_elements == type_b->vector_elements))
660       return type_a;
661    } else
662       return type_b;
663 
664    /*    "The operator modulus (%) is not defined for any other data types
665     *    (non-integer types)."
666     */
667    _mesa_glsl_error(loc, state, "type mismatch");
668    return glsl_type::error_type;
669 }
670 
671 
672 static const struct glsl_type *
relational_result_type(ir_rvalue * & value_a,ir_rvalue * & value_b,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)673 relational_result_type(ir_rvalue * &value_a, ir_rvalue * &value_b,
674                        struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
675 {
676    const glsl_type *type_a = value_a->type;
677    const glsl_type *type_b = value_b->type;
678 
679    /* From GLSL 1.50 spec, page 56:
680     *    "The relational operators greater than (>), less than (<), greater
681     *    than or equal (>=), and less than or equal (<=) operate only on
682     *    scalar integer and scalar floating-point expressions."
683     */
684    if (!type_a->is_numeric()
685        || !type_b->is_numeric()
686        || !type_a->is_scalar()
687        || !type_b->is_scalar()) {
688       _mesa_glsl_error(loc, state,
689                        "operands to relational operators must be scalar and "
690                        "numeric");
691       return glsl_type::error_type;
692    }
693 
694    /*    "Either the operands' types must match, or the conversions from
695     *    Section 4.1.10 "Implicit Conversions" will be applied to the integer
696     *    operand, after which the types must match."
697     */
698    if (!apply_implicit_conversion(type_a, value_b, state)
699        && !apply_implicit_conversion(type_b, value_a, state)) {
700       _mesa_glsl_error(loc, state,
701                        "could not implicitly convert operands to "
702                        "relational operator");
703       return glsl_type::error_type;
704    }
705    type_a = value_a->type;
706    type_b = value_b->type;
707 
708    if (type_a->base_type != type_b->base_type) {
709       _mesa_glsl_error(loc, state, "base type mismatch");
710       return glsl_type::error_type;
711    }
712 
713    /*    "The result is scalar Boolean."
714     */
715    return glsl_type::bool_type;
716 }
717 
718 /**
719  * \brief Return the result type of a bit-shift operation.
720  *
721  * If the given types to the bit-shift operator are invalid, return
722  * glsl_type::error_type.
723  *
724  * \param type_a Type of LHS of bit-shift op
725  * \param type_b Type of RHS of bit-shift op
726  */
727 static const struct glsl_type *
shift_result_type(const struct glsl_type * type_a,const struct glsl_type * type_b,ast_operators op,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)728 shift_result_type(const struct glsl_type *type_a,
729                   const struct glsl_type *type_b,
730                   ast_operators op,
731                   struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
732 {
733    if (!state->check_bitwise_operations_allowed(loc)) {
734       return glsl_type::error_type;
735    }
736 
737    /* From page 50 (page 56 of the PDF) of the GLSL 1.30 spec:
738     *
739     *     "The shift operators (<<) and (>>). For both operators, the operands
740     *     must be signed or unsigned integers or integer vectors. One operand
741     *     can be signed while the other is unsigned."
742     */
743    if (!type_a->is_integer_32_64()) {
744       _mesa_glsl_error(loc, state, "LHS of operator %s must be an integer or "
745                        "integer vector", ast_expression::operator_string(op));
746      return glsl_type::error_type;
747 
748    }
749    if (!type_b->is_integer()) {
750       _mesa_glsl_error(loc, state, "RHS of operator %s must be an integer or "
751                        "integer vector", ast_expression::operator_string(op));
752      return glsl_type::error_type;
753    }
754 
755    /*     "If the first operand is a scalar, the second operand has to be
756     *     a scalar as well."
757     */
758    if (type_a->is_scalar() && !type_b->is_scalar()) {
759       _mesa_glsl_error(loc, state, "if the first operand of %s is scalar, the "
760                        "second must be scalar as well",
761                        ast_expression::operator_string(op));
762      return glsl_type::error_type;
763    }
764 
765    /* If both operands are vectors, check that they have same number of
766     * elements.
767     */
768    if (type_a->is_vector() &&
769       type_b->is_vector() &&
770       type_a->vector_elements != type_b->vector_elements) {
771       _mesa_glsl_error(loc, state, "vector operands to operator %s must "
772                        "have same number of elements",
773                        ast_expression::operator_string(op));
774      return glsl_type::error_type;
775    }
776 
777    /*     "In all cases, the resulting type will be the same type as the left
778     *     operand."
779     */
780    return type_a;
781 }
782 
783 /**
784  * Returns the innermost array index expression in an rvalue tree.
785  * This is the largest indexing level -- if an array of blocks, then
786  * it is the block index rather than an indexing expression for an
787  * array-typed member of an array of blocks.
788  */
789 static ir_rvalue *
find_innermost_array_index(ir_rvalue * rv)790 find_innermost_array_index(ir_rvalue *rv)
791 {
792    ir_dereference_array *last = NULL;
793    while (rv) {
794       if (rv->as_dereference_array()) {
795          last = rv->as_dereference_array();
796          rv = last->array;
797       } else if (rv->as_dereference_record())
798          rv = rv->as_dereference_record()->record;
799       else if (rv->as_swizzle())
800          rv = rv->as_swizzle()->val;
801       else
802          rv = NULL;
803    }
804 
805    if (last)
806       return last->array_index;
807 
808    return NULL;
809 }
810 
811 /**
812  * Validates that a value can be assigned to a location with a specified type
813  *
814  * Validates that \c rhs can be assigned to some location.  If the types are
815  * not an exact match but an automatic conversion is possible, \c rhs will be
816  * converted.
817  *
818  * \return
819  * \c NULL if \c rhs cannot be assigned to a location with type \c lhs_type.
820  * Otherwise the actual RHS to be assigned will be returned.  This may be
821  * \c rhs, or it may be \c rhs after some type conversion.
822  *
823  * \note
824  * In addition to being used for assignments, this function is used to
825  * type-check return values.
826  */
827 static ir_rvalue *
validate_assignment(struct _mesa_glsl_parse_state * state,YYLTYPE loc,ir_rvalue * lhs,ir_rvalue * rhs,bool is_initializer)828 validate_assignment(struct _mesa_glsl_parse_state *state,
829                     YYLTYPE loc, ir_rvalue *lhs,
830                     ir_rvalue *rhs, bool is_initializer)
831 {
832    /* If there is already some error in the RHS, just return it.  Anything
833     * else will lead to an avalanche of error message back to the user.
834     */
835    if (rhs->type->is_error())
836       return rhs;
837 
838    /* In the Tessellation Control Shader:
839     * If a per-vertex output variable is used as an l-value, it is an error
840     * if the expression indicating the vertex number is not the identifier
841     * `gl_InvocationID`.
842     */
843    if (state->stage == MESA_SHADER_TESS_CTRL && !lhs->type->is_error()) {
844       ir_variable *var = lhs->variable_referenced();
845       if (var && var->data.mode == ir_var_shader_out && !var->data.patch) {
846          ir_rvalue *index = find_innermost_array_index(lhs);
847          ir_variable *index_var = index ? index->variable_referenced() : NULL;
848          if (!index_var || strcmp(index_var->name, "gl_InvocationID") != 0) {
849             _mesa_glsl_error(&loc, state,
850                              "Tessellation control shader outputs can only "
851                              "be indexed by gl_InvocationID");
852             return NULL;
853          }
854       }
855    }
856 
857    /* If the types are identical, the assignment can trivially proceed.
858     */
859    if (rhs->type == lhs->type)
860       return rhs;
861 
862    /* If the array element types are the same and the LHS is unsized,
863     * the assignment is okay for initializers embedded in variable
864     * declarations.
865     *
866     * Note: Whole-array assignments are not permitted in GLSL 1.10, but this
867     * is handled by ir_dereference::is_lvalue.
868     */
869    const glsl_type *lhs_t = lhs->type;
870    const glsl_type *rhs_t = rhs->type;
871    bool unsized_array = false;
872    while(lhs_t->is_array()) {
873       if (rhs_t == lhs_t)
874          break; /* the rest of the inner arrays match so break out early */
875       if (!rhs_t->is_array()) {
876          unsized_array = false;
877          break; /* number of dimensions mismatch */
878       }
879       if (lhs_t->length == rhs_t->length) {
880          lhs_t = lhs_t->fields.array;
881          rhs_t = rhs_t->fields.array;
882          continue;
883       } else if (lhs_t->is_unsized_array()) {
884          unsized_array = true;
885       } else {
886          unsized_array = false;
887          break; /* sized array mismatch */
888       }
889       lhs_t = lhs_t->fields.array;
890       rhs_t = rhs_t->fields.array;
891    }
892    if (unsized_array) {
893       if (is_initializer) {
894          return rhs;
895       } else {
896          _mesa_glsl_error(&loc, state,
897                           "implicitly sized arrays cannot be assigned");
898          return NULL;
899       }
900    }
901 
902    /* Check for implicit conversion in GLSL 1.20 */
903    if (apply_implicit_conversion(lhs->type, rhs, state)) {
904       if (rhs->type == lhs->type)
905          return rhs;
906    }
907 
908    _mesa_glsl_error(&loc, state,
909                     "%s of type %s cannot be assigned to "
910                     "variable of type %s",
911                     is_initializer ? "initializer" : "value",
912                     rhs->type->name, lhs->type->name);
913 
914    return NULL;
915 }
916 
917 static void
mark_whole_array_access(ir_rvalue * access)918 mark_whole_array_access(ir_rvalue *access)
919 {
920    ir_dereference_variable *deref = access->as_dereference_variable();
921 
922    if (deref && deref->var) {
923       deref->var->data.max_array_access = deref->type->length - 1;
924    }
925 }
926 
927 static bool
do_assignment(exec_list * instructions,struct _mesa_glsl_parse_state * state,const char * non_lvalue_description,ir_rvalue * lhs,ir_rvalue * rhs,ir_rvalue ** out_rvalue,bool needs_rvalue,bool is_initializer,YYLTYPE lhs_loc)928 do_assignment(exec_list *instructions, struct _mesa_glsl_parse_state *state,
929               const char *non_lvalue_description,
930               ir_rvalue *lhs, ir_rvalue *rhs,
931               ir_rvalue **out_rvalue, bool needs_rvalue,
932               bool is_initializer,
933               YYLTYPE lhs_loc)
934 {
935    void *ctx = state;
936    bool error_emitted = (lhs->type->is_error() || rhs->type->is_error());
937 
938    ir_variable *lhs_var = lhs->variable_referenced();
939    if (lhs_var)
940       lhs_var->data.assigned = true;
941 
942    if (!error_emitted) {
943       if (non_lvalue_description != NULL) {
944          _mesa_glsl_error(&lhs_loc, state,
945                           "assignment to %s",
946                           non_lvalue_description);
947          error_emitted = true;
948       } else if (lhs_var != NULL && (lhs_var->data.read_only ||
949                  (lhs_var->data.mode == ir_var_shader_storage &&
950                   lhs_var->data.memory_read_only))) {
951          /* We can have memory_read_only set on both images and buffer variables,
952           * but in the former there is a distinction between assignments to
953           * the variable itself (read_only) and to the memory they point to
954           * (memory_read_only), while in the case of buffer variables there is
955           * no such distinction, that is why this check here is limited to
956           * buffer variables alone.
957           */
958          _mesa_glsl_error(&lhs_loc, state,
959                           "assignment to read-only variable '%s'",
960                           lhs_var->name);
961          error_emitted = true;
962       } else if (lhs->type->is_array() &&
963                  !state->check_version(120, 300, &lhs_loc,
964                                        "whole array assignment forbidden")) {
965          /* From page 32 (page 38 of the PDF) of the GLSL 1.10 spec:
966           *
967           *    "Other binary or unary expressions, non-dereferenced
968           *     arrays, function names, swizzles with repeated fields,
969           *     and constants cannot be l-values."
970           *
971           * The restriction on arrays is lifted in GLSL 1.20 and GLSL ES 3.00.
972           */
973          error_emitted = true;
974       } else if (!lhs->is_lvalue(state)) {
975          _mesa_glsl_error(& lhs_loc, state, "non-lvalue in assignment");
976          error_emitted = true;
977       }
978    }
979 
980    ir_rvalue *new_rhs =
981       validate_assignment(state, lhs_loc, lhs, rhs, is_initializer);
982    if (new_rhs != NULL) {
983       rhs = new_rhs;
984 
985       /* If the LHS array was not declared with a size, it takes it size from
986        * the RHS.  If the LHS is an l-value and a whole array, it must be a
987        * dereference of a variable.  Any other case would require that the LHS
988        * is either not an l-value or not a whole array.
989        */
990       if (lhs->type->is_unsized_array()) {
991          ir_dereference *const d = lhs->as_dereference();
992 
993          assert(d != NULL);
994 
995          ir_variable *const var = d->variable_referenced();
996 
997          assert(var != NULL);
998 
999          if (var->data.max_array_access >= rhs->type->array_size()) {
1000             /* FINISHME: This should actually log the location of the RHS. */
1001             _mesa_glsl_error(& lhs_loc, state, "array size must be > %u due to "
1002                              "previous access",
1003                              var->data.max_array_access);
1004          }
1005 
1006          var->type = glsl_type::get_array_instance(lhs->type->fields.array,
1007                                                    rhs->type->array_size());
1008          d->type = var->type;
1009       }
1010       if (lhs->type->is_array()) {
1011          mark_whole_array_access(rhs);
1012          mark_whole_array_access(lhs);
1013       }
1014    }
1015 
1016    /* Most callers of do_assignment (assign, add_assign, pre_inc/dec,
1017     * but not post_inc) need the converted assigned value as an rvalue
1018     * to handle things like:
1019     *
1020     * i = j += 1;
1021     */
1022    if (needs_rvalue) {
1023       ir_rvalue *rvalue;
1024       if (!error_emitted) {
1025          ir_variable *var = new(ctx) ir_variable(rhs->type, "assignment_tmp",
1026                                                  ir_var_temporary);
1027          instructions->push_tail(var);
1028          instructions->push_tail(assign(var, rhs));
1029 
1030          ir_dereference_variable *deref_var =
1031             new(ctx) ir_dereference_variable(var);
1032          instructions->push_tail(new(ctx) ir_assignment(lhs, deref_var));
1033          rvalue = new(ctx) ir_dereference_variable(var);
1034       } else {
1035          rvalue = ir_rvalue::error_value(ctx);
1036       }
1037       *out_rvalue = rvalue;
1038    } else {
1039       if (!error_emitted)
1040          instructions->push_tail(new(ctx) ir_assignment(lhs, rhs));
1041       *out_rvalue = NULL;
1042    }
1043 
1044    return error_emitted;
1045 }
1046 
1047 static ir_rvalue *
get_lvalue_copy(exec_list * instructions,ir_rvalue * lvalue)1048 get_lvalue_copy(exec_list *instructions, ir_rvalue *lvalue)
1049 {
1050    void *ctx = ralloc_parent(lvalue);
1051    ir_variable *var;
1052 
1053    var = new(ctx) ir_variable(lvalue->type, "_post_incdec_tmp",
1054                               ir_var_temporary);
1055    instructions->push_tail(var);
1056 
1057    instructions->push_tail(new(ctx) ir_assignment(new(ctx) ir_dereference_variable(var),
1058                                                   lvalue));
1059 
1060    return new(ctx) ir_dereference_variable(var);
1061 }
1062 
1063 
1064 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)1065 ast_node::hir(exec_list *instructions, struct _mesa_glsl_parse_state *state)
1066 {
1067    (void) instructions;
1068    (void) state;
1069 
1070    return NULL;
1071 }
1072 
1073 bool
has_sequence_subexpression() const1074 ast_node::has_sequence_subexpression() const
1075 {
1076    return false;
1077 }
1078 
1079 void
set_is_lhs(bool)1080 ast_node::set_is_lhs(bool /* new_value */)
1081 {
1082 }
1083 
1084 void
hir_no_rvalue(exec_list * instructions,struct _mesa_glsl_parse_state * state)1085 ast_function_expression::hir_no_rvalue(exec_list *instructions,
1086                                        struct _mesa_glsl_parse_state *state)
1087 {
1088    (void)hir(instructions, state);
1089 }
1090 
1091 void
hir_no_rvalue(exec_list * instructions,struct _mesa_glsl_parse_state * state)1092 ast_aggregate_initializer::hir_no_rvalue(exec_list *instructions,
1093                                          struct _mesa_glsl_parse_state *state)
1094 {
1095    (void)hir(instructions, state);
1096 }
1097 
1098 static ir_rvalue *
do_comparison(void * mem_ctx,int operation,ir_rvalue * op0,ir_rvalue * op1)1099 do_comparison(void *mem_ctx, int operation, ir_rvalue *op0, ir_rvalue *op1)
1100 {
1101    int join_op;
1102    ir_rvalue *cmp = NULL;
1103 
1104    if (operation == ir_binop_all_equal)
1105       join_op = ir_binop_logic_and;
1106    else
1107       join_op = ir_binop_logic_or;
1108 
1109    switch (op0->type->base_type) {
1110    case GLSL_TYPE_FLOAT:
1111    case GLSL_TYPE_FLOAT16:
1112    case GLSL_TYPE_UINT:
1113    case GLSL_TYPE_INT:
1114    case GLSL_TYPE_BOOL:
1115    case GLSL_TYPE_DOUBLE:
1116    case GLSL_TYPE_UINT64:
1117    case GLSL_TYPE_INT64:
1118    case GLSL_TYPE_UINT16:
1119    case GLSL_TYPE_INT16:
1120       return new(mem_ctx) ir_expression(operation, op0, op1);
1121 
1122    case GLSL_TYPE_ARRAY: {
1123       for (unsigned int i = 0; i < op0->type->length; i++) {
1124          ir_rvalue *e0, *e1, *result;
1125 
1126          e0 = new(mem_ctx) ir_dereference_array(op0->clone(mem_ctx, NULL),
1127                                                 new(mem_ctx) ir_constant(i));
1128          e1 = new(mem_ctx) ir_dereference_array(op1->clone(mem_ctx, NULL),
1129                                                 new(mem_ctx) ir_constant(i));
1130          result = do_comparison(mem_ctx, operation, e0, e1);
1131 
1132          if (cmp) {
1133             cmp = new(mem_ctx) ir_expression(join_op, cmp, result);
1134          } else {
1135             cmp = result;
1136          }
1137       }
1138 
1139       mark_whole_array_access(op0);
1140       mark_whole_array_access(op1);
1141       break;
1142    }
1143 
1144    case GLSL_TYPE_STRUCT: {
1145       for (unsigned int i = 0; i < op0->type->length; i++) {
1146          ir_rvalue *e0, *e1, *result;
1147          const char *field_name = op0->type->fields.structure[i].name;
1148 
1149          e0 = new(mem_ctx) ir_dereference_record(op0->clone(mem_ctx, NULL),
1150                                                  field_name);
1151          e1 = new(mem_ctx) ir_dereference_record(op1->clone(mem_ctx, NULL),
1152                                                  field_name);
1153          result = do_comparison(mem_ctx, operation, e0, e1);
1154 
1155          if (cmp) {
1156             cmp = new(mem_ctx) ir_expression(join_op, cmp, result);
1157          } else {
1158             cmp = result;
1159          }
1160       }
1161       break;
1162    }
1163 
1164    case GLSL_TYPE_ERROR:
1165    case GLSL_TYPE_VOID:
1166    case GLSL_TYPE_SAMPLER:
1167    case GLSL_TYPE_IMAGE:
1168    case GLSL_TYPE_INTERFACE:
1169    case GLSL_TYPE_ATOMIC_UINT:
1170    case GLSL_TYPE_SUBROUTINE:
1171    case GLSL_TYPE_FUNCTION:
1172       /* I assume a comparison of a struct containing a sampler just
1173        * ignores the sampler present in the type.
1174        */
1175       break;
1176    }
1177 
1178    if (cmp == NULL)
1179       cmp = new(mem_ctx) ir_constant(true);
1180 
1181    return cmp;
1182 }
1183 
1184 /* For logical operations, we want to ensure that the operands are
1185  * scalar booleans.  If it isn't, emit an error and return a constant
1186  * boolean to avoid triggering cascading error messages.
1187  */
1188 static ir_rvalue *
get_scalar_boolean_operand(exec_list * instructions,struct _mesa_glsl_parse_state * state,ast_expression * parent_expr,int operand,const char * operand_name,bool * error_emitted)1189 get_scalar_boolean_operand(exec_list *instructions,
1190                            struct _mesa_glsl_parse_state *state,
1191                            ast_expression *parent_expr,
1192                            int operand,
1193                            const char *operand_name,
1194                            bool *error_emitted)
1195 {
1196    ast_expression *expr = parent_expr->subexpressions[operand];
1197    void *ctx = state;
1198    ir_rvalue *val = expr->hir(instructions, state);
1199 
1200    if (val->type->is_boolean() && val->type->is_scalar())
1201       return val;
1202 
1203    if (!*error_emitted) {
1204       YYLTYPE loc = expr->get_location();
1205       _mesa_glsl_error(&loc, state, "%s of `%s' must be scalar boolean",
1206                        operand_name,
1207                        parent_expr->operator_string(parent_expr->oper));
1208       *error_emitted = true;
1209    }
1210 
1211    return new(ctx) ir_constant(true);
1212 }
1213 
1214 /**
1215  * If name refers to a builtin array whose maximum allowed size is less than
1216  * size, report an error and return true.  Otherwise return false.
1217  */
1218 void
check_builtin_array_max_size(const char * name,unsigned size,YYLTYPE loc,struct _mesa_glsl_parse_state * state)1219 check_builtin_array_max_size(const char *name, unsigned size,
1220                              YYLTYPE loc, struct _mesa_glsl_parse_state *state)
1221 {
1222    if ((strcmp("gl_TexCoord", name) == 0)
1223        && (size > state->Const.MaxTextureCoords)) {
1224       /* From page 54 (page 60 of the PDF) of the GLSL 1.20 spec:
1225        *
1226        *     "The size [of gl_TexCoord] can be at most
1227        *     gl_MaxTextureCoords."
1228        */
1229       _mesa_glsl_error(&loc, state, "`gl_TexCoord' array size cannot "
1230                        "be larger than gl_MaxTextureCoords (%u)",
1231                        state->Const.MaxTextureCoords);
1232    } else if (strcmp("gl_ClipDistance", name) == 0) {
1233       state->clip_dist_size = size;
1234       if (size + state->cull_dist_size > state->Const.MaxClipPlanes) {
1235          /* From section 7.1 (Vertex Shader Special Variables) of the
1236           * GLSL 1.30 spec:
1237           *
1238           *   "The gl_ClipDistance array is predeclared as unsized and
1239           *   must be sized by the shader either redeclaring it with a
1240           *   size or indexing it only with integral constant
1241           *   expressions. ... The size can be at most
1242           *   gl_MaxClipDistances."
1243           */
1244          _mesa_glsl_error(&loc, state, "`gl_ClipDistance' array size cannot "
1245                           "be larger than gl_MaxClipDistances (%u)",
1246                           state->Const.MaxClipPlanes);
1247       }
1248    } else if (strcmp("gl_CullDistance", name) == 0) {
1249       state->cull_dist_size = size;
1250       if (size + state->clip_dist_size > state->Const.MaxClipPlanes) {
1251          /* From the ARB_cull_distance spec:
1252           *
1253           *   "The gl_CullDistance array is predeclared as unsized and
1254           *    must be sized by the shader either redeclaring it with
1255           *    a size or indexing it only with integral constant
1256           *    expressions. The size determines the number and set of
1257           *    enabled cull distances and can be at most
1258           *    gl_MaxCullDistances."
1259           */
1260          _mesa_glsl_error(&loc, state, "`gl_CullDistance' array size cannot "
1261                           "be larger than gl_MaxCullDistances (%u)",
1262                           state->Const.MaxClipPlanes);
1263       }
1264    }
1265 }
1266 
1267 /**
1268  * Create the constant 1, of a which is appropriate for incrementing and
1269  * decrementing values of the given GLSL type.  For example, if type is vec4,
1270  * this creates a constant value of 1.0 having type float.
1271  *
1272  * If the given type is invalid for increment and decrement operators, return
1273  * a floating point 1--the error will be detected later.
1274  */
1275 static ir_rvalue *
constant_one_for_inc_dec(void * ctx,const glsl_type * type)1276 constant_one_for_inc_dec(void *ctx, const glsl_type *type)
1277 {
1278    switch (type->base_type) {
1279    case GLSL_TYPE_UINT:
1280       return new(ctx) ir_constant((unsigned) 1);
1281    case GLSL_TYPE_INT:
1282       return new(ctx) ir_constant(1);
1283    case GLSL_TYPE_UINT64:
1284       return new(ctx) ir_constant((uint64_t) 1);
1285    case GLSL_TYPE_INT64:
1286       return new(ctx) ir_constant((int64_t) 1);
1287    default:
1288    case GLSL_TYPE_FLOAT:
1289       return new(ctx) ir_constant(1.0f);
1290    }
1291 }
1292 
1293 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)1294 ast_expression::hir(exec_list *instructions,
1295                     struct _mesa_glsl_parse_state *state)
1296 {
1297    return do_hir(instructions, state, true);
1298 }
1299 
1300 void
hir_no_rvalue(exec_list * instructions,struct _mesa_glsl_parse_state * state)1301 ast_expression::hir_no_rvalue(exec_list *instructions,
1302                               struct _mesa_glsl_parse_state *state)
1303 {
1304    do_hir(instructions, state, false);
1305 }
1306 
1307 void
set_is_lhs(bool new_value)1308 ast_expression::set_is_lhs(bool new_value)
1309 {
1310    /* is_lhs is tracked only to print "variable used uninitialized" warnings,
1311     * if we lack an identifier we can just skip it.
1312     */
1313    if (this->primary_expression.identifier == NULL)
1314       return;
1315 
1316    this->is_lhs = new_value;
1317 
1318    /* We need to go through the subexpressions tree to cover cases like
1319     * ast_field_selection
1320     */
1321    if (this->subexpressions[0] != NULL)
1322       this->subexpressions[0]->set_is_lhs(new_value);
1323 }
1324 
1325 ir_rvalue *
do_hir(exec_list * instructions,struct _mesa_glsl_parse_state * state,bool needs_rvalue)1326 ast_expression::do_hir(exec_list *instructions,
1327                        struct _mesa_glsl_parse_state *state,
1328                        bool needs_rvalue)
1329 {
1330    void *ctx = state;
1331    static const int operations[AST_NUM_OPERATORS] = {
1332       -1,               /* ast_assign doesn't convert to ir_expression. */
1333       -1,               /* ast_plus doesn't convert to ir_expression. */
1334       ir_unop_neg,
1335       ir_binop_add,
1336       ir_binop_sub,
1337       ir_binop_mul,
1338       ir_binop_div,
1339       ir_binop_mod,
1340       ir_binop_lshift,
1341       ir_binop_rshift,
1342       ir_binop_less,
1343       ir_binop_less,    /* This is correct.  See the ast_greater case below. */
1344       ir_binop_gequal,  /* This is correct.  See the ast_lequal case below. */
1345       ir_binop_gequal,
1346       ir_binop_all_equal,
1347       ir_binop_any_nequal,
1348       ir_binop_bit_and,
1349       ir_binop_bit_xor,
1350       ir_binop_bit_or,
1351       ir_unop_bit_not,
1352       ir_binop_logic_and,
1353       ir_binop_logic_xor,
1354       ir_binop_logic_or,
1355       ir_unop_logic_not,
1356 
1357       /* Note: The following block of expression types actually convert
1358        * to multiple IR instructions.
1359        */
1360       ir_binop_mul,     /* ast_mul_assign */
1361       ir_binop_div,     /* ast_div_assign */
1362       ir_binop_mod,     /* ast_mod_assign */
1363       ir_binop_add,     /* ast_add_assign */
1364       ir_binop_sub,     /* ast_sub_assign */
1365       ir_binop_lshift,  /* ast_ls_assign */
1366       ir_binop_rshift,  /* ast_rs_assign */
1367       ir_binop_bit_and, /* ast_and_assign */
1368       ir_binop_bit_xor, /* ast_xor_assign */
1369       ir_binop_bit_or,  /* ast_or_assign */
1370 
1371       -1,               /* ast_conditional doesn't convert to ir_expression. */
1372       ir_binop_add,     /* ast_pre_inc. */
1373       ir_binop_sub,     /* ast_pre_dec. */
1374       ir_binop_add,     /* ast_post_inc. */
1375       ir_binop_sub,     /* ast_post_dec. */
1376       -1,               /* ast_field_selection doesn't conv to ir_expression. */
1377       -1,               /* ast_array_index doesn't convert to ir_expression. */
1378       -1,               /* ast_function_call doesn't conv to ir_expression. */
1379       -1,               /* ast_identifier doesn't convert to ir_expression. */
1380       -1,               /* ast_int_constant doesn't convert to ir_expression. */
1381       -1,               /* ast_uint_constant doesn't conv to ir_expression. */
1382       -1,               /* ast_float_constant doesn't conv to ir_expression. */
1383       -1,               /* ast_bool_constant doesn't conv to ir_expression. */
1384       -1,               /* ast_sequence doesn't convert to ir_expression. */
1385       -1,               /* ast_aggregate shouldn't ever even get here. */
1386    };
1387    ir_rvalue *result = NULL;
1388    ir_rvalue *op[3];
1389    const struct glsl_type *type, *orig_type;
1390    bool error_emitted = false;
1391    YYLTYPE loc;
1392 
1393    loc = this->get_location();
1394 
1395    switch (this->oper) {
1396    case ast_aggregate:
1397       assert(!"ast_aggregate: Should never get here.");
1398       break;
1399 
1400    case ast_assign: {
1401       this->subexpressions[0]->set_is_lhs(true);
1402       op[0] = this->subexpressions[0]->hir(instructions, state);
1403       op[1] = this->subexpressions[1]->hir(instructions, state);
1404 
1405       error_emitted =
1406          do_assignment(instructions, state,
1407                        this->subexpressions[0]->non_lvalue_description,
1408                        op[0], op[1], &result, needs_rvalue, false,
1409                        this->subexpressions[0]->get_location());
1410       break;
1411    }
1412 
1413    case ast_plus:
1414       op[0] = this->subexpressions[0]->hir(instructions, state);
1415 
1416       type = unary_arithmetic_result_type(op[0]->type, state, & loc);
1417 
1418       error_emitted = type->is_error();
1419 
1420       result = op[0];
1421       break;
1422 
1423    case ast_neg:
1424       op[0] = this->subexpressions[0]->hir(instructions, state);
1425 
1426       type = unary_arithmetic_result_type(op[0]->type, state, & loc);
1427 
1428       error_emitted = type->is_error();
1429 
1430       result = new(ctx) ir_expression(operations[this->oper], type,
1431                                       op[0], NULL);
1432       break;
1433 
1434    case ast_add:
1435    case ast_sub:
1436    case ast_mul:
1437    case ast_div:
1438       op[0] = this->subexpressions[0]->hir(instructions, state);
1439       op[1] = this->subexpressions[1]->hir(instructions, state);
1440 
1441       type = arithmetic_result_type(op[0], op[1],
1442                                     (this->oper == ast_mul),
1443                                     state, & loc);
1444       error_emitted = type->is_error();
1445 
1446       result = new(ctx) ir_expression(operations[this->oper], type,
1447                                       op[0], op[1]);
1448       break;
1449 
1450    case ast_mod:
1451       op[0] = this->subexpressions[0]->hir(instructions, state);
1452       op[1] = this->subexpressions[1]->hir(instructions, state);
1453 
1454       type = modulus_result_type(op[0], op[1], state, &loc);
1455 
1456       assert(operations[this->oper] == ir_binop_mod);
1457 
1458       result = new(ctx) ir_expression(operations[this->oper], type,
1459                                       op[0], op[1]);
1460       error_emitted = type->is_error();
1461       break;
1462 
1463    case ast_lshift:
1464    case ast_rshift:
1465        if (!state->check_bitwise_operations_allowed(&loc)) {
1466           error_emitted = true;
1467        }
1468 
1469        op[0] = this->subexpressions[0]->hir(instructions, state);
1470        op[1] = this->subexpressions[1]->hir(instructions, state);
1471        type = shift_result_type(op[0]->type, op[1]->type, this->oper, state,
1472                                 &loc);
1473        result = new(ctx) ir_expression(operations[this->oper], type,
1474                                        op[0], op[1]);
1475        error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1476        break;
1477 
1478    case ast_less:
1479    case ast_greater:
1480    case ast_lequal:
1481    case ast_gequal:
1482       op[0] = this->subexpressions[0]->hir(instructions, state);
1483       op[1] = this->subexpressions[1]->hir(instructions, state);
1484 
1485       type = relational_result_type(op[0], op[1], state, & loc);
1486 
1487       /* The relational operators must either generate an error or result
1488        * in a scalar boolean.  See page 57 of the GLSL 1.50 spec.
1489        */
1490       assert(type->is_error()
1491              || (type->is_boolean() && type->is_scalar()));
1492 
1493       /* Like NIR, GLSL IR does not have opcodes for > or <=.  Instead, swap
1494        * the arguments and use < or >=.
1495        */
1496       if (this->oper == ast_greater || this->oper == ast_lequal) {
1497          ir_rvalue *const tmp = op[0];
1498          op[0] = op[1];
1499          op[1] = tmp;
1500       }
1501 
1502       result = new(ctx) ir_expression(operations[this->oper], type,
1503                                       op[0], op[1]);
1504       error_emitted = type->is_error();
1505       break;
1506 
1507    case ast_nequal:
1508    case ast_equal:
1509       op[0] = this->subexpressions[0]->hir(instructions, state);
1510       op[1] = this->subexpressions[1]->hir(instructions, state);
1511 
1512       /* From page 58 (page 64 of the PDF) of the GLSL 1.50 spec:
1513        *
1514        *    "The equality operators equal (==), and not equal (!=)
1515        *    operate on all types. They result in a scalar Boolean. If
1516        *    the operand types do not match, then there must be a
1517        *    conversion from Section 4.1.10 "Implicit Conversions"
1518        *    applied to one operand that can make them match, in which
1519        *    case this conversion is done."
1520        */
1521 
1522       if (op[0]->type == glsl_type::void_type || op[1]->type == glsl_type::void_type) {
1523          _mesa_glsl_error(& loc, state, "`%s':  wrong operand types: "
1524                          "no operation `%1$s' exists that takes a left-hand "
1525                          "operand of type 'void' or a right operand of type "
1526                          "'void'", (this->oper == ast_equal) ? "==" : "!=");
1527          error_emitted = true;
1528       } else if ((!apply_implicit_conversion(op[0]->type, op[1], state)
1529            && !apply_implicit_conversion(op[1]->type, op[0], state))
1530           || (op[0]->type != op[1]->type)) {
1531          _mesa_glsl_error(& loc, state, "operands of `%s' must have the same "
1532                           "type", (this->oper == ast_equal) ? "==" : "!=");
1533          error_emitted = true;
1534       } else if ((op[0]->type->is_array() || op[1]->type->is_array()) &&
1535                  !state->check_version(120, 300, &loc,
1536                                        "array comparisons forbidden")) {
1537          error_emitted = true;
1538       } else if ((op[0]->type->contains_subroutine() ||
1539                   op[1]->type->contains_subroutine())) {
1540          _mesa_glsl_error(&loc, state, "subroutine comparisons forbidden");
1541          error_emitted = true;
1542       } else if ((op[0]->type->contains_opaque() ||
1543                   op[1]->type->contains_opaque())) {
1544          _mesa_glsl_error(&loc, state, "opaque type comparisons forbidden");
1545          error_emitted = true;
1546       }
1547 
1548       if (error_emitted) {
1549          result = new(ctx) ir_constant(false);
1550       } else {
1551          result = do_comparison(ctx, operations[this->oper], op[0], op[1]);
1552          assert(result->type == glsl_type::bool_type);
1553       }
1554       break;
1555 
1556    case ast_bit_and:
1557    case ast_bit_xor:
1558    case ast_bit_or:
1559       op[0] = this->subexpressions[0]->hir(instructions, state);
1560       op[1] = this->subexpressions[1]->hir(instructions, state);
1561       type = bit_logic_result_type(op[0], op[1], this->oper, state, &loc);
1562       result = new(ctx) ir_expression(operations[this->oper], type,
1563                                       op[0], op[1]);
1564       error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1565       break;
1566 
1567    case ast_bit_not:
1568       op[0] = this->subexpressions[0]->hir(instructions, state);
1569 
1570       if (!state->check_bitwise_operations_allowed(&loc)) {
1571          error_emitted = true;
1572       }
1573 
1574       if (!op[0]->type->is_integer_32_64()) {
1575          _mesa_glsl_error(&loc, state, "operand of `~' must be an integer");
1576          error_emitted = true;
1577       }
1578 
1579       type = error_emitted ? glsl_type::error_type : op[0]->type;
1580       result = new(ctx) ir_expression(ir_unop_bit_not, type, op[0], NULL);
1581       break;
1582 
1583    case ast_logic_and: {
1584       exec_list rhs_instructions;
1585       op[0] = get_scalar_boolean_operand(instructions, state, this, 0,
1586                                          "LHS", &error_emitted);
1587       op[1] = get_scalar_boolean_operand(&rhs_instructions, state, this, 1,
1588                                          "RHS", &error_emitted);
1589 
1590       if (rhs_instructions.is_empty()) {
1591          result = new(ctx) ir_expression(ir_binop_logic_and, op[0], op[1]);
1592       } else {
1593          ir_variable *const tmp = new(ctx) ir_variable(glsl_type::bool_type,
1594                                                        "and_tmp",
1595                                                        ir_var_temporary);
1596          instructions->push_tail(tmp);
1597 
1598          ir_if *const stmt = new(ctx) ir_if(op[0]);
1599          instructions->push_tail(stmt);
1600 
1601          stmt->then_instructions.append_list(&rhs_instructions);
1602          ir_dereference *const then_deref = new(ctx) ir_dereference_variable(tmp);
1603          ir_assignment *const then_assign =
1604             new(ctx) ir_assignment(then_deref, op[1]);
1605          stmt->then_instructions.push_tail(then_assign);
1606 
1607          ir_dereference *const else_deref = new(ctx) ir_dereference_variable(tmp);
1608          ir_assignment *const else_assign =
1609             new(ctx) ir_assignment(else_deref, new(ctx) ir_constant(false));
1610          stmt->else_instructions.push_tail(else_assign);
1611 
1612          result = new(ctx) ir_dereference_variable(tmp);
1613       }
1614       break;
1615    }
1616 
1617    case ast_logic_or: {
1618       exec_list rhs_instructions;
1619       op[0] = get_scalar_boolean_operand(instructions, state, this, 0,
1620                                          "LHS", &error_emitted);
1621       op[1] = get_scalar_boolean_operand(&rhs_instructions, state, this, 1,
1622                                          "RHS", &error_emitted);
1623 
1624       if (rhs_instructions.is_empty()) {
1625          result = new(ctx) ir_expression(ir_binop_logic_or, op[0], op[1]);
1626       } else {
1627          ir_variable *const tmp = new(ctx) ir_variable(glsl_type::bool_type,
1628                                                        "or_tmp",
1629                                                        ir_var_temporary);
1630          instructions->push_tail(tmp);
1631 
1632          ir_if *const stmt = new(ctx) ir_if(op[0]);
1633          instructions->push_tail(stmt);
1634 
1635          ir_dereference *const then_deref = new(ctx) ir_dereference_variable(tmp);
1636          ir_assignment *const then_assign =
1637             new(ctx) ir_assignment(then_deref, new(ctx) ir_constant(true));
1638          stmt->then_instructions.push_tail(then_assign);
1639 
1640          stmt->else_instructions.append_list(&rhs_instructions);
1641          ir_dereference *const else_deref = new(ctx) ir_dereference_variable(tmp);
1642          ir_assignment *const else_assign =
1643             new(ctx) ir_assignment(else_deref, op[1]);
1644          stmt->else_instructions.push_tail(else_assign);
1645 
1646          result = new(ctx) ir_dereference_variable(tmp);
1647       }
1648       break;
1649    }
1650 
1651    case ast_logic_xor:
1652       /* From page 33 (page 39 of the PDF) of the GLSL 1.10 spec:
1653        *
1654        *    "The logical binary operators and (&&), or ( | | ), and
1655        *     exclusive or (^^). They operate only on two Boolean
1656        *     expressions and result in a Boolean expression."
