1 /*
2 * Copyright © 2015 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24 #include "brw_context.h"
25 #include "compiler/brw_nir.h"
26 #include "brw_program.h"
27 #include "compiler/glsl/ir.h"
28 #include "compiler/glsl/ir_optimization.h"
29 #include "compiler/glsl/program.h"
30 #include "compiler/nir/nir_serialize.h"
31 #include "program/program.h"
32 #include "main/mtypes.h"
33 #include "main/shaderapi.h"
34 #include "main/shaderobj.h"
35 #include "main/uniforms.h"
36
37 /**
38 * Performs a compile of the shader stages even when we don't know
39 * what non-orthogonal state will be set, in the hope that it reflects
40 * the eventual NOS used, and thus allows us to produce link failures.
41 */
42 static bool
brw_shader_precompile(struct gl_context * ctx,struct gl_shader_program * sh_prog)43 brw_shader_precompile(struct gl_context *ctx,
44 struct gl_shader_program *sh_prog)
45 {
46 struct gl_linked_shader *vs = sh_prog->_LinkedShaders[MESA_SHADER_VERTEX];
47 struct gl_linked_shader *tcs = sh_prog->_LinkedShaders[MESA_SHADER_TESS_CTRL];
48 struct gl_linked_shader *tes = sh_prog->_LinkedShaders[MESA_SHADER_TESS_EVAL];
49 struct gl_linked_shader *gs = sh_prog->_LinkedShaders[MESA_SHADER_GEOMETRY];
50 struct gl_linked_shader *fs = sh_prog->_LinkedShaders[MESA_SHADER_FRAGMENT];
51 struct gl_linked_shader *cs = sh_prog->_LinkedShaders[MESA_SHADER_COMPUTE];
52
53 if (fs && !brw_fs_precompile(ctx, fs->Program))
54 return false;
55
56 if (gs && !brw_gs_precompile(ctx, gs->Program))
57 return false;
58
59 if (tes && !brw_tes_precompile(ctx, sh_prog, tes->Program))
60 return false;
61
62 if (tcs && !brw_tcs_precompile(ctx, sh_prog, tcs->Program))
63 return false;
64
65 if (vs && !brw_vs_precompile(ctx, vs->Program))
66 return false;
67
68 if (cs && !brw_cs_precompile(ctx, cs->Program))
69 return false;
70
71 return true;
72 }
73
74 static void
brw_lower_packing_builtins(struct brw_context * brw,exec_list * ir)75 brw_lower_packing_builtins(struct brw_context *brw,
76 exec_list *ir)
77 {
78 const struct gen_device_info *devinfo = &brw->screen->devinfo;
79
80 /* Gens < 7 don't have instructions to convert to or from half-precision,
81 * and Gens < 6 don't expose that functionality.
82 */
83 if (devinfo->gen != 6)
84 return;
85
86 lower_packing_builtins(ir, LOWER_PACK_HALF_2x16 | LOWER_UNPACK_HALF_2x16);
87 }
88
89 static void
process_glsl_ir(struct brw_context * brw,struct gl_shader_program * shader_prog,struct gl_linked_shader * shader)90 process_glsl_ir(struct brw_context *brw,
91 struct gl_shader_program *shader_prog,
92 struct gl_linked_shader *shader)
93 {
94 const struct gen_device_info *devinfo = &brw->screen->devinfo;
95 struct gl_context *ctx = &brw->ctx;
96
97 /* Temporary memory context for any new IR. */
98 void *mem_ctx = ralloc_context(NULL);
99
100 ralloc_adopt(mem_ctx, shader->ir);
101
102 lower_blend_equation_advanced(shader);
103
104 /* lower_packing_builtins() inserts arithmetic instructions, so it
105 * must precede lower_instructions().
106 */
107 brw_lower_packing_builtins(brw, shader->ir);
108 do_mat_op_to_vec(shader->ir);
109
110 unsigned instructions_to_lower = (DIV_TO_MUL_RCP |
111 SUB_TO_ADD_NEG |
112 EXP_TO_EXP2 |
113 LOG_TO_LOG2 |
114 DFREXP_DLDEXP_TO_ARITH);
115 if (devinfo->gen < 7) {
116 instructions_to_lower |= BIT_COUNT_TO_MATH |
117 EXTRACT_TO_SHIFTS |
118 INSERT_TO_SHIFTS |
119 REVERSE_TO_SHIFTS;
120 }
121
122 lower_instructions(shader->ir, instructions_to_lower);
123
124 /* Pre-gen6 HW can only nest if-statements 16 deep. Beyond this,
125 * if-statements need to be flattened.
126 */
127 if (devinfo->gen < 6)
128 lower_if_to_cond_assign(shader->Stage, shader->ir, 16);
129
130 do_lower_texture_projection(shader->ir);
131 do_vec_index_to_cond_assign(shader->ir);
132 lower_vector_insert(shader->ir, true);
133 lower_offset_arrays(shader->ir);
134 lower_noise(shader->ir);
135 lower_quadop_vector(shader->ir, false);
136
137 validate_ir_tree(shader->ir);
138
139 /* Now that we've finished altering the linked IR, reparent any live IR back
140 * to the permanent memory context, and free the temporary one (discarding any
141 * junk we optimized away).
