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1 /*
2  * Copyright (C) 2018-2019 Alyssa Rosenzweig <alyssa@rosenzweig.io>
3  * Copyright (C) 2019-2020 Collabora, Ltd.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22  * SOFTWARE.
23  */
24 
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 #include <sys/mman.h>
28 #include <fcntl.h>
29 #include <stdint.h>
30 #include <stdlib.h>
31 #include <stdio.h>
32 #include <err.h>
33 
34 #include "main/mtypes.h"
35 #include "compiler/glsl/glsl_to_nir.h"
36 #include "compiler/nir_types.h"
37 #include "compiler/nir/nir_builder.h"
38 #include "util/half_float.h"
39 #include "util/u_math.h"
40 #include "util/u_debug.h"
41 #include "util/u_dynarray.h"
42 #include "util/list.h"
43 #include "main/mtypes.h"
44 
45 #include "midgard.h"
46 #include "midgard_nir.h"
47 #include "midgard_compile.h"
48 #include "midgard_ops.h"
49 #include "helpers.h"
50 #include "compiler.h"
51 #include "midgard_quirks.h"
52 #include "panfrost-quirks.h"
53 #include "panfrost/util/pan_lower_framebuffer.h"
54 
55 #include "disassemble.h"
56 
57 static const struct debug_named_value debug_options[] = {
58         {"msgs",      MIDGARD_DBG_MSGS,		"Print debug messages"},
59         {"shaders",   MIDGARD_DBG_SHADERS,	"Dump shaders in NIR and MIR"},
60         {"shaderdb",  MIDGARD_DBG_SHADERDB,     "Prints shader-db statistics"},
61         DEBUG_NAMED_VALUE_END
62 };
63 
64 DEBUG_GET_ONCE_FLAGS_OPTION(midgard_debug, "MIDGARD_MESA_DEBUG", debug_options, 0)
65 
66 unsigned SHADER_DB_COUNT = 0;
67 
68 int midgard_debug = 0;
69 
70 #define DBG(fmt, ...) \
71 		do { if (midgard_debug & MIDGARD_DBG_MSGS) \
72 			fprintf(stderr, "%s:%d: "fmt, \
73 				__FUNCTION__, __LINE__, ##__VA_ARGS__); } while (0)
74 static midgard_block *
create_empty_block(compiler_context * ctx)75 create_empty_block(compiler_context *ctx)
76 {
77         midgard_block *blk = rzalloc(ctx, midgard_block);
78 
79         blk->base.predecessors = _mesa_set_create(blk,
80                         _mesa_hash_pointer,
81                         _mesa_key_pointer_equal);
82 
83         blk->base.name = ctx->block_source_count++;
84 
85         return blk;
86 }
87 
88 static void
schedule_barrier(compiler_context * ctx)89 schedule_barrier(compiler_context *ctx)
90 {
91         midgard_block *temp = ctx->after_block;
92         ctx->after_block = create_empty_block(ctx);
93         ctx->block_count++;
94         list_addtail(&ctx->after_block->base.link, &ctx->blocks);
95         list_inithead(&ctx->after_block->base.instructions);
96         pan_block_add_successor(&ctx->current_block->base, &ctx->after_block->base);
97         ctx->current_block = ctx->after_block;
98         ctx->after_block = temp;
99 }
100 
101 /* Helpers to generate midgard_instruction's using macro magic, since every
102  * driver seems to do it that way */
103 
104 #define EMIT(op, ...) emit_mir_instruction(ctx, v_##op(__VA_ARGS__));
105 
106 #define M_LOAD_STORE(name, store, T) \
107 	static midgard_instruction m_##name(unsigned ssa, unsigned address) { \
108 		midgard_instruction i = { \
109 			.type = TAG_LOAD_STORE_4, \
110                         .mask = 0xF, \
111                         .dest = ~0, \
112                         .src = { ~0, ~0, ~0, ~0 }, \
113                         .swizzle = SWIZZLE_IDENTITY_4, \
114                         .op = midgard_op_##name, \
115 			.load_store = { \
116 				.address = address \
117 			} \
118 		}; \
119                 \
120                 if (store) { \
121                         i.src[0] = ssa; \
122                         i.src_types[0] = T; \
123                         i.dest_type = T; \
124                 } else { \
125                         i.dest = ssa; \
126                         i.dest_type = T; \
127                 } \
128 		return i; \
129 	}
130 
131 #define M_LOAD(name, T) M_LOAD_STORE(name, false, T)
132 #define M_STORE(name, T) M_LOAD_STORE(name, true, T)
133 
134 M_LOAD(ld_attr_32, nir_type_uint32);
135 M_LOAD(ld_vary_32, nir_type_uint32);
136 M_LOAD(ld_ubo_int4, nir_type_uint32);
137 M_LOAD(ld_int4, nir_type_uint32);
138 M_STORE(st_int4, nir_type_uint32);
139 M_LOAD(ld_color_buffer_32u, nir_type_uint32);
140 M_LOAD(ld_color_buffer_as_fp16, nir_type_float16);
141 M_LOAD(ld_color_buffer_as_fp32, nir_type_float32);
142 M_STORE(st_vary_32, nir_type_uint32);
143 M_LOAD(ld_cubemap_coords, nir_type_uint32);
144 M_LOAD(ld_compute_id, nir_type_uint32);
145 
146 static midgard_instruction
v_branch(bool conditional,bool invert)147 v_branch(bool conditional, bool invert)
148 {
149         midgard_instruction ins = {
150                 .type = TAG_ALU_4,
151                 .unit = ALU_ENAB_BRANCH,
152                 .compact_branch = true,
153                 .branch = {
154                         .conditional = conditional,
155                         .invert_conditional = invert
156                 },
157                 .dest = ~0,
158                 .src = { ~0, ~0, ~0, ~0 },
159         };
160 
161         return ins;
162 }
163 
164 static void
attach_constants(compiler_context * ctx,midgard_instruction * ins,void * constants,int name)165 attach_constants(compiler_context *ctx, midgard_instruction *ins, void *constants, int name)
166 {
167         ins->has_constants = true;
168         memcpy(&ins->constants, constants, 16);
169 }
170 
171 static int
glsl_type_size(const struct glsl_type * type,bool bindless)172 glsl_type_size(const struct glsl_type *type, bool bindless)
173 {
174         return glsl_count_attribute_slots(type, false);
175 }
176 
177 /* Lower fdot2 to a vector multiplication followed by channel addition  */
178 static bool
midgard_nir_lower_fdot2_instr(nir_builder * b,nir_instr * instr,void * data)179 midgard_nir_lower_fdot2_instr(nir_builder *b, nir_instr *instr, void *data)
180 {
181         if (instr->type != nir_instr_type_alu)
182                 return false;
183 
184         nir_alu_instr *alu = nir_instr_as_alu(instr);
185         if (alu->op != nir_op_fdot2)
186                 return false;
187 
188         b->cursor = nir_before_instr(&alu->instr);
189 
190         nir_ssa_def *src0 = nir_ssa_for_alu_src(b, alu, 0);
191         nir_ssa_def *src1 = nir_ssa_for_alu_src(b, alu, 1);
192 
193         nir_ssa_def *product = nir_fmul(b, src0, src1);
194 
195         nir_ssa_def *sum = nir_fadd(b,
196                                     nir_channel(b, product, 0),
197                                     nir_channel(b, product, 1));
198 
199         /* Replace the fdot2 with this sum */
200         nir_ssa_def_rewrite_uses(&alu->dest.dest.ssa, nir_src_for_ssa(sum));
201 
202         return true;
203 }
204 
205 static bool
midgard_nir_lower_fdot2(nir_shader * shader)206 midgard_nir_lower_fdot2(nir_shader *shader)
207 {
208         return nir_shader_instructions_pass(shader,
209                                             midgard_nir_lower_fdot2_instr,
210                                             nir_metadata_block_index | nir_metadata_dominance,
211                                             NULL);
212 }
213 
214 static bool
mdg_is_64(const nir_instr * instr,const void * _unused)215 mdg_is_64(const nir_instr *instr, const void *_unused)
216 {
217         const nir_alu_instr *alu = nir_instr_as_alu(instr);
218 
219         if (nir_dest_bit_size(alu->dest.dest) == 64)
220                 return true;
221 
222         switch (alu->op) {
223         case nir_op_umul_high:
224         case nir_op_imul_high:
225                 return true;
226         default:
227                 return false;
228         }
229 }
230 
231 /* Flushes undefined values to zero */
232 
233 static void
optimise_nir(nir_shader * nir,unsigned quirks,bool is_blend)234 optimise_nir(nir_shader *nir, unsigned quirks, bool is_blend)
235 {
236         bool progress;
237         unsigned lower_flrp =
238                 (nir->options->lower_flrp16 ? 16 : 0) |
239                 (nir->options->lower_flrp32 ? 32 : 0) |
240                 (nir->options->lower_flrp64 ? 64 : 0);
241 
242         NIR_PASS(progress, nir, nir_lower_regs_to_ssa);
243         NIR_PASS(progress, nir, nir_lower_idiv, nir_lower_idiv_fast);
244 
245         nir_lower_tex_options lower_tex_options = {
246                 .lower_txs_lod = true,
247                 .lower_txp = ~0,
248                 .lower_tex_without_implicit_lod =
249                         (quirks & MIDGARD_EXPLICIT_LOD),
250                 .lower_tg4_broadcom_swizzle = true,
251 
252                 /* TODO: we have native gradient.. */
253                 .lower_txd = true,
254         };
255 
256         NIR_PASS(progress, nir, nir_lower_tex, &lower_tex_options);
257 
258         /* Must lower fdot2 after tex is lowered */
259         NIR_PASS(progress, nir, midgard_nir_lower_fdot2);
260 
261         /* T720 is broken. */
262 
263         if (quirks & MIDGARD_BROKEN_LOD)
264                 NIR_PASS_V(nir, midgard_nir_lod_errata);
265 
266         NIR_PASS(progress, nir, midgard_nir_lower_algebraic_early);
267 
268         do {
269                 progress = false;
270 
271                 NIR_PASS(progress, nir, nir_lower_var_copies);
272                 NIR_PASS(progress, nir, nir_lower_vars_to_ssa);
273 
274                 NIR_PASS(progress, nir, nir_copy_prop);
275                 NIR_PASS(progress, nir, nir_opt_remove_phis);
276                 NIR_PASS(progress, nir, nir_opt_dce);
277                 NIR_PASS(progress, nir, nir_opt_dead_cf);
278                 NIR_PASS(progress, nir, nir_opt_cse);
279                 NIR_PASS(progress, nir, nir_opt_peephole_select, 64, false, true);
280                 NIR_PASS(progress, nir, nir_opt_algebraic);
281                 NIR_PASS(progress, nir, nir_opt_constant_folding);
282 
283                 if (lower_flrp != 0) {
284                         bool lower_flrp_progress = false;
285                         NIR_PASS(lower_flrp_progress,
286                                  nir,
287                                  nir_lower_flrp,
288                                  lower_flrp,
289                                  false /* always_precise */);
290                         if (lower_flrp_progress) {
291                                 NIR_PASS(progress, nir,
292                                          nir_opt_constant_folding);
293                                 progress = true;
294                         }
295 
296                         /* Nothing should rematerialize any flrps, so we only
297                          * need to do this lowering once.
298                          */
299                         lower_flrp = 0;
300                 }
301 
302                 NIR_PASS(progress, nir, nir_opt_undef);
303                 NIR_PASS(progress, nir, nir_undef_to_zero);
304 
305                 NIR_PASS(progress, nir, nir_opt_loop_unroll,
306                          nir_var_shader_in |
307                          nir_var_shader_out |
308                          nir_var_function_temp);
309 
310                 NIR_PASS(progress, nir, nir_opt_vectorize, NULL, NULL);
311         } while (progress);
312 
313         NIR_PASS_V(nir, nir_lower_alu_to_scalar, mdg_is_64, NULL);
314 
315         /* Run after opts so it can hit more */
316         if (!is_blend)
317                 NIR_PASS(progress, nir, nir_fuse_io_16);
318 
319         /* Must be run at the end to prevent creation of fsin/fcos ops */
320         NIR_PASS(progress, nir, midgard_nir_scale_trig);
321 
322         do {
323                 progress = false;
324 
325                 NIR_PASS(progress, nir, nir_opt_dce);
326                 NIR_PASS(progress, nir, nir_opt_algebraic);
327                 NIR_PASS(progress, nir, nir_opt_constant_folding);
328                 NIR_PASS(progress, nir, nir_copy_prop);
329         } while (progress);
330 
331         NIR_PASS(progress, nir, nir_opt_algebraic_late);
332         NIR_PASS(progress, nir, nir_opt_algebraic_distribute_src_mods);
333 
334         /* We implement booleans as 32-bit 0/~0 */
335         NIR_PASS(progress, nir, nir_lower_bool_to_int32);
336 
337         /* Now that booleans are lowered, we can run out late opts */
338         NIR_PASS(progress, nir, midgard_nir_lower_algebraic_late);
339         NIR_PASS(progress, nir, midgard_nir_cancel_inot);
340 
341         NIR_PASS(progress, nir, nir_copy_prop);
342         NIR_PASS(progress, nir, nir_opt_dce);
343 
344         /* Take us out of SSA */
345         NIR_PASS(progress, nir, nir_lower_locals_to_regs);
346         NIR_PASS(progress, nir, nir_convert_from_ssa, true);
347 
348         /* We are a vector architecture; write combine where possible */
349         NIR_PASS(progress, nir, nir_move_vec_src_uses_to_dest);
350         NIR_PASS(progress, nir, nir_lower_vec_to_movs);
351 
352         NIR_PASS(progress, nir, nir_opt_dce);
353 }
354 
355 /* Do not actually emit a load; instead, cache the constant for inlining */
356 
357 static void
emit_load_const(compiler_context * ctx,nir_load_const_instr * instr)358 emit_load_const(compiler_context *ctx, nir_load_const_instr *instr)
359 {
360         nir_ssa_def def = instr->def;
361 
362         midgard_constants *consts = rzalloc(NULL, midgard_constants);
363 
364         assert(instr->def.num_components * instr->def.bit_size <= sizeof(*consts) * 8);
365 
366 #define RAW_CONST_COPY(bits)                                         \
367         nir_const_value_to_array(consts->u##bits, instr->value,      \
368                                  instr->def.num_components, u##bits)
369 
370         switch (instr->def.bit_size) {
371         case 64:
372                 RAW_CONST_COPY(64);
373                 break;
374         case 32:
375                 RAW_CONST_COPY(32);
376                 break;
377         case 16:
378                 RAW_CONST_COPY(16);
379                 break;
380         case 8:
381                 RAW_CONST_COPY(8);
382                 break;
383         default:
384                 unreachable("Invalid bit_size for load_const instruction\n");
385         }
386 
387         /* Shifted for SSA, +1 for off-by-one */
388         _mesa_hash_table_u64_insert(ctx->ssa_constants, (def.index << 1) + 1, consts);
389 }
390 
391 /* Normally constants are embedded implicitly, but for I/O and such we have to
392  * explicitly emit a move with the constant source */
393 
394 static void
emit_explicit_constant(compiler_context * ctx,unsigned node,unsigned to)395 emit_explicit_constant(compiler_context *ctx, unsigned node, unsigned to)
396 {
397         void *constant_value = _mesa_hash_table_u64_search(ctx->ssa_constants, node + 1);
398 
399         if (constant_value) {
400                 midgard_instruction ins = v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT), to);
401                 attach_constants(ctx, &ins, constant_value, node + 1);
402                 emit_mir_instruction(ctx, ins);
403         }
404 }
405 
406 static bool
nir_is_non_scalar_swizzle(nir_alu_src * src,unsigned nr_components)407 nir_is_non_scalar_swizzle(nir_alu_src *src, unsigned nr_components)
408 {
409         unsigned comp = src->swizzle[0];
410 
411         for (unsigned c = 1; c < nr_components; ++c) {
412                 if (src->swizzle[c] != comp)
413                         return true;
414         }
415 
416         return false;
417 }
418 
419 #define ATOMIC_CASE_IMPL(ctx, instr, nir, op, is_shared) \
420         case nir_intrinsic_##nir: \
421                 emit_atomic(ctx, instr, is_shared, midgard_op_##op); \
422                 break;
423 
424 #define ATOMIC_CASE(ctx, instr, nir, op) \
425         ATOMIC_CASE_IMPL(ctx, instr, shared_atomic_##nir, atomic_##op, true); \
426         ATOMIC_CASE_IMPL(ctx, instr, global_atomic_##nir, atomic_##op, false);
427 
428 #define ALU_CASE(nir, _op) \
429 	case nir_op_##nir: \
430 		op = midgard_alu_op_##_op; \
431                 assert(src_bitsize == dst_bitsize); \
432 		break;
433 
434 #define ALU_CASE_RTZ(nir, _op) \
435 	case nir_op_##nir: \
436 		op = midgard_alu_op_##_op; \
437                 roundmode = MIDGARD_RTZ; \
438 		break;
439 
440 #define ALU_CHECK_CMP() \
441                 assert(src_bitsize == 16 || src_bitsize == 32); \
442                 assert(dst_bitsize == 16 || dst_bitsize == 32); \
443 
444 #define ALU_CASE_BCAST(nir, _op, count) \
445         case nir_op_##nir: \
446                 op = midgard_alu_op_##_op; \
447                 broadcast_swizzle = count; \
448                 ALU_CHECK_CMP(); \
449                 break;
450 
451 #define ALU_CASE_CMP(nir, _op) \
452 	case nir_op_##nir: \
453 		op = midgard_alu_op_##_op; \
454                 ALU_CHECK_CMP(); \
455                 break;
456 
457 /* Compare mir_lower_invert */
458 static bool
nir_accepts_inot(nir_op op,unsigned src)459 nir_accepts_inot(nir_op op, unsigned src)
460 {
461         switch (op) {
462         case nir_op_ior:
463         case nir_op_iand: /* TODO: b2f16 */
464         case nir_op_ixor:
465                 return true;
466         case nir_op_b32csel:
467                 /* Only the condition */
468                 return (src == 0);
469         default:
470                 return false;
471         }
472 }
473 
474 static bool
mir_accept_dest_mod(compiler_context * ctx,nir_dest ** dest,nir_op op)475 mir_accept_dest_mod(compiler_context *ctx, nir_dest **dest, nir_op op)
476 {
477         if (pan_has_dest_mod(dest, op)) {
478                 assert((*dest)->is_ssa);
479                 BITSET_SET(ctx->already_emitted, (*dest)->ssa.index);
480                 return true;
481         }
482 
483         return false;
484 }
485 
486 /* Look for floating point mods. We have the mods fsat, fsat_signed,
487  * and fpos. We also have the relations (note 3 * 2 = 6 cases):
488  *
489  * fsat_signed(fpos(x)) = fsat(x)
490  * fsat_signed(fsat(x)) = fsat(x)
491  * fpos(fsat_signed(x)) = fsat(x)
492  * fpos(fsat(x)) = fsat(x)
493  * fsat(fsat_signed(x)) = fsat(x)
494  * fsat(fpos(x)) = fsat(x)
495  *
496  * So by cases any composition of output modifiers is equivalent to
497  * fsat alone.