1657        */
1658       op[0] = get_scalar_boolean_operand(instructions, state, this, 0, "LHS",
1659                                          &error_emitted);
1660       op[1] = get_scalar_boolean_operand(instructions, state, this, 1, "RHS",
1661                                          &error_emitted);
1662 
1663       result = new(ctx) ir_expression(operations[this->oper], glsl_type::bool_type,
1664                                       op[0], op[1]);
1665       break;
1666 
1667    case ast_logic_not:
1668       op[0] = get_scalar_boolean_operand(instructions, state, this, 0,
1669                                          "operand", &error_emitted);
1670 
1671       result = new(ctx) ir_expression(operations[this->oper], glsl_type::bool_type,
1672                                       op[0], NULL);
1673       break;
1674 
1675    case ast_mul_assign:
1676    case ast_div_assign:
1677    case ast_add_assign:
1678    case ast_sub_assign: {
1679       this->subexpressions[0]->set_is_lhs(true);
1680       op[0] = this->subexpressions[0]->hir(instructions, state);
1681       op[1] = this->subexpressions[1]->hir(instructions, state);
1682 
1683       orig_type = op[0]->type;
1684       type = arithmetic_result_type(op[0], op[1],
1685                                     (this->oper == ast_mul_assign),
1686                                     state, & loc);
1687 
1688       if (type != orig_type) {
1689          _mesa_glsl_error(& loc, state,
1690                           "could not implicitly convert "
1691                           "%s to %s", type->name, orig_type->name);
1692          type = glsl_type::error_type;
1693       }
1694 
1695       ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper], type,
1696                                                    op[0], op[1]);
1697 
1698       error_emitted =
1699          do_assignment(instructions, state,
1700                        this->subexpressions[0]->non_lvalue_description,
1701                        op[0]->clone(ctx, NULL), temp_rhs,
1702                        &result, needs_rvalue, false,
1703                        this->subexpressions[0]->get_location());
1704 
1705       /* GLSL 1.10 does not allow array assignment.  However, we don't have to
1706        * explicitly test for this because none of the binary expression
1707        * operators allow array operands either.
1708        */
1709 
1710       break;
1711    }
1712 
1713    case ast_mod_assign: {
1714       this->subexpressions[0]->set_is_lhs(true);
1715       op[0] = this->subexpressions[0]->hir(instructions, state);
1716       op[1] = this->subexpressions[1]->hir(instructions, state);
1717 
1718       orig_type = op[0]->type;
1719       type = modulus_result_type(op[0], op[1], state, &loc);
1720 
1721       if (type != orig_type) {
1722          _mesa_glsl_error(& loc, state,
1723                           "could not implicitly convert "
1724                           "%s to %s", type->name, orig_type->name);
1725          type = glsl_type::error_type;
1726       }
1727 
1728       assert(operations[this->oper] == ir_binop_mod);
1729 
1730       ir_rvalue *temp_rhs;
1731       temp_rhs = new(ctx) ir_expression(operations[this->oper], type,
1732                                         op[0], op[1]);
1733 
1734       error_emitted =
1735          do_assignment(instructions, state,
1736                        this->subexpressions[0]->non_lvalue_description,
1737                        op[0]->clone(ctx, NULL), temp_rhs,
1738                        &result, needs_rvalue, false,
1739                        this->subexpressions[0]->get_location());
1740       break;
1741    }
1742 
1743    case ast_ls_assign:
1744    case ast_rs_assign: {
1745       this->subexpressions[0]->set_is_lhs(true);
1746       op[0] = this->subexpressions[0]->hir(instructions, state);
1747       op[1] = this->subexpressions[1]->hir(instructions, state);
1748       type = shift_result_type(op[0]->type, op[1]->type, this->oper, state,
1749                                &loc);
1750       ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper],
1751                                                    type, op[0], op[1]);
1752       error_emitted =
1753          do_assignment(instructions, state,
1754                        this->subexpressions[0]->non_lvalue_description,
1755                        op[0]->clone(ctx, NULL), temp_rhs,
1756                        &result, needs_rvalue, false,
1757                        this->subexpressions[0]->get_location());
1758       break;
1759    }
1760 
1761    case ast_and_assign:
1762    case ast_xor_assign:
1763    case ast_or_assign: {
1764       this->subexpressions[0]->set_is_lhs(true);
1765       op[0] = this->subexpressions[0]->hir(instructions, state);
1766       op[1] = this->subexpressions[1]->hir(instructions, state);
1767 
1768       orig_type = op[0]->type;
1769       type = bit_logic_result_type(op[0], op[1], this->oper, state, &loc);
1770 
1771       if (type != orig_type) {
1772          _mesa_glsl_error(& loc, state,
1773                           "could not implicitly convert "
1774                           "%s to %s", type->name, orig_type->name);
1775          type = glsl_type::error_type;
1776       }
1777 
1778       ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper],
1779                                                    type, op[0], op[1]);
1780       error_emitted =
1781          do_assignment(instructions, state,
1782                        this->subexpressions[0]->non_lvalue_description,
1783                        op[0]->clone(ctx, NULL), temp_rhs,
1784                        &result, needs_rvalue, false,
1785                        this->subexpressions[0]->get_location());
1786       break;
1787    }
1788 
1789    case ast_conditional: {
1790       /* From page 59 (page 65 of the PDF) of the GLSL 1.50 spec:
1791        *
1792        *    "The ternary selection operator (?:). It operates on three
1793        *    expressions (exp1 ? exp2 : exp3). This operator evaluates the
1794        *    first expression, which must result in a scalar Boolean."
1795        */
1796       op[0] = get_scalar_boolean_operand(instructions, state, this, 0,
1797                                          "condition", &error_emitted);
1798 
1799       /* The :? operator is implemented by generating an anonymous temporary
1800        * followed by an if-statement.  The last instruction in each branch of
1801        * the if-statement assigns a value to the anonymous temporary.  This
1802        * temporary is the r-value of the expression.
1803        */
1804       exec_list then_instructions;
1805       exec_list else_instructions;
1806 
1807       op[1] = this->subexpressions[1]->hir(&then_instructions, state);
1808       op[2] = this->subexpressions[2]->hir(&else_instructions, state);
1809 
1810       /* From page 59 (page 65 of the PDF) of the GLSL 1.50 spec:
1811        *
1812        *     "The second and third expressions can be any type, as
1813        *     long their types match, or there is a conversion in
1814        *     Section 4.1.10 "Implicit Conversions" that can be applied
1815        *     to one of the expressions to make their types match. This
1816        *     resulting matching type is the type of the entire
1817        *     expression."
1818        */
1819       if ((!apply_implicit_conversion(op[1]->type, op[2], state)
1820           && !apply_implicit_conversion(op[2]->type, op[1], state))
1821           || (op[1]->type != op[2]->type)) {
1822          YYLTYPE loc = this->subexpressions[1]->get_location();
1823 
1824          _mesa_glsl_error(& loc, state, "second and third operands of ?: "
1825                           "operator must have matching types");
1826          error_emitted = true;
1827          type = glsl_type::error_type;
1828       } else {
1829          type = op[1]->type;
1830       }
1831 
1832       /* From page 33 (page 39 of the PDF) of the GLSL 1.10 spec:
1833        *
1834        *    "The second and third expressions must be the same type, but can
1835        *    be of any type other than an array."
1836        */
1837       if (type->is_array() &&
1838           !state->check_version(120, 300, &loc,
1839                                 "second and third operands of ?: operator "
1840                                 "cannot be arrays")) {
1841          error_emitted = true;
1842       }
1843 
1844       /* From section 4.1.7 of the GLSL 4.50 spec (Opaque Types):
1845        *
1846        *  "Except for array indexing, structure member selection, and
1847        *   parentheses, opaque variables are not allowed to be operands in
1848        *   expressions; such use results in a compile-time error."
1849        */
1850       if (type->contains_opaque()) {
1851          _mesa_glsl_error(&loc, state, "opaque variables cannot be operands "
1852                           "of the ?: operator");
1853          error_emitted = true;
1854       }
1855 
1856       ir_constant *cond_val = op[0]->constant_expression_value(ctx);
1857 
1858       if (then_instructions.is_empty()
1859           && else_instructions.is_empty()
1860           && cond_val != NULL) {
1861          result = cond_val->value.b[0] ? op[1] : op[2];
1862       } else {
1863          /* The copy to conditional_tmp reads the whole array. */
1864          if (type->is_array()) {
1865             mark_whole_array_access(op[1]);
1866             mark_whole_array_access(op[2]);
1867          }
1868 
1869          ir_variable *const tmp =
1870             new(ctx) ir_variable(type, "conditional_tmp", ir_var_temporary);
1871          instructions->push_tail(tmp);
1872 
1873          ir_if *const stmt = new(ctx) ir_if(op[0]);
1874          instructions->push_tail(stmt);
1875 
1876          then_instructions.move_nodes_to(& stmt->then_instructions);
1877          ir_dereference *const then_deref =
1878             new(ctx) ir_dereference_variable(tmp);
1879          ir_assignment *const then_assign =
1880             new(ctx) ir_assignment(then_deref, op[1]);
1881          stmt->then_instructions.push_tail(then_assign);
1882 
1883          else_instructions.move_nodes_to(& stmt->else_instructions);
1884          ir_dereference *const else_deref =
1885             new(ctx) ir_dereference_variable(tmp);
1886          ir_assignment *const else_assign =
1887             new(ctx) ir_assignment(else_deref, op[2]);
1888          stmt->else_instructions.push_tail(else_assign);
1889 
1890          result = new(ctx) ir_dereference_variable(tmp);
1891       }
1892       break;
1893    }
1894 
1895    case ast_pre_inc:
1896    case ast_pre_dec: {
1897       this->non_lvalue_description = (this->oper == ast_pre_inc)
1898          ? "pre-increment operation" : "pre-decrement operation";
1899 
1900       op[0] = this->subexpressions[0]->hir(instructions, state);
1901       op[1] = constant_one_for_inc_dec(ctx, op[0]->type);
1902 
1903       type = arithmetic_result_type(op[0], op[1], false, state, & loc);
1904 
1905       ir_rvalue *temp_rhs;
1906       temp_rhs = new(ctx) ir_expression(operations[this->oper], type,
1907                                         op[0], op[1]);
1908 
1909       error_emitted =
1910          do_assignment(instructions, state,
1911                        this->subexpressions[0]->non_lvalue_description,
1912                        op[0]->clone(ctx, NULL), temp_rhs,
1913                        &result, needs_rvalue, false,
1914                        this->subexpressions[0]->get_location());
1915       break;
1916    }
1917 
1918    case ast_post_inc:
1919    case ast_post_dec: {
1920       this->non_lvalue_description = (this->oper == ast_post_inc)
1921          ? "post-increment operation" : "post-decrement operation";
1922       op[0] = this->subexpressions[0]->hir(instructions, state);
1923       op[1] = constant_one_for_inc_dec(ctx, op[0]->type);
1924 
1925       error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1926 
1927       type = arithmetic_result_type(op[0], op[1], false, state, & loc);
1928 
1929       ir_rvalue *temp_rhs;
1930       temp_rhs = new(ctx) ir_expression(operations[this->oper], type,
1931                                         op[0], op[1]);
1932 
1933       /* Get a temporary of a copy of the lvalue before it's modified.
1934        * This may get thrown away later.
1935        */
1936       result = get_lvalue_copy(instructions, op[0]->clone(ctx, NULL));
1937 
1938       ir_rvalue *junk_rvalue;
1939       error_emitted =
1940          do_assignment(instructions, state,
1941                        this->subexpressions[0]->non_lvalue_description,
1942                        op[0]->clone(ctx, NULL), temp_rhs,
1943                        &junk_rvalue, false, false,
1944                        this->subexpressions[0]->get_location());
1945 
1946       break;
1947    }
1948 
1949    case ast_field_selection:
1950       result = _mesa_ast_field_selection_to_hir(this, instructions, state);
1951       break;
1952 
1953    case ast_array_index: {
1954       YYLTYPE index_loc = subexpressions[1]->get_location();
1955 
1956       /* Getting if an array is being used uninitialized is beyond what we get
1957        * from ir_value.data.assigned. Setting is_lhs as true would force to
1958        * not raise a uninitialized warning when using an array
1959        */
1960       subexpressions[0]->set_is_lhs(true);
1961       op[0] = subexpressions[0]->hir(instructions, state);
1962       op[1] = subexpressions[1]->hir(instructions, state);
1963 
1964       result = _mesa_ast_array_index_to_hir(ctx, state, op[0], op[1],
1965                                             loc, index_loc);
1966 
1967       if (result->type->is_error())
1968          error_emitted = true;
1969 
1970       break;
1971    }
1972 
1973    case ast_unsized_array_dim:
1974       assert(!"ast_unsized_array_dim: Should never get here.");
1975       break;
1976 
1977    case ast_function_call:
1978       /* Should *NEVER* get here.  ast_function_call should always be handled
1979        * by ast_function_expression::hir.
1980        */
1981       assert(0);
1982       break;
1983 
1984    case ast_identifier: {
1985       /* ast_identifier can appear several places in a full abstract syntax
1986        * tree.  This particular use must be at location specified in the grammar
1987        * as 'variable_identifier'.
1988        */
1989       ir_variable *var =
1990          state->symbols->get_variable(this->primary_expression.identifier);
1991 
1992       if (var == NULL) {
1993          /* the identifier might be a subroutine name */
1994          char *sub_name;
1995          sub_name = ralloc_asprintf(ctx, "%s_%s", _mesa_shader_stage_to_subroutine_prefix(state->stage), this->primary_expression.identifier);
1996          var = state->symbols->get_variable(sub_name);
1997          ralloc_free(sub_name);
1998       }
1999 
2000       if (var != NULL) {
2001          var->data.used = true;
2002          result = new(ctx) ir_dereference_variable(var);
2003 
2004          if ((var->data.mode == ir_var_auto || var->data.mode == ir_var_shader_out)
2005              && !this->is_lhs
2006              && result->variable_referenced()->data.assigned != true
2007              && !is_gl_identifier(var->name)) {
2008             _mesa_glsl_warning(&loc, state, "`%s' used uninitialized",
2009                                this->primary_expression.identifier);
2010          }
2011       } else {
2012          _mesa_glsl_error(& loc, state, "`%s' undeclared",
2013                           this->primary_expression.identifier);
2014 
2015          result = ir_rvalue::error_value(ctx);
2016          error_emitted = true;
2017       }
2018       break;
2019    }
2020 
2021    case ast_int_constant:
2022       result = new(ctx) ir_constant(this->primary_expression.int_constant);
2023       break;
2024 
2025    case ast_uint_constant:
2026       result = new(ctx) ir_constant(this->primary_expression.uint_constant);
2027       break;
2028 
2029    case ast_float_constant:
2030       result = new(ctx) ir_constant(this->primary_expression.float_constant);
2031       break;
2032 
2033    case ast_bool_constant:
2034       result = new(ctx) ir_constant(bool(this->primary_expression.bool_constant));
2035       break;
2036 
2037    case ast_double_constant:
2038       result = new(ctx) ir_constant(this->primary_expression.double_constant);
2039       break;
2040 
2041    case ast_uint64_constant:
2042       result = new(ctx) ir_constant(this->primary_expression.uint64_constant);
2043       break;
2044 
2045    case ast_int64_constant:
2046       result = new(ctx) ir_constant(this->primary_expression.int64_constant);
2047       break;
2048 
2049    case ast_sequence: {
2050       /* It should not be possible to generate a sequence in the AST without
2051        * any expressions in it.
2052        */
2053       assert(!this->expressions.is_empty());
2054 
2055       /* The r-value of a sequence is the last expression in the sequence.  If
2056        * the other expressions in the sequence do not have side-effects (and
2057        * therefore add instructions to the instruction list), they get dropped
2058        * on the floor.
2059        */
2060       exec_node *previous_tail = NULL;
2061       YYLTYPE previous_operand_loc = loc;
2062 
2063       foreach_list_typed (ast_node, ast, link, &this->expressions) {
2064          /* If one of the operands of comma operator does not generate any
2065           * code, we want to emit a warning.  At each pass through the loop
2066           * previous_tail will point to the last instruction in the stream
2067           * *before* processing the previous operand.  Naturally,
2068           * instructions->get_tail_raw() will point to the last instruction in
2069           * the stream *after* processing the previous operand.  If the two
2070           * pointers match, then the previous operand had no effect.
2071           *
2072           * The warning behavior here differs slightly from GCC.  GCC will
2073           * only emit a warning if none of the left-hand operands have an
2074           * effect.  However, it will emit a warning for each.  I believe that
2075           * there are some cases in C (especially with GCC extensions) where
2076           * it is useful to have an intermediate step in a sequence have no
2077           * effect, but I don't think these cases exist in GLSL.  Either way,
2078           * it would be a giant hassle to replicate that behavior.
2079           */
2080          if (previous_tail == instructions->get_tail_raw()) {
2081             _mesa_glsl_warning(&previous_operand_loc, state,
2082                                "left-hand operand of comma expression has "
2083                                "no effect");
2084          }
2085 
2086          /* The tail is directly accessed instead of using the get_tail()
2087           * method for performance reasons.  get_tail() has extra code to
2088           * return NULL when the list is empty.  We don't care about that
2089           * here, so using get_tail_raw() is fine.
2090           */
2091          previous_tail = instructions->get_tail_raw();
2092          previous_operand_loc = ast->get_location();
2093 
2094          result = ast->hir(instructions, state);
2095       }
2096 
2097       /* Any errors should have already been emitted in the loop above.
2098        */
2099       error_emitted = true;
2100       break;
2101    }
2102    }
2103    type = NULL; /* use result->type, not type. */
2104    assert(result != NULL || !needs_rvalue);
2105 
2106    if (result && result->type->is_error() && !error_emitted)
2107       _mesa_glsl_error(& loc, state, "type mismatch");
2108 
2109    return result;
2110 }
2111 
2112 bool
has_sequence_subexpression() const2113 ast_expression::has_sequence_subexpression() const
2114 {
2115    switch (this->oper) {
2116    case ast_plus:
2117    case ast_neg:
2118    case ast_bit_not:
2119    case ast_logic_not:
2120    case ast_pre_inc:
2121    case ast_pre_dec:
2122    case ast_post_inc:
2123    case ast_post_dec:
2124       return this->subexpressions[0]->has_sequence_subexpression();
2125 
2126    case ast_assign:
2127    case ast_add:
2128    case ast_sub:
2129    case ast_mul:
2130    case ast_div:
2131    case ast_mod:
2132    case ast_lshift:
2133    case ast_rshift:
2134    case ast_less:
2135    case ast_greater:
2136    case ast_lequal:
2137    case ast_gequal:
2138    case ast_nequal:
2139    case ast_equal:
2140    case ast_bit_and:
2141    case ast_bit_xor:
2142    case ast_bit_or:
2143    case ast_logic_and:
2144    case ast_logic_or:
2145    case ast_logic_xor:
2146    case ast_array_index:
2147    case ast_mul_assign:
2148    case ast_div_assign:
2149    case ast_add_assign:
2150    case ast_sub_assign:
2151    case ast_mod_assign:
2152    case ast_ls_assign:
2153    case ast_rs_assign:
2154    case ast_and_assign:
2155    case ast_xor_assign:
2156    case ast_or_assign:
2157       return this->subexpressions[0]->has_sequence_subexpression() ||
2158              this->subexpressions[1]->has_sequence_subexpression();
2159 
2160    case ast_conditional:
2161       return this->subexpressions[0]->has_sequence_subexpression() ||
2162              this->subexpressions[1]->has_sequence_subexpression() ||
2163              this->subexpressions[2]->has_sequence_subexpression();
2164 
2165    case ast_sequence:
2166       return true;
2167 
2168    case ast_field_selection:
2169    case ast_identifier:
2170    case ast_int_constant:
2171    case ast_uint_constant:
2172    case ast_float_constant:
2173    case ast_bool_constant:
2174    case ast_double_constant:
2175    case ast_int64_constant:
2176    case ast_uint64_constant:
2177       return false;
2178 
2179    case ast_aggregate:
2180       return false;
2181 
2182    case ast_function_call:
2183       unreachable("should be handled by ast_function_expression::hir");
2184 
2185    case ast_unsized_array_dim:
2186       unreachable("ast_unsized_array_dim: Should never get here.");
2187    }
2188 
2189    return false;
2190 }
2191 
2192 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)2193 ast_expression_statement::hir(exec_list *instructions,
2194                               struct _mesa_glsl_parse_state *state)
2195 {
2196    /* It is possible to have expression statements that don't have an
2197     * expression.  This is the solitary semicolon:
2198     *
2199     * for (i = 0; i < 5; i++)
2200     *     ;
2201     *
2202     * In this case the expression will be NULL.  Test for NULL and don't do
2203     * anything in that case.
2204     */
2205    if (expression != NULL)
2206       expression->hir_no_rvalue(instructions, state);
2207 
2208    /* Statements do not have r-values.
2209     */
2210    return NULL;
2211 }
2212 
2213 
2214 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)2215 ast_compound_statement::hir(exec_list *instructions,
2216                             struct _mesa_glsl_parse_state *state)
2217 {
2218    if (new_scope)
2219       state->symbols->push_scope();
2220 
2221    foreach_list_typed (ast_node, ast, link, &this->statements)
2222       ast->hir(instructions, state);
2223 
2224    if (new_scope)
2225       state->symbols->pop_scope();
2226 
2227    /* Compound statements do not have r-values.
2228     */
2229    return NULL;
2230 }
2231 
2232 /**
2233  * Evaluate the given exec_node (which should be an ast_node representing
2234  * a single array dimension) and return its integer value.
2235  */
2236 static unsigned
process_array_size(exec_node * node,struct _mesa_glsl_parse_state * state)2237 process_array_size(exec_node *node,
2238                    struct _mesa_glsl_parse_state *state)
2239 {
2240    void *mem_ctx = state;
2241 
2242    exec_list dummy_instructions;
2243 
2244    ast_node *array_size = exec_node_data(ast_node, node, link);
2245 
2246    /**
2247     * Dimensions other than the outermost dimension can by unsized if they
2248     * are immediately sized by a constructor or initializer.
2249     */
2250    if (((ast_expression*)array_size)->oper == ast_unsized_array_dim)
2251       return 0;
2252 
2253    ir_rvalue *const ir = array_size->hir(& dummy_instructions, state);
2254    YYLTYPE loc = array_size->get_location();
2255 
2256    if (ir == NULL) {
2257       _mesa_glsl_error(& loc, state,
2258                        "array size could not be resolved");
2259       return 0;
2260    }
2261 
2262    if (!ir->type->is_integer()) {
2263       _mesa_glsl_error(& loc, state,
2264                        "array size must be integer type");
2265       return 0;
2266    }
2267 
2268    if (!ir->type->is_scalar()) {
2269       _mesa_glsl_error(& loc, state,
2270                        "array size must be scalar type");
2271       return 0;
2272    }
2273 
2274    ir_constant *const size = ir->constant_expression_value(mem_ctx);
2275    if (size == NULL ||
2276        (state->is_version(120, 300) &&
2277         array_size->has_sequence_subexpression())) {
2278       _mesa_glsl_error(& loc, state, "array size must be a "
2279                        "constant valued expression");
2280       return 0;
2281    }
2282 
2283    if (size->value.i[0] <= 0) {
2284       _mesa_glsl_error(& loc, state, "array size must be > 0");
2285       return 0;
2286    }
2287 
2288    assert(size->type == ir->type);
2289 
2290    /* If the array size is const (and we've verified that
2291     * it is) then no instructions should have been emitted
2292     * when we converted it to HIR. If they were emitted,
2293     * then either the array size isn't const after all, or
2294     * we are emitting unnecessary instructions.
2295     */
2296    assert(dummy_instructions.is_empty());
2297 
2298    return size->value.u[0];
2299 }
2300 
2301 static const glsl_type *
process_array_type(YYLTYPE * loc,const glsl_type * base,ast_array_specifier * array_specifier,struct _mesa_glsl_parse_state * state)2302 process_array_type(YYLTYPE *loc, const glsl_type *base,
2303                    ast_array_specifier *array_specifier,
2304                    struct _mesa_glsl_parse_state *state)
2305 {
2306    const glsl_type *array_type = base;
2307 
2308    if (array_specifier != NULL) {
2309       if (base->is_array()) {
2310 
2311          /* From page 19 (page 25) of the GLSL 1.20 spec:
2312           *
2313           * "Only one-dimensional arrays may be declared."
2314           */
2315          if (!state->check_arrays_of_arrays_allowed(loc)) {
2316             return glsl_type::error_type;
2317          }
2318       }
2319 
2320       for (exec_node *node = array_specifier->array_dimensions.get_tail_raw();
2321            !node->is_head_sentinel(); node = node->prev) {
2322          unsigned array_size = process_array_size(node, state);
2323          array_type = glsl_type::get_array_instance(array_type, array_size);
2324       }
2325    }
2326 
2327    return array_type;
2328 }
2329 
2330 static bool
precision_qualifier_allowed(const glsl_type * type)2331 precision_qualifier_allowed(const glsl_type *type)
2332 {
2333    /* Precision qualifiers apply to floating point, integer and opaque
2334     * types.
2335     *
2336     * Section 4.5.2 (Precision Qualifiers) of the GLSL 1.30 spec says:
2337     *    "Any floating point or any integer declaration can have the type
2338     *    preceded by one of these precision qualifiers [...] Literal
2339     *    constants do not have precision qualifiers. Neither do Boolean
2340     *    variables.
2341     *
2342     * Section 4.5 (Precision and Precision Qualifiers) of the GLSL 1.30
2343     * spec also says:
2344     *
2345     *     "Precision qualifiers are added for code portability with OpenGL
2346     *     ES, not for functionality. They have the same syntax as in OpenGL
2347     *     ES."
2348     *
2349     * Section 8 (Built-In Functions) of the GLSL ES 1.00 spec says:
2350     *
2351     *     "uniform lowp sampler2D sampler;
2352     *     highp vec2 coord;
2353     *     ...
2354     *     lowp vec4 col = texture2D (sampler, coord);
2355     *                                            // texture2D returns lowp"
2356     *
2357     * From this, we infer that GLSL 1.30 (and later) should allow precision
2358     * qualifiers on sampler types just like float and integer types.
2359     */
2360    const glsl_type *const t = type->without_array();
2361 
2362    return (t->is_float() || t->is_integer() || t->contains_opaque()) &&
2363           !t->is_record();
2364 }
2365 
2366 const glsl_type *
glsl_type(const char ** name,struct _mesa_glsl_parse_state * state) const2367 ast_type_specifier::glsl_type(const char **name,
2368                               struct _mesa_glsl_parse_state *state) const
2369 {
2370    const struct glsl_type *type;
2371 
2372    if (this->type != NULL)
2373       type = this->type;
2374    else if (structure)
2375       type = structure->type;
2376    else
2377       type = state->symbols->get_type(this->type_name);
2378    *name = this->type_name;
2379 
2380    YYLTYPE loc = this->get_location();
2381    type = process_array_type(&loc, type, this->array_specifier, state);
2382 
2383    return type;
2384 }
2385 
2386 /**
2387  * From the OpenGL ES 3.0 spec, 4.5.4 Default Precision Qualifiers:
2388  *
2389  * "The precision statement
2390  *
2391  *    precision precision-qualifier type;
2392  *
2393  *  can be used to establish a default precision qualifier. The type field can
2394  *  be either int or float or any of the sampler types, (...) If type is float,
2395  *  the directive applies to non-precision-qualified floating point type
2396  *  (scalar, vector, and matrix) declarations. If type is int, the directive
2397  *  applies to all non-precision-qualified integer type (scalar, vector, signed,
2398  *  and unsigned) declarations."
2399  *
2400  * We use the symbol table to keep the values of the default precisions for
2401  * each 'type' in each scope and we use the 'type' string from the precision
2402  * statement as key in the symbol table. When we want to retrieve the default
2403  * precision associated with a given glsl_type we need to know the type string
2404  * associated with it. This is what this function returns.
2405  */
2406 static const char *
get_type_name_for_precision_qualifier(const glsl_type * type)2407 get_type_name_for_precision_qualifier(const glsl_type *type)
2408 {
2409    switch (type->base_type) {
2410    case GLSL_TYPE_FLOAT:
2411       return "float";
2412    case GLSL_TYPE_UINT:
2413    case GLSL_TYPE_INT:
2414       return "int";
2415    case GLSL_TYPE_ATOMIC_UINT:
2416       return "atomic_uint";
2417    case GLSL_TYPE_IMAGE:
2418    /* fallthrough */
2419    case GLSL_TYPE_SAMPLER: {
2420       const unsigned type_idx =
2421          type->sampler_array + 2 * type->sampler_shadow;
2422       const unsigned offset = type->is_sampler() ? 0 : 4;
2423       assert(type_idx < 4);
2424       switch (type->sampled_type) {
2425       case GLSL_TYPE_FLOAT:
2426          switch (type->sampler_dimensionality) {
2427          case GLSL_SAMPLER_DIM_1D: {
2428             assert(type->is_sampler());
2429             static const char *const names[4] = {
2430               "sampler1D", "sampler1DArray",
2431               "sampler1DShadow", "sampler1DArrayShadow"
2432             };
2433             return names[type_idx];
2434          }
2435          case GLSL_SAMPLER_DIM_2D: {
2436             static const char *const names[8] = {
2437               "sampler2D", "sampler2DArray",
2438               "sampler2DShadow", "sampler2DArrayShadow",
2439               "image2D", "image2DArray", NULL, NULL
2440             };
2441             return names[offset + type_idx];
2442          }
2443          case GLSL_SAMPLER_DIM_3D: {
2444             static const char *const names[8] = {
2445               "sampler3D", NULL, NULL, NULL,
2446               "image3D", NULL, NULL, NULL
2447             };
2448             return names[offset + type_idx];
2449          }
2450          case GLSL_SAMPLER_DIM_CUBE: {
2451             static const char *const names[8] = {
2452               "samplerCube", "samplerCubeArray",
2453               "samplerCubeShadow", "samplerCubeArrayShadow",
2454               "imageCube", NULL, NULL, NULL
2455             };
2456             return names[offset + type_idx];
2457          }
2458          case GLSL_SAMPLER_DIM_MS: {
2459             assert(type->is_sampler());
2460             static const char *const names[4] = {
2461               "sampler2DMS", "sampler2DMSArray", NULL, NULL
2462             };
2463             return names[type_idx];
2464          }
2465          case GLSL_SAMPLER_DIM_RECT: {
2466             assert(type->is_sampler());
2467             static const char *const names[4] = {
2468               "samplerRect", NULL, "samplerRectShadow", NULL
2469             };
2470             return names[type_idx];
2471          }
2472          case GLSL_SAMPLER_DIM_BUF: {
2473             static const char *const names[8] = {
2474               "samplerBuffer", NULL, NULL, NULL,
2475               "imageBuffer", NULL, NULL, NULL
2476             };
2477             return names[offset + type_idx];
2478          }
2479          case GLSL_SAMPLER_DIM_EXTERNAL: {
2480             assert(type->is_sampler());
2481             static const char *const names[4] = {
2482               "samplerExternalOES", NULL, NULL, NULL
2483             };
2484             return names[type_idx];
2485          }
2486          default:
2487             unreachable("Unsupported sampler/image dimensionality");
2488          } /* sampler/image float dimensionality */
2489          break;
2490       case GLSL_TYPE_INT:
2491          switch (type->sampler_dimensionality) {
2492          case GLSL_SAMPLER_DIM_1D: {
2493             assert(type->is_sampler());
2494             static const char *const names[4] = {
2495               "isampler1D", "isampler1DArray", NULL, NULL
2496             };
2497             return names[type_idx];
2498          }
2499          case GLSL_SAMPLER_DIM_2D: {
2500             static const char *const names[8] = {
2501               "isampler2D", "isampler2DArray", NULL, NULL,
2502               "iimage2D", "iimage2DArray", NULL, NULL
2503             };
2504             return names[offset + type_idx];
2505          }
2506          case GLSL_SAMPLER_DIM_3D: {
2507             static const char *const names[8] = {
2508               "isampler3D", NULL, NULL, NULL,
2509               "iimage3D", NULL, NULL, NULL
2510             };
2511             return names[offset + type_idx];
2512          }
2513          case GLSL_SAMPLER_DIM_CUBE: {
2514             static const char *const names[8] = {
2515               "isamplerCube", "isamplerCubeArray", NULL, NULL,
2516               "iimageCube", NULL, NULL, NULL
2517             };
2518             return names[offset + type_idx];
2519          }
2520          case GLSL_SAMPLER_DIM_MS: {
2521             assert(type->is_sampler());
2522             static const char *const names[4] = {
2523               "isampler2DMS", "isampler2DMSArray", NULL, NULL
2524             };
2525             return names[type_idx];
2526          }
2527          case GLSL_SAMPLER_DIM_RECT: {
2528             assert(type->is_sampler());
2529             static const char *const names[4] = {
2530               "isamplerRect", NULL, "isamplerRectShadow", NULL
2531             };
2532             return names[type_idx];
2533          }
2534          case GLSL_SAMPLER_DIM_BUF: {
2535             static const char *const names[8] = {
2536               "isamplerBuffer", NULL, NULL, NULL,
2537               "iimageBuffer", NULL, NULL, NULL
2538             };
2539             return names[offset + type_idx];
2540          }
2541          default:
2542             unreachable("Unsupported isampler/iimage dimensionality");
2543          } /* sampler/image int dimensionality */
2544          break;
2545       case GLSL_TYPE_UINT:
2546          switch (type->sampler_dimensionality) {
2547          case GLSL_SAMPLER_DIM_1D: {
2548             assert(type->is_sampler());
2549             static const char *const names[4] = {
2550               "usampler1D", "usampler1DArray", NULL, NULL
2551             };
2552             return names[type_idx];
2553          }
2554          case GLSL_SAMPLER_DIM_2D: {
2555             static const char *const names[8] = {
2556               "usampler2D", "usampler2DArray", NULL, NULL,
2557               "uimage2D", "uimage2DArray", NULL, NULL
2558             };
2559             return names[offset + type_idx];
2560          }
2561          case GLSL_SAMPLER_DIM_3D: {
2562             static const char *const names[8] = {
2563               "usampler3D", NULL, NULL, NULL,
2564               "uimage3D", NULL, NULL, NULL
2565             };
2566             return names[offset + type_idx];
2567          }
2568          case GLSL_SAMPLER_DIM_CUBE: {
2569             static const char *const names[8] = {
2570               "usamplerCube", "usamplerCubeArray", NULL, NULL,
2571               "uimageCube", NULL, NULL, NULL
2572             };
2573             return names[offset + type_idx];
2574          }
2575          case GLSL_SAMPLER_DIM_MS: {
2576             assert(type->is_sampler());
2577             static const char *const names[4] = {
2578               "usampler2DMS", "usampler2DMSArray", NULL, NULL
2579             };
2580             return names[type_idx];
2581          }
2582          case GLSL_SAMPLER_DIM_RECT: {
2583             assert(type->is_sampler());
2584             static const char *const names[4] = {
2585               "usamplerRect", NULL, "usamplerRectShadow", NULL
2586             };
2587             return names[type_idx];
2588          }
2589          case GLSL_SAMPLER_DIM_BUF: {
2590             static const char *const names[8] = {
2591               "usamplerBuffer", NULL, NULL, NULL,
2592               "uimageBuffer", NULL, NULL, NULL
2593             };
2594             return names[offset + type_idx];
2595          }
2596          default:
2597             unreachable("Unsupported usampler/uimage dimensionality");
2598          } /* sampler/image uint dimensionality */
2599          break;
2600       default:
2601          unreachable("Unsupported sampler/image type");
2602       } /* sampler/image type */
2603       break;
2604    } /* GLSL_TYPE_SAMPLER/GLSL_TYPE_IMAGE */
2605    break;
2606    default:
2607       unreachable("Unsupported type");
2608    } /* base type */
2609 }
2610 
2611 static unsigned
select_gles_precision(unsigned qual_precision,const glsl_type * type,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)2612 select_gles_precision(unsigned qual_precision,
2613                       const glsl_type *type,
2614                       struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
2615 {
2616    /* Precision qualifiers do not have any meaning in Desktop GLSL.
2617     * In GLES we take the precision from the type qualifier if present,
2618     * otherwise, if the type of the variable allows precision qualifiers at
2619     * all, we look for the default precision qualifier for that type in the
2620     * current scope.
2621     */
2622    assert(state->es_shader);
2623 
2624    unsigned precision = GLSL_PRECISION_NONE;
2625    if (qual_precision) {
2626       precision = qual_precision;
2627    } else if (precision_qualifier_allowed(type)) {
2628       const char *type_name =
2629          get_type_name_for_precision_qualifier(type->without_array());
2630       assert(type_name != NULL);
2631 
2632       precision =
2633          state->symbols->get_default_precision_qualifier(type_name);
2634       if (precision == ast_precision_none) {
2635          _mesa_glsl_error(loc, state,
2636                           "No precision specified in this scope for type `%s'",
2637                           type->name);
2638       }
2639    }
2640 
2641 
2642    /* Section 4.1.7.3 (Atomic Counters) of the GLSL ES 3.10 spec says:
2643     *
2644     *    "The default precision of all atomic types is highp. It is an error to
2645     *    declare an atomic type with a different precision or to specify the
2646     *    default precision for an atomic type to be lowp or mediump."
2647     */
2648    if (type->is_atomic_uint() && precision != ast_precision_high) {
2649       _mesa_glsl_error(loc, state,
2650                        "atomic_uint can only have highp precision qualifier");
2651    }
2652 
2653    return precision;
2654 }
2655 
2656 const glsl_type *
glsl_type(const char ** name,struct _mesa_glsl_parse_state * state) const2657 ast_fully_specified_type::glsl_type(const char **name,
2658                                     struct _mesa_glsl_parse_state *state) const
2659 {
2660    return this->specifier->glsl_type(name, state);
2661 }
2662 
2663 /**
2664  * Determine whether a toplevel variable declaration declares a varying.  This
2665  * function operates by examining the variable's mode and the shader target,
2666  * so it correctly identifies linkage variables regardless of whether they are
2667  * declared using the deprecated "varying" syntax or the new "in/out" syntax.
2668  *
2669  * Passing a non-toplevel variable declaration (e.g. a function parameter) to
2670  * this function will produce undefined results.
2671  */
2672 static bool
is_varying_var(ir_variable * var,gl_shader_stage target)2673 is_varying_var(ir_variable *var, gl_shader_stage target)
2674 {
2675    switch (target) {
2676    case MESA_SHADER_VERTEX:
2677       return var->data.mode == ir_var_shader_out;
2678    case MESA_SHADER_FRAGMENT:
2679       return var->data.mode == ir_var_shader_in;
2680    default:
2681       return var->data.mode == ir_var_shader_out || var->data.mode == ir_var_shader_in;
2682    }
2683 }
2684 
2685 static bool
is_allowed_invariant(ir_variable * var,struct _mesa_glsl_parse_state * state)2686 is_allowed_invariant(ir_variable *var, struct _mesa_glsl_parse_state *state)
2687 {
2688    if (is_varying_var(var, state->stage))
2689       return true;
2690 
2691    /* From Section 4.6.1 ("The Invariant Qualifier") GLSL 1.20 spec:
2692     * "Only variables output from a vertex shader can be candidates
2693     * for invariance".
2694     */
2695    if (!state->is_version(130, 0))
2696       return false;
2697 
2698    /*
2699     * Later specs remove this language - so allowed invariant
2700     * on fragment shader outputs as well.
2701     */
2702    if (state->stage == MESA_SHADER_FRAGMENT &&
2703        var->data.mode == ir_var_shader_out)
2704       return true;
2705    return false;
2706 }
2707 
2708 /**
2709  * Matrix layout qualifiers are only allowed on certain types
2710  */
2711 static void
validate_matrix_layout_for_type(struct _mesa_glsl_parse_state * state,YYLTYPE * loc,const glsl_type * type,ir_variable * var)2712 validate_matrix_layout_for_type(struct _mesa_glsl_parse_state *state,
2713                                 YYLTYPE *loc,
2714                                 const glsl_type *type,
2715                                 ir_variable *var)
2716 {
2717    if (var && !var->is_in_buffer_block()) {
2718       /* Layout qualifiers may only apply to interface blocks and fields in
2719        * them.
