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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 <err.h>
26 #include <fcntl.h>
27 #include <stdint.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <sys/mman.h>
31 #include <sys/stat.h>
32 #include <sys/types.h>
33 
34 #include "compiler/glsl/glsl_to_nir.h"
35 #include "compiler/glsl_types.h"
36 #include "compiler/nir/nir_builder.h"
37 #include "util/half_float.h"
38 #include "util/list.h"
39 #include "util/u_debug.h"
40 #include "util/u_dynarray.h"
41 #include "util/u_math.h"
42 
43 #include "compiler.h"
44 #include "helpers.h"
45 #include "midgard.h"
46 #include "midgard_compile.h"
47 #include "midgard_nir.h"
48 #include "midgard_ops.h"
49 #include "midgard_quirks.h"
50 
51 #include "disassemble.h"
52 
53 static const struct debug_named_value midgard_debug_options[] = {
54    {"shaders", MIDGARD_DBG_SHADERS, "Dump shaders in NIR and MIR"},
55    {"shaderdb", MIDGARD_DBG_SHADERDB, "Prints shader-db statistics"},
56    {"inorder", MIDGARD_DBG_INORDER, "Disables out-of-order scheduling"},
57    {"verbose", MIDGARD_DBG_VERBOSE, "Dump shaders verbosely"},
58    {"internal", MIDGARD_DBG_INTERNAL, "Dump internal shaders"},
59    DEBUG_NAMED_VALUE_END};
60 
61 DEBUG_GET_ONCE_FLAGS_OPTION(midgard_debug, "MIDGARD_MESA_DEBUG",
62                             midgard_debug_options, 0)
63 
64 int midgard_debug = 0;
65 
66 static midgard_block *
create_empty_block(compiler_context * ctx)67 create_empty_block(compiler_context *ctx)
68 {
69    midgard_block *blk = rzalloc(ctx, midgard_block);
70 
71    blk->base.predecessors =
72       _mesa_set_create(blk, _mesa_hash_pointer, _mesa_key_pointer_equal);
73 
74    blk->base.name = ctx->block_source_count++;
75 
76    return blk;
77 }
78 
79 static void
schedule_barrier(compiler_context * ctx)80 schedule_barrier(compiler_context *ctx)
81 {
82    midgard_block *temp = ctx->after_block;
83    ctx->after_block = create_empty_block(ctx);
84    ctx->block_count++;
85    list_addtail(&ctx->after_block->base.link, &ctx->blocks);
86    list_inithead(&ctx->after_block->base.instructions);
87    pan_block_add_successor(&ctx->current_block->base, &ctx->after_block->base);
88    ctx->current_block = ctx->after_block;
89    ctx->after_block = temp;
90 }
91 
92 /* Helpers to generate midgard_instruction's using macro magic, since every
93  * driver seems to do it that way */
94 
95 #define EMIT(op, ...) emit_mir_instruction(ctx, v_##op(__VA_ARGS__));
96 
97 #define M_LOAD_STORE(name, store, T)                                           \
98    static midgard_instruction m_##name(unsigned ssa, unsigned address)         \
99    {                                                                           \
100       midgard_instruction i = {                                                \
101          .type = TAG_LOAD_STORE_4,                                             \
102          .mask = 0xF,                                                          \
103          .dest = ~0,                                                           \
104          .src = {~0, ~0, ~0, ~0},                                              \
105          .swizzle = SWIZZLE_IDENTITY_4,                                        \
106          .op = midgard_op_##name,                                              \
107          .load_store =                                                         \
108             {                                                                  \
109                .signed_offset = address,                                       \
110             },                                                                 \
111       };                                                                       \
112                                                                                \
113       if (store) {                                                             \
114          i.src[0] = ssa;                                                       \
115          i.src_types[0] = T;                                                   \
116          i.dest_type = T;                                                      \
117       } else {                                                                 \
118          i.dest = ssa;                                                         \
119          i.dest_type = T;                                                      \
120       }                                                                        \
121       return i;                                                                \
122    }
123 
124 #define M_LOAD(name, T)  M_LOAD_STORE(name, false, T)
125 #define M_STORE(name, T) M_LOAD_STORE(name, true, T)
126 
127 M_LOAD(ld_attr_32, nir_type_uint32);
128 M_LOAD(ld_vary_32, nir_type_uint32);
129 M_LOAD(ld_ubo_u8, nir_type_uint32); /* mandatory extension to 32-bit */
130 M_LOAD(ld_ubo_u16, nir_type_uint32);
131 M_LOAD(ld_ubo_32, nir_type_uint32);
132 M_LOAD(ld_ubo_64, nir_type_uint32);
133 M_LOAD(ld_ubo_128, nir_type_uint32);
134 M_LOAD(ld_u8, nir_type_uint8);
135 M_LOAD(ld_u16, nir_type_uint16);
136 M_LOAD(ld_32, nir_type_uint32);
137 M_LOAD(ld_64, nir_type_uint32);
138 M_LOAD(ld_128, nir_type_uint32);
139 M_STORE(st_u8, nir_type_uint8);
140 M_STORE(st_u16, nir_type_uint16);
141 M_STORE(st_32, nir_type_uint32);
142 M_STORE(st_64, nir_type_uint32);
143 M_STORE(st_128, nir_type_uint32);
144 M_LOAD(ld_tilebuffer_raw, nir_type_uint32);
145 M_LOAD(ld_tilebuffer_16f, nir_type_float16);
146 M_LOAD(ld_tilebuffer_32f, nir_type_float32);
147 M_STORE(st_vary_32, nir_type_uint32);
148 M_LOAD(ld_cubemap_coords, nir_type_uint32);
149 M_LOAD(ldst_mov, nir_type_uint32);
150 M_LOAD(ld_image_32f, nir_type_float32);
151 M_LOAD(ld_image_16f, nir_type_float16);
152 M_LOAD(ld_image_32u, nir_type_uint32);
153 M_LOAD(ld_image_32i, nir_type_int32);
154 M_STORE(st_image_32f, nir_type_float32);
155 M_STORE(st_image_16f, nir_type_float16);
156 M_STORE(st_image_32u, nir_type_uint32);
157 M_STORE(st_image_32i, nir_type_int32);
158 M_LOAD(lea_image, nir_type_uint64);
159 
160 #define M_IMAGE(op)                                                            \
161    static midgard_instruction op##_image(nir_alu_type type, unsigned val,      \
162                                          unsigned address)                     \
163    {                                                                           \
164       switch (type) {                                                          \
165       case nir_type_float32:                                                   \
166          return m_##op##_image_32f(val, address);                              \
167       case nir_type_float16:                                                   \
168          return m_##op##_image_16f(val, address);                              \
169       case nir_type_uint32:                                                    \
170          return m_##op##_image_32u(val, address);                              \
171       case nir_type_int32:                                                     \
172          return m_##op##_image_32i(val, address);                              \
173       default:                                                                 \
174          unreachable("Invalid image type");                                    \
175       }                                                                        \
176    }
177 
178 M_IMAGE(ld);
179 M_IMAGE(st);
180 
181 static midgard_instruction
v_branch(bool conditional,bool invert)182 v_branch(bool conditional, bool invert)
183 {
184    midgard_instruction ins = {
185       .type = TAG_ALU_4,
186       .unit = ALU_ENAB_BRANCH,
187       .compact_branch = true,
188       .branch =
189          {
190             .conditional = conditional,
191             .invert_conditional = invert,
192          },
193       .dest = ~0,
194       .src = {~0, ~0, ~0, ~0},
195    };
196 
197    return ins;
198 }
199 
200 static void
attach_constants(compiler_context * ctx,midgard_instruction * ins,void * constants,int name)201 attach_constants(compiler_context *ctx, midgard_instruction *ins,
202                  void *constants, int name)
203 {
204    ins->has_constants = true;
205    memcpy(&ins->constants, constants, 16);
206 }
207 
208 static int
glsl_type_size(const struct glsl_type * type,bool bindless)209 glsl_type_size(const struct glsl_type *type, bool bindless)
210 {
211    return glsl_count_attribute_slots(type, false);
212 }
213 
214 static bool
midgard_nir_lower_global_load_instr(nir_builder * b,nir_intrinsic_instr * intr,void * data)215 midgard_nir_lower_global_load_instr(nir_builder *b, nir_intrinsic_instr *intr,
216                                     void *data)
217 {
218    if (intr->intrinsic != nir_intrinsic_load_global &&
219        intr->intrinsic != nir_intrinsic_load_shared)
220       return false;
221 
222    unsigned compsz = intr->def.bit_size;
223    unsigned totalsz = compsz * intr->def.num_components;
224    /* 8, 16, 32, 64 and 128 bit loads don't need to be lowered */
225    if (util_bitcount(totalsz) < 2 && totalsz <= 128)
226       return false;
227 
228    b->cursor = nir_before_instr(&intr->instr);
229 
230    nir_def *addr = intr->src[0].ssa;
231 
232    nir_def *comps[MIR_VEC_COMPONENTS];
233    unsigned ncomps = 0;
234 
235    while (totalsz) {
236       unsigned loadsz = MIN2(1 << (util_last_bit(totalsz) - 1), 128);
237       unsigned loadncomps = loadsz / compsz;
238 
239       nir_def *load;
240       if (intr->intrinsic == nir_intrinsic_load_global) {
241          load = nir_load_global(b, addr, compsz / 8, loadncomps, compsz);
242       } else {
243          assert(intr->intrinsic == nir_intrinsic_load_shared);
244          nir_intrinsic_instr *shared_load =
245             nir_intrinsic_instr_create(b->shader, nir_intrinsic_load_shared);
246          shared_load->num_components = loadncomps;
247          shared_load->src[0] = nir_src_for_ssa(addr);
248          nir_intrinsic_set_align(shared_load, compsz / 8, 0);
249          nir_intrinsic_set_base(shared_load, nir_intrinsic_base(intr));
250          nir_def_init(&shared_load->instr, &shared_load->def,
251                       shared_load->num_components, compsz);
252          nir_builder_instr_insert(b, &shared_load->instr);
253          load = &shared_load->def;
254       }
255 
256       for (unsigned i = 0; i < loadncomps; i++)
257          comps[ncomps++] = nir_channel(b, load, i);
258 
259       totalsz -= loadsz;
260       addr = nir_iadd_imm(b, addr, loadsz / 8);
261    }
262 
263    assert(ncomps == intr->def.num_components);
264    nir_def_rewrite_uses(&intr->def, nir_vec(b, comps, ncomps));
265 
266    return true;
267 }
268 
269 static bool
midgard_nir_lower_global_load(nir_shader * shader)270 midgard_nir_lower_global_load(nir_shader *shader)
271 {
272    return nir_shader_intrinsics_pass(
273       shader, midgard_nir_lower_global_load_instr,
274       nir_metadata_control_flow, NULL);
275 }
276 
277 static bool
mdg_should_scalarize(const nir_instr * instr,const void * _unused)278 mdg_should_scalarize(const nir_instr *instr, const void *_unused)
279 {
280    const nir_alu_instr *alu = nir_instr_as_alu(instr);
281 
282    if (nir_src_bit_size(alu->src[0].src) == 64)
283       return true;
284 
285    if (alu->def.bit_size == 64)
286       return true;
287 
288    switch (alu->op) {
289    case nir_op_fdot2:
290    case nir_op_umul_high:
291    case nir_op_imul_high:
292    case nir_op_pack_half_2x16:
293    case nir_op_unpack_half_2x16:
294 
295    /* The LUT unit is scalar */
296    case nir_op_fsqrt:
297    case nir_op_frcp:
298    case nir_op_frsq:
299    case nir_op_fsin_mdg:
300    case nir_op_fcos_mdg:
301    case nir_op_fexp2:
302    case nir_op_flog2:
303       return true;
304    default:
305       return false;
306    }
307 }
308 
309 /* Only vectorize int64 up to vec2 */
310 static uint8_t
midgard_vectorize_filter(const nir_instr * instr,const void * data)311 midgard_vectorize_filter(const nir_instr *instr, const void *data)
312 {
313    if (instr->type != nir_instr_type_alu)
314       return 0;
315 
316    const nir_alu_instr *alu = nir_instr_as_alu(instr);
317    int src_bit_size = nir_src_bit_size(alu->src[0].src);
318    int dst_bit_size = alu->def.bit_size;
319 
320    if (src_bit_size == 64 || dst_bit_size == 64)
321       return 2;
322 
323    return 4;
324 }
325 
326 static nir_mem_access_size_align
mem_access_size_align_cb(nir_intrinsic_op intrin,uint8_t bytes,uint8_t bit_size,uint32_t align_mul,uint32_t align_offset,bool offset_is_const,enum gl_access_qualifier access,const void * cb_data)327 mem_access_size_align_cb(nir_intrinsic_op intrin, uint8_t bytes,
328                          uint8_t bit_size, uint32_t align_mul,
329                          uint32_t align_offset, bool offset_is_const,
330                          enum gl_access_qualifier access, const void *cb_data)
331 {
332    uint32_t align = nir_combined_align(align_mul, align_offset);
333    assert(util_is_power_of_two_nonzero(align));
334 
335    /* No more than 16 bytes at a time. */
336    bytes = MIN2(bytes, 16);
337 
338    /* If the number of bytes is a multiple of 4, use 32-bit loads. Else if it's
339     * a multiple of 2, use 16-bit loads. Else use 8-bit loads.
340     *
341     * But if we're only aligned to 1 byte, use 8-bit loads. If we're only
342     * aligned to 2 bytes, use 16-bit loads, unless we needed 8-bit loads due to
343     * the size.
344     */
345    if ((bytes & 1) || (align == 1))
346       bit_size = 8;
347    else if ((bytes & 2) || (align == 2))
348       bit_size = 16;
349    else if (bit_size >= 32)
350       bit_size = 32;
351 
352    unsigned num_comps = MIN2(bytes / (bit_size / 8), 4);
353 
354    return (nir_mem_access_size_align){
355       .num_components = num_comps,
356       .bit_size = bit_size,
357       .align = bit_size / 8,
358       .shift = nir_mem_access_shift_method_scalar,
359    };
360 }
361 
362 static uint8_t
lower_vec816_alu(const nir_instr * instr,const void * cb_data)363 lower_vec816_alu(const nir_instr *instr, const void *cb_data)
364 {
365   return 4;
366 }
367 
368 void
midgard_preprocess_nir(nir_shader * nir,unsigned gpu_id)369 midgard_preprocess_nir(nir_shader *nir, unsigned gpu_id)
370 {
371    unsigned quirks = midgard_get_quirks(gpu_id);
372 
373    /* Lower gl_Position pre-optimisation, but after lowering vars to ssa
374     * (so we don't accidentally duplicate the epilogue since mesa/st has
375     * messed with our I/O quite a bit already).
376     */
377    NIR_PASS(_, nir, nir_lower_vars_to_ssa);
378 
379    if (nir->info.stage == MESA_SHADER_VERTEX) {
380       NIR_PASS(_, nir, pan_nir_lower_vertex_id);
381       NIR_PASS(_, nir, nir_lower_viewport_transform);
382       NIR_PASS(_, nir, nir_lower_point_size, 1.0, 0.0);
383    }
384 
385    NIR_PASS(_, nir, nir_lower_var_copies);
386    NIR_PASS(_, nir, nir_lower_vars_to_ssa);
387    NIR_PASS(_, nir, nir_split_var_copies);
388    NIR_PASS(_, nir, nir_lower_var_copies);
389    NIR_PASS(_, nir, nir_lower_global_vars_to_local);
390    NIR_PASS(_, nir, nir_lower_var_copies);
391    NIR_PASS(_, nir, nir_lower_vars_to_ssa);
392 
393    NIR_PASS(_, nir, nir_lower_io, nir_var_shader_in | nir_var_shader_out,
394             glsl_type_size, nir_lower_io_use_interpolated_input_intrinsics);
395 
396    if (nir->info.stage == MESA_SHADER_VERTEX) {
397       /* nir_lower[_explicit]_io is lazy and emits mul+add chains even
398        * for offsets it could figure out are constant.  Do some
399        * constant folding before pan_nir_lower_store_component below.
