1 /*
2 * Copyright 2023 Valve Corporation
3 * Copyright 2021 Alyssa Rosenzweig
4 * Copyright 2020 Collabora Ltd.
5 * Copyright 2016 Broadcom
6 * SPDX-License-Identifier: MIT
7 */
8
9 #include "compiler/nir/nir.h"
10 #include "compiler/nir/nir_builder.h"
11 #include "agx_internal_formats.h"
12 #include "agx_nir_passes.h"
13 #include "libagx_shaders.h"
14 #include "nir_builtin_builder.h"
15
16 static bool
fence_image(struct nir_builder * b,nir_intrinsic_instr * intr,void * data)17 fence_image(struct nir_builder *b, nir_intrinsic_instr *intr, void *data)
18 {
19 b->cursor = nir_after_instr(&intr->instr);
20
21 /* If the image is write-only, there is no fencing needed */
22 if (nir_intrinsic_has_access(intr) &&
23 (nir_intrinsic_access(intr) & ACCESS_NON_READABLE)) {
24 return false;
25 }
26
27 switch (intr->intrinsic) {
28 case nir_intrinsic_image_store:
29 case nir_intrinsic_bindless_image_store:
30 nir_fence_pbe_to_tex_agx(b);
31 return true;
32
33 case nir_intrinsic_image_atomic:
34 case nir_intrinsic_bindless_image_atomic:
35 case nir_intrinsic_image_atomic_swap:
36 case nir_intrinsic_bindless_image_atomic_swap:
37 nir_fence_mem_to_tex_agx(b);
38 return true;
39
40 default:
41 return false;
42 }
43 }
44
45 static nir_def *
texture_descriptor_ptr(nir_builder * b,nir_tex_instr * tex)46 texture_descriptor_ptr(nir_builder *b, nir_tex_instr *tex)
47 {
48 int handle_idx = nir_tex_instr_src_index(tex, nir_tex_src_texture_handle);
49 assert(handle_idx >= 0 && "must be bindless");
50 return nir_load_from_texture_handle_agx(b, tex->src[handle_idx].src.ssa);
51 }
52
53 static bool
has_nonzero_lod(nir_tex_instr * tex)54 has_nonzero_lod(nir_tex_instr *tex)
55 {
56 int idx = nir_tex_instr_src_index(tex, nir_tex_src_lod);
57 if (idx < 0)
58 return false;
59
60 nir_src src = tex->src[idx].src;
61 return !(nir_src_is_const(src) && nir_src_as_uint(src) == 0);
62 }
63
64 static bool
lower_tex_crawl(nir_builder * b,nir_instr * instr,UNUSED void * data)65 lower_tex_crawl(nir_builder *b, nir_instr *instr, UNUSED void *data)
66 {
67 if (instr->type != nir_instr_type_tex)
68 return false;
69
70 nir_tex_instr *tex = nir_instr_as_tex(instr);
71 b->cursor = nir_before_instr(instr);
72
73 if (tex->op != nir_texop_txs && tex->op != nir_texop_texture_samples &&
74 tex->op != nir_texop_query_levels)
75 return false;
76
77 nir_def *ptr = texture_descriptor_ptr(b, tex);
78 unsigned nr_comps = tex->def.num_components;
79 assert(nr_comps <= 3);
80
81 int lod_idx = nir_tex_instr_src_index(tex, nir_tex_src_lod);
82 nir_def *lod = lod_idx >= 0 ? nir_u2u16(b, tex->src[lod_idx].src.ssa)
83 : nir_imm_intN_t(b, 0, 16);
84
85 nir_def *res;
86 if (tex->op == nir_texop_txs) {
87 res =
88 libagx_txs(b, ptr, lod, nir_imm_int(b, nr_comps),
89 nir_imm_bool(b, tex->sampler_dim == GLSL_SAMPLER_DIM_BUF),
90 nir_imm_bool(b, tex->sampler_dim == GLSL_SAMPLER_DIM_1D),
91 nir_imm_bool(b, tex->sampler_dim == GLSL_SAMPLER_DIM_2D),
92 nir_imm_bool(b, tex->sampler_dim == GLSL_SAMPLER_DIM_CUBE),
93 nir_imm_bool(b, tex->is_array));
94 } else if (tex->op == nir_texop_query_levels) {
95 res = libagx_texture_levels(b, ptr);
96 } else {
97 res = libagx_texture_samples(b, ptr);
98 }
99
100 nir_def_rewrite_uses(&tex->def, nir_trim_vector(b, res, nr_comps));
101 nir_instr_remove(instr);
102 return true;
103 }
104
105 /*
106 * Given a 1D buffer texture coordinate, calculate the 2D coordinate vector that
107 * will be used to access the linear 2D texture bound to the buffer.