2720        */
2721       _mesa_glsl_error(loc, state,
2722                        "uniform block layout qualifiers row_major and "
2723                        "column_major may not be applied to variables "
2724                        "outside of uniform blocks");
2725    } else if (!type->without_array()->is_matrix()) {
2726       /* The OpenGL ES 3.0 conformance tests did not originally allow
2727        * matrix layout qualifiers on non-matrices.  However, the OpenGL
2728        * 4.4 and OpenGL ES 3.0 (revision TBD) specifications were
2729        * amended to specifically allow these layouts on all types.  Emit
2730        * a warning so that people know their code may not be portable.
2731        */
2732       _mesa_glsl_warning(loc, state,
2733                          "uniform block layout qualifiers row_major and "
2734                          "column_major applied to non-matrix types may "
2735                          "be rejected by older compilers");
2736    }
2737 }
2738 
2739 static bool
validate_xfb_buffer_qualifier(YYLTYPE * loc,struct _mesa_glsl_parse_state * state,unsigned xfb_buffer)2740 validate_xfb_buffer_qualifier(YYLTYPE *loc,
2741                               struct _mesa_glsl_parse_state *state,
2742                               unsigned xfb_buffer) {
2743    if (xfb_buffer >= state->Const.MaxTransformFeedbackBuffers) {
2744       _mesa_glsl_error(loc, state,
2745                        "invalid xfb_buffer specified %d is larger than "
2746                        "MAX_TRANSFORM_FEEDBACK_BUFFERS - 1 (%d).",
2747                        xfb_buffer,
2748                        state->Const.MaxTransformFeedbackBuffers - 1);
2749       return false;
2750    }
2751 
2752    return true;
2753 }
2754 
2755 /* From the ARB_enhanced_layouts spec:
2756  *
2757  *    "Variables and block members qualified with *xfb_offset* can be
2758  *    scalars, vectors, matrices, structures, and (sized) arrays of these.
2759  *    The offset must be a multiple of the size of the first component of
2760  *    the first qualified variable or block member, or a compile-time error
2761  *    results.  Further, if applied to an aggregate containing a double,
2762  *    the offset must also be a multiple of 8, and the space taken in the
2763  *    buffer will be a multiple of 8.
2764  */
2765 static bool
validate_xfb_offset_qualifier(YYLTYPE * loc,struct _mesa_glsl_parse_state * state,int xfb_offset,const glsl_type * type,unsigned component_size)2766 validate_xfb_offset_qualifier(YYLTYPE *loc,
2767                               struct _mesa_glsl_parse_state *state,
2768                               int xfb_offset, const glsl_type *type,
2769                               unsigned component_size) {
2770   const glsl_type *t_without_array = type->without_array();
2771 
2772    if (xfb_offset != -1 && type->is_unsized_array()) {
2773       _mesa_glsl_error(loc, state,
2774                        "xfb_offset can't be used with unsized arrays.");
2775       return false;
2776    }
2777 
2778    /* Make sure nested structs don't contain unsized arrays, and validate
2779     * any xfb_offsets on interface members.
2780     */
2781    if (t_without_array->is_record() || t_without_array->is_interface())
2782       for (unsigned int i = 0; i < t_without_array->length; i++) {
2783          const glsl_type *member_t = t_without_array->fields.structure[i].type;
2784 
2785          /* When the interface block doesn't have an xfb_offset qualifier then
2786           * we apply the component size rules at the member level.
2787           */
2788          if (xfb_offset == -1)
2789             component_size = member_t->contains_double() ? 8 : 4;
2790 
2791          int xfb_offset = t_without_array->fields.structure[i].offset;
2792          validate_xfb_offset_qualifier(loc, state, xfb_offset, member_t,
2793                                        component_size);
2794       }
2795 
2796   /* Nested structs or interface block without offset may not have had an
2797    * offset applied yet so return.
2798    */
2799    if (xfb_offset == -1) {
2800      return true;
2801    }
2802 
2803    if (xfb_offset % component_size) {
2804       _mesa_glsl_error(loc, state,
2805                        "invalid qualifier xfb_offset=%d must be a multiple "
2806                        "of the first component size of the first qualified "
2807                        "variable or block member. Or double if an aggregate "
2808                        "that contains a double (%d).",
2809                        xfb_offset, component_size);
2810       return false;
2811    }
2812 
2813    return true;
2814 }
2815 
2816 static bool
validate_stream_qualifier(YYLTYPE * loc,struct _mesa_glsl_parse_state * state,unsigned stream)2817 validate_stream_qualifier(YYLTYPE *loc, struct _mesa_glsl_parse_state *state,
2818                           unsigned stream)
2819 {
2820    if (stream >= state->ctx->Const.MaxVertexStreams) {
2821       _mesa_glsl_error(loc, state,
2822                        "invalid stream specified %d is larger than "
2823                        "MAX_VERTEX_STREAMS - 1 (%d).",
2824                        stream, state->ctx->Const.MaxVertexStreams - 1);
2825       return false;
2826    }
2827 
2828    return true;
2829 }
2830 
2831 static void
apply_explicit_binding(struct _mesa_glsl_parse_state * state,YYLTYPE * loc,ir_variable * var,const glsl_type * type,const ast_type_qualifier * qual)2832 apply_explicit_binding(struct _mesa_glsl_parse_state *state,
2833                        YYLTYPE *loc,
2834                        ir_variable *var,
2835                        const glsl_type *type,
2836                        const ast_type_qualifier *qual)
2837 {
2838    if (!qual->flags.q.uniform && !qual->flags.q.buffer) {
2839       _mesa_glsl_error(loc, state,
2840                        "the \"binding\" qualifier only applies to uniforms and "
2841                        "shader storage buffer objects");
2842       return;
2843    }
2844 
2845    unsigned qual_binding;
2846    if (!process_qualifier_constant(state, loc, "binding", qual->binding,
2847                                    &qual_binding)) {
2848       return;
2849    }
2850 
2851    const struct gl_context *const ctx = state->ctx;
2852    unsigned elements = type->is_array() ? type->arrays_of_arrays_size() : 1;
2853    unsigned max_index = qual_binding + elements - 1;
2854    const glsl_type *base_type = type->without_array();
2855 
2856    if (base_type->is_interface()) {
2857       /* UBOs.  From page 60 of the GLSL 4.20 specification:
2858        * "If the binding point for any uniform block instance is less than zero,
2859        *  or greater than or equal to the implementation-dependent maximum
2860        *  number of uniform buffer bindings, a compilation error will occur.
2861        *  When the binding identifier is used with a uniform block instanced as
2862        *  an array of size N, all elements of the array from binding through
2863        *  binding + N – 1 must be within this range."
2864        *
2865        * The implementation-dependent maximum is GL_MAX_UNIFORM_BUFFER_BINDINGS.
2866        */
2867       if (qual->flags.q.uniform &&
2868          max_index >= ctx->Const.MaxUniformBufferBindings) {
2869          _mesa_glsl_error(loc, state, "layout(binding = %u) for %d UBOs exceeds "
2870                           "the maximum number of UBO binding points (%d)",
2871                           qual_binding, elements,
2872                           ctx->Const.MaxUniformBufferBindings);
2873          return;
2874       }
2875 
2876       /* SSBOs. From page 67 of the GLSL 4.30 specification:
2877        * "If the binding point for any uniform or shader storage block instance
2878        *  is less than zero, or greater than or equal to the
2879        *  implementation-dependent maximum number of uniform buffer bindings, a
2880        *  compile-time error will occur. When the binding identifier is used
2881        *  with a uniform or shader storage block instanced as an array of size
2882        *  N, all elements of the array from binding through binding + N – 1 must
2883        *  be within this range."
2884        */
2885       if (qual->flags.q.buffer &&
2886          max_index >= ctx->Const.MaxShaderStorageBufferBindings) {
2887          _mesa_glsl_error(loc, state, "layout(binding = %u) for %d SSBOs exceeds "
2888                           "the maximum number of SSBO binding points (%d)",
2889                           qual_binding, elements,
2890                           ctx->Const.MaxShaderStorageBufferBindings);
2891          return;
2892       }
2893    } else if (base_type->is_sampler()) {
2894       /* Samplers.  From page 63 of the GLSL 4.20 specification:
2895        * "If the binding is less than zero, or greater than or equal to the
2896        *  implementation-dependent maximum supported number of units, a
2897        *  compilation error will occur. When the binding identifier is used
2898        *  with an array of size N, all elements of the array from binding
2899        *  through binding + N - 1 must be within this range."
2900        */
2901       unsigned limit = ctx->Const.MaxCombinedTextureImageUnits;
2902 
2903       if (max_index >= limit) {
2904          _mesa_glsl_error(loc, state, "layout(binding = %d) for %d samplers "
2905                           "exceeds the maximum number of texture image units "
2906                           "(%u)", qual_binding, elements, limit);
2907 
2908          return;
2909       }
2910    } else if (base_type->contains_atomic()) {
2911       assert(ctx->Const.MaxAtomicBufferBindings <= MAX_COMBINED_ATOMIC_BUFFERS);
2912       if (qual_binding >= ctx->Const.MaxAtomicBufferBindings) {
2913          _mesa_glsl_error(loc, state, "layout(binding = %d) exceeds the "
2914                           "maximum number of atomic counter buffer bindings "
2915                           "(%u)", qual_binding,
2916                           ctx->Const.MaxAtomicBufferBindings);
2917 
2918          return;
2919       }
2920    } else if ((state->is_version(420, 310) ||
2921                state->ARB_shading_language_420pack_enable) &&
2922               base_type->is_image()) {
2923       assert(ctx->Const.MaxImageUnits <= MAX_IMAGE_UNITS);
2924       if (max_index >= ctx->Const.MaxImageUnits) {
2925          _mesa_glsl_error(loc, state, "Image binding %d exceeds the "
2926                           "maximum number of image units (%d)", max_index,
2927                           ctx->Const.MaxImageUnits);
2928          return;
2929       }
2930 
2931    } else {
2932       _mesa_glsl_error(loc, state,
2933                        "the \"binding\" qualifier only applies to uniform "
2934                        "blocks, storage blocks, opaque variables, or arrays "
2935                        "thereof");
2936       return;
2937    }
2938 
2939    var->data.explicit_binding = true;
2940    var->data.binding = qual_binding;
2941 
2942    return;
2943 }
2944 
2945 static void
validate_fragment_flat_interpolation_input(struct _mesa_glsl_parse_state * state,YYLTYPE * loc,const glsl_interp_mode interpolation,const struct glsl_type * var_type,ir_variable_mode mode)2946 validate_fragment_flat_interpolation_input(struct _mesa_glsl_parse_state *state,
2947                                            YYLTYPE *loc,
2948                                            const glsl_interp_mode interpolation,
2949                                            const struct glsl_type *var_type,
2950                                            ir_variable_mode mode)
2951 {
2952    if (state->stage != MESA_SHADER_FRAGMENT ||
2953        interpolation == INTERP_MODE_FLAT ||
2954        mode != ir_var_shader_in)
2955       return;
2956 
2957    /* Integer fragment inputs must be qualified with 'flat'.  In GLSL ES,
2958     * so must integer vertex outputs.
2959     *
2960     * From section 4.3.4 ("Inputs") of the GLSL 1.50 spec:
2961     *    "Fragment shader inputs that are signed or unsigned integers or
2962     *    integer vectors must be qualified with the interpolation qualifier
2963     *    flat."
2964     *
2965     * From section 4.3.4 ("Input Variables") of the GLSL 3.00 ES spec:
2966     *    "Fragment shader inputs that are, or contain, signed or unsigned
2967     *    integers or integer vectors must be qualified with the
2968     *    interpolation qualifier flat."
2969     *
2970     * From section 4.3.6 ("Output Variables") of the GLSL 3.00 ES spec:
2971     *    "Vertex shader outputs that are, or contain, signed or unsigned
2972     *    integers or integer vectors must be qualified with the
2973     *    interpolation qualifier flat."
2974     *
2975     * Note that prior to GLSL 1.50, this requirement applied to vertex
2976     * outputs rather than fragment inputs.  That creates problems in the
2977     * presence of geometry shaders, so we adopt the GLSL 1.50 rule for all
2978     * desktop GL shaders.  For GLSL ES shaders, we follow the spec and
2979     * apply the restriction to both vertex outputs and fragment inputs.
2980     *
2981     * Note also that the desktop GLSL specs are missing the text "or
2982     * contain"; this is presumably an oversight, since there is no
2983     * reasonable way to interpolate a fragment shader input that contains
2984     * an integer. See Khronos bug #15671.
2985     */
2986    if (state->is_version(130, 300)
2987        && var_type->contains_integer()) {
2988       _mesa_glsl_error(loc, state, "if a fragment input is (or contains) "
2989                        "an integer, then it must be qualified with 'flat'");
2990    }
2991 
2992    /* Double fragment inputs must be qualified with 'flat'.
2993     *
2994     * From the "Overview" of the ARB_gpu_shader_fp64 extension spec:
2995     *    "This extension does not support interpolation of double-precision
2996     *    values; doubles used as fragment shader inputs must be qualified as
2997     *    "flat"."
2998     *
2999     * From section 4.3.4 ("Inputs") of the GLSL 4.00 spec:
3000     *    "Fragment shader inputs that are signed or unsigned integers, integer
3001     *    vectors, or any double-precision floating-point type must be
3002     *    qualified with the interpolation qualifier flat."
3003     *
3004     * Note that the GLSL specs are missing the text "or contain"; this is
3005     * presumably an oversight. See Khronos bug #15671.
3006     *
3007     * The 'double' type does not exist in GLSL ES so far.
3008     */
3009    if (state->has_double()
3010        && var_type->contains_double()) {
3011       _mesa_glsl_error(loc, state, "if a fragment input is (or contains) "
3012                        "a double, then it must be qualified with 'flat'");
3013    }
3014 
3015    /* Bindless sampler/image fragment inputs must be qualified with 'flat'.
3016     *
3017     * From section 4.3.4 of the ARB_bindless_texture spec:
3018     *
3019     *    "(modify last paragraph, p. 35, allowing samplers and images as
3020     *     fragment shader inputs) ... Fragment inputs can only be signed and
3021     *     unsigned integers and integer vectors, floating point scalars,
3022     *     floating-point vectors, matrices, sampler and image types, or arrays
3023     *     or structures of these.  Fragment shader inputs that are signed or
3024     *     unsigned integers, integer vectors, or any double-precision floating-
3025     *     point type, or any sampler or image type must be qualified with the
3026     *     interpolation qualifier "flat"."
3027     */
3028    if (state->has_bindless()
3029        && (var_type->contains_sampler() || var_type->contains_image())) {
3030       _mesa_glsl_error(loc, state, "if a fragment input is (or contains) "
3031                        "a bindless sampler (or image), then it must be "
3032                        "qualified with 'flat'");
3033    }
3034 }
3035 
3036 static void
validate_interpolation_qualifier(struct _mesa_glsl_parse_state * state,YYLTYPE * loc,const glsl_interp_mode interpolation,const struct ast_type_qualifier * qual,const struct glsl_type * var_type,ir_variable_mode mode)3037 validate_interpolation_qualifier(struct _mesa_glsl_parse_state *state,
3038                                  YYLTYPE *loc,
3039                                  const glsl_interp_mode interpolation,
3040                                  const struct ast_type_qualifier *qual,
3041                                  const struct glsl_type *var_type,
3042                                  ir_variable_mode mode)
3043 {
3044    /* Interpolation qualifiers can only apply to shader inputs or outputs, but
3045     * not to vertex shader inputs nor fragment shader outputs.
3046     *
3047     * From section 4.3 ("Storage Qualifiers") of the GLSL 1.30 spec:
3048     *    "Outputs from a vertex shader (out) and inputs to a fragment
3049     *    shader (in) can be further qualified with one or more of these
3050     *    interpolation qualifiers"
3051     *    ...
3052     *    "These interpolation qualifiers may only precede the qualifiers in,
3053     *    centroid in, out, or centroid out in a declaration. They do not apply
3054     *    to the deprecated storage qualifiers varying or centroid
3055     *    varying. They also do not apply to inputs into a vertex shader or
3056     *    outputs from a fragment shader."
3057     *
3058     * From section 4.3 ("Storage Qualifiers") of the GLSL ES 3.00 spec:
3059     *    "Outputs from a shader (out) and inputs to a shader (in) can be
3060     *    further qualified with one of these interpolation qualifiers."
3061     *    ...
3062     *    "These interpolation qualifiers may only precede the qualifiers
3063     *    in, centroid in, out, or centroid out in a declaration. They do
3064     *    not apply to inputs into a vertex shader or outputs from a
3065     *    fragment shader."
3066     */
3067    if (state->is_version(130, 300)
3068        && interpolation != INTERP_MODE_NONE) {
3069       const char *i = interpolation_string(interpolation);
3070       if (mode != ir_var_shader_in && mode != ir_var_shader_out)
3071          _mesa_glsl_error(loc, state,
3072                           "interpolation qualifier `%s' can only be applied to "
3073                           "shader inputs or outputs.", i);
3074 
3075       switch (state->stage) {
3076       case MESA_SHADER_VERTEX:
3077          if (mode == ir_var_shader_in) {
3078             _mesa_glsl_error(loc, state,
3079                              "interpolation qualifier '%s' cannot be applied to "
3080                              "vertex shader inputs", i);
3081          }
3082          break;
3083       case MESA_SHADER_FRAGMENT:
3084          if (mode == ir_var_shader_out) {
3085             _mesa_glsl_error(loc, state,
3086                              "interpolation qualifier '%s' cannot be applied to "
3087                              "fragment shader outputs", i);
3088          }
3089          break;
3090       default:
3091          break;
3092       }
3093    }
3094 
3095    /* Interpolation qualifiers cannot be applied to 'centroid' and
3096     * 'centroid varying'.
3097     *
3098     * From section 4.3 ("Storage Qualifiers") of the GLSL 1.30 spec:
3099     *    "interpolation qualifiers may only precede the qualifiers in,
3100     *    centroid in, out, or centroid out in a declaration. They do not apply
3101     *    to the deprecated storage qualifiers varying or centroid varying."
3102     *
3103     * These deprecated storage qualifiers do not exist in GLSL ES 3.00.
3104     */
3105    if (state->is_version(130, 0)
3106        && interpolation != INTERP_MODE_NONE
3107        && qual->flags.q.varying) {
3108 
3109       const char *i = interpolation_string(interpolation);
3110       const char *s;
3111       if (qual->flags.q.centroid)
3112          s = "centroid varying";
3113       else
3114          s = "varying";
3115 
3116       _mesa_glsl_error(loc, state,
3117                        "qualifier '%s' cannot be applied to the "
3118                        "deprecated storage qualifier '%s'", i, s);
3119    }
3120 
3121    validate_fragment_flat_interpolation_input(state, loc, interpolation,
3122                                               var_type, mode);
3123 }
3124 
3125 static glsl_interp_mode
interpret_interpolation_qualifier(const struct ast_type_qualifier * qual,const struct glsl_type * var_type,ir_variable_mode mode,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)3126 interpret_interpolation_qualifier(const struct ast_type_qualifier *qual,
3127                                   const struct glsl_type *var_type,
3128                                   ir_variable_mode mode,
3129                                   struct _mesa_glsl_parse_state *state,
3130                                   YYLTYPE *loc)
3131 {
3132    glsl_interp_mode interpolation;
3133    if (qual->flags.q.flat)
3134       interpolation = INTERP_MODE_FLAT;
3135    else if (qual->flags.q.noperspective)
3136       interpolation = INTERP_MODE_NOPERSPECTIVE;
3137    else if (qual->flags.q.smooth)
3138       interpolation = INTERP_MODE_SMOOTH;
3139    else
3140       interpolation = INTERP_MODE_NONE;
3141 
3142    validate_interpolation_qualifier(state, loc,
3143                                     interpolation,
3144                                     qual, var_type, mode);
3145 
3146    return interpolation;
3147 }
3148 
3149 
3150 static void
apply_explicit_location(const struct ast_type_qualifier * qual,ir_variable * var,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)3151 apply_explicit_location(const struct ast_type_qualifier *qual,
3152                         ir_variable *var,
3153                         struct _mesa_glsl_parse_state *state,
3154                         YYLTYPE *loc)
3155 {
3156    bool fail = false;
3157 
3158    unsigned qual_location;
3159    if (!process_qualifier_constant(state, loc, "location", qual->location,
3160                                    &qual_location)) {
3161       return;
3162    }
3163 
3164    /* Checks for GL_ARB_explicit_uniform_location. */
3165    if (qual->flags.q.uniform) {
3166       if (!state->check_explicit_uniform_location_allowed(loc, var))
3167          return;
3168 
3169       const struct gl_context *const ctx = state->ctx;
3170       unsigned max_loc = qual_location + var->type->uniform_locations() - 1;
3171 
3172       if (max_loc >= ctx->Const.MaxUserAssignableUniformLocations) {
3173          _mesa_glsl_error(loc, state, "location(s) consumed by uniform %s "
3174                           ">= MAX_UNIFORM_LOCATIONS (%u)", var->name,
3175                           ctx->Const.MaxUserAssignableUniformLocations);
3176          return;
3177       }
3178 
3179       var->data.explicit_location = true;
3180       var->data.location = qual_location;
3181       return;
3182    }
3183 
3184    /* Between GL_ARB_explicit_attrib_location an
3185     * GL_ARB_separate_shader_objects, the inputs and outputs of any shader
3186     * stage can be assigned explicit locations.  The checking here associates
3187     * the correct extension with the correct stage's input / output:
3188     *
3189     *                     input            output
3190     *                     -----            ------
3191     * vertex              explicit_loc     sso
3192     * tess control        sso              sso
3193     * tess eval           sso              sso
3194     * geometry            sso              sso
3195     * fragment            sso              explicit_loc
3196     */
3197    switch (state->stage) {
3198    case MESA_SHADER_VERTEX:
3199       if (var->data.mode == ir_var_shader_in) {
3200          if (!state->check_explicit_attrib_location_allowed(loc, var))
3201             return;
3202 
3203          break;
3204       }
3205 
3206       if (var->data.mode == ir_var_shader_out) {
3207          if (!state->check_separate_shader_objects_allowed(loc, var))
3208             return;
3209 
3210          break;
3211       }
3212 
3213       fail = true;
3214       break;
3215 
3216    case MESA_SHADER_TESS_CTRL:
3217    case MESA_SHADER_TESS_EVAL:
3218    case MESA_SHADER_GEOMETRY:
3219       if (var->data.mode == ir_var_shader_in || var->data.mode == ir_var_shader_out) {
3220          if (!state->check_separate_shader_objects_allowed(loc, var))
3221             return;
3222 
3223          break;
3224       }
3225 
3226       fail = true;
3227       break;
3228 
3229    case MESA_SHADER_FRAGMENT:
3230       if (var->data.mode == ir_var_shader_in) {
3231          if (!state->check_separate_shader_objects_allowed(loc, var))
3232             return;
3233 
3234          break;
3235       }
3236 
3237       if (var->data.mode == ir_var_shader_out) {
3238          if (!state->check_explicit_attrib_location_allowed(loc, var))
3239             return;
3240 
3241          break;
3242       }
3243 
3244       fail = true;
3245       break;
3246 
3247    case MESA_SHADER_COMPUTE:
3248       _mesa_glsl_error(loc, state,
3249                        "compute shader variables cannot be given "
3250                        "explicit locations");
3251       return;
3252    default:
3253       fail = true;
3254       break;
3255    };
3256 
3257    if (fail) {
3258       _mesa_glsl_error(loc, state,
3259                        "%s cannot be given an explicit location in %s shader",
3260                        mode_string(var),
3261       _mesa_shader_stage_to_string(state->stage));
3262    } else {
3263       var->data.explicit_location = true;
3264 
3265       switch (state->stage) {
3266       case MESA_SHADER_VERTEX:
3267          var->data.location = (var->data.mode == ir_var_shader_in)
3268             ? (qual_location + VERT_ATTRIB_GENERIC0)
3269             : (qual_location + VARYING_SLOT_VAR0);
3270          break;
3271 
3272       case MESA_SHADER_TESS_CTRL:
3273       case MESA_SHADER_TESS_EVAL:
3274       case MESA_SHADER_GEOMETRY:
3275          if (var->data.patch)
3276             var->data.location = qual_location + VARYING_SLOT_PATCH0;
3277          else
3278             var->data.location = qual_location + VARYING_SLOT_VAR0;
3279          break;
3280 
3281       case MESA_SHADER_FRAGMENT:
3282          var->data.location = (var->data.mode == ir_var_shader_out)
3283             ? (qual_location + FRAG_RESULT_DATA0)
3284             : (qual_location + VARYING_SLOT_VAR0);
3285          break;
3286       default:
3287          assert(!"Unexpected shader type");
3288          break;
3289       }
3290 
3291       /* Check if index was set for the uniform instead of the function */
3292       if (qual->flags.q.explicit_index && qual->is_subroutine_decl()) {
3293          _mesa_glsl_error(loc, state, "an index qualifier can only be "
3294                           "used with subroutine functions");
3295          return;
3296       }
3297 
3298       unsigned qual_index;
3299       if (qual->flags.q.explicit_index &&
3300           process_qualifier_constant(state, loc, "index", qual->index,
3301                                      &qual_index)) {
3302          /* From the GLSL 4.30 specification, section 4.4.2 (Output
3303           * Layout Qualifiers):
3304           *
3305           * "It is also a compile-time error if a fragment shader
3306           *  sets a layout index to less than 0 or greater than 1."
3307           *
3308           * Older specifications don't mandate a behavior; we take
3309           * this as a clarification and always generate the error.
3310           */
3311          if (qual_index > 1) {
3312             _mesa_glsl_error(loc, state,
3313                              "explicit index may only be 0 or 1");
3314          } else {
3315             var->data.explicit_index = true;
3316             var->data.index = qual_index;
3317          }
3318       }
3319    }
3320 }
3321 
3322 static bool
validate_storage_for_sampler_image_types(ir_variable * var,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)3323 validate_storage_for_sampler_image_types(ir_variable *var,
3324                                          struct _mesa_glsl_parse_state *state,
3325                                          YYLTYPE *loc)
3326 {
3327    /* From section 4.1.7 of the GLSL 4.40 spec:
3328     *
3329     *    "[Opaque types] can only be declared as function
3330     *     parameters or uniform-qualified variables."
3331     *
3332     * From section 4.1.7 of the ARB_bindless_texture spec:
3333     *
3334     *    "Samplers may be declared as shader inputs and outputs, as uniform
3335     *     variables, as temporary variables, and as function parameters."
3336     *
3337     * From section 4.1.X of the ARB_bindless_texture spec:
3338     *
3339     *    "Images may be declared as shader inputs and outputs, as uniform
3340     *     variables, as temporary variables, and as function parameters."
3341     */
3342    if (state->has_bindless()) {
3343       if (var->data.mode != ir_var_auto &&
3344           var->data.mode != ir_var_uniform &&
3345           var->data.mode != ir_var_shader_in &&
3346           var->data.mode != ir_var_shader_out &&
3347           var->data.mode != ir_var_function_in &&
3348           var->data.mode != ir_var_function_out &&
3349           var->data.mode != ir_var_function_inout) {
3350          _mesa_glsl_error(loc, state, "bindless image/sampler variables may "
3351                          "only be declared as shader inputs and outputs, as "
3352                          "uniform variables, as temporary variables and as "
3353                          "function parameters");
3354          return false;
3355       }
3356    } else {
3357       if (var->data.mode != ir_var_uniform &&
3358           var->data.mode != ir_var_function_in) {
3359          _mesa_glsl_error(loc, state, "image/sampler variables may only be "
3360                           "declared as function parameters or "
3361                           "uniform-qualified global variables");
3362          return false;
3363       }
3364    }
3365    return true;
3366 }
3367 
3368 static bool
validate_memory_qualifier_for_type(struct _mesa_glsl_parse_state * state,YYLTYPE * loc,const struct ast_type_qualifier * qual,const glsl_type * type)3369 validate_memory_qualifier_for_type(struct _mesa_glsl_parse_state *state,
3370                                    YYLTYPE *loc,
3371                                    const struct ast_type_qualifier *qual,
3372                                    const glsl_type *type)
3373 {
3374    /* From Section 4.10 (Memory Qualifiers) of the GLSL 4.50 spec:
3375     *
3376     * "Memory qualifiers are only supported in the declarations of image
3377     *  variables, buffer variables, and shader storage blocks; it is an error
3378     *  to use such qualifiers in any other declarations.
3379     */
3380    if (!type->is_image() && !qual->flags.q.buffer) {
3381       if (qual->flags.q.read_only ||
3382           qual->flags.q.write_only ||
3383           qual->flags.q.coherent ||
3384           qual->flags.q._volatile ||
3385           qual->flags.q.restrict_flag) {
3386          _mesa_glsl_error(loc, state, "memory qualifiers may only be applied "
3387                           "in the declarations of image variables, buffer "
3388                           "variables, and shader storage blocks");
3389          return false;
3390       }
3391    }
3392    return true;
3393 }
3394 
3395 static bool
validate_image_format_qualifier_for_type(struct _mesa_glsl_parse_state * state,YYLTYPE * loc,const struct ast_type_qualifier * qual,const glsl_type * type)3396 validate_image_format_qualifier_for_type(struct _mesa_glsl_parse_state *state,
3397                                          YYLTYPE *loc,
3398                                          const struct ast_type_qualifier *qual,
3399                                          const glsl_type *type)
3400 {
3401    /* From section 4.4.6.2 (Format Layout Qualifiers) of the GLSL 4.50 spec:
3402     *
3403     * "Format layout qualifiers can be used on image variable declarations
3404     *  (those declared with a basic type  having “image ” in its keyword)."
3405     */
3406    if (!type->is_image() && qual->flags.q.explicit_image_format) {
3407       _mesa_glsl_error(loc, state, "format layout qualifiers may only be "
3408                        "applied to images");
3409       return false;
3410    }
3411    return true;
3412 }
3413 
3414 static void
apply_image_qualifier_to_variable(const struct ast_type_qualifier * qual,ir_variable * var,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)3415 apply_image_qualifier_to_variable(const struct ast_type_qualifier *qual,
3416                                   ir_variable *var,
3417                                   struct _mesa_glsl_parse_state *state,
3418                                   YYLTYPE *loc)
3419 {
3420    const glsl_type *base_type = var->type->without_array();
3421 
3422    if (!validate_image_format_qualifier_for_type(state, loc, qual, base_type) ||
3423        !validate_memory_qualifier_for_type(state, loc, qual, base_type))
3424       return;
3425 
3426    if (!base_type->is_image())
3427       return;
3428 
3429    if (!validate_storage_for_sampler_image_types(var, state, loc))
3430       return;
3431 
3432    var->data.memory_read_only |= qual->flags.q.read_only;
3433    var->data.memory_write_only |= qual->flags.q.write_only;
3434    var->data.memory_coherent |= qual->flags.q.coherent;
3435    var->data.memory_volatile |= qual->flags.q._volatile;
3436    var->data.memory_restrict |= qual->flags.q.restrict_flag;
3437 
3438    if (qual->flags.q.explicit_image_format) {
3439       if (var->data.mode == ir_var_function_in) {
3440          _mesa_glsl_error(loc, state, "format qualifiers cannot be used on "
3441                           "image function parameters");
3442       }
3443 
3444       if (qual->image_base_type != base_type->sampled_type) {
3445          _mesa_glsl_error(loc, state, "format qualifier doesn't match the base "
3446                           "data type of the image");
3447       }
3448 
3449       var->data.image_format = qual->image_format;
3450    } else {
3451       if (var->data.mode == ir_var_uniform) {
3452          if (state->es_shader) {
3453             _mesa_glsl_error(loc, state, "all image uniforms must have a "
3454                              "format layout qualifier");
3455          } else if (!qual->flags.q.write_only) {
3456             _mesa_glsl_error(loc, state, "image uniforms not qualified with "
3457                              "`writeonly' must have a format layout qualifier");
3458          }
3459       }
3460       var->data.image_format = GL_NONE;
3461    }
3462 
3463    /* From page 70 of the GLSL ES 3.1 specification:
3464     *
3465     * "Except for image variables qualified with the format qualifiers r32f,
3466     *  r32i, and r32ui, image variables must specify either memory qualifier
3467     *  readonly or the memory qualifier writeonly."
3468     */
3469    if (state->es_shader &&
3470        var->data.image_format != GL_R32F &&
3471        var->data.image_format != GL_R32I &&
3472        var->data.image_format != GL_R32UI &&
3473        !var->data.memory_read_only &&
3474        !var->data.memory_write_only) {
3475       _mesa_glsl_error(loc, state, "image variables of format other than r32f, "
3476                        "r32i or r32ui must be qualified `readonly' or "
3477                        "`writeonly'");
3478    }
3479 }
3480 
3481 static inline const char*
get_layout_qualifier_string(bool origin_upper_left,bool pixel_center_integer)3482 get_layout_qualifier_string(bool origin_upper_left, bool pixel_center_integer)
3483 {
3484    if (origin_upper_left && pixel_center_integer)
3485       return "origin_upper_left, pixel_center_integer";
3486    else if (origin_upper_left)
3487       return "origin_upper_left";
3488    else if (pixel_center_integer)
3489       return "pixel_center_integer";
3490    else
3491       return " ";
3492 }
3493 
3494 static inline bool
is_conflicting_fragcoord_redeclaration(struct _mesa_glsl_parse_state * state,const struct ast_type_qualifier * qual)3495 is_conflicting_fragcoord_redeclaration(struct _mesa_glsl_parse_state *state,
3496                                        const struct ast_type_qualifier *qual)
3497 {
3498    /* If gl_FragCoord was previously declared, and the qualifiers were
3499     * different in any way, return true.
3500     */
3501    if (state->fs_redeclares_gl_fragcoord) {
3502       return (state->fs_pixel_center_integer != qual->flags.q.pixel_center_integer
3503          || state->fs_origin_upper_left != qual->flags.q.origin_upper_left);
3504    }
3505 
3506    return false;
3507 }
3508 
3509 static inline void
validate_array_dimensions(const glsl_type * t,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)3510 validate_array_dimensions(const glsl_type *t,
3511                           struct _mesa_glsl_parse_state *state,
3512                           YYLTYPE *loc) {
3513    if (t->is_array()) {
3514       t = t->fields.array;
3515       while (t->is_array()) {
3516          if (t->is_unsized_array()) {
3517             _mesa_glsl_error(loc, state,
3518                              "only the outermost array dimension can "
3519                              "be unsized",
3520                              t->name);
3521             break;
3522          }
3523          t = t->fields.array;
3524       }
3525    }
3526 }
3527 
3528 static void
apply_bindless_qualifier_to_variable(const struct ast_type_qualifier * qual,ir_variable * var,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)3529 apply_bindless_qualifier_to_variable(const struct ast_type_qualifier *qual,
3530                                      ir_variable *var,
3531                                      struct _mesa_glsl_parse_state *state,
3532                                      YYLTYPE *loc)
3533 {
3534    bool has_local_qualifiers = qual->flags.q.bindless_sampler ||
3535                                qual->flags.q.bindless_image ||
3536                                qual->flags.q.bound_sampler ||
3537                                qual->flags.q.bound_image;
3538 
3539    /* The ARB_bindless_texture spec says:
3540     *
3541     * "Modify Section 4.4.6 Opaque-Uniform Layout Qualifiers of the GLSL 4.30
3542     *  spec"
3543     *
3544     * "If these layout qualifiers are applied to other types of default block
3545     *  uniforms, or variables with non-uniform storage, a compile-time error
3546     *  will be generated."
3547     */
3548    if (has_local_qualifiers && !qual->flags.q.uniform) {
3549       _mesa_glsl_error(loc, state, "ARB_bindless_texture layout qualifiers "
3550                        "can only be applied to default block uniforms or "
3551                        "variables with uniform storage");
3552       return;
3553    }
3554 
3555    /* The ARB_bindless_texture spec doesn't state anything in this situation,
3556     * but it makes sense to only allow bindless_sampler/bound_sampler for
3557     * sampler types, and respectively bindless_image/bound_image for image
3558     * types.
3559     */
3560    if ((qual->flags.q.bindless_sampler || qual->flags.q.bound_sampler) &&
3561        !var->type->contains_sampler()) {
3562       _mesa_glsl_error(loc, state, "bindless_sampler or bound_sampler can only "
3563                        "be applied to sampler types");
3564       return;
3565    }
3566 
3567    if ((qual->flags.q.bindless_image || qual->flags.q.bound_image) &&
3568        !var->type->contains_image()) {
3569       _mesa_glsl_error(loc, state, "bindless_image or bound_image can only be "
3570                        "applied to image types");
3571       return;
3572    }
3573 
3574    /* The bindless_sampler/bindless_image (and respectively
3575     * bound_sampler/bound_image) layout qualifiers can be set at global and at
3576     * local scope.
3577     */
3578    if (var->type->contains_sampler() || var->type->contains_image()) {
3579       var->data.bindless = qual->flags.q.bindless_sampler ||
3580                            qual->flags.q.bindless_image ||
3581                            state->bindless_sampler_specified ||
3582                            state->bindless_image_specified;
3583 
3584       var->data.bound = qual->flags.q.bound_sampler ||
3585                         qual->flags.q.bound_image ||
3586                         state->bound_sampler_specified ||
3587                         state->bound_image_specified;
3588    }
3589 }
3590 
3591 static void
apply_layout_qualifier_to_variable(const struct ast_type_qualifier * qual,ir_variable * var,struct _mesa_glsl_parse_state * state,YYLTYPE * loc)3592 apply_layout_qualifier_to_variable(const struct ast_type_qualifier *qual,
3593                                    ir_variable *var,
3594                                    struct _mesa_glsl_parse_state *state,
3595                                    YYLTYPE *loc)
3596 {
3597    if (var->name != NULL && strcmp(var->name, "gl_FragCoord") == 0) {
3598 
3599       /* Section 4.3.8.1, page 39 of GLSL 1.50 spec says:
3600        *
3601        *    "Within any shader, the first redeclarations of gl_FragCoord
3602        *     must appear before any use of gl_FragCoord."
3603        *
3604        * Generate a compiler error if above condition is not met by the
3605        * fragment shader.
3606        */
3607       ir_variable *earlier = state->symbols->get_variable("gl_FragCoord");
3608       if (earlier != NULL &&
3609           earlier->data.used &&
3610           !state->fs_redeclares_gl_fragcoord) {
3611          _mesa_glsl_error(loc, state,
3612                           "gl_FragCoord used before its first redeclaration "
3613                           "in fragment shader");
3614       }
3615 
3616       /* Make sure all gl_FragCoord redeclarations specify the same layout
3617        * qualifiers.
3618        */
3619       if (is_conflicting_fragcoord_redeclaration(state, qual)) {
3620          const char *const qual_string =
3621             get_layout_qualifier_string(qual->flags.q.origin_upper_left,
3622                                         qual->flags.q.pixel_center_integer);
3623 
3624          const char *const state_string =
3625             get_layout_qualifier_string(state->fs_origin_upper_left,
3626                                         state->fs_pixel_center_integer);
3627 
3628          _mesa_glsl_error(loc, state,
3629                           "gl_FragCoord redeclared with different layout "
3630                           "qualifiers (%s) and (%s) ",
3631                           state_string,
3632                           qual_string);
3633       }
3634       state->fs_origin_upper_left = qual->flags.q.origin_upper_left;
3635       state->fs_pixel_center_integer = qual->flags.q.pixel_center_integer;
3636       state->fs_redeclares_gl_fragcoord_with_no_layout_qualifiers =
3637          !qual->flags.q.origin_upper_left && !qual->flags.q.pixel_center_integer;
3638       state->fs_redeclares_gl_fragcoord =
3639          state->fs_origin_upper_left ||
3640          state->fs_pixel_center_integer ||
3641          state->fs_redeclares_gl_fragcoord_with_no_layout_qualifiers;
3642    }
3643 
3644    var->data.pixel_center_integer = qual->flags.q.pixel_center_integer;
3645    var->data.origin_upper_left = qual->flags.q.origin_upper_left;
3646    if ((qual->flags.q.origin_upper_left || qual->flags.q.pixel_center_integer)
3647        && (strcmp(var->name, "gl_FragCoord") != 0)) {
3648       const char *const qual_string = (qual->flags.q.origin_upper_left)
3649          ? "origin_upper_left" : "pixel_center_integer";
3650 
3651       _mesa_glsl_error(loc, state,
3652                        "layout qualifier `%s' can only be applied to "
3653                        "fragment shader input `gl_FragCoord'",
3654                        qual_string);
3655    }
3656 
3657    if (qual->flags.q.explicit_location) {
3658       apply_explicit_location(qual, var, state, loc);
3659 
3660       if (qual->flags.q.explicit_component) {
3661          unsigned qual_component;
3662          if (process_qualifier_constant(state, loc, "component",
3663                                         qual->component, &qual_component)) {
3664             const glsl_type *type = var->type->without_array();
3665             unsigned components = type->component_slots();
3666 
3667             if (type->is_matrix() || type->is_record()) {
3668                _mesa_glsl_error(loc, state, "component layout qualifier "
3669                                 "cannot be applied to a matrix, a structure, "
3670                                 "a block, or an array containing any of "
3671                                 "these.");
3672             } else if (qual_component != 0 &&
3673                 (qual_component + components - 1) > 3) {
3674                _mesa_glsl_error(loc, state, "component overflow (%u > 3)",
3675                                 (qual_component + components - 1));
3676             } else if (qual_component == 1 && type->is_64bit()) {
3677                /* We don't bother checking for 3 as it should be caught by the
3678                 * overflow check above.