498  */
499 static unsigned
mir_determine_float_outmod(compiler_context * ctx,nir_dest ** dest,unsigned prior_outmod)500 mir_determine_float_outmod(compiler_context *ctx, nir_dest **dest, unsigned prior_outmod)
501 {
502         bool fpos = mir_accept_dest_mod(ctx, dest, nir_op_fclamp_pos);
503         bool fsat = mir_accept_dest_mod(ctx, dest, nir_op_fsat);
504         bool ssat = mir_accept_dest_mod(ctx, dest, nir_op_fsat_signed);
505         bool prior = (prior_outmod != midgard_outmod_none);
506         int count = (int) prior + (int) fpos + (int) ssat + (int) fsat;
507 
508         return ((count > 1) || fsat) ? midgard_outmod_sat :
509                                 fpos ? midgard_outmod_pos :
510                                 ssat ? midgard_outmod_sat_signed :
511                                 prior_outmod;
512 }
513 
514 static void
mir_copy_src(midgard_instruction * ins,nir_alu_instr * instr,unsigned i,unsigned to,bool * abs,bool * neg,bool * not,enum midgard_roundmode * roundmode,bool is_int,unsigned bcast_count)515 mir_copy_src(midgard_instruction *ins, nir_alu_instr *instr, unsigned i, unsigned to, bool *abs, bool *neg, bool *not, enum midgard_roundmode *roundmode, bool is_int, unsigned bcast_count)
516 {
517         nir_alu_src src = instr->src[i];
518 
519         if (!is_int) {
520                 if (pan_has_source_mod(&src, nir_op_fneg))
521                         *neg = !(*neg);
522 
523                 if (pan_has_source_mod(&src, nir_op_fabs))
524                         *abs = true;
525         }
526 
527         if (nir_accepts_inot(instr->op, i) && pan_has_source_mod(&src, nir_op_inot))
528                 *not = true;
529 
530         if (roundmode) {
531                 if (pan_has_source_mod(&src, nir_op_fround_even))
532                         *roundmode = MIDGARD_RTE;
533 
534                 if (pan_has_source_mod(&src, nir_op_ftrunc))
535                         *roundmode = MIDGARD_RTZ;
536 
537                 if (pan_has_source_mod(&src, nir_op_ffloor))
538                         *roundmode = MIDGARD_RTN;
539 
540                 if (pan_has_source_mod(&src, nir_op_fceil))
541                         *roundmode = MIDGARD_RTP;
542         }
543 
544         unsigned bits = nir_src_bit_size(src.src);
545 
546         ins->src[to] = nir_src_index(NULL, &src.src);
547         ins->src_types[to] = nir_op_infos[instr->op].input_types[i] | bits;
548 
549         for (unsigned c = 0; c < NIR_MAX_VEC_COMPONENTS; ++c) {
550                 ins->swizzle[to][c] = src.swizzle[
551                         (!bcast_count || c < bcast_count) ? c :
552                                 (bcast_count - 1)];
553         }
554 }
555 
556 /* Midgard features both fcsel and icsel, depending on whether you want int or
557  * float modifiers. NIR's csel is typeless, so we want a heuristic to guess if
558  * we should emit an int or float csel depending on what modifiers could be
559  * placed. In the absense of modifiers, this is probably arbitrary. */
560 
561 static bool
mir_is_bcsel_float(nir_alu_instr * instr)562 mir_is_bcsel_float(nir_alu_instr *instr)
563 {
564         nir_op intmods[] = {
565                 nir_op_i2i8, nir_op_i2i16,
566                 nir_op_i2i32, nir_op_i2i64
567         };
568 
569         nir_op floatmods[] = {
570                 nir_op_fabs, nir_op_fneg,
571                 nir_op_f2f16, nir_op_f2f32,
572                 nir_op_f2f64
573         };
574 
575         nir_op floatdestmods[] = {
576                 nir_op_fsat, nir_op_fsat_signed, nir_op_fclamp_pos,
577                 nir_op_f2f16, nir_op_f2f32
578         };
579 
580         signed score = 0;
581 
582         for (unsigned i = 1; i < 3; ++i) {
583                 nir_alu_src s = instr->src[i];
584                 for (unsigned q = 0; q < ARRAY_SIZE(intmods); ++q) {
585                         if (pan_has_source_mod(&s, intmods[q]))
586                                 score--;
587                 }
588         }
589 
590         for (unsigned i = 1; i < 3; ++i) {
591                 nir_alu_src s = instr->src[i];
592                 for (unsigned q = 0; q < ARRAY_SIZE(floatmods); ++q) {
593                         if (pan_has_source_mod(&s, floatmods[q]))
594                                 score++;
595                 }
596         }
597 
598         for (unsigned q = 0; q < ARRAY_SIZE(floatdestmods); ++q) {
599                 nir_dest *dest = &instr->dest.dest;
600                 if (pan_has_dest_mod(&dest, floatdestmods[q]))
601                         score++;
602         }
603 
604         return (score > 0);
605 }
606 
607 static void
emit_alu(compiler_context * ctx,nir_alu_instr * instr)608 emit_alu(compiler_context *ctx, nir_alu_instr *instr)
609 {
610         nir_dest *dest = &instr->dest.dest;
611 
612         if (dest->is_ssa && BITSET_TEST(ctx->already_emitted, dest->ssa.index))
613                 return;
614 
615         /* Derivatives end up emitted on the texture pipe, not the ALUs. This
616          * is handled elsewhere */
617 
618         if (instr->op == nir_op_fddx || instr->op == nir_op_fddy) {
619                 midgard_emit_derivatives(ctx, instr);
620                 return;
621         }
622 
623         bool is_ssa = dest->is_ssa;
624 
625         unsigned nr_components = nir_dest_num_components(*dest);
626         unsigned nr_inputs = nir_op_infos[instr->op].num_inputs;
627         unsigned op = 0;
628 
629         /* Number of components valid to check for the instruction (the rest
630          * will be forced to the last), or 0 to use as-is. Relevant as
631          * ball-type instructions have a channel count in NIR but are all vec4
632          * in Midgard */
633 
634         unsigned broadcast_swizzle = 0;
635 
636         /* Should we swap arguments? */
637         bool flip_src12 = false;
638 
639         ASSERTED unsigned src_bitsize = nir_src_bit_size(instr->src[0].src);
640         ASSERTED unsigned dst_bitsize = nir_dest_bit_size(*dest);
641 
642         enum midgard_roundmode roundmode = MIDGARD_RTE;
643 
644         switch (instr->op) {
645                 ALU_CASE(fadd, fadd);
646                 ALU_CASE(fmul, fmul);
647                 ALU_CASE(fmin, fmin);
648                 ALU_CASE(fmax, fmax);
649                 ALU_CASE(imin, imin);
650                 ALU_CASE(imax, imax);
651                 ALU_CASE(umin, umin);
652                 ALU_CASE(umax, umax);
653                 ALU_CASE(ffloor, ffloor);
654                 ALU_CASE(fround_even, froundeven);
655                 ALU_CASE(ftrunc, ftrunc);
656                 ALU_CASE(fceil, fceil);
657                 ALU_CASE(fdot3, fdot3);
658                 ALU_CASE(fdot4, fdot4);
659                 ALU_CASE(iadd, iadd);
660                 ALU_CASE(isub, isub);
661                 ALU_CASE(imul, imul);
662                 ALU_CASE(imul_high, imul);
663                 ALU_CASE(umul_high, imul);
664 
665                 /* Zero shoved as second-arg */
666                 ALU_CASE(iabs, iabsdiff);
667 
668                 ALU_CASE(uabs_isub, iabsdiff);
669                 ALU_CASE(uabs_usub, uabsdiff);
670 
671                 ALU_CASE(mov, imov);
672 
673                 ALU_CASE_CMP(feq32, feq);
674                 ALU_CASE_CMP(fneu32, fne);
675                 ALU_CASE_CMP(flt32, flt);
676                 ALU_CASE_CMP(ieq32, ieq);
677                 ALU_CASE_CMP(ine32, ine);
678                 ALU_CASE_CMP(ilt32, ilt);
679                 ALU_CASE_CMP(ult32, ult);
680 
681                 /* We don't have a native b2f32 instruction. Instead, like many
682                  * GPUs, we exploit booleans as 0/~0 for false/true, and
683                  * correspondingly AND
684                  * by 1.0 to do the type conversion. For the moment, prime us
685                  * to emit:
686                  *
687                  * iand [whatever], #0
688                  *
689                  * At the end of emit_alu (as MIR), we'll fix-up the constant
690                  */
691 
692                 ALU_CASE_CMP(b2f32, iand);
693                 ALU_CASE_CMP(b2f16, iand);
694                 ALU_CASE_CMP(b2i32, iand);
695 
696                 /* Likewise, we don't have a dedicated f2b32 instruction, but
697                  * we can do a "not equal to 0.0" test. */
698 
699                 ALU_CASE_CMP(f2b32, fne);
700                 ALU_CASE_CMP(i2b32, ine);
701 
702                 ALU_CASE(frcp, frcp);
703                 ALU_CASE(frsq, frsqrt);
704                 ALU_CASE(fsqrt, fsqrt);
705                 ALU_CASE(fexp2, fexp2);
706                 ALU_CASE(flog2, flog2);
707 
708                 ALU_CASE_RTZ(f2i64, f2i_rte);
709                 ALU_CASE_RTZ(f2u64, f2u_rte);
710                 ALU_CASE_RTZ(i2f64, i2f_rte);
711                 ALU_CASE_RTZ(u2f64, u2f_rte);
712 
713                 ALU_CASE_RTZ(f2i32, f2i_rte);
714                 ALU_CASE_RTZ(f2u32, f2u_rte);
715                 ALU_CASE_RTZ(i2f32, i2f_rte);
716                 ALU_CASE_RTZ(u2f32, u2f_rte);
717 
718                 ALU_CASE_RTZ(f2i8, f2i_rte);
719                 ALU_CASE_RTZ(f2u8, f2u_rte);
720 
721                 ALU_CASE_RTZ(f2i16, f2i_rte);
722                 ALU_CASE_RTZ(f2u16, f2u_rte);
723                 ALU_CASE_RTZ(i2f16, i2f_rte);
724                 ALU_CASE_RTZ(u2f16, u2f_rte);
725 
726                 ALU_CASE(fsin, fsin);
727                 ALU_CASE(fcos, fcos);
728 
729                 /* We'll get 0 in the second arg, so:
730                  * ~a = ~(a | 0) = nor(a, 0) */
731                 ALU_CASE(inot, inor);
732                 ALU_CASE(iand, iand);
733                 ALU_CASE(ior, ior);
734                 ALU_CASE(ixor, ixor);
735                 ALU_CASE(ishl, ishl);
736                 ALU_CASE(ishr, iasr);
737                 ALU_CASE(ushr, ilsr);
738 
739                 ALU_CASE_BCAST(b32all_fequal2, fball_eq, 2);
740                 ALU_CASE_BCAST(b32all_fequal3, fball_eq, 3);
741                 ALU_CASE_CMP(b32all_fequal4, fball_eq);
742 
743                 ALU_CASE_BCAST(b32any_fnequal2, fbany_neq, 2);
744                 ALU_CASE_BCAST(b32any_fnequal3, fbany_neq, 3);
745                 ALU_CASE_CMP(b32any_fnequal4, fbany_neq);
746 
747                 ALU_CASE_BCAST(b32all_iequal2, iball_eq, 2);
748                 ALU_CASE_BCAST(b32all_iequal3, iball_eq, 3);
749                 ALU_CASE_CMP(b32all_iequal4, iball_eq);
750 
751                 ALU_CASE_BCAST(b32any_inequal2, ibany_neq, 2);
752                 ALU_CASE_BCAST(b32any_inequal3, ibany_neq, 3);
753                 ALU_CASE_CMP(b32any_inequal4, ibany_neq);
754 
755                 /* Source mods will be shoved in later */
756                 ALU_CASE(fabs, fmov);
757                 ALU_CASE(fneg, fmov);
758                 ALU_CASE(fsat, fmov);
759                 ALU_CASE(fsat_signed, fmov);
760                 ALU_CASE(fclamp_pos, fmov);
761 
762         /* For size conversion, we use a move. Ideally though we would squash
763          * these ops together; maybe that has to happen after in NIR as part of
764          * propagation...? An earlier algebraic pass ensured we step down by
765          * only / exactly one size. If stepping down, we use a dest override to
766          * reduce the size; if stepping up, we use a larger-sized move with a
767          * half source and a sign/zero-extension modifier */
768 
769         case nir_op_i2i8:
770         case nir_op_i2i16:
771         case nir_op_i2i32:
772         case nir_op_i2i64:
773         case nir_op_u2u8:
774         case nir_op_u2u16:
775         case nir_op_u2u32:
776         case nir_op_u2u64:
777         case nir_op_f2f16:
778         case nir_op_f2f32:
779         case nir_op_f2f64: {
780                 if (instr->op == nir_op_f2f16 || instr->op == nir_op_f2f32 ||
781                     instr->op == nir_op_f2f64)
782                         op = midgard_alu_op_fmov;
783                 else
784                         op = midgard_alu_op_imov;
785 
786                 break;
787         }
788 
789         /* For greater-or-equal, we lower to less-or-equal and flip the
790          * arguments */
791 
792         case nir_op_fge:
793         case nir_op_fge32:
794         case nir_op_ige32:
795         case nir_op_uge32: {
796                 op =
797                         instr->op == nir_op_fge   ? midgard_alu_op_fle :
798                         instr->op == nir_op_fge32 ? midgard_alu_op_fle :
799                         instr->op == nir_op_ige32 ? midgard_alu_op_ile :
800                         instr->op == nir_op_uge32 ? midgard_alu_op_ule :
801                         0;
802 
803                 flip_src12 = true;
804                 ALU_CHECK_CMP();
805                 break;
806         }
807 
808         case nir_op_b32csel: {
809                 bool mixed = nir_is_non_scalar_swizzle(&instr->src[0], nr_components);
810                 bool is_float = mir_is_bcsel_float(instr);
811                 op = is_float ?