400        */
401       NIR_PASS(_, nir, nir_opt_constant_folding);
402       NIR_PASS(_, nir, pan_nir_lower_store_component);
403    }
404 
405    /* Could be eventually useful for Vulkan, but we don't expect it to have
406     * the support, so limit it to compute */
407    if (gl_shader_stage_is_compute(nir->info.stage)) {
408       nir_lower_mem_access_bit_sizes_options mem_size_options = {
409          .modes = nir_var_mem_ubo | nir_var_mem_ssbo |
410                   nir_var_mem_constant | nir_var_mem_task_payload |
411                   nir_var_shader_temp | nir_var_function_temp |
412                   nir_var_mem_global | nir_var_mem_shared,
413          .callback = mem_access_size_align_cb,
414       };
415 
416       NIR_PASS(_, nir, nir_lower_mem_access_bit_sizes, &mem_size_options);
417       NIR_PASS(_, nir, nir_lower_alu_width, lower_vec816_alu, NULL);
418       NIR_PASS(_, nir, nir_lower_alu_vec8_16_srcs);
419    }
420 
421    NIR_PASS(_, nir, nir_lower_ssbo, NULL);
422    NIR_PASS(_, nir, pan_nir_lower_zs_store);
423 
424    NIR_PASS(_, nir, nir_lower_frexp);
425    NIR_PASS(_, nir, midgard_nir_lower_global_load);
426 
427    nir_lower_idiv_options idiv_options = {
428       .allow_fp16 = true,
429    };
430 
431    NIR_PASS(_, nir, nir_lower_idiv, &idiv_options);
432 
433    nir_lower_tex_options lower_tex_options = {
434       .lower_txs_lod = true,
435       .lower_txp = ~0,
436       .lower_tg4_broadcom_swizzle = true,
437       .lower_txd = true,
438       .lower_invalid_implicit_lod = true,
439    };
440 
441    NIR_PASS(_, nir, nir_lower_tex, &lower_tex_options);
442    NIR_PASS(_, nir, nir_lower_image_atomics_to_global);
443 
444    /* TEX_GRAD fails to apply sampler descriptor settings on some
445     * implementations, requiring a lowering.
446     */
447    if (quirks & MIDGARD_BROKEN_LOD)
448       NIR_PASS(_, nir, midgard_nir_lod_errata);
449 
450    /* lower MSAA image operations to 3D load before coordinate lowering */
451    NIR_PASS(_, nir, pan_nir_lower_image_ms);
452 
453    /* Midgard image ops coordinates are 16-bit instead of 32-bit */
454    NIR_PASS(_, nir, midgard_nir_lower_image_bitsize);
455 
456    if (nir->info.stage == MESA_SHADER_FRAGMENT)
457       NIR_PASS(_, nir, nir_lower_helper_writes, true);
458 
459    NIR_PASS(_, nir, pan_lower_helper_invocation);
460    NIR_PASS(_, nir, pan_lower_sample_pos);
461    NIR_PASS(_, nir, midgard_nir_lower_algebraic_early);
462    NIR_PASS(_, nir, nir_lower_alu_to_scalar, mdg_should_scalarize, NULL);
463    NIR_PASS(_, nir, nir_lower_flrp, 16 | 32 | 64, false /* always_precise */);
464    NIR_PASS(_, nir, nir_lower_var_copies);
465 }
466 
467 static void
optimise_nir(nir_shader * nir,unsigned quirks,bool is_blend)468 optimise_nir(nir_shader *nir, unsigned quirks, bool is_blend)
469 {
470    bool progress;
471 
472    do {
473       progress = false;
474 
475       NIR_PASS(progress, nir, nir_lower_vars_to_ssa);
476 
477       NIR_PASS(progress, nir, nir_copy_prop);
478       NIR_PASS(progress, nir, nir_opt_remove_phis);
479       NIR_PASS(progress, nir, nir_opt_dce);
480       NIR_PASS(progress, nir, nir_opt_dead_cf);
481       NIR_PASS(progress, nir, nir_opt_cse);
482       NIR_PASS(progress, nir, nir_opt_peephole_select, 64, false, true);
483       NIR_PASS(progress, nir, nir_opt_algebraic);
484       NIR_PASS(progress, nir, nir_opt_constant_folding);
485       NIR_PASS(progress, nir, nir_opt_undef);
486       NIR_PASS(progress, nir, nir_lower_undef_to_zero);
487 
488       NIR_PASS(progress, nir, nir_opt_loop_unroll);
489 
490       NIR_PASS(progress, nir, nir_opt_vectorize, midgard_vectorize_filter,
491                NULL);
492    } while (progress);
493 
494    NIR_PASS(_, nir, nir_lower_alu_to_scalar, mdg_should_scalarize, NULL);
495 
496    /* Run after opts so it can hit more */
497    if (!is_blend)
498       NIR_PASS(progress, nir, nir_fuse_io_16);
499 
500    do {
501       progress = false;
502 
503       NIR_PASS(progress, nir, nir_opt_dce);
504       NIR_PASS(progress, nir, nir_opt_algebraic);
505       NIR_PASS(progress, nir, nir_opt_constant_folding);
506       NIR_PASS(progress, nir, nir_copy_prop);
507    } while (progress);
508 
509    NIR_PASS(progress, nir, nir_opt_algebraic_late);
510    NIR_PASS(progress, nir, nir_opt_algebraic_distribute_src_mods);
511 
512    /* We implement booleans as 32-bit 0/~0 */
513    NIR_PASS(progress, nir, nir_lower_bool_to_int32);
514 
515    /* Now that booleans are lowered, we can run out late opts */
516    NIR_PASS(progress, nir, midgard_nir_lower_algebraic_late);
517    NIR_PASS(progress, nir, midgard_nir_cancel_inot);
518    NIR_PASS(_, nir, midgard_nir_type_csel);
519 
520    /* Clean up after late opts */
521    do {
522       progress = false;
523 
524       NIR_PASS(progress, nir, nir_opt_dce);
525       NIR_PASS(progress, nir, nir_opt_constant_folding);
526       NIR_PASS(progress, nir, nir_copy_prop);
527    } while (progress);
528 
529    /* Backend scheduler is purely local, so do some global optimizations
530     * to reduce register pressure. */
531    nir_move_options move_all = nir_move_const_undef | nir_move_load_ubo |
532                                nir_move_load_input | nir_move_comparisons |
533                                nir_move_copies | nir_move_load_ssbo;
534 
535    NIR_PASS(_, nir, nir_opt_sink, move_all);
536    NIR_PASS(_, nir, nir_opt_move, move_all);
537 
538    /* Take us out of SSA */
539    NIR_PASS(progress, nir, nir_convert_from_ssa, true);
540 
541    /* We are a vector architecture; write combine where possible */
542    NIR_PASS(progress, nir, nir_move_vec_src_uses_to_dest, false);
543    NIR_PASS(progress, nir, nir_lower_vec_to_regs, NULL, NULL);
544 
545    NIR_PASS(progress, nir, nir_opt_dce);
546    nir_trivialize_registers(nir);
547 }
548 
549 /* Do not actually emit a load; instead, cache the constant for inlining */
550 
551 static void
emit_load_const(compiler_context * ctx,nir_load_const_instr * instr)552 emit_load_const(compiler_context *ctx, nir_load_const_instr *instr)
553 {
554    nir_def def = instr->def;
555 
556    midgard_constants *consts = rzalloc(ctx, midgard_constants);
557 
558    assert(instr->def.num_components * instr->def.bit_size <=
559           sizeof(*consts) * 8);
560 
561 #define RAW_CONST_COPY(bits)                                                   \
562    nir_const_value_to_array(consts->u##bits, instr->value,                     \
563                             instr->def.num_components, u##bits)
564 
565    switch (instr->def.bit_size) {
566    case 64:
567       RAW_CONST_COPY(64);
568       break;
569    case 32:
570       RAW_CONST_COPY(32);
571       break;
572    case 16:
573       RAW_CONST_COPY(16);
574       break;
575    case 8:
576       RAW_CONST_COPY(8);
577       break;
578    default:
579       unreachable("Invalid bit_size for load_const instruction\n");
580    }
581 
582    /* Shifted for SSA, +1 for off-by-one */
583    _mesa_hash_table_u64_insert(ctx->ssa_constants, (def.index << 1) + 1,
584                                consts);
585 }
586 
587 /* Normally constants are embedded implicitly, but for I/O and such we have to
588  * explicitly emit a move with the constant source */
589 
590 static void
emit_explicit_constant(compiler_context * ctx,unsigned node)591 emit_explicit_constant(compiler_context *ctx, unsigned node)
592 {
593    void *constant_value =
594       _mesa_hash_table_u64_search(ctx->ssa_constants, node + 1);
595 
596    if (constant_value) {
597       midgard_instruction ins =
598          v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT), node);
599       attach_constants(ctx, &ins, constant_value, node + 1);
600       emit_mir_instruction(ctx, ins);
601    }
602 }
603 
604 static bool
nir_is_non_scalar_swizzle(nir_alu_src * src,unsigned nr_components)605 nir_is_non_scalar_swizzle(nir_alu_src *src, unsigned nr_components)
606 {
607    unsigned comp = src->swizzle[0];
608 
609    for (unsigned c = 1; c < nr_components; ++c) {
610       if (src->swizzle[c] != comp)
611          return true;
612    }
613 
614    return false;
615 }
616 
617 #define ALU_CASE(nir, _op)                                                     \
618    case nir_op_##nir:                                                          \
619       op = midgard_alu_op_##_op;                                               \
620       assert(src_bitsize == dst_bitsize);                                      \
621       break;
622 
623 #define ALU_CASE_RTZ(nir, _op)                                                 \
624    case nir_op_##nir:                                                          \
625       op = midgard_alu_op_##_op;                                               \
626       roundmode = MIDGARD_RTZ;                                                 \
627       break;
628 
629 #define ALU_CHECK_CMP()                                                        \
630    assert(src_bitsize == 16 || src_bitsize == 32 || src_bitsize == 64);        \
631    assert(dst_bitsize == 16 || dst_bitsize == 32);
632 
633 #define ALU_CASE_BCAST(nir, _op, count)                                        \
634    case nir_op_##nir:                                                          \
635       op = midgard_alu_op_##_op;                                               \
636       broadcast_swizzle = count;                                               \
637       ALU_CHECK_CMP();                                                         \
638       break;
639 
640 #define ALU_CASE_CMP(nir, _op)                                                 \
641    case nir_op_##nir:                                                          \
642       op = midgard_alu_op_##_op;                                               \
643       ALU_CHECK_CMP();                                                         \
644       break;
645 
646 static void
mir_copy_src(midgard_instruction * ins,nir_alu_instr * instr,unsigned i,unsigned to,bool is_int,unsigned bcast_count)647 mir_copy_src(midgard_instruction *ins, nir_alu_instr *instr, unsigned i,
648              unsigned to, bool is_int, unsigned bcast_count)
649 {
650    nir_alu_src src = instr->src[i];
651    unsigned bits = nir_src_bit_size(src.src);
652 
653    ins->src[to] = nir_src_index(NULL, &src.src);
654    ins->src_types[to] = nir_op_infos[instr->op].input_types[i] | bits;
655 
656    /* Figure out which component we should fill unused channels with. This
657     * doesn't matter too much in the non-broadcast case, but it makes
658     * should that scalar sources are packed with replicated swizzles,
659     * which works around issues seen with the combination of source
660     * expansion and destination shrinking.
661     */
662    unsigned replicate_c = 0;
663    if (bcast_count) {
664       replicate_c = bcast_count - 1;
665    } else {
666       for (unsigned c = 0; c < NIR_MAX_VEC_COMPONENTS; ++c) {
667          if (nir_alu_instr_channel_used(instr, i, c))
668             replicate_c = c;
669       }
670    }
671 
672    for (unsigned c = 0; c < NIR_MAX_VEC_COMPONENTS; ++c) {
673       ins->swizzle[to][c] =
674          src.swizzle[((!bcast_count || c < bcast_count) &&
675                       nir_alu_instr_channel_used(instr, i, c))
676                         ? c
677                         : replicate_c];
678    }
679 }
680 
681 static void
emit_alu(compiler_context * ctx,nir_alu_instr * instr)682 emit_alu(compiler_context *ctx, nir_alu_instr *instr)
683 {
684    unsigned nr_components = instr->def.num_components;
685    unsigned nr_inputs = nir_op_infos[instr->op].num_inputs;
686    unsigned op = 0;
687 
688    /* Number of components valid to check for the instruction (the rest
689     * will be forced to the last), or 0 to use as-is. Relevant as
690     * ball-type instructions have a channel count in NIR but are all vec4
691     * in Midgard */
692 
693    unsigned broadcast_swizzle = 0;
694 
695    /* Should we swap arguments? */
696    bool flip_src12 = false;
697 
698    ASSERTED unsigned src_bitsize = nir_src_bit_size(instr->src[0].src);
699    unsigned dst_bitsize = instr->def.bit_size;
700 
701    enum midgard_roundmode roundmode = MIDGARD_RTE;
702 
703    switch (instr->op) {
704       ALU_CASE(fadd, fadd);
705       ALU_CASE(fmul, fmul);
706       ALU_CASE(fmin, fmin);
707       ALU_CASE(fmax, fmax);
708       ALU_CASE(imin, imin);
709       ALU_CASE(imax, imax);
710       ALU_CASE(umin, umin);
711       ALU_CASE(umax, umax);
712       ALU_CASE(ffloor, ffloor);
713       ALU_CASE(fround_even, froundeven);
714       ALU_CASE(ftrunc, ftrunc);
715       ALU_CASE(fceil, fceil);
716       ALU_CASE(fdot3, fdot3);
717       ALU_CASE(fdot4, fdot4);
718       ALU_CASE(iadd, iadd);
719       ALU_CASE(isub, isub);
720       ALU_CASE(iadd_sat, iaddsat);
721       ALU_CASE(isub_sat, isubsat);
722       ALU_CASE(uadd_sat, uaddsat);
723       ALU_CASE(usub_sat, usubsat);
724       ALU_CASE(imul, imul);
725       ALU_CASE(imul_high, imul);
726       ALU_CASE(umul_high, imul);
727       ALU_CASE(uclz, iclz);
728 
729       /* Zero shoved as second-arg */
730       ALU_CASE(iabs, iabsdiff);
731 
732       ALU_CASE(uabs_isub, iabsdiff);
733       ALU_CASE(uabs_usub, uabsdiff);
734 
735       ALU_CASE(mov, imov);
736 
737       ALU_CASE_CMP(feq32, feq);
738       ALU_CASE_CMP(fneu32, fne);
739       ALU_CASE_CMP(flt32, flt);
740       ALU_CASE_CMP(ieq32, ieq);
741       ALU_CASE_CMP(ine32, ine);
742       ALU_CASE_CMP(ilt32, ilt);
743       ALU_CASE_CMP(ult32, ult);
744 
745       /* We don't have a native b2f32 instruction. Instead, like many
746        * GPUs, we exploit booleans as 0/~0 for false/true, and
747        * correspondingly AND
748        * by 1.0 to do the type conversion. For the moment, prime us
749        * to emit:
750        *
751        * iand [whatever], #0
752        *
753        * At the end of emit_alu (as MIR), we'll fix-up the constant
754        */
755 
756       ALU_CASE_CMP(b2f32, iand);
757       ALU_CASE_CMP(b2f16, iand);
758       ALU_CASE_CMP(b2i32, iand);
759       ALU_CASE_CMP(b2i16, iand);
760 
761       ALU_CASE(frcp, frcp);
762       ALU_CASE(frsq, frsqrt);
763       ALU_CASE(fsqrt, fsqrt);
764       ALU_CASE(fexp2, fexp2);
765       ALU_CASE(flog2, flog2);
766 
767       ALU_CASE_RTZ(f2i64, f2i_rte);
768       ALU_CASE_RTZ(f2u64, f2u_rte);
769       ALU_CASE_RTZ(i2f64, i2f_rte);
770       ALU_CASE_RTZ(u2f64, u2f_rte);
771 
772       ALU_CASE_RTZ(f2i32, f2i_rte);
773       ALU_CASE_RTZ(f2u32, f2u_rte);
774       ALU_CASE_RTZ(i2f32, i2f_rte);
775       ALU_CASE_RTZ(u2f32, u2f_rte);
776 
777       ALU_CASE_RTZ(f2i8, f2i_rte);
778       ALU_CASE_RTZ(f2u8, f2u_rte);
779 
780       ALU_CASE_RTZ(f2i16, f2i_rte);
781       ALU_CASE_RTZ(f2u16, f2u_rte);
782       ALU_CASE_RTZ(i2f16, i2f_rte);
783       ALU_CASE_RTZ(u2f16, u2f_rte);
784 
785       ALU_CASE(fsin_mdg, fsinpi);
786       ALU_CASE(fcos_mdg, fcospi);
787 
788       /* We'll get 0 in the second arg, so:
789        * ~a = ~(a | 0) = nor(a, 0) */
790       ALU_CASE(inot, inor);
791       ALU_CASE(iand, iand);
792       ALU_CASE(ior, ior);
793       ALU_CASE(ixor, ixor);
794       ALU_CASE(ishl, ishl);
795       ALU_CASE(ishr, iasr);
