brw_nir.c revision faf5f174ddbc7680f6947ceababb94fdb552bcdb 
1/*
2 * Copyright © 2014 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_nir.h"
25#include "brw_shader.h"
26#include "glsl/glsl_parser_extras.h"
27#include "glsl/nir/glsl_to_nir.h"
28#include "program/prog_to_nir.h"
29
30static void
31nir_optimize(nir_shader *nir, bool is_scalar)
32{
33   bool progress;
34   do {
35      progress = false;
36      nir_lower_vars_to_ssa(nir);
37      nir_validate_shader(nir);
38
39      if (is_scalar) {
40         nir_lower_alu_to_scalar(nir);
41         nir_validate_shader(nir);
42      }
43
44      progress |= nir_copy_prop(nir);
45      nir_validate_shader(nir);
46
47      if (is_scalar) {
48         nir_lower_phis_to_scalar(nir);
49         nir_validate_shader(nir);
50      }
51
52      progress |= nir_copy_prop(nir);
53      nir_validate_shader(nir);
54      progress |= nir_opt_dce(nir);
55      nir_validate_shader(nir);
56      progress |= nir_opt_cse(nir);
57      nir_validate_shader(nir);
58      progress |= nir_opt_peephole_select(nir);
59      nir_validate_shader(nir);
60      progress |= nir_opt_algebraic(nir);
61      nir_validate_shader(nir);
62      progress |= nir_opt_constant_folding(nir);
63      nir_validate_shader(nir);
64      progress |= nir_opt_dead_cf(nir);
65      nir_validate_shader(nir);
66      progress |= nir_opt_remove_phis(nir);
67      nir_validate_shader(nir);
68      progress |= nir_opt_undef(nir);
69      nir_validate_shader(nir);
70   } while (progress);
71}
72
73nir_shader *
74brw_create_nir(struct brw_context *brw,
75               const struct gl_shader_program *shader_prog,
76               const struct gl_program *prog,
77               gl_shader_stage stage,
78               bool is_scalar)
79{
80   struct gl_context *ctx = &brw->ctx;
81   const nir_shader_compiler_options *options =
82      ctx->Const.ShaderCompilerOptions[stage].NirOptions;
83   static const nir_lower_tex_options tex_options = {
84      .lower_txp = ~0,
85   };
86   struct gl_shader *shader = shader_prog ? shader_prog->_LinkedShaders[stage] : NULL;
87   bool debug_enabled = INTEL_DEBUG & intel_debug_flag_for_shader_stage(stage);
88   nir_shader *nir;
89
90   /* First, lower the GLSL IR or Mesa IR to NIR */
91   if (shader_prog) {
92      nir = glsl_to_nir(shader, options);
93   } else {
94      nir = prog_to_nir(prog, options);
95      nir_convert_to_ssa(nir); /* turn registers into SSA */
96   }
97   nir_validate_shader(nir);
98
99   nir_lower_global_vars_to_local(nir);
100   nir_validate_shader(nir);
101
102   nir_lower_tex(nir, &tex_options);
103   nir_validate_shader(nir);
104
105   nir_normalize_cubemap_coords(nir);
106   nir_validate_shader(nir);
107
108   nir_split_var_copies(nir);
109   nir_validate_shader(nir);
110
111   nir_optimize(nir, is_scalar);
112
113   /* Lower a bunch of stuff */
114   nir_lower_var_copies(nir);
115   nir_validate_shader(nir);
116
117   /* Get rid of split copies */
118   nir_optimize(nir, is_scalar);
119
120   if (is_scalar) {
121      nir_assign_var_locations(&nir->uniforms,
122                               &nir->num_uniforms,
123                               type_size_scalar);
124      nir_assign_var_locations(&nir->inputs, &nir->num_inputs, type_size_scalar);
125      nir_assign_var_locations(&nir->outputs, &nir->num_outputs, type_size_scalar);
126      nir_lower_io(nir, type_size_scalar);
127   } else {
128      nir_assign_var_locations(&nir->uniforms,