142 */
143 reparent_ir(shader->ir, shader->ir);
144 ralloc_free(mem_ctx);
145
146 if (ctx->_Shader->Flags & GLSL_DUMP) {
147 fprintf(stderr, "\n");
148 if (shader->ir) {
149 fprintf(stderr, "GLSL IR for linked %s program %d:\n",
150 _mesa_shader_stage_to_string(shader->Stage),
151 shader_prog->Name);
152 _mesa_print_ir(stderr, shader->ir, NULL);
153 } else {
154 fprintf(stderr, "No GLSL IR for linked %s program %d (shader may be "
155 "from cache)\n", _mesa_shader_stage_to_string(shader->Stage),
156 shader_prog->Name);
157 }
158 fprintf(stderr, "\n");
159 }
160 }
161
162 static void
unify_interfaces(struct shader_info ** infos)163 unify_interfaces(struct shader_info **infos)
164 {
165 struct shader_info *prev_info = NULL;
166
167 for (unsigned i = MESA_SHADER_VERTEX; i < MESA_SHADER_FRAGMENT; i++) {
168 if (!infos[i])
169 continue;
170
171 if (prev_info) {
172 prev_info->outputs_written |= infos[i]->inputs_read &
173 ~(VARYING_BIT_TESS_LEVEL_INNER | VARYING_BIT_TESS_LEVEL_OUTER);
174 infos[i]->inputs_read |= prev_info->outputs_written &
175 ~(VARYING_BIT_TESS_LEVEL_INNER | VARYING_BIT_TESS_LEVEL_OUTER);
176
177 prev_info->patch_outputs_written |= infos[i]->patch_inputs_read;
178 infos[i]->patch_inputs_read |= prev_info->patch_outputs_written;
179 }
180 prev_info = infos[i];
181 }
182 }
183
184 static void
update_xfb_info(struct gl_transform_feedback_info * xfb_info,struct shader_info * info)185 update_xfb_info(struct gl_transform_feedback_info *xfb_info,
186 struct shader_info *info)
187 {
188 if (!xfb_info)
189 return;
190
191 for (unsigned i = 0; i < xfb_info->NumOutputs; i++) {
192 struct gl_transform_feedback_output *output = &xfb_info->Outputs[i];
193
194 /* The VUE header contains three scalar fields packed together:
195 * - gl_PointSize is stored in VARYING_SLOT_PSIZ.w
196 * - gl_Layer is stored in VARYING_SLOT_PSIZ.y
197 * - gl_ViewportIndex is stored in VARYING_SLOT_PSIZ.z
198 */
199 switch (output->OutputRegister) {
200 case VARYING_SLOT_LAYER:
201 assert(output->NumComponents == 1);
202 output->OutputRegister = VARYING_SLOT_PSIZ;
203 output->ComponentOffset = 1;
204 break;
205 case VARYING_SLOT_VIEWPORT:
206 assert(output->NumComponents == 1);
207 output->OutputRegister = VARYING_SLOT_PSIZ;
208 output->ComponentOffset = 2;
209 break;
210 case VARYING_SLOT_PSIZ:
211 assert(output->NumComponents == 1);
212 output->ComponentOffset = 3;
213 break;
214 }
215
216 info->outputs_written |= 1ull << output->OutputRegister;
217 }
218 }
219
220 extern "C" GLboolean
brw_link_shader(struct gl_context * ctx,struct gl_shader_program * shProg)221 brw_link_shader(struct gl_context *ctx, struct gl_shader_program *shProg)
222 {
223 struct brw_context *brw = brw_context(ctx);
224 const struct brw_compiler *compiler = brw->screen->compiler;
225 unsigned int stage;
226 struct shader_info *infos[MESA_SHADER_STAGES] = { 0, };
227
228 if (shProg->data->LinkStatus == linking_skipped)
229 return GL_TRUE;
230
231 for (stage = 0; stage < ARRAY_SIZE(shProg->_LinkedShaders); stage++) {
232 struct gl_linked_shader *shader = shProg->_LinkedShaders[stage];
233 if (!shader)
234 continue;
235
236 struct gl_program *prog = shader->Program;
237 prog->Parameters = _mesa_new_parameter_list();
238
239 process_glsl_ir(brw, shProg, shader);
240
241 _mesa_copy_linked_program_data(shProg, shader);
242
243 prog->ShadowSamplers = shader->shadow_samplers;
244 _mesa_update_shader_textures_used(shProg, prog);
245
246 bool debug_enabled =
247 (INTEL_DEBUG & intel_debug_flag_for_shader_stage(shader->Stage));
248
249 if (debug_enabled && shader->ir) {
250 fprintf(stderr, "GLSL IR for native %s shader %d:\n",
251 _mesa_shader_stage_to_string(shader->Stage), shProg->Name);
252 _mesa_print_ir(stderr, shader->ir, NULL);
253 fprintf(stderr, "\n\n");
254 }
255
256 prog->nir = brw_create_nir(brw, shProg, prog, (gl_shader_stage) stage,
257 compiler->scalar_stage[stage]);
258 }
259
260 /* Determine first and last stage. */
261 unsigned first = MESA_SHADER_STAGES;
262 unsigned last = 0;
263 for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) {
264 if (!shProg->_LinkedShaders[i])
265 continue;
266 if (first == MESA_SHADER_STAGES)
267 first = i;
268 last = i;
269 }
270
271 /* Linking the stages in the opposite order (from fragment to vertex)
272 * ensures that inter-shader outputs written to in an earlier stage
273 * are eliminated if they are (transitively) not used in a later
274 * stage.