796       ALU_CASE(ushr, ilsr);
797 
798       ALU_CASE_BCAST(b32all_fequal2, fball_eq, 2);
799       ALU_CASE_BCAST(b32all_fequal3, fball_eq, 3);
800       ALU_CASE_CMP(b32all_fequal4, fball_eq);
801 
802       ALU_CASE_BCAST(b32any_fnequal2, fbany_neq, 2);
803       ALU_CASE_BCAST(b32any_fnequal3, fbany_neq, 3);
804       ALU_CASE_CMP(b32any_fnequal4, fbany_neq);
805 
806       ALU_CASE_BCAST(b32all_iequal2, iball_eq, 2);
807       ALU_CASE_BCAST(b32all_iequal3, iball_eq, 3);
808       ALU_CASE_CMP(b32all_iequal4, iball_eq);
809 
810       ALU_CASE_BCAST(b32any_inequal2, ibany_neq, 2);
811       ALU_CASE_BCAST(b32any_inequal3, ibany_neq, 3);
812       ALU_CASE_CMP(b32any_inequal4, ibany_neq);
813 
814       /* Source mods will be shoved in later */
815       ALU_CASE(fabs, fmov);
816       ALU_CASE(fneg, fmov);
817       ALU_CASE(fsat, fmov);
818       ALU_CASE(fsat_signed, fmov);
819       ALU_CASE(fclamp_pos, fmov);
820 
821       /* For size conversion, we use a move. Ideally though we would squash
822        * these ops together; maybe that has to happen after in NIR as part of
823        * propagation...? An earlier algebraic pass ensured we step down by
824        * only / exactly one size. If stepping down, we use a dest override to
825        * reduce the size; if stepping up, we use a larger-sized move with a
826        * half source and a sign/zero-extension modifier */
827 
828    case nir_op_i2i8:
829    case nir_op_i2i16:
830    case nir_op_i2i32:
831    case nir_op_i2i64:
832    case nir_op_u2u8:
833    case nir_op_u2u16:
834    case nir_op_u2u32:
835    case nir_op_u2u64:
836    case nir_op_f2f16:
837    case nir_op_f2f32:
838    case nir_op_f2f64: {
839       if (instr->op == nir_op_f2f16 || instr->op == nir_op_f2f32 ||
840           instr->op == nir_op_f2f64)
841          op = midgard_alu_op_fmov;
842       else
843          op = midgard_alu_op_imov;
844 
845       break;
846    }
847 
848       /* For greater-or-equal, we lower to less-or-equal and flip the
849        * arguments */
850 
851    case nir_op_fge:
852    case nir_op_fge32:
853    case nir_op_ige32:
854    case nir_op_uge32: {
855       op = instr->op == nir_op_fge     ? midgard_alu_op_fle
856            : instr->op == nir_op_fge32 ? midgard_alu_op_fle
857            : instr->op == nir_op_ige32 ? midgard_alu_op_ile
858            : instr->op == nir_op_uge32 ? midgard_alu_op_ule
859                                        : 0;
860 
861       flip_src12 = true;
862       ALU_CHECK_CMP();
863       break;
864    }
865 
866    case nir_op_b32csel:
867    case nir_op_b32fcsel_mdg: {
868       bool mixed = nir_is_non_scalar_swizzle(&instr->src[0], nr_components);
869       bool is_float = instr->op == nir_op_b32fcsel_mdg;
870       op = is_float ? (mixed ? midgard_alu_op_fcsel_v : midgard_alu_op_fcsel)
871                     : (mixed ? midgard_alu_op_icsel_v : midgard_alu_op_icsel);
872 
873       int index = nir_src_index(ctx, &instr->src[0].src);
874       emit_explicit_constant(ctx, index);
875 
876       break;
877    }
878 
879    case nir_op_unpack_32_2x16:
880    case nir_op_unpack_32_4x8:
881    case nir_op_pack_32_2x16:
882    case nir_op_pack_32_4x8: {
883       op = midgard_alu_op_imov;
884       break;
885    }
886 
887    case nir_op_unpack_64_2x32:
888    case nir_op_unpack_64_4x16:
889    case nir_op_pack_64_2x32:
890    case nir_op_pack_64_4x16: {
891       op = midgard_alu_op_imov;
892       break;
893    }
894 
895    default:
896       mesa_loge("Unhandled ALU op %s\n", nir_op_infos[instr->op].name);
897       assert(0);
898       return;
899    }
900 
901    /* Promote imov to fmov if it might help inline a constant */
902    if (op == midgard_alu_op_imov && nir_src_is_const(instr->src[0].src) &&
903        nir_src_bit_size(instr->src[0].src) == 32 &&
904        nir_is_same_comp_swizzle(instr->src[0].swizzle,
905                                 nir_src_num_components(instr->src[0].src))) {
906       op = midgard_alu_op_fmov;
907    }
908 
909    /* Midgard can perform certain modifiers on output of an ALU op */
910 
911    unsigned outmod = 0;
912    bool is_int = midgard_is_integer_op(op);
913 
914    if (instr->op == nir_op_umul_high || instr->op == nir_op_imul_high) {
915       outmod = midgard_outmod_keephi;
916    } else if (midgard_is_integer_out_op(op)) {
917       outmod = midgard_outmod_keeplo;
918    } else if (instr->op == nir_op_fsat) {
919       outmod = midgard_outmod_clamp_0_1;
920    } else if (instr->op == nir_op_fsat_signed) {
921       outmod = midgard_outmod_clamp_m1_1;
922    } else if (instr->op == nir_op_fclamp_pos) {
923       outmod = midgard_outmod_clamp_0_inf;
924    }
925 
926    /* Fetch unit, quirks, etc information */
927    unsigned opcode_props = alu_opcode_props[op].props;
928    bool quirk_flipped_r24 = opcode_props & QUIRK_FLIPPED_R24;
929 
930    midgard_instruction ins = {
931       .type = TAG_ALU_4,
932       .dest_type = nir_op_infos[instr->op].output_type | dst_bitsize,
933       .roundmode = roundmode,
934    };
935 
936    ins.dest = nir_def_index_with_mask(&instr->def, &ins.mask);
937 
938    for (unsigned i = nr_inputs; i < ARRAY_SIZE(ins.src); ++i)
939       ins.src[i] = ~0;
940 
941    if (quirk_flipped_r24) {
942       ins.src[0] = ~0;
943       mir_copy_src(&ins, instr, 0, 1, is_int, broadcast_swizzle);
944    } else {
945       for (unsigned i = 0; i < nr_inputs; ++i) {
946          unsigned to = i;
947 
948          if (instr->op == nir_op_b32csel || instr->op == nir_op_b32fcsel_mdg) {
949             /* The condition is the first argument; move
950              * the other arguments up one to be a binary
951              * instruction for Midgard with the condition
952              * last */
953 
954             if (i == 0)
955                to = 2;
956             else if (flip_src12)
957                to = 2 - i;
958             else
959                to = i - 1;
960          } else if (flip_src12) {
961             to = 1 - to;
962          }
963 
964          mir_copy_src(&ins, instr, i, to, is_int, broadcast_swizzle);
965       }
966    }
967 
968    if (instr->op == nir_op_fneg || instr->op == nir_op_fabs) {
969       /* Lowered to move */
970       if (instr->op == nir_op_fneg)
971          ins.src_neg[1] ^= true;
972 
973       if (instr->op == nir_op_fabs)
974          ins.src_abs[1] = true;
975    }
976 
977    ins.op = op;
978    ins.outmod = outmod;
979 
980    /* Late fixup for emulated instructions */
981 
982    if (instr->op == nir_op_b2f32 || instr->op == nir_op_b2i32) {
983       /* Presently, our second argument is an inline #0 constant.
984        * Switch over to an embedded 1.0 constant (that can't fit
985        * inline, since we're 32-bit, not 16-bit like the inline
986        * constants) */
987 
988       ins.has_inline_constant = false;
989       ins.src[1] = SSA_FIXED_REGISTER(REGISTER_CONSTANT);
990       ins.src_types[1] = nir_type_float32;
991       ins.has_constants = true;
992 
993       if (instr->op == nir_op_b2f32)
994          ins.constants.f32[0] = 1.0f;
995       else
996          ins.constants.i32[0] = 1;
997 
998       for (unsigned c = 0; c < 16; ++c)
999          ins.swizzle[1][c] = 0;
1000    } else if (instr->op == nir_op_b2f16) {
1001       ins.src[1] = SSA_FIXED_REGISTER(REGISTER_CONSTANT);
1002       ins.src_types[1] = nir_type_float16;
1003       ins.has_constants = true;
1004       ins.constants.i16[0] = _mesa_float_to_half(1.0);
1005 
1006       for (unsigned c = 0; c < 16; ++c)
1007          ins.swizzle[1][c] = 0;
1008    } else if (nr_inputs == 1 && !quirk_flipped_r24) {
1009       /* Lots of instructions need a 0 plonked in */
1010       ins.has_inline_constant = false;
1011       ins.src[1] = SSA_FIXED_REGISTER(REGISTER_CONSTANT);
1012       ins.src_types[1] = ins.src_types[0];
1013       ins.has_constants = true;
1014       ins.constants.u32[0] = 0;
1015 
1016       for (unsigned c = 0; c < 16; ++c)
1017          ins.swizzle[1][c] = 0;
1018    } else if (instr->op == nir_op_pack_32_2x16) {
1019       ins.dest_type = nir_type_uint16;
1020       ins.mask = mask_of(nr_components * 2);
1021       ins.is_pack = true;
1022    } else if (instr->op == nir_op_pack_32_4x8) {
1023       ins.dest_type = nir_type_uint8;
1024       ins.mask = mask_of(nr_components * 4);
1025       ins.is_pack = true;
1026    } else if (instr->op == nir_op_unpack_32_2x16) {
1027       ins.dest_type = nir_type_uint32;
1028       ins.mask = mask_of(nr_components >> 1);
1029       ins.is_pack = true;
1030    } else if (instr->op == nir_op_unpack_32_4x8) {
1031       ins.dest_type = nir_type_uint32;
1032       ins.mask = mask_of(nr_components >> 2);
1033       ins.is_pack = true;
1034    }
1035 
1036    emit_mir_instruction(ctx, ins);
1037 }
1038 
1039 #undef ALU_CASE
1040 
1041 static void
mir_set_intr_mask(nir_instr * instr,midgard_instruction * ins,bool is_read)1042 mir_set_intr_mask(nir_instr *instr, midgard_instruction *ins, bool is_read)
1043 {
1044    nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
1045    unsigned nir_mask = 0;
1046    unsigned dsize = 0;
1047 
1048    if (is_read) {
1049       nir_mask = mask_of(nir_intrinsic_dest_components(intr));
1050 
1051       /* Extension is mandatory for 8/16-bit loads */
1052       dsize = intr->def.bit_size == 64 ? 64 : 32;
1053    } else {
1054       nir_mask = nir_intrinsic_write_mask(intr);
1055       dsize = OP_IS_COMMON_STORE(ins->op) ? nir_src_bit_size(intr->src[0]) : 32;
1056    }
1057 
1058    /* Once we have the NIR mask, we need to normalize to work in 32-bit space */
1059    unsigned bytemask = pan_to_bytemask(dsize, nir_mask);
1060    ins->dest_type = nir_type_uint | dsize;
1061    mir_set_bytemask(ins, bytemask);
1062 }
1063 
1064 /* Uniforms and UBOs use a shared code path, as uniforms are just (slightly
1065  * optimized) versions of UBO #0 */
1066 
1067 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,unsigned nr_comps)1068 emit_ubo_read(compiler_context *ctx, nir_instr *instr, unsigned dest,
1069               unsigned offset, nir_src *indirect_offset,
1070               unsigned indirect_shift, unsigned index, unsigned nr_comps)
1071 {
1072    midgard_instruction ins;
1073 
1074    unsigned dest_size = (instr->type == nir_instr_type_intrinsic)
1075                            ? nir_instr_as_intrinsic(instr)->def.bit_size
1076                            : 32;
1077 
1078    unsigned bitsize = dest_size * nr_comps;
1079 
1080    /* Pick the smallest intrinsic to avoid out-of-bounds reads */
1081    if (bitsize <= 8)
1082       ins = m_ld_ubo_u8(dest, 0);
1083    else if (bitsize <= 16)
1084       ins = m_ld_ubo_u16(dest, 0);
1085    else if (bitsize <= 32)
1086       ins = m_ld_ubo_32(dest, 0);
1087    else if (bitsize <= 64)
1088       ins = m_ld_ubo_64(dest, 0);
1089    else if (bitsize <= 128)
1090       ins = m_ld_ubo_128(dest, 0);
1091    else
1092       unreachable("Invalid UBO read size");
1093 
1094    ins.constants.u32[0] = offset;
1095 
1096    if (instr->type == nir_instr_type_intrinsic)
1097       mir_set_intr_mask(instr, &ins, true);
1098 
1099    if (indirect_offset) {
1100       ins.src[2] = nir_src_index(ctx, indirect_offset);
1101       ins.src_types[2] = nir_type_uint32;
1102       ins.load_store.index_shift = indirect_shift;
1103 
1104       /* X component for the whole swizzle to prevent register
1105        * pressure from ballooning from the extra components */
1106       for (unsigned i = 0; i < ARRAY_SIZE(ins.swizzle[2]); ++i)
1107          ins.swizzle[2][i] = 0;
1108    } else {
1109       ins.load_store.index_reg = REGISTER_LDST_ZERO;
1110    }
1111 
1112    if (indirect_offset && !indirect_shift)
1113       mir_set_ubo_offset(&ins, indirect_offset, offset);
1114 
1115    midgard_pack_ubo_index_imm(&ins.load_store, index);
1116 
1117    return emit_mir_instruction(ctx, ins);
1118 }
1119 
1120 /* Globals are like UBOs if you squint. And shared memory is like globals if
1121  * you squint even harder */
1122 
1123 static void
emit_global(compiler_context * ctx,nir_instr * instr,bool is_read,unsigned srcdest,nir_src * offset,unsigned seg)1124 emit_global(compiler_context *ctx, nir_instr *instr, bool is_read,
1125             unsigned srcdest, nir_src *offset, unsigned seg)
1126 {
1127    midgard_instruction ins;
1128 
1129    nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
1130    if (is_read) {
1131       unsigned bitsize = intr->def.bit_size * intr->def.num_components;
1132 
1133       switch (bitsize) {
1134       case 8:
1135          ins = m_ld_u8(srcdest, 0);
1136          break;
1137       case 16:
1138          ins = m_ld_u16(srcdest, 0);
1139          break;
1140       case 32:
1141          ins = m_ld_32(srcdest, 0);
1142          break;
1143       case 64:
1144          ins = m_ld_64(srcdest, 0);
1145          break;
1146       case 128:
1147          ins = m_ld_128(srcdest, 0);
1148          break;
1149       default:
1150          unreachable("Invalid global read size");
1151       }
1152 
1153       mir_set_intr_mask(instr, &ins, is_read);
1154 
1155       /* For anything not aligned on 32bit, make sure we write full
1156        * 32 bits registers. */
1157       if (bitsize & 31) {
1158          unsigned comps_per_32b = 32 / intr->def.bit_size;
1159 
1160          for (unsigned c = 0; c < 4 * comps_per_32b; c += comps_per_32b) {
1161             if (!(ins.mask & BITFIELD_RANGE(c, comps_per_32b)))
1162                continue;
1163 
1164             unsigned base = ~0;
1165             for (unsigned i = 0; i < comps_per_32b; i++) {
1166                if (ins.mask & BITFIELD_BIT(c + i)) {
1167                   base = ins.swizzle[0][c + i];
1168                   break;
1169                }
1170             }
1171 
1172             assert(base != ~0);
1173 
1174             for (unsigned i = 0; i < comps_per_32b; i++) {
1175                if (!(ins.mask & BITFIELD_BIT(c + i))) {
1176                   ins.swizzle[0][c + i] = base + i;
1177                   ins.mask |= BITFIELD_BIT(c + i);
1178                }
1179                assert(ins.swizzle[0][c + i] == base + i);
1180             }
1181          }
1182       }
1183    } else {
1184       unsigned bitsize =
1185          nir_src_bit_size(intr->src[0]) * nir_src_num_components(intr->src[0]);
1186 
1187       if (bitsize == 8)
1188          ins = m_st_u8(srcdest, 0);
1189       else if (bitsize == 16)
1190          ins = m_st_u16(srcdest, 0);
1191       else if (bitsize <= 32)
1192          ins = m_st_32(srcdest, 0);
1193       else if (bitsize <= 64)
1194          ins = m_st_64(srcdest, 0);
1195       else if (bitsize <= 128)
1196          ins = m_st_128(srcdest, 0);
1197       else
1198          unreachable("Invalid global store size");
1199 
1200       mir_set_intr_mask(instr, &ins, is_read);
1201    }
1202 
1203    mir_set_offset(ctx, &ins, offset, seg);
1204 
1205    /* Set a valid swizzle for masked out components */
1206    assert(ins.mask);
1207    unsigned first_component = __builtin_ffs(ins.mask) - 1;
1208 
1209    for (unsigned i = 0; i < ARRAY_SIZE(ins.swizzle[0]); ++i) {
1210       if (!(ins.mask & (1 << i)))
1211          ins.swizzle[0][i] = first_component;
1212    }
1213 
1214    emit_mir_instruction(ctx, ins);
1215 }
1216 