3679                 */
3680                _mesa_glsl_error(loc, state, "doubles cannot begin at "
3681                                 "component 1 or 3");
3682             } else {
3683                var->data.explicit_component = true;
3684                var->data.location_frac = qual_component;
3685             }
3686          }
3687       }
3688    } else if (qual->flags.q.explicit_index) {
3689       if (!qual->subroutine_list)
3690          _mesa_glsl_error(loc, state,
3691                           "explicit index requires explicit location");
3692    } else if (qual->flags.q.explicit_component) {
3693       _mesa_glsl_error(loc, state,
3694                        "explicit component requires explicit location");
3695    }
3696 
3697    if (qual->flags.q.explicit_binding) {
3698       apply_explicit_binding(state, loc, var, var->type, qual);
3699    }
3700 
3701    if (state->stage == MESA_SHADER_GEOMETRY &&
3702        qual->flags.q.out && qual->flags.q.stream) {
3703       unsigned qual_stream;
3704       if (process_qualifier_constant(state, loc, "stream", qual->stream,
3705                                      &qual_stream) &&
3706           validate_stream_qualifier(loc, state, qual_stream)) {
3707          var->data.stream = qual_stream;
3708       }
3709    }
3710 
3711    if (qual->flags.q.out && qual->flags.q.xfb_buffer) {
3712       unsigned qual_xfb_buffer;
3713       if (process_qualifier_constant(state, loc, "xfb_buffer",
3714                                      qual->xfb_buffer, &qual_xfb_buffer) &&
3715           validate_xfb_buffer_qualifier(loc, state, qual_xfb_buffer)) {
3716          var->data.xfb_buffer = qual_xfb_buffer;
3717          if (qual->flags.q.explicit_xfb_buffer)
3718             var->data.explicit_xfb_buffer = true;
3719       }
3720    }
3721 
3722    if (qual->flags.q.explicit_xfb_offset) {
3723       unsigned qual_xfb_offset;
3724       unsigned component_size = var->type->contains_double() ? 8 : 4;
3725 
3726       if (process_qualifier_constant(state, loc, "xfb_offset",
3727                                      qual->offset, &qual_xfb_offset) &&
3728           validate_xfb_offset_qualifier(loc, state, (int) qual_xfb_offset,
3729                                         var->type, component_size)) {
3730          var->data.offset = qual_xfb_offset;
3731          var->data.explicit_xfb_offset = true;
3732       }
3733    }
3734 
3735    if (qual->flags.q.explicit_xfb_stride) {
3736       unsigned qual_xfb_stride;
3737       if (process_qualifier_constant(state, loc, "xfb_stride",
3738                                      qual->xfb_stride, &qual_xfb_stride)) {
3739          var->data.xfb_stride = qual_xfb_stride;
3740          var->data.explicit_xfb_stride = true;
3741       }
3742    }
3743 
3744    if (var->type->contains_atomic()) {
3745       if (var->data.mode == ir_var_uniform) {
3746          if (var->data.explicit_binding) {
3747             unsigned *offset =
3748                &state->atomic_counter_offsets[var->data.binding];
3749 
3750             if (*offset % ATOMIC_COUNTER_SIZE)
3751                _mesa_glsl_error(loc, state,
3752                                 "misaligned atomic counter offset");
3753 
3754             var->data.offset = *offset;
3755             *offset += var->type->atomic_size();
3756 
3757          } else {
3758             _mesa_glsl_error(loc, state,
3759                              "atomic counters require explicit binding point");
3760          }
3761       } else if (var->data.mode != ir_var_function_in) {
3762          _mesa_glsl_error(loc, state, "atomic counters may only be declared as "
3763                           "function parameters or uniform-qualified "
3764                           "global variables");
3765       }
3766    }
3767 
3768    if (var->type->contains_sampler() &&
3769        !validate_storage_for_sampler_image_types(var, state, loc))
3770       return;
3771 
3772    /* Is the 'layout' keyword used with parameters that allow relaxed checking.
3773     * Many implementations of GL_ARB_fragment_coord_conventions_enable and some
3774     * implementations (only Mesa?) GL_ARB_explicit_attrib_location_enable
3775     * allowed the layout qualifier to be used with 'varying' and 'attribute'.
3776     * These extensions and all following extensions that add the 'layout'
3777     * keyword have been modified to require the use of 'in' or 'out'.
3778     *
3779     * The following extension do not allow the deprecated keywords:
3780     *
3781     *    GL_AMD_conservative_depth
3782     *    GL_ARB_conservative_depth
3783     *    GL_ARB_gpu_shader5
3784     *    GL_ARB_separate_shader_objects
3785     *    GL_ARB_tessellation_shader
3786     *    GL_ARB_transform_feedback3
3787     *    GL_ARB_uniform_buffer_object
3788     *
3789     * It is unknown whether GL_EXT_shader_image_load_store or GL_NV_gpu_shader5
3790     * allow layout with the deprecated keywords.
3791     */
3792    const bool relaxed_layout_qualifier_checking =
3793       state->ARB_fragment_coord_conventions_enable;
3794 
3795    const bool uses_deprecated_qualifier = qual->flags.q.attribute
3796       || qual->flags.q.varying;
3797    if (qual->has_layout() && uses_deprecated_qualifier) {
3798       if (relaxed_layout_qualifier_checking) {
3799          _mesa_glsl_warning(loc, state,
3800                             "`layout' qualifier may not be used with "
3801                             "`attribute' or `varying'");
3802       } else {
3803          _mesa_glsl_error(loc, state,
3804                           "`layout' qualifier may not be used with "
3805                           "`attribute' or `varying'");
3806       }
3807    }
3808 
3809    /* Layout qualifiers for gl_FragDepth, which are enabled by extension
3810     * AMD_conservative_depth.
3811     */
3812    if (qual->flags.q.depth_type
3813        && !state->is_version(420, 0)
3814        && !state->AMD_conservative_depth_enable
3815        && !state->ARB_conservative_depth_enable) {
3816        _mesa_glsl_error(loc, state,
3817                         "extension GL_AMD_conservative_depth or "
3818                         "GL_ARB_conservative_depth must be enabled "
3819                         "to use depth layout qualifiers");
3820    } else if (qual->flags.q.depth_type
3821               && strcmp(var->name, "gl_FragDepth") != 0) {
3822        _mesa_glsl_error(loc, state,
3823                         "depth layout qualifiers can be applied only to "
3824                         "gl_FragDepth");
3825    }
3826 
3827    switch (qual->depth_type) {
3828    case ast_depth_any:
3829       var->data.depth_layout = ir_depth_layout_any;
3830       break;
3831    case ast_depth_greater:
3832       var->data.depth_layout = ir_depth_layout_greater;
3833       break;
3834    case ast_depth_less:
3835       var->data.depth_layout = ir_depth_layout_less;
3836       break;
3837    case ast_depth_unchanged:
3838       var->data.depth_layout = ir_depth_layout_unchanged;
3839       break;
3840    default:
3841       var->data.depth_layout = ir_depth_layout_none;
3842       break;
3843    }
3844 
3845    if (qual->flags.q.std140 ||
3846        qual->flags.q.std430 ||
3847        qual->flags.q.packed ||
3848        qual->flags.q.shared) {
3849       _mesa_glsl_error(loc, state,
3850                        "uniform and shader storage block layout qualifiers "
3851                        "std140, std430, packed, and shared can only be "
3852                        "applied to uniform or shader storage blocks, not "
3853                        "members");
3854    }
3855 
3856    if (qual->flags.q.row_major || qual->flags.q.column_major) {
3857       validate_matrix_layout_for_type(state, loc, var->type, var);
3858    }
3859 
3860    /* From section 4.4.1.3 of the GLSL 4.50 specification (Fragment Shader
3861     * Inputs):
3862     *
3863     *  "Fragment shaders also allow the following layout qualifier on in only
3864     *   (not with variable declarations)
3865     *     layout-qualifier-id
3866     *        early_fragment_tests
3867     *   [...]"
3868     */
3869    if (qual->flags.q.early_fragment_tests) {
3870       _mesa_glsl_error(loc, state, "early_fragment_tests layout qualifier only "
3871                        "valid in fragment shader input layout declaration.");
3872    }
3873 
3874    if (qual->flags.q.inner_coverage) {
3875       _mesa_glsl_error(loc, state, "inner_coverage layout qualifier only "
3876                        "valid in fragment shader input layout declaration.");
3877    }
3878 
3879    if (qual->flags.q.post_depth_coverage) {
3880       _mesa_glsl_error(loc, state, "post_depth_coverage layout qualifier only "
3881                        "valid in fragment shader input layout declaration.");
3882    }
3883 
3884    if (state->has_bindless())
3885       apply_bindless_qualifier_to_variable(qual, var, state, loc);
3886 }
3887 
3888 static void
apply_type_qualifier_to_variable(const struct ast_type_qualifier * qual,ir_variable * var,struct _mesa_glsl_parse_state * state,YYLTYPE * loc,bool is_parameter)3889 apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual,
3890                                  ir_variable *var,
3891                                  struct _mesa_glsl_parse_state *state,
3892                                  YYLTYPE *loc,
3893                                  bool is_parameter)
3894 {
3895    STATIC_ASSERT(sizeof(qual->flags.q) <= sizeof(qual->flags.i));
3896 
3897    if (qual->flags.q.invariant) {
3898       if (var->data.used) {
3899          _mesa_glsl_error(loc, state,
3900                           "variable `%s' may not be redeclared "
3901                           "`invariant' after being used",
3902                           var->name);
3903       } else {
3904          var->data.invariant = 1;
3905       }
3906    }
3907 
3908    if (qual->flags.q.precise) {
3909       if (var->data.used) {
3910          _mesa_glsl_error(loc, state,
3911                           "variable `%s' may not be redeclared "
3912                           "`precise' after being used",
3913                           var->name);
3914       } else {
3915          var->data.precise = 1;
3916       }
3917    }
3918 
3919    if (qual->is_subroutine_decl() && !qual->flags.q.uniform) {
3920       _mesa_glsl_error(loc, state,
3921                        "`subroutine' may only be applied to uniforms, "
3922                        "subroutine type declarations, or function definitions");
3923    }
3924 
3925    if (qual->flags.q.constant || qual->flags.q.attribute
3926        || qual->flags.q.uniform
3927        || (qual->flags.q.varying && (state->stage == MESA_SHADER_FRAGMENT)))
3928       var->data.read_only = 1;
3929 
3930    if (qual->flags.q.centroid)
3931       var->data.centroid = 1;
3932 
3933    if (qual->flags.q.sample)
3934       var->data.sample = 1;
3935 
3936    /* Precision qualifiers do not hold any meaning in Desktop GLSL */
3937    if (state->es_shader) {
3938       var->data.precision =
3939          select_gles_precision(qual->precision, var->type, state, loc);
3940    }
3941 
3942    if (qual->flags.q.patch)
3943       var->data.patch = 1;
3944 
3945    if (qual->flags.q.attribute && state->stage != MESA_SHADER_VERTEX) {
3946       var->type = glsl_type::error_type;
3947       _mesa_glsl_error(loc, state,
3948                        "`attribute' variables may not be declared in the "
3949                        "%s shader",
3950                        _mesa_shader_stage_to_string(state->stage));
3951    }
3952 
3953    /* Disallow layout qualifiers which may only appear on layout declarations. */
3954    if (qual->flags.q.prim_type) {
3955       _mesa_glsl_error(loc, state,
3956                        "Primitive type may only be specified on GS input or output "
3957                        "layout declaration, not on variables.");
3958    }
3959 
3960    /* Section 6.1.1 (Function Calling Conventions) of the GLSL 1.10 spec says:
3961     *
3962     *     "However, the const qualifier cannot be used with out or inout."
3963     *
3964     * The same section of the GLSL 4.40 spec further clarifies this saying:
3965     *
3966     *     "The const qualifier cannot be used with out or inout, or a
3967     *     compile-time error results."
3968     */
3969    if (is_parameter && qual->flags.q.constant && qual->flags.q.out) {
3970       _mesa_glsl_error(loc, state,
3971                        "`const' may not be applied to `out' or `inout' "
3972                        "function parameters");
3973    }
3974 
3975    /* If there is no qualifier that changes the mode of the variable, leave
3976     * the setting alone.
3977     */
3978    assert(var->data.mode != ir_var_temporary);
3979    if (qual->flags.q.in && qual->flags.q.out)
3980       var->data.mode = is_parameter ? ir_var_function_inout : ir_var_shader_out;
3981    else if (qual->flags.q.in)
3982       var->data.mode = is_parameter ? ir_var_function_in : ir_var_shader_in;
3983    else if (qual->flags.q.attribute
3984             || (qual->flags.q.varying && (state->stage == MESA_SHADER_FRAGMENT)))
3985       var->data.mode = ir_var_shader_in;
3986    else if (qual->flags.q.out)
3987       var->data.mode = is_parameter ? ir_var_function_out : ir_var_shader_out;
3988    else if (qual->flags.q.varying && (state->stage == MESA_SHADER_VERTEX))
3989       var->data.mode = ir_var_shader_out;
3990    else if (qual->flags.q.uniform)
3991       var->data.mode = ir_var_uniform;
3992    else if (qual->flags.q.buffer)
3993       var->data.mode = ir_var_shader_storage;
3994    else if (qual->flags.q.shared_storage)
3995       var->data.mode = ir_var_shader_shared;
3996 
3997    var->data.fb_fetch_output = state->stage == MESA_SHADER_FRAGMENT &&
3998                                qual->flags.q.in && qual->flags.q.out;
3999 
4000    if (!is_parameter && is_varying_var(var, state->stage)) {
4001       /* User-defined ins/outs are not permitted in compute shaders. */
4002       if (state->stage == MESA_SHADER_COMPUTE) {
4003          _mesa_glsl_error(loc, state,
4004                           "user-defined input and output variables are not "
4005                           "permitted in compute shaders");
4006       }
4007 
4008       /* This variable is being used to link data between shader stages (in
4009        * pre-glsl-1.30 parlance, it's a "varying").  Check that it has a type
4010        * that is allowed for such purposes.
4011        *
4012        * From page 25 (page 31 of the PDF) of the GLSL 1.10 spec:
4013        *
4014        *     "The varying qualifier can be used only with the data types
4015        *     float, vec2, vec3, vec4, mat2, mat3, and mat4, or arrays of
4016        *     these."
4017        *
4018        * This was relaxed in GLSL version 1.30 and GLSL ES version 3.00.  From
4019        * page 31 (page 37 of the PDF) of the GLSL 1.30 spec:
4020        *
4021        *     "Fragment inputs can only be signed and unsigned integers and
4022        *     integer vectors, float, floating-point vectors, matrices, or
4023        *     arrays of these. Structures cannot be input.
4024        *
4025        * Similar text exists in the section on vertex shader outputs.
4026        *
4027        * Similar text exists in the GLSL ES 3.00 spec, except that the GLSL ES
4028        * 3.00 spec allows structs as well.  Varying structs are also allowed
4029        * in GLSL 1.50.
4030        *
4031        * From section 4.3.4 of the ARB_bindless_texture spec:
4032        *
4033        *     "(modify third paragraph of the section to allow sampler and image
4034        *     types) ...  Vertex shader inputs can only be float,
4035        *     single-precision floating-point scalars, single-precision
4036        *     floating-point vectors, matrices, signed and unsigned integers
4037        *     and integer vectors, sampler and image types."
4038        *
4039        * From section 4.3.6 of the ARB_bindless_texture spec:
4040        *
4041        *     "Output variables can only be floating-point scalars,
4042        *     floating-point vectors, matrices, signed or unsigned integers or
4043        *     integer vectors, sampler or image types, or arrays or structures
4044        *     of any these."
4045        */
4046       switch (var->type->without_array()->base_type) {
4047       case GLSL_TYPE_FLOAT:
4048          /* Ok in all GLSL versions */
4049          break;
4050       case GLSL_TYPE_UINT:
4051       case GLSL_TYPE_INT:
4052          if (state->is_version(130, 300))
4053             break;
4054          _mesa_glsl_error(loc, state,
4055                           "varying variables must be of base type float in %s",
4056                           state->get_version_string());
4057          break;
4058       case GLSL_TYPE_STRUCT:
4059          if (state->is_version(150, 300))
4060             break;
4061          _mesa_glsl_error(loc, state,
4062                           "varying variables may not be of type struct");
4063          break;
4064       case GLSL_TYPE_DOUBLE:
4065       case GLSL_TYPE_UINT64:
4066       case GLSL_TYPE_INT64:
4067          break;
4068       case GLSL_TYPE_SAMPLER:
4069       case GLSL_TYPE_IMAGE:
4070          if (state->has_bindless())
4071             break;
4072          /* fallthrough */
4073       default:
4074          _mesa_glsl_error(loc, state, "illegal type for a varying variable");
4075          break;
4076       }
4077    }
4078 
4079    if (state->all_invariant && var->data.mode == ir_var_shader_out)
4080       var->data.invariant = true;
4081 
4082    var->data.interpolation =
4083       interpret_interpolation_qualifier(qual, var->type,
4084                                         (ir_variable_mode) var->data.mode,
4085                                         state, loc);
4086 
4087    /* Does the declaration use the deprecated 'attribute' or 'varying'
4088     * keywords?
4089     */
4090    const bool uses_deprecated_qualifier = qual->flags.q.attribute
4091       || qual->flags.q.varying;
4092 
4093 
4094    /* Validate auxiliary storage qualifiers */
4095 
4096    /* From section 4.3.4 of the GLSL 1.30 spec:
4097     *    "It is an error to use centroid in in a vertex shader."
4098     *
4099     * From section 4.3.4 of the GLSL ES 3.00 spec:
4100     *    "It is an error to use centroid in or interpolation qualifiers in
4101     *    a vertex shader input."
4102     */
4103 
4104    /* Section 4.3.6 of the GLSL 1.30 specification states:
4105     * "It is an error to use centroid out in a fragment shader."
4106     *
4107     * The GL_ARB_shading_language_420pack extension specification states:
4108     * "It is an error to use auxiliary storage qualifiers or interpolation
4109     *  qualifiers on an output in a fragment shader."
4110     */
4111    if (qual->flags.q.sample && (!is_varying_var(var, state->stage) || uses_deprecated_qualifier)) {
4112       _mesa_glsl_error(loc, state,
4113                        "sample qualifier may only be used on `in` or `out` "
4114                        "variables between shader stages");
4115    }
4116    if (qual->flags.q.centroid && !is_varying_var(var, state->stage)) {
4117       _mesa_glsl_error(loc, state,
4118                        "centroid qualifier may only be used with `in', "
4119                        "`out' or `varying' variables between shader stages");
4120    }
4121 
4122    if (qual->flags.q.shared_storage && state->stage != MESA_SHADER_COMPUTE) {
4123       _mesa_glsl_error(loc, state,
4124                        "the shared storage qualifiers can only be used with "
4125                        "compute shaders");
4126    }
4127 
4128    apply_image_qualifier_to_variable(qual, var, state, loc);
4129 }
4130 
4131 /**
4132  * Get the variable that is being redeclared by this declaration or if it
4133  * does not exist, the current declared variable.
4134  *
4135  * Semantic checks to verify the validity of the redeclaration are also
4136  * performed.  If semantic checks fail, compilation error will be emitted via
4137  * \c _mesa_glsl_error, but a non-\c NULL pointer will still be returned.
4138  *
4139  * \returns
4140  * A pointer to an existing variable in the current scope if the declaration
4141  * is a redeclaration, current variable otherwise. \c is_declared boolean
4142  * will return \c true if the declaration is a redeclaration, \c false
4143  * otherwise.
4144  */
4145 static ir_variable *
get_variable_being_redeclared(ir_variable ** var_ptr,YYLTYPE loc,struct _mesa_glsl_parse_state * state,bool allow_all_redeclarations,bool * is_redeclaration)4146 get_variable_being_redeclared(ir_variable **var_ptr, YYLTYPE loc,
4147                               struct _mesa_glsl_parse_state *state,
4148                               bool allow_all_redeclarations,
4149                               bool *is_redeclaration)
4150 {
4151    ir_variable *var = *var_ptr;
4152 
4153    /* Check if this declaration is actually a re-declaration, either to
4154     * resize an array or add qualifiers to an existing variable.
4155     *
4156     * This is allowed for variables in the current scope, or when at
4157     * global scope (for built-ins in the implicit outer scope).
4158     */
4159    ir_variable *earlier = state->symbols->get_variable(var->name);
4160    if (earlier == NULL ||
4161        (state->current_function != NULL &&
4162        !state->symbols->name_declared_this_scope(var->name))) {
4163       *is_redeclaration = false;
4164       return var;
4165    }
4166 
4167    *is_redeclaration = true;
4168 
4169    /* From page 24 (page 30 of the PDF) of the GLSL 1.50 spec,
4170     *
4171     * "It is legal to declare an array without a size and then
4172     *  later re-declare the same name as an array of the same
4173     *  type and specify a size."
4174     */
4175    if (earlier->type->is_unsized_array() && var->type->is_array()
4176        && (var->type->fields.array == earlier->type->fields.array)) {
4177       /* FINISHME: This doesn't match the qualifiers on the two
4178        * FINISHME: declarations.  It's not 100% clear whether this is
4179        * FINISHME: required or not.
4180        */
4181 
4182       const int size = var->type->array_size();
4183       check_builtin_array_max_size(var->name, size, loc, state);
4184       if ((size > 0) && (size <= earlier->data.max_array_access)) {
4185          _mesa_glsl_error(& loc, state, "array size must be > %u due to "
4186                           "previous access",
4187                           earlier->data.max_array_access);
4188       }
4189 
4190       earlier->type = var->type;
4191       delete var;
4192       var = NULL;
4193       *var_ptr = NULL;
4194    } else if ((state->ARB_fragment_coord_conventions_enable ||
4195               state->is_version(150, 0))
4196               && strcmp(var->name, "gl_FragCoord") == 0
4197               && earlier->type == var->type
4198               && var->data.mode == ir_var_shader_in) {
4199       /* Allow redeclaration of gl_FragCoord for ARB_fcc layout
4200        * qualifiers.
4201        */
4202       earlier->data.origin_upper_left = var->data.origin_upper_left;
4203       earlier->data.pixel_center_integer = var->data.pixel_center_integer;
4204 
4205       /* According to section 4.3.7 of the GLSL 1.30 spec,
4206        * the following built-in varaibles can be redeclared with an
4207        * interpolation qualifier:
4208        *    * gl_FrontColor
4209        *    * gl_BackColor
4210        *    * gl_FrontSecondaryColor
4211        *    * gl_BackSecondaryColor
4212        *    * gl_Color
4213        *    * gl_SecondaryColor
4214        */
4215    } else if (state->is_version(130, 0)
4216               && (strcmp(var->name, "gl_FrontColor") == 0
4217                   || strcmp(var->name, "gl_BackColor") == 0
4218                   || strcmp(var->name, "gl_FrontSecondaryColor") == 0
4219                   || strcmp(var->name, "gl_BackSecondaryColor") == 0
4220                   || strcmp(var->name, "gl_Color") == 0
4221                   || strcmp(var->name, "gl_SecondaryColor") == 0)
4222               && earlier->type == var->type
4223               && earlier->data.mode == var->data.mode) {
4224       earlier->data.interpolation = var->data.interpolation;
4225 
4226       /* Layout qualifiers for gl_FragDepth. */
4227    } else if ((state->is_version(420, 0) ||
4228                state->AMD_conservative_depth_enable ||
4229                state->ARB_conservative_depth_enable)
4230               && strcmp(var->name, "gl_FragDepth") == 0
4231               && earlier->type == var->type
4232               && earlier->data.mode == var->data.mode) {
4233 
4234       /** From the AMD_conservative_depth spec:
4235        *     Within any shader, the first redeclarations of gl_FragDepth
4236        *     must appear before any use of gl_FragDepth.
4237        */
4238       if (earlier->data.used) {
4239          _mesa_glsl_error(&loc, state,
4240                           "the first redeclaration of gl_FragDepth "
4241                           "must appear before any use of gl_FragDepth");
4242       }
4243 
4244       /* Prevent inconsistent redeclaration of depth layout qualifier. */
4245       if (earlier->data.depth_layout != ir_depth_layout_none
4246           && earlier->data.depth_layout != var->data.depth_layout) {
4247             _mesa_glsl_error(&loc, state,
4248                              "gl_FragDepth: depth layout is declared here "
4249                              "as '%s, but it was previously declared as "
4250                              "'%s'",
4251                              depth_layout_string(var->data.depth_layout),
4252                              depth_layout_string(earlier->data.depth_layout));
4253       }
4254 
4255       earlier->data.depth_layout = var->data.depth_layout;
4256 
4257    } else if (state->has_framebuffer_fetch() &&
4258               strcmp(var->name, "gl_LastFragData") == 0 &&
4259               var->type == earlier->type &&
4260               var->data.mode == ir_var_auto) {
4261       /* According to the EXT_shader_framebuffer_fetch spec:
4262        *
4263        *   "By default, gl_LastFragData is declared with the mediump precision
4264        *    qualifier. This can be changed by redeclaring the corresponding
4265        *    variables with the desired precision qualifier."
4266        */
4267       earlier->data.precision = var->data.precision;
4268 
4269    } else if (earlier->data.how_declared == ir_var_declared_implicitly &&
4270               state->allow_builtin_variable_redeclaration) {
4271       /* Allow verbatim redeclarations of built-in variables. Not explicitly
4272        * valid, but some applications do it.
4273        */
4274       if (earlier->data.mode != var->data.mode &&
4275           !(earlier->data.mode == ir_var_system_value &&
4276             var->data.mode == ir_var_shader_in)) {
4277          _mesa_glsl_error(&loc, state,
4278                           "redeclaration of `%s' with incorrect qualifiers",
4279                           var->name);
4280       } else if (earlier->type != var->type) {
4281          _mesa_glsl_error(&loc, state,
4282                           "redeclaration of `%s' has incorrect type",
4283                           var->name);
4284       }
4285    } else if (allow_all_redeclarations) {
4286       if (earlier->data.mode != var->data.mode) {
4287          _mesa_glsl_error(&loc, state,
4288                           "redeclaration of `%s' with incorrect qualifiers",
4289                           var->name);
4290       } else if (earlier->type != var->type) {
4291          _mesa_glsl_error(&loc, state,
4292                           "redeclaration of `%s' has incorrect type",
4293                           var->name);
4294       }
4295    } else {
4296       _mesa_glsl_error(&loc, state, "`%s' redeclared", var->name);
4297    }
4298 
4299    return earlier;
4300 }
4301 
4302 /**
4303  * Generate the IR for an initializer in a variable declaration
4304  */
4305 static ir_rvalue *
process_initializer(ir_variable * var,ast_declaration * decl,ast_fully_specified_type * type,exec_list * initializer_instructions,struct _mesa_glsl_parse_state * state)4306 process_initializer(ir_variable *var, ast_declaration *decl,
4307                     ast_fully_specified_type *type,
4308                     exec_list *initializer_instructions,
4309                     struct _mesa_glsl_parse_state *state)
4310 {
4311    void *mem_ctx = state;
4312    ir_rvalue *result = NULL;
4313 
4314    YYLTYPE initializer_loc = decl->initializer->get_location();
4315 
4316    /* From page 24 (page 30 of the PDF) of the GLSL 1.10 spec:
4317     *
4318     *    "All uniform variables are read-only and are initialized either
4319     *    directly by an application via API commands, or indirectly by
4320     *    OpenGL."
4321     */
4322    if (var->data.mode == ir_var_uniform) {
4323       state->check_version(120, 0, &initializer_loc,
4324                            "cannot initialize uniform %s",
4325                            var->name);
4326    }
4327 
4328    /* Section 4.3.7 "Buffer Variables" of the GLSL 4.30 spec:
4329     *
4330     *    "Buffer variables cannot have initializers."
4331     */
4332    if (var->data.mode == ir_var_shader_storage) {
4333       _mesa_glsl_error(&initializer_loc, state,
4334                        "cannot initialize buffer variable %s",
4335                        var->name);
4336    }
4337 
4338    /* From section 4.1.7 of the GLSL 4.40 spec:
4339     *
4340     *    "Opaque variables [...] are initialized only through the
4341     *     OpenGL API; they cannot be declared with an initializer in a
4342     *     shader."
4343     *
4344     * From section 4.1.7 of the ARB_bindless_texture spec:
4345     *
4346     *    "Samplers may be declared as shader inputs and outputs, as uniform
4347     *     variables, as temporary variables, and as function parameters."
4348     *
4349     * From section 4.1.X of the ARB_bindless_texture spec:
4350     *
4351     *    "Images may be declared as shader inputs and outputs, as uniform
4352     *     variables, as temporary variables, and as function parameters."
4353     */
4354    if (var->type->contains_atomic() ||
4355        (!state->has_bindless() && var->type->contains_opaque())) {
4356       _mesa_glsl_error(&initializer_loc, state,
4357                        "cannot initialize %s variable %s",
4358                        var->name, state->has_bindless() ? "atomic" : "opaque");
4359    }
4360 
4361    if ((var->data.mode == ir_var_shader_in) && (state->current_function == NULL)) {
4362       _mesa_glsl_error(&initializer_loc, state,
4363                        "cannot initialize %s shader input / %s %s",
4364                        _mesa_shader_stage_to_string(state->stage),
4365                        (state->stage == MESA_SHADER_VERTEX)
4366                        ? "attribute" : "varying",
4367                        var->name);
4368    }
4369 
4370    if (var->data.mode == ir_var_shader_out && state->current_function == NULL) {
4371       _mesa_glsl_error(&initializer_loc, state,
4372                        "cannot initialize %s shader output %s",
4373                        _mesa_shader_stage_to_string(state->stage),
4374                        var->name);
4375    }
4376 
4377    /* If the initializer is an ast_aggregate_initializer, recursively store
4378     * type information from the LHS into it, so that its hir() function can do
4379     * type checking.
4380     */
4381    if (decl->initializer->oper == ast_aggregate)
4382       _mesa_ast_set_aggregate_type(var->type, decl->initializer);
4383 
4384    ir_dereference *const lhs = new(state) ir_dereference_variable(var);
4385    ir_rvalue *rhs = decl->initializer->hir(initializer_instructions, state);
4386 
4387    /* Calculate the constant value if this is a const or uniform
4388     * declaration.
4389     *
4390     * Section 4.3 (Storage Qualifiers) of the GLSL ES 1.00.17 spec says:
4391     *
4392     *     "Declarations of globals without a storage qualifier, or with
4393     *     just the const qualifier, may include initializers, in which case
4394     *     they will be initialized before the first line of main() is
4395     *     executed.  Such initializers must be a constant expression."
4396     *
4397     * The same section of the GLSL ES 3.00.4 spec has similar language.
4398     */
4399    if (type->qualifier.flags.q.constant
4400        || type->qualifier.flags.q.uniform
4401        || (state->es_shader && state->current_function == NULL)) {
4402       ir_rvalue *new_rhs = validate_assignment(state, initializer_loc,
4403                                                lhs, rhs, true);
4404       if (new_rhs != NULL) {
4405          rhs = new_rhs;
4406 
4407          /* Section 4.3.3 (Constant Expressions) of the GLSL ES 3.00.4 spec
4408           * says:
4409           *
4410           *     "A constant expression is one of
4411           *
4412           *        ...
4413           *
4414           *        - an expression formed by an operator on operands that are
4415           *          all constant expressions, including getting an element of
4416           *          a constant array, or a field of a constant structure, or
4417           *          components of a constant vector.  However, the sequence
4418           *          operator ( , ) and the assignment operators ( =, +=, ...)
4419           *          are not included in the operators that can create a
4420           *          constant expression."
4421           *
4422           * Section 12.43 (Sequence operator and constant expressions) says:
4423           *
4424           *     "Should the following construct be allowed?
4425           *
4426           *         float a[2,3];
4427           *
4428           *     The expression within the brackets uses the sequence operator
4429           *     (',') and returns the integer 3 so the construct is declaring
4430           *     a single-dimensional array of size 3.  In some languages, the
4431           *     construct declares a two-dimensional array.  It would be
4432           *     preferable to make this construct illegal to avoid confusion.
4433           *
4434           *     One possibility is to change the definition of the sequence
4435           *     operator so that it does not return a constant-expression and
4436           *     hence cannot be used to declare an array size.
4437           *
4438           *     RESOLUTION: The result of a sequence operator is not a
4439           *     constant-expression."
4440           *
4441           * Section 4.3.3 (Constant Expressions) of the GLSL 4.30.9 spec
4442           * contains language almost identical to the section 4.3.3 in the
4443           * GLSL ES 3.00.4 spec.  This is a new limitation for these GLSL
4444           * versions.
4445           */
4446          ir_constant *constant_value =
4447             rhs->constant_expression_value(mem_ctx);
4448 
4449          if (!constant_value ||
4450              (state->is_version(430, 300) &&
4451               decl->initializer->has_sequence_subexpression())) {
4452             const char *const variable_mode =
4453                (type->qualifier.flags.q.constant)
4454                ? "const"
4455                : ((type->qualifier.flags.q.uniform) ? "uniform" : "global");
4456 
4457             /* If ARB_shading_language_420pack is enabled, initializers of
4458              * const-qualified local variables do not have to be constant
4459              * expressions. Const-qualified global variables must still be
4460              * initialized with constant expressions.
4461              */
4462             if (!state->has_420pack()
4463                 || state->current_function == NULL) {
4464                _mesa_glsl_error(& initializer_loc, state,
4465                                 "initializer of %s variable `%s' must be a "
4466                                 "constant expression",
4467                                 variable_mode,
4468                                 decl->identifier);
4469                if (var->type->is_numeric()) {
4470                   /* Reduce cascading errors. */
4471                   var->constant_value = type->qualifier.flags.q.constant
4472                      ? ir_constant::zero(state, var->type) : NULL;
4473                }
4474             }
4475          } else {
4476             rhs = constant_value;
4477             var->constant_value = type->qualifier.flags.q.constant
4478                ? constant_value : NULL;
4479          }
4480       } else {
4481          if (var->type->is_numeric()) {
4482             /* Reduce cascading errors. */
4483             rhs = var->constant_value = type->qualifier.flags.q.constant
4484                ? ir_constant::zero(state, var->type) : NULL;
4485          }
4486       }
4487    }
4488 
4489    if (rhs && !rhs->type->is_error()) {
4490       bool temp = var->data.read_only;
4491       if (type->qualifier.flags.q.constant)
4492          var->data.read_only = false;
4493 
4494       /* Never emit code to initialize a uniform.
4495        */
4496       const glsl_type *initializer_type;
4497       if (!type->qualifier.flags.q.uniform) {
4498          do_assignment(initializer_instructions, state,
4499                        NULL,
4500                        lhs, rhs,
4501                        &result, true,
4502                        true,
4503                        type->get_location());
4504          initializer_type = result->type;
4505       } else
4506          initializer_type = rhs->type;
4507 
4508       var->constant_initializer = rhs->constant_expression_value(mem_ctx);
4509       var->data.has_initializer = true;
4510 
4511       /* If the declared variable is an unsized array, it must inherrit
4512        * its full type from the initializer.  A declaration such as
4513        *
4514        *     uniform float a[] = float[](1.0, 2.0, 3.0, 3.0);
4515        *
4516        * becomes
4517        *
4518        *     uniform float a[4] = float[](1.0, 2.0, 3.0, 3.0);
4519        *
4520        * The assignment generated in the if-statement (below) will also
4521        * automatically handle this case for non-uniforms.
4522        *
4523        * If the declared variable is not an array, the types must
4524        * already match exactly.  As a result, the type assignment
4525        * here can be done unconditionally.  For non-uniforms the call
4526        * to do_assignment can change the type of the initializer (via
4527        * the implicit conversion rules).  For uniforms the initializer
4528        * must be a constant expression, and the type of that expression
4529        * was validated above.
4530        */
4531       var->type = initializer_type;
4532 
4533       var->data.read_only = temp;
4534    }
4535 
4536    return result;
4537 }
4538 
4539 static void
validate_layout_qualifier_vertex_count(struct _mesa_glsl_parse_state * state,YYLTYPE loc,ir_variable * var,unsigned num_vertices,unsigned * size,const char * var_category)4540 validate_layout_qualifier_vertex_count(struct _mesa_glsl_parse_state *state,
4541                                        YYLTYPE loc, ir_variable *var,
4542                                        unsigned num_vertices,
4543                                        unsigned *size,
4544                                        const char *var_category)
4545 {
4546    if (var->type->is_unsized_array()) {
4547       /* Section 4.3.8.1 (Input Layout Qualifiers) of the GLSL 1.50 spec says:
4548        *
4549        *   All geometry shader input unsized array declarations will be
4550        *   sized by an earlier input layout qualifier, when present, as per
4551        *   the following table.
4552        *
4553        * Followed by a table mapping each allowed input layout qualifier to
4554        * the corresponding input length.
4555        *
4556        * Similarly for tessellation control shader outputs.
4557        */
4558       if (num_vertices != 0)
4559          var->type = glsl_type::get_array_instance(var->type->fields.array,
4560                                                    num_vertices);
4561    } else {
4562       /* Section 4.3.8.1 (Input Layout Qualifiers) of the GLSL 1.50 spec
4563        * includes the following examples of compile-time errors:
4564        *
4565        *   // code sequence within one shader...
4566        *   in vec4 Color1[];    // size unknown
4567        *   ...Color1.length()...// illegal, length() unknown
4568        *   in vec4 Color2[2];   // size is 2
4569        *   ...Color1.length()...// illegal, Color1 still has no size
4570        *   in vec4 Color3[3];   // illegal, input sizes are inconsistent
4571        *   layout(lines) in;    // legal, input size is 2, matching
4572        *   in vec4 Color4[3];   // illegal, contradicts layout
4573        *   ...
4574        *
4575        * To detect the case illustrated by Color3, we verify that the size of
4576        * an explicitly-sized array matches the size of any previously declared
4577        * explicitly-sized array.  To detect the case illustrated by Color4, we
4578        * verify that the size of an explicitly-sized array is consistent with
4579        * any previously declared input layout.
4580        */
4581       if (num_vertices != 0 && var->type->length != num_vertices) {
4582          _mesa_glsl_error(&loc, state,
4583                           "%s size contradicts previously declared layout "
4584                           "(size is %u, but layout requires a size of %u)",
4585                           var_category, var->type->length, num_vertices);
4586       } else if (*size != 0 && var->type->length != *size) {
4587          _mesa_glsl_error(&loc, state,
4588                           "%s sizes are inconsistent (size is %u, but a "
4589                           "previous declaration has size %u)",
4590                           var_category, var->type->length, *size);
4591       } else {
4592          *size = var->type->length;
4593       }
4594    }
4595 }
4596 
4597 static void
handle_tess_ctrl_shader_output_decl(struct _mesa_glsl_parse_state * state,YYLTYPE loc,ir_variable * var)4598 handle_tess_ctrl_shader_output_decl(struct _mesa_glsl_parse_state *state,
4599                                     YYLTYPE loc, ir_variable *var)
4600 {
4601    unsigned num_vertices = 0;
4602 
4603    if (state->tcs_output_vertices_specified) {
4604       if (!state->out_qualifier->vertices->
4605              process_qualifier_constant(state, "vertices",
4606                                         &num_vertices, false)) {
4607          return;
4608       }
4609 
4610       if (num_vertices > state->Const.MaxPatchVertices) {
4611          _mesa_glsl_error(&loc, state, "vertices (%d) exceeds "
4612                           "GL_MAX_PATCH_VERTICES", num_vertices);
4613          return;
4614       }
4615    }
4616 
4617    if (!var->type->is_array() && !var->data.patch) {
4618       _mesa_glsl_error(&loc, state,
4619                        "tessellation control shader outputs must be arrays");
4620 
4621       /* To avoid cascading failures, short circuit the checks below. */
4622       return;
4623    }
4624 
4625    if (var->data.patch)
4626       return;
4627 
4628    validate_layout_qualifier_vertex_count(state, loc, var, num_vertices,
4629                                           &state->tcs_output_size,
4630                                           "tessellation control shader output");
4631 }
4632 
4633 /**
4634  * Do additional processing necessary for tessellation control/evaluation shader
4635  * input declarations. This covers both interface block arrays and bare input
4636  * variables.