129                               &nir->num_uniforms,
130                               type_size_vec4);
131
132      nir_assign_var_locations(&nir->inputs, &nir->num_inputs, type_size_vec4);
133
134      foreach_list_typed(nir_variable, var, node, &nir->outputs)
135         var->data.driver_location = var->data.location;
136
137      nir_lower_io(nir, type_size_vec4);
138   }
139
140   nir_validate_shader(nir);
141
142   nir_remove_dead_variables(nir);
143   nir_validate_shader(nir);
144
145   if (shader_prog) {
146      nir_lower_samplers(nir, shader_prog);
147      nir_validate_shader(nir);
148   }
149
150   nir_lower_system_values(nir);
151   nir_validate_shader(nir);
152
153   nir_lower_atomics(nir);
154   nir_validate_shader(nir);
155
156   nir_optimize(nir, is_scalar);
157
158   if (brw->gen >= 6) {
159      /* Try and fuse multiply-adds */
160      nir_opt_peephole_ffma(nir);
161      nir_validate_shader(nir);
162   }
163
164   nir_opt_algebraic_late(nir);
165   nir_validate_shader(nir);
166
167   nir_lower_locals_to_regs(nir);
168   nir_validate_shader(nir);
169
170   nir_lower_to_source_mods(nir);
171   nir_validate_shader(nir);
172   nir_copy_prop(nir);
173   nir_validate_shader(nir);
174   nir_opt_dce(nir);
175   nir_validate_shader(nir);
176
177   if (unlikely(debug_enabled)) {
178      /* Re-index SSA defs so we print more sensible numbers. */
179      nir_foreach_overload(nir, overload) {
180         if (overload->impl)
181            nir_index_ssa_defs(overload->impl);
182      }
183
184      fprintf(stderr, "NIR (SSA form) for %s shader:\n",
185              _mesa_shader_stage_to_string(stage));
186      nir_print_shader(nir, stderr);
187   }
188
189   nir_convert_from_ssa(nir, true);
190   nir_validate_shader(nir);
191
192   if (!is_scalar) {
193      nir_move_vec_src_uses_to_dest(nir);
194      nir_validate_shader(nir);
195
196      nir_lower_vec_to_movs(nir);
197      nir_validate_shader(nir);
198   }
199
200   /* This is the last pass we run before we start emitting stuff.  It
201    * determines when we need to insert boolean resolves on Gen <= 5.  We
202    * run it last because it stashes data in instr->pass_flags and we don't
203    * want that to be squashed by other NIR passes.
204    */
205   if (brw->gen <= 5)
206      brw_nir_analyze_boolean_resolves(nir);
207
208   nir_sweep(nir);
209
210   if (unlikely(debug_enabled)) {
211      fprintf(stderr, "NIR (final form) for %s shader:\n",
212              _mesa_shader_stage_to_string(stage));
213      nir_print_shader(nir, stderr);
214   }
215
216   return nir;
217}
218
219enum brw_reg_type
220brw_type_for_nir_type(nir_alu_type type)
221{
222   switch (type) {
223   case nir_type_unsigned:
224      return BRW_REGISTER_TYPE_UD;
225   case nir_type_bool:
226   case nir_type_int:
227      return BRW_REGISTER_TYPE_D;
228   case nir_type_float:
229      return BRW_REGISTER_TYPE_F;
230   default:
231      unreachable("unknown type");
232   }
233
234   return BRW_REGISTER_TYPE_F;
235}
236
237/* Returns the glsl_base_type corresponding to a nir_alu_type.
238 * This is used by both brw_vec4_nir and brw_fs_nir.
239 */
240enum glsl_base_type
241brw_glsl_base_type_for_nir_type(nir_alu_type type)
242{
243   switch (type) {
244   case nir_type_float:
245      return GLSL_TYPE_FLOAT;
246
247   case nir_type_int:
248      return GLSL_TYPE_INT;
249
250   case nir_type_unsigned:
251      return GLSL_TYPE_UINT;
252
253   default:
254      unreachable("bad type");
255   }
256}
257