1217 static midgard_load_store_op
translate_atomic_op(nir_atomic_op op)1218 translate_atomic_op(nir_atomic_op op)
1219 {
1220    /* clang-format off */
1221    switch (op) {
1222    case nir_atomic_op_xchg:    return midgard_op_atomic_xchg;
1223    case nir_atomic_op_cmpxchg: return midgard_op_atomic_cmpxchg;
1224    case nir_atomic_op_iadd:    return midgard_op_atomic_add;
1225    case nir_atomic_op_iand:    return midgard_op_atomic_and;
1226    case nir_atomic_op_imax:    return midgard_op_atomic_imax;
1227    case nir_atomic_op_imin:    return midgard_op_atomic_imin;
1228    case nir_atomic_op_ior:     return midgard_op_atomic_or;
1229    case nir_atomic_op_umax:    return midgard_op_atomic_umax;
1230    case nir_atomic_op_umin:    return midgard_op_atomic_umin;
1231    case nir_atomic_op_ixor:    return midgard_op_atomic_xor;
1232    default: unreachable("Unexpected atomic");
1233    }
1234    /* clang-format on */
1235 }
1236 
1237 /* Emit an atomic to shared memory or global memory. */
1238 static void
emit_atomic(compiler_context * ctx,nir_intrinsic_instr * instr)1239 emit_atomic(compiler_context *ctx, nir_intrinsic_instr *instr)
1240 {
1241    midgard_load_store_op op =
1242       translate_atomic_op(nir_intrinsic_atomic_op(instr));
1243 
1244    nir_alu_type type =
1245       (op == midgard_op_atomic_imin || op == midgard_op_atomic_imax)
1246          ? nir_type_int
1247          : nir_type_uint;
1248 
1249    bool is_shared = (instr->intrinsic == nir_intrinsic_shared_atomic) ||
1250                     (instr->intrinsic == nir_intrinsic_shared_atomic_swap);
1251 
1252    unsigned dest = nir_def_index(&instr->def);
1253    unsigned val = nir_src_index(ctx, &instr->src[1]);
1254    unsigned bitsize = nir_src_bit_size(instr->src[1]);
1255    emit_explicit_constant(ctx, val);
1256 
1257    midgard_instruction ins = {
1258       .type = TAG_LOAD_STORE_4,
1259       .mask = 0xF,
1260       .dest = dest,
1261       .src = {~0, ~0, ~0, val},
1262       .src_types = {0, 0, 0, type | bitsize},
1263       .op = op,
1264    };
1265 
1266    nir_src *src_offset = nir_get_io_offset_src(instr);
1267 
1268    if (op == midgard_op_atomic_cmpxchg) {
1269       unsigned xchg_val = nir_src_index(ctx, &instr->src[2]);
1270       emit_explicit_constant(ctx, xchg_val);
1271 
1272       ins.src[2] = val;
1273       ins.src_types[2] = type | bitsize;
1274       ins.src[3] = xchg_val;
1275 
1276       if (is_shared) {
1277          ins.load_store.arg_reg = REGISTER_LDST_LOCAL_STORAGE_PTR;
1278          ins.load_store.arg_comp = COMPONENT_Z;
1279          ins.load_store.bitsize_toggle = true;
1280       } else {
1281          for (unsigned i = 0; i < 2; ++i)
1282             ins.swizzle[1][i] = i;
1283 
1284          ins.src[1] = nir_src_index(ctx, src_offset);
1285          ins.src_types[1] = nir_type_uint64;
1286       }
1287    } else
1288       mir_set_offset(ctx, &ins, src_offset,
1289                      is_shared ? LDST_SHARED : LDST_GLOBAL);
1290 
1291    mir_set_intr_mask(&instr->instr, &ins, true);
1292 
1293    emit_mir_instruction(ctx, ins);
1294 }
1295 
1296 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)1297 emit_varying_read(compiler_context *ctx, unsigned dest, unsigned offset,
1298                   unsigned nr_comp, unsigned component,
1299                   nir_src *indirect_offset, nir_alu_type type, bool flat)
1300 {
1301    midgard_instruction ins = m_ld_vary_32(dest, PACK_LDST_ATTRIB_OFS(offset));
1302    ins.mask = mask_of(nr_comp);
1303    ins.dest_type = type;
1304 
1305    if (type == nir_type_float16) {
1306       /* Ensure we are aligned so we can pack it later */
1307       ins.mask = mask_of(ALIGN_POT(nr_comp, 2));
1308    }
1309 
1310    for (unsigned i = 0; i < ARRAY_SIZE(ins.swizzle[0]); ++i)
1311       ins.swizzle[0][i] = MIN2(i + component, COMPONENT_W);
1312 
1313    midgard_varying_params p = {
1314       .flat_shading = flat,
1315       .perspective_correction = 1,
1316       .interpolate_sample = true,
1317    };
1318    midgard_pack_varying_params(&ins.load_store, p);
1319 
1320    if (indirect_offset) {
1321       ins.src[2] = nir_src_index(ctx, indirect_offset);
1322       ins.src_types[2] = nir_type_uint32;
1323    } else
1324       ins.load_store.index_reg = REGISTER_LDST_ZERO;
1325 
1326    ins.load_store.arg_reg = REGISTER_LDST_ZERO;
1327    ins.load_store.index_format = midgard_index_address_u32;
1328 
1329    /* For flat shading, for GPUs supporting auto32, we always use .u32 and
1330     * require 32-bit mode. For smooth shading, we use the appropriate
1331     * floating-point type.
1332     *
1333     * This could be optimized, but it makes it easy to check correctness.
1334     */
1335    if (ctx->quirks & MIDGARD_NO_AUTO32) {
1336       switch (type) {
1337       case nir_type_uint32:
1338       case nir_type_bool32:
1339          ins.op = midgard_op_ld_vary_32u;
1340          break;
1341       case nir_type_int32:
1342          ins.op = midgard_op_ld_vary_32i;
1343          break;
1344       case nir_type_float32:
1345          ins.op = midgard_op_ld_vary_32;
1346          break;
1347       case nir_type_float16:
1348          ins.op = midgard_op_ld_vary_16;
1349          break;
1350       default:
1351          unreachable("Attempted to load unknown type");
1352          break;
1353       }
1354    } else if (flat) {
1355       assert(nir_alu_type_get_type_size(type) == 32);
1356       ins.op = midgard_op_ld_vary_32u;
1357    } else {
1358       assert(nir_alu_type_get_base_type(type) == nir_type_float);
1359 
1360       ins.op = (nir_alu_type_get_type_size(type) == 32) ? midgard_op_ld_vary_32
1361                                                         : midgard_op_ld_vary_16;
1362    }
1363 
1364    emit_mir_instruction(ctx, ins);
1365 }
1366 
1367 static midgard_instruction
emit_image_op(compiler_context * ctx,nir_intrinsic_instr * instr)1368 emit_image_op(compiler_context *ctx, nir_intrinsic_instr *instr)
1369 {
1370    enum glsl_sampler_dim dim = nir_intrinsic_image_dim(instr);
1371    unsigned nr_dim = glsl_get_sampler_dim_coordinate_components(dim);
1372    bool is_array = nir_intrinsic_image_array(instr);
1373    bool is_store = instr->intrinsic == nir_intrinsic_image_store;
1374 
1375    assert(dim != GLSL_SAMPLER_DIM_MS && "MSAA'd image not lowered");
1376 
1377    unsigned coord_reg = nir_src_index(ctx, &instr->src[1]);
1378    emit_explicit_constant(ctx, coord_reg);
1379 
1380    nir_src *index = &instr->src[0];
1381    bool is_direct = nir_src_is_const(*index);
1382 
1383    /* For image opcodes, address is used as an index into the attribute
1384     * descriptor */
1385    unsigned address = is_direct ? nir_src_as_uint(*index) : 0;
1386 
1387    midgard_instruction ins;
1388    if (is_store) { /* emit st_image_* */
1389       unsigned val = nir_src_index(ctx, &instr->src[3]);
1390       emit_explicit_constant(ctx, val);
1391 
1392       nir_alu_type type = nir_intrinsic_src_type(instr);
1393       ins = st_image(type, val, PACK_LDST_ATTRIB_OFS(address));
1394       nir_alu_type base_type = nir_alu_type_get_base_type(type);
1395       ins.src_types[0] = base_type | nir_src_bit_size(instr->src[3]);
1396    } else if (instr->intrinsic == nir_intrinsic_image_texel_address) {
1397       ins =
1398          m_lea_image(nir_def_index(&instr->def), PACK_LDST_ATTRIB_OFS(address));
1399       ins.mask = mask_of(2); /* 64-bit memory address */
1400    } else {                  /* emit ld_image_* */
1401       nir_alu_type type = nir_intrinsic_dest_type(instr);
1402       ins = ld_image(type, nir_def_index(&instr->def),
1403                      PACK_LDST_ATTRIB_OFS(address));
1404       ins.mask = mask_of(nir_intrinsic_dest_components(instr));
1405       ins.dest_type = type;
1406    }
1407 
1408    /* Coord reg */
1409    ins.src[1] = coord_reg;
1410    ins.src_types[1] = nir_type_uint16;
1411    if (nr_dim == 3 || is_array) {
1412       ins.load_store.bitsize_toggle = true;
1413    }
1414 
1415    /* Image index reg */
1416    if (!is_direct) {
1417       ins.src[2] = nir_src_index(ctx, index);
1418       ins.src_types[2] = nir_type_uint32;
1419    } else
1420       ins.load_store.index_reg = REGISTER_LDST_ZERO;
1421 
1422    emit_mir_instruction(ctx, ins);
1423 
1424    return ins;
1425 }
1426 
1427 static void
emit_attr_read(compiler_context * ctx,unsigned dest,unsigned offset,unsigned nr_comp,nir_alu_type t)1428 emit_attr_read(compiler_context *ctx, unsigned dest, unsigned offset,
1429                unsigned nr_comp, nir_alu_type t)
1430 {
1431    midgard_instruction ins = m_ld_attr_32(dest, PACK_LDST_ATTRIB_OFS(offset));
1432    ins.load_store.arg_reg = REGISTER_LDST_ZERO;
1433    ins.load_store.index_reg = REGISTER_LDST_ZERO;
1434    ins.mask = mask_of(nr_comp);
1435 
1436    /* Use the type appropriate load */
1437    switch (t) {
1438    case nir_type_uint:
1439    case nir_type_bool:
1440       ins.op = midgard_op_ld_attr_32u;
1441       break;
1442    case nir_type_int:
1443       ins.op = midgard_op_ld_attr_32i;
1444       break;
1445    case nir_type_float:
1446       ins.op = midgard_op_ld_attr_32;
1447       break;
1448    default:
1449       unreachable("Attempted to load unknown type");
1450       break;
1451    }
1452 
1453    emit_mir_instruction(ctx, ins);
1454 }
1455 
1456 static unsigned
compute_builtin_arg(nir_intrinsic_op op)1457 compute_builtin_arg(nir_intrinsic_op op)
1458 {
1459    switch (op) {
1460    case nir_intrinsic_load_workgroup_id:
1461       return REGISTER_LDST_GROUP_ID;
1462    case nir_intrinsic_load_local_invocation_id:
1463       return REGISTER_LDST_LOCAL_THREAD_ID;
1464    case nir_intrinsic_load_global_invocation_id:
1465       return REGISTER_LDST_GLOBAL_THREAD_ID;
1466    default:
1467       unreachable("Invalid compute paramater loaded");
1468    }
1469 }
1470 
1471 static void
emit_fragment_store(compiler_context * ctx,unsigned src,unsigned src_z,unsigned src_s,enum midgard_rt_id rt,unsigned sample_iter)1472 emit_fragment_store(compiler_context *ctx, unsigned src, unsigned src_z,
1473                     unsigned src_s, enum midgard_rt_id rt, unsigned sample_iter)
1474 {
1475    assert(rt < ARRAY_SIZE(ctx->writeout_branch));
1476    assert(sample_iter < ARRAY_SIZE(ctx->writeout_branch[0]));
1477 
1478    midgard_instruction *br = ctx->writeout_branch[rt][sample_iter];
1479 
1480    assert(!br);
1481 
1482    emit_explicit_constant(ctx, src);
1483 
1484    struct midgard_instruction ins = v_branch(false, false);
1485 
1486    bool depth_only = (rt == MIDGARD_ZS_RT);
1487 
1488    ins.writeout = depth_only ? 0 : PAN_WRITEOUT_C;
1489 
1490    /* Add dependencies */
1491    ins.src[0] = src;
1492    ins.src_types[0] = nir_type_uint32;
1493 
1494    if (depth_only)
1495       ins.constants.u32[0] = 0xFF;
1496    else
1497       ins.constants.u32[0] = ((rt - MIDGARD_COLOR_RT0) << 8) | sample_iter;
1498 
1499    for (int i = 0; i < 4; ++i)
1500       ins.swizzle[0][i] = i;
1501 
1502    if (~src_z) {
1503       emit_explicit_constant(ctx, src_z);
1504       ins.src[2] = src_z;
1505       ins.src_types[2] = nir_type_uint32;
1506       ins.writeout |= PAN_WRITEOUT_Z;
1507    }
1508    if (~src_s) {
1509       emit_explicit_constant(ctx, src_s);
1510       ins.src[3] = src_s;
1511       ins.src_types[3] = nir_type_uint32;
1512       ins.writeout |= PAN_WRITEOUT_S;
1513    }
1514 
1515    /* Emit the branch */
1516    br = emit_mir_instruction(ctx, ins);
1517    schedule_barrier(ctx);
1518    ctx->writeout_branch[rt][sample_iter] = br;
1519 
1520    /* Push our current location = current block count - 1 = where we'll
1521     * jump to. Maybe a bit too clever for my own good */
1522 
1523    br->branch.target_block = ctx->block_count - 1;
1524 }
1525 
1526 static void
emit_compute_builtin(compiler_context * ctx,nir_intrinsic_instr * instr)1527 emit_compute_builtin(compiler_context *ctx, nir_intrinsic_instr *instr)
1528 {
1529    unsigned reg = nir_def_index(&instr->def);
1530    midgard_instruction ins = m_ldst_mov(reg, 0);
1531    ins.mask = mask_of(3);
1532    ins.swizzle[0][3] = COMPONENT_X; /* xyzx */
1533    ins.load_store.arg_reg = compute_builtin_arg(instr->intrinsic);
1534    emit_mir_instruction(ctx, ins);
1535 }
1536 
1537 static unsigned
vertex_builtin_arg(nir_intrinsic_op op)1538 vertex_builtin_arg(nir_intrinsic_op op)
1539 {
1540    switch (op) {
1541    case nir_intrinsic_load_raw_vertex_id_pan:
1542       return PAN_VERTEX_ID;
1543    case nir_intrinsic_load_instance_id:
1544       return PAN_INSTANCE_ID;
1545    default:
1546       unreachable("Invalid vertex builtin");
1547    }
1548 }
1549 
1550 static void
emit_vertex_builtin(compiler_context * ctx,nir_intrinsic_instr * instr)1551 emit_vertex_builtin(compiler_context *ctx, nir_intrinsic_instr *instr)
1552 {
1553    unsigned reg = nir_def_index(&instr->def);
1554    emit_attr_read(ctx, reg, vertex_builtin_arg(instr->intrinsic), 1,
1555                   nir_type_int);
1556 }
1557 
1558 static void
emit_special(compiler_context * ctx,nir_intrinsic_instr * instr,unsigned idx)1559 emit_special(compiler_context *ctx, nir_intrinsic_instr *instr, unsigned idx)
1560 {
1561    unsigned reg = nir_def_index(&instr->def);
1562 
1563    midgard_instruction ld = m_ld_tilebuffer_raw(reg, 0);
1564    ld.op = midgard_op_ld_special_32u;
1565    ld.load_store.signed_offset = PACK_LDST_SELECTOR_OFS(idx);
1566    ld.load_store.index_reg = REGISTER_LDST_ZERO;
1567 
1568    for (int i = 0; i < 4; ++i)
1569       ld.swizzle[0][i] = COMPONENT_X;
1570 
1571    emit_mir_instruction(ctx, ld);
1572 }
1573 
1574 static void
emit_control_barrier(compiler_context * ctx)1575 emit_control_barrier(compiler_context *ctx)
1576 {
1577    midgard_instruction ins = {
1578       .type = TAG_TEXTURE_4,
1579       .dest = ~0,
1580       .src = {~0, ~0, ~0, ~0},
1581       .op = midgard_tex_op_barrier,
1582    };
1583 
1584    emit_mir_instruction(ctx, ins);
1585 }
1586 
1587 static uint8_t
output_load_rt_addr(compiler_context * ctx,nir_intrinsic_instr * instr)1588 output_load_rt_addr(compiler_context *ctx, nir_intrinsic_instr *instr)
1589 {
1590    unsigned loc = nir_intrinsic_io_semantics(instr).location;
1591 
1592    if (loc >= FRAG_RESULT_DATA0)
1593       return loc - FRAG_RESULT_DATA0;
1594 
1595    if (loc == FRAG_RESULT_DEPTH)
1596       return 0x1F;
1597    if (loc == FRAG_RESULT_STENCIL)
1598       return 0x1E;
1599 
1600    unreachable("Invalid RT to load from");
1601 }
1602 
1603 static void
emit_intrinsic(compiler_context * ctx,nir_intrinsic_instr * instr)1604 emit_intrinsic(compiler_context *ctx, nir_intrinsic_instr *instr)
1605 {
1606    unsigned offset = 0, reg;
1607 
1608    switch (instr->intrinsic) {
1609    case nir_intrinsic_decl_reg:
1610    case nir_intrinsic_store_reg:
1611       /* Always fully consumed */
1612       break;
1613 
1614    case nir_intrinsic_load_reg: {
1615       /* NIR guarantees that, for typical isel, this will always be fully
1616        * consumed. However, we also do our own nir_scalar chasing for
1617        * address arithmetic, bypassing the source chasing helpers. So we can end
1618        * up with unconsumed load_register instructions. Translate them here. 99%
1619        * of the time, these moves will be DCE'd away.