4637  */
4638 static void
handle_tess_shader_input_decl(struct _mesa_glsl_parse_state * state,YYLTYPE loc,ir_variable * var)4639 handle_tess_shader_input_decl(struct _mesa_glsl_parse_state *state,
4640                               YYLTYPE loc, ir_variable *var)
4641 {
4642    if (!var->type->is_array() && !var->data.patch) {
4643       _mesa_glsl_error(&loc, state,
4644                        "per-vertex tessellation shader inputs must be arrays");
4645       /* Avoid cascading failures. */
4646       return;
4647    }
4648 
4649    if (var->data.patch)
4650       return;
4651 
4652    /* The ARB_tessellation_shader spec says:
4653     *
4654     *    "Declaring an array size is optional.  If no size is specified, it
4655     *     will be taken from the implementation-dependent maximum patch size
4656     *     (gl_MaxPatchVertices).  If a size is specified, it must match the
4657     *     maximum patch size; otherwise, a compile or link error will occur."
4658     *
4659     * This text appears twice, once for TCS inputs, and again for TES inputs.
4660     */
4661    if (var->type->is_unsized_array()) {
4662       var->type = glsl_type::get_array_instance(var->type->fields.array,
4663             state->Const.MaxPatchVertices);
4664    } else if (var->type->length != state->Const.MaxPatchVertices) {
4665       _mesa_glsl_error(&loc, state,
4666                        "per-vertex tessellation shader input arrays must be "
4667                        "sized to gl_MaxPatchVertices (%d).",
4668                        state->Const.MaxPatchVertices);
4669    }
4670 }
4671 
4672 
4673 /**
4674  * Do additional processing necessary for geometry shader input declarations
4675  * (this covers both interface blocks arrays and bare input variables).
4676  */
4677 static void
handle_geometry_shader_input_decl(struct _mesa_glsl_parse_state * state,YYLTYPE loc,ir_variable * var)4678 handle_geometry_shader_input_decl(struct _mesa_glsl_parse_state *state,
4679                                   YYLTYPE loc, ir_variable *var)
4680 {
4681    unsigned num_vertices = 0;
4682 
4683    if (state->gs_input_prim_type_specified) {
4684       num_vertices = vertices_per_prim(state->in_qualifier->prim_type);
4685    }
4686 
4687    /* Geometry shader input variables must be arrays.  Caller should have
4688     * reported an error for this.
4689     */
4690    if (!var->type->is_array()) {
4691       assert(state->error);
4692 
4693       /* To avoid cascading failures, short circuit the checks below. */
4694       return;
4695    }
4696 
4697    validate_layout_qualifier_vertex_count(state, loc, var, num_vertices,
4698                                           &state->gs_input_size,
4699                                           "geometry shader input");
4700 }
4701 
4702 static void
validate_identifier(const char * identifier,YYLTYPE loc,struct _mesa_glsl_parse_state * state)4703 validate_identifier(const char *identifier, YYLTYPE loc,
4704                     struct _mesa_glsl_parse_state *state)
4705 {
4706    /* From page 15 (page 21 of the PDF) of the GLSL 1.10 spec,
4707     *
4708     *   "Identifiers starting with "gl_" are reserved for use by
4709     *   OpenGL, and may not be declared in a shader as either a
4710     *   variable or a function."
4711     */
4712    if (is_gl_identifier(identifier)) {
4713       _mesa_glsl_error(&loc, state,
4714                        "identifier `%s' uses reserved `gl_' prefix",
4715                        identifier);
4716    } else if (strstr(identifier, "__")) {
4717       /* From page 14 (page 20 of the PDF) of the GLSL 1.10
4718        * spec:
4719        *
4720        *     "In addition, all identifiers containing two
4721        *      consecutive underscores (__) are reserved as
4722        *      possible future keywords."
4723        *
4724        * The intention is that names containing __ are reserved for internal
4725        * use by the implementation, and names prefixed with GL_ are reserved
4726        * for use by Khronos.  Names simply containing __ are dangerous to use,
4727        * but should be allowed.
4728        *
4729        * A future version of the GLSL specification will clarify this.
4730        */
4731       _mesa_glsl_warning(&loc, state,
4732                          "identifier `%s' uses reserved `__' string",
4733                          identifier);
4734    }
4735 }
4736 
4737 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)4738 ast_declarator_list::hir(exec_list *instructions,
4739                          struct _mesa_glsl_parse_state *state)
4740 {
4741    void *ctx = state;
4742    const struct glsl_type *decl_type;
4743    const char *type_name = NULL;
4744    ir_rvalue *result = NULL;
4745    YYLTYPE loc = this->get_location();
4746 
4747    /* From page 46 (page 52 of the PDF) of the GLSL 1.50 spec:
4748     *
4749     *     "To ensure that a particular output variable is invariant, it is
4750     *     necessary to use the invariant qualifier. It can either be used to
4751     *     qualify a previously declared variable as being invariant
4752     *
4753     *         invariant gl_Position; // make existing gl_Position be invariant"
4754     *
4755     * In these cases the parser will set the 'invariant' flag in the declarator
4756     * list, and the type will be NULL.
4757     */
4758    if (this->invariant) {
4759       assert(this->type == NULL);
4760 
4761       if (state->current_function != NULL) {
4762          _mesa_glsl_error(& loc, state,
4763                           "all uses of `invariant' keyword must be at global "
4764                           "scope");
4765       }
4766 
4767       foreach_list_typed (ast_declaration, decl, link, &this->declarations) {
4768          assert(decl->array_specifier == NULL);
4769          assert(decl->initializer == NULL);
4770 
4771          ir_variable *const earlier =
4772             state->symbols->get_variable(decl->identifier);
4773          if (earlier == NULL) {
4774             _mesa_glsl_error(& loc, state,
4775                              "undeclared variable `%s' cannot be marked "
4776                              "invariant", decl->identifier);
4777          } else if (!is_allowed_invariant(earlier, state)) {
4778             _mesa_glsl_error(&loc, state,
4779                              "`%s' cannot be marked invariant; interfaces between "
4780                              "shader stages only.", decl->identifier);
4781          } else if (earlier->data.used) {
4782             _mesa_glsl_error(& loc, state,
4783                             "variable `%s' may not be redeclared "
4784                             "`invariant' after being used",
4785                             earlier->name);
4786          } else {
4787             earlier->data.invariant = true;
4788          }
4789       }
4790 
4791       /* Invariant redeclarations do not have r-values.
4792        */
4793       return NULL;
4794    }
4795 
4796    if (this->precise) {
4797       assert(this->type == NULL);
4798 
4799       foreach_list_typed (ast_declaration, decl, link, &this->declarations) {
4800          assert(decl->array_specifier == NULL);
4801          assert(decl->initializer == NULL);
4802 
4803          ir_variable *const earlier =
4804             state->symbols->get_variable(decl->identifier);
4805          if (earlier == NULL) {
4806             _mesa_glsl_error(& loc, state,
4807                              "undeclared variable `%s' cannot be marked "
4808                              "precise", decl->identifier);
4809          } else if (state->current_function != NULL &&
4810                     !state->symbols->name_declared_this_scope(decl->identifier)) {
4811             /* Note: we have to check if we're in a function, since
4812              * builtins are treated as having come from another scope.
4813              */
4814             _mesa_glsl_error(& loc, state,
4815                              "variable `%s' from an outer scope may not be "
4816                              "redeclared `precise' in this scope",
4817                              earlier->name);
4818          } else if (earlier->data.used) {
4819             _mesa_glsl_error(& loc, state,
4820                              "variable `%s' may not be redeclared "
4821                              "`precise' after being used",
4822                              earlier->name);
4823          } else {
4824             earlier->data.precise = true;
4825          }
4826       }
4827 
4828       /* Precise redeclarations do not have r-values either. */
4829       return NULL;
4830    }
4831 
4832    assert(this->type != NULL);
4833    assert(!this->invariant);
4834    assert(!this->precise);
4835 
4836    /* The type specifier may contain a structure definition.  Process that
4837     * before any of the variable declarations.
4838     */
4839    (void) this->type->specifier->hir(instructions, state);
4840 
4841    decl_type = this->type->glsl_type(& type_name, state);
4842 
4843    /* Section 4.3.7 "Buffer Variables" of the GLSL 4.30 spec:
4844     *    "Buffer variables may only be declared inside interface blocks
4845     *    (section 4.3.9 “Interface Blocks”), which are then referred to as
4846     *    shader storage blocks. It is a compile-time error to declare buffer
4847     *    variables at global scope (outside a block)."
4848     */
4849    if (type->qualifier.flags.q.buffer && !decl_type->is_interface()) {
4850       _mesa_glsl_error(&loc, state,
4851                        "buffer variables cannot be declared outside "
4852                        "interface blocks");
4853    }
4854 
4855    /* An offset-qualified atomic counter declaration sets the default
4856     * offset for the next declaration within the same atomic counter
4857     * buffer.
4858     */
4859    if (decl_type && decl_type->contains_atomic()) {
4860       if (type->qualifier.flags.q.explicit_binding &&
4861           type->qualifier.flags.q.explicit_offset) {
4862          unsigned qual_binding;
4863          unsigned qual_offset;
4864          if (process_qualifier_constant(state, &loc, "binding",
4865                                         type->qualifier.binding,
4866                                         &qual_binding)
4867              && process_qualifier_constant(state, &loc, "offset",
4868                                         type->qualifier.offset,
4869                                         &qual_offset)) {
4870             state->atomic_counter_offsets[qual_binding] = qual_offset;
4871          }
4872       }
4873 
4874       ast_type_qualifier allowed_atomic_qual_mask;
4875       allowed_atomic_qual_mask.flags.i = 0;
4876       allowed_atomic_qual_mask.flags.q.explicit_binding = 1;
4877       allowed_atomic_qual_mask.flags.q.explicit_offset = 1;
4878       allowed_atomic_qual_mask.flags.q.uniform = 1;
4879 
4880       type->qualifier.validate_flags(&loc, state, allowed_atomic_qual_mask,
4881                                      "invalid layout qualifier for",
4882                                      "atomic_uint");
4883    }
4884 
4885    if (this->declarations.is_empty()) {
4886       /* If there is no structure involved in the program text, there are two
4887        * possible scenarios:
4888        *
4889        * - The program text contained something like 'vec4;'.  This is an
4890        *   empty declaration.  It is valid but weird.  Emit a warning.
4891        *
4892        * - The program text contained something like 'S;' and 'S' is not the
4893        *   name of a known structure type.  This is both invalid and weird.
4894        *   Emit an error.
4895        *
4896        * - The program text contained something like 'mediump float;'
4897        *   when the programmer probably meant 'precision mediump
4898        *   float;' Emit a warning with a description of what they
4899        *   probably meant to do.
4900        *
4901        * Note that if decl_type is NULL and there is a structure involved,
4902        * there must have been some sort of error with the structure.  In this
4903        * case we assume that an error was already generated on this line of
4904        * code for the structure.  There is no need to generate an additional,
4905        * confusing error.
4906        */
4907       assert(this->type->specifier->structure == NULL || decl_type != NULL
4908              || state->error);
4909 
4910       if (decl_type == NULL) {
4911          _mesa_glsl_error(&loc, state,
4912                           "invalid type `%s' in empty declaration",
4913                           type_name);
4914       } else {
4915          if (decl_type->is_array()) {
4916             /* From Section 13.22 (Array Declarations) of the GLSL ES 3.2
4917              * spec:
4918              *
4919              *    "... any declaration that leaves the size undefined is
4920              *    disallowed as this would add complexity and there are no
4921              *    use-cases."
4922              */
4923             if (state->es_shader && decl_type->is_unsized_array()) {
4924                _mesa_glsl_error(&loc, state, "array size must be explicitly "
4925                                 "or implicitly defined");
4926             }
4927 
4928             /* From Section 4.12 (Empty Declarations) of the GLSL 4.5 spec:
4929              *
4930              *    "The combinations of types and qualifiers that cause
4931              *    compile-time or link-time errors are the same whether or not
4932              *    the declaration is empty."
4933              */
4934             validate_array_dimensions(decl_type, state, &loc);
4935          }
4936 
4937          if (decl_type->is_atomic_uint()) {
4938             /* Empty atomic counter declarations are allowed and useful
4939              * to set the default offset qualifier.
4940              */
4941             return NULL;
4942          } else if (this->type->qualifier.precision != ast_precision_none) {
4943             if (this->type->specifier->structure != NULL) {
4944                _mesa_glsl_error(&loc, state,
4945                                 "precision qualifiers can't be applied "
4946                                 "to structures");
4947             } else {
4948                static const char *const precision_names[] = {
4949                   "highp",
4950                   "highp",
4951                   "mediump",
4952                   "lowp"
4953                };
4954 
4955                _mesa_glsl_warning(&loc, state,
4956                                   "empty declaration with precision "
4957                                   "qualifier, to set the default precision, "
4958                                   "use `precision %s %s;'",
4959                                   precision_names[this->type->
4960                                      qualifier.precision],
4961                                   type_name);
4962             }
4963          } else if (this->type->specifier->structure == NULL) {
4964             _mesa_glsl_warning(&loc, state, "empty declaration");
4965          }
4966       }
4967    }
4968 
4969    foreach_list_typed (ast_declaration, decl, link, &this->declarations) {
4970       const struct glsl_type *var_type;
4971       ir_variable *var;
4972       const char *identifier = decl->identifier;
4973       /* FINISHME: Emit a warning if a variable declaration shadows a
4974        * FINISHME: declaration at a higher scope.
4975        */
4976 
4977       if ((decl_type == NULL) || decl_type->is_void()) {
4978          if (type_name != NULL) {
4979             _mesa_glsl_error(& loc, state,
4980                              "invalid type `%s' in declaration of `%s'",
4981                              type_name, decl->identifier);
4982          } else {
4983             _mesa_glsl_error(& loc, state,
4984                              "invalid type in declaration of `%s'",
4985                              decl->identifier);
4986          }
4987          continue;
4988       }
4989 
4990       if (this->type->qualifier.is_subroutine_decl()) {
4991          const glsl_type *t;
4992          const char *name;
4993 
4994          t = state->symbols->get_type(this->type->specifier->type_name);
4995          if (!t)
4996             _mesa_glsl_error(& loc, state,
4997                              "invalid type in declaration of `%s'",
4998                              decl->identifier);
4999          name = ralloc_asprintf(ctx, "%s_%s", _mesa_shader_stage_to_subroutine_prefix(state->stage), decl->identifier);
5000 
5001          identifier = name;
5002 
5003       }
5004       var_type = process_array_type(&loc, decl_type, decl->array_specifier,
5005                                     state);
5006 
5007       var = new(ctx) ir_variable(var_type, identifier, ir_var_auto);
5008 
5009       /* The 'varying in' and 'varying out' qualifiers can only be used with
5010        * ARB_geometry_shader4 and EXT_geometry_shader4, which we don't support
5011        * yet.
5012        */
5013       if (this->type->qualifier.flags.q.varying) {
5014          if (this->type->qualifier.flags.q.in) {
5015             _mesa_glsl_error(& loc, state,
5016                              "`varying in' qualifier in declaration of "
5017                              "`%s' only valid for geometry shaders using "
5018                              "ARB_geometry_shader4 or EXT_geometry_shader4",
5019                              decl->identifier);
5020          } else if (this->type->qualifier.flags.q.out) {
5021             _mesa_glsl_error(& loc, state,
5022                              "`varying out' qualifier in declaration of "
5023                              "`%s' only valid for geometry shaders using "
5024                              "ARB_geometry_shader4 or EXT_geometry_shader4",
5025                              decl->identifier);
5026          }
5027       }
5028 
5029       /* From page 22 (page 28 of the PDF) of the GLSL 1.10 specification;
5030        *
5031        *     "Global variables can only use the qualifiers const,
5032        *     attribute, uniform, or varying. Only one may be
5033        *     specified.
5034        *
5035        *     Local variables can only use the qualifier const."
5036        *
5037        * This is relaxed in GLSL 1.30 and GLSL ES 3.00.  It is also relaxed by
5038        * any extension that adds the 'layout' keyword.
5039        */
5040       if (!state->is_version(130, 300)
5041           && !state->has_explicit_attrib_location()
5042           && !state->has_separate_shader_objects()
5043           && !state->ARB_fragment_coord_conventions_enable) {
5044          if (this->type->qualifier.flags.q.out) {
5045             _mesa_glsl_error(& loc, state,
5046                              "`out' qualifier in declaration of `%s' "
5047                              "only valid for function parameters in %s",
5048                              decl->identifier, state->get_version_string());
5049          }
5050          if (this->type->qualifier.flags.q.in) {
5051             _mesa_glsl_error(& loc, state,
5052                              "`in' qualifier in declaration of `%s' "
5053                              "only valid for function parameters in %s",
5054                              decl->identifier, state->get_version_string());
5055          }
5056          /* FINISHME: Test for other invalid qualifiers. */
5057       }
5058 
5059       apply_type_qualifier_to_variable(& this->type->qualifier, var, state,
5060                                        & loc, false);
5061       apply_layout_qualifier_to_variable(&this->type->qualifier, var, state,
5062                                          &loc);
5063 
5064       if ((var->data.mode == ir_var_auto || var->data.mode == ir_var_temporary)
5065           && (var->type->is_numeric() || var->type->is_boolean())
5066           && state->zero_init) {
5067          const ir_constant_data data = { { 0 } };
5068          var->data.has_initializer = true;
5069          var->constant_initializer = new(var) ir_constant(var->type, &data);
5070       }
5071 
5072       if (this->type->qualifier.flags.q.invariant) {
5073          if (!is_allowed_invariant(var, state)) {
5074             _mesa_glsl_error(&loc, state,
5075                              "`%s' cannot be marked invariant; interfaces between "
5076                              "shader stages only", var->name);
5077          }
5078       }
5079 
5080       if (state->current_function != NULL) {
5081          const char *mode = NULL;
5082          const char *extra = "";
5083 
5084          /* There is no need to check for 'inout' here because the parser will
5085           * only allow that in function parameter lists.
5086           */
5087          if (this->type->qualifier.flags.q.attribute) {
5088             mode = "attribute";
5089          } else if (this->type->qualifier.is_subroutine_decl()) {
5090             mode = "subroutine uniform";
5091          } else if (this->type->qualifier.flags.q.uniform) {
5092             mode = "uniform";
5093          } else if (this->type->qualifier.flags.q.varying) {
5094             mode = "varying";
5095          } else if (this->type->qualifier.flags.q.in) {
5096             mode = "in";
5097             extra = " or in function parameter list";
5098          } else if (this->type->qualifier.flags.q.out) {
5099             mode = "out";
5100             extra = " or in function parameter list";
5101          }
5102 
5103          if (mode) {
5104             _mesa_glsl_error(& loc, state,
5105                              "%s variable `%s' must be declared at "
5106                              "global scope%s",
5107                              mode, var->name, extra);
5108          }
5109       } else if (var->data.mode == ir_var_shader_in) {
5110          var->data.read_only = true;
5111 
5112          if (state->stage == MESA_SHADER_VERTEX) {
5113             bool error_emitted = false;
5114 
5115             /* From page 31 (page 37 of the PDF) of the GLSL 1.50 spec:
5116              *
5117              *    "Vertex shader inputs can only be float, floating-point
5118              *    vectors, matrices, signed and unsigned integers and integer
5119              *    vectors. Vertex shader inputs can also form arrays of these
5120              *    types, but not structures."
5121              *
5122              * From page 31 (page 27 of the PDF) of the GLSL 1.30 spec:
5123              *
5124              *    "Vertex shader inputs can only be float, floating-point
5125              *    vectors, matrices, signed and unsigned integers and integer
5126              *    vectors. They cannot be arrays or structures."
5127              *
5128              * From page 23 (page 29 of the PDF) of the GLSL 1.20 spec:
5129              *
5130              *    "The attribute qualifier can be used only with float,
5131              *    floating-point vectors, and matrices. Attribute variables
5132              *    cannot be declared as arrays or structures."
5133              *
5134              * From page 33 (page 39 of the PDF) of the GLSL ES 3.00 spec:
5135              *
5136              *    "Vertex shader inputs can only be float, floating-point
5137              *    vectors, matrices, signed and unsigned integers and integer
5138              *    vectors. Vertex shader inputs cannot be arrays or
5139              *    structures."
5140              *
5141              * From section 4.3.4 of the ARB_bindless_texture spec:
5142              *
5143              *    "(modify third paragraph of the section to allow sampler and
5144              *    image types) ...  Vertex shader inputs can only be float,
5145              *    single-precision floating-point scalars, single-precision
5146              *    floating-point vectors, matrices, signed and unsigned
5147              *    integers and integer vectors, sampler and image types."
5148              */
5149             const glsl_type *check_type = var->type->without_array();
5150 
5151             switch (check_type->base_type) {
5152             case GLSL_TYPE_FLOAT:
5153             break;
5154             case GLSL_TYPE_UINT64:
5155             case GLSL_TYPE_INT64:
5156                break;
5157             case GLSL_TYPE_UINT:
5158             case GLSL_TYPE_INT:
5159                if (state->is_version(120, 300))
5160                   break;
5161             case GLSL_TYPE_DOUBLE:
5162                if (check_type->is_double() && (state->is_version(410, 0) || state->ARB_vertex_attrib_64bit_enable))
5163                   break;
5164             case GLSL_TYPE_SAMPLER:
5165                if (check_type->is_sampler() && state->has_bindless())
5166                   break;
5167             case GLSL_TYPE_IMAGE:
5168                if (check_type->is_image() && state->has_bindless())
5169                   break;
5170             /* FALLTHROUGH */
5171             default:
5172                _mesa_glsl_error(& loc, state,
5173                                 "vertex shader input / attribute cannot have "
5174                                 "type %s`%s'",
5175                                 var->type->is_array() ? "array of " : "",
5176                                 check_type->name);
5177                error_emitted = true;
5178             }
5179 
5180             if (!error_emitted && var->type->is_array() &&
5181                 !state->check_version(150, 0, &loc,
5182                                       "vertex shader input / attribute "
5183                                       "cannot have array type")) {
5184                error_emitted = true;
5185             }
5186          } else if (state->stage == MESA_SHADER_GEOMETRY) {
5187             /* From section 4.3.4 (Inputs) of the GLSL 1.50 spec:
5188              *
5189              *     Geometry shader input variables get the per-vertex values
5190              *     written out by vertex shader output variables of the same
5191              *     names. Since a geometry shader operates on a set of
5192              *     vertices, each input varying variable (or input block, see
5193              *     interface blocks below) needs to be declared as an array.
5194              */
5195             if (!var->type->is_array()) {
5196                _mesa_glsl_error(&loc, state,
5197                                 "geometry shader inputs must be arrays");
5198             }
5199 
5200             handle_geometry_shader_input_decl(state, loc, var);
5201          } else if (state->stage == MESA_SHADER_FRAGMENT) {
5202             /* From section 4.3.4 (Input Variables) of the GLSL ES 3.10 spec:
5203              *
5204              *     It is a compile-time error to declare a fragment shader
5205              *     input with, or that contains, any of the following types:
5206              *
5207              *     * A boolean type
5208              *     * An opaque type
5209              *     * An array of arrays
5210              *     * An array of structures
5211              *     * A structure containing an array
5212              *     * A structure containing a structure
5213              */
5214             if (state->es_shader) {
5215                const glsl_type *check_type = var->type->without_array();
5216                if (check_type->is_boolean() ||
5217                    check_type->contains_opaque()) {
5218                   _mesa_glsl_error(&loc, state,
5219                                    "fragment shader input cannot have type %s",
5220                                    check_type->name);
5221                }
5222                if (var->type->is_array() &&
5223                    var->type->fields.array->is_array()) {
5224                   _mesa_glsl_error(&loc, state,
5225                                    "%s shader output "
5226                                    "cannot have an array of arrays",
5227                                    _mesa_shader_stage_to_string(state->stage));
5228                }
5229                if (var->type->is_array() &&
5230                    var->type->fields.array->is_record()) {
5231                   _mesa_glsl_error(&loc, state,
5232                                    "fragment shader input "
5233                                    "cannot have an array of structs");
5234                }
5235                if (var->type->is_record()) {
5236                   for (unsigned i = 0; i < var->type->length; i++) {
5237                      if (var->type->fields.structure[i].type->is_array() ||
5238                          var->type->fields.structure[i].type->is_record())
5239                         _mesa_glsl_error(&loc, state,
5240                                          "fragment shader input cannot have "
5241                                          "a struct that contains an "
5242                                          "array or struct");
5243                   }
5244                }
5245             }
5246          } else if (state->stage == MESA_SHADER_TESS_CTRL ||
5247                     state->stage == MESA_SHADER_TESS_EVAL) {
5248             handle_tess_shader_input_decl(state, loc, var);
5249          }
5250       } else if (var->data.mode == ir_var_shader_out) {
5251          const glsl_type *check_type = var->type->without_array();
5252 
5253          /* From section 4.3.6 (Output variables) of the GLSL 4.40 spec:
5254           *
5255           *     It is a compile-time error to declare a fragment shader output
5256           *     that contains any of the following:
5257           *
5258           *     * A Boolean type (bool, bvec2 ...)
5259           *     * A double-precision scalar or vector (double, dvec2 ...)
5260           *     * An opaque type
5261           *     * Any matrix type
5262           *     * A structure
5263           */
5264          if (state->stage == MESA_SHADER_FRAGMENT) {
5265             if (check_type->is_record() || check_type->is_matrix())
5266                _mesa_glsl_error(&loc, state,
5267                                 "fragment shader output "
5268                                 "cannot have struct or matrix type");
5269             switch (check_type->base_type) {
5270             case GLSL_TYPE_UINT:
5271             case GLSL_TYPE_INT:
5272             case GLSL_TYPE_FLOAT:
5273                break;
5274             default:
5275                _mesa_glsl_error(&loc, state,
5276                                 "fragment shader output cannot have "
5277                                 "type %s", check_type->name);
5278             }
5279          }
5280 
5281          /* From section 4.3.6 (Output Variables) of the GLSL ES 3.10 spec:
5282           *
5283           *     It is a compile-time error to declare a vertex shader output
5284           *     with, or that contains, any of the following types:
5285           *
5286           *     * A boolean type
5287           *     * An opaque type
5288           *     * An array of arrays
5289           *     * An array of structures
5290           *     * A structure containing an array
5291           *     * A structure containing a structure
5292           *
5293           *     It is a compile-time error to declare a fragment shader output
5294           *     with, or that contains, any of the following types:
5295           *
5296           *     * A boolean type
5297           *     * An opaque type
5298           *     * A matrix
5299           *     * A structure
5300           *     * An array of array
5301           *
5302           * ES 3.20 updates this to apply to tessellation and geometry shaders
5303           * as well.  Because there are per-vertex arrays in the new stages,
5304           * it strikes the "array of..." rules and replaces them with these:
5305           *
5306           *     * For per-vertex-arrayed variables (applies to tessellation
5307           *       control, tessellation evaluation and geometry shaders):
5308           *
5309           *       * Per-vertex-arrayed arrays of arrays
5310           *       * Per-vertex-arrayed arrays of structures
5311           *
5312           *     * For non-per-vertex-arrayed variables:
5313           *
5314           *       * An array of arrays
5315           *       * An array of structures
5316           *
5317           * which basically says to unwrap the per-vertex aspect and apply
5318           * the old rules.
5319           */
5320          if (state->es_shader) {
5321             if (var->type->is_array() &&
5322                 var->type->fields.array->is_array()) {
5323                _mesa_glsl_error(&loc, state,
5324                                 "%s shader output "
5325                                 "cannot have an array of arrays",
5326                                 _mesa_shader_stage_to_string(state->stage));
5327             }
5328             if (state->stage <= MESA_SHADER_GEOMETRY) {
5329                const glsl_type *type = var->type;
5330 
5331                if (state->stage == MESA_SHADER_TESS_CTRL &&
5332                    !var->data.patch && var->type->is_array()) {
5333                   type = var->type->fields.array;
5334                }
5335 
5336                if (type->is_array() && type->fields.array->is_record()) {
5337                   _mesa_glsl_error(&loc, state,
5338                                    "%s shader output cannot have "
5339                                    "an array of structs",
5340                                    _mesa_shader_stage_to_string(state->stage));
5341                }
5342                if (type->is_record()) {
5343                   for (unsigned i = 0; i < type->length; i++) {
5344                      if (type->fields.structure[i].type->is_array() ||
5345                          type->fields.structure[i].type->is_record())
5346                         _mesa_glsl_error(&loc, state,
5347                                          "%s shader output cannot have a "
5348                                          "struct that contains an "
5349                                          "array or struct",
5350                                          _mesa_shader_stage_to_string(state->stage));
5351                   }
5352                }
5353             }
5354          }
5355 
5356          if (state->stage == MESA_SHADER_TESS_CTRL) {
5357             handle_tess_ctrl_shader_output_decl(state, loc, var);
5358          }
5359       } else if (var->type->contains_subroutine()) {
5360          /* declare subroutine uniforms as hidden */
5361          var->data.how_declared = ir_var_hidden;
5362       }
5363 
5364       /* From section 4.3.4 of the GLSL 4.00 spec:
5365        *    "Input variables may not be declared using the patch in qualifier
5366        *    in tessellation control or geometry shaders."
5367        *
5368        * From section 4.3.6 of the GLSL 4.00 spec:
5369        *    "It is an error to use patch out in a vertex, tessellation
5370        *    evaluation, or geometry shader."
5371        *
5372        * This doesn't explicitly forbid using them in a fragment shader, but
5373        * that's probably just an oversight.
5374        */
5375       if (state->stage != MESA_SHADER_TESS_EVAL
5376           && this->type->qualifier.flags.q.patch
5377           && this->type->qualifier.flags.q.in) {
5378 
5379          _mesa_glsl_error(&loc, state, "'patch in' can only be used in a "
5380                           "tessellation evaluation shader");
5381       }
5382 
5383       if (state->stage != MESA_SHADER_TESS_CTRL
5384           && this->type->qualifier.flags.q.patch
5385           && this->type->qualifier.flags.q.out) {
5386 
5387          _mesa_glsl_error(&loc, state, "'patch out' can only be used in a "
5388                           "tessellation control shader");
5389       }
5390 
5391       /* Precision qualifiers exists only in GLSL versions 1.00 and >= 1.30.
5392        */
5393       if (this->type->qualifier.precision != ast_precision_none) {
5394          state->check_precision_qualifiers_allowed(&loc);
5395       }
5396 
5397       if (this->type->qualifier.precision != ast_precision_none &&
5398           !precision_qualifier_allowed(var->type)) {
5399          _mesa_glsl_error(&loc, state,
5400                           "precision qualifiers apply only to floating point"
5401                           ", integer and opaque types");
5402       }
5403 
5404       /* From section 4.1.7 of the GLSL 4.40 spec:
5405        *
5406        *    "[Opaque types] can only be declared as function
5407        *     parameters or uniform-qualified variables."
5408        *
5409        * From section 4.1.7 of the ARB_bindless_texture spec:
5410        *
5411        *    "Samplers may be declared as shader inputs and outputs, as uniform
5412        *     variables, as temporary variables, and as function parameters."
5413        *
5414        * From section 4.1.X of the ARB_bindless_texture spec:
5415        *
5416        *    "Images may be declared as shader inputs and outputs, as uniform
5417        *     variables, as temporary variables, and as function parameters."
5418        */
5419       if (!this->type->qualifier.flags.q.uniform &&
5420           (var_type->contains_atomic() ||
5421            (!state->has_bindless() && var_type->contains_opaque()))) {
5422          _mesa_glsl_error(&loc, state,
5423                           "%s variables must be declared uniform",
5424                           state->has_bindless() ? "atomic" : "opaque");
5425       }
5426 
5427       /* Process the initializer and add its instructions to a temporary
5428        * list.  This list will be added to the instruction stream (below) after
5429        * the declaration is added.  This is done because in some cases (such as
5430        * redeclarations) the declaration may not actually be added to the
5431        * instruction stream.
5432        */
5433       exec_list initializer_instructions;
5434 
5435       /* Examine var name here since var may get deleted in the next call */
5436       bool var_is_gl_id = is_gl_identifier(var->name);
5437 
5438       bool is_redeclaration;
5439       var = get_variable_being_redeclared(&var, decl->get_location(), state,
5440                                           false /* allow_all_redeclarations */,
5441                                           &is_redeclaration);
5442       if (is_redeclaration) {
5443          if (var_is_gl_id &&
5444              var->data.how_declared == ir_var_declared_in_block) {
5445             _mesa_glsl_error(&loc, state,
5446                              "`%s' has already been redeclared using "
5447                              "gl_PerVertex", var->name);
5448          }
5449          var->data.how_declared = ir_var_declared_normally;
5450       }
5451 
5452       if (decl->initializer != NULL) {
5453          result = process_initializer(var,
5454                                       decl, this->type,
5455                                       &initializer_instructions, state);
5456       } else {
5457          validate_array_dimensions(var_type, state, &loc);
5458       }
5459 
5460       /* From page 23 (page 29 of the PDF) of the GLSL 1.10 spec:
5461        *
5462        *     "It is an error to write to a const variable outside of
5463        *      its declaration, so they must be initialized when
5464        *      declared."
5465        */
5466       if (this->type->qualifier.flags.q.constant && decl->initializer == NULL) {
5467          _mesa_glsl_error(& loc, state,
5468                           "const declaration of `%s' must be initialized",
5469                           decl->identifier);
5470       }
5471 
5472       if (state->es_shader) {
5473          const glsl_type *const t = var->type;
5474 
5475          /* Skip the unsized array check for TCS/TES/GS inputs & TCS outputs.
5476           *
5477           * The GL_OES_tessellation_shader spec says about inputs:
5478           *
5479           *    "Declaring an array size is optional. If no size is specified,
5480           *     it will be taken from the implementation-dependent maximum
5481           *     patch size (gl_MaxPatchVertices)."
5482           *
5483           * and about TCS outputs:
5484           *
5485           *    "If no size is specified, it will be taken from output patch
5486           *     size declared in the shader."
5487           *
5488           * The GL_OES_geometry_shader spec says:
5489           *
5490           *    "All geometry shader input unsized array declarations will be
5491           *     sized by an earlier input primitive layout qualifier, when
5492           *     present, as per the following table."
5493           */
5494          const bool implicitly_sized =
5495             (var->data.mode == ir_var_shader_in &&
5496              state->stage >= MESA_SHADER_TESS_CTRL &&
5497              state->stage <= MESA_SHADER_GEOMETRY) ||
5498             (var->data.mode == ir_var_shader_out &&
5499              state->stage == MESA_SHADER_TESS_CTRL);
5500 
5501          if (t->is_unsized_array() && !implicitly_sized)
5502             /* Section 10.17 of the GLSL ES 1.00 specification states that
5503              * unsized array declarations have been removed from the language.
5504              * Arrays that are sized using an initializer are still explicitly
5505              * sized.  However, GLSL ES 1.00 does not allow array
5506              * initializers.  That is only allowed in GLSL ES 3.00.
5507              *
5508              * Section 4.1.9 (Arrays) of the GLSL ES 3.00 spec says:
5509              *
5510              *     "An array type can also be formed without specifying a size
5511              *     if the definition includes an initializer:
5512              *
5513              *         float x[] = float[2] (1.0, 2.0);     // declares an array of size 2
5514              *         float y[] = float[] (1.0, 2.0, 3.0); // declares an array of size 3
5515              *
5516              *         float a[5];
5517              *         float b[] = a;"
5518              */
5519             _mesa_glsl_error(& loc, state,
5520                              "unsized array declarations are not allowed in "
5521                              "GLSL ES");
5522       }
5523 
5524       /* Section 4.4.6.1 Atomic Counter Layout Qualifiers of the GLSL 4.60 spec:
5525        *
5526        *    "It is a compile-time error to declare an unsized array of
5527        *     atomic_uint"
5528        */
5529       if (var->type->is_unsized_array() &&
5530           var->type->without_array()->base_type == GLSL_TYPE_ATOMIC_UINT) {
5531          _mesa_glsl_error(& loc, state,
5532                           "Unsized array of atomic_uint is not allowed");
5533       }
5534 
5535       /* If the declaration is not a redeclaration, there are a few additional
5536        * semantic checks that must be applied.  In addition, variable that was
5537        * created for the declaration should be added to the IR stream.
5538        */
5539       if (!is_redeclaration) {
5540          validate_identifier(decl->identifier, loc, state);
5541 
5542          /* Add the variable to the symbol table.  Note that the initializer's
5543           * IR was already processed earlier (though it hasn't been emitted
5544           * yet), without the variable in scope.
5545           *
5546           * This differs from most C-like languages, but it follows the GLSL
5547           * specification.  From page 28 (page 34 of the PDF) of the GLSL 1.50
5548           * spec:
5549           *
5550           *     "Within a declaration, the scope of a name starts immediately
5551           *     after the initializer if present or immediately after the name
5552           *     being declared if not."
5553           */
5554          if (!state->symbols->add_variable(var)) {
5555             YYLTYPE loc = this->get_location();
5556             _mesa_glsl_error(&loc, state, "name `%s' already taken in the "
5557                              "current scope", decl->identifier);
5558             continue;
5559          }
5560 
5561          /* Push the variable declaration to the top.  It means that all the
5562           * variable declarations will appear in a funny last-to-first order,
5563           * but otherwise we run into trouble if a function is prototyped, a
5564           * global var is decled, then the function is defined with usage of
5565           * the global var.  See glslparsertest's CorrectModule.frag.
5566           */
5567          instructions->push_head(var);
5568       }
5569 
5570       instructions->append_list(&initializer_instructions);
5571    }
5572 
5573 
5574    /* Generally, variable declarations do not have r-values.  However,
5575     * one is used for the declaration in
5576     *
5577     * while (bool b = some_condition()) {
5578     *   ...
5579     * }
5580     *
5581     * so we return the rvalue from the last seen declaration here.
5582     */
5583    return result;
5584 }
5585 
5586 
5587 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)5588 ast_parameter_declarator::hir(exec_list *instructions,
5589                               struct _mesa_glsl_parse_state *state)
5590 {
5591    void *ctx = state;
5592    const struct glsl_type *type;
5593    const char *name = NULL;
5594    YYLTYPE loc = this->get_location();
5595 
5596    type = this->type->glsl_type(& name, state);
5597 
5598    if (type == NULL) {
5599       if (name != NULL) {
5600          _mesa_glsl_error(& loc, state,
5601                           "invalid type `%s' in declaration of `%s'",
5602                           name, this->identifier);
5603       } else {
5604          _mesa_glsl_error(& loc, state,
5605                           "invalid type in declaration of `%s'",
5606                           this->identifier);
5607       }
5608 
5609       type = glsl_type::error_type;
5610    }
5611 
5612    /* From page 62 (page 68 of the PDF) of the GLSL 1.50 spec:
5613     *
5614     *    "Functions that accept no input arguments need not use void in the
5615     *    argument list because prototypes (or definitions) are required and
5616     *    therefore there is no ambiguity when an empty argument list "( )" is
5617     *    declared. The idiom "(void)" as a parameter list is provided for
5618     *    convenience."
5619     *
5620     * Placing this check here prevents a void parameter being set up
5621     * for a function, which avoids tripping up checks for main taking
5622     * parameters and lookups of an unnamed symbol.
