brw_nir.c revision 6e58fc56a5a396020cd299db11895120ec3da520 
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 "glsl/glsl_parser_extras.h"
26#include "glsl/nir/glsl_to_nir.h"
27#include "program/prog_to_nir.h"
28
29static void
30nir_optimize(nir_shader *nir)
31{
32   bool progress;
33   do {
34      progress = false;
35      nir_lower_vars_to_ssa(nir);
36      nir_validate_shader(nir);
37      nir_lower_alu_to_scalar(nir);
38      nir_validate_shader(nir);
39      progress |= nir_copy_prop(nir);
40      nir_validate_shader(nir);
41      nir_lower_phis_to_scalar(nir);
42      nir_validate_shader(nir);
43      progress |= nir_copy_prop(nir);
44      nir_validate_shader(nir);
45      progress |= nir_opt_dce(nir);
46      nir_validate_shader(nir);
47      progress |= nir_opt_cse(nir);
48      nir_validate_shader(nir);
49      progress |= nir_opt_peephole_select(nir);
50      nir_validate_shader(nir);
51      progress |= nir_opt_algebraic(nir);
52      nir_validate_shader(nir);
53      progress |= nir_opt_constant_folding(nir);
54      nir_validate_shader(nir);
55      progress |= nir_opt_remove_phis(nir);
56      nir_validate_shader(nir);
57   } while (progress);
58}
59
60nir_shader *
61brw_create_nir(struct brw_context *brw,
62               const struct gl_shader_program *shader_prog,
63               const struct gl_program *prog,
64               gl_shader_stage stage,
65               bool is_scalar)
66{
67   struct gl_context *ctx = &brw->ctx;
68   const nir_shader_compiler_options *options =
69      ctx->Const.ShaderCompilerOptions[stage].NirOptions;
70   struct gl_shader *shader = shader_prog ? shader_prog->_LinkedShaders[stage] : NULL;
71   bool debug_enabled = INTEL_DEBUG & intel_debug_flag_for_shader_stage(stage);
72   nir_shader *nir;
73
74   /* First, lower the GLSL IR or Mesa IR to NIR */
75   if (shader_prog) {
76      nir = glsl_to_nir(shader, options);
77   } else {
78      nir = prog_to_nir(prog, options);
79      nir_convert_to_ssa(nir); /* turn registers into SSA */
80   }
81   nir_validate_shader(nir);
82
83   nir_lower_global_vars_to_local(nir);
84   nir_validate_shader(nir);
85
86   nir_lower_tex_projector(nir);
87   nir_validate_shader(nir);
88
89   nir_normalize_cubemap_coords(nir);
90   nir_validate_shader(nir);
91
92   nir_split_var_copies(nir);
93   nir_validate_shader(nir);
94
95   nir_optimize(nir);
96
97   /* Lower a bunch of stuff */
98   nir_lower_var_copies(nir);
99   nir_validate_shader(nir);
100
101   /* Get rid of split copies */
102   nir_optimize(nir);
103
104   if (is_scalar) {
105      nir_assign_var_locations_direct_first(nir, &nir->uniforms,
106                                            &nir->num_direct_uniforms,
107                                            &nir->num_uniforms,
108                                            is_scalar);
109   } else {
110      nir_assign_var_locations(&nir->uniforms,
111                               &nir->num_uniforms,
112                               is_scalar);
113   }
114   nir_assign_var_locations(&nir->inputs, &nir->num_inputs, is_scalar);
115   nir_assign_var_locations(&nir->outputs, &nir->num_outputs, is_scalar);
116
117   nir_lower_io(nir, is_scalar);
118
119   nir_validate_shader(nir);
120
121   nir_remove_dead_variables(nir);
122   nir_validate_shader(nir);
123
124   if (shader_prog) {
125      nir_lower_samplers(nir, shader_prog, stage);
126      nir_validate_shader(nir);
127   }
128
129   nir_lower_system_values(nir);
130   nir_validate_shader(nir);
131
132   nir_lower_atomics(nir);
133   nir_validate_shader(nir);
134
135   nir_optimize(nir);
136
137   if (brw->gen >= 6) {
138      /* Try and fuse multiply-adds */
139      nir_opt_peephole_ffma(nir);
140      nir_validate_shader(nir);
141   }
142
143   nir_opt_algebraic_late(nir);
144   nir_validate_shader(nir);
145
146   nir_lower_locals_to_regs(nir);
147   nir_validate_shader(nir);
148
149   nir_lower_to_source_mods(nir);
150   nir_validate_shader(nir);
151   nir_copy_prop(nir);
152   nir_validate_shader(nir);
153   nir_opt_dce(nir);
154   nir_validate_shader(nir);
155
156   if (unlikely(debug_enabled)) {
157      /* Re-index SSA defs so we print more sensible numbers. */
158      nir_foreach_overload(nir, overload) {
159         if (overload->impl)
160            nir_index_ssa_defs(overload->impl);
161      }
162
163      fprintf(stderr, "NIR (SSA form) for %s shader:\n",
164              _mesa_shader_stage_to_string(stage));
165      nir_print_shader(nir, stderr);
166   }
167
168   nir_convert_from_ssa(nir, true);
169   nir_validate_shader(nir);
170
171   /* This is the last pass we run before we start emitting stuff.  It
172    * determines when we need to insert boolean resolves on Gen <= 5.  We
173    * run it last because it stashes data in instr->pass_flags and we don't
174    * want that to be squashed by other NIR passes.
175    */
176   if (brw->gen <= 5)
177      brw_nir_analyze_boolean_resolves(nir);
178
179   nir_sweep(nir);
180
181   if (unlikely(debug_enabled)) {
182      fprintf(stderr, "NIR (final form) for %s shader:\n",
183              _mesa_shader_stage_to_string(stage));
184      nir_print_shader(nir, stderr);
185   }
186
187   return nir;
188}
189