1620        */
1621       nir_def *handle = instr->src[0].ssa;
1622 
1623       midgard_instruction ins =
1624          v_mov(nir_reg_index(handle), nir_def_index(&instr->def));
1625 
1626       ins.dest_type = ins.src_types[1] = nir_type_uint | instr->def.bit_size;
1627 
1628       ins.mask = BITFIELD_MASK(instr->def.num_components);
1629       emit_mir_instruction(ctx, ins);
1630       break;
1631    }
1632 
1633    case nir_intrinsic_terminate_if:
1634    case nir_intrinsic_terminate: {
1635       bool conditional = instr->intrinsic == nir_intrinsic_terminate_if;
1636       struct midgard_instruction discard = v_branch(conditional, false);
1637       discard.branch.target_type = TARGET_DISCARD;
1638 
1639       if (conditional) {
1640          discard.src[0] = nir_src_index(ctx, &instr->src[0]);
1641          discard.src_types[0] = nir_type_uint32;
1642       }
1643 
1644       emit_mir_instruction(ctx, discard);
1645       schedule_barrier(ctx);
1646 
1647       break;
1648    }
1649 
1650    case nir_intrinsic_image_load:
1651    case nir_intrinsic_image_store:
1652    case nir_intrinsic_image_texel_address:
1653       emit_image_op(ctx, instr);
1654       break;
1655 
1656    case nir_intrinsic_load_ubo:
1657    case nir_intrinsic_load_global:
1658    case nir_intrinsic_load_global_constant:
1659    case nir_intrinsic_load_shared:
1660    case nir_intrinsic_load_scratch:
1661    case nir_intrinsic_load_input:
1662    case nir_intrinsic_load_interpolated_input: {
1663       bool is_ubo = instr->intrinsic == nir_intrinsic_load_ubo;
1664       bool is_global = instr->intrinsic == nir_intrinsic_load_global ||
1665                        instr->intrinsic == nir_intrinsic_load_global_constant;
1666       bool is_shared = instr->intrinsic == nir_intrinsic_load_shared;
1667       bool is_scratch = instr->intrinsic == nir_intrinsic_load_scratch;
1668       bool is_flat = instr->intrinsic == nir_intrinsic_load_input;
1669       bool is_interp =
1670          instr->intrinsic == nir_intrinsic_load_interpolated_input;
1671 
1672       /* Get the base type of the intrinsic */
1673       /* TODO: Infer type? Does it matter? */
1674       nir_alu_type t = (is_interp) ? nir_type_float
1675                        : (is_flat) ? nir_intrinsic_dest_type(instr)
1676                                    : nir_type_uint;
1677 
1678       t = nir_alu_type_get_base_type(t);
1679 
1680       if (!(is_ubo || is_global || is_scratch)) {
1681          offset = nir_intrinsic_base(instr);
1682       }
1683 
1684       unsigned nr_comp = nir_intrinsic_dest_components(instr);
1685 
1686       nir_src *src_offset = nir_get_io_offset_src(instr);
1687 
1688       bool direct = nir_src_is_const(*src_offset);
1689       nir_src *indirect_offset = direct ? NULL : src_offset;
1690 
1691       if (direct)
1692          offset += nir_src_as_uint(*src_offset);
1693 
1694       /* We may need to apply a fractional offset */
1695       int component =
1696          (is_flat || is_interp) ? nir_intrinsic_component(instr) : 0;
1697       reg = nir_def_index(&instr->def);
1698 
1699       if (is_ubo) {
1700          nir_src index = instr->src[0];
1701 
1702          /* TODO: Is indirect block number possible? */
1703          assert(nir_src_is_const(index));
1704 
1705          uint32_t uindex = nir_src_as_uint(index);
1706          emit_ubo_read(ctx, &instr->instr, reg, offset, indirect_offset, 0,
1707                        uindex, nr_comp);
1708       } else if (is_global || is_shared || is_scratch) {
1709          unsigned seg =
1710             is_global ? LDST_GLOBAL : (is_shared ? LDST_SHARED : LDST_SCRATCH);
1711          emit_global(ctx, &instr->instr, true, reg, src_offset, seg);
1712       } else if (ctx->stage == MESA_SHADER_FRAGMENT && !ctx->inputs->is_blend) {
1713          emit_varying_read(ctx, reg, offset, nr_comp, component,
1714                            indirect_offset, t | instr->def.bit_size, is_flat);
1715       } else if (ctx->inputs->is_blend) {
1716          /* ctx->blend_input will be precoloured to r0/r2, where
1717           * the input is preloaded */
1718 
1719          unsigned *input = offset ? &ctx->blend_src1 : &ctx->blend_input;
1720 
1721          if (*input == ~0)
1722             *input = reg;
1723          else
1724             emit_mir_instruction(ctx, v_mov(*input, reg));
1725       } else if (ctx->stage == MESA_SHADER_VERTEX) {
1726          emit_attr_read(ctx, reg, offset, nr_comp, t);
1727       } else {
1728          unreachable("Unknown load");
1729       }
1730 
1731       break;
1732    }
1733 
1734    /* Handled together with load_interpolated_input */
1735    case nir_intrinsic_load_barycentric_pixel:
1736    case nir_intrinsic_load_barycentric_centroid:
1737    case nir_intrinsic_load_barycentric_sample:
1738       break;
1739 
1740       /* Reads 128-bit value raw off the tilebuffer during blending, tasty */
1741 
1742    case nir_intrinsic_load_raw_output_pan: {
1743       reg = nir_def_index(&instr->def);
1744 
1745       /* T720 and below use different blend opcodes with slightly
1746        * different semantics than T760 and up */
1747 
1748       midgard_instruction ld = m_ld_tilebuffer_raw(reg, 0);
1749 
1750       unsigned target = output_load_rt_addr(ctx, instr);
1751       ld.load_store.index_comp = target & 0x3;
1752       ld.load_store.index_reg = target >> 2;
1753 
1754       if (nir_src_is_const(instr->src[0])) {
1755          unsigned sample = nir_src_as_uint(instr->src[0]);
1756          ld.load_store.arg_comp = sample & 0x3;
1757          ld.load_store.arg_reg = sample >> 2;
1758       } else {
1759          /* Enable sample index via register. */
1760          ld.load_store.signed_offset |= 1;
1761          ld.src[1] = nir_src_index(ctx, &instr->src[0]);
1762          ld.src_types[1] = nir_type_int32;
1763       }
1764 
1765       if (ctx->quirks & MIDGARD_OLD_BLEND) {
1766          ld.op = midgard_op_ld_special_32u;
1767          ld.load_store.signed_offset = PACK_LDST_SELECTOR_OFS(16);
1768          ld.load_store.index_reg = REGISTER_LDST_ZERO;
1769       }
1770 
1771       emit_mir_instruction(ctx, ld);
1772       break;
1773    }
1774 
1775    case nir_intrinsic_load_output: {
1776       reg = nir_def_index(&instr->def);
1777 
1778       unsigned bits = instr->def.bit_size;
1779 
1780       midgard_instruction ld;
1781       if (bits == 16)
1782          ld = m_ld_tilebuffer_16f(reg, 0);
1783       else
1784          ld = m_ld_tilebuffer_32f(reg, 0);
1785 
1786       unsigned index = output_load_rt_addr(ctx, instr);
1787       ld.load_store.index_comp = index & 0x3;
1788       ld.load_store.index_reg = index >> 2;
1789 
1790       for (unsigned c = 4; c < 16; ++c)
1791          ld.swizzle[0][c] = 0;
1792 
1793       if (ctx->quirks & MIDGARD_OLD_BLEND) {
1794          if (bits == 16)
1795             ld.op = midgard_op_ld_special_16f;
1796          else
1797             ld.op = midgard_op_ld_special_32f;
1798          ld.load_store.signed_offset = PACK_LDST_SELECTOR_OFS(1);
1799          ld.load_store.index_reg = REGISTER_LDST_ZERO;
1800       }
1801 
1802       emit_mir_instruction(ctx, ld);
1803       break;
1804    }
1805 
1806    case nir_intrinsic_store_output:
1807    case nir_intrinsic_store_combined_output_pan:
1808       assert(nir_src_is_const(instr->src[1]) && "no indirect outputs");
1809 
1810       reg = nir_src_index(ctx, &instr->src[0]);
1811 
1812       if (ctx->stage == MESA_SHADER_FRAGMENT) {
1813          bool combined =
1814             instr->intrinsic == nir_intrinsic_store_combined_output_pan;
1815 
1816          enum midgard_rt_id rt;
1817 
1818          unsigned reg_z = ~0, reg_s = ~0, reg_2 = ~0;
1819          unsigned writeout = PAN_WRITEOUT_C;
1820          if (combined) {
1821             writeout = nir_intrinsic_component(instr);
1822             if (writeout & PAN_WRITEOUT_Z)
1823                reg_z = nir_src_index(ctx, &instr->src[2]);
1824             if (writeout & PAN_WRITEOUT_S)
1825                reg_s = nir_src_index(ctx, &instr->src[3]);
1826             if (writeout & PAN_WRITEOUT_2)
1827                reg_2 = nir_src_index(ctx, &instr->src[4]);
1828          }
1829 
1830          if (writeout & PAN_WRITEOUT_C) {
1831             nir_io_semantics sem = nir_intrinsic_io_semantics(instr);
1832 
1833             rt = MIDGARD_COLOR_RT0 + (sem.location - FRAG_RESULT_DATA0);
1834          } else {
1835             rt = MIDGARD_ZS_RT;
1836          }
1837 
1838          /* Dual-source blend writeout is done by leaving the
1839           * value in r2 for the blend shader to use. */
1840          if (~reg_2) {
1841             emit_explicit_constant(ctx, reg_2);
1842 
1843             unsigned out = make_compiler_temp(ctx);
1844 
1845             midgard_instruction ins = v_mov(reg_2, out);
1846             emit_mir_instruction(ctx, ins);
1847 
1848             ctx->blend_src1 = out;
1849          }
1850 
1851          emit_fragment_store(ctx, reg, reg_z, reg_s, rt, 0);
1852       } else if (ctx->stage == MESA_SHADER_VERTEX) {
1853          assert(instr->intrinsic == nir_intrinsic_store_output);
1854 
1855          /* We should have been vectorized, though we don't
1856           * currently check that st_vary is emitted only once
1857           * per slot (this is relevant, since there's not a mask
1858           * parameter available on the store [set to 0 by the
1859           * blob]). We do respect the component by adjusting the
1860           * swizzle. If this is a constant source, we'll need to
1861           * emit that explicitly. */
1862 
1863          emit_explicit_constant(ctx, reg);
1864 
1865          offset = nir_intrinsic_base(instr) + nir_src_as_uint(instr->src[1]);
1866 
1867          unsigned dst_component = nir_intrinsic_component(instr);
1868          unsigned nr_comp = nir_src_num_components(instr->src[0]);
1869 
1870          /* ABI: Format controlled by the attribute descriptor.
1871           * This simplifies flat shading, although it prevents
1872           * certain (unimplemented) 16-bit optimizations.
1873           *
1874           * In particular, it lets the driver handle internal
1875           * TGSI shaders that set flat in the VS but smooth in
1876           * the FS. This matches our handling on Bifrost.
1877           */
1878          bool auto32 = true;
1879          assert(nir_alu_type_get_type_size(nir_intrinsic_src_type(instr)) ==
1880                 32);
1881 
1882          /* ABI: varyings in the secondary attribute table */
1883          bool secondary_table = true;
1884 
1885          midgard_instruction st =
1886             m_st_vary_32(reg, PACK_LDST_ATTRIB_OFS(offset));
1887          st.load_store.arg_reg = REGISTER_LDST_ZERO;
1888          st.load_store.index_reg = REGISTER_LDST_ZERO;
1889 
1890          /* Attribute instruction uses these 2-bits for the
1891           * a32 and table bits, pack this specially.
1892           */
1893          st.load_store.index_format =
1894             (auto32 ? (1 << 0) : 0) | (secondary_table ? (1 << 1) : 0);
1895 
1896          /* nir_intrinsic_component(store_intr) encodes the
1897           * destination component start. Source component offset
1898           * adjustment is taken care of in
1899           * install_registers_instr(), when offset_swizzle() is
1900           * called.