812                         (mixed ? midgard_alu_op_fcsel_v : midgard_alu_op_fcsel) :
813                         (mixed ? midgard_alu_op_icsel_v : midgard_alu_op_icsel);
814 
815                 break;
816         }
817 
818         case nir_op_unpack_32_2x16:
819         case nir_op_unpack_32_4x8:
820         case nir_op_pack_32_2x16:
821         case nir_op_pack_32_4x8: {
822                 op = midgard_alu_op_imov;
823                 break;
824         }
825 
826         default:
827                 DBG("Unhandled ALU op %s\n", nir_op_infos[instr->op].name);
828                 assert(0);
829                 return;
830         }
831 
832         /* Promote imov to fmov if it might help inline a constant */
833         if (op == midgard_alu_op_imov && nir_src_is_const(instr->src[0].src)
834                         && nir_src_bit_size(instr->src[0].src) == 32
835                         && nir_is_same_comp_swizzle(instr->src[0].swizzle,
836                                 nir_src_num_components(instr->src[0].src))) {
837                 op = midgard_alu_op_fmov;
838         }
839 
840         /* Midgard can perform certain modifiers on output of an ALU op */
841 
842         unsigned outmod = 0;
843         bool is_int = midgard_is_integer_op(op);
844 
845         if (instr->op == nir_op_umul_high || instr->op == nir_op_imul_high) {
846                 outmod = midgard_outmod_int_high;
847         } else if (midgard_is_integer_out_op(op)) {
848                 outmod = midgard_outmod_int_wrap;
849         } else if (instr->op == nir_op_fsat) {
850                 outmod = midgard_outmod_sat;
851         } else if (instr->op == nir_op_fsat_signed) {
852                 outmod = midgard_outmod_sat_signed;
853         } else if (instr->op == nir_op_fclamp_pos) {
854                 outmod = midgard_outmod_pos;
855         }
856 
857         /* Fetch unit, quirks, etc information */
858         unsigned opcode_props = alu_opcode_props[op].props;
859         bool quirk_flipped_r24 = opcode_props & QUIRK_FLIPPED_R24;
860 
861         if (!midgard_is_integer_out_op(op)) {
862                 outmod = mir_determine_float_outmod(ctx, &dest, outmod);
863         }
864 
865         midgard_instruction ins = {
866                 .type = TAG_ALU_4,
867                 .dest = nir_dest_index(dest),
868                 .dest_type = nir_op_infos[instr->op].output_type
869                         | nir_dest_bit_size(*dest),
870                 .roundmode = roundmode,
871         };
872 
873         enum midgard_roundmode *roundptr = (opcode_props & MIDGARD_ROUNDS) ?
874                 &ins.roundmode : NULL;
875 
876         for (unsigned i = nr_inputs; i < ARRAY_SIZE(ins.src); ++i)
877                 ins.src[i] = ~0;
878 
879         if (quirk_flipped_r24) {
880                 ins.src[0] = ~0;
881                 mir_copy_src(&ins, instr, 0, 1, &ins.src_abs[1], &ins.src_neg[1], &ins.src_invert[1], roundptr, is_int, broadcast_swizzle);
882         } else {
883                 for (unsigned i = 0; i < nr_inputs; ++i) {
884                         unsigned to = i;
885 
886                         if (instr->op == nir_op_b32csel) {
887                                 /* The condition is the first argument; move
888                                  * the other arguments up one to be a binary
889                                  * instruction for Midgard with the condition
890                                  * last */
891 
892                                 if (i == 0)
893                                         to = 2;
894                                 else if (flip_src12)
895                                         to = 2 - i;
896                                 else
897                                         to = i - 1;
898                         } else if (flip_src12) {
899                                 to = 1 - to;
900                         }
901 
902                         mir_copy_src(&ins, instr, i, to, &ins.src_abs[to], &ins.src_neg[to], &ins.src_invert[to], roundptr, is_int, broadcast_swizzle);
903 
904                         /* (!c) ? a : b = c ? b : a */
905                         if (instr->op == nir_op_b32csel && ins.src_invert[2]) {
906                                 ins.src_invert[2] = false;
907                                 flip_src12 ^= true;
908                         }
909                 }
910         }
911 
912         if (instr->op == nir_op_fneg || instr->op == nir_op_fabs) {
913                 /* Lowered to move */
914                 if (instr->op == nir_op_fneg)
915                         ins.src_neg[1] ^= true;
916 
917                 if (instr->op == nir_op_fabs)
918                         ins.src_abs[1] = true;
919         }
920 
921         ins.mask = mask_of(nr_components);
922 
923         /* Apply writemask if non-SSA, keeping in mind that we can't write to
924          * components that don't exist. Note modifier => SSA => !reg => no
925          * writemask, so we don't have to worry about writemasks here.*/
926 
927         if (!is_ssa)
928                 ins.mask &= instr->dest.write_mask;
929 
930         ins.op = op;
931         ins.outmod = outmod;
932 
933         /* Late fixup for emulated instructions */
934 
935         if (instr->op == nir_op_b2f32 || instr->op == nir_op_b2i32) {
936                 /* Presently, our second argument is an inline #0 constant.
937                  * Switch over to an embedded 1.0 constant (that can't fit
938                  * inline, since we're 32-bit, not 16-bit like the inline
939                  * constants) */
940 
941                 ins.has_inline_constant = false;
942                 ins.src[1] = SSA_FIXED_REGISTER(REGISTER_CONSTANT);
943                 ins.src_types[1] = nir_type_float32;
944                 ins.has_constants = true;
945 
946                 if (instr->op == nir_op_b2f32)
947                         ins.constants.f32[0] = 1.0f;
948                 else
949                         ins.constants.i32[0] = 1;
950 
951                 for (unsigned c = 0; c < 16; ++c)
952                         ins.swizzle[1][c] = 0;
953         } else if (instr->op == nir_op_b2f16) {
954                 ins.src[1] = SSA_FIXED_REGISTER(REGISTER_CONSTANT);
955                 ins.src_types[1] = nir_type_float16;
956                 ins.has_constants = true;
957                 ins.constants.i16[0] = _mesa_float_to_half(1.0);
958 
959                 for (unsigned c = 0; c < 16; ++c)
960                         ins.swizzle[1][c] = 0;
961         } else if (nr_inputs == 1 && !quirk_flipped_r24) {
962                 /* Lots of instructions need a 0 plonked in */
963                 ins.has_inline_constant = false;
964                 ins.src[1] = SSA_FIXED_REGISTER(REGISTER_CONSTANT);
965                 ins.src_types[1] = ins.src_types[0];
966                 ins.has_constants = true;
967                 ins.constants.u32[0] = 0;
968 
969                 for (unsigned c = 0; c < 16; ++c)
970                         ins.swizzle[1][c] = 0;
971         } else if (instr->op == nir_op_pack_32_2x16) {
972                 ins.dest_type = nir_type_uint16;
973                 ins.mask = mask_of(nr_components * 2);
974                 ins.is_pack = true;
975         } else if (instr->op == nir_op_pack_32_4x8) {
976                 ins.dest_type = nir_type_uint8;
977                 ins.mask = mask_of(nr_components * 4);
978                 ins.is_pack = true;
979         } else if (instr->op == nir_op_unpack_32_2x16) {
980                 ins.dest_type = nir_type_uint32;
981                 ins.mask = mask_of(nr_components >> 1);
982                 ins.is_pack = true;
983         } else if (instr->op == nir_op_unpack_32_4x8) {
984                 ins.dest_type = nir_type_uint32;
985                 ins.mask = mask_of(nr_components >> 2);
986                 ins.is_pack = true;
987         }
988 
989         if ((opcode_props & UNITS_ALL) == UNIT_VLUT) {
990                 /* To avoid duplicating the lookup tables (probably), true LUT
991                  * instructions can only operate as if they were scalars. Lower
992                  * them here by changing the component. */
993 
994                 unsigned orig_mask = ins.mask;
995 
996                 unsigned swizzle_back[MIR_VEC_COMPONENTS];
997                 memcpy(&swizzle_back, ins.swizzle[0], sizeof(swizzle_back));
998 
999                 midgard_instruction ins_split[MIR_VEC_COMPONENTS];
1000                 unsigned ins_count = 0;
1001 
1002                 for (int i = 0; i < nr_components; ++i) {
1003                         /* Mask the associated component, dropping the
1004                          * instruction if needed */
1005 
1006                         ins.mask = 1 << i;
1007                         ins.mask &= orig_mask;
1008 
1009                         for (unsigned j = 0; j < ins_count; ++j) {
1010                                 if (swizzle_back[i] == ins_split[j].swizzle[0][0]) {
1011                                         ins_split[j].mask |= ins.mask;
1012                                         ins.mask = 0;
1013                                         break;
1014                                 }
1015                         }
1016 
1017                         if (!ins.mask)
1018                                 continue;
1019 
1020                         for (unsigned j = 0; j < MIR_VEC_COMPONENTS; ++j)
1021                                 ins.swizzle[0][j] = swizzle_back[i]; /* Pull from the correct component */
1022 
1023                         ins_split[ins_count] = ins;
1024 
1025                         ++ins_count;
1026                 }
1027 
1028                 for (unsigned i = 0; i < ins_count; ++i) {
1029                         emit_mir_instruction(ctx, ins_split[i]);
1030                 }
1031         } else {
1032                 emit_mir_instruction(ctx, ins);
1033         }
1034 }
1035 
1036 #undef ALU_CASE
1037 
1038 static void
mir_set_intr_mask(nir_instr * instr,midgard_instruction * ins,bool is_read)1039 mir_set_intr_mask(nir_instr *instr, midgard_instruction *ins, bool is_read)
1040 {
1041         nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
1042         unsigned nir_mask = 0;
1043         unsigned dsize = 0;
1044 
1045         if (is_read) {
1046                 nir_mask = mask_of(nir_intrinsic_dest_components(intr));
1047                 dsize = nir_dest_bit_size(intr->dest);
1048         } else {
1049                 nir_mask = nir_intrinsic_write_mask(intr);
1050                 dsize = 32;
1051         }
1052 
1053         /* Once we have the NIR mask, we need to normalize to work in 32-bit space */
1054         unsigned bytemask = pan_to_bytemask(dsize, nir_mask);
1055         ins->dest_type = nir_type_uint | dsize;
1056         mir_set_bytemask(ins, bytemask);
1057 }
1058 
1059 /* Uniforms and UBOs use a shared code path, as uniforms are just (slightly
1060  * optimized) versions of UBO #0 */
1061 
1062 static midgard_instruction *
emit_ubo_read(compiler_context * ctx,nir_instr * instr,unsigned dest,unsigned offset,nir_src * indirect_offset,unsigned indirect_shift,unsigned index)1063 emit_ubo_read(
1064         compiler_context *ctx,
1065         nir_instr *instr,
1066         unsigned dest,
1067         unsigned offset,
1068         nir_src *indirect_offset,
1069         unsigned indirect_shift,
1070         unsigned index)
1071 {
1072         /* TODO: half-floats */
1073 
1074         midgard_instruction ins = m_ld_ubo_int4(dest, 0);
1075         ins.constants.u32[0] = offset;
1076 
1077         if (instr->type == nir_instr_type_intrinsic)
1078                 mir_set_intr_mask(instr, &ins, true);
1079 
1080         if (indirect_offset) {
1081                 ins.src[2] = nir_src_index(ctx, indirect_offset);
1082                 ins.src_types[2] = nir_type_uint32;
1083                 ins.load_store.arg_2 = (indirect_shift << 5);
1084 
1085                 /* X component for the whole swizzle to prevent register
1086                  * pressure from ballooning from the extra components */
1087                 for (unsigned i = 0; i < ARRAY_SIZE(ins.swizzle[2]); ++i)
1088                         ins.swizzle[2][i] = 0;
1089         } else {
1090                 ins.load_store.arg_2 = 0x1E;
1091         }
1092 
1093         ins.load_store.arg_1 = index;
1094 
1095         return emit_mir_instruction(ctx, ins);
1096 }
1097 
1098 /* Globals are like UBOs if you squint. And shared memory is like globals if
1099  * you squint even harder */
1100 
1101 static void
emit_global(compiler_context * ctx,nir_instr * instr,bool is_read,unsigned srcdest,nir_src * offset,bool is_shared)1102 emit_global(
1103         compiler_context *ctx,
1104         nir_instr *instr,
1105         bool is_read,
1106         unsigned srcdest,
1107         nir_src *offset,
1108         bool is_shared)
1109 {
1110         /* TODO: types */
1111 
1112         midgard_instruction ins;
1113 
1114         if (is_read)
1115                 ins = m_ld_int4(srcdest, 0);
1116         else
1117                 ins = m_st_int4(srcdest, 0);
1118 
1119         mir_set_offset(ctx, &ins, offset, is_shared);
1120         mir_set_intr_mask(instr, &ins, is_read);
1121 
1122         /* Set a valid swizzle for masked out components */
1123         assert(ins.mask);
1124         unsigned first_component = __builtin_ffs(ins.mask) - 1;
1125 
1126         for (unsigned i = 0; i < ARRAY_SIZE(ins.swizzle[0]); ++i) {
1127                 if (!(ins.mask & (1 << i)))
1128                         ins.swizzle[0][i] = first_component;
1129         }
1130 
1131         emit_mir_instruction(ctx, ins);
1132 }
1133 
1134 /* If is_shared is off, the only other possible value are globals, since
1135  * SSBO's are being lowered to globals through a NIR pass. */
1136 static void
emit_atomic(compiler_context * ctx,nir_intrinsic_instr * instr,bool is_shared,midgard_load_store_op op)1137 emit_atomic(
1138         compiler_context *ctx,
1139         nir_intrinsic_instr *instr,
1140         bool is_shared,
1141         midgard_load_store_op op)
1142 {
1143         unsigned bitsize = nir_src_bit_size(instr->src[1]);
1144         nir_alu_type type =
1145                 (op == midgard_op_atomic_imin || op == midgard_op_atomic_imax) ?