275 *
276 * TODO: Look into Shadow of Mordor regressions on HSW and enable this for
277 * all platforms. See: https://bugs.freedesktop.org/show_bug.cgi?id=103537
278 */
279 if (first != last && brw->screen->devinfo.gen >= 8) {
280 int next = last;
281 for (int i = next - 1; i >= 0; i--) {
282 if (shProg->_LinkedShaders[i] == NULL)
283 continue;
284
285 brw_nir_link_shaders(compiler,
286 &shProg->_LinkedShaders[i]->Program->nir,
287 &shProg->_LinkedShaders[next]->Program->nir);
288 next = i;
289 }
290 }
291
292 for (stage = 0; stage < ARRAY_SIZE(shProg->_LinkedShaders); stage++) {
293 struct gl_linked_shader *shader = shProg->_LinkedShaders[stage];
294 if (!shader)
295 continue;
296
297 struct gl_program *prog = shader->Program;
298 brw_shader_gather_info(prog->nir, prog);
299
300 NIR_PASS_V(prog->nir, nir_lower_samplers, shProg);
301 NIR_PASS_V(prog->nir, nir_lower_atomics, shProg);
302 NIR_PASS_V(prog->nir, nir_lower_atomics_to_ssbo,
303 prog->nir->info.num_abos);
304
305 infos[stage] = &prog->nir->info;
306
307 update_xfb_info(prog->sh.LinkedTransformFeedback, infos[stage]);
308
309 /* Make a pass over the IR to add state references for any built-in
310 * uniforms that are used. This has to be done now (during linking).
311 * Code generation doesn't happen until the first time this shader is
312 * used for rendering. Waiting until then to generate the parameters is
313 * too late. At that point, the values for the built-in uniforms won't
314 * get sent to the shader.
315 */
316 nir_foreach_variable(var, &prog->nir->uniforms) {
317 if (strncmp(var->name, "gl_", 3) == 0) {
318 const nir_state_slot *const slots = var->state_slots;
319 assert(var->state_slots != NULL);
320
321 for (unsigned int i = 0; i < var->num_state_slots; i++) {
322 _mesa_add_state_reference(prog->Parameters,
323 (gl_state_index *)slots[i].tokens);
324 }
325 }
326 }
327 }
328
329 /* The linker tries to dead code eliminate unused varying components,
330 * and make sure interfaces match. But it isn't able to do so in all
331 * cases. So, explicitly make the interfaces match by OR'ing together
332 * the inputs_read/outputs_written bitfields of adjacent stages.
333 */
334 if (!shProg->SeparateShader)
335 unify_interfaces(infos);
336
337 if ((ctx->_Shader->Flags & GLSL_DUMP) && shProg->Name != 0) {
338 for (unsigned i = 0; i < shProg->NumShaders; i++) {
339 const struct gl_shader *sh = shProg->Shaders[i];
340 if (!sh)
341 continue;
342
343 fprintf(stderr, "GLSL %s shader %d source for linked program %d:\n",
344 _mesa_shader_stage_to_string(sh->Stage),
345 i, shProg->Name);
346 fprintf(stderr, "%s", sh->Source);
347 fprintf(stderr, "\n");
348 }
349 }
350
351 if (brw->ctx.Cache) {
352 for (stage = 0; stage < ARRAY_SIZE(shProg->_LinkedShaders); stage++) {
353 struct gl_linked_shader *shader = shProg->_LinkedShaders[stage];
354 if (!shader)
355 continue;
356
357 struct gl_program *prog = shader->Program;
358 brw_program_serialize_nir(ctx, prog);
359 }
360 }
361
362 if (brw->precompile && !brw_shader_precompile(ctx, shProg))
363 return false;
364
365 build_program_resource_list(ctx, shProg);
366
367 for (stage = 0; stage < ARRAY_SIZE(shProg->_LinkedShaders); stage++) {
368 struct gl_linked_shader *shader = shProg->_LinkedShaders[stage];
369 if (!shader)
370 continue;
371
372 /* The GLSL IR won't be needed anymore. */
373 ralloc_free(shader->ir);
374 shader->ir = NULL;
375 }
376
377 return true;
378 }
379