1901           */
1902          unsigned src_component = COMPONENT_X;
1903 
1904          assert(nr_comp > 0);
1905          for (unsigned i = 0; i < ARRAY_SIZE(st.swizzle); ++i) {
1906             st.swizzle[0][i] = src_component;
1907             if (i >= dst_component && i < dst_component + nr_comp - 1)
1908                src_component++;
1909          }
1910 
1911          emit_mir_instruction(ctx, st);
1912       } else {
1913          unreachable("Unknown store");
1914       }
1915 
1916       break;
1917 
1918    /* Special case of store_output for lowered blend shaders */
1919    case nir_intrinsic_store_raw_output_pan: {
1920       assert(ctx->stage == MESA_SHADER_FRAGMENT);
1921       reg = nir_src_index(ctx, &instr->src[0]);
1922 
1923       nir_io_semantics sem = nir_intrinsic_io_semantics(instr);
1924       assert(sem.location >= FRAG_RESULT_DATA0);
1925       unsigned rt = sem.location - FRAG_RESULT_DATA0;
1926 
1927       emit_fragment_store(ctx, reg, ~0, ~0, rt + MIDGARD_COLOR_RT0,
1928                           nir_intrinsic_base(instr));
1929       break;
1930    }
1931 
1932    case nir_intrinsic_store_global:
1933    case nir_intrinsic_store_shared:
1934    case nir_intrinsic_store_scratch:
1935       reg = nir_src_index(ctx, &instr->src[0]);
1936       emit_explicit_constant(ctx, reg);
1937 
1938       unsigned seg;
1939       if (instr->intrinsic == nir_intrinsic_store_global)
1940          seg = LDST_GLOBAL;
1941       else if (instr->intrinsic == nir_intrinsic_store_shared)
1942          seg = LDST_SHARED;
1943       else
1944          seg = LDST_SCRATCH;
1945 
1946       emit_global(ctx, &instr->instr, false, reg, &instr->src[1], seg);
1947       break;
1948 
1949    case nir_intrinsic_load_workgroup_id:
1950    case nir_intrinsic_load_local_invocation_id:
1951    case nir_intrinsic_load_global_invocation_id:
1952       emit_compute_builtin(ctx, instr);
1953       break;
1954 
1955    case nir_intrinsic_load_raw_vertex_id_pan:
1956       ctx->info->midgard.vs.reads_raw_vertex_id = true;
1957       FALLTHROUGH;
1958    case nir_intrinsic_load_instance_id:
1959       emit_vertex_builtin(ctx, instr);
1960       break;
1961 
1962    case nir_intrinsic_load_sample_mask_in:
1963       emit_special(ctx, instr, 96);
1964       break;
1965 
1966    case nir_intrinsic_load_sample_id:
1967       emit_special(ctx, instr, 97);
1968       break;
1969 
1970    case nir_intrinsic_barrier:
1971       if (nir_intrinsic_execution_scope(instr) != SCOPE_NONE) {
1972          schedule_barrier(ctx);
1973          emit_control_barrier(ctx);
1974          schedule_barrier(ctx);
1975       } else if (nir_intrinsic_memory_scope(instr) != SCOPE_NONE) {
1976          /* Midgard doesn't seem to want special handling, though we do need to
1977           * take care when scheduling to avoid incorrect reordering.
1978           *
1979           * Note this is an "else if" since the handling for the execution scope
1980           * case already covers the case when both scopes are present.
1981           */
1982          schedule_barrier(ctx);
1983       }
1984       break;
1985 
1986    case nir_intrinsic_shared_atomic:
1987    case nir_intrinsic_shared_atomic_swap:
1988    case nir_intrinsic_global_atomic:
1989    case nir_intrinsic_global_atomic_swap:
1990       emit_atomic(ctx, instr);
1991       break;
1992 
1993    case nir_intrinsic_ddx:
1994    case nir_intrinsic_ddy:
1995       midgard_emit_derivatives(ctx, instr);
1996       break;
1997 
1998    default:
1999       fprintf(stderr, "Unhandled intrinsic %s\n",
2000               nir_intrinsic_infos[instr->intrinsic].name);
2001       assert(0);
2002       break;
2003    }
2004 }
2005 
2006 /* Returns dimension with 0 special casing cubemaps */
2007 static unsigned
midgard_tex_format(enum glsl_sampler_dim dim)2008 midgard_tex_format(enum glsl_sampler_dim dim)
2009 {
2010    switch (dim) {
2011    case GLSL_SAMPLER_DIM_1D:
2012    case GLSL_SAMPLER_DIM_BUF:
2013       return 1;
2014 
2015    case GLSL_SAMPLER_DIM_2D:
2016    case GLSL_SAMPLER_DIM_MS:
2017    case GLSL_SAMPLER_DIM_EXTERNAL:
2018    case GLSL_SAMPLER_DIM_RECT:
2019       return 2;
2020 
2021    case GLSL_SAMPLER_DIM_3D:
2022       return 3;
2023 
2024    case GLSL_SAMPLER_DIM_CUBE:
2025       return 0;
2026 
2027    default:
2028       unreachable("Unknown sampler dim type");
2029    }
2030 }
2031 
2032 /* Tries to attach an explicit LOD or bias as a constant. Returns whether this
2033  * was successful */
2034 
2035 static bool
pan_attach_constant_bias(compiler_context * ctx,nir_src lod,midgard_texture_word * word)2036 pan_attach_constant_bias(compiler_context *ctx, nir_src lod,
2037                          midgard_texture_word *word)
2038 {
2039    /* To attach as constant, it has to *be* constant */
2040 
2041    if (!nir_src_is_const(lod))
2042       return false;
2043 
2044    float f = nir_src_as_float(lod);
2045 
2046    /* Break into fixed-point */
2047    signed lod_int = f;
2048    float lod_frac = f - lod_int;
2049 
2050    /* Carry over negative fractions */
2051    if (lod_frac < 0.0) {
2052       lod_int--;
2053       lod_frac += 1.0;
2054    }
2055 
2056    /* Encode */
2057    word->bias = float_to_ubyte(lod_frac);
2058    word->bias_int = lod_int;
2059 
2060    return true;
2061 }
2062 
2063 static enum mali_texture_mode
mdg_texture_mode(nir_tex_instr * instr)2064 mdg_texture_mode(nir_tex_instr *instr)
2065 {
2066    if (instr->op == nir_texop_tg4 && instr->is_shadow)
2067       return TEXTURE_GATHER_SHADOW;
2068    else if (instr->op == nir_texop_tg4)
2069       return TEXTURE_GATHER_X + instr->component;
2070    else if (instr->is_shadow)
2071       return TEXTURE_SHADOW;
2072    else
2073       return TEXTURE_NORMAL;
2074 }
2075 
2076 static void
set_tex_coord(compiler_context * ctx,nir_tex_instr * instr,midgard_instruction * ins)2077 set_tex_coord(compiler_context *ctx, nir_tex_instr *instr,
2078               midgard_instruction *ins)
2079 {
2080    int coord_idx = nir_tex_instr_src_index(instr, nir_tex_src_coord);
2081 
2082    assert(coord_idx >= 0);
2083 
2084    int comparator_idx = nir_tex_instr_src_index(instr, nir_tex_src_comparator);
2085    int ms_idx = nir_tex_instr_src_index(instr, nir_tex_src_ms_index);
2086    assert(comparator_idx < 0 || ms_idx < 0);
2087    int ms_or_comparator_idx = ms_idx >= 0 ? ms_idx : comparator_idx;
2088 
2089    unsigned coords = nir_src_index(ctx, &instr->src[coord_idx].src);
2090 
2091    emit_explicit_constant(ctx, coords);
2092 
2093    ins->src_types[1] = nir_tex_instr_src_type(instr, coord_idx) |
2094                        nir_src_bit_size(instr->src[coord_idx].src);
2095 
2096    unsigned nr_comps = instr->coord_components;
2097    unsigned written_mask = 0, write_mask = 0;
2098 
2099    /* Initialize all components to coord.x which is expected to always be
2100     * present. Swizzle is updated below based on the texture dimension
2101     * and extra attributes that are packed in the coordinate argument.
2102     */
2103    for (unsigned c = 0; c < MIR_VEC_COMPONENTS; c++)
2104       ins->swizzle[1][c] = COMPONENT_X;
2105 
2106    /* Shadow ref value is part of the coordinates if there's no comparator
2107     * source, in that case it's always placed in the last component.
2108     * Midgard wants the ref value in coord.z.
2109     */
2110    if (instr->is_shadow && comparator_idx < 0) {
2111       ins->swizzle[1][COMPONENT_Z] = --nr_comps;
2112       write_mask |= 1 << COMPONENT_Z;
2113    }
2114 
2115    /* The array index is the last component if there's no shadow ref value
2116     * or second last if there's one. We already decremented the number of
2117     * components to account for the shadow ref value above.
2118     * Midgard wants the array index in coord.w.
2119     */
2120    if (instr->is_array) {
2121       ins->swizzle[1][COMPONENT_W] = --nr_comps;
2122       write_mask |= 1 << COMPONENT_W;
2123    }
2124 
2125    if (instr->sampler_dim == GLSL_SAMPLER_DIM_CUBE) {
2126       /* texelFetch is undefined on samplerCube */
2127       assert(ins->op != midgard_tex_op_fetch);
2128 
2129       ins->src[1] = make_compiler_temp_reg(ctx);
2130 
2131       /* For cubemaps, we use a special ld/st op to select the face
2132        * and copy the xy into the texture register
2133        */
2134       midgard_instruction ld = m_ld_cubemap_coords(ins->src[1], 0);
2135       ld.src[1] = coords;
2136       ld.src_types[1] = ins->src_types[1];
2137       ld.mask = 0x3; /* xy */
2138       ld.load_store.bitsize_toggle = true;
2139       ld.swizzle[1][3] = COMPONENT_X;
2140       emit_mir_instruction(ctx, ld);
2141 
2142       /* We packed cube coordiates (X,Y,Z) into (X,Y), update the
2143        * written mask accordingly and decrement the number of
2144        * components
2145        */
2146       nr_comps--;
2147       written_mask |= 3;
2148    }
2149 
2150    /* Now flag tex coord components that have not been written yet */
2151    write_mask |= mask_of(nr_comps) & ~written_mask;
2152    for (unsigned c = 0; c < nr_comps; c++)
2153       ins->swizzle[1][c] = c;
2154 
2155    /* Sample index and shadow ref are expected in coord.z */
2156    if (ms_or_comparator_idx >= 0) {
2157       assert(!((write_mask | written_mask) & (1 << COMPONENT_Z)));
2158 
2159       unsigned sample_or_ref =
2160          nir_src_index(ctx, &instr->src[ms_or_comparator_idx].src);
2161 
2162       emit_explicit_constant(ctx, sample_or_ref);
2163 
2164       if (ins->src[1] == ~0)
2165          ins->src[1] = make_compiler_temp_reg(ctx);
2166 
2167       midgard_instruction mov = v_mov(sample_or_ref, ins->src[1]);
2168 
2169       for (unsigned c = 0; c < MIR_VEC_COMPONENTS; c++)
2170          mov.swizzle[1][c] = COMPONENT_X;
2171 
2172       mov.mask = 1 << COMPONENT_Z;
2173       written_mask |= 1 << COMPONENT_Z;
2174       ins->swizzle[1][COMPONENT_Z] = COMPONENT_Z;
2175       emit_mir_instruction(ctx, mov);
2176    }
2177 
2178    /* Texelfetch coordinates uses all four elements (xyz/index) regardless
2179     * of texture dimensionality, which means it's necessary to zero the
2180     * unused components to keep everything happy.
2181     */
2182    if (ins->op == midgard_tex_op_fetch && (written_mask | write_mask) != 0xF) {
2183       if (ins->src[1] == ~0)
2184          ins->src[1] = make_compiler_temp_reg(ctx);
2185 
2186       /* mov index.zw, #0, or generalized */
2187       midgard_instruction mov =
2188          v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT), ins->src[1]);
2189       mov.has_constants = true;
2190       mov.mask = (written_mask | write_mask) ^ 0xF;
2191       emit_mir_instruction(ctx, mov);
2192       for (unsigned c = 0; c < MIR_VEC_COMPONENTS; c++) {
2193          if (mov.mask & (1 << c))
2194             ins->swizzle[1][c] = c;
2195       }
2196    }
2197 
2198    if (ins->src[1] == ~0) {
2199       /* No temporary reg created, use the src coords directly */
2200       ins->src[1] = coords;
2201    } else if (write_mask) {
2202       /* Move the remaining coordinates to the temporary reg */
2203       midgard_instruction mov = v_mov(coords, ins->src[1]);
2204 
2205       for (unsigned c = 0; c < MIR_VEC_COMPONENTS; c++) {
2206          if ((1 << c) & write_mask) {
2207             mov.swizzle[1][c] = ins->swizzle[1][c];
2208             ins->swizzle[1][c] = c;
2209          } else {
2210             mov.swizzle[1][c] = COMPONENT_X;
2211          }
2212       }
2213 
2214       mov.mask = write_mask;
2215       emit_mir_instruction(ctx, mov);
2216    }
2217 }
2218 
2219 static void
emit_texop_native(compiler_context * ctx,nir_tex_instr * instr,unsigned midgard_texop)2220 emit_texop_native(compiler_context *ctx, nir_tex_instr *instr,
2221                   unsigned midgard_texop)
2222 {
2223    int texture_index = instr->texture_index;
2224    int sampler_index = instr->sampler_index;
2225 
2226    /* If txf is used, we assume there is a valid sampler bound at index 0. Use
2227     * it for txf operations, since there may be no other valid samplers. This is
2228     * a workaround: txf does not require a sampler in NIR (so sampler_index is
2229     * undefined) but we need one in the hardware. This is ABI with the driver.