1146                 nir_type_int : nir_type_uint;
1147 
1148         unsigned dest = nir_dest_index(&instr->dest);
1149         unsigned val = nir_src_index(ctx, &instr->src[1]);
1150         emit_explicit_constant(ctx, val, val);
1151 
1152         midgard_instruction ins = {
1153                 .type = TAG_LOAD_STORE_4,
1154                 .mask = 0xF,
1155                 .dest = dest,
1156                 .src = { ~0, ~0, ~0, val },
1157                 .src_types = { 0, 0, 0, type | bitsize },
1158                 .op = op
1159         };
1160 
1161         nir_src *src_offset = nir_get_io_offset_src(instr);
1162 
1163         /* cmpxchg takes an extra value in arg_2, so we don't use it for the offset */
1164         if (op == midgard_op_atomic_cmpxchg) {
1165                 unsigned addr = nir_src_index(ctx, src_offset);
1166 
1167                 ins.src[1] = addr;
1168                 ins.src_types[1] = nir_type_uint | nir_src_bit_size(*src_offset);
1169 
1170                 unsigned xchg_val = nir_src_index(ctx, &instr->src[2]);
1171                 emit_explicit_constant(ctx, xchg_val, xchg_val);
1172 
1173                 ins.src[2] = val;
1174                 ins.src_types[2] = type | bitsize;
1175                 ins.src[3] = xchg_val;
1176 
1177                 if (is_shared)
1178                         ins.load_store.arg_1 |= 0x6E;
1179         } else {
1180                 mir_set_offset(ctx, &ins, src_offset, is_shared);
1181         }
1182 
1183         mir_set_intr_mask(&instr->instr, &ins, true);
1184 
1185         emit_mir_instruction(ctx, ins);
1186 }
1187 
1188 static void
emit_varying_read(compiler_context * ctx,unsigned dest,unsigned offset,unsigned nr_comp,unsigned component,nir_src * indirect_offset,nir_alu_type type,bool flat)1189 emit_varying_read(
1190         compiler_context *ctx,
1191         unsigned dest, unsigned offset,
1192         unsigned nr_comp, unsigned component,
1193         nir_src *indirect_offset, nir_alu_type type, bool flat)
1194 {
1195         /* XXX: Half-floats? */
1196         /* TODO: swizzle, mask */
1197 
1198         midgard_instruction ins = m_ld_vary_32(dest, offset);
1199         ins.mask = mask_of(nr_comp);
1200         ins.dest_type = type;
1201 
1202         if (type == nir_type_float16) {
1203                 /* Ensure we are aligned so we can pack it later */
1204                 ins.mask = mask_of(ALIGN_POT(nr_comp, 2));
1205         }
1206 
1207         for (unsigned i = 0; i < ARRAY_SIZE(ins.swizzle[0]); ++i)
1208                 ins.swizzle[0][i] = MIN2(i + component, COMPONENT_W);
1209 
1210         midgard_varying_parameter p = {
1211                 .is_varying = 1,
1212                 .interpolation = midgard_interp_default,
1213                 .flat = flat,
1214         };
1215 
1216         unsigned u;
1217         memcpy(&u, &p, sizeof(p));
1218         ins.load_store.varying_parameters = u;
1219 
1220         if (indirect_offset) {
1221                 ins.src[2] = nir_src_index(ctx, indirect_offset);
1222                 ins.src_types[2] = nir_type_uint32;
1223         } else
1224                 ins.load_store.arg_2 = 0x1E;
1225 
1226         ins.load_store.arg_1 = 0x9E;
1227 
1228         /* Use the type appropriate load */
1229         switch (type) {
1230         case nir_type_uint32:
1231         case nir_type_bool32:
1232                 ins.op = midgard_op_ld_vary_32u;
1233                 break;
1234         case nir_type_int32:
1235                 ins.op = midgard_op_ld_vary_32i;
1236                 break;
1237         case nir_type_float32:
1238                 ins.op = midgard_op_ld_vary_32;
1239                 break;
1240         case nir_type_float16:
1241                 ins.op = midgard_op_ld_vary_16;
1242                 break;
1243         default:
1244                 unreachable("Attempted to load unknown type");
1245                 break;
1246         }
1247 
1248         emit_mir_instruction(ctx, ins);
1249 }
1250 
1251 static void
emit_attr_read(compiler_context * ctx,unsigned dest,unsigned offset,unsigned nr_comp,nir_alu_type t)1252 emit_attr_read(
1253         compiler_context *ctx,
1254         unsigned dest, unsigned offset,
1255         unsigned nr_comp, nir_alu_type t)
1256 {
1257         midgard_instruction ins = m_ld_attr_32(dest, offset);
1258         ins.load_store.arg_1 = 0x1E;
1259         ins.load_store.arg_2 = 0x1E;
1260         ins.mask = mask_of(nr_comp);
1261 
1262         /* Use the type appropriate load */
1263         switch (t) {
1264         case nir_type_uint:
1265         case nir_type_bool:
1266                 ins.op = midgard_op_ld_attr_32u;
1267                 break;
1268         case nir_type_int:
1269                 ins.op = midgard_op_ld_attr_32i;
1270                 break;
1271         case nir_type_float:
1272                 ins.op = midgard_op_ld_attr_32;
1273                 break;
1274         default:
1275                 unreachable("Attempted to load unknown type");
1276                 break;
1277         }
1278 
1279         emit_mir_instruction(ctx, ins);
1280 }
1281 
1282 static void
emit_sysval_read(compiler_context * ctx,nir_instr * instr,unsigned nr_components,unsigned offset)1283 emit_sysval_read(compiler_context *ctx, nir_instr *instr,
1284                 unsigned nr_components, unsigned offset)
1285 {
1286         nir_dest nir_dest;
1287 
1288         /* Figure out which uniform this is */
1289         int sysval = panfrost_sysval_for_instr(instr, &nir_dest);
1290         void *val = _mesa_hash_table_u64_search(ctx->sysvals.sysval_to_id, sysval);
1291 
1292         unsigned dest = nir_dest_index(&nir_dest);
1293 
1294         /* Sysvals are prefix uniforms */
1295         unsigned uniform = ((uintptr_t) val) - 1;
1296 
1297         /* Emit the read itself -- this is never indirect */
1298         midgard_instruction *ins =
1299                 emit_ubo_read(ctx, instr, dest, (uniform * 16) + offset, NULL, 0, 0);
1300 
1301         ins->mask = mask_of(nr_components);
1302 }
1303 
1304 static unsigned
compute_builtin_arg(nir_op op)1305 compute_builtin_arg(nir_op op)
1306 {
1307         switch (op) {
1308         case nir_intrinsic_load_work_group_id:
1309                 return 0x14;
1310         case nir_intrinsic_load_local_invocation_id:
1311                 return 0x10;
1312         default:
1313                 unreachable("Invalid compute paramater loaded");
1314         }
1315 }
1316 
1317 static void
emit_fragment_store(compiler_context * ctx,unsigned src,unsigned src_z,unsigned src_s,enum midgard_rt_id rt)1318 emit_fragment_store(compiler_context *ctx, unsigned src, unsigned src_z, unsigned src_s, enum midgard_rt_id rt)
1319 {
1320         assert(rt < ARRAY_SIZE(ctx->writeout_branch));
1321 
1322         midgard_instruction *br = ctx->writeout_branch[rt];
1323 
1324         assert(!br);
1325 
1326         emit_explicit_constant(ctx, src, src);
1327 
1328         struct midgard_instruction ins =
1329                 v_branch(false, false);
1330 
1331         bool depth_only = (rt == MIDGARD_ZS_RT);
1332 
1333         ins.writeout = depth_only ? 0 : PAN_WRITEOUT_C;
1334 
1335         /* Add dependencies */
1336         ins.src[0] = src;
1337         ins.src_types[0] = nir_type_uint32;
1338         ins.constants.u32[0] = depth_only ? 0xFF : (rt - MIDGARD_COLOR_RT0) * 0x100;
1339         for (int i = 0; i < 4; ++i)
1340                 ins.swizzle[0][i] = i;
1341 
1342         if (~src_z) {
1343                 emit_explicit_constant(ctx, src_z, src_z);
1344                 ins.src[2] = src_z;
1345                 ins.src_types[2] = nir_type_uint32;
1346                 ins.writeout |= PAN_WRITEOUT_Z;
1347         }
1348         if (~src_s) {
1349                 emit_explicit_constant(ctx, src_s, src_s);
1350                 ins.src[3] = src_s;
1351                 ins.src_types[3] = nir_type_uint32;
1352                 ins.writeout |= PAN_WRITEOUT_S;
1353         }
1354 
1355         /* Emit the branch */
1356         br = emit_mir_instruction(ctx, ins);
1357         schedule_barrier(ctx);
1358         ctx->writeout_branch[rt] = br;
1359 
1360         /* Push our current location = current block count - 1 = where we'll
1361          * jump to. Maybe a bit too clever for my own good */
1362 
1363         br->branch.target_block = ctx->block_count - 1;
1364 }
1365 
1366 static void
emit_compute_builtin(compiler_context * ctx,nir_intrinsic_instr * instr)1367 emit_compute_builtin(compiler_context *ctx, nir_intrinsic_instr *instr)
1368 {
1369         unsigned reg = nir_dest_index(&instr->dest);
1370         midgard_instruction ins = m_ld_compute_id(reg, 0);
1371         ins.mask = mask_of(3);
1372         ins.swizzle[0][3] = COMPONENT_X; /* xyzx */
1373         ins.load_store.arg_1 = compute_builtin_arg(instr->intrinsic);
1374         emit_mir_instruction(ctx, ins);
1375 }
1376 
1377 static unsigned
vertex_builtin_arg(nir_op op)1378 vertex_builtin_arg(nir_op op)
1379 {
1380         switch (op) {
1381         case nir_intrinsic_load_vertex_id:
1382                 return PAN_VERTEX_ID;
1383         case nir_intrinsic_load_instance_id:
1384                 return PAN_INSTANCE_ID;
1385         default:
1386                 unreachable("Invalid vertex builtin");
1387         }
1388 }
1389 
1390 static void
emit_vertex_builtin(compiler_context * ctx,nir_intrinsic_instr * instr)1391 emit_vertex_builtin(compiler_context *ctx, nir_intrinsic_instr *instr)
1392 {
1393         unsigned reg = nir_dest_index(&instr->dest);
1394         emit_attr_read(ctx, reg, vertex_builtin_arg(instr->intrinsic), 1, nir_type_int);
1395 }
1396 
1397 static void
emit_special(compiler_context * ctx,nir_intrinsic_instr * instr,unsigned idx)1398 emit_special(compiler_context *ctx, nir_intrinsic_instr *instr, unsigned idx)
1399 {
1400         unsigned reg = nir_dest_index(&instr->dest);
1401 
1402         midgard_instruction ld = m_ld_color_buffer_32u(reg, 0);
1403         ld.op = midgard_op_ld_color_buffer_32u_old;
1404         ld.load_store.address = idx;
1405         ld.load_store.arg_2 = 0x1E;
1406 
1407         for (int i = 0; i < 4; ++i)
1408                 ld.swizzle[0][i] = COMPONENT_X;
1409 
1410         emit_mir_instruction(ctx, ld);
1411 }
1412 
1413 static void
emit_control_barrier(compiler_context * ctx)1414 emit_control_barrier(compiler_context *ctx)
1415 {
1416         midgard_instruction ins = {
1417                 .type = TAG_TEXTURE_4,
1418                 .dest = ~0,
1419                 .src = { ~0, ~0, ~0, ~0 },
1420                 .op = TEXTURE_OP_BARRIER,
1421         };
1422 
1423         emit_mir_instruction(ctx, ins);
1424 }
1425 
1426 static unsigned
mir_get_branch_cond(nir_src * src,bool * invert)1427 mir_get_branch_cond(nir_src *src, bool *invert)
1428 {
1429         /* Wrap it. No swizzle since it's a scalar */
1430 
1431         nir_alu_src alu = {
1432                 .src = *src
1433         };
1434 
1435         *invert = pan_has_source_mod(&alu, nir_op_inot);
1436         return nir_src_index(NULL, &alu.src);
1437 }
1438 
1439 static uint8_t
output_load_rt_addr(compiler_context * ctx,nir_intrinsic_instr * instr)1440 output_load_rt_addr(compiler_context *ctx, nir_intrinsic_instr *instr)
1441 {
1442         if (ctx->is_blend)
1443                 return ctx->blend_rt;
1444 
1445         const nir_variable *var;
1446         var = nir_find_variable_with_driver_location(ctx->nir, nir_var_shader_out, nir_intrinsic_base(instr));
1447         assert(var);
1448 
1449         unsigned loc = var->data.location;
1450 
1451         if (loc == FRAG_RESULT_COLOR)
1452                 loc = FRAG_RESULT_DATA0;
1453 
1454         if (loc >= FRAG_RESULT_DATA0)
1455                 return loc - FRAG_RESULT_DATA0;
1456 
1457         if (loc == FRAG_RESULT_DEPTH)
1458                 return 0x1F;
1459         if (loc == FRAG_RESULT_STENCIL)
1460                 return 0x1E;
1461 
1462         unreachable("Invalid RT to load from");
1463 }
1464 
1465 static void
emit_intrinsic(compiler_context * ctx,nir_intrinsic_instr * instr)1466 emit_intrinsic(compiler_context *ctx, nir_intrinsic_instr *instr)
1467 {
1468         unsigned offset = 0, reg;
1469 
1470         switch (instr->intrinsic) {
1471         case nir_intrinsic_discard_if:
1472         case nir_intrinsic_discard: {
1473                 bool conditional = instr->intrinsic == nir_intrinsic_discard_if;
1474                 struct midgard_instruction discard = v_branch(conditional, false);
1475                 discard.branch.target_type = TARGET_DISCARD;
1476 
1477                 if (conditional) {
1478                         discard.src[0] = mir_get_branch_cond(&instr->src[0],
1479                                         &discard.branch.invert_conditional);
1480                         discard.src_types[0] = nir_type_uint32;
1481                 }
1482 
1483                 emit_mir_instruction(ctx, discard);
1484                 schedule_barrier(ctx);
1485 
1486                 break;
1487         }
1488 
1489         case nir_intrinsic_load_uniform:
1490         case nir_intrinsic_load_ubo:
1491         case nir_intrinsic_load_global:
1492         case nir_intrinsic_load_shared:
1493         case nir_intrinsic_load_input:
1494         case nir_intrinsic_load_interpolated_input: {
1495                 bool is_uniform = instr->intrinsic == nir_intrinsic_load_uniform;
1496                 bool is_ubo = instr->intrinsic == nir_intrinsic_load_ubo;
1497                 bool is_global = instr->intrinsic == nir_intrinsic_load_global;
1498                 bool is_shared = instr->intrinsic == nir_intrinsic_load_shared;
1499                 bool is_flat = instr->intrinsic == nir_intrinsic_load_input;
1500                 bool is_interp = instr->intrinsic == nir_intrinsic_load_interpolated_input;
1501 
1502                 /* Get the base type of the intrinsic */
1503                 /* TODO: Infer type? Does it matter? */
1504                 nir_alu_type t =
1505                         (is_ubo || is_global || is_shared) ? nir_type_uint :
1506                         (is_interp) ? nir_type_float :
1507                         nir_intrinsic_dest_type(instr);
1508 
1509                 t = nir_alu_type_get_base_type(t);
1510 
1511                 if (!(is_ubo || is_global)) {
1512                         offset = nir_intrinsic_base(instr);
1513                 }
1514 
1515                 unsigned nr_comp = nir_intrinsic_dest_components(instr);
1516 
1517                 nir_src *src_offset = nir_get_io_offset_src(instr);
1518 
1519                 bool direct = nir_src_is_const(*src_offset);
1520                 nir_src *indirect_offset = direct ? NULL : src_offset;
1521 
1522                 if (direct)
1523                         offset += nir_src_as_uint(*src_offset);
1524 
1525                 /* We may need to apply a fractional offset */
1526                 int component = (is_flat || is_interp) ?