108 */
109 static nir_def *
coords_for_buffer_texture(nir_builder * b,nir_def * coord)110 coords_for_buffer_texture(nir_builder *b, nir_def *coord)
111 {
112 return nir_vec2(b, nir_iand_imm(b, coord, BITFIELD_MASK(10)),
113 nir_ushr_imm(b, coord, 10));
114 }
115
116 /*
117 * Buffer textures are lowered to 2D (1024xN) textures in the driver to access
118 * more storage. When lowering, we need to fix up the coordinate accordingly.
119 *
120 * Furthermore, RGB32 formats are emulated by lowering to global memory access,
121 * so to read a buffer texture we generate code that looks like:
122 *
123 * if (descriptor->format == RGB32)
124 * return ((uint32_t *) descriptor->address)[x];
125 * else
126 * return txf(texture_as_2d, vec2(x % 1024, x / 1024));
127 */
128 static bool
lower_buffer_texture(nir_builder * b,nir_tex_instr * tex)129 lower_buffer_texture(nir_builder *b, nir_tex_instr *tex)
130 {
131 nir_def *coord = nir_steal_tex_src(tex, nir_tex_src_coord);
132
133 /* The OpenGL ES 3.2 specification says on page 187:
134 *
135 * When a buffer texture is accessed in a shader, the results of a texel
136 * fetch are undefined if the specified texel coordinate is negative, or
137 * greater than or equal to the clamped number of texels in the texture
138 * image.
139 *
140 * However, faulting would be undesirable for robustness, so clamp.
141 */
142 nir_def *size = nir_get_texture_size(b, tex);
143 coord = nir_umin(b, coord, nir_iadd_imm(b, size, -1));
144
145 nir_def *desc = texture_descriptor_ptr(b, tex);
146 bool is_float = nir_alu_type_get_base_type(tex->dest_type) == nir_type_float;
147
148 /* Lower RGB32 reads if the format requires */
149 nir_if *nif = nir_push_if(b, libagx_texture_is_rgb32(b, desc));
150
151 nir_def *rgb32 = nir_trim_vector(
152 b, libagx_texture_load_rgb32(b, desc, coord, nir_imm_bool(b, is_float)),
153 nir_tex_instr_dest_size(tex));
154
155 nir_push_else(b, nif);
156
157 /* Otherwise, lower the texture instruction to read from 2D */
158 assert(coord->num_components == 1 && "buffer textures are 1D");
159 tex->sampler_dim = GLSL_SAMPLER_DIM_2D;
160
161 nir_def *coord2d = coords_for_buffer_texture(b, coord);
162 nir_instr_remove(&tex->instr);
163 nir_builder_instr_insert(b, &tex->instr);
164 nir_tex_instr_add_src(tex, nir_tex_src_backend1, coord2d);
165 nir_block *else_block = nir_cursor_current_block(b->cursor);
166 nir_pop_if(b, nif);
167
168 /* Put it together with a phi */
169 nir_def *phi = nir_if_phi(b, rgb32, &tex->def);
170 nir_def_rewrite_uses(&tex->def, phi);
171 nir_phi_instr *phi_instr = nir_instr_as_phi(phi->parent_instr);
172 nir_phi_src *else_src = nir_phi_get_src_from_block(phi_instr, else_block);
173 nir_src_rewrite(&else_src->src, &tex->def);
174 return true;
175 }
176
177 /*
178 * NIR indexes into array textures with unclamped floats (integer for txf). AGX
179 * requires the index to be a clamped integer. Lower tex_src_coord into
180 * tex_src_backend1 for array textures by type-converting and clamping.