5623     */
5624    if (type->is_void()) {
5625       if (this->identifier != NULL)
5626          _mesa_glsl_error(& loc, state,
5627                           "named parameter cannot have type `void'");
5628 
5629       is_void = true;
5630       return NULL;
5631    }
5632 
5633    if (formal_parameter && (this->identifier == NULL)) {
5634       _mesa_glsl_error(& loc, state, "formal parameter lacks a name");
5635       return NULL;
5636    }
5637 
5638    /* This only handles "vec4 foo[..]".  The earlier specifier->glsl_type(...)
5639     * call already handled the "vec4[..] foo" case.
5640     */
5641    type = process_array_type(&loc, type, this->array_specifier, state);
5642 
5643    if (!type->is_error() && type->is_unsized_array()) {
5644       _mesa_glsl_error(&loc, state, "arrays passed as parameters must have "
5645                        "a declared size");
5646       type = glsl_type::error_type;
5647    }
5648 
5649    is_void = false;
5650    ir_variable *var = new(ctx)
5651       ir_variable(type, this->identifier, ir_var_function_in);
5652 
5653    /* Apply any specified qualifiers to the parameter declaration.  Note that
5654     * for function parameters the default mode is 'in'.
5655     */
5656    apply_type_qualifier_to_variable(& this->type->qualifier, var, state, & loc,
5657                                     true);
5658 
5659    /* From section 4.1.7 of the GLSL 4.40 spec:
5660     *
5661     *   "Opaque variables cannot be treated as l-values; hence cannot
5662     *    be used as out or inout function parameters, nor can they be
5663     *    assigned into."
5664     *
5665     * From section 4.1.7 of the ARB_bindless_texture spec:
5666     *
5667     *   "Samplers can be used as l-values, so can be assigned into and used
5668     *    as "out" and "inout" function parameters."
5669     *
5670     * From section 4.1.X of the ARB_bindless_texture spec:
5671     *
5672     *   "Images can be used as l-values, so can be assigned into and used as
5673     *    "out" and "inout" function parameters."
5674     */
5675    if ((var->data.mode == ir_var_function_inout || var->data.mode == ir_var_function_out)
5676        && (type->contains_atomic() ||
5677            (!state->has_bindless() && type->contains_opaque()))) {
5678       _mesa_glsl_error(&loc, state, "out and inout parameters cannot "
5679                        "contain %s variables",
5680                        state->has_bindless() ? "atomic" : "opaque");
5681       type = glsl_type::error_type;
5682    }
5683 
5684    /* From page 39 (page 45 of the PDF) of the GLSL 1.10 spec:
5685     *
5686     *    "When calling a function, expressions that do not evaluate to
5687     *     l-values cannot be passed to parameters declared as out or inout."
5688     *
5689     * From page 32 (page 38 of the PDF) of the GLSL 1.10 spec:
5690     *
5691     *    "Other binary or unary expressions, non-dereferenced arrays,
5692     *     function names, swizzles with repeated fields, and constants
5693     *     cannot be l-values."
5694     *
5695     * So for GLSL 1.10, passing an array as an out or inout parameter is not
5696     * allowed.  This restriction is removed in GLSL 1.20, and in GLSL ES.
5697     */
5698    if ((var->data.mode == ir_var_function_inout || var->data.mode == ir_var_function_out)
5699        && type->is_array()
5700        && !state->check_version(120, 100, &loc,
5701                                 "arrays cannot be out or inout parameters")) {
5702       type = glsl_type::error_type;
5703    }
5704 
5705    instructions->push_tail(var);
5706 
5707    /* Parameter declarations do not have r-values.
5708     */
5709    return NULL;
5710 }
5711 
5712 
5713 void
parameters_to_hir(exec_list * ast_parameters,bool formal,exec_list * ir_parameters,_mesa_glsl_parse_state * state)5714 ast_parameter_declarator::parameters_to_hir(exec_list *ast_parameters,
5715                                             bool formal,
5716                                             exec_list *ir_parameters,
5717                                             _mesa_glsl_parse_state *state)
5718 {
5719    ast_parameter_declarator *void_param = NULL;
5720    unsigned count = 0;
5721 
5722    foreach_list_typed (ast_parameter_declarator, param, link, ast_parameters) {
5723       param->formal_parameter = formal;
5724       param->hir(ir_parameters, state);
5725 
5726       if (param->is_void)
5727          void_param = param;
5728 
5729       count++;
5730    }
5731 
5732    if ((void_param != NULL) && (count > 1)) {
5733       YYLTYPE loc = void_param->get_location();
5734 
5735       _mesa_glsl_error(& loc, state,
5736                        "`void' parameter must be only parameter");
5737    }
5738 }
5739 
5740 
5741 void
emit_function(_mesa_glsl_parse_state * state,ir_function * f)5742 emit_function(_mesa_glsl_parse_state *state, ir_function *f)
5743 {
5744    /* IR invariants disallow function declarations or definitions
5745     * nested within other function definitions.  But there is no
5746     * requirement about the relative order of function declarations
5747     * and definitions with respect to one another.  So simply insert
5748     * the new ir_function block at the end of the toplevel instruction
5749     * list.
5750     */
5751    state->toplevel_ir->push_tail(f);
5752 }
5753 
5754 
5755 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)5756 ast_function::hir(exec_list *instructions,
5757                   struct _mesa_glsl_parse_state *state)
5758 {
5759    void *ctx = state;
5760    ir_function *f = NULL;
5761    ir_function_signature *sig = NULL;
5762    exec_list hir_parameters;
5763    YYLTYPE loc = this->get_location();
5764 
5765    const char *const name = identifier;
5766 
5767    /* New functions are always added to the top-level IR instruction stream,
5768     * so this instruction list pointer is ignored.  See also emit_function
5769     * (called below).
5770     */
5771    (void) instructions;
5772 
5773    /* From page 21 (page 27 of the PDF) of the GLSL 1.20 spec,
5774     *
5775     *   "Function declarations (prototypes) cannot occur inside of functions;
5776     *   they must be at global scope, or for the built-in functions, outside
5777     *   the global scope."
5778     *
5779     * From page 27 (page 33 of the PDF) of the GLSL ES 1.00.16 spec,
5780     *
5781     *   "User defined functions may only be defined within the global scope."
5782     *
5783     * Note that this language does not appear in GLSL 1.10.
5784     */
5785    if ((state->current_function != NULL) &&
5786        state->is_version(120, 100)) {
5787       YYLTYPE loc = this->get_location();
5788       _mesa_glsl_error(&loc, state,
5789                        "declaration of function `%s' not allowed within "
5790                        "function body", name);
5791    }
5792 
5793    validate_identifier(name, this->get_location(), state);
5794 
5795    /* Convert the list of function parameters to HIR now so that they can be
5796     * used below to compare this function's signature with previously seen
5797     * signatures for functions with the same name.
5798     */
5799    ast_parameter_declarator::parameters_to_hir(& this->parameters,
5800                                                is_definition,
5801                                                & hir_parameters, state);
5802 
5803    const char *return_type_name;
5804    const glsl_type *return_type =
5805       this->return_type->glsl_type(& return_type_name, state);
5806 
5807    if (!return_type) {
5808       YYLTYPE loc = this->get_location();
5809       _mesa_glsl_error(&loc, state,
5810                        "function `%s' has undeclared return type `%s'",
5811                        name, return_type_name);
5812       return_type = glsl_type::error_type;
5813    }
5814 
5815    /* ARB_shader_subroutine states:
5816     *  "Subroutine declarations cannot be prototyped. It is an error to prepend
5817     *   subroutine(...) to a function declaration."
5818     */
5819    if (this->return_type->qualifier.subroutine_list && !is_definition) {
5820       YYLTYPE loc = this->get_location();
5821       _mesa_glsl_error(&loc, state,
5822                        "function declaration `%s' cannot have subroutine prepended",
5823                        name);
5824    }
5825 
5826    /* From page 56 (page 62 of the PDF) of the GLSL 1.30 spec:
5827     * "No qualifier is allowed on the return type of a function."
5828     */
5829    if (this->return_type->has_qualifiers(state)) {
5830       YYLTYPE loc = this->get_location();
5831       _mesa_glsl_error(& loc, state,
5832                        "function `%s' return type has qualifiers", name);
5833    }
5834 
5835    /* Section 6.1 (Function Definitions) of the GLSL 1.20 spec says:
5836     *
5837     *     "Arrays are allowed as arguments and as the return type. In both
5838     *     cases, the array must be explicitly sized."
5839     */
5840    if (return_type->is_unsized_array()) {
5841       YYLTYPE loc = this->get_location();
5842       _mesa_glsl_error(& loc, state,
5843                        "function `%s' return type array must be explicitly "
5844                        "sized", name);
5845    }
5846 
5847    /* From Section 6.1 (Function Definitions) of the GLSL 1.00 spec:
5848     *
5849     *     "Arrays are allowed as arguments, but not as the return type. [...]
5850     *      The return type can also be a structure if the structure does not
5851     *      contain an array."
5852     */
5853    if (state->language_version == 100 && return_type->contains_array()) {
5854       YYLTYPE loc = this->get_location();
5855       _mesa_glsl_error(& loc, state,
5856                        "function `%s' return type contains an array", name);
5857    }
5858 
5859    /* From section 4.1.7 of the GLSL 4.40 spec:
5860     *
5861     *    "[Opaque types] can only be declared as function parameters
5862     *     or uniform-qualified variables."
5863     *
5864     * The ARB_bindless_texture spec doesn't clearly state this, but as it says
5865     * "Replace Section 4.1.7 (Samplers), p. 25" and, "Replace Section 4.1.X,
5866     * (Images)", this should be allowed.
5867     */
5868    if (return_type->contains_atomic() ||
5869        (!state->has_bindless() && return_type->contains_opaque())) {
5870       YYLTYPE loc = this->get_location();
5871       _mesa_glsl_error(&loc, state,
5872                        "function `%s' return type can't contain an %s type",
5873                        name, state->has_bindless() ? "atomic" : "opaque");
5874    }
5875 
5876    /**/
5877    if (return_type->is_subroutine()) {
5878       YYLTYPE loc = this->get_location();
5879       _mesa_glsl_error(&loc, state,
5880                        "function `%s' return type can't be a subroutine type",
5881                        name);
5882    }
5883 
5884 
5885    /* Create an ir_function if one doesn't already exist. */
5886    f = state->symbols->get_function(name);
5887    if (f == NULL) {
5888       f = new(ctx) ir_function(name);
5889       if (!this->return_type->qualifier.is_subroutine_decl()) {
5890          if (!state->symbols->add_function(f)) {
5891             /* This function name shadows a non-function use of the same name. */
5892             YYLTYPE loc = this->get_location();
5893             _mesa_glsl_error(&loc, state, "function name `%s' conflicts with "
5894                              "non-function", name);
5895             return NULL;
5896          }
5897       }
5898       emit_function(state, f);
5899    }
5900 
5901    /* From GLSL ES 3.0 spec, chapter 6.1 "Function Definitions", page 71:
5902     *
5903     * "A shader cannot redefine or overload built-in functions."
5904     *
5905     * While in GLSL ES 1.0 specification, chapter 8 "Built-in Functions":
5906     *
5907     * "User code can overload the built-in functions but cannot redefine
5908     * them."
5909     */
5910    if (state->es_shader) {
5911       /* Local shader has no exact candidates; check the built-ins. */
5912       _mesa_glsl_initialize_builtin_functions();
5913       if (state->language_version >= 300 &&
5914           _mesa_glsl_has_builtin_function(state, name)) {
5915          YYLTYPE loc = this->get_location();
5916          _mesa_glsl_error(& loc, state,
5917                           "A shader cannot redefine or overload built-in "
5918                           "function `%s' in GLSL ES 3.00", name);
5919          return NULL;
5920       }
5921 
5922       if (state->language_version == 100) {
5923          ir_function_signature *sig =
5924             _mesa_glsl_find_builtin_function(state, name, &hir_parameters);
5925          if (sig && sig->is_builtin()) {
5926             _mesa_glsl_error(& loc, state,
5927                              "A shader cannot redefine built-in "
5928                              "function `%s' in GLSL ES 1.00", name);
5929          }
5930       }
5931    }
5932 
5933    /* Verify that this function's signature either doesn't match a previously
5934     * seen signature for a function with the same name, or, if a match is found,
5935     * that the previously seen signature does not have an associated definition.
5936     */
5937    if (state->es_shader || f->has_user_signature()) {
5938       sig = f->exact_matching_signature(state, &hir_parameters);
5939       if (sig != NULL) {
5940          const char *badvar = sig->qualifiers_match(&hir_parameters);
5941          if (badvar != NULL) {
5942             YYLTYPE loc = this->get_location();
5943 
5944             _mesa_glsl_error(&loc, state, "function `%s' parameter `%s' "
5945                              "qualifiers don't match prototype", name, badvar);
5946          }
5947 
5948          if (sig->return_type != return_type) {
5949             YYLTYPE loc = this->get_location();
5950 
5951             _mesa_glsl_error(&loc, state, "function `%s' return type doesn't "
5952                              "match prototype", name);
5953          }
5954 
5955          if (sig->is_defined) {
5956             if (is_definition) {
5957                YYLTYPE loc = this->get_location();
5958                _mesa_glsl_error(& loc, state, "function `%s' redefined", name);
5959             } else {
5960                /* We just encountered a prototype that exactly matches a
5961                 * function that's already been defined.  This is redundant,
5962                 * and we should ignore it.
5963                 */
5964                return NULL;
5965             }
5966          } else if (state->language_version == 100 && !is_definition) {
5967             /* From the GLSL 1.00 spec, section 4.2.7:
5968              *
5969              *     "A particular variable, structure or function declaration
5970              *      may occur at most once within a scope with the exception
5971              *      that a single function prototype plus the corresponding
5972              *      function definition are allowed."
5973              */
5974             YYLTYPE loc = this->get_location();
5975             _mesa_glsl_error(&loc, state, "function `%s' redeclared", name);
5976          }
5977       }
5978    }
5979 
5980    /* Verify the return type of main() */
5981    if (strcmp(name, "main") == 0) {
5982       if (! return_type->is_void()) {
5983          YYLTYPE loc = this->get_location();
5984 
5985          _mesa_glsl_error(& loc, state, "main() must return void");
5986       }
5987 
5988       if (!hir_parameters.is_empty()) {
5989          YYLTYPE loc = this->get_location();
5990 
5991          _mesa_glsl_error(& loc, state, "main() must not take any parameters");
5992       }
5993    }
5994 
5995    /* Finish storing the information about this new function in its signature.
5996     */
5997    if (sig == NULL) {
5998       sig = new(ctx) ir_function_signature(return_type);
5999       f->add_signature(sig);
6000    }
6001 
6002    sig->replace_parameters(&hir_parameters);
6003    signature = sig;
6004 
6005    if (this->return_type->qualifier.subroutine_list) {
6006       int idx;
6007 
6008       if (this->return_type->qualifier.flags.q.explicit_index) {
6009          unsigned qual_index;
6010          if (process_qualifier_constant(state, &loc, "index",
6011                                         this->return_type->qualifier.index,
6012                                         &qual_index)) {
6013             if (!state->has_explicit_uniform_location()) {
6014                _mesa_glsl_error(&loc, state, "subroutine index requires "
6015                                 "GL_ARB_explicit_uniform_location or "
6016                                 "GLSL 4.30");
6017             } else if (qual_index >= MAX_SUBROUTINES) {
6018                _mesa_glsl_error(&loc, state,
6019                                 "invalid subroutine index (%d) index must "
6020                                 "be a number between 0 and "
6021                                 "GL_MAX_SUBROUTINES - 1 (%d)", qual_index,
6022                                 MAX_SUBROUTINES - 1);
6023             } else {
6024                f->subroutine_index = qual_index;
6025             }
6026          }
6027       }
6028 
6029       f->num_subroutine_types = this->return_type->qualifier.subroutine_list->declarations.length();
6030       f->subroutine_types = ralloc_array(state, const struct glsl_type *,
6031                                          f->num_subroutine_types);
6032       idx = 0;
6033       foreach_list_typed(ast_declaration, decl, link, &this->return_type->qualifier.subroutine_list->declarations) {
6034          const struct glsl_type *type;
6035          /* the subroutine type must be already declared */
6036          type = state->symbols->get_type(decl->identifier);
6037          if (!type) {
6038             _mesa_glsl_error(& loc, state, "unknown type '%s' in subroutine function definition", decl->identifier);
6039          }
6040 
6041          for (int i = 0; i < state->num_subroutine_types; i++) {
6042             ir_function *fn = state->subroutine_types[i];
6043             ir_function_signature *tsig = NULL;
6044 
6045             if (strcmp(fn->name, decl->identifier))
6046                continue;
6047 
6048             tsig = fn->matching_signature(state, &sig->parameters,
6049                                           false);
6050             if (!tsig) {
6051                _mesa_glsl_error(& loc, state, "subroutine type mismatch '%s' - signatures do not match\n", decl->identifier);
6052             } else {
6053                if (tsig->return_type != sig->return_type) {
6054                   _mesa_glsl_error(& loc, state, "subroutine type mismatch '%s' - return types do not match\n", decl->identifier);
6055                }
6056             }
6057          }
6058          f->subroutine_types[idx++] = type;
6059       }
6060       state->subroutines = (ir_function **)reralloc(state, state->subroutines,
6061                                                     ir_function *,
6062                                                     state->num_subroutines + 1);
6063       state->subroutines[state->num_subroutines] = f;
6064       state->num_subroutines++;
6065 
6066    }
6067 
6068    if (this->return_type->qualifier.is_subroutine_decl()) {
6069       if (!state->symbols->add_type(this->identifier, glsl_type::get_subroutine_instance(this->identifier))) {
6070          _mesa_glsl_error(& loc, state, "type '%s' previously defined", this->identifier);
6071          return NULL;
6072       }
6073       state->subroutine_types = (ir_function **)reralloc(state, state->subroutine_types,
6074                                                          ir_function *,
6075                                                          state->num_subroutine_types + 1);
6076       state->subroutine_types[state->num_subroutine_types] = f;
6077       state->num_subroutine_types++;
6078 
6079       f->is_subroutine = true;
6080    }
6081 
6082    /* Function declarations (prototypes) do not have r-values.
6083     */
6084    return NULL;
6085 }
6086 
6087 
6088 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6089 ast_function_definition::hir(exec_list *instructions,
6090                              struct _mesa_glsl_parse_state *state)
6091 {
6092    prototype->is_definition = true;
6093    prototype->hir(instructions, state);
6094 
6095    ir_function_signature *signature = prototype->signature;
6096    if (signature == NULL)
6097       return NULL;
6098 
6099    assert(state->current_function == NULL);
6100    state->current_function = signature;
6101    state->found_return = false;
6102 
6103    /* Duplicate parameters declared in the prototype as concrete variables.
6104     * Add these to the symbol table.
6105     */
6106    state->symbols->push_scope();
6107    foreach_in_list(ir_variable, var, &signature->parameters) {
6108       assert(var->as_variable() != NULL);
6109 
6110       /* The only way a parameter would "exist" is if two parameters have
6111        * the same name.
6112        */
6113       if (state->symbols->name_declared_this_scope(var->name)) {
6114          YYLTYPE loc = this->get_location();
6115 
6116          _mesa_glsl_error(& loc, state, "parameter `%s' redeclared", var->name);
6117       } else {
6118          state->symbols->add_variable(var);
6119       }
6120    }
6121 
6122    /* Convert the body of the function to HIR. */
6123    this->body->hir(&signature->body, state);
6124    signature->is_defined = true;
6125 
6126    state->symbols->pop_scope();
6127 
6128    assert(state->current_function == signature);
6129    state->current_function = NULL;
6130 
6131    if (!signature->return_type->is_void() && !state->found_return) {
6132       YYLTYPE loc = this->get_location();
6133       _mesa_glsl_error(& loc, state, "function `%s' has non-void return type "
6134                        "%s, but no return statement",
6135                        signature->function_name(),
6136                        signature->return_type->name);
6137    }
6138 
6139    /* Function definitions do not have r-values.
6140     */
6141    return NULL;
6142 }
6143 
6144 
6145 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6146 ast_jump_statement::hir(exec_list *instructions,
6147                         struct _mesa_glsl_parse_state *state)
6148 {
6149    void *ctx = state;
6150 
6151    switch (mode) {
6152    case ast_return: {
6153       ir_return *inst;
6154       assert(state->current_function);
6155 
6156       if (opt_return_value) {
6157          ir_rvalue *ret = opt_return_value->hir(instructions, state);
6158 
6159          /* The value of the return type can be NULL if the shader says
6160           * 'return foo();' and foo() is a function that returns void.
6161           *
6162           * NOTE: The GLSL spec doesn't say that this is an error.  The type
6163           * of the return value is void.  If the return type of the function is
6164           * also void, then this should compile without error.  Seriously.
6165           */
6166          const glsl_type *const ret_type =
6167             (ret == NULL) ? glsl_type::void_type : ret->type;
6168 
6169          /* Implicit conversions are not allowed for return values prior to
6170           * ARB_shading_language_420pack.
6171           */
6172          if (state->current_function->return_type != ret_type) {
6173             YYLTYPE loc = this->get_location();
6174 
6175             if (state->has_420pack()) {
6176                if (!apply_implicit_conversion(state->current_function->return_type,
6177                                               ret, state)) {
6178                   _mesa_glsl_error(& loc, state,
6179                                    "could not implicitly convert return value "
6180                                    "to %s, in function `%s'",
6181                                    state->current_function->return_type->name,
6182                                    state->current_function->function_name());
6183                }
6184             } else {
6185                _mesa_glsl_error(& loc, state,
6186                                 "`return' with wrong type %s, in function `%s' "
6187                                 "returning %s",
6188                                 ret_type->name,
6189                                 state->current_function->function_name(),
6190                                 state->current_function->return_type->name);
6191             }
6192          } else if (state->current_function->return_type->base_type ==
6193                     GLSL_TYPE_VOID) {
6194             YYLTYPE loc = this->get_location();
6195 
6196             /* The ARB_shading_language_420pack, GLSL ES 3.0, and GLSL 4.20
6197              * specs add a clarification:
6198              *
6199              *    "A void function can only use return without a return argument, even if
6200              *     the return argument has void type. Return statements only accept values:
6201              *
6202              *         void func1() { }
6203              *         void func2() { return func1(); } // illegal return statement"
6204              */
6205             _mesa_glsl_error(& loc, state,
6206                              "void functions can only use `return' without a "
6207                              "return argument");
6208          }
6209 
6210          inst = new(ctx) ir_return(ret);
6211       } else {
6212          if (state->current_function->return_type->base_type !=
6213              GLSL_TYPE_VOID) {
6214             YYLTYPE loc = this->get_location();
6215 
6216             _mesa_glsl_error(& loc, state,
6217                              "`return' with no value, in function %s returning "
6218                              "non-void",
6219             state->current_function->function_name());
6220          }
6221          inst = new(ctx) ir_return;
6222       }
6223 
6224       state->found_return = true;
6225       instructions->push_tail(inst);
6226       break;
6227    }
6228 
6229    case ast_discard:
6230       if (state->stage != MESA_SHADER_FRAGMENT) {
6231          YYLTYPE loc = this->get_location();
6232 
6233          _mesa_glsl_error(& loc, state,
6234                           "`discard' may only appear in a fragment shader");
6235       }
6236       instructions->push_tail(new(ctx) ir_discard);
6237       break;
6238 
6239    case ast_break:
6240    case ast_continue:
6241       if (mode == ast_continue &&
6242           state->loop_nesting_ast == NULL) {
6243          YYLTYPE loc = this->get_location();
6244 
6245          _mesa_glsl_error(& loc, state, "continue may only appear in a loop");
6246       } else if (mode == ast_break &&
6247          state->loop_nesting_ast == NULL &&
6248          state->switch_state.switch_nesting_ast == NULL) {
6249          YYLTYPE loc = this->get_location();
6250 
6251          _mesa_glsl_error(& loc, state,
6252                           "break may only appear in a loop or a switch");
6253       } else {
6254          /* For a loop, inline the for loop expression again, since we don't
6255           * know where near the end of the loop body the normal copy of it is
6256           * going to be placed.  Same goes for the condition for a do-while
6257           * loop.
6258           */
6259          if (state->loop_nesting_ast != NULL &&
6260              mode == ast_continue && !state->switch_state.is_switch_innermost) {
6261             if (state->loop_nesting_ast->rest_expression) {
6262                state->loop_nesting_ast->rest_expression->hir(instructions,
6263                                                              state);
6264             }
6265             if (state->loop_nesting_ast->mode ==
6266                 ast_iteration_statement::ast_do_while) {
6267                state->loop_nesting_ast->condition_to_hir(instructions, state);
6268             }
6269          }
6270 
6271          if (state->switch_state.is_switch_innermost &&
6272              mode == ast_continue) {
6273             /* Set 'continue_inside' to true. */
6274             ir_rvalue *const true_val = new (ctx) ir_constant(true);
6275             ir_dereference_variable *deref_continue_inside_var =
6276                new(ctx) ir_dereference_variable(state->switch_state.continue_inside);
6277             instructions->push_tail(new(ctx) ir_assignment(deref_continue_inside_var,
6278                                                            true_val));
6279 
6280             /* Break out from the switch, continue for the loop will
6281              * be called right after switch. */
6282             ir_loop_jump *const jump =
6283                new(ctx) ir_loop_jump(ir_loop_jump::jump_break);
6284             instructions->push_tail(jump);
6285 
6286          } else if (state->switch_state.is_switch_innermost &&
6287              mode == ast_break) {
6288             /* Force break out of switch by inserting a break. */
6289             ir_loop_jump *const jump =
6290                new(ctx) ir_loop_jump(ir_loop_jump::jump_break);
6291             instructions->push_tail(jump);
6292          } else {
6293             ir_loop_jump *const jump =
6294                new(ctx) ir_loop_jump((mode == ast_break)
6295                   ? ir_loop_jump::jump_break
6296                   : ir_loop_jump::jump_continue);
6297             instructions->push_tail(jump);
6298          }
6299       }
6300 
6301       break;
6302    }
6303 
6304    /* Jump instructions do not have r-values.
6305     */
6306    return NULL;
6307 }
6308 
6309 
6310 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6311 ast_selection_statement::hir(exec_list *instructions,
6312                              struct _mesa_glsl_parse_state *state)
6313 {
6314    void *ctx = state;
6315 
6316    ir_rvalue *const condition = this->condition->hir(instructions, state);
6317 
6318    /* From page 66 (page 72 of the PDF) of the GLSL 1.50 spec:
6319     *
6320     *    "Any expression whose type evaluates to a Boolean can be used as the
6321     *    conditional expression bool-expression. Vector types are not accepted
6322     *    as the expression to if."
6323     *
6324     * The checks are separated so that higher quality diagnostics can be
6325     * generated for cases where both rules are violated.
6326     */
6327    if (!condition->type->is_boolean() || !condition->type->is_scalar()) {
6328       YYLTYPE loc = this->condition->get_location();
6329 
6330       _mesa_glsl_error(& loc, state, "if-statement condition must be scalar "
6331                        "boolean");
6332    }
6333 
6334    ir_if *const stmt = new(ctx) ir_if(condition);
6335 
6336    if (then_statement != NULL) {
6337       state->symbols->push_scope();
6338       then_statement->hir(& stmt->then_instructions, state);
6339       state->symbols->pop_scope();
6340    }
6341 
6342    if (else_statement != NULL) {
6343       state->symbols->push_scope();
6344       else_statement->hir(& stmt->else_instructions, state);
6345       state->symbols->pop_scope();
6346    }
6347 
6348    instructions->push_tail(stmt);
6349 
6350    /* if-statements do not have r-values.
6351     */
6352    return NULL;
6353 }
6354 
6355 
6356 struct case_label {
6357    /** Value of the case label. */
6358    unsigned value;
6359 
6360    /** Does this label occur after the default? */
6361    bool after_default;
6362 
6363    /**
6364     * AST for the case label.
6365     *
6366     * This is only used to generate error messages for duplicate labels.
6367     */
6368    ast_expression *ast;
6369 };
6370 
6371 /* Used for detection of duplicate case values, compare
6372  * given contents directly.
6373  */
6374 static bool
compare_case_value(const void * a,const void * b)6375 compare_case_value(const void *a, const void *b)
6376 {
6377    return ((struct case_label *) a)->value == ((struct case_label *) b)->value;
6378 }
6379 
6380 
6381 /* Used for detection of duplicate case values, just
6382  * returns key contents as is.
6383  */
6384 static unsigned
key_contents(const void * key)6385 key_contents(const void *key)
6386 {
6387    return ((struct case_label *) key)->value;
6388 }
6389 
6390 
6391 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6392 ast_switch_statement::hir(exec_list *instructions,
6393                           struct _mesa_glsl_parse_state *state)
6394 {
6395    void *ctx = state;
6396 
6397    ir_rvalue *const test_expression =
6398       this->test_expression->hir(instructions, state);
6399 
6400    /* From page 66 (page 55 of the PDF) of the GLSL 1.50 spec:
6401     *
6402     *    "The type of init-expression in a switch statement must be a
6403     *     scalar integer."
6404     */
6405    if (!test_expression->type->is_scalar() ||
6406        !test_expression->type->is_integer()) {
6407       YYLTYPE loc = this->test_expression->get_location();
6408 
6409       _mesa_glsl_error(& loc,
6410                        state,
6411                        "switch-statement expression must be scalar "
6412                        "integer");
6413       return NULL;
6414    }
6415 
6416    /* Track the switch-statement nesting in a stack-like manner.
6417     */
6418    struct glsl_switch_state saved = state->switch_state;
6419 
6420    state->switch_state.is_switch_innermost = true;
6421    state->switch_state.switch_nesting_ast = this;
6422    state->switch_state.labels_ht =
6423          _mesa_hash_table_create(NULL, key_contents,
6424                                  compare_case_value);
6425    state->switch_state.previous_default = NULL;
6426 
6427    /* Initalize is_fallthru state to false.
6428     */
6429    ir_rvalue *const is_fallthru_val = new (ctx) ir_constant(false);
6430    state->switch_state.is_fallthru_var =
6431       new(ctx) ir_variable(glsl_type::bool_type,
6432                            "switch_is_fallthru_tmp",
6433                            ir_var_temporary);
6434    instructions->push_tail(state->switch_state.is_fallthru_var);
6435 
6436    ir_dereference_variable *deref_is_fallthru_var =
6437       new(ctx) ir_dereference_variable(state->switch_state.is_fallthru_var);
6438    instructions->push_tail(new(ctx) ir_assignment(deref_is_fallthru_var,
6439                                                   is_fallthru_val));
6440 
6441    /* Initialize continue_inside state to false.
6442     */
6443    state->switch_state.continue_inside =
6444       new(ctx) ir_variable(glsl_type::bool_type,
6445                            "continue_inside_tmp",
6446                            ir_var_temporary);
6447    instructions->push_tail(state->switch_state.continue_inside);
6448 
6449    ir_rvalue *const false_val = new (ctx) ir_constant(false);
6450    ir_dereference_variable *deref_continue_inside_var =
6451       new(ctx) ir_dereference_variable(state->switch_state.continue_inside);
6452    instructions->push_tail(new(ctx) ir_assignment(deref_continue_inside_var,
6453                                                   false_val));
6454 
6455    state->switch_state.run_default =
6456       new(ctx) ir_variable(glsl_type::bool_type,
6457                              "run_default_tmp",
6458                              ir_var_temporary);
6459    instructions->push_tail(state->switch_state.run_default);
6460 
6461    /* Loop around the switch is used for flow control. */
6462    ir_loop * loop = new(ctx) ir_loop();
6463    instructions->push_tail(loop);
6464 
6465    /* Cache test expression.
6466     */
6467    test_to_hir(&loop->body_instructions, state);
6468 
6469    /* Emit code for body of switch stmt.
6470     */
6471    body->hir(&loop->body_instructions, state);
6472 
6473    /* Insert a break at the end to exit loop. */
6474    ir_loop_jump *jump = new(ctx) ir_loop_jump(ir_loop_jump::jump_break);
6475    loop->body_instructions.push_tail(jump);
6476 
6477    /* If we are inside loop, check if continue got called inside switch. */
6478    if (state->loop_nesting_ast != NULL) {
6479       ir_dereference_variable *deref_continue_inside =
6480          new(ctx) ir_dereference_variable(state->switch_state.continue_inside);
6481       ir_if *irif = new(ctx) ir_if(deref_continue_inside);
6482       ir_loop_jump *jump = new(ctx) ir_loop_jump(ir_loop_jump::jump_continue);
6483 
6484       if (state->loop_nesting_ast != NULL) {
6485          if (state->loop_nesting_ast->rest_expression) {
6486             state->loop_nesting_ast->rest_expression->hir(&irif->then_instructions,
6487                                                           state);
6488          }
6489          if (state->loop_nesting_ast->mode ==
6490              ast_iteration_statement::ast_do_while) {
6491             state->loop_nesting_ast->condition_to_hir(&irif->then_instructions, state);
6492          }
6493       }
6494       irif->then_instructions.push_tail(jump);
6495       instructions->push_tail(irif);
6496    }
6497 
6498    _mesa_hash_table_destroy(state->switch_state.labels_ht, NULL);
6499 
6500    state->switch_state = saved;
6501 
6502    /* Switch statements do not have r-values. */
6503    return NULL;
6504 }
6505 
6506 
6507 void
test_to_hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6508 ast_switch_statement::test_to_hir(exec_list *instructions,
6509                                   struct _mesa_glsl_parse_state *state)
6510 {
6511    void *ctx = state;
6512 
6513    /* set to true to avoid a duplicate "use of uninitialized variable" warning
6514     * on the switch test case. The first one would be already raised when
6515     * getting the test_expression at ast_switch_statement::hir
6516     */
6517    test_expression->set_is_lhs(true);
6518    /* Cache value of test expression. */
6519    ir_rvalue *const test_val = test_expression->hir(instructions, state);
6520 
6521    state->switch_state.test_var = new(ctx) ir_variable(test_val->type,
6522                                                        "switch_test_tmp",
6523                                                        ir_var_temporary);
6524    ir_dereference_variable *deref_test_var =
6525       new(ctx) ir_dereference_variable(state->switch_state.test_var);
6526 
6527    instructions->push_tail(state->switch_state.test_var);
6528    instructions->push_tail(new(ctx) ir_assignment(deref_test_var, test_val));
6529 }
6530 
6531 
6532 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6533 ast_switch_body::hir(exec_list *instructions,
6534                      struct _mesa_glsl_parse_state *state)
6535 {
6536    if (stmts != NULL)
6537       stmts->hir(instructions, state);
6538 
6539    /* Switch bodies do not have r-values. */
6540    return NULL;
6541 }
6542 
6543 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6544 ast_case_statement_list::hir(exec_list *instructions,
6545                              struct _mesa_glsl_parse_state *state)
6546 {
6547    exec_list default_case, after_default, tmp;
6548 
6549    foreach_list_typed (ast_case_statement, case_stmt, link, & this->cases) {
6550       case_stmt->hir(&tmp, state);
6551 
6552       /* Default case. */
6553       if (state->switch_state.previous_default && default_case.is_empty()) {
6554          default_case.append_list(&tmp);
6555          continue;
6556       }
6557 
6558       /* If default case found, append 'after_default' list. */
6559       if (!default_case.is_empty())
6560          after_default.append_list(&tmp);
6561       else
6562          instructions->append_list(&tmp);
6563    }
6564 
6565    /* Handle the default case. This is done here because default might not be
6566     * the last case. We need to add checks against following cases first to see
6567     * if default should be chosen or not.
6568     */
6569    if (!default_case.is_empty()) {
6570       struct hash_entry *entry;
6571       ir_factory body(instructions, state);
6572 
6573       ir_expression *cmp = NULL;
6574 
6575       hash_table_foreach(state->switch_state.labels_ht, entry) {
6576          const struct case_label *const l = (struct case_label *) entry->data;
6577 
6578          /* If the switch init-value is the value of one of the labels that
6579           * occurs after the default case, disable execution of the default
6580           * case.
6581           */
6582          if (l->after_default) {
6583             ir_constant *const cnst =
6584                state->switch_state.test_var->type->base_type == GLSL_TYPE_UINT
6585                ? body.constant(unsigned(l->value))
6586                : body.constant(int(l->value));
6587 
6588             cmp = cmp == NULL
6589                ? equal(cnst, state->switch_state.test_var)
6590                : logic_or(cmp, equal(cnst, state->switch_state.test_var));
6591          }
6592       }
6593 
6594       if (cmp != NULL)
6595          body.emit(assign(state->switch_state.run_default, logic_not(cmp)));
6596       else
6597          body.emit(assign(state->switch_state.run_default, body.constant(true)));
6598 
6599       /* Append default case and all cases after it. */
6600       instructions->append_list(&default_case);
6601       instructions->append_list(&after_default);
6602    }
6603 
6604    /* Case statements do not have r-values. */
6605    return NULL;
6606 }
6607 
6608 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6609 ast_case_statement::hir(exec_list *instructions,
6610                         struct _mesa_glsl_parse_state *state)
6611 {
6612    labels->hir(instructions, state);
6613 
6614    /* Guard case statements depending on fallthru state. */
6615    ir_dereference_variable *const deref_fallthru_guard =
6616       new(state) ir_dereference_variable(state->switch_state.is_fallthru_var);
6617    ir_if *const test_fallthru = new(state) ir_if(deref_fallthru_guard);
6618 
6619    foreach_list_typed (ast_node, stmt, link, & this->stmts)
6620       stmt->hir(& test_fallthru->then_instructions, state);
6621 
6622    instructions->push_tail(test_fallthru);
6623 
6624    /* Case statements do not have r-values. */
6625    return NULL;
6626 }
6627 
6628 
6629 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6630 ast_case_label_list::hir(exec_list *instructions,
6631                          struct _mesa_glsl_parse_state *state)
6632 {
6633    foreach_list_typed (ast_case_label, label, link, & this->labels)
6634       label->hir(instructions, state);
6635 
6636    /* Case labels do not have r-values. */
6637    return NULL;
6638 }
6639 
6640 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6641 ast_case_label::hir(exec_list *instructions,
6642                     struct _mesa_glsl_parse_state *state)
6643 {
6644    ir_factory body(instructions, state);
6645 
6646    ir_variable *const fallthru_var = state->switch_state.is_fallthru_var;
6647 
6648    /* If not default case, ... */
6649    if (this->test_value != NULL) {
6650       /* Conditionally set fallthru state based on
6651        * comparison of cached test expression value to case label.
6652        */
6653       ir_rvalue *const label_rval = this->test_value->hir(instructions, state);
6654       ir_constant *label_const =
6655          label_rval->constant_expression_value(body.mem_ctx);
6656 
6657       if (!label_const) {
6658          YYLTYPE loc = this->test_value->get_location();
6659 
6660          _mesa_glsl_error(& loc, state,
6661                           "switch statement case label must be a "
6662                           "constant expression");
6663 
6664          /* Stuff a dummy value in to allow processing to continue. */
6665          label_const = body.constant(0);
6666       } else {
6667          hash_entry *entry =
6668                _mesa_hash_table_search(state->switch_state.labels_ht,
6669                                        &label_const->value.u[0]);
6670 
6671          if (entry) {
6672             const struct case_label *const l =
6673                (struct case_label *) entry->data;
6674             const ast_expression *const previous_label = l->ast;
6675             YYLTYPE loc = this->test_value->get_location();
6676 
6677             _mesa_glsl_error(& loc, state, "duplicate case value");
6678 
6679             loc = previous_label->get_location();
6680             _mesa_glsl_error(& loc, state, "this is the previous case label");
6681          } else {
6682             struct case_label *l = ralloc(state->switch_state.labels_ht,
6683                                           struct case_label);
6684 
6685             l->value = label_const->value.u[0];
6686             l->after_default = state->switch_state.previous_default != NULL;
6687             l->ast = this->test_value;
6688 
6689             _mesa_hash_table_insert(state->switch_state.labels_ht,
6690                                     &label_const->value.u[0],
6691                                     l);
6692          }
6693       }
6694 
6695       /* Create an r-value version of the ir_constant label here (after we may
6696        * have created a fake one in error cases) that can be passed to
6697        * apply_implicit_conversion below.