1527                                 nir_intrinsic_component(instr) : 0;
1528                 reg = nir_dest_index(&instr->dest);
1529 
1530                 if (is_uniform && !ctx->is_blend) {
1531                         emit_ubo_read(ctx, &instr->instr, reg, (ctx->sysvals.sysval_count + offset) * 16, indirect_offset, 4, 0);
1532                 } else if (is_ubo) {
1533                         nir_src index = instr->src[0];
1534 
1535                         /* TODO: Is indirect block number possible? */
1536                         assert(nir_src_is_const(index));
1537 
1538                         uint32_t uindex = nir_src_as_uint(index) + 1;
1539                         emit_ubo_read(ctx, &instr->instr, reg, offset, indirect_offset, 0, uindex);
1540                 } else if (is_global || is_shared) {
1541                         emit_global(ctx, &instr->instr, true, reg, src_offset, is_shared);
1542                 } else if (ctx->stage == MESA_SHADER_FRAGMENT && !ctx->is_blend) {
1543                         emit_varying_read(ctx, reg, offset, nr_comp, component, indirect_offset, t | nir_dest_bit_size(instr->dest), is_flat);
1544                 } else if (ctx->is_blend) {
1545                         /* ctx->blend_input will be precoloured to r0/r2, where
1546                          * the input is preloaded */
1547 
1548                         unsigned *input = offset ? &ctx->blend_src1 : &ctx->blend_input;
1549 
1550                         if (*input == ~0)
1551                                 *input = reg;
1552                         else
1553                                 emit_mir_instruction(ctx, v_mov(*input, reg));
1554                 } else if (ctx->stage == MESA_SHADER_VERTEX) {
1555                         emit_attr_read(ctx, reg, offset, nr_comp, t);
1556                 } else {
1557                         DBG("Unknown load\n");
1558                         assert(0);
1559                 }
1560 
1561                 break;
1562         }
1563 
1564         /* Artefact of load_interpolated_input. TODO: other barycentric modes */
1565         case nir_intrinsic_load_barycentric_pixel:
1566         case nir_intrinsic_load_barycentric_centroid:
1567                 break;
1568 
1569         /* Reads 128-bit value raw off the tilebuffer during blending, tasty */
1570 
1571         case nir_intrinsic_load_raw_output_pan: {
1572                 reg = nir_dest_index(&instr->dest);
1573 
1574                 /* T720 and below use different blend opcodes with slightly
1575                  * different semantics than T760 and up */
1576 
1577                 midgard_instruction ld = m_ld_color_buffer_32u(reg, 0);
1578 
1579                 ld.load_store.arg_2 = output_load_rt_addr(ctx, instr);
1580 
1581                 if (nir_src_is_const(instr->src[0])) {
1582                         ld.load_store.arg_1 = nir_src_as_uint(instr->src[0]);
1583                 } else {
1584                         ld.load_store.varying_parameters = 2;
1585                         ld.src[1] = nir_src_index(ctx, &instr->src[0]);
1586                         ld.src_types[1] = nir_type_int32;
1587                 }
1588 
1589                 if (ctx->quirks & MIDGARD_OLD_BLEND) {
1590                         ld.op = midgard_op_ld_color_buffer_32u_old;
1591                         ld.load_store.address = 16;
1592                         ld.load_store.arg_2 = 0x1E;
1593                 }
1594 
1595                 emit_mir_instruction(ctx, ld);
1596                 break;
1597         }
1598 
1599         case nir_intrinsic_load_output: {
1600                 reg = nir_dest_index(&instr->dest);
1601 
1602                 unsigned bits = nir_dest_bit_size(instr->dest);
1603 
1604                 midgard_instruction ld;
1605                 if (bits == 16)
1606                         ld = m_ld_color_buffer_as_fp16(reg, 0);
1607                 else
1608                         ld = m_ld_color_buffer_as_fp32(reg, 0);
1609 
1610                 ld.load_store.arg_2 = output_load_rt_addr(ctx, instr);
1611 
1612                 for (unsigned c = 4; c < 16; ++c)
1613                         ld.swizzle[0][c] = 0;
1614 
1615                 if (ctx->quirks & MIDGARD_OLD_BLEND) {
1616                         if (bits == 16)
1617                                 ld.op = midgard_op_ld_color_buffer_as_fp16_old;
1618                         else
1619                                 ld.op = midgard_op_ld_color_buffer_as_fp32_old;
1620                         ld.load_store.address = 1;
1621                         ld.load_store.arg_2 = 0x1E;
1622                 }
1623 
1624                 emit_mir_instruction(ctx, ld);
1625                 break;
1626         }
1627 
1628         case nir_intrinsic_load_blend_const_color_rgba: {
1629                 assert(ctx->is_blend);
1630                 reg = nir_dest_index(&instr->dest);
1631 
1632                 midgard_instruction ins = v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT), reg);
1633                 ins.has_constants = true;
1634                 memcpy(ins.constants.f32, ctx->blend_constants, sizeof(ctx->blend_constants));
1635                 emit_mir_instruction(ctx, ins);
1636                 break;
1637         }
1638 
1639         case nir_intrinsic_store_output:
1640         case nir_intrinsic_store_combined_output_pan:
1641                 assert(nir_src_is_const(instr->src[1]) && "no indirect outputs");
1642 
1643                 offset = nir_intrinsic_base(instr) + nir_src_as_uint(instr->src[1]);
1644 
1645                 reg = nir_src_index(ctx, &instr->src[0]);
1646 
1647                 if (ctx->stage == MESA_SHADER_FRAGMENT) {
1648                         bool combined = instr->intrinsic ==
1649                                 nir_intrinsic_store_combined_output_pan;
1650 
1651                         const nir_variable *var;
1652                         var = nir_find_variable_with_driver_location(ctx->nir, nir_var_shader_out,
1653                                          nir_intrinsic_base(instr));
1654                         assert(var);
1655 
1656                         /* Dual-source blend writeout is done by leaving the
1657                          * value in r2 for the blend shader to use. */
1658                         if (var->data.index) {
1659                                 if (instr->src[0].is_ssa) {
1660                                         emit_explicit_constant(ctx, reg, reg);
1661 
1662                                         unsigned out = make_compiler_temp(ctx);
1663 
1664                                         midgard_instruction ins = v_mov(reg, out);
1665                                         emit_mir_instruction(ctx, ins);
1666 
1667                                         ctx->blend_src1 = out;
1668                                 } else {
1669                                         ctx->blend_src1 = reg;
1670                                 }
1671 
1672                                 break;
1673                         }
1674 
1675                         enum midgard_rt_id rt;
1676                         if (var->data.location == FRAG_RESULT_COLOR)
1677                                 rt = MIDGARD_COLOR_RT0;
1678                         else if (var->data.location >= FRAG_RESULT_DATA0)
1679                                 rt = MIDGARD_COLOR_RT0 + var->data.location -
1680                                      FRAG_RESULT_DATA0;
1681                         else if (combined)
1682                                 rt = MIDGARD_ZS_RT;
1683                         else
1684                                 unreachable("bad rt");
1685 
1686                         unsigned reg_z = ~0, reg_s = ~0;
1687                         if (combined) {
1688                                 unsigned writeout = nir_intrinsic_component(instr);
1689                                 if (writeout & PAN_WRITEOUT_Z)
1690                                         reg_z = nir_src_index(ctx, &instr->src[2]);
1691                                 if (writeout & PAN_WRITEOUT_S)
1692                                         reg_s = nir_src_index(ctx, &instr->src[3]);
1693                         }
1694 
1695                         emit_fragment_store(ctx, reg, reg_z, reg_s, rt);
1696                 } else if (ctx->stage == MESA_SHADER_VERTEX) {
1697                         assert(instr->intrinsic == nir_intrinsic_store_output);
1698 
1699                         /* We should have been vectorized, though we don't
1700                          * currently check that st_vary is emitted only once
1701                          * per slot (this is relevant, since there's not a mask
1702                          * parameter available on the store [set to 0 by the
1703                          * blob]). We do respect the component by adjusting the
1704                          * swizzle. If this is a constant source, we'll need to
1705                          * emit that explicitly. */
1706 
1707                         emit_explicit_constant(ctx, reg, reg);
1708 
1709                         unsigned dst_component = nir_intrinsic_component(instr);
1710                         unsigned nr_comp = nir_src_num_components(instr->src[0]);
1711 
1712                         midgard_instruction st = m_st_vary_32(reg, offset);
1713                         st.load_store.arg_1 = 0x9E;
1714                         st.load_store.arg_2 = 0x1E;
1715 
1716                         switch (nir_alu_type_get_base_type(nir_intrinsic_src_type(instr))) {
1717                         case nir_type_uint:
1718                         case nir_type_bool:
1719                                 st.op = midgard_op_st_vary_32u;
1720                                 break;
1721                         case nir_type_int:
1722                                 st.op = midgard_op_st_vary_32i;
1723                                 break;
1724                         case nir_type_float:
1725                                 st.op = midgard_op_st_vary_32;
1726                                 break;
1727                         default:
1728                                 unreachable("Attempted to store unknown type");
1729                                 break;
1730                         }
1731 
1732                         /* nir_intrinsic_component(store_intr) encodes the
1733                          * destination component start. Source component offset
1734                          * adjustment is taken care of in
1735                          * install_registers_instr(), when offset_swizzle() is
1736                          * called.