181 */
182 static bool
lower_regular_texture(nir_builder * b,nir_instr * instr,UNUSED void * data)183 lower_regular_texture(nir_builder *b, nir_instr *instr, UNUSED void *data)
184 {
185 if (instr->type != nir_instr_type_tex)
186 return false;
187
188 nir_tex_instr *tex = nir_instr_as_tex(instr);
189 b->cursor = nir_before_instr(instr);
190
191 if (nir_tex_instr_is_query(tex) && tex->op != nir_texop_lod)
192 return false;
193
194 if (tex->sampler_dim == GLSL_SAMPLER_DIM_BUF)
195 return lower_buffer_texture(b, tex);
196
197 /* Don't lower twice */
198 if (nir_tex_instr_src_index(tex, nir_tex_src_backend1) >= 0)
199 return false;
200
201 /* Get the coordinates */
202 nir_def *coord = nir_steal_tex_src(tex, nir_tex_src_coord);
203 nir_def *ms_idx = nir_steal_tex_src(tex, nir_tex_src_ms_index);
204
205 /* Apply txf workaround, see libagx_lower_txf_robustness */
206 bool is_txf = ((tex->op == nir_texop_txf) || (tex->op == nir_texop_txf_ms));
207
208 if (is_txf && has_nonzero_lod(tex) &&
209 !(tex->backend_flags & AGX_TEXTURE_FLAG_NO_CLAMP)) {
210
211 int lod_idx = nir_tex_instr_src_index(tex, nir_tex_src_lod);
212
213 nir_def *replaced = libagx_lower_txf_robustness(
214 b, texture_descriptor_ptr(b, tex), tex->src[lod_idx].src.ssa,
215 nir_channel(b, coord, 0));
216
217 coord = nir_vector_insert_imm(b, coord, replaced, 0);
218 }
219
220 /* The layer is always the last component of the NIR coordinate, split it off
221 * because we'll need to swizzle.
222 */
223 nir_def *layer = NULL;
224
225 if (tex->is_array) {
226 unsigned lidx = coord->num_components - 1;
227 nir_def *unclamped_layer = nir_channel(b, coord, lidx);
228 coord = nir_trim_vector(b, coord, lidx);
229
230 /* Round layer to nearest even */
231 if (!is_txf)
232 unclamped_layer = nir_f2u32(b, nir_fround_even(b, unclamped_layer));
233
234 /* For a cube array, the layer is zero-indexed component 3 of the
235 * coordinate but the number of layers is component 2 of the txs result.
236 */
237 if (tex->sampler_dim == GLSL_SAMPLER_DIM_CUBE) {
238 assert(lidx == 3 && "4 components");
239 lidx = 2;
240 }
241
242 /* Clamp to max layer = (# of layers - 1) for out-of-bounds handling.
243 * Layer must be 16-bits for the hardware, drop top bits after clamping.
244 */
245 if (!(tex->backend_flags & AGX_TEXTURE_FLAG_NO_CLAMP)) {
246 nir_def *txs = nir_get_texture_size(b, tex);
247 nir_def *nr_layers = nir_channel(b, txs, lidx);
248 nir_def *max_layer = nir_iadd_imm(b, nr_layers, -1);
249 layer = nir_umin(b, unclamped_layer, max_layer);
250 } else {
251 layer = unclamped_layer;
252 }
253
254 layer = nir_u2u16(b, layer);
255 }
256
257 /* Combine layer and multisample index into 32-bit so we don't need a vec5 or
258 * vec6 16-bit coordinate tuple, which would be inconvenient in NIR for
259 * little benefit (a minor optimization, I guess).