6698        */
6699       ir_rvalue *label = label_const;
6700 
6701       ir_rvalue *deref_test_var =
6702          new(body.mem_ctx) ir_dereference_variable(state->switch_state.test_var);
6703 
6704       /*
6705        * From GLSL 4.40 specification section 6.2 ("Selection"):
6706        *
6707        *     "The type of the init-expression value in a switch statement must
6708        *     be a scalar int or uint. The type of the constant-expression value
6709        *     in a case label also must be a scalar int or uint. When any pair
6710        *     of these values is tested for "equal value" and the types do not
6711        *     match, an implicit conversion will be done to convert the int to a
6712        *     uint (see section 4.1.10 “Implicit Conversions”) before the compare
6713        *     is done."
6714        */
6715       if (label->type != state->switch_state.test_var->type) {
6716          YYLTYPE loc = this->test_value->get_location();
6717 
6718          const glsl_type *type_a = label->type;
6719          const glsl_type *type_b = state->switch_state.test_var->type;
6720 
6721          /* Check if int->uint implicit conversion is supported. */
6722          bool integer_conversion_supported =
6723             glsl_type::int_type->can_implicitly_convert_to(glsl_type::uint_type,
6724                                                            state);
6725 
6726          if ((!type_a->is_integer() || !type_b->is_integer()) ||
6727               !integer_conversion_supported) {
6728             _mesa_glsl_error(&loc, state, "type mismatch with switch "
6729                              "init-expression and case label (%s != %s)",
6730                              type_a->name, type_b->name);
6731          } else {
6732             /* Conversion of the case label. */
6733             if (type_a->base_type == GLSL_TYPE_INT) {
6734                if (!apply_implicit_conversion(glsl_type::uint_type,
6735                                               label, state))
6736                   _mesa_glsl_error(&loc, state, "implicit type conversion error");
6737             } else {
6738                /* Conversion of the init-expression value. */
6739                if (!apply_implicit_conversion(glsl_type::uint_type,
6740                                               deref_test_var, state))
6741                   _mesa_glsl_error(&loc, state, "implicit type conversion error");
6742             }
6743          }
6744 
6745          /* If the implicit conversion was allowed, the types will already be
6746           * the same.  If the implicit conversion wasn't allowed, smash the
6747           * type of the label anyway.  This will prevent the expression
6748           * constructor (below) from failing an assertion.
6749           */
6750          label->type = deref_test_var->type;
6751       }
6752 
6753       body.emit(assign(fallthru_var,
6754                        logic_or(fallthru_var, equal(label, deref_test_var))));
6755    } else { /* default case */
6756       if (state->switch_state.previous_default) {
6757          YYLTYPE loc = this->get_location();
6758          _mesa_glsl_error(& loc, state,
6759                           "multiple default labels in one switch");
6760 
6761          loc = state->switch_state.previous_default->get_location();
6762          _mesa_glsl_error(& loc, state, "this is the first default label");
6763       }
6764       state->switch_state.previous_default = this;
6765 
6766       /* Set fallthru condition on 'run_default' bool. */
6767       body.emit(assign(fallthru_var,
6768                        logic_or(fallthru_var,
6769                                 state->switch_state.run_default)));
6770    }
6771 
6772    /* Case statements do not have r-values. */
6773    return NULL;
6774 }
6775 
6776 void
condition_to_hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6777 ast_iteration_statement::condition_to_hir(exec_list *instructions,
6778                                           struct _mesa_glsl_parse_state *state)
6779 {
6780    void *ctx = state;
6781 
6782    if (condition != NULL) {
6783       ir_rvalue *const cond =
6784          condition->hir(instructions, state);
6785 
6786       if ((cond == NULL)
6787           || !cond->type->is_boolean() || !cond->type->is_scalar()) {
6788          YYLTYPE loc = condition->get_location();
6789 
6790          _mesa_glsl_error(& loc, state,
6791                           "loop condition must be scalar boolean");
6792       } else {
6793          /* As the first code in the loop body, generate a block that looks
6794           * like 'if (!condition) break;' as the loop termination condition.
6795           */
6796          ir_rvalue *const not_cond =
6797             new(ctx) ir_expression(ir_unop_logic_not, cond);
6798 
6799          ir_if *const if_stmt = new(ctx) ir_if(not_cond);
6800 
6801          ir_jump *const break_stmt =
6802             new(ctx) ir_loop_jump(ir_loop_jump::jump_break);
6803 
6804          if_stmt->then_instructions.push_tail(break_stmt);
6805          instructions->push_tail(if_stmt);
6806       }
6807    }
6808 }
6809 
6810 
6811 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6812 ast_iteration_statement::hir(exec_list *instructions,
6813                              struct _mesa_glsl_parse_state *state)
6814 {
6815    void *ctx = state;
6816 
6817    /* For-loops and while-loops start a new scope, but do-while loops do not.
6818     */
6819    if (mode != ast_do_while)
6820       state->symbols->push_scope();
6821 
6822    if (init_statement != NULL)
6823       init_statement->hir(instructions, state);
6824 
6825    ir_loop *const stmt = new(ctx) ir_loop();
6826    instructions->push_tail(stmt);
6827 
6828    /* Track the current loop nesting. */
6829    ast_iteration_statement *nesting_ast = state->loop_nesting_ast;
6830 
6831    state->loop_nesting_ast = this;
6832 
6833    /* Likewise, indicate that following code is closest to a loop,
6834     * NOT closest to a switch.
6835     */
6836    bool saved_is_switch_innermost = state->switch_state.is_switch_innermost;
6837    state->switch_state.is_switch_innermost = false;
6838 
6839    if (mode != ast_do_while)
6840       condition_to_hir(&stmt->body_instructions, state);
6841 
6842    if (body != NULL)
6843       body->hir(& stmt->body_instructions, state);
6844 
6845    if (rest_expression != NULL)
6846       rest_expression->hir(& stmt->body_instructions, state);
6847 
6848    if (mode == ast_do_while)
6849       condition_to_hir(&stmt->body_instructions, state);
6850 
6851    if (mode != ast_do_while)
6852       state->symbols->pop_scope();
6853 
6854    /* Restore previous nesting before returning. */
6855    state->loop_nesting_ast = nesting_ast;
6856    state->switch_state.is_switch_innermost = saved_is_switch_innermost;
6857 
6858    /* Loops do not have r-values.
6859     */
6860    return NULL;
6861 }
6862 
6863 
6864 /**
6865  * Determine if the given type is valid for establishing a default precision
6866  * qualifier.
6867  *
6868  * From GLSL ES 3.00 section 4.5.4 ("Default Precision Qualifiers"):
6869  *
6870  *     "The precision statement
6871  *
6872  *         precision precision-qualifier type;
6873  *
6874  *     can be used to establish a default precision qualifier. The type field
6875  *     can be either int or float or any of the sampler types, and the
6876  *     precision-qualifier can be lowp, mediump, or highp."
6877  *
6878  * GLSL ES 1.00 has similar language.  GLSL 1.30 doesn't allow precision
6879  * qualifiers on sampler types, but this seems like an oversight (since the
6880  * intention of including these in GLSL 1.30 is to allow compatibility with ES
6881  * shaders).  So we allow int, float, and all sampler types regardless of GLSL
6882  * version.
6883  */
6884 static bool
is_valid_default_precision_type(const struct glsl_type * const type)6885 is_valid_default_precision_type(const struct glsl_type *const type)
6886 {
6887    if (type == NULL)
6888       return false;
6889 
6890    switch (type->base_type) {
6891    case GLSL_TYPE_INT:
6892    case GLSL_TYPE_FLOAT:
6893       /* "int" and "float" are valid, but vectors and matrices are not. */
6894       return type->vector_elements == 1 && type->matrix_columns == 1;
6895    case GLSL_TYPE_SAMPLER:
6896    case GLSL_TYPE_IMAGE:
6897    case GLSL_TYPE_ATOMIC_UINT:
6898       return true;
6899    default:
6900       return false;
6901    }
6902 }
6903 
6904 
6905 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)6906 ast_type_specifier::hir(exec_list *instructions,
6907                         struct _mesa_glsl_parse_state *state)
6908 {
6909    if (this->default_precision == ast_precision_none && this->structure == NULL)
6910       return NULL;
6911 
6912    YYLTYPE loc = this->get_location();
6913 
6914    /* If this is a precision statement, check that the type to which it is
6915     * applied is either float or int.
6916     *
6917     * From section 4.5.3 of the GLSL 1.30 spec:
6918     *    "The precision statement
6919     *       precision precision-qualifier type;
6920     *    can be used to establish a default precision qualifier. The type
6921     *    field can be either int or float [...].  Any other types or
6922     *    qualifiers will result in an error.
6923     */
6924    if (this->default_precision != ast_precision_none) {
6925       if (!state->check_precision_qualifiers_allowed(&loc))
6926          return NULL;
6927 
6928       if (this->structure != NULL) {
6929          _mesa_glsl_error(&loc, state,
6930                           "precision qualifiers do not apply to structures");
6931          return NULL;
6932       }
6933 
6934       if (this->array_specifier != NULL) {
6935          _mesa_glsl_error(&loc, state,
6936                           "default precision statements do not apply to "
6937                           "arrays");
6938          return NULL;
6939       }
6940 
6941       const struct glsl_type *const type =
6942          state->symbols->get_type(this->type_name);
6943       if (!is_valid_default_precision_type(type)) {
6944          _mesa_glsl_error(&loc, state,
6945                           "default precision statements apply only to "
6946                           "float, int, and opaque types");
6947          return NULL;
6948       }
6949 
6950       if (state->es_shader) {
6951          /* Section 4.5.3 (Default Precision Qualifiers) of the GLSL ES 1.00
6952           * spec says:
6953           *
6954           *     "Non-precision qualified declarations will use the precision
6955           *     qualifier specified in the most recent precision statement
6956           *     that is still in scope. The precision statement has the same
6957           *     scoping rules as variable declarations. If it is declared
6958           *     inside a compound statement, its effect stops at the end of
6959           *     the innermost statement it was declared in. Precision
6960           *     statements in nested scopes override precision statements in
6961           *     outer scopes. Multiple precision statements for the same basic
6962           *     type can appear inside the same scope, with later statements
6963           *     overriding earlier statements within that scope."
6964           *
6965           * Default precision specifications follow the same scope rules as
6966           * variables.  So, we can track the state of the default precision
6967           * qualifiers in the symbol table, and the rules will just work.  This
6968           * is a slight abuse of the symbol table, but it has the semantics
6969           * that we want.
6970           */
6971          state->symbols->add_default_precision_qualifier(this->type_name,
6972                                                          this->default_precision);
6973       }
6974 
6975       /* FINISHME: Translate precision statements into IR. */
6976       return NULL;
6977    }
6978 
6979    /* _mesa_ast_set_aggregate_type() sets the <structure> field so that
6980     * process_record_constructor() can do type-checking on C-style initializer
6981     * expressions of structs, but ast_struct_specifier should only be translated
6982     * to HIR if it is declaring the type of a structure.
6983     *
6984     * The ->is_declaration field is false for initializers of variables
6985     * declared separately from the struct's type definition.
6986     *
6987     *    struct S { ... };              (is_declaration = true)
6988     *    struct T { ... } t = { ... };  (is_declaration = true)
6989     *    S s = { ... };                 (is_declaration = false)
6990     */
6991    if (this->structure != NULL && this->structure->is_declaration)
6992       return this->structure->hir(instructions, state);
6993 
6994    return NULL;
6995 }
6996 
6997 
6998 /**
6999  * Process a structure or interface block tree into an array of structure fields
7000  *
7001  * After parsing, where there are some syntax differnces, structures and
7002  * interface blocks are almost identical.  They are similar enough that the
7003  * AST for each can be processed the same way into a set of
7004  * \c glsl_struct_field to describe the members.
7005  *
7006  * If we're processing an interface block, var_mode should be the type of the
7007  * interface block (ir_var_shader_in, ir_var_shader_out, ir_var_uniform or
7008  * ir_var_shader_storage).  If we're processing a structure, var_mode should be
7009  * ir_var_auto.
7010  *
7011  * \return
7012  * The number of fields processed.  A pointer to the array structure fields is
7013  * stored in \c *fields_ret.
7014  */
7015 static unsigned
ast_process_struct_or_iface_block_members(exec_list * instructions,struct _mesa_glsl_parse_state * state,exec_list * declarations,glsl_struct_field ** fields_ret,bool is_interface,enum glsl_matrix_layout matrix_layout,bool allow_reserved_names,ir_variable_mode var_mode,ast_type_qualifier * layout,unsigned block_stream,unsigned block_xfb_buffer,unsigned block_xfb_offset,unsigned expl_location,unsigned expl_align)7016 ast_process_struct_or_iface_block_members(exec_list *instructions,
7017                                           struct _mesa_glsl_parse_state *state,
7018                                           exec_list *declarations,
7019                                           glsl_struct_field **fields_ret,
7020                                           bool is_interface,
7021                                           enum glsl_matrix_layout matrix_layout,
7022                                           bool allow_reserved_names,
7023                                           ir_variable_mode var_mode,
7024                                           ast_type_qualifier *layout,
7025                                           unsigned block_stream,
7026                                           unsigned block_xfb_buffer,
7027                                           unsigned block_xfb_offset,
7028                                           unsigned expl_location,
7029                                           unsigned expl_align)
7030 {
7031    unsigned decl_count = 0;
7032    unsigned next_offset = 0;
7033 
7034    /* Make an initial pass over the list of fields to determine how
7035     * many there are.  Each element in this list is an ast_declarator_list.
7036     * This means that we actually need to count the number of elements in the
7037     * 'declarations' list in each of the elements.
7038     */
7039    foreach_list_typed (ast_declarator_list, decl_list, link, declarations) {
7040       decl_count += decl_list->declarations.length();
7041    }
7042 
7043    /* Allocate storage for the fields and process the field
7044     * declarations.  As the declarations are processed, try to also convert
7045     * the types to HIR.  This ensures that structure definitions embedded in
7046     * other structure definitions or in interface blocks are processed.
7047     */
7048    glsl_struct_field *const fields = rzalloc_array(state, glsl_struct_field,
7049                                                    decl_count);
7050 
7051    bool first_member = true;
7052    bool first_member_has_explicit_location = false;
7053 
7054    unsigned i = 0;
7055    foreach_list_typed (ast_declarator_list, decl_list, link, declarations) {
7056       const char *type_name;
7057       YYLTYPE loc = decl_list->get_location();
7058 
7059       decl_list->type->specifier->hir(instructions, state);
7060 
7061       /* Section 4.1.8 (Structures) of the GLSL 1.10 spec says:
7062        *
7063        *    "Anonymous structures are not supported; so embedded structures
7064        *    must have a declarator. A name given to an embedded struct is
7065        *    scoped at the same level as the struct it is embedded in."
7066        *
7067        * The same section of the  GLSL 1.20 spec says:
7068        *
7069        *    "Anonymous structures are not supported. Embedded structures are
7070        *    not supported."
7071        *
7072        * The GLSL ES 1.00 and 3.00 specs have similar langauge. So, we allow
7073        * embedded structures in 1.10 only.
7074        */
7075       if (state->language_version != 110 &&
7076           decl_list->type->specifier->structure != NULL)
7077          _mesa_glsl_error(&loc, state,
7078                           "embedded structure declarations are not allowed");
7079 
7080       const glsl_type *decl_type =
7081          decl_list->type->glsl_type(& type_name, state);
7082 
7083       const struct ast_type_qualifier *const qual =
7084          &decl_list->type->qualifier;
7085 
7086       /* From section 4.3.9 of the GLSL 4.40 spec:
7087        *
7088        *    "[In interface blocks] opaque types are not allowed."
7089        *
7090        * It should be impossible for decl_type to be NULL here.  Cases that
7091        * might naturally lead to decl_type being NULL, especially for the
7092        * is_interface case, will have resulted in compilation having
7093        * already halted due to a syntax error.
7094        */
7095       assert(decl_type);
7096 
7097       if (is_interface) {
7098          /* From section 4.3.7 of the ARB_bindless_texture spec:
7099           *
7100           *    "(remove the following bullet from the last list on p. 39,
7101           *     thereby permitting sampler types in interface blocks; image
7102           *     types are also permitted in blocks by this extension)"
7103           *
7104           *     * sampler types are not allowed
7105           */
7106          if (decl_type->contains_atomic() ||
7107              (!state->has_bindless() && decl_type->contains_opaque())) {
7108             _mesa_glsl_error(&loc, state, "uniform/buffer in non-default "
7109                              "interface block contains %s variable",
7110                              state->has_bindless() ? "atomic" : "opaque");
7111          }
7112       } else {
7113          if (decl_type->contains_atomic()) {
7114             /* From section 4.1.7.3 of the GLSL 4.40 spec:
7115              *
7116              *    "Members of structures cannot be declared as atomic counter
7117              *     types."
7118              */
7119             _mesa_glsl_error(&loc, state, "atomic counter in structure");
7120          }
7121 
7122          if (!state->has_bindless() && decl_type->contains_image()) {
7123             /* FINISHME: Same problem as with atomic counters.
7124              * FINISHME: Request clarification from Khronos and add
7125              * FINISHME: spec quotation here.
7126              */
7127             _mesa_glsl_error(&loc, state, "image in structure");
7128          }
7129       }
7130 
7131       if (qual->flags.q.explicit_binding) {
7132          _mesa_glsl_error(&loc, state,
7133                           "binding layout qualifier cannot be applied "
7134                           "to struct or interface block members");
7135       }
7136 
7137       if (is_interface) {
7138          if (!first_member) {
7139             if (!layout->flags.q.explicit_location &&
7140                 ((first_member_has_explicit_location &&
7141                   !qual->flags.q.explicit_location) ||
7142                  (!first_member_has_explicit_location &&
7143                   qual->flags.q.explicit_location))) {
7144                _mesa_glsl_error(&loc, state,
7145                                 "when block-level location layout qualifier "
7146                                 "is not supplied either all members must "
7147                                 "have a location layout qualifier or all "
7148                                 "members must not have a location layout "
7149                                 "qualifier");
7150             }
7151          } else {
7152             first_member = false;
7153             first_member_has_explicit_location =
7154                qual->flags.q.explicit_location;
7155          }
7156       }
7157 
7158       if (qual->flags.q.std140 ||
7159           qual->flags.q.std430 ||
7160           qual->flags.q.packed ||
7161           qual->flags.q.shared) {
7162          _mesa_glsl_error(&loc, state,
7163                           "uniform/shader storage block layout qualifiers "
7164                           "std140, std430, packed, and shared can only be "
7165                           "applied to uniform/shader storage blocks, not "
7166                           "members");
7167       }
7168 
7169       if (qual->flags.q.constant) {
7170          _mesa_glsl_error(&loc, state,
7171                           "const storage qualifier cannot be applied "
7172                           "to struct or interface block members");
7173       }
7174 
7175       validate_memory_qualifier_for_type(state, &loc, qual, decl_type);
7176       validate_image_format_qualifier_for_type(state, &loc, qual, decl_type);
7177 
7178       /* From Section 4.4.2.3 (Geometry Outputs) of the GLSL 4.50 spec:
7179        *
7180        *   "A block member may be declared with a stream identifier, but
7181        *   the specified stream must match the stream associated with the
7182        *   containing block."
7183        */
7184       if (qual->flags.q.explicit_stream) {
7185          unsigned qual_stream;
7186          if (process_qualifier_constant(state, &loc, "stream",
7187                                         qual->stream, &qual_stream) &&
7188              qual_stream != block_stream) {
7189             _mesa_glsl_error(&loc, state, "stream layout qualifier on "
7190                              "interface block member does not match "
7191                              "the interface block (%u vs %u)", qual_stream,
7192                              block_stream);
7193          }
7194       }
7195 
7196       int xfb_buffer;
7197       unsigned explicit_xfb_buffer = 0;
7198       if (qual->flags.q.explicit_xfb_buffer) {
7199          unsigned qual_xfb_buffer;
7200          if (process_qualifier_constant(state, &loc, "xfb_buffer",
7201                                         qual->xfb_buffer, &qual_xfb_buffer)) {
7202             explicit_xfb_buffer = 1;
7203             if (qual_xfb_buffer != block_xfb_buffer)
7204                _mesa_glsl_error(&loc, state, "xfb_buffer layout qualifier on "
7205                                 "interface block member does not match "
7206                                 "the interface block (%u vs %u)",
7207                                 qual_xfb_buffer, block_xfb_buffer);
7208          }
7209          xfb_buffer = (int) qual_xfb_buffer;
7210       } else {
7211          if (layout)
7212             explicit_xfb_buffer = layout->flags.q.explicit_xfb_buffer;
7213          xfb_buffer = (int) block_xfb_buffer;
7214       }
7215 
7216       int xfb_stride = -1;
7217       if (qual->flags.q.explicit_xfb_stride) {
7218          unsigned qual_xfb_stride;
7219          if (process_qualifier_constant(state, &loc, "xfb_stride",
7220                                         qual->xfb_stride, &qual_xfb_stride)) {
7221             xfb_stride = (int) qual_xfb_stride;
7222          }
7223       }
7224 
7225       if (qual->flags.q.uniform && qual->has_interpolation()) {
7226          _mesa_glsl_error(&loc, state,
7227                           "interpolation qualifiers cannot be used "
7228                           "with uniform interface blocks");
7229       }
7230 
7231       if ((qual->flags.q.uniform || !is_interface) &&
7232           qual->has_auxiliary_storage()) {
7233          _mesa_glsl_error(&loc, state,
7234                           "auxiliary storage qualifiers cannot be used "
7235                           "in uniform blocks or structures.");
7236       }
7237 
7238       if (qual->flags.q.row_major || qual->flags.q.column_major) {
7239          if (!qual->flags.q.uniform && !qual->flags.q.buffer) {
7240             _mesa_glsl_error(&loc, state,
7241                              "row_major and column_major can only be "
7242                              "applied to interface blocks");
7243          } else
7244             validate_matrix_layout_for_type(state, &loc, decl_type, NULL);
7245       }
7246 
7247       foreach_list_typed (ast_declaration, decl, link,
7248                           &decl_list->declarations) {
7249          YYLTYPE loc = decl->get_location();
7250 
7251          if (!allow_reserved_names)
7252             validate_identifier(decl->identifier, loc, state);
7253 
7254          const struct glsl_type *field_type =
7255             process_array_type(&loc, decl_type, decl->array_specifier, state);
7256          validate_array_dimensions(field_type, state, &loc);
7257          fields[i].type = field_type;
7258          fields[i].name = decl->identifier;
7259          fields[i].interpolation =
7260             interpret_interpolation_qualifier(qual, field_type,
7261                                               var_mode, state, &loc);
7262          fields[i].centroid = qual->flags.q.centroid ? 1 : 0;
7263          fields[i].sample = qual->flags.q.sample ? 1 : 0;
7264          fields[i].patch = qual->flags.q.patch ? 1 : 0;
7265          fields[i].precision = qual->precision;
7266          fields[i].offset = -1;
7267          fields[i].explicit_xfb_buffer = explicit_xfb_buffer;
7268          fields[i].xfb_buffer = xfb_buffer;
7269          fields[i].xfb_stride = xfb_stride;
7270 
7271          if (qual->flags.q.explicit_location) {
7272             unsigned qual_location;
7273             if (process_qualifier_constant(state, &loc, "location",
7274                                            qual->location, &qual_location)) {
7275                fields[i].location = qual_location +
7276                   (fields[i].patch ? VARYING_SLOT_PATCH0 : VARYING_SLOT_VAR0);
7277                expl_location = fields[i].location +
7278                   fields[i].type->count_attribute_slots(false);
7279             }
7280          } else {
7281             if (layout && layout->flags.q.explicit_location) {
7282                fields[i].location = expl_location;
7283                expl_location += fields[i].type->count_attribute_slots(false);
7284             } else {
7285                fields[i].location = -1;
7286             }
7287          }
7288 
7289          /* Offset can only be used with std430 and std140 layouts an initial
7290           * value of 0 is used for error detection.
7291           */
7292          unsigned align = 0;
7293          unsigned size = 0;
7294          if (layout) {
7295             bool row_major;
7296             if (qual->flags.q.row_major ||
7297                 matrix_layout == GLSL_MATRIX_LAYOUT_ROW_MAJOR) {
7298                row_major = true;
7299             } else {
7300                row_major = false;
7301             }
7302 
7303             if(layout->flags.q.std140) {
7304                align = field_type->std140_base_alignment(row_major);
7305                size = field_type->std140_size(row_major);
7306             } else if (layout->flags.q.std430) {
7307                align = field_type->std430_base_alignment(row_major);
7308                size = field_type->std430_size(row_major);
7309             }
7310          }
7311 
7312          if (qual->flags.q.explicit_offset) {
7313             unsigned qual_offset;
7314             if (process_qualifier_constant(state, &loc, "offset",
7315                                            qual->offset, &qual_offset)) {
7316                if (align != 0 && size != 0) {
7317                    if (next_offset > qual_offset)
7318                       _mesa_glsl_error(&loc, state, "layout qualifier "
7319                                        "offset overlaps previous member");
7320 
7321                   if (qual_offset % align) {
7322                      _mesa_glsl_error(&loc, state, "layout qualifier offset "
7323                                       "must be a multiple of the base "
7324                                       "alignment of %s", field_type->name);
7325                   }
7326                   fields[i].offset = qual_offset;
7327                   next_offset = glsl_align(qual_offset + size, align);
7328                } else {
7329                   _mesa_glsl_error(&loc, state, "offset can only be used "
7330                                    "with std430 and std140 layouts");
7331                }
7332             }
7333          }
7334 
7335          if (qual->flags.q.explicit_align || expl_align != 0) {
7336             unsigned offset = fields[i].offset != -1 ? fields[i].offset :
7337                next_offset;
7338             if (align == 0 || size == 0) {
7339                _mesa_glsl_error(&loc, state, "align can only be used with "
7340                                 "std430 and std140 layouts");
7341             } else if (qual->flags.q.explicit_align) {
7342                unsigned member_align;
7343                if (process_qualifier_constant(state, &loc, "align",
7344                                               qual->align, &member_align)) {
7345                   if (member_align == 0 ||
7346                       member_align & (member_align - 1)) {
7347                      _mesa_glsl_error(&loc, state, "align layout qualifier "
7348                                       "in not a power of 2");
7349                   } else {
7350                      fields[i].offset = glsl_align(offset, member_align);
7351                      next_offset = glsl_align(fields[i].offset + size, align);
7352                   }
7353                }
7354             } else {
7355                fields[i].offset = glsl_align(offset, expl_align);
7356                next_offset = glsl_align(fields[i].offset + size, align);
7357             }
7358          } else if (!qual->flags.q.explicit_offset) {
7359             if (align != 0 && size != 0)
7360                next_offset = glsl_align(next_offset + size, align);
7361          }
7362 
7363          /* From the ARB_enhanced_layouts spec:
7364           *
7365           *    "The given offset applies to the first component of the first
7366           *    member of the qualified entity.  Then, within the qualified
7367           *    entity, subsequent components are each assigned, in order, to
7368           *    the next available offset aligned to a multiple of that
7369           *    component's size.  Aggregate types are flattened down to the
7370           *    component level to get this sequence of components."
7371           */
7372          if (qual->flags.q.explicit_xfb_offset) {
7373             unsigned xfb_offset;
7374             if (process_qualifier_constant(state, &loc, "xfb_offset",
7375                                            qual->offset, &xfb_offset)) {
7376                fields[i].offset = xfb_offset;
7377                block_xfb_offset = fields[i].offset +
7378                   4 * field_type->component_slots();
7379             }
7380          } else {
7381             if (layout && layout->flags.q.explicit_xfb_offset) {
7382                unsigned align = field_type->is_64bit() ? 8 : 4;
7383                fields[i].offset = glsl_align(block_xfb_offset, align);
7384                block_xfb_offset += 4 * field_type->component_slots();
7385             }
7386          }
7387 
7388          /* Propogate row- / column-major information down the fields of the
7389           * structure or interface block.  Structures need this data because
7390           * the structure may contain a structure that contains ... a matrix
7391           * that need the proper layout.
7392           */
7393          if (is_interface && layout &&
7394              (layout->flags.q.uniform || layout->flags.q.buffer) &&
7395              (field_type->without_array()->is_matrix()
7396               || field_type->without_array()->is_record())) {
7397             /* If no layout is specified for the field, inherit the layout
7398              * from the block.
7399              */
7400             fields[i].matrix_layout = matrix_layout;
7401 
7402             if (qual->flags.q.row_major)
7403                fields[i].matrix_layout = GLSL_MATRIX_LAYOUT_ROW_MAJOR;
7404             else if (qual->flags.q.column_major)
7405                fields[i].matrix_layout = GLSL_MATRIX_LAYOUT_COLUMN_MAJOR;
7406 
7407             /* If we're processing an uniform or buffer block, the matrix
7408              * layout must be decided by this point.
7409              */
7410             assert(fields[i].matrix_layout == GLSL_MATRIX_LAYOUT_ROW_MAJOR
7411                    || fields[i].matrix_layout == GLSL_MATRIX_LAYOUT_COLUMN_MAJOR);
7412          }
7413 
7414          /* Memory qualifiers are allowed on buffer and image variables, while
7415           * the format qualifier is only accepted for images.
7416           */
7417          if (var_mode == ir_var_shader_storage ||
7418              field_type->without_array()->is_image()) {
7419             /* For readonly and writeonly qualifiers the field definition,
7420              * if set, overwrites the layout qualifier.
7421              */
7422             if (qual->flags.q.read_only || qual->flags.q.write_only) {
7423                fields[i].memory_read_only = qual->flags.q.read_only;
7424                fields[i].memory_write_only = qual->flags.q.write_only;
7425             } else {
7426                fields[i].memory_read_only =
7427                   layout ? layout->flags.q.read_only : 0;
7428                fields[i].memory_write_only =
7429                   layout ? layout->flags.q.write_only : 0;
7430             }
7431 
7432             /* For other qualifiers, we set the flag if either the layout
7433              * qualifier or the field qualifier are set
7434              */
7435             fields[i].memory_coherent = qual->flags.q.coherent ||
7436                                         (layout && layout->flags.q.coherent);
7437             fields[i].memory_volatile = qual->flags.q._volatile ||
7438                                         (layout && layout->flags.q._volatile);
7439             fields[i].memory_restrict = qual->flags.q.restrict_flag ||
7440                                         (layout && layout->flags.q.restrict_flag);
7441 
7442             if (field_type->without_array()->is_image()) {
7443                if (qual->flags.q.explicit_image_format) {
7444                   if (qual->image_base_type !=
7445                       field_type->without_array()->sampled_type) {
7446                      _mesa_glsl_error(&loc, state, "format qualifier doesn't "
7447                                       "match the base data type of the image");
7448                   }
7449 
7450                   fields[i].image_format = qual->image_format;
7451                } else {
7452                   if (!qual->flags.q.write_only) {
7453                      _mesa_glsl_error(&loc, state, "image not qualified with "
7454                                       "`writeonly' must have a format layout "
7455                                       "qualifier");
7456                   }
7457 
7458                   fields[i].image_format = GL_NONE;
7459                }
7460             }
7461          }
7462 
7463          i++;
7464       }
7465    }
7466 
7467    assert(i == decl_count);
7468 
7469    *fields_ret = fields;
7470    return decl_count;
7471 }
7472 
7473 
7474 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)7475 ast_struct_specifier::hir(exec_list *instructions,
7476                           struct _mesa_glsl_parse_state *state)
7477 {
7478    YYLTYPE loc = this->get_location();
7479 
7480    unsigned expl_location = 0;
7481    if (layout && layout->flags.q.explicit_location) {
7482       if (!process_qualifier_constant(state, &loc, "location",
7483                                       layout->location, &expl_location)) {
7484          return NULL;
7485       } else {
7486          expl_location = VARYING_SLOT_VAR0 + expl_location;
7487       }
7488    }
7489 
7490    glsl_struct_field *fields;
7491    unsigned decl_count =
7492       ast_process_struct_or_iface_block_members(instructions,
7493                                                 state,
7494                                                 &this->declarations,
7495                                                 &fields,
7496                                                 false,
7497                                                 GLSL_MATRIX_LAYOUT_INHERITED,
7498                                                 false /* allow_reserved_names */,
7499                                                 ir_var_auto,
7500                                                 layout,
7501                                                 0, /* for interface only */
7502                                                 0, /* for interface only */
7503                                                 0, /* for interface only */
7504                                                 expl_location,
7505                                                 0 /* for interface only */);
7506 
7507    validate_identifier(this->name, loc, state);
7508 
7509    type = glsl_type::get_record_instance(fields, decl_count, this->name);
7510 
7511    if (!type->is_anonymous() && !state->symbols->add_type(name, type)) {
7512       const glsl_type *match = state->symbols->get_type(name);
7513       /* allow struct matching for desktop GL - older UE4 does this */
7514       if (match != NULL && state->is_version(130, 0) && match->record_compare(type, false))
7515          _mesa_glsl_warning(& loc, state, "struct `%s' previously defined", name);
7516       else
7517          _mesa_glsl_error(& loc, state, "struct `%s' previously defined", name);
7518    } else {
7519       const glsl_type **s = reralloc(state, state->user_structures,
7520                                      const glsl_type *,
7521                                      state->num_user_structures + 1);
7522       if (s != NULL) {
7523          s[state->num_user_structures] = type;
7524          state->user_structures = s;
7525          state->num_user_structures++;
7526       }
7527    }
7528 
7529    /* Structure type definitions do not have r-values.
7530     */
7531    return NULL;
7532 }
7533 
7534 
7535 /**
7536  * Visitor class which detects whether a given interface block has been used.
7537  */
7538 class interface_block_usage_visitor : public ir_hierarchical_visitor
7539 {
7540 public:
interface_block_usage_visitor(ir_variable_mode mode,const glsl_type * block)7541    interface_block_usage_visitor(ir_variable_mode mode, const glsl_type *block)
7542       : mode(mode), block(block), found(false)
7543    {
7544    }
7545 
visit(ir_dereference_variable * ir)7546    virtual ir_visitor_status visit(ir_dereference_variable *ir)
7547    {
7548       if (ir->var->data.mode == mode && ir->var->get_interface_type() == block) {
7549          found = true;
7550          return visit_stop;
7551       }
7552       return visit_continue;
7553    }
7554 
usage_found() const7555    bool usage_found() const
7556    {
7557       return this->found;
7558    }
7559 
7560 private:
7561    ir_variable_mode mode;
7562    const glsl_type *block;
7563    bool found;
7564 };
7565 
7566 static bool
is_unsized_array_last_element(ir_variable * v)7567 is_unsized_array_last_element(ir_variable *v)
7568 {
7569    const glsl_type *interface_type = v->get_interface_type();
7570    int length = interface_type->length;
7571 
7572    assert(v->type->is_unsized_array());
7573 
7574    /* Check if it is the last element of the interface */
7575    if (strcmp(interface_type->fields.structure[length-1].name, v->name) == 0)
7576       return true;
7577    return false;
7578 }
7579 
7580 static void
apply_memory_qualifiers(ir_variable * var,glsl_struct_field field)7581 apply_memory_qualifiers(ir_variable *var, glsl_struct_field field)
7582 {
7583    var->data.memory_read_only = field.memory_read_only;
7584    var->data.memory_write_only = field.memory_write_only;
7585    var->data.memory_coherent = field.memory_coherent;
7586    var->data.memory_volatile = field.memory_volatile;
7587    var->data.memory_restrict = field.memory_restrict;
7588 }
7589 
7590 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)7591 ast_interface_block::hir(exec_list *instructions,
7592                          struct _mesa_glsl_parse_state *state)
7593 {
7594    YYLTYPE loc = this->get_location();
7595 
7596    /* Interface blocks must be declared at global scope */
7597    if (state->current_function != NULL) {
7598       _mesa_glsl_error(&loc, state,
7599                        "Interface block `%s' must be declared "
7600                        "at global scope",
7601                        this->block_name);
7602    }
7603 
7604    /* Validate qualifiers:
7605     *
7606     * - Layout Qualifiers as per the table in Section 4.4
7607     *   ("Layout Qualifiers") of the GLSL 4.50 spec.
7608     *
7609     * - Memory Qualifiers as per Section 4.10 ("Memory Qualifiers") of the
7610     *   GLSL 4.50 spec:
7611     *
7612     *     "Additionally, memory qualifiers may also be used in the declaration
7613     *      of shader storage blocks"
7614     *
7615     * Note the table in Section 4.4 says std430 is allowed on both uniform and
7616     * buffer blocks however Section 4.4.5 (Uniform and Shader Storage Block
7617     * Layout Qualifiers) of the GLSL 4.50 spec says:
7618     *
7619     *    "The std430 qualifier is supported only for shader storage blocks;
7620     *    using std430 on a uniform block will result in a compile-time error."
7621     */
7622    ast_type_qualifier allowed_blk_qualifiers;
7623    allowed_blk_qualifiers.flags.i = 0;
7624    if (this->layout.flags.q.buffer || this->layout.flags.q.uniform) {
7625       allowed_blk_qualifiers.flags.q.shared = 1;
7626       allowed_blk_qualifiers.flags.q.packed = 1;
7627       allowed_blk_qualifiers.flags.q.std140 = 1;
7628       allowed_blk_qualifiers.flags.q.row_major = 1;
7629       allowed_blk_qualifiers.flags.q.column_major = 1;
7630       allowed_blk_qualifiers.flags.q.explicit_align = 1;
7631       allowed_blk_qualifiers.flags.q.explicit_binding = 1;
7632       if (this->layout.flags.q.buffer) {
7633          allowed_blk_qualifiers.flags.q.buffer = 1;
7634          allowed_blk_qualifiers.flags.q.std430 = 1;
7635          allowed_blk_qualifiers.flags.q.coherent = 1;
7636          allowed_blk_qualifiers.flags.q._volatile = 1;
7637          allowed_blk_qualifiers.flags.q.restrict_flag = 1;
7638          allowed_blk_qualifiers.flags.q.read_only = 1;
7639          allowed_blk_qualifiers.flags.q.write_only = 1;
7640       } else {
7641          allowed_blk_qualifiers.flags.q.uniform = 1;
7642       }
7643    } else {
7644       /* Interface block */
7645       assert(this->layout.flags.q.in || this->layout.flags.q.out);
7646 
7647       allowed_blk_qualifiers.flags.q.explicit_location = 1;
7648       if (this->layout.flags.q.out) {
7649          allowed_blk_qualifiers.flags.q.out = 1;
7650          if (state->stage == MESA_SHADER_GEOMETRY ||
7651           state->stage == MESA_SHADER_TESS_CTRL ||
7652           state->stage == MESA_SHADER_TESS_EVAL ||
7653           state->stage == MESA_SHADER_VERTEX ) {
7654             allowed_blk_qualifiers.flags.q.explicit_xfb_offset = 1;
7655             allowed_blk_qualifiers.flags.q.explicit_xfb_buffer = 1;
7656             allowed_blk_qualifiers.flags.q.xfb_buffer = 1;
7657             allowed_blk_qualifiers.flags.q.explicit_xfb_stride = 1;
7658             allowed_blk_qualifiers.flags.q.xfb_stride = 1;
7659             if (state->stage == MESA_SHADER_GEOMETRY) {
7660                allowed_blk_qualifiers.flags.q.stream = 1;
7661                allowed_blk_qualifiers.flags.q.explicit_stream = 1;
7662             }
7663             if (state->stage == MESA_SHADER_TESS_CTRL) {
7664                allowed_blk_qualifiers.flags.q.patch = 1;
7665             }
7666          }
7667       } else {
7668          allowed_blk_qualifiers.flags.q.in = 1;
7669          if (state->stage == MESA_SHADER_TESS_EVAL) {
7670             allowed_blk_qualifiers.flags.q.patch = 1;
7671          }
7672       }
7673    }
7674 
7675    this->layout.validate_flags(&loc, state, allowed_blk_qualifiers,
7676                                "invalid qualifier for block",
7677                                this->block_name);
7678 
7679    enum glsl_interface_packing packing;
7680    if (this->layout.flags.q.std140) {
7681       packing = GLSL_INTERFACE_PACKING_STD140;
7682    } else if (this->layout.flags.q.packed) {
7683       packing = GLSL_INTERFACE_PACKING_PACKED;
7684    } else if (this->layout.flags.q.std430) {
7685       packing = GLSL_INTERFACE_PACKING_STD430;
7686    } else {
7687       /* The default layout is shared.