1737                          */
1738                         unsigned src_component = COMPONENT_X;
1739 
1740                         assert(nr_comp > 0);
1741                         for (unsigned i = 0; i < ARRAY_SIZE(st.swizzle); ++i) {
1742                                 st.swizzle[0][i] = src_component;
1743                                 if (i >= dst_component && i < dst_component + nr_comp - 1)
1744                                         src_component++;
1745                         }
1746 
1747                         emit_mir_instruction(ctx, st);
1748                 } else {
1749                         DBG("Unknown store\n");
1750                         assert(0);
1751                 }
1752 
1753                 break;
1754 
1755         /* Special case of store_output for lowered blend shaders */
1756         case nir_intrinsic_store_raw_output_pan:
1757                 assert (ctx->stage == MESA_SHADER_FRAGMENT);
1758                 reg = nir_src_index(ctx, &instr->src[0]);
1759                 emit_fragment_store(ctx, reg, ~0, ~0, ctx->blend_rt);
1760                 break;
1761 
1762         case nir_intrinsic_store_global:
1763         case nir_intrinsic_store_shared:
1764                 reg = nir_src_index(ctx, &instr->src[0]);
1765                 emit_explicit_constant(ctx, reg, reg);
1766 
1767                 emit_global(ctx, &instr->instr, false, reg, &instr->src[1], instr->intrinsic == nir_intrinsic_store_shared);
1768                 break;
1769 
1770         case nir_intrinsic_load_ssbo_address:
1771                 emit_sysval_read(ctx, &instr->instr, 1, 0);
1772                 break;
1773 
1774         case nir_intrinsic_get_ssbo_size:
1775                 emit_sysval_read(ctx, &instr->instr, 1, 8);
1776                 break;
1777 
1778         case nir_intrinsic_load_viewport_scale:
1779         case nir_intrinsic_load_viewport_offset:
1780         case nir_intrinsic_load_num_work_groups:
1781         case nir_intrinsic_load_sampler_lod_parameters_pan:
1782                 emit_sysval_read(ctx, &instr->instr, 3, 0);
1783                 break;
1784 
1785         case nir_intrinsic_load_work_group_id:
1786         case nir_intrinsic_load_local_invocation_id:
1787                 emit_compute_builtin(ctx, instr);
1788                 break;
1789 
1790         case nir_intrinsic_load_vertex_id:
1791         case nir_intrinsic_load_instance_id:
1792                 emit_vertex_builtin(ctx, instr);
1793                 break;
1794 
1795         case nir_intrinsic_load_sample_mask_in:
1796                 emit_special(ctx, instr, 96);
1797                 break;
1798 
1799         case nir_intrinsic_load_sample_id:
1800                 emit_special(ctx, instr, 97);
1801                 break;
1802 
1803         case nir_intrinsic_memory_barrier_buffer:
1804         case nir_intrinsic_memory_barrier_shared:
1805                 break;
1806 
1807         case nir_intrinsic_control_barrier:
1808                 schedule_barrier(ctx);
1809                 emit_control_barrier(ctx);
1810                 schedule_barrier(ctx);
1811                 break;
1812 
1813         ATOMIC_CASE(ctx, instr, add, add);
1814         ATOMIC_CASE(ctx, instr, and, and);
1815         ATOMIC_CASE(ctx, instr, comp_swap, cmpxchg);
1816         ATOMIC_CASE(ctx, instr, exchange, xchg);
1817         ATOMIC_CASE(ctx, instr, imax, imax);
1818         ATOMIC_CASE(ctx, instr, imin, imin);
1819         ATOMIC_CASE(ctx, instr, or, or);
1820         ATOMIC_CASE(ctx, instr, umax, umax);
1821         ATOMIC_CASE(ctx, instr, umin, umin);
1822         ATOMIC_CASE(ctx, instr, xor, xor);
1823 
1824         default:
1825                 fprintf(stderr, "Unhandled intrinsic %s\n", nir_intrinsic_infos[instr->intrinsic].name);
1826                 assert(0);
1827                 break;
1828         }
1829 }
1830 
1831 /* Returns dimension with 0 special casing cubemaps */
1832 static unsigned
midgard_tex_format(enum glsl_sampler_dim dim)1833 midgard_tex_format(enum glsl_sampler_dim dim)
1834 {
1835         switch (dim) {
1836         case GLSL_SAMPLER_DIM_1D:
1837         case GLSL_SAMPLER_DIM_BUF:
1838                 return 1;
1839 
1840         case GLSL_SAMPLER_DIM_2D:
1841         case GLSL_SAMPLER_DIM_MS:
1842         case GLSL_SAMPLER_DIM_EXTERNAL:
1843         case GLSL_SAMPLER_DIM_RECT:
1844                 return 2;
1845 
1846         case GLSL_SAMPLER_DIM_3D:
1847                 return 3;
1848 
1849         case GLSL_SAMPLER_DIM_CUBE:
1850                 return 0;
1851 
1852         default:
1853                 DBG("Unknown sampler dim type\n");
1854                 assert(0);
1855                 return 0;
1856         }
1857 }
1858 
1859 /* Tries to attach an explicit LOD or bias as a constant. Returns whether this
1860  * was successful */
1861 
1862 static bool
pan_attach_constant_bias(compiler_context * ctx,nir_src lod,midgard_texture_word * word)1863 pan_attach_constant_bias(
1864         compiler_context *ctx,
1865         nir_src lod,
1866         midgard_texture_word *word)
1867 {
1868         /* To attach as constant, it has to *be* constant */
1869 
1870         if (!nir_src_is_const(lod))
1871                 return false;
1872 
1873         float f = nir_src_as_float(lod);
1874 
1875         /* Break into fixed-point */
1876         signed lod_int = f;
1877         float lod_frac = f - lod_int;
1878 
1879         /* Carry over negative fractions */
1880         if (lod_frac < 0.0) {
1881                 lod_int--;
1882                 lod_frac += 1.0;
1883         }
1884 
1885         /* Encode */
1886         word->bias = float_to_ubyte(lod_frac);
1887         word->bias_int = lod_int;
1888 
1889         return true;
1890 }
1891 
1892 static enum mali_texture_mode
mdg_texture_mode(nir_tex_instr * instr)1893 mdg_texture_mode(nir_tex_instr *instr)
1894 {
1895         if (instr->op == nir_texop_tg4 && instr->is_shadow)
1896                 return TEXTURE_GATHER_SHADOW;
1897         else if (instr->op == nir_texop_tg4)
1898                 return TEXTURE_GATHER_X + instr->component;
1899         else if (instr->is_shadow)
1900                 return TEXTURE_SHADOW;
1901         else
1902                 return TEXTURE_NORMAL;
1903 }
1904 
1905 static void
emit_texop_native(compiler_context * ctx,nir_tex_instr * instr,unsigned midgard_texop)1906 emit_texop_native(compiler_context *ctx, nir_tex_instr *instr,
1907                   unsigned midgard_texop)
1908 {
1909         /* TODO */
1910         //assert (!instr->sampler);
1911 
1912         nir_dest *dest = &instr->dest;
1913 
1914         int texture_index = instr->texture_index;
1915         int sampler_index = texture_index;
1916 
1917         nir_alu_type dest_base = nir_alu_type_get_base_type(instr->dest_type);
1918         nir_alu_type dest_type = dest_base | nir_dest_bit_size(*dest);
1919 
1920         /* texture instructions support float outmods */
1921         unsigned outmod = midgard_outmod_none;
1922         if (dest_base == nir_type_float) {
1923                 outmod = mir_determine_float_outmod(ctx, &dest, 0);
1924         }
1925 
1926         midgard_instruction ins = {
1927                 .type = TAG_TEXTURE_4,
1928                 .mask = 0xF,
1929                 .dest = nir_dest_index(dest),
1930                 .src = { ~0, ~0, ~0, ~0 },
1931                 .dest_type = dest_type,
1932                 .swizzle = SWIZZLE_IDENTITY_4,
1933                 .outmod = outmod,
1934                 .op = midgard_texop,
1935                 .texture = {
1936                         .format = midgard_tex_format(instr->sampler_dim),
1937                         .texture_handle = texture_index,
1938                         .sampler_handle = sampler_index,
1939                         .mode = mdg_texture_mode(instr)
1940                 }
1941         };
1942 
1943         if (instr->is_shadow && !instr->is_new_style_shadow && instr->op != nir_texop_tg4)
1944            for (int i = 0; i < 4; ++i)
1945               ins.swizzle[0][i] = COMPONENT_X;
1946 
1947         /* We may need a temporary for the coordinate */
1948 
1949         bool needs_temp_coord =
1950                 (midgard_texop == TEXTURE_OP_TEXEL_FETCH) ||
1951                 (instr->sampler_dim == GLSL_SAMPLER_DIM_CUBE) ||
1952                 (instr->is_shadow);
1953 
1954         unsigned coords = needs_temp_coord ? make_compiler_temp_reg(ctx) : 0;
1955 
1956         for (unsigned i = 0; i < instr->num_srcs; ++i) {
1957                 int index = nir_src_index(ctx, &instr->src[i].src);
1958                 unsigned nr_components = nir_src_num_components(instr->src[i].src);
1959                 unsigned sz = nir_src_bit_size(instr->src[i].src);
1960                 nir_alu_type T = nir_tex_instr_src_type(instr, i) | sz;
1961 
1962                 switch (instr->src[i].src_type) {
1963                 case nir_tex_src_coord: {
1964                         emit_explicit_constant(ctx, index, index);
1965 
1966                         unsigned coord_mask = mask_of(instr->coord_components);
1967 
1968                         bool flip_zw = (instr->sampler_dim == GLSL_SAMPLER_DIM_2D) && (coord_mask & (1 << COMPONENT_Z));
1969 
1970                         if (flip_zw)
1971                                 coord_mask ^= ((1 << COMPONENT_Z) | (1 << COMPONENT_W));
1972 
1973                         if (instr->sampler_dim == GLSL_SAMPLER_DIM_CUBE) {
1974                                 /* texelFetch is undefined on samplerCube */
1975                                 assert(midgard_texop != TEXTURE_OP_TEXEL_FETCH);
1976 
1977                                 /* For cubemaps, we use a special ld/st op to
1978                                  * select the face and copy the xy into the
1979                                  * texture register */
1980 
1981                                 midgard_instruction ld = m_ld_cubemap_coords(coords, 0);
1982                                 ld.src[1] = index;
1983                                 ld.src_types[1] = T;
1984                                 ld.mask = 0x3; /* xy */
1985                                 ld.load_store.arg_1 = 0x20;
1986                                 ld.swizzle[1][3] = COMPONENT_X;
1987                                 emit_mir_instruction(ctx, ld);
1988 
1989                                 /* xyzw -> xyxx */
1990                                 ins.swizzle[1][2] = instr->is_shadow ? COMPONENT_Z : COMPONENT_X;
1991                                 ins.swizzle[1][3] = COMPONENT_X;
1992                         } else if (needs_temp_coord) {
1993                                 /* mov coord_temp, coords */
1994                                 midgard_instruction mov = v_mov(index, coords);
1995                                 mov.mask = coord_mask;
1996 
1997                                 if (flip_zw)
1998                                         mov.swizzle[1][COMPONENT_W] = COMPONENT_Z;
1999 
2000                                 emit_mir_instruction(ctx, mov);
2001                         } else {
2002                                 coords = index;
2003                         }
2004 
2005                         ins.src[1] = coords;
2006                         ins.src_types[1] = T;
2007 
2008                         /* Texelfetch coordinates uses all four elements
2009                          * (xyz/index) regardless of texture dimensionality,
2010                          * which means it's necessary to zero the unused
2011                          * components to keep everything happy */
2012 
2013                         if (midgard_texop == TEXTURE_OP_TEXEL_FETCH) {
2014                                 /* mov index.zw, #0, or generalized */
2015                                 midgard_instruction mov =
2016                                         v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT), coords);
2017                                 mov.has_constants = true;
2018                                 mov.mask = coord_mask ^ 0xF;
2019                                 emit_mir_instruction(ctx, mov);
2020                         }
2021 
2022                         if (instr->sampler_dim == GLSL_SAMPLER_DIM_2D) {
2023                                 /* Array component in w but NIR wants it in z,
2024                                  * but if we have a temp coord we already fixed
2025                                  * that up */
2026 
2027                                 if (nr_components == 3) {
2028                                         ins.swizzle[1][2] = COMPONENT_Z;
2029                                         ins.swizzle[1][3] = needs_temp_coord ? COMPONENT_W : COMPONENT_Z;
2030                                 } else if (nr_components == 2) {
2031                                         ins.swizzle[1][2] =
2032                                                 instr->is_shadow ? COMPONENT_Z : COMPONENT_X;
2033                                         ins.swizzle[1][3] = COMPONENT_X;
2034                                 } else
2035                                         unreachable("Invalid texture 2D components");
2036                         }
2037 
2038                         if (midgard_texop == TEXTURE_OP_TEXEL_FETCH) {
2039                                 /* We zeroed */
2040                                 ins.swizzle[1][2] = COMPONENT_Z;
2041                                 ins.swizzle[1][3] = COMPONENT_W;
2042                         }
2043 
2044                         break;
2045                 }
2046 
2047                 case nir_tex_src_bias:
2048                 case nir_tex_src_lod: {
2049                         /* Try as a constant if we can */
2050 
2051                         bool is_txf = midgard_texop == TEXTURE_OP_TEXEL_FETCH;
2052                         if (!is_txf && pan_attach_constant_bias(ctx, instr->src[i].src, &ins.texture))
2053                                 break;
2054 
2055                         ins.texture.lod_register = true;
2056                         ins.src[2] = index;
2057                         ins.src_types[2] = T;
2058 
2059                         for (unsigned c = 0; c < MIR_VEC_COMPONENTS; ++c)
2060                                 ins.swizzle[2][c] = COMPONENT_X;
2061 
2062                         emit_explicit_constant(ctx, index, index);
2063 
2064                         break;
2065                 };
2066 
2067                 case nir_tex_src_offset: {
2068                         ins.texture.offset_register = true;
2069                         ins.src[3] = index;
2070                         ins.src_types[3] = T;
2071 
2072                         for (unsigned c = 0; c < MIR_VEC_COMPONENTS; ++c)
2073                                 ins.swizzle[3][c] = (c > COMPONENT_Z) ? 0 : c;
2074 
2075                         emit_explicit_constant(ctx, index, index);
2076                         break;
2077                 };
2078 
2079                 case nir_tex_src_comparator:
2080                 case nir_tex_src_ms_index: {
2081                         unsigned comp = COMPONENT_Z;
2082 
2083                         /* mov coord_temp.foo, coords */
2084                         midgard_instruction mov = v_mov(index, coords);
2085                         mov.mask = 1 << comp;
2086 
2087                         for (unsigned i = 0; i < MIR_VEC_COMPONENTS; ++i)
2088                                 mov.swizzle[1][i] = COMPONENT_X;
2089 
2090                         emit_mir_instruction(ctx, mov);
2091                         break;
2092                 }
2093 
2094                 default: {
2095                         fprintf(stderr, "Unknown texture source type: %d\n", instr->src[i].src_type);
2096                         assert(0);
2097                 }
2098                 }
2099         }
2100 
2101         emit_mir_instruction(ctx, ins);
2102 }
2103 
2104 static void
emit_tex(compiler_context * ctx,nir_tex_instr * instr)2105 emit_tex(compiler_context *ctx, nir_tex_instr *instr)
2106 {
2107         switch (instr->op) {
2108         case nir_texop_tex:
2109         case nir_texop_txb:
2110                 emit_texop_native(ctx, instr, TEXTURE_OP_NORMAL);
2111                 break;
2112         case nir_texop_txl:
2113         case nir_texop_tg4:
2114                 emit_texop_native(ctx, instr, TEXTURE_OP_LOD);
2115                 break;
2116         case nir_texop_txf:
2117         case nir_texop_txf_ms:
2118                 emit_texop_native(ctx, instr, TEXTURE_OP_TEXEL_FETCH);
2119                 break;
2120         case nir_texop_txs:
2121                 emit_sysval_read(ctx, &instr->instr, 4, 0);
2122                 break;
2123         default: {
2124                 fprintf(stderr, "Unhandled texture op: %d\n", instr->op);
2125                 assert(0);
2126         }
2127         }
2128 }
2129 
2130 static void
emit_jump(compiler_context * ctx,nir_jump_instr * instr)2131 emit_jump(compiler_context *ctx, nir_jump_instr *instr)
2132 {
2133         switch (instr->type) {
2134         case nir_jump_break: {
2135                 /* Emit a branch out of the loop */
2136                 struct midgard_instruction br = v_branch(false, false);
2137                 br.branch.target_type = TARGET_BREAK;
2138                 br.branch.target_break = ctx->current_loop_depth;
2139                 emit_mir_instruction(ctx, br);
2140                 break;
2141         }
2142 
2143         default:
2144                 DBG("Unknown jump type %d\n", instr->type);
2145                 break;
2146         }
2147 }
2148 
2149 static void
emit_instr(compiler_context * ctx,struct nir_instr * instr)2150 emit_instr(compiler_context *ctx, struct nir_instr *instr)
2151 {
2152         switch (instr->type) {
2153         case nir_instr_type_load_const:
2154                 emit_load_const(ctx, nir_instr_as_load_const(instr));
2155                 break;
2156 
2157         case nir_instr_type_intrinsic:
2158                 emit_intrinsic(ctx, nir_instr_as_intrinsic(instr));
2159                 break;
2160 
2161         case nir_instr_type_alu:
2162                 emit_alu(ctx, nir_instr_as_alu(instr));
2163                 break;
2164 
2165         case nir_instr_type_tex:
2166                 emit_tex(ctx, nir_instr_as_tex(instr));
2167                 break;
2168 
2169         case nir_instr_type_jump:
2170                 emit_jump(ctx, nir_instr_as_jump(instr));
2171                 break;
2172 
2173         case nir_instr_type_ssa_undef:
2174                 /* Spurious */
2175                 break;
2176 
2177         default:
2178                 DBG("Unhandled instruction type\n");
2179                 break;