260 */
261 nir_def *sample_array = (ms_idx && layer)
262 ? nir_pack_32_2x16_split(b, ms_idx, layer)
263 : ms_idx ? nir_u2u32(b, ms_idx)
264 : layer ? nir_u2u32(b, layer)
265 : NULL;
266
267 /* Combine into the final 32-bit tuple */
268 if (sample_array != NULL) {
269 unsigned end = coord->num_components;
270 coord = nir_pad_vector(b, coord, end + 1);
271 coord = nir_vector_insert_imm(b, coord, sample_array, end);
272 }
273
274 nir_tex_instr_add_src(tex, nir_tex_src_backend1, coord);
275
276 /* Furthermore, if there is an offset vector, it must be packed */
277 nir_def *offset = nir_steal_tex_src(tex, nir_tex_src_offset);
278
279 if (offset != NULL) {
280 nir_def *packed = NULL;
281
282 for (unsigned c = 0; c < offset->num_components; ++c) {
283 nir_def *nibble = nir_iand_imm(b, nir_channel(b, offset, c), 0xF);
284 nir_def *shifted = nir_ishl_imm(b, nibble, 4 * c);
285
286 if (packed != NULL)
287 packed = nir_ior(b, packed, shifted);
288 else
289 packed = shifted;
290 }
291
292 nir_tex_instr_add_src(tex, nir_tex_src_backend2, packed);
293 }
294
295 return true;
296 }
297
298 static nir_def *
bias_for_tex(nir_builder * b,nir_tex_instr * tex)299 bias_for_tex(nir_builder *b, nir_tex_instr *tex)
300 {
301 nir_instr *instr = nir_get_texture_size(b, tex)->parent_instr;
302 nir_tex_instr *query = nir_instr_as_tex(instr);
303
304 query->op = nir_texop_lod_bias_agx;
305 query->dest_type = nir_type_float16;
306
307 nir_def_init(instr, &query->def, 1, 16);
308 return &query->def;
309 }
310
311 static bool
lower_sampler_bias(nir_builder * b,nir_instr * instr,UNUSED void * data)312 lower_sampler_bias(nir_builder *b, nir_instr *instr, UNUSED void *data)
313 {
314 if (instr->type != nir_instr_type_tex)
315 return false;
316
317 nir_tex_instr *tex = nir_instr_as_tex(instr);
318 b->cursor = nir_before_instr(instr);
319
320 switch (tex->op) {
321 case nir_texop_tex: {
322 tex->op = nir_texop_txb;
323 nir_tex_instr_add_src(tex, nir_tex_src_bias, bias_for_tex(b, tex));
324 return true;
325 }
326
327 case nir_texop_txb:
328 case nir_texop_txl: {
329 nir_tex_src_type src =
330 tex->op == nir_texop_txl ? nir_tex_src_lod : nir_tex_src_bias;
331
332 nir_def *orig = nir_steal_tex_src(tex, src);
333 assert(orig != NULL && "invalid NIR");
334
335 if (orig->bit_size != 16)
336 orig = nir_f2f16(b, orig);
337
338 nir_tex_instr_add_src(tex, src, nir_fadd(b, orig, bias_for_tex(b, tex)));
339 return true;
340 }
341
342 case nir_texop_txd: {
343 /* For txd, the computed level-of-detail is log2(rho)
344 * where rho should scale proportionally to all
345 * derivatives. So scale derivatives by exp2(bias) to
346 * get level-of-detail log2(exp2(bias) * rho) = bias + log2(rho).