7688        */
7689       packing = GLSL_INTERFACE_PACKING_SHARED;
7690    }
7691 
7692    ir_variable_mode var_mode;
7693    const char *iface_type_name;
7694    if (this->layout.flags.q.in) {
7695       var_mode = ir_var_shader_in;
7696       iface_type_name = "in";
7697    } else if (this->layout.flags.q.out) {
7698       var_mode = ir_var_shader_out;
7699       iface_type_name = "out";
7700    } else if (this->layout.flags.q.uniform) {
7701       var_mode = ir_var_uniform;
7702       iface_type_name = "uniform";
7703    } else if (this->layout.flags.q.buffer) {
7704       var_mode = ir_var_shader_storage;
7705       iface_type_name = "buffer";
7706    } else {
7707       var_mode = ir_var_auto;
7708       iface_type_name = "UNKNOWN";
7709       assert(!"interface block layout qualifier not found!");
7710    }
7711 
7712    enum glsl_matrix_layout matrix_layout = GLSL_MATRIX_LAYOUT_INHERITED;
7713    if (this->layout.flags.q.row_major)
7714       matrix_layout = GLSL_MATRIX_LAYOUT_ROW_MAJOR;
7715    else if (this->layout.flags.q.column_major)
7716       matrix_layout = GLSL_MATRIX_LAYOUT_COLUMN_MAJOR;
7717 
7718    bool redeclaring_per_vertex = strcmp(this->block_name, "gl_PerVertex") == 0;
7719    exec_list declared_variables;
7720    glsl_struct_field *fields;
7721 
7722    /* For blocks that accept memory qualifiers (i.e. shader storage), verify
7723     * that we don't have incompatible qualifiers
7724     */
7725    if (this->layout.flags.q.read_only && this->layout.flags.q.write_only) {
7726       _mesa_glsl_error(&loc, state,
7727                        "Interface block sets both readonly and writeonly");
7728    }
7729 
7730    unsigned qual_stream;
7731    if (!process_qualifier_constant(state, &loc, "stream", this->layout.stream,
7732                                    &qual_stream) ||
7733        !validate_stream_qualifier(&loc, state, qual_stream)) {
7734       /* If the stream qualifier is invalid it doesn't make sense to continue
7735        * on and try to compare stream layouts on member variables against it
7736        * so just return early.
7737        */
7738       return NULL;
7739    }
7740 
7741    unsigned qual_xfb_buffer;
7742    if (!process_qualifier_constant(state, &loc, "xfb_buffer",
7743                                    layout.xfb_buffer, &qual_xfb_buffer) ||
7744        !validate_xfb_buffer_qualifier(&loc, state, qual_xfb_buffer)) {
7745       return NULL;
7746    }
7747 
7748    unsigned qual_xfb_offset;
7749    if (layout.flags.q.explicit_xfb_offset) {
7750       if (!process_qualifier_constant(state, &loc, "xfb_offset",
7751                                       layout.offset, &qual_xfb_offset)) {
7752          return NULL;
7753       }
7754    }
7755 
7756    unsigned qual_xfb_stride;
7757    if (layout.flags.q.explicit_xfb_stride) {
7758       if (!process_qualifier_constant(state, &loc, "xfb_stride",
7759                                       layout.xfb_stride, &qual_xfb_stride)) {
7760          return NULL;
7761       }
7762    }
7763 
7764    unsigned expl_location = 0;
7765    if (layout.flags.q.explicit_location) {
7766       if (!process_qualifier_constant(state, &loc, "location",
7767                                       layout.location, &expl_location)) {
7768          return NULL;
7769       } else {
7770          expl_location += this->layout.flags.q.patch ? VARYING_SLOT_PATCH0
7771                                                      : VARYING_SLOT_VAR0;
7772       }
7773    }
7774 
7775    unsigned expl_align = 0;
7776    if (layout.flags.q.explicit_align) {
7777       if (!process_qualifier_constant(state, &loc, "align",
7778                                       layout.align, &expl_align)) {
7779          return NULL;
7780       } else {
7781          if (expl_align == 0 || expl_align & (expl_align - 1)) {
7782             _mesa_glsl_error(&loc, state, "align layout qualifier is not a "
7783                              "power of 2.");
7784             return NULL;
7785          }
7786       }
7787    }
7788 
7789    unsigned int num_variables =
7790       ast_process_struct_or_iface_block_members(&declared_variables,
7791                                                 state,
7792                                                 &this->declarations,
7793                                                 &fields,
7794                                                 true,
7795                                                 matrix_layout,
7796                                                 redeclaring_per_vertex,
7797                                                 var_mode,
7798                                                 &this->layout,
7799                                                 qual_stream,
7800                                                 qual_xfb_buffer,
7801                                                 qual_xfb_offset,
7802                                                 expl_location,
7803                                                 expl_align);
7804 
7805    if (!redeclaring_per_vertex) {
7806       validate_identifier(this->block_name, loc, state);
7807 
7808       /* From section 4.3.9 ("Interface Blocks") of the GLSL 4.50 spec:
7809        *
7810        *     "Block names have no other use within a shader beyond interface
7811        *     matching; it is a compile-time error to use a block name at global
7812        *     scope for anything other than as a block name."
7813        */
7814       ir_variable *var = state->symbols->get_variable(this->block_name);
7815       if (var && !var->type->is_interface()) {
7816          _mesa_glsl_error(&loc, state, "Block name `%s' is "
7817                           "already used in the scope.",
7818                           this->block_name);
7819       }
7820    }
7821 
7822    const glsl_type *earlier_per_vertex = NULL;
7823    if (redeclaring_per_vertex) {
7824       /* Find the previous declaration of gl_PerVertex.  If we're redeclaring
7825        * the named interface block gl_in, we can find it by looking at the
7826        * previous declaration of gl_in.  Otherwise we can find it by looking
7827        * at the previous decalartion of any of the built-in outputs,
7828        * e.g. gl_Position.
7829        *
7830        * Also check that the instance name and array-ness of the redeclaration
7831        * are correct.
7832        */
7833       switch (var_mode) {
7834       case ir_var_shader_in:
7835          if (ir_variable *earlier_gl_in =
7836              state->symbols->get_variable("gl_in")) {
7837             earlier_per_vertex = earlier_gl_in->get_interface_type();
7838          } else {
7839             _mesa_glsl_error(&loc, state,
7840                              "redeclaration of gl_PerVertex input not allowed "
7841                              "in the %s shader",
7842                              _mesa_shader_stage_to_string(state->stage));
7843          }
7844          if (this->instance_name == NULL ||
7845              strcmp(this->instance_name, "gl_in") != 0 || this->array_specifier == NULL ||
7846              !this->array_specifier->is_single_dimension()) {
7847             _mesa_glsl_error(&loc, state,
7848                              "gl_PerVertex input must be redeclared as "
7849                              "gl_in[]");
7850          }
7851          break;
7852       case ir_var_shader_out:
7853          if (ir_variable *earlier_gl_Position =
7854              state->symbols->get_variable("gl_Position")) {
7855             earlier_per_vertex = earlier_gl_Position->get_interface_type();
7856          } else if (ir_variable *earlier_gl_out =
7857                state->symbols->get_variable("gl_out")) {
7858             earlier_per_vertex = earlier_gl_out->get_interface_type();
7859          } else {
7860             _mesa_glsl_error(&loc, state,
7861                              "redeclaration of gl_PerVertex output not "
7862                              "allowed in the %s shader",
7863                              _mesa_shader_stage_to_string(state->stage));
7864          }
7865          if (state->stage == MESA_SHADER_TESS_CTRL) {
7866             if (this->instance_name == NULL ||
7867                 strcmp(this->instance_name, "gl_out") != 0 || this->array_specifier == NULL) {
7868                _mesa_glsl_error(&loc, state,
7869                                 "gl_PerVertex output must be redeclared as "
7870                                 "gl_out[]");
7871             }
7872          } else {
7873             if (this->instance_name != NULL) {
7874                _mesa_glsl_error(&loc, state,
7875                                 "gl_PerVertex output may not be redeclared with "
7876                                 "an instance name");
7877             }
7878          }
7879          break;
7880       default:
7881          _mesa_glsl_error(&loc, state,
7882                           "gl_PerVertex must be declared as an input or an "
7883                           "output");
7884          break;
7885       }
7886 
7887       if (earlier_per_vertex == NULL) {
7888          /* An error has already been reported.  Bail out to avoid null
7889           * dereferences later in this function.
7890           */
7891          return NULL;
7892       }
7893 
7894       /* Copy locations from the old gl_PerVertex interface block. */
7895       for (unsigned i = 0; i < num_variables; i++) {
7896          int j = earlier_per_vertex->field_index(fields[i].name);
7897          if (j == -1) {
7898             _mesa_glsl_error(&loc, state,
7899                              "redeclaration of gl_PerVertex must be a subset "
7900                              "of the built-in members of gl_PerVertex");
7901          } else {
7902             fields[i].location =
7903                earlier_per_vertex->fields.structure[j].location;
7904             fields[i].offset =
7905                earlier_per_vertex->fields.structure[j].offset;
7906             fields[i].interpolation =
7907                earlier_per_vertex->fields.structure[j].interpolation;
7908             fields[i].centroid =
7909                earlier_per_vertex->fields.structure[j].centroid;
7910             fields[i].sample =
7911                earlier_per_vertex->fields.structure[j].sample;
7912             fields[i].patch =
7913                earlier_per_vertex->fields.structure[j].patch;
7914             fields[i].precision =
7915                earlier_per_vertex->fields.structure[j].precision;
7916             fields[i].explicit_xfb_buffer =
7917                earlier_per_vertex->fields.structure[j].explicit_xfb_buffer;
7918             fields[i].xfb_buffer =
7919                earlier_per_vertex->fields.structure[j].xfb_buffer;
7920             fields[i].xfb_stride =
7921                earlier_per_vertex->fields.structure[j].xfb_stride;
7922          }
7923       }
7924 
7925       /* From section 7.1 ("Built-in Language Variables") of the GLSL 4.10
7926        * spec:
7927        *
7928        *     If a built-in interface block is redeclared, it must appear in
7929        *     the shader before any use of any member included in the built-in
7930        *     declaration, or a compilation error will result.
7931        *
7932        * This appears to be a clarification to the behaviour established for
7933        * gl_PerVertex by GLSL 1.50, therefore we implement this behaviour
7934        * regardless of GLSL version.
7935        */
7936       interface_block_usage_visitor v(var_mode, earlier_per_vertex);
7937       v.run(instructions);
7938       if (v.usage_found()) {
7939          _mesa_glsl_error(&loc, state,
7940                           "redeclaration of a built-in interface block must "
7941                           "appear before any use of any member of the "
7942                           "interface block");
7943       }
7944    }
7945 
7946    const glsl_type *block_type =
7947       glsl_type::get_interface_instance(fields,
7948                                         num_variables,
7949                                         packing,
7950                                         matrix_layout ==
7951                                            GLSL_MATRIX_LAYOUT_ROW_MAJOR,
7952                                         this->block_name);
7953 
7954    unsigned component_size = block_type->contains_double() ? 8 : 4;
7955    int xfb_offset =
7956       layout.flags.q.explicit_xfb_offset ? (int) qual_xfb_offset : -1;
7957    validate_xfb_offset_qualifier(&loc, state, xfb_offset, block_type,
7958                                  component_size);
7959 
7960    if (!state->symbols->add_interface(block_type->name, block_type, var_mode)) {
7961       YYLTYPE loc = this->get_location();
7962       _mesa_glsl_error(&loc, state, "interface block `%s' with type `%s' "
7963                        "already taken in the current scope",
7964                        this->block_name, iface_type_name);
7965    }
7966 
7967    /* Since interface blocks cannot contain statements, it should be
7968     * impossible for the block to generate any instructions.
7969     */
7970    assert(declared_variables.is_empty());
7971 
7972    /* From section 4.3.4 (Inputs) of the GLSL 1.50 spec:
7973     *
7974     *     Geometry shader input variables get the per-vertex values written
7975     *     out by vertex shader output variables of the same names. Since a
7976     *     geometry shader operates on a set of vertices, each input varying
7977     *     variable (or input block, see interface blocks below) needs to be
7978     *     declared as an array.
7979     */
7980    if (state->stage == MESA_SHADER_GEOMETRY && this->array_specifier == NULL &&
7981        var_mode == ir_var_shader_in) {
7982       _mesa_glsl_error(&loc, state, "geometry shader inputs must be arrays");
7983    } else if ((state->stage == MESA_SHADER_TESS_CTRL ||
7984                state->stage == MESA_SHADER_TESS_EVAL) &&
7985               !this->layout.flags.q.patch &&
7986               this->array_specifier == NULL &&
7987               var_mode == ir_var_shader_in) {
7988       _mesa_glsl_error(&loc, state, "per-vertex tessellation shader inputs must be arrays");
7989    } else if (state->stage == MESA_SHADER_TESS_CTRL &&
7990               !this->layout.flags.q.patch &&
7991               this->array_specifier == NULL &&
7992               var_mode == ir_var_shader_out) {
7993       _mesa_glsl_error(&loc, state, "tessellation control shader outputs must be arrays");
7994    }
7995 
7996 
7997    /* Page 39 (page 45 of the PDF) of section 4.3.7 in the GLSL ES 3.00 spec
7998     * says:
7999     *
8000     *     "If an instance name (instance-name) is used, then it puts all the
8001     *     members inside a scope within its own name space, accessed with the
8002     *     field selector ( . ) operator (analogously to structures)."
8003     */
8004    if (this->instance_name) {
8005       if (redeclaring_per_vertex) {
8006          /* When a built-in in an unnamed interface block is redeclared,
8007           * get_variable_being_redeclared() calls
8008           * check_builtin_array_max_size() to make sure that built-in array
8009           * variables aren't redeclared to illegal sizes.  But we're looking
8010           * at a redeclaration of a named built-in interface block.  So we
8011           * have to manually call check_builtin_array_max_size() for all parts
8012           * of the interface that are arrays.
8013           */
8014          for (unsigned i = 0; i < num_variables; i++) {
8015             if (fields[i].type->is_array()) {
8016                const unsigned size = fields[i].type->array_size();
8017                check_builtin_array_max_size(fields[i].name, size, loc, state);
8018             }
8019          }
8020       } else {
8021          validate_identifier(this->instance_name, loc, state);
8022       }
8023 
8024       ir_variable *var;
8025 
8026       if (this->array_specifier != NULL) {
8027          const glsl_type *block_array_type =
8028             process_array_type(&loc, block_type, this->array_specifier, state);
8029 
8030          /* Section 4.3.7 (Interface Blocks) of the GLSL 1.50 spec says:
8031           *
8032           *     For uniform blocks declared an array, each individual array
8033           *     element corresponds to a separate buffer object backing one
8034           *     instance of the block. As the array size indicates the number
8035           *     of buffer objects needed, uniform block array declarations
8036           *     must specify an array size.
8037           *
8038           * And a few paragraphs later:
8039           *
8040           *     Geometry shader input blocks must be declared as arrays and
8041           *     follow the array declaration and linking rules for all
8042           *     geometry shader inputs. All other input and output block
8043           *     arrays must specify an array size.
8044           *
8045           * The same applies to tessellation shaders.
8046           *
8047           * The upshot of this is that the only circumstance where an
8048           * interface array size *doesn't* need to be specified is on a
8049           * geometry shader input, tessellation control shader input,
8050           * tessellation control shader output, and tessellation evaluation
8051           * shader input.
8052           */
8053          if (block_array_type->is_unsized_array()) {
8054             bool allow_inputs = state->stage == MESA_SHADER_GEOMETRY ||
8055                                 state->stage == MESA_SHADER_TESS_CTRL ||
8056                                 state->stage == MESA_SHADER_TESS_EVAL;
8057             bool allow_outputs = state->stage == MESA_SHADER_TESS_CTRL;
8058 
8059             if (this->layout.flags.q.in) {
8060                if (!allow_inputs)
8061                   _mesa_glsl_error(&loc, state,
8062                                    "unsized input block arrays not allowed in "
8063                                    "%s shader",
8064                                    _mesa_shader_stage_to_string(state->stage));
8065             } else if (this->layout.flags.q.out) {
8066                if (!allow_outputs)
8067                   _mesa_glsl_error(&loc, state,
8068                                    "unsized output block arrays not allowed in "
8069                                    "%s shader",
8070                                    _mesa_shader_stage_to_string(state->stage));
8071             } else {
8072                /* by elimination, this is a uniform block array */
8073                _mesa_glsl_error(&loc, state,
8074                                 "unsized uniform block arrays not allowed in "
8075                                 "%s shader",
8076                                 _mesa_shader_stage_to_string(state->stage));
8077             }
8078          }
8079 
8080          /* From section 4.3.9 (Interface Blocks) of the GLSL ES 3.10 spec:
8081           *
8082           *     * Arrays of arrays of blocks are not allowed
8083           */
8084          if (state->es_shader && block_array_type->is_array() &&
8085              block_array_type->fields.array->is_array()) {
8086             _mesa_glsl_error(&loc, state,
8087                              "arrays of arrays interface blocks are "
8088                              "not allowed");
8089          }
8090 
8091          var = new(state) ir_variable(block_array_type,
8092                                       this->instance_name,
8093                                       var_mode);
8094       } else {
8095          var = new(state) ir_variable(block_type,
8096                                       this->instance_name,
8097                                       var_mode);
8098       }
8099 
8100       var->data.matrix_layout = matrix_layout == GLSL_MATRIX_LAYOUT_INHERITED
8101          ? GLSL_MATRIX_LAYOUT_COLUMN_MAJOR : matrix_layout;
8102 
8103       if (var_mode == ir_var_shader_in || var_mode == ir_var_uniform)
8104          var->data.read_only = true;
8105 
8106       var->data.patch = this->layout.flags.q.patch;
8107 
8108       if (state->stage == MESA_SHADER_GEOMETRY && var_mode == ir_var_shader_in)
8109          handle_geometry_shader_input_decl(state, loc, var);
8110       else if ((state->stage == MESA_SHADER_TESS_CTRL ||
8111            state->stage == MESA_SHADER_TESS_EVAL) && var_mode == ir_var_shader_in)
8112          handle_tess_shader_input_decl(state, loc, var);
8113       else if (state->stage == MESA_SHADER_TESS_CTRL && var_mode == ir_var_shader_out)
8114          handle_tess_ctrl_shader_output_decl(state, loc, var);
8115 
8116       for (unsigned i = 0; i < num_variables; i++) {
8117          if (var->data.mode == ir_var_shader_storage)
8118             apply_memory_qualifiers(var, fields[i]);
8119       }
8120 
8121       if (ir_variable *earlier =
8122           state->symbols->get_variable(this->instance_name)) {
8123          if (!redeclaring_per_vertex) {
8124             _mesa_glsl_error(&loc, state, "`%s' redeclared",
8125                              this->instance_name);
8126          }
8127          earlier->data.how_declared = ir_var_declared_normally;
8128          earlier->type = var->type;
8129          earlier->reinit_interface_type(block_type);
8130          delete var;
8131       } else {
8132          if (this->layout.flags.q.explicit_binding) {
8133             apply_explicit_binding(state, &loc, var, var->type,
8134                                    &this->layout);
8135          }
8136 
8137          var->data.stream = qual_stream;
8138          if (layout.flags.q.explicit_location) {
8139             var->data.location = expl_location;
8140             var->data.explicit_location = true;
8141          }
8142 
8143          state->symbols->add_variable(var);
8144          instructions->push_tail(var);
8145       }
8146    } else {
8147       /* In order to have an array size, the block must also be declared with
8148        * an instance name.
8149        */
8150       assert(this->array_specifier == NULL);
8151 
8152       for (unsigned i = 0; i < num_variables; i++) {
8153          ir_variable *var =
8154             new(state) ir_variable(fields[i].type,
8155                                    ralloc_strdup(state, fields[i].name),
8156                                    var_mode);
8157          var->data.interpolation = fields[i].interpolation;
8158          var->data.centroid = fields[i].centroid;
8159          var->data.sample = fields[i].sample;
8160          var->data.patch = fields[i].patch;
8161          var->data.stream = qual_stream;
8162          var->data.location = fields[i].location;
8163 
8164          if (fields[i].location != -1)
8165             var->data.explicit_location = true;
8166 
8167          var->data.explicit_xfb_buffer = fields[i].explicit_xfb_buffer;
8168          var->data.xfb_buffer = fields[i].xfb_buffer;
8169 
8170          if (fields[i].offset != -1)
8171             var->data.explicit_xfb_offset = true;
8172          var->data.offset = fields[i].offset;
8173 
8174          var->init_interface_type(block_type);
8175 
8176          if (var_mode == ir_var_shader_in || var_mode == ir_var_uniform)
8177             var->data.read_only = true;
8178 
8179          /* Precision qualifiers do not have any meaning in Desktop GLSL */
8180          if (state->es_shader) {
8181             var->data.precision =
8182                select_gles_precision(fields[i].precision, fields[i].type,
8183                                      state, &loc);
8184          }
8185 
8186          if (fields[i].matrix_layout == GLSL_MATRIX_LAYOUT_INHERITED) {
8187             var->data.matrix_layout = matrix_layout == GLSL_MATRIX_LAYOUT_INHERITED
8188                ? GLSL_MATRIX_LAYOUT_COLUMN_MAJOR : matrix_layout;
8189          } else {
8190             var->data.matrix_layout = fields[i].matrix_layout;
8191          }
8192 
8193          if (var->data.mode == ir_var_shader_storage)
8194             apply_memory_qualifiers(var, fields[i]);
8195 
8196          /* Examine var name here since var may get deleted in the next call */
8197          bool var_is_gl_id = is_gl_identifier(var->name);
8198 
8199          if (redeclaring_per_vertex) {
8200             bool is_redeclaration;
8201             var =
8202                get_variable_being_redeclared(&var, loc, state,
8203                                              true /* allow_all_redeclarations */,
8204                                              &is_redeclaration);
8205             if (!var_is_gl_id || !is_redeclaration) {
8206                _mesa_glsl_error(&loc, state,
8207                                 "redeclaration of gl_PerVertex can only "
8208                                 "include built-in variables");
8209             } else if (var->data.how_declared == ir_var_declared_normally) {
8210                _mesa_glsl_error(&loc, state,
8211                                 "`%s' has already been redeclared",
8212                                 var->name);
8213             } else {
8214                var->data.how_declared = ir_var_declared_in_block;
8215                var->reinit_interface_type(block_type);
8216             }
8217             continue;
8218          }
8219 
8220          if (state->symbols->get_variable(var->name) != NULL)
8221             _mesa_glsl_error(&loc, state, "`%s' redeclared", var->name);
8222 
8223          /* Propagate the "binding" keyword into this UBO/SSBO's fields.
8224           * The UBO declaration itself doesn't get an ir_variable unless it
8225           * has an instance name.  This is ugly.
8226           */
8227          if (this->layout.flags.q.explicit_binding) {
8228             apply_explicit_binding(state, &loc, var,
8229                                    var->get_interface_type(), &this->layout);
8230          }
8231 
8232          if (var->type->is_unsized_array()) {
8233             if (var->is_in_shader_storage_block() &&
8234                 is_unsized_array_last_element(var)) {
8235                var->data.from_ssbo_unsized_array = true;
8236             } else {
8237                /* From GLSL ES 3.10 spec, section 4.1.9 "Arrays":
8238                 *
8239                 * "If an array is declared as the last member of a shader storage
8240                 * block and the size is not specified at compile-time, it is
8241                 * sized at run-time. In all other cases, arrays are sized only
8242                 * at compile-time."
8243                 *
8244                 * In desktop GLSL it is allowed to have unsized-arrays that are
8245                 * not last, as long as we can determine that they are implicitly
8246                 * sized.
8247                 */
8248                if (state->es_shader) {
8249                   _mesa_glsl_error(&loc, state, "unsized array `%s' "
8250                                    "definition: only last member of a shader "
8251                                    "storage block can be defined as unsized "
8252                                    "array", fields[i].name);
8253                }
8254             }
8255          }
8256 
8257          state->symbols->add_variable(var);
8258          instructions->push_tail(var);
8259       }
8260 
8261       if (redeclaring_per_vertex && block_type != earlier_per_vertex) {
8262          /* From section 7.1 ("Built-in Language Variables") of the GLSL 4.10 spec:
8263           *
8264           *     It is also a compilation error ... to redeclare a built-in
8265           *     block and then use a member from that built-in block that was
8266           *     not included in the redeclaration.
8267           *
8268           * This appears to be a clarification to the behaviour established
8269           * for gl_PerVertex by GLSL 1.50, therefore we implement this
8270           * behaviour regardless of GLSL version.
8271           *
8272           * To prevent the shader from using a member that was not included in
8273           * the redeclaration, we disable any ir_variables that are still
8274           * associated with the old declaration of gl_PerVertex (since we've
8275           * already updated all of the variables contained in the new
8276           * gl_PerVertex to point to it).
8277           *
8278           * As a side effect this will prevent
8279           * validate_intrastage_interface_blocks() from getting confused and
8280           * thinking there are conflicting definitions of gl_PerVertex in the
8281           * shader.
8282           */
8283          foreach_in_list_safe(ir_instruction, node, instructions) {
8284             ir_variable *const var = node->as_variable();
8285             if (var != NULL &&
8286                 var->get_interface_type() == earlier_per_vertex &&
8287                 var->data.mode == var_mode) {
8288                if (var->data.how_declared == ir_var_declared_normally) {
8289                   _mesa_glsl_error(&loc, state,
8290                                    "redeclaration of gl_PerVertex cannot "
8291                                    "follow a redeclaration of `%s'",
8292                                    var->name);
8293                }
8294                state->symbols->disable_variable(var->name);
8295                var->remove();
8296             }
8297          }
8298       }
8299    }
8300 
8301    return NULL;
8302 }
8303 
8304 
8305 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)8306 ast_tcs_output_layout::hir(exec_list *instructions,
8307                            struct _mesa_glsl_parse_state *state)
8308 {
8309    YYLTYPE loc = this->get_location();
8310 
8311    unsigned num_vertices;
8312    if (!state->out_qualifier->vertices->
8313           process_qualifier_constant(state, "vertices", &num_vertices,
8314                                      false)) {
8315       /* return here to stop cascading incorrect error messages */
8316      return NULL;
8317    }
8318 
8319    /* If any shader outputs occurred before this declaration and specified an
8320     * array size, make sure the size they specified is consistent with the
8321     * primitive type.
8322     */
8323    if (state->tcs_output_size != 0 && state->tcs_output_size != num_vertices) {
8324       _mesa_glsl_error(&loc, state,
8325                        "this tessellation control shader output layout "
8326                        "specifies %u vertices, but a previous output "
8327                        "is declared with size %u",
8328                        num_vertices, state->tcs_output_size);
8329       return NULL;
8330    }
8331 
8332    state->tcs_output_vertices_specified = true;
8333 
8334    /* If any shader outputs occurred before this declaration and did not
8335     * specify an array size, their size is determined now.
8336     */
8337    foreach_in_list (ir_instruction, node, instructions) {
8338       ir_variable *var = node->as_variable();
8339       if (var == NULL || var->data.mode != ir_var_shader_out)
8340          continue;
8341 
8342       /* Note: Not all tessellation control shader output are arrays. */
8343       if (!var->type->is_unsized_array() || var->data.patch)
8344          continue;
8345 
8346       if (var->data.max_array_access >= (int)num_vertices) {
8347          _mesa_glsl_error(&loc, state,
8348                           "this tessellation control shader output layout "
8349                           "specifies %u vertices, but an access to element "
8350                           "%u of output `%s' already exists", num_vertices,
8351                           var->data.max_array_access, var->name);
8352       } else {
8353          var->type = glsl_type::get_array_instance(var->type->fields.array,
8354                                                    num_vertices);
8355       }
8356    }
8357 
8358    return NULL;
8359 }
8360 
8361 
8362 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)8363 ast_gs_input_layout::hir(exec_list *instructions,
8364                          struct _mesa_glsl_parse_state *state)
8365 {
8366    YYLTYPE loc = this->get_location();
8367 
8368    /* Should have been prevented by the parser. */
8369    assert(!state->gs_input_prim_type_specified
8370           || state->in_qualifier->prim_type == this->prim_type);
8371 
8372    /* If any shader inputs occurred before this declaration and specified an
8373     * array size, make sure the size they specified is consistent with the
8374     * primitive type.
8375     */
8376    unsigned num_vertices = vertices_per_prim(this->prim_type);
8377    if (state->gs_input_size != 0 && state->gs_input_size != num_vertices) {
8378       _mesa_glsl_error(&loc, state,
8379                        "this geometry shader input layout implies %u vertices"
8380                        " per primitive, but a previous input is declared"
8381                        " with size %u", num_vertices, state->gs_input_size);
8382       return NULL;
8383    }
8384 
8385    state->gs_input_prim_type_specified = true;
8386 
8387    /* If any shader inputs occurred before this declaration and did not
8388     * specify an array size, their size is determined now.
8389     */
8390    foreach_in_list(ir_instruction, node, instructions) {
8391       ir_variable *var = node->as_variable();
8392       if (var == NULL || var->data.mode != ir_var_shader_in)
8393          continue;
8394 
8395       /* Note: gl_PrimitiveIDIn has mode ir_var_shader_in, but it's not an
8396        * array; skip it.
8397        */
8398 
8399       if (var->type->is_unsized_array()) {
8400          if (var->data.max_array_access >= (int)num_vertices) {
8401             _mesa_glsl_error(&loc, state,
8402                              "this geometry shader input layout implies %u"
8403                              " vertices, but an access to element %u of input"
8404                              " `%s' already exists", num_vertices,
8405                              var->data.max_array_access, var->name);
8406          } else {
8407             var->type = glsl_type::get_array_instance(var->type->fields.array,
8408                                                       num_vertices);
8409          }
8410       }
8411    }
8412 
8413    return NULL;
8414 }
8415 
8416 
8417 ir_rvalue *
hir(exec_list * instructions,struct _mesa_glsl_parse_state * state)8418 ast_cs_input_layout::hir(exec_list *instructions,
8419                          struct _mesa_glsl_parse_state *state)
8420 {
8421    YYLTYPE loc = this->get_location();
8422 
8423    /* From the ARB_compute_shader specification:
8424     *
8425     *     If the local size of the shader in any dimension is greater
8426     *     than the maximum size supported by the implementation for that
8427     *     dimension, a compile-time error results.
8428     *
8429     * It is not clear from the spec how the error should be reported if
8430     * the total size of the work group exceeds
8431     * MAX_COMPUTE_WORK_GROUP_INVOCATIONS, but it seems reasonable to
8432     * report it at compile time as well.
8433     */
8434    GLuint64 total_invocations = 1;
8435    unsigned qual_local_size[3];
8436    for (int i = 0; i < 3; i++) {
8437 
8438       char *local_size_str = ralloc_asprintf(NULL, "invalid local_size_%c",
8439                                              'x' + i);
8440       /* Infer a local_size of 1 for unspecified dimensions */
8441       if (this->local_size[i] == NULL) {
8442          qual_local_size[i] = 1;
8443       } else if (!this->local_size[i]->
8444              process_qualifier_constant(state, local_size_str,
8445                                         &qual_local_size[i], false)) {
8446          ralloc_free(local_size_str);
8447          return NULL;
8448       }
8449       ralloc_free(local_size_str);
8450 
8451       if (qual_local_size[i] > state->ctx->Const.MaxComputeWorkGroupSize[i]) {
8452          _mesa_glsl_error(&loc, state,
8453                           "local_size_%c exceeds MAX_COMPUTE_WORK_GROUP_SIZE"
8454                           " (%d)", 'x' + i,
8455                           state->ctx->Const.MaxComputeWorkGroupSize[i]);
8456          break;
8457       }
8458       total_invocations *= qual_local_size[i];
8459       if (total_invocations >
8460           state->ctx->Const.MaxComputeWorkGroupInvocations) {
8461          _mesa_glsl_error(&loc, state,
8462                           "product of local_sizes exceeds "
8463                           "MAX_COMPUTE_WORK_GROUP_INVOCATIONS (%d)",
8464                           state->ctx->Const.MaxComputeWorkGroupInvocations);
8465          break;
8466       }
8467    }
8468 
8469    /* If any compute input layout declaration preceded this one, make sure it
8470     * was consistent with this one.
8471     */
8472    if (state->cs_input_local_size_specified) {
8473       for (int i = 0; i < 3; i++) {
8474          if (state->cs_input_local_size[i] != qual_local_size[i]) {
8475             _mesa_glsl_error(&loc, state,
8476                              "compute shader input layout does not match"
8477                              " previous declaration");
8478             return NULL;
8479          }
8480       }
8481    }
8482 
8483    /* The ARB_compute_variable_group_size spec says:
8484     *
8485     *     If a compute shader including a *local_size_variable* qualifier also
8486     *     declares a fixed local group size using the *local_size_x*,
8487     *     *local_size_y*, or *local_size_z* qualifiers, a compile-time error
8488     *     results
8489     */
8490    if (state->cs_input_local_size_variable_specified) {
8491       _mesa_glsl_error(&loc, state,
8492                        "compute shader can't include both a variable and a "
8493                        "fixed local group size");
8494       return NULL;
8495    }
8496 
8497    state->cs_input_local_size_specified = true;
8498    for (int i = 0; i < 3; i++)
8499       state->cs_input_local_size[i] = qual_local_size[i];
8500 
8501    /* We may now declare the built-in constant gl_WorkGroupSize (see
8502     * builtin_variable_generator::generate_constants() for why we didn't
8503     * declare it earlier).
8504     */
8505    ir_variable *var = new(state->symbols)
8506       ir_variable(glsl_type::uvec3_type, "gl_WorkGroupSize", ir_var_auto);
8507    var->data.how_declared = ir_var_declared_implicitly;
8508    var->data.read_only = true;
8509    instructions->push_tail(var);
8510    state->symbols->add_variable(var);
8511    ir_constant_data data;
8512    memset(&data, 0, sizeof(data));
8513    for (int i = 0; i < 3; i++)
8514       data.u[i] = qual_local_size[i];
8515    var->constant_value = new(var) ir_constant(glsl_type::uvec3_type, &data);
8516    var->constant_initializer =
8517       new(var) ir_constant(glsl_type::uvec3_type, &data);
8518    var->data.has_initializer = true;
8519 
8520    return NULL;
8521 }
8522 
8523 
8524 static void
detect_conflicting_assignments(struct _mesa_glsl_parse_state * state,exec_list * instructions)8525 detect_conflicting_assignments(struct _mesa_glsl_parse_state *state,
8526                                exec_list *instructions)
8527 {
8528    bool gl_FragColor_assigned = false;
8529    bool gl_FragData_assigned = false;
8530    bool gl_FragSecondaryColor_assigned = false;
8531    bool gl_FragSecondaryData_assigned = false;
8532    bool user_defined_fs_output_assigned = false;
8533    ir_variable *user_defined_fs_output = NULL;
8534 
8535    /* It would be nice to have proper location information. */
8536    YYLTYPE loc;
8537    memset(&loc, 0, sizeof(loc));
8538 
8539    foreach_in_list(ir_instruction, node, instructions) {
8540       ir_variable *var = node->as_variable();
8541 
8542       if (!var || !var->data.assigned)
8543          continue;
8544 
8545       if (strcmp(var->name, "gl_FragColor") == 0)
8546          gl_FragColor_assigned = true;
8547       else if (strcmp(var->name, "gl_FragData") == 0)
8548          gl_FragData_assigned = true;
8549         else if (strcmp(var->name, "gl_SecondaryFragColorEXT") == 0)
8550          gl_FragSecondaryColor_assigned = true;
8551         else if (strcmp(var->name, "gl_SecondaryFragDataEXT") == 0)
8552          gl_FragSecondaryData_assigned = true;
8553       else if (!is_gl_identifier(var->name)) {
8554          if (state->stage == MESA_SHADER_FRAGMENT &&
8555              var->data.mode == ir_var_shader_out) {
8556             user_defined_fs_output_assigned = true;
8557             user_defined_fs_output = var;
8558          }
8559       }
8560    }
8561 
8562    /* From the GLSL 1.30 spec:
8563     *
8564     *     "If a shader statically assigns a value to gl_FragColor, it
8565     *      may not assign a value to any element of gl_FragData. If a
8566     *      shader statically writes a value to any element of
8567     *      gl_FragData, it may not assign a value to
8568     *      gl_FragColor. That is, a shader may assign values to either
8569     *      gl_FragColor or gl_FragData, but not both. Multiple shaders
8570     *      linked together must also consistently write just one of
8571     *      these variables.  Similarly, if user declared output
8572     *      variables are in use (statically assigned to), then the
8573     *      built-in variables gl_FragColor and gl_FragData may not be
8574     *      assigned to. These incorrect usages all generate compile
8575     *      time errors."
8576     */
8577    if (gl_FragColor_assigned && gl_FragData_assigned) {
8578       _mesa_glsl_error(&loc, state, "fragment shader writes to both "
8579                        "`gl_FragColor' and `gl_FragData'");
8580    } else if (gl_FragColor_assigned && user_defined_fs_output_assigned) {
8581       _mesa_glsl_error(&loc, state, "fragment shader writes to both "
8582                        "`gl_FragColor' and `%s'",
8583                        user_defined_fs_output->name);
8584    } else if (gl_FragSecondaryColor_assigned && gl_FragSecondaryData_assigned) {
8585       _mesa_glsl_error(&loc, state, "fragment shader writes to both "
8586                        "`gl_FragSecondaryColorEXT' and"
8587                        " `gl_FragSecondaryDataEXT'");
8588    } else if (gl_FragColor_assigned && gl_FragSecondaryData_assigned) {
8589       _mesa_glsl_error(&loc, state, "fragment shader writes to both "
8590                        "`gl_FragColor' and"
8591                        " `gl_FragSecondaryDataEXT'");
8592    } else if (gl_FragData_assigned && gl_FragSecondaryColor_assigned) {
8593       _mesa_glsl_error(&loc, state, "fragment shader writes to both "
8594                        "`gl_FragData' and"
8595                        " `gl_FragSecondaryColorEXT'");
8596    } else if (gl_FragData_assigned && user_defined_fs_output_assigned) {
8597       _mesa_glsl_error(&loc, state, "fragment shader writes to both "
8598                        "`gl_FragData' and `%s'",
8599                        user_defined_fs_output->name);
8600    }
8601 
8602    if ((gl_FragSecondaryColor_assigned || gl_FragSecondaryData_assigned) &&
8603        !state->EXT_blend_func_extended_enable) {
8604       _mesa_glsl_error(&loc, state,
8605                        "Dual source blending requires EXT_blend_func_extended");
8606    }
8607 }
8608 
8609 
8610 static void
remove_per_vertex_blocks(exec_list * instructions,_mesa_glsl_parse_state * state,ir_variable_mode mode)8611 remove_per_vertex_blocks(exec_list *instructions,
8612                          _mesa_glsl_parse_state *state, ir_variable_mode mode)
8613 {
8614    /* Find the gl_PerVertex interface block of the appropriate (in/out) mode,
8615     * if it exists in this shader type.
8616     */
8617    const glsl_type *per_vertex = NULL;
8618    switch (mode) {
8619    case ir_var_shader_in:
8620       if (ir_variable *gl_in = state->symbols->get_variable("gl_in"))
8621          per_vertex = gl_in->get_interface_type();
8622       break;
8623    case ir_var_shader_out:
8624       if (ir_variable *gl_Position =
8625           state->symbols->get_variable("gl_Position")) {
8626          per_vertex = gl_Position->get_interface_type();
8627       }
8628       break;
8629    default:
8630       assert(!"Unexpected mode");
8631       break;
8632    }
8633 
8634    /* If we didn't find a built-in gl_PerVertex interface block, then we don't
8635     * need to do anything.
8636     */
8637    if (per_vertex == NULL)
8638       return;
8639 
8640    /* If the interface block is used by the shader, then we don't need to do
8641     * anything.
8642     */
8643    interface_block_usage_visitor v(mode, per_vertex);
8644    v.run(instructions);
8645    if (v.usage_found())
8646       return;
8647 
8648    /* Remove any ir_variable declarations that refer to the interface block
8649     * we're removing.
8650     */
8651    foreach_in_list_safe(ir_instruction, node, instructions) {
8652       ir_variable *const var = node->as_variable();
8653       if (var != NULL && var->get_interface_type() == per_vertex &&
8654           var->data.mode == mode) {
8655          state->symbols->disable_variable(var->name);
8656          var->remove();
8657       }
8658    }
8659 }
8660