2180         }
2181 }
2182 
2183 
2184 /* ALU instructions can inline or embed constants, which decreases register
2185  * pressure and saves space. */
2186 
2187 #define CONDITIONAL_ATTACH(idx) { \
2188 	void *entry = _mesa_hash_table_u64_search(ctx->ssa_constants, alu->src[idx] + 1); \
2189 \
2190 	if (entry) { \
2191 		attach_constants(ctx, alu, entry, alu->src[idx] + 1); \
2192 		alu->src[idx] = SSA_FIXED_REGISTER(REGISTER_CONSTANT); \
2193 	} \
2194 }
2195 
2196 static void
inline_alu_constants(compiler_context * ctx,midgard_block * block)2197 inline_alu_constants(compiler_context *ctx, midgard_block *block)
2198 {
2199         mir_foreach_instr_in_block(block, alu) {
2200                 /* Other instructions cannot inline constants */
2201                 if (alu->type != TAG_ALU_4) continue;
2202                 if (alu->compact_branch) continue;
2203 
2204                 /* If there is already a constant here, we can do nothing */
2205                 if (alu->has_constants) continue;
2206 
2207                 CONDITIONAL_ATTACH(0);
2208 
2209                 if (!alu->has_constants) {
2210                         CONDITIONAL_ATTACH(1)
2211                 } else if (!alu->inline_constant) {
2212                         /* Corner case: _two_ vec4 constants, for instance with a
2213                          * csel. For this case, we can only use a constant
2214                          * register for one, we'll have to emit a move for the
2215                          * other. */
2216 
2217                         void *entry = _mesa_hash_table_u64_search(ctx->ssa_constants, alu->src[1] + 1);
2218                         unsigned scratch = make_compiler_temp(ctx);
2219 
2220                         if (entry) {
2221                                 midgard_instruction ins = v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT), scratch);
2222                                 attach_constants(ctx, &ins, entry, alu->src[1] + 1);
2223 
2224                                 /* Set the source */
2225                                 alu->src[1] = scratch;
2226 
2227                                 /* Inject us -before- the last instruction which set r31 */
2228                                 mir_insert_instruction_before(ctx, mir_prev_op(alu), ins);
2229                         }
2230                 }
2231         }
2232 }
2233 
2234 unsigned
max_bitsize_for_alu(midgard_instruction * ins)2235 max_bitsize_for_alu(midgard_instruction *ins)
2236 {
2237         unsigned max_bitsize = 0;
2238         for (int i = 0; i < MIR_SRC_COUNT; i++) {
2239                 if (ins->src[i] == ~0) continue;
2240                 unsigned src_bitsize = nir_alu_type_get_type_size(ins->src_types[i]);
2241                 max_bitsize = MAX2(src_bitsize, max_bitsize);
2242         }
2243         unsigned dst_bitsize = nir_alu_type_get_type_size(ins->dest_type);
2244         max_bitsize = MAX2(dst_bitsize, max_bitsize);
2245 
2246         /* We don't have fp16 LUTs, so we'll want to emit code like:
2247          *
2248          *      vlut.fsinr hr0, hr0
2249          *
2250          * where both input and output are 16-bit but the operation is carried
2251          * out in 32-bit
2252          */
2253 
2254         switch (ins->op) {
2255         case midgard_alu_op_fsqrt:
2256         case midgard_alu_op_frcp:
2257         case midgard_alu_op_frsqrt:
2258         case midgard_alu_op_fsin:
2259         case midgard_alu_op_fcos:
2260         case midgard_alu_op_fexp2:
2261         case midgard_alu_op_flog2:
2262                 max_bitsize = MAX2(max_bitsize, 32);
2263                 break;
2264 
2265         default:
2266                 break;
2267         }
2268 
2269         /* High implies computing at a higher bitsize, e.g umul_high of 32-bit
2270          * requires computing at 64-bit */
2271         if (midgard_is_integer_out_op(ins->op) && ins->outmod == midgard_outmod_int_high) {
2272                 max_bitsize *= 2;
2273                 assert(max_bitsize <= 64);
2274         }
2275 
2276         return max_bitsize;
2277 }
2278 
2279 midgard_reg_mode
reg_mode_for_bitsize(unsigned bitsize)2280 reg_mode_for_bitsize(unsigned bitsize)
2281 {
2282         switch (bitsize) {
2283                 /* use 16 pipe for 8 since we don't support vec16 yet */
2284         case 8:
2285         case 16:
2286                 return midgard_reg_mode_16;
2287         case 32:
2288                 return midgard_reg_mode_32;
2289         case 64:
2290                 return midgard_reg_mode_64;
2291         default:
2292                 unreachable("invalid bit size");
2293         }
2294 }
2295 
2296 /* Midgard supports two types of constants, embedded constants (128-bit) and
2297  * inline constants (16-bit). Sometimes, especially with scalar ops, embedded
2298  * constants can be demoted to inline constants, for space savings and
2299  * sometimes a performance boost */
2300 
2301 static void
embedded_to_inline_constant(compiler_context * ctx,midgard_block * block)2302 embedded_to_inline_constant(compiler_context *ctx, midgard_block *block)
2303 {
2304         mir_foreach_instr_in_block(block, ins) {
2305                 if (!ins->has_constants) continue;
2306                 if (ins->has_inline_constant) continue;
2307 
2308                 unsigned max_bitsize = max_bitsize_for_alu(ins);
2309 
2310                 /* We can inline 32-bit (sometimes) or 16-bit (usually) */
2311                 bool is_16 = max_bitsize == 16;
2312                 bool is_32 = max_bitsize == 32;
2313 
2314                 if (!(is_16 || is_32))
2315                         continue;
2316 
2317                 /* src1 cannot be an inline constant due to encoding
2318                  * restrictions. So, if possible we try to flip the arguments
2319                  * in that case */
2320 
2321                 int op = ins->op;
2322 
2323                 if (ins->src[0] == SSA_FIXED_REGISTER(REGISTER_CONSTANT) &&
2324                                 alu_opcode_props[op].props & OP_COMMUTES) {
2325                         mir_flip(ins);
2326                 }
2327 
2328                 if (ins->src[1] == SSA_FIXED_REGISTER(REGISTER_CONSTANT)) {
2329                         /* Component is from the swizzle. Take a nonzero component */
2330                         assert(ins->mask);
2331                         unsigned first_comp = ffs(ins->mask) - 1;
2332                         unsigned component = ins->swizzle[1][first_comp];
2333 
2334                         /* Scale constant appropriately, if we can legally */
2335                         int16_t scaled_constant = 0;
2336 
2337                         if (is_16) {
2338                                 scaled_constant = ins->constants.u16[component];
2339                         } else if (midgard_is_integer_op(op)) {
2340                                 scaled_constant = ins->constants.u32[component];
2341 
2342                                 /* Constant overflow after resize */
2343                                 if (scaled_constant != ins->constants.u32[component])
2344                                         continue;
2345                         } else {
2346                                 float original = ins->constants.f32[component];
2347                                 scaled_constant = _mesa_float_to_half(original);
2348 
2349                                 /* Check for loss of precision. If this is
2350                                  * mediump, we don't care, but for a highp
2351                                  * shader, we need to pay attention. NIR
2352                                  * doesn't yet tell us which mode we're in!
2353                                  * Practically this prevents most constants
2354                                  * from being inlined, sadly. */
2355 
2356                                 float fp32 = _mesa_half_to_float(scaled_constant);
2357 
2358                                 if (fp32 != original)
2359                                         continue;
2360                         }
2361 
2362                         /* Should've been const folded */
2363                         if (ins->src_abs[1] || ins->src_neg[1])
2364                                 continue;
2365 
2366                         /* Make sure that the constant is not itself a vector
2367                          * by checking if all accessed values are the same. */
2368 
2369                         const midgard_constants *cons = &ins->constants;
2370                         uint32_t value = is_16 ? cons->u16[component] : cons->u32[component];
2371 
2372                         bool is_vector = false;
2373                         unsigned mask = effective_writemask(ins->op, ins->mask);
2374 
2375                         for (unsigned c = 0; c < MIR_VEC_COMPONENTS; ++c) {
2376                                 /* We only care if this component is actually used */
2377                                 if (!(mask & (1 << c)))
2378                                         continue;
2379 
2380                                 uint32_t test = is_16 ?
2381                                                 cons->u16[ins->swizzle[1][c]] :
2382                                                 cons->u32[ins->swizzle[1][c]];
2383 
2384                                 if (test != value) {
2385                                         is_vector = true;
2386                                         break;
2387                                 }
2388                         }
2389 
2390                         if (is_vector)
2391                                 continue;
2392 
2393                         /* Get rid of the embedded constant */
2394                         ins->has_constants = false;
2395                         ins->src[1] = ~0;
2396                         ins->has_inline_constant = true;
2397                         ins->inline_constant = scaled_constant;
2398                 }
2399         }
2400 }
2401 
2402 /* Dead code elimination for branches at the end of a block - only one branch
2403  * per block is legal semantically */
2404 
2405 static void
midgard_cull_dead_branch(compiler_context * ctx,midgard_block * block)2406 midgard_cull_dead_branch(compiler_context *ctx, midgard_block *block)
2407 {
2408         bool branched = false;
2409 
2410         mir_foreach_instr_in_block_safe(block, ins) {
2411                 if (!midgard_is_branch_unit(ins->unit)) continue;
2412 
2413                 if (branched)
2414                         mir_remove_instruction(ins);
2415 
2416                 branched = true;
2417         }
2418 }
2419 
2420 /* We want to force the invert on AND/OR to the second slot to legalize into
2421  * iandnot/iornot. The relevant patterns are for AND (and OR respectively)
2422  *
2423  *   ~a & #b = ~a & ~(#~b)
2424  *   ~a & b = b & ~a
2425  */
2426 
2427 static void
midgard_legalize_invert(compiler_context * ctx,midgard_block * block)2428 midgard_legalize_invert(compiler_context *ctx, midgard_block *block)
2429 {
2430         mir_foreach_instr_in_block(block, ins) {
2431                 if (ins->type != TAG_ALU_4) continue;
2432 
2433                 if (ins->op != midgard_alu_op_iand &&
2434                     ins->op != midgard_alu_op_ior) continue;
2435 
2436                 if (ins->src_invert[1] || !ins->src_invert[0]) continue;
2437 
2438                 if (ins->has_inline_constant) {
2439                         /* ~(#~a) = ~(~#a) = a, so valid, and forces both
2440                          * inverts on */
2441                         ins->inline_constant = ~ins->inline_constant;
2442                         ins->src_invert[1] = true;
2443                 } else {
2444                         /* Flip to the right invert order. Note
2445                          * has_inline_constant false by assumption on the
2446                          * branch, so flipping makes sense. */
2447                         mir_flip(ins);
2448                 }
2449         }
2450 }
2451 
2452 static unsigned
emit_fragment_epilogue(compiler_context * ctx,unsigned rt)2453 emit_fragment_epilogue(compiler_context *ctx, unsigned rt)
2454 {
2455         /* Loop to ourselves */
2456         midgard_instruction *br = ctx->writeout_branch[rt];
2457         struct midgard_instruction ins = v_branch(false, false);
2458         ins.writeout = br->writeout;
2459         ins.branch.target_block = ctx->block_count - 1;
2460         ins.constants.u32[0] = br->constants.u32[0];
2461         memcpy(&ins.src_types, &br->src_types, sizeof(ins.src_types));
2462         emit_mir_instruction(ctx, ins);
2463 
2464         ctx->current_block->epilogue = true;
2465         schedule_barrier(ctx);
2466         return ins.branch.target_block;
2467 }
2468 
2469 static midgard_block *
emit_block_init(compiler_context * ctx)2470 emit_block_init(compiler_context *ctx)
2471 {
2472         midgard_block *this_block = ctx->after_block;
2473         ctx->after_block = NULL;
2474 
2475         if (!this_block)
2476                 this_block = create_empty_block(ctx);
2477 
2478         list_addtail(&this_block->base.link, &ctx->blocks);
2479 
2480         this_block->scheduled = false;
2481         ++ctx->block_count;
2482 
2483         /* Set up current block */
2484         list_inithead(&this_block->base.instructions);
2485         ctx->current_block = this_block;
2486 
2487         return this_block;
2488 }
2489 
2490 static midgard_block *
emit_block(compiler_context * ctx,nir_block * block)2491 emit_block(compiler_context *ctx, nir_block *block)
2492 {
2493         midgard_block *this_block = emit_block_init(ctx);
2494 
2495         nir_foreach_instr(instr, block) {
2496                 emit_instr(ctx, instr);
2497                 ++ctx->instruction_count;
2498         }
2499 
2500         return this_block;
2501 }
2502 
2503 static midgard_block *emit_cf_list(struct compiler_context *ctx, struct exec_list *list);
2504 
2505 static void
emit_if(struct compiler_context * ctx,nir_if * nif)2506 emit_if(struct compiler_context *ctx, nir_if *nif)
2507 {
2508         midgard_block *before_block = ctx->current_block;
2509 
2510         /* Speculatively emit the branch, but we can't fill it in until later */
2511         bool inv = false;
2512         EMIT(branch, true, true);
2513         midgard_instruction *then_branch = mir_last_in_block(ctx->current_block);
2514         then_branch->src[0] = mir_get_branch_cond(&nif->condition, &inv);
2515         then_branch->src_types[0] = nir_type_uint32;
2516         then_branch->branch.invert_conditional = !inv;
2517 
2518         /* Emit the two subblocks. */
2519         midgard_block *then_block = emit_cf_list(ctx, &nif->then_list);
2520         midgard_block *end_then_block = ctx->current_block;
2521 
2522         /* Emit a jump from the end of the then block to the end of the else */
2523         EMIT(branch, false, false);
2524         midgard_instruction *then_exit = mir_last_in_block(ctx->current_block);
2525 
2526         /* Emit second block, and check if it's empty */
2527 
2528         int else_idx = ctx->block_count;
2529         int count_in = ctx->instruction_count;
2530         midgard_block *else_block = emit_cf_list(ctx, &nif->else_list);
2531         midgard_block *end_else_block = ctx->current_block;
2532         int after_else_idx = ctx->block_count;
2533 
2534         /* Now that we have the subblocks emitted, fix up the branches */
2535 
2536         assert(then_block);
2537         assert(else_block);
2538 
2539         if (ctx->instruction_count == count_in) {
2540                 /* The else block is empty, so don't emit an exit jump */
2541                 mir_remove_instruction(then_exit);
2542                 then_branch->branch.target_block = after_else_idx;
2543         } else {
2544                 then_branch->branch.target_block = else_idx;
2545                 then_exit->branch.target_block = after_else_idx;
2546         }
2547 
2548         /* Wire up the successors */
2549 
2550         ctx->after_block = create_empty_block(ctx);
2551 
2552         pan_block_add_successor(&before_block->base, &then_block->base);
2553         pan_block_add_successor(&before_block->base, &else_block->base);
2554 
2555         pan_block_add_successor(&end_then_block->base, &ctx->after_block->base);
2556         pan_block_add_successor(&end_else_block->base, &ctx->after_block->base);
2557 }
2558 
2559 static void
emit_loop(struct compiler_context * ctx,nir_loop * nloop)2560 emit_loop(struct compiler_context *ctx, nir_loop *nloop)
2561 {
2562         /* Remember where we are */
2563         midgard_block *start_block = ctx->current_block;
2564 
2565         /* Allocate a loop number, growing the current inner loop depth */
2566         int loop_idx = ++ctx->current_loop_depth;
2567 
2568         /* Get index from before the body so we can loop back later */
2569         int start_idx = ctx->block_count;
2570 
2571         /* Emit the body itself */
2572         midgard_block *loop_block = emit_cf_list(ctx, &nloop->body);
2573 
2574         /* Branch back to loop back */
2575         struct midgard_instruction br_back = v_branch(false, false);
2576         br_back.branch.target_block = start_idx;
2577         emit_mir_instruction(ctx, br_back);
2578 
2579         /* Mark down that branch in the graph. */
2580         pan_block_add_successor(&start_block->base, &loop_block->base);
2581         pan_block_add_successor(&ctx->current_block->base, &loop_block->base);
2582 
2583         /* Find the index of the block about to follow us (note: we don't add
2584          * one; blocks are 0-indexed so we get a fencepost problem) */
2585         int break_block_idx = ctx->block_count;
2586 
2587         /* Fix up the break statements we emitted to point to the right place,
2588          * now that we can allocate a block number for them */
2589         ctx->after_block = create_empty_block(ctx);
2590 
2591         mir_foreach_block_from(ctx, start_block, _block) {
2592                 mir_foreach_instr_in_block(((midgard_block *) _block), ins) {
2593                         if (ins->type != TAG_ALU_4) continue;
2594                         if (!ins->compact_branch) continue;
2595 
2596                         /* We found a branch -- check the type to see if we need to do anything */
2597                         if (ins->branch.target_type != TARGET_BREAK) continue;
2598 
2599                         /* It's a break! Check if it's our break */
2600                         if (ins->branch.target_break != loop_idx) continue;
2601 
2602                         /* Okay, cool, we're breaking out of this loop.