347 */
348 nir_def *scale = nir_fexp2(b, nir_f2f32(b, bias_for_tex(b, tex)));
349 nir_tex_src_type src[] = {nir_tex_src_ddx, nir_tex_src_ddy};
350
351 for (unsigned s = 0; s < ARRAY_SIZE(src); ++s) {
352 nir_def *orig = nir_steal_tex_src(tex, src[s]);
353 assert(orig != NULL && "invalid");
354
355 nir_def *scaled = nir_fmul(b, nir_f2f32(b, orig), scale);
356 nir_tex_instr_add_src(tex, src[s], scaled);
357 }
358
359 return true;
360 }
361
362 case nir_texop_lod: {
363 nir_tex_instr_add_src(tex, nir_tex_src_bias, bias_for_tex(b, tex));
364 return true;
365 }
366
367 case nir_texop_txf:
368 case nir_texop_txf_ms:
369 case nir_texop_txs:
370 case nir_texop_tg4:
371 case nir_texop_texture_samples:
372 case nir_texop_samples_identical:
373 case nir_texop_query_levels:
374 /* These operations do not use a sampler */
375 return false;
376
377 default:
378 unreachable("Unhandled texture operation");
379 }
380 }
381
382 static bool
legalize_image_lod(nir_builder * b,nir_intrinsic_instr * intr,UNUSED void * data)383 legalize_image_lod(nir_builder *b, nir_intrinsic_instr *intr, UNUSED void *data)
384 {
385 nir_src *src;
386
387 #define CASE(op, idx) \
388 case nir_intrinsic_##op: \
389 case nir_intrinsic_bindless_##op: \
390 src = &intr->src[idx]; \
391 break;
392
393 switch (intr->intrinsic) {
394 CASE(image_load, 3)
395 CASE(image_store, 4)
396 CASE(image_size, 1)
397 default:
398 return false;
399 }
400
401 #undef CASE
402
403 if (src->ssa->bit_size == 16)
404 return false;
405
406 b->cursor = nir_before_instr(&intr->instr);
407 nir_src_rewrite(src, nir_i2i16(b, src->ssa));
408 return true;
409 }
410
411 static nir_def *
txs_for_image(nir_builder * b,nir_intrinsic_instr * intr,unsigned num_components,unsigned bit_size,bool query_samples)412 txs_for_image(nir_builder *b, nir_intrinsic_instr *intr,
413 unsigned num_components, unsigned bit_size, bool query_samples)
414 {
415 nir_tex_instr *tex = nir_tex_instr_create(b->shader, query_samples ? 1 : 2);
416 tex->op = query_samples ? nir_texop_texture_samples : nir_texop_txs;
417 tex->is_array = nir_intrinsic_image_array(intr);
418 tex->dest_type = nir_type_uint32;
419 tex->sampler_dim = nir_intrinsic_image_dim(intr);
420
421 tex->src[0] =
422 nir_tex_src_for_ssa(nir_tex_src_texture_handle, intr->src[0].ssa);
423
424 if (!query_samples)
425 tex->src[1] = nir_tex_src_for_ssa(nir_tex_src_lod, intr->src[1].ssa);
426
427 nir_def_init(&tex->instr, &tex->def, num_components, bit_size);
428 nir_builder_instr_insert(b, &tex->instr);
429 nir_def *res = &tex->def;
430
431 /* Cube images are implemented as 2D arrays, so we need to divide here. */
432 if (tex->sampler_dim == GLSL_SAMPLER_DIM_CUBE && res->num_components > 2 &&
433 !query_samples) {
434 nir_def *divided = nir_udiv_imm(b, nir_channel(b, res, 2), 6);
435 res = nir_vector_insert_imm(b, res, divided, 2);
436 }
437
438 return res;
439 }
440
441 static nir_def *
image_texel_address(nir_builder * b,nir_intrinsic_instr * intr,bool return_index)442 image_texel_address(nir_builder *b, nir_intrinsic_instr *intr,
443 bool return_index)
444 {
445 /* First, calculate the address of the PBE descriptor */
446 nir_def *desc_address =
447 nir_load_from_texture_handle_agx(b, intr->src[0].ssa);
448
449 nir_def *coord = intr->src[1].ssa;
450 enum pipe_format format = nir_intrinsic_format(intr);
451 nir_def *blocksize_B = nir_imm_int(b, util_format_get_blocksize(format));
452
453 enum glsl_sampler_dim dim = nir_intrinsic_image_dim(intr);
454 bool layered = nir_intrinsic_image_array(intr) ||
455 (dim == GLSL_SAMPLER_DIM_CUBE) ||
456 (dim == GLSL_SAMPLER_DIM_3D);
457
458 /* The last 8 bytes of the 24-byte PBE descriptor points to the
459 * software-defined atomic descriptor. Grab the address.