2230     */
2231    if (!nir_tex_instr_need_sampler(instr))
2232       sampler_index = 0;
2233 
2234    midgard_instruction ins = {
2235       .type = TAG_TEXTURE_4,
2236       .mask = 0xF,
2237       .dest = nir_def_index(&instr->def),
2238       .src = {~0, ~0, ~0, ~0},
2239       .dest_type = instr->dest_type,
2240       .swizzle = SWIZZLE_IDENTITY_4,
2241       .outmod = midgard_outmod_none,
2242       .op = midgard_texop,
2243       .texture = {
2244          .format = midgard_tex_format(instr->sampler_dim),
2245          .texture_handle = texture_index,
2246          .sampler_handle = sampler_index,
2247          .mode = mdg_texture_mode(instr),
2248       }};
2249 
2250    if (instr->is_shadow && !instr->is_new_style_shadow &&
2251        instr->op != nir_texop_tg4)
2252       for (int i = 0; i < 4; ++i)
2253          ins.swizzle[0][i] = COMPONENT_X;
2254 
2255    for (unsigned i = 0; i < instr->num_srcs; ++i) {
2256       int index = nir_src_index(ctx, &instr->src[i].src);
2257       unsigned sz = nir_src_bit_size(instr->src[i].src);
2258       nir_alu_type T = nir_tex_instr_src_type(instr, i) | sz;
2259 
2260       switch (instr->src[i].src_type) {
2261       case nir_tex_src_coord:
2262          set_tex_coord(ctx, instr, &ins);
2263          break;
2264 
2265       case nir_tex_src_bias:
2266       case nir_tex_src_lod: {
2267          /* Try as a constant if we can */
2268 
2269          bool is_txf = midgard_texop == midgard_tex_op_fetch;
2270          if (!is_txf &&
2271              pan_attach_constant_bias(ctx, instr->src[i].src, &ins.texture))
2272             break;
2273 
2274          ins.texture.lod_register = true;
2275          ins.src[2] = index;
2276          ins.src_types[2] = T;
2277 
2278          for (unsigned c = 0; c < MIR_VEC_COMPONENTS; ++c)
2279             ins.swizzle[2][c] = COMPONENT_X;
2280 
2281          emit_explicit_constant(ctx, index);
2282 
2283          break;
2284       };
2285 
2286       case nir_tex_src_offset: {
2287          ins.texture.offset_register = true;
2288          ins.src[3] = index;
2289          ins.src_types[3] = T;
2290 
2291          for (unsigned c = 0; c < MIR_VEC_COMPONENTS; ++c)
2292             ins.swizzle[3][c] = (c > COMPONENT_Z) ? 0 : c;
2293 
2294          emit_explicit_constant(ctx, index);
2295          break;
2296       };
2297 
2298       case nir_tex_src_comparator:
2299       case nir_tex_src_ms_index:
2300          /* Nothing to do, handled in set_tex_coord() */
2301          break;
2302 
2303       default: {
2304          fprintf(stderr, "Unknown texture source type: %d\n",
2305                  instr->src[i].src_type);
2306          assert(0);
2307       }
2308       }
2309    }
2310 
2311    emit_mir_instruction(ctx, ins);
2312 }
2313 
2314 static void
emit_tex(compiler_context * ctx,nir_tex_instr * instr)2315 emit_tex(compiler_context *ctx, nir_tex_instr *instr)
2316 {
2317    switch (instr->op) {
2318    case nir_texop_tex:
2319    case nir_texop_txb:
2320       emit_texop_native(ctx, instr, midgard_tex_op_normal);
2321       break;
2322    case nir_texop_txl:
2323    case nir_texop_tg4:
2324       emit_texop_native(ctx, instr, midgard_tex_op_gradient);
2325       break;
2326    case nir_texop_txf:
2327    case nir_texop_txf_ms:
2328       emit_texop_native(ctx, instr, midgard_tex_op_fetch);
2329       break;
2330    default: {
2331       fprintf(stderr, "Unhandled texture op: %d\n", instr->op);
2332       assert(0);
2333    }
2334    }
2335 }
2336 
2337 static void
emit_jump(compiler_context * ctx,nir_jump_instr * instr)2338 emit_jump(compiler_context *ctx, nir_jump_instr *instr)
2339 {
2340    switch (instr->type) {
2341    case nir_jump_break: {
2342       /* Emit a branch out of the loop */
2343       struct midgard_instruction br = v_branch(false, false);
2344       br.branch.target_type = TARGET_BREAK;
2345       br.branch.target_break = ctx->current_loop_depth;
2346       emit_mir_instruction(ctx, br);
2347       break;
2348    }
2349 
2350    default:
2351       unreachable("Unhandled jump");
2352    }
2353 }
2354 
2355 static void
emit_instr(compiler_context * ctx,struct nir_instr * instr)2356 emit_instr(compiler_context *ctx, struct nir_instr *instr)
2357 {
2358    switch (instr->type) {
2359    case nir_instr_type_load_const:
2360       emit_load_const(ctx, nir_instr_as_load_const(instr));
2361       break;
2362 
2363    case nir_instr_type_intrinsic:
2364       emit_intrinsic(ctx, nir_instr_as_intrinsic(instr));
2365       break;
2366 
2367    case nir_instr_type_alu:
2368       emit_alu(ctx, nir_instr_as_alu(instr));
2369       break;
2370 
2371    case nir_instr_type_tex:
2372       emit_tex(ctx, nir_instr_as_tex(instr));
2373       break;
2374 
2375    case nir_instr_type_jump:
2376       emit_jump(ctx, nir_instr_as_jump(instr));
2377       break;
2378 
2379    case nir_instr_type_undef:
2380       /* Spurious */
2381       break;
2382 
2383    default:
2384       unreachable("Unhandled instruction type");
2385    }
2386 }
2387 
2388 /* ALU instructions can inline or embed constants, which decreases register
2389  * pressure and saves space. */
2390 
2391 #define CONDITIONAL_ATTACH(idx)                                                \
2392    {                                                                           \
2393       void *entry =                                                            \
2394          _mesa_hash_table_u64_search(ctx->ssa_constants, alu->src[idx] + 1);   \
2395                                                                                \
2396       if (entry) {                                                             \
2397          attach_constants(ctx, alu, entry, alu->src[idx] + 1);                 \
2398          alu->src[idx] = SSA_FIXED_REGISTER(REGISTER_CONSTANT);                \
2399       }                                                                        \
2400    }
2401 
2402 static void
inline_alu_constants(compiler_context * ctx,midgard_block * block)2403 inline_alu_constants(compiler_context *ctx, midgard_block *block)
2404 {
2405    mir_foreach_instr_in_block(block, alu) {
2406       /* Other instructions cannot inline constants */
2407       if (alu->type != TAG_ALU_4)
2408          continue;
2409       if (alu->compact_branch)
2410          continue;
2411 
2412       /* If there is already a constant here, we can do nothing */
2413       if (alu->has_constants)
2414          continue;
2415 
2416       CONDITIONAL_ATTACH(0);
2417 
2418       if (!alu->has_constants) {
2419          CONDITIONAL_ATTACH(1)
2420       } else if (!alu->inline_constant) {
2421          /* Corner case: _two_ vec4 constants, for instance with a
2422           * csel. For this case, we can only use a constant
2423           * register for one, we'll have to emit a move for the
2424           * other. */
2425 
2426          void *entry =
2427             _mesa_hash_table_u64_search(ctx->ssa_constants, alu->src[1] + 1);
2428          unsigned scratch = make_compiler_temp(ctx);
2429 
2430          if (entry) {
2431             midgard_instruction ins =
2432                v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT), scratch);
2433             attach_constants(ctx, &ins, entry, alu->src[1] + 1);
2434 
2435             /* Set the source */
2436             alu->src[1] = scratch;
2437 
2438             /* Inject us -before- the last instruction which set r31, if
2439              * possible.
2440              */
2441             midgard_instruction *first = list_first_entry(
2442                &block->base.instructions, midgard_instruction, link);
2443 
2444             if (alu == first) {
2445                mir_insert_instruction_before(ctx, alu, ins);
2446             } else {
2447                mir_insert_instruction_before(ctx, mir_prev_op(alu), ins);
2448             }
2449          }
2450       }
2451    }
2452 }
2453 
2454 unsigned
max_bitsize_for_alu(midgard_instruction * ins)2455 max_bitsize_for_alu(midgard_instruction *ins)
2456 {
2457    unsigned max_bitsize = 0;
2458    for (int i = 0; i < MIR_SRC_COUNT; i++) {
2459       if (ins->src[i] == ~0)
2460          continue;
2461       unsigned src_bitsize = nir_alu_type_get_type_size(ins->src_types[i]);
2462       max_bitsize = MAX2(src_bitsize, max_bitsize);
2463    }
2464    unsigned dst_bitsize = nir_alu_type_get_type_size(ins->dest_type);
2465    max_bitsize = MAX2(dst_bitsize, max_bitsize);
2466 
2467    /* We emulate 8-bit as 16-bit for simplicity of packing */
2468    max_bitsize = MAX2(max_bitsize, 16);
2469 
2470    /* We don't have fp16 LUTs, so we'll want to emit code like:
2471     *
2472     *      vlut.fsinr hr0, hr0
2473     *
2474     * where both input and output are 16-bit but the operation is carried
2475     * out in 32-bit
2476     */
2477 
2478    switch (ins->op) {
2479    case midgard_alu_op_fsqrt:
2480    case midgard_alu_op_frcp:
2481    case midgard_alu_op_frsqrt:
2482    case midgard_alu_op_fsinpi:
2483    case midgard_alu_op_fcospi:
2484    case midgard_alu_op_fexp2:
2485    case midgard_alu_op_flog2:
2486       max_bitsize = MAX2(max_bitsize, 32);
2487       break;
2488 
2489    default:
2490       break;
2491    }
2492 
2493    /* High implies computing at a higher bitsize, e.g umul_high of 32-bit
2494     * requires computing at 64-bit */
2495    if (midgard_is_integer_out_op(ins->op) &&
2496        ins->outmod == midgard_outmod_keephi) {
2497       max_bitsize *= 2;
2498       assert(max_bitsize <= 64);
2499    }
2500 
2501    return max_bitsize;
2502 }
2503 
2504 midgard_reg_mode
reg_mode_for_bitsize(unsigned bitsize)2505 reg_mode_for_bitsize(unsigned bitsize)
2506 {
2507    switch (bitsize) {
2508       /* use 16 pipe for 8 since we don't support vec16 yet */
2509    case 8:
2510    case 16:
2511       return midgard_reg_mode_16;
2512    case 32:
2513       return midgard_reg_mode_32;
2514    case 64:
2515       return midgard_reg_mode_64;
2516    default:
2517       unreachable("invalid bit size");
2518    }
2519 }
2520 
2521 /* Midgard supports two types of constants, embedded constants (128-bit) and
2522  * inline constants (16-bit). Sometimes, especially with scalar ops, embedded
2523  * constants can be demoted to inline constants, for space savings and
2524  * sometimes a performance boost */
2525 
2526 static void
embedded_to_inline_constant(compiler_context * ctx,midgard_block * block)2527 embedded_to_inline_constant(compiler_context *ctx, midgard_block *block)
2528 {
2529    mir_foreach_instr_in_block(block, ins) {
2530       if (!ins->has_constants)
2531          continue;
2532       if (ins->has_inline_constant)
2533          continue;
2534 
2535       unsigned max_bitsize = max_bitsize_for_alu(ins);
2536 
2537       /* We can inline 32-bit (sometimes) or 16-bit (usually) */
2538       bool is_16 = max_bitsize == 16;
2539       bool is_32 = max_bitsize == 32;
2540 
2541       if (!(is_16 || is_32))
2542          continue;
2543 
2544       /* src1 cannot be an inline constant due to encoding
2545        * restrictions. So, if possible we try to flip the arguments
2546        * in that case */
2547 
2548       int op = ins->op;
2549 
2550       if (ins->src[0] == SSA_FIXED_REGISTER(REGISTER_CONSTANT) &&
2551           alu_opcode_props[op].props & OP_COMMUTES) {
2552          mir_flip(ins);
2553       }
2554 
2555       if (ins->src[1] == SSA_FIXED_REGISTER(REGISTER_CONSTANT)) {
2556          /* Component is from the swizzle. Take a nonzero component */
2557          assert(ins->mask);
2558          unsigned first_comp = ffs(ins->mask) - 1;
2559          unsigned component = ins->swizzle[1][first_comp];
2560 
2561          /* Scale constant appropriately, if we can legally */
2562          int16_t scaled_constant = 0;
2563 
2564          if (is_16) {
2565             scaled_constant = ins->constants.u16[component];
2566          } else if (midgard_is_integer_op(op)) {
2567             scaled_constant = ins->constants.u32[component];
2568 
2569             /* Constant overflow after resize */
2570             if (scaled_constant != ins->constants.u32[component])
2571                continue;
2572          } else {
2573             float original = ins->constants.f32[component];
2574             scaled_constant = _mesa_float_to_half(original);
2575 
2576             /* Check for loss of precision. If this is
2577              * mediump, we don't care, but for a highp
2578              * shader, we need to pay attention. NIR
2579              * doesn't yet tell us which mode we're in!
2580              * Practically this prevents most constants
2581              * from being inlined, sadly. */
2582 
2583             float fp32 = _mesa_half_to_float(scaled_constant);
2584 
2585             if (fp32 != original)
2586                continue;
2587          }
2588 
2589          /* Should've been const folded */
2590          if (ins->src_abs[1] || ins->src_neg[1])
2591             continue;
2592 
2593          /* Make sure that the constant is not itself a vector
2594           * by checking if all accessed values are the same. */
2595 
2596          const midgard_constants *cons = &ins->constants;
2597          uint32_t value = is_16 ? cons->u16[component] : cons->u32[component];
2598 
2599          bool is_vector = false;
2600          unsigned mask = effective_writemask(ins->op, ins->mask);
2601 
2602          for (unsigned c = 0; c < MIR_VEC_COMPONENTS; ++c) {
2603             /* We only care if this component is actually used */
2604             if (!(mask & (1 << c)))
2605                continue;
2606 
2607             uint32_t test = is_16 ? cons->u16[ins->swizzle[1][c]]
2608                                   : cons->u32[ins->swizzle[1][c]];
2609 
2610             if (test != value) {
2611                is_vector = true;
2612                break;
2613             }
2614          }
2615 
2616          if (is_vector)
2617             continue;
2618 
2619          /* Get rid of the embedded constant */
2620          ins->has_constants = false;
2621          ins->src[1] = ~0;
2622          ins->has_inline_constant = true;
2623          ins->inline_constant = scaled_constant;
2624       }
2625    }
2626 }
2627 
2628 /* Dead code elimination for branches at the end of a block - only one branch
2629  * per block is legal semantically */
2630 
2631 static void
midgard_cull_dead_branch(compiler_context * ctx,midgard_block * block)2632 midgard_cull_dead_branch(compiler_context *ctx, midgard_block *block)
2633 {
2634    bool branched = false;
2635 
2636    mir_foreach_instr_in_block_safe(block, ins) {
2637       if (!midgard_is_branch_unit(ins->unit))
2638          continue;
2639 
2640       if (branched)
2641          mir_remove_instruction(ins);
2642 
2643       branched = true;
2644    }
2645 }
2646 
2647 /* We want to force the invert on AND/OR to the second slot to legalize into
2648  * iandnot/iornot. The relevant patterns are for AND (and OR respectively)
2649  *
2650  *   ~a & #b = ~a & ~(#~b)
2651  *   ~a & b = b & ~a
2652  */
2653 
2654 static void
midgard_legalize_invert(compiler_context * ctx,midgard_block * block)2655 midgard_legalize_invert(compiler_context *ctx, midgard_block *block)
2656 {
2657    mir_foreach_instr_in_block(block, ins) {
2658       if (ins->type != TAG_ALU_4)
2659          continue;
2660 
2661       if (ins->op != midgard_alu_op_iand && ins->op != midgard_alu_op_ior)
2662          continue;
2663 
2664       if (ins->src_invert[1] || !ins->src_invert[0])
2665          continue;
2666 
2667       if (ins->has_inline_constant) {
2668          /* ~(#~a) = ~(~#a) = a, so valid, and forces both
2669           * inverts on */
2670          ins->inline_constant = ~ins->inline_constant;
2671          ins->src_invert[1] = true;
2672       } else {
2673          /* Flip to the right invert order. Note
2674           * has_inline_constant false by assumption on the
2675           * branch, so flipping makes sense. */
2676          mir_flip(ins);
2677       }
2678    }
2679 }
2680 
2681 static unsigned
emit_fragment_epilogue(compiler_context * ctx,unsigned rt,unsigned sample_iter)2682 emit_fragment_epilogue(compiler_context *ctx, unsigned rt, unsigned sample_iter)
2683 {
2684    /* Loop to ourselves */
2685    midgard_instruction *br = ctx->writeout_branch[rt][sample_iter];
2686    struct midgard_instruction ins = v_branch(false, false);
2687    ins.writeout = br->writeout;
2688    ins.branch.target_block = ctx->block_count - 1;
2689    ins.constants.u32[0] = br->constants.u32[0];
2690    memcpy(&ins.src_types, &br->src_types, sizeof(ins.src_types));
2691    emit_mir_instruction(ctx, ins);
2692 
2693    ctx->current_block->epilogue = true;
2694    schedule_barrier(ctx);
2695    return ins.branch.target_block;
2696 }
2697 
2698 static midgard_block *
emit_block_init(compiler_context * ctx)2699 emit_block_init(compiler_context *ctx)
2700 {
2701    midgard_block *this_block = ctx->after_block;
2702    ctx->after_block = NULL;
2703 
2704    if (!this_block)
2705       this_block = create_empty_block(ctx);
2706 
2707    list_addtail(&this_block->base.link, &ctx->blocks);
2708 
2709    this_block->scheduled = false;
2710    ++ctx->block_count;
2711 
2712    /* Set up current block */
2713    list_inithead(&this_block->base.instructions);
2714    ctx->current_block = this_block;
2715 
2716    return this_block;
2717 }
2718 
2719 static midgard_block *
emit_block(compiler_context * ctx,nir_block * block)2720 emit_block(compiler_context *ctx, nir_block *block)
2721 {
2722    midgard_block *this_block = emit_block_init(ctx);
2723 
2724    nir_foreach_instr(instr, block) {
2725       emit_instr(ctx, instr);
2726       ++ctx->instruction_count;
2727    }
2728 
2729    return this_block;
2730 }
2731 
2732 static midgard_block *emit_cf_list(struct compiler_context *ctx,
2733                                    struct exec_list *list);
2734 
2735 static void
emit_if(struct compiler_context * ctx,nir_if * nif)2736 emit_if(struct compiler_context *ctx, nir_if *nif)
2737 {
2738    midgard_block *before_block = ctx->current_block;
2739 
2740    /* Speculatively emit the branch, but we can't fill it in until later */
2741    EMIT(branch, true, true);
2742    midgard_instruction *then_branch = mir_last_in_block(ctx->current_block);
2743    then_branch->src[0] = nir_src_index(ctx, &nif->condition);
2744    then_branch->src_types[0] = nir_type_uint32;
2745 
2746    /* Emit the two subblocks. */
2747    midgard_block *then_block = emit_cf_list(ctx, &nif->then_list);
2748    midgard_block *end_then_block = ctx->current_block;
2749 
2750    /* Emit a jump from the end of the then block to the end of the else */
2751    EMIT(branch, false, false);
2752    midgard_instruction *then_exit = mir_last_in_block(ctx->current_block);
2753 
2754    /* Emit second block, and check if it's empty */
2755 
2756    int else_idx = ctx->block_count;
2757    int count_in = ctx->instruction_count;
2758    midgard_block *else_block = emit_cf_list(ctx, &nif->else_list);
2759    midgard_block *end_else_block = ctx->current_block;
2760    int after_else_idx = ctx->block_count;
2761 
2762    /* Now that we have the subblocks emitted, fix up the branches */
2763 
2764    assert(then_block);
2765    assert(else_block);
2766 
2767    if (ctx->instruction_count == count_in) {
2768       /* The else block is empty, so don't emit an exit jump */
2769       mir_remove_instruction(then_exit);
2770       then_branch->branch.target_block = after_else_idx;
2771    } else {
2772       then_branch->branch.target_block = else_idx;
2773       then_exit->branch.target_block = after_else_idx;
2774    }
2775 
2776    /* Wire up the successors */
2777 
2778    ctx->after_block = create_empty_block(ctx);
2779 
2780    pan_block_add_successor(&before_block->base, &then_block->base);
2781    pan_block_add_successor(&before_block->base, &else_block->base);
2782 
2783    pan_block_add_successor(&end_then_block->base, &ctx->after_block->base);
2784    pan_block_add_successor(&end_else_block->base, &ctx->after_block->base);
2785 }
2786 
2787 static void
emit_loop(struct compiler_context * ctx,nir_loop * nloop)2788 emit_loop(struct compiler_context *ctx, nir_loop *nloop)
2789 {
2790    assert(!nir_loop_has_continue_construct(nloop));
2791 
2792    /* Remember where we are */
2793    midgard_block *start_block = ctx->current_block;
2794 
2795    /* Allocate a loop number, growing the current inner loop depth */
2796    int loop_idx = ++ctx->current_loop_depth;
2797 
2798    /* Get index from before the body so we can loop back later */
2799    int start_idx = ctx->block_count;
2800 
2801    /* Emit the body itself */
2802    midgard_block *loop_block = emit_cf_list(ctx, &nloop->body);
2803 
2804    /* Branch back to loop back */
2805    struct midgard_instruction br_back = v_branch(false, false);
2806    br_back.branch.target_block = start_idx;
2807    emit_mir_instruction(ctx, br_back);
2808 
2809    /* Mark down that branch in the graph. */
2810    pan_block_add_successor(&start_block->base, &loop_block->base);
2811    pan_block_add_successor(&ctx->current_block->base, &loop_block->base);
2812 
2813    /* Find the index of the block about to follow us (note: we don't add
2814     * one; blocks are 0-indexed so we get a fencepost problem) */
2815    int break_block_idx = ctx->block_count;
2816 
2817    /* Fix up the break statements we emitted to point to the right place,
2818     * now that we can allocate a block number for them */
2819    ctx->after_block = create_empty_block(ctx);
2820 
2821    mir_foreach_block_from(ctx, start_block, _block) {
2822       mir_foreach_instr_in_block(((midgard_block *)_block), ins) {
2823          if (ins->type != TAG_ALU_4)
2824             continue;
2825          if (!ins->compact_branch)
2826             continue;
2827 
2828          /* We found a branch -- check the type to see if we need to do anything
2829           */
2830          if (ins->branch.target_type != TARGET_BREAK)
2831             continue;
2832 
2833          /* It's a break! Check if it's our break */
2834          if (ins->branch.target_break != loop_idx)
2835             continue;
2836 
2837          /* Okay, cool, we're breaking out of this loop.