2603                          * Rewrite from a break to a goto */
2604 
2605                         ins->branch.target_type = TARGET_GOTO;
2606                         ins->branch.target_block = break_block_idx;
2607 
2608                         pan_block_add_successor(_block, &ctx->after_block->base);
2609                 }
2610         }
2611 
2612         /* Now that we've finished emitting the loop, free up the depth again
2613          * so we play nice with recursion amid nested loops */
2614         --ctx->current_loop_depth;
2615 
2616         /* Dump loop stats */
2617         ++ctx->loop_count;
2618 }
2619 
2620 static midgard_block *
emit_cf_list(struct compiler_context * ctx,struct exec_list * list)2621 emit_cf_list(struct compiler_context *ctx, struct exec_list *list)
2622 {
2623         midgard_block *start_block = NULL;
2624 
2625         foreach_list_typed(nir_cf_node, node, node, list) {
2626                 switch (node->type) {
2627                 case nir_cf_node_block: {
2628                         midgard_block *block = emit_block(ctx, nir_cf_node_as_block(node));
2629 
2630                         if (!start_block)
2631                                 start_block = block;
2632 
2633                         break;
2634                 }
2635 
2636                 case nir_cf_node_if:
2637                         emit_if(ctx, nir_cf_node_as_if(node));
2638                         break;
2639 
2640                 case nir_cf_node_loop:
2641                         emit_loop(ctx, nir_cf_node_as_loop(node));
2642                         break;
2643 
2644                 case nir_cf_node_function:
2645                         assert(0);
2646                         break;
2647                 }
2648         }
2649 
2650         return start_block;
2651 }
2652 
2653 /* Due to lookahead, we need to report the first tag executed in the command
2654  * stream and in branch targets. An initial block might be empty, so iterate
2655  * until we find one that 'works' */
2656 
2657 unsigned
midgard_get_first_tag_from_block(compiler_context * ctx,unsigned block_idx)2658 midgard_get_first_tag_from_block(compiler_context *ctx, unsigned block_idx)
2659 {
2660         midgard_block *initial_block = mir_get_block(ctx, block_idx);
2661 
2662         mir_foreach_block_from(ctx, initial_block, _v) {
2663                 midgard_block *v = (midgard_block *) _v;
2664                 if (v->quadword_count) {
2665                         midgard_bundle *initial_bundle =
2666                                 util_dynarray_element(&v->bundles, midgard_bundle, 0);
2667 
2668                         return initial_bundle->tag;
2669                 }
2670         }
2671 
2672         /* Default to a tag 1 which will break from the shader, in case we jump
2673          * to the exit block (i.e. `return` in a compute shader) */
2674 
2675         return 1;
2676 }
2677 
2678 /* For each fragment writeout instruction, generate a writeout loop to
2679  * associate with it */
2680 
2681 static void
mir_add_writeout_loops(compiler_context * ctx)2682 mir_add_writeout_loops(compiler_context *ctx)
2683 {
2684         for (unsigned rt = 0; rt < ARRAY_SIZE(ctx->writeout_branch); ++rt) {
2685                 midgard_instruction *br = ctx->writeout_branch[rt];
2686                 if (!br) continue;
2687 
2688                 unsigned popped = br->branch.target_block;
2689                 pan_block_add_successor(&(mir_get_block(ctx, popped - 1)->base), &ctx->current_block->base);
2690                 br->branch.target_block = emit_fragment_epilogue(ctx, rt);
2691                 br->branch.target_type = TARGET_GOTO;
2692 
2693                 /* If we have more RTs, we'll need to restore back after our
2694                  * loop terminates */
2695 
2696                 if ((rt + 1) < ARRAY_SIZE(ctx->writeout_branch) && ctx->writeout_branch[rt + 1]) {
2697                         midgard_instruction uncond = v_branch(false, false);
2698                         uncond.branch.target_block = popped;
2699                         uncond.branch.target_type = TARGET_GOTO;
2700                         emit_mir_instruction(ctx, uncond);
2701                         pan_block_add_successor(&ctx->current_block->base, &(mir_get_block(ctx, popped)->base));
2702                         schedule_barrier(ctx);
2703                 } else {
2704                         /* We're last, so we can terminate here */
2705                         br->last_writeout = true;
2706                 }
2707         }
2708 }
2709 
2710 panfrost_program *
midgard_compile_shader_nir(void * mem_ctx,nir_shader * nir,const struct panfrost_compile_inputs * inputs)2711 midgard_compile_shader_nir(void *mem_ctx, nir_shader *nir,
2712                            const struct panfrost_compile_inputs *inputs)
2713 {
2714         panfrost_program *program = rzalloc(mem_ctx, panfrost_program);
2715 
2716         struct util_dynarray *compiled = &program->compiled;
2717 
2718         midgard_debug = debug_get_option_midgard_debug();
2719 
2720         /* TODO: Bound against what? */
2721         compiler_context *ctx = rzalloc(NULL, compiler_context);
2722 
2723         ctx->nir = nir;
2724         ctx->stage = nir->info.stage;
2725         ctx->is_blend = inputs->is_blend;
2726         ctx->blend_rt = MIDGARD_COLOR_RT0 + inputs->blend.rt;
2727         memcpy(ctx->blend_constants, inputs->blend.constants, sizeof(ctx->blend_constants));
2728         ctx->blend_input = ~0;
2729         ctx->blend_src1 = ~0;
2730         ctx->quirks = midgard_get_quirks(inputs->gpu_id);
2731 
2732         /* Start off with a safe cutoff, allowing usage of all 16 work
2733          * registers. Later, we'll promote uniform reads to uniform registers
2734          * if we determine it is beneficial to do so */
2735         ctx->uniform_cutoff = 8;
2736 
2737         /* Initialize at a global (not block) level hash tables */
2738 
2739         ctx->ssa_constants = _mesa_hash_table_u64_create(NULL);
2740 
2741         /* Lower gl_Position pre-optimisation, but after lowering vars to ssa
2742          * (so we don't accidentally duplicate the epilogue since mesa/st has
2743          * messed with our I/O quite a bit already) */
2744 
2745         NIR_PASS_V(nir, nir_lower_vars_to_ssa);
2746 
2747         if (ctx->stage == MESA_SHADER_VERTEX) {
2748                 NIR_PASS_V(nir, nir_lower_viewport_transform);
2749                 NIR_PASS_V(nir, nir_lower_point_size, 1.0, 1024.0);
2750         }
2751 
2752         NIR_PASS_V(nir, nir_lower_var_copies);
2753         NIR_PASS_V(nir, nir_lower_vars_to_ssa);
2754         NIR_PASS_V(nir, nir_split_var_copies);
2755         NIR_PASS_V(nir, nir_lower_var_copies);
2756         NIR_PASS_V(nir, nir_lower_global_vars_to_local);
2757         NIR_PASS_V(nir, nir_lower_var_copies);
2758         NIR_PASS_V(nir, nir_lower_vars_to_ssa);
2759 
2760         unsigned pan_quirks = panfrost_get_quirks(inputs->gpu_id);
2761         NIR_PASS_V(nir, pan_lower_framebuffer,
2762                    inputs->rt_formats, inputs->is_blend, pan_quirks);
2763 
2764         NIR_PASS_V(nir, nir_lower_io, nir_var_shader_in | nir_var_shader_out,
2765                         glsl_type_size, 0);
2766         NIR_PASS_V(nir, nir_lower_ssbo);
2767         NIR_PASS_V(nir, pan_nir_lower_zs_store);
2768 
2769         /* Optimisation passes */
2770 
2771         optimise_nir(nir, ctx->quirks, inputs->is_blend);
2772 
2773         NIR_PASS_V(nir, pan_nir_reorder_writeout);
2774 
2775         if ((midgard_debug & MIDGARD_DBG_SHADERS) && !nir->info.internal) {
2776                 nir_print_shader(nir, stdout);
2777         }
2778 
2779         /* Assign sysvals and counts, now that we're sure
2780          * (post-optimisation) */
2781 
2782         panfrost_nir_assign_sysvals(&ctx->sysvals, ctx, nir);
2783         program->sysval_count = ctx->sysvals.sysval_count;
2784         memcpy(program->sysvals, ctx->sysvals.sysvals, sizeof(ctx->sysvals.sysvals[0]) * ctx->sysvals.sysval_count);
2785 
2786         nir_foreach_function(func, nir) {
2787                 if (!func->impl)
2788                         continue;
2789 
2790                 list_inithead(&ctx->blocks);
2791                 ctx->block_count = 0;
2792                 ctx->func = func;
2793                 ctx->already_emitted = calloc(BITSET_WORDS(func->impl->ssa_alloc), sizeof(BITSET_WORD));
2794 
2795                 if (nir->info.outputs_read && !inputs->is_blend) {
2796                         emit_block_init(ctx);
2797 
2798                         struct midgard_instruction wait = v_branch(false, false);
2799                         wait.branch.target_type = TARGET_TILEBUF_WAIT;
2800 
2801                         emit_mir_instruction(ctx, wait);
2802 
2803                         ++ctx->instruction_count;
2804                 }
2805 
2806                 emit_cf_list(ctx, &func->impl->body);
2807                 free(ctx->already_emitted);
2808                 break; /* TODO: Multi-function shaders */
2809         }
2810 
2811         util_dynarray_init(compiled, program);
2812 
2813         /* Per-block lowering before opts */
2814 
2815         mir_foreach_block(ctx, _block) {
2816                 midgard_block *block = (midgard_block *) _block;
2817                 inline_alu_constants(ctx, block);
2818                 embedded_to_inline_constant(ctx, block);
2819         }
2820         /* MIR-level optimizations */
2821 
2822         bool progress = false;
2823 
2824         do {
2825                 progress = false;
2826                 progress |= midgard_opt_dead_code_eliminate(ctx);
2827 
2828                 mir_foreach_block(ctx, _block) {
2829                         midgard_block *block = (midgard_block *) _block;
2830                         progress |= midgard_opt_copy_prop(ctx, block);
2831                         progress |= midgard_opt_combine_projection(ctx, block);
2832                         progress |= midgard_opt_varying_projection(ctx, block);
2833                 }
2834         } while (progress);
2835 
2836         mir_foreach_block(ctx, _block) {
2837                 midgard_block *block = (midgard_block *) _block;
2838                 midgard_lower_derivatives(ctx, block);
2839                 midgard_legalize_invert(ctx, block);
2840                 midgard_cull_dead_branch(ctx, block);
2841         }
2842 
2843         if (ctx->stage == MESA_SHADER_FRAGMENT)
2844                 mir_add_writeout_loops(ctx);
2845 
2846         /* Analyze now that the code is known but before scheduling creates
2847          * pipeline registers which are harder to track */
2848         mir_analyze_helper_terminate(ctx);
2849         mir_analyze_helper_requirements(ctx);
2850 
2851         /* Schedule! */
2852         midgard_schedule_program(ctx);
2853         mir_ra(ctx);
2854 
2855         /* Emit flat binary from the instruction arrays. Iterate each block in
2856          * sequence. Save instruction boundaries such that lookahead tags can
2857          * be assigned easily */
2858 
2859         /* Cache _all_ bundles in source order for lookahead across failed branches */
2860 
2861         int bundle_count = 0;
2862         mir_foreach_block(ctx, _block) {
2863                 midgard_block *block = (midgard_block *) _block;
2864                 bundle_count += block->bundles.size / sizeof(midgard_bundle);
2865         }
2866         midgard_bundle **source_order_bundles = malloc(sizeof(midgard_bundle *) * bundle_count);
2867         int bundle_idx = 0;
2868         mir_foreach_block(ctx, _block) {
2869                 midgard_block *block = (midgard_block *) _block;
2870                 util_dynarray_foreach(&block->bundles, midgard_bundle, bundle) {
2871                         source_order_bundles[bundle_idx++] = bundle;
2872                 }
2873         }
2874 
2875         int current_bundle = 0;
2876 
2877         /* Midgard prefetches instruction types, so during emission we
2878          * need to lookahead. Unless this is the last instruction, in
2879          * which we return 1. */
2880 
2881         mir_foreach_block(ctx, _block) {
2882                 midgard_block *block = (midgard_block *) _block;
2883                 mir_foreach_bundle_in_block(block, bundle) {
2884                         int lookahead = 1;
2885 
2886                         if (!bundle->last_writeout && (current_bundle + 1 < bundle_count))
2887                                 lookahead = source_order_bundles[current_bundle + 1]->tag;
2888 
2889                         emit_binary_bundle(ctx, block, bundle, compiled, lookahead);
2890                         ++current_bundle;
2891                 }
2892 
2893                 /* TODO: Free deeper */
2894                 //util_dynarray_fini(&block->instructions);
2895         }
2896 
2897         free(source_order_bundles);
2898 
2899         /* Report the very first tag executed */
2900         program->first_tag = midgard_get_first_tag_from_block(ctx, 0);
2901 
2902         /* Deal with off-by-one related to the fencepost problem */
2903         program->work_register_count = ctx->work_registers + 1;
2904         program->uniform_cutoff = ctx->uniform_cutoff;
2905 
2906         program->tls_size = ctx->tls_size;
2907 
2908         if ((midgard_debug & MIDGARD_DBG_SHADERS) && !nir->info.internal) {
2909                 disassemble_midgard(stdout,
2910                                     program->compiled.data,
2911                                     program->compiled.size,
2912                                     inputs->gpu_id, ctx->stage);
2913         }
2914 
2915         if ((midgard_debug & MIDGARD_DBG_SHADERDB || inputs->shaderdb) &&
2916             !nir->info.internal) {
2917                 unsigned nr_bundles = 0, nr_ins = 0;
2918 
2919                 /* Count instructions and bundles */
2920 
2921                 mir_foreach_block(ctx, _block) {
2922                         midgard_block *block = (midgard_block *) _block;
2923                         nr_bundles += util_dynarray_num_elements(
2924                                               &block->bundles, midgard_bundle);
2925 
2926                         mir_foreach_bundle_in_block(block, bun)
2927                                 nr_ins += bun->instruction_count;
2928                 }
2929 
2930                 /* Calculate thread count. There are certain cutoffs by
2931                  * register count for thread count */
2932 
2933                 unsigned nr_registers = program->work_register_count;
2934 
2935                 unsigned nr_threads =
2936                         (nr_registers <= 4) ? 4 :
2937                         (nr_registers <= 8) ? 2 :
2938                         1;
2939 
2940                 /* Dump stats */
2941 
2942                 fprintf(stderr, "shader%d - %s shader: "
2943                         "%u inst, %u bundles, %u quadwords, "
2944                         "%u registers, %u threads, %u loops, "
2945                         "%u:%u spills:fills\n",
2946                         SHADER_DB_COUNT++,
2947                         ctx->is_blend ? "PAN_SHADER_BLEND" :
2948                         gl_shader_stage_name(ctx->stage),
2949                         nr_ins, nr_bundles, ctx->quadword_count,
2950                         nr_registers, nr_threads,
2951                         ctx->loop_count,
2952                         ctx->spills, ctx->fills);
2953         }
2954 
2955         ralloc_free(ctx);
2956 
2957         return program;
2958 }
2959