460 */
461 nir_def *meta_meta_ptr = nir_iadd_imm(b, desc_address, 16);
462 nir_def *meta_ptr = nir_load_global_constant(b, meta_meta_ptr, 8, 1, 64);
463
464 if (dim == GLSL_SAMPLER_DIM_BUF && return_index) {
465 return nir_channel(b, coord, 0);
466 } else if (dim == GLSL_SAMPLER_DIM_BUF) {
467 return libagx_buffer_texel_address(b, meta_ptr, coord, blocksize_B);
468 } else {
469 return libagx_image_texel_address(
470 b, meta_ptr, coord, nir_u2u32(b, intr->src[2].ssa), blocksize_B,
471 nir_imm_bool(b, dim == GLSL_SAMPLER_DIM_MS), nir_imm_bool(b, layered),
472 nir_imm_bool(b, return_index));
473 }
474 }
475
476 static void
lower_buffer_image(nir_builder * b,nir_intrinsic_instr * intr)477 lower_buffer_image(nir_builder *b, nir_intrinsic_instr *intr)
478 {
479 nir_def *coord_vector = intr->src[1].ssa;
480 nir_def *coord = nir_channel(b, coord_vector, 0);
481
482 /* Lower the buffer load/store to a 2D image load/store, matching the 2D
483 * texture/PBE descriptor the driver supplies for buffer images.
484 */
485 nir_def *coord2d = coords_for_buffer_texture(b, coord);
486 nir_src_rewrite(&intr->src[1], nir_pad_vector(b, coord2d, 4));
487 nir_intrinsic_set_image_dim(intr, GLSL_SAMPLER_DIM_2D);
488 }
489
490 static void
lower_1d_image(nir_builder * b,nir_intrinsic_instr * intr)491 lower_1d_image(nir_builder *b, nir_intrinsic_instr *intr)
492 {
493 nir_def *coord = intr->src[1].ssa;
494 bool is_array = nir_intrinsic_image_array(intr);
495 nir_def *zero = nir_imm_intN_t(b, 0, coord->bit_size);
496
497 if (is_array) {
498 assert(coord->num_components >= 2);
499 coord =
500 nir_vec3(b, nir_channel(b, coord, 0), zero, nir_channel(b, coord, 1));
501 } else {
502 assert(coord->num_components >= 1);
503 coord = nir_vec2(b, coord, zero);
504 }
505
506 nir_src_rewrite(&intr->src[1], nir_pad_vector(b, coord, 4));
507 nir_intrinsic_set_image_dim(intr, GLSL_SAMPLER_DIM_2D);
508 }
509
510 static bool
lower_images(nir_builder * b,nir_intrinsic_instr * intr,UNUSED void * data)511 lower_images(nir_builder *b, nir_intrinsic_instr *intr, UNUSED void *data)
512 {
513 b->cursor = nir_before_instr(&intr->instr);
514
515 switch (intr->intrinsic) {
516 case nir_intrinsic_image_load:
517 case nir_intrinsic_image_store:
518 case nir_intrinsic_bindless_image_load:
519 case nir_intrinsic_bindless_image_store: {
520 /* Legalize MSAA index */
521 nir_src_rewrite(&intr->src[2], nir_u2u16(b, intr->src[2].ssa));
522
523 switch (nir_intrinsic_image_dim(intr)) {
524 case GLSL_SAMPLER_DIM_1D:
525 lower_1d_image(b, intr);
526 return true;
527
528 case GLSL_SAMPLER_DIM_BUF:
529 lower_buffer_image(b, intr);
530 return true;
531
532 default:
533 return true;
534 }
535 }
536
537 case nir_intrinsic_bindless_image_size:
538 case nir_intrinsic_bindless_image_samples:
539 nir_def_rewrite_uses(
540 &intr->def,
541 txs_for_image(
542 b, intr, intr->def.num_components, intr->def.bit_size,
543 intr->intrinsic == nir_intrinsic_bindless_image_samples));
544 return true;
545
546 case nir_intrinsic_bindless_image_texel_address:
547 nir_def_rewrite_uses(&intr->def, image_texel_address(b, intr, false));
548 return true;
549
550 case nir_intrinsic_image_size:
551 case nir_intrinsic_image_texel_address:
552 unreachable("should've been lowered");
553
554 default:
555 return false;
556 }
557 }
558
559 /*
560 * Early texture lowering passes, called by the driver before lowering
561 * descriptor bindings. That means these passes operate on texture derefs. The
562 * purpose is to make descriptor crawls explicit in the NIR, so that the driver
563 * can accurately lower descriptors after this pass but before calling
564 * the full agx_nir_lower_texture.