2838           * Rewrite from a break to a goto */
2839 
2840          ins->branch.target_type = TARGET_GOTO;
2841          ins->branch.target_block = break_block_idx;
2842 
2843          pan_block_add_successor(_block, &ctx->after_block->base);
2844       }
2845    }
2846 
2847    /* Now that we've finished emitting the loop, free up the depth again
2848     * so we play nice with recursion amid nested loops */
2849    --ctx->current_loop_depth;
2850 
2851    /* Dump loop stats */
2852    ++ctx->loop_count;
2853 }
2854 
2855 static midgard_block *
emit_cf_list(struct compiler_context * ctx,struct exec_list * list)2856 emit_cf_list(struct compiler_context *ctx, struct exec_list *list)
2857 {
2858    midgard_block *start_block = NULL;
2859 
2860    foreach_list_typed(nir_cf_node, node, node, list) {
2861       switch (node->type) {
2862       case nir_cf_node_block: {
2863          midgard_block *block = emit_block(ctx, nir_cf_node_as_block(node));
2864 
2865          if (!start_block)
2866             start_block = block;
2867 
2868          break;
2869       }
2870 
2871       case nir_cf_node_if:
2872          emit_if(ctx, nir_cf_node_as_if(node));
2873          break;
2874 
2875       case nir_cf_node_loop:
2876          emit_loop(ctx, nir_cf_node_as_loop(node));
2877          break;
2878 
2879       case nir_cf_node_function:
2880          assert(0);
2881          break;
2882       }
2883    }
2884 
2885    return start_block;
2886 }
2887 
2888 /* Due to lookahead, we need to report the first tag executed in the command
2889  * stream and in branch targets. An initial block might be empty, so iterate
2890  * until we find one that 'works' */
2891 
2892 unsigned
midgard_get_first_tag_from_block(compiler_context * ctx,unsigned block_idx)2893 midgard_get_first_tag_from_block(compiler_context *ctx, unsigned block_idx)
2894 {
2895    midgard_block *initial_block = mir_get_block(ctx, block_idx);
2896 
2897    mir_foreach_block_from(ctx, initial_block, _v) {
2898       midgard_block *v = (midgard_block *)_v;
2899       if (v->quadword_count) {
2900          midgard_bundle *initial_bundle =
2901             util_dynarray_element(&v->bundles, midgard_bundle, 0);
2902 
2903          return initial_bundle->tag;
2904       }
2905    }
2906 
2907    /* Default to a tag 1 which will break from the shader, in case we jump
2908     * to the exit block (i.e. `return` in a compute shader) */
2909 
2910    return 1;
2911 }
2912 
2913 /* For each fragment writeout instruction, generate a writeout loop to
2914  * associate with it */
2915 
2916 static void
mir_add_writeout_loops(compiler_context * ctx)2917 mir_add_writeout_loops(compiler_context *ctx)
2918 {
2919    for (unsigned rt = 0; rt < ARRAY_SIZE(ctx->writeout_branch); ++rt) {
2920       for (unsigned s = 0; s < MIDGARD_MAX_SAMPLE_ITER; ++s) {
2921          midgard_instruction *br = ctx->writeout_branch[rt][s];
2922          if (!br)
2923             continue;
2924 
2925          unsigned popped = br->branch.target_block;
2926          pan_block_add_successor(&(mir_get_block(ctx, popped - 1)->base),
2927                                  &ctx->current_block->base);
2928          br->branch.target_block = emit_fragment_epilogue(ctx, rt, s);
2929          br->branch.target_type = TARGET_GOTO;
2930 
2931          /* If we have more RTs, we'll need to restore back after our
2932           * loop terminates */
2933          midgard_instruction *next_br = NULL;
2934 
2935          if ((s + 1) < MIDGARD_MAX_SAMPLE_ITER)
2936             next_br = ctx->writeout_branch[rt][s + 1];
2937 
2938          if (!next_br && (rt + 1) < ARRAY_SIZE(ctx->writeout_branch))
2939             next_br = ctx->writeout_branch[rt + 1][0];
2940 
2941          if (next_br) {
2942             midgard_instruction uncond = v_branch(false, false);
2943             uncond.branch.target_block = popped;
2944             uncond.branch.target_type = TARGET_GOTO;
2945             emit_mir_instruction(ctx, uncond);
2946             pan_block_add_successor(&ctx->current_block->base,
2947                                     &(mir_get_block(ctx, popped)->base));
2948             schedule_barrier(ctx);
2949          } else {
2950             /* We're last, so we can terminate here */
2951             br->last_writeout = true;
2952          }
2953       }
2954    }
2955 }
2956 
2957 void
midgard_compile_shader_nir(nir_shader * nir,const struct panfrost_compile_inputs * inputs,struct util_dynarray * binary,struct pan_shader_info * info)2958 midgard_compile_shader_nir(nir_shader *nir,
2959                            const struct panfrost_compile_inputs *inputs,
2960                            struct util_dynarray *binary,
2961                            struct pan_shader_info *info)
2962 {
2963    midgard_debug = debug_get_option_midgard_debug();
2964 
2965    /* TODO: Bound against what? */
2966    compiler_context *ctx = rzalloc(NULL, compiler_context);
2967 
2968    ctx->inputs = inputs;
2969    ctx->nir = nir;
2970    ctx->info = info;
2971    ctx->stage = nir->info.stage;
2972    ctx->blend_input = ~0;
2973    ctx->blend_src1 = ~0;
2974    ctx->quirks = midgard_get_quirks(inputs->gpu_id);
2975 
2976    /* Initialize at a global (not block) level hash tables */
2977 
2978    ctx->ssa_constants = _mesa_hash_table_u64_create(ctx);
2979 
2980    /* Collect varyings after lowering I/O */
2981    info->quirk_no_auto32 = (ctx->quirks & MIDGARD_NO_AUTO32);
2982    pan_nir_collect_varyings(nir, info);
2983 
2984    /* Optimisation passes */
2985    optimise_nir(nir, ctx->quirks, inputs->is_blend);
2986 
2987    bool skip_internal = nir->info.internal;
2988    skip_internal &= !(midgard_debug & MIDGARD_DBG_INTERNAL);
2989 
2990    if (midgard_debug & MIDGARD_DBG_SHADERS && !skip_internal)
2991       nir_print_shader(nir, stdout);
2992 
2993    info->tls_size = nir->scratch_size;
2994 
2995    nir_foreach_function_with_impl(func, impl, nir) {
2996       list_inithead(&ctx->blocks);
2997       ctx->block_count = 0;
2998       ctx->func = func;
2999 
3000       if (nir->info.outputs_read && !inputs->is_blend) {
3001          emit_block_init(ctx);
3002 
3003          struct midgard_instruction wait = v_branch(false, false);
3004          wait.branch.target_type = TARGET_TILEBUF_WAIT;
3005 
3006          emit_mir_instruction(ctx, wait);
3007 
3008          ++ctx->instruction_count;
3009       }
3010 
3011       emit_cf_list(ctx, &impl->body);
3012       break; /* TODO: Multi-function shaders */
3013    }
3014 
3015    /* Per-block lowering before opts */
3016 
3017    mir_foreach_block(ctx, _block) {
3018       midgard_block *block = (midgard_block *)_block;
3019       inline_alu_constants(ctx, block);
3020       embedded_to_inline_constant(ctx, block);
3021    }
3022    /* MIR-level optimizations */
3023 
3024    bool progress = false;
3025 
3026    do {
3027       progress = false;
3028       progress |= midgard_opt_dead_code_eliminate(ctx);
3029       progress |= midgard_opt_prop(ctx);
3030 
3031       mir_foreach_block(ctx, _block) {
3032          midgard_block *block = (midgard_block *)_block;
3033          progress |= midgard_opt_copy_prop(ctx, block);
3034          progress |= midgard_opt_combine_projection(ctx, block);
3035          progress |= midgard_opt_varying_projection(ctx, block);
3036       }
3037    } while (progress);
3038 
3039    mir_foreach_block(ctx, _block) {
3040       midgard_block *block = (midgard_block *)_block;
3041       midgard_lower_derivatives(ctx, block);
3042       midgard_legalize_invert(ctx, block);
3043       midgard_cull_dead_branch(ctx, block);
3044    }
3045 
3046    if (ctx->stage == MESA_SHADER_FRAGMENT)
3047       mir_add_writeout_loops(ctx);
3048 
3049    /* Analyze now that the code is known but before scheduling creates
3050     * pipeline registers which are harder to track */
3051    mir_analyze_helper_requirements(ctx);
3052 
3053    if (midgard_debug & MIDGARD_DBG_SHADERS && !skip_internal)
3054       mir_print_shader(ctx);
3055 
3056    /* Schedule! */
3057    midgard_schedule_program(ctx);
3058    mir_ra(ctx);
3059 
3060    if (midgard_debug & MIDGARD_DBG_SHADERS && !skip_internal)
3061       mir_print_shader(ctx);
3062 
3063    /* Analyze after scheduling since this is order-dependent */
3064    mir_analyze_helper_terminate(ctx);
3065 
3066    /* Emit flat binary from the instruction arrays. Iterate each block in
3067     * sequence. Save instruction boundaries such that lookahead tags can
3068     * be assigned easily */
3069 
3070    /* Cache _all_ bundles in source order for lookahead across failed branches */
3071 
3072    int bundle_count = 0;
3073    mir_foreach_block(ctx, _block) {
3074       midgard_block *block = (midgard_block *)_block;
3075       bundle_count += block->bundles.size / sizeof(midgard_bundle);
3076    }
3077    midgard_bundle **source_order_bundles =
3078       malloc(sizeof(midgard_bundle *) * bundle_count);
3079    int bundle_idx = 0;
3080    mir_foreach_block(ctx, _block) {
3081       midgard_block *block = (midgard_block *)_block;
3082       util_dynarray_foreach(&block->bundles, midgard_bundle, bundle) {
3083          source_order_bundles[bundle_idx++] = bundle;
3084       }
3085    }
3086 
3087    int current_bundle = 0;
3088 
3089    /* Midgard prefetches instruction types, so during emission we
3090     * need to lookahead. Unless this is the last instruction, in
3091     * which we return 1. */
3092 
3093    mir_foreach_block(ctx, _block) {
3094       midgard_block *block = (midgard_block *)_block;
3095       mir_foreach_bundle_in_block(block, bundle) {
3096          int lookahead = 1;
3097 
3098          if (!bundle->last_writeout && (current_bundle + 1 < bundle_count))
3099             lookahead = source_order_bundles[current_bundle + 1]->tag;
3100 
3101          emit_binary_bundle(ctx, block, bundle, binary, lookahead);
3102          ++current_bundle;
3103       }
3104 
3105       /* TODO: Free deeper */
3106       // util_dynarray_fini(&block->instructions);
3107    }
3108 
3109    free(source_order_bundles);
3110 
3111    /* Report the very first tag executed */
3112    info->midgard.first_tag = midgard_get_first_tag_from_block(ctx, 0);
3113 
3114    info->ubo_mask = ctx->ubo_mask & ((1 << ctx->nir->info.num_ubos) - 1);
3115 
3116    if (midgard_debug & MIDGARD_DBG_SHADERS && !skip_internal) {
3117       disassemble_midgard(stdout, binary->data, binary->size, inputs->gpu_id,
3118                           midgard_debug & MIDGARD_DBG_VERBOSE);
3119       fflush(stdout);
3120    }
3121 
3122    /* A shader ending on a 16MB boundary causes INSTR_INVALID_PC faults,
3123     * workaround by adding some padding to the end of the shader. (The
3124     * kernel makes sure shader BOs can't cross 16MB boundaries.) */
3125    if (binary->size)
3126       memset(util_dynarray_grow(binary, uint8_t, 16), 0, 16);
3127 
3128    if ((midgard_debug & MIDGARD_DBG_SHADERDB || inputs->debug) &&
3129        !nir->info.internal) {
3130       unsigned nr_bundles = 0, nr_ins = 0;
3131 
3132       /* Count instructions and bundles */
3133 
3134       mir_foreach_block(ctx, _block) {
3135          midgard_block *block = (midgard_block *)_block;
3136          nr_bundles +=
3137             util_dynarray_num_elements(&block->bundles, midgard_bundle);
3138 
3139          mir_foreach_bundle_in_block(block, bun)
3140             nr_ins += bun->instruction_count;
3141       }
3142 
3143       /* Calculate thread count. There are certain cutoffs by
3144        * register count for thread count */
3145 
3146       unsigned nr_registers = info->work_reg_count;
3147 
3148       unsigned nr_threads = (nr_registers <= 4)   ? 4
3149                             : (nr_registers <= 8) ? 2
3150                                                   : 1;
3151 
3152       char *shaderdb = NULL;
3153 
3154       /* Dump stats */
3155 
3156       asprintf(&shaderdb,
3157                "%s shader: "
3158                "%u inst, %u bundles, %u quadwords, "
3159                "%u registers, %u threads, %u loops, "
3160                "%u:%u spills:fills",
3161                ctx->inputs->is_blend ? "PAN_SHADER_BLEND"
3162                                      : gl_shader_stage_name(ctx->stage),
3163                nr_ins, nr_bundles, ctx->quadword_count, nr_registers,
3164                nr_threads, ctx->loop_count, ctx->spills, ctx->fills);
3165 
3166       if (midgard_debug & MIDGARD_DBG_SHADERDB)
3167          fprintf(stderr, "SHADER-DB: %s\n", shaderdb);
3168 
3169       if (inputs->debug)
3170          util_debug_message(inputs->debug, SHADER_INFO, "%s", shaderdb);
3171 
3172       free(shaderdb);
3173    }
3174 
3175    _mesa_hash_table_u64_destroy(ctx->ssa_constants);
3176    ralloc_free(ctx);
3177 }
3178