565 */
566 bool
agx_nir_lower_texture_early(nir_shader * s,bool support_lod_bias)567 agx_nir_lower_texture_early(nir_shader *s, bool support_lod_bias)
568 {
569 bool progress = false;
570
571 nir_lower_tex_options lower_tex_options = {
572 .lower_txp = ~0,
573 .lower_invalid_implicit_lod = true,
574 .lower_tg4_offsets = true,
575 .lower_index_to_offset = true,
576
577 /* Unclear if/how mipmapped 1D textures work in the hardware. */
578 .lower_1d = true,
579
580 /* XXX: Metal seems to handle just like 3D txd, so why doesn't it work?
581 * TODO: Stop using this lowering
582 */
583 .lower_txd_cube_map = true,
584 };
585
586 NIR_PASS(progress, s, nir_lower_tex, &lower_tex_options);
587
588 /* Lower bias after nir_lower_tex (to get rid of txd) but before
589 * lower_regular_texture (which will shuffle around the sources)
590 */
591 if (support_lod_bias) {
592 NIR_PASS(progress, s, nir_shader_instructions_pass, lower_sampler_bias,
593 nir_metadata_block_index | nir_metadata_dominance, NULL);
594 }
595
596 return progress;
597 }
598
599 bool
agx_nir_lower_texture(nir_shader * s)600 agx_nir_lower_texture(nir_shader *s)
601 {
602 bool progress = false;
603
604 nir_tex_src_type_constraints tex_constraints = {
605 [nir_tex_src_lod] = {true, 16},
606 [nir_tex_src_bias] = {true, 16},
607 [nir_tex_src_ms_index] = {true, 16},
608 [nir_tex_src_texture_offset] = {true, 16},
609 [nir_tex_src_sampler_offset] = {true, 16},
610 };
611
612 /* Insert fences before lowering image atomics, since image atomics need
613 * different fencing than other image operations.
614 */
615 NIR_PASS(progress, s, nir_shader_intrinsics_pass, fence_image,
616 nir_metadata_block_index | nir_metadata_dominance, NULL);
617
618 NIR_PASS(progress, s, nir_lower_image_atomics_to_global);
619
620 NIR_PASS(progress, s, nir_shader_intrinsics_pass, legalize_image_lod,
621 nir_metadata_block_index | nir_metadata_dominance, NULL);
622 NIR_PASS(progress, s, nir_shader_intrinsics_pass, lower_images,
623 nir_metadata_block_index | nir_metadata_dominance, NULL);
624 NIR_PASS(progress, s, nir_legalize_16bit_sampler_srcs, tex_constraints);
625
626 /* Fold constants after nir_legalize_16bit_sampler_srcs so we can detect 0 in
627 * lower_regular_texture. This is required for correctness.
628 */
629 NIR_PASS(progress, s, nir_opt_constant_folding);
630
631 /* Lower texture sources after legalizing types (as the lowering depends on
632 * 16-bit multisample indices) but before lowering queries (as the lowering
633 * generates txs for array textures).
634 */
635 NIR_PASS(progress, s, nir_shader_instructions_pass, lower_regular_texture,
636 nir_metadata_none, NULL);
637 NIR_PASS(progress, s, nir_shader_instructions_pass, lower_tex_crawl,
638 nir_metadata_block_index | nir_metadata_dominance, NULL);
639
640 return progress;
641 }
642
643 static bool
lower_multisampled_store(nir_builder * b,nir_intrinsic_instr * intr,UNUSED void * data)644 lower_multisampled_store(nir_builder *b, nir_intrinsic_instr *intr,
645 UNUSED void *data)
646 {
647 b->cursor = nir_before_instr(&intr->instr);
648
649 if (intr->intrinsic != nir_intrinsic_bindless_image_store)
650 return false;
651
652 if (nir_intrinsic_image_dim(intr) != GLSL_SAMPLER_DIM_MS)
653 return false;
654
655 nir_def *index_px = nir_u2u32(b, image_texel_address(b, intr, true));
656 nir_def *coord2d = coords_for_buffer_texture(b, index_px);
657
658 nir_src_rewrite(&intr->src[1], nir_pad_vector(b, coord2d, 4));
659 nir_src_rewrite(&intr->src[2], nir_imm_int(b, 0));
660 nir_intrinsic_set_image_dim(intr, GLSL_SAMPLER_DIM_2D);
661 nir_intrinsic_set_image_array(intr, false);
662 return true;
663 }
664
665 bool
agx_nir_lower_multisampled_image_store(nir_shader * s)666 agx_nir_lower_multisampled_image_store(nir_shader *s)
667 {
668 return nir_shader_intrinsics_pass(
669 s, lower_multisampled_store,
670 nir_metadata_block_index | nir_metadata_dominance, NULL);
671 }
672
673 /*
674 * Given a non-bindless instruction, return whether agx_nir_lower_texture will
675 * lower it to something involving a descriptor crawl. This requires the driver
676 * to lower the instruction to bindless before calling agx_nir_lower_texture.
677 * The implementation just enumerates the cases handled in this file.
678 */
679 bool
agx_nir_needs_texture_crawl(nir_instr * instr)680 agx_nir_needs_texture_crawl(nir_instr *instr)
681 {
682 if (instr->type == nir_instr_type_intrinsic) {
683 nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
684
685 switch (intr->intrinsic) {
686 /* Queries, atomics always become a crawl */
687 case nir_intrinsic_image_size:
688 case nir_intrinsic_image_deref_size:
689 case nir_intrinsic_image_samples:
690 case nir_intrinsic_image_deref_samples:
691 case nir_intrinsic_image_atomic:
692 case nir_intrinsic_image_deref_atomic:
693 case nir_intrinsic_image_atomic_swap:
694 case nir_intrinsic_image_deref_atomic_swap:
695 return true;
696
697 /* Multisampled stores need a crawl, others do not */
698 case nir_intrinsic_image_store:
699 case nir_intrinsic_image_deref_store:
700 return nir_intrinsic_image_dim(intr) == GLSL_SAMPLER_DIM_MS;
701
702 /* Loads do not need a crawl, even from buffers */
703 default:
704 return false;
705 }
706 } else if (instr->type == nir_instr_type_tex) {
707 nir_tex_instr *tex = nir_instr_as_tex(instr);
708
709 /* Array textures get clamped to their size via txs */
710 if (tex->is_array && !(tex->backend_flags & AGX_TEXTURE_FLAG_NO_CLAMP))
711 return true;
712
713 switch (tex->op) {
714 /* Queries always become a crawl */
715 case nir_texop_txs:
716 case nir_texop_texture_samples:
717 case nir_texop_query_levels:
718 return true;
719
720 /* Buffer textures need their format read and txf needs its LOD clamped.
721 * Buffer textures are only read through txf.
722 */
723 case nir_texop_txf:
724 case nir_texop_txf_ms:
725 return has_nonzero_lod(tex) ||
726 tex->sampler_dim == GLSL_SAMPLER_DIM_BUF;
727
728 default:
729 return false;
730 }
731 }
732
733 return false;
734 }
735