brw_nir.c revision 864907e2f14523c130e6ff24c081789bb079bae1 
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{
66   struct gl_context *ctx = &brw->ctx;
67   const nir_shader_compiler_options *options =
68      ctx->Const.ShaderCompilerOptions[stage].NirOptions;
69   struct gl_shader *shader = shader_prog ? shader_prog->_LinkedShaders[stage] : NULL;
70   bool debug_enabled = INTEL_DEBUG & intel_debug_flag_for_shader_stage(stage);
71   nir_shader *nir;
72
73   /* First, lower the GLSL IR or Mesa IR to NIR */
74   if (shader_prog) {
75      nir = glsl_to_nir(shader, options);
76   } else {
77      nir = prog_to_nir(prog, options);
78      nir_convert_to_ssa(nir); /* turn registers into SSA */
79   }
80   nir_validate_shader(nir);
81
82   nir_lower_global_vars_to_local(nir);
83   nir_validate_shader(nir);
84
85   nir_lower_tex_projector(nir);
86   nir_validate_shader(nir);
87
88   nir_normalize_cubemap_coords(nir);
89   nir_validate_shader(nir);
90
91   nir_split_var_copies(nir);
92   nir_validate_shader(nir);
93
94   nir_optimize(nir);
95
96   /* Lower a bunch of stuff */
97   nir_lower_var_copies(nir);
98   nir_validate_shader(nir);
99
100   /* Get rid of split copies */
101   nir_optimize(nir);
102
103   nir_assign_var_locations_scalar_direct_first(nir, &nir->uniforms,
104                                                &nir->num_direct_uniforms,
105                                                &nir->num_uniforms);
106   nir_assign_var_locations_scalar(&nir->inputs, &nir->num_inputs);
107   nir_assign_var_locations_scalar(&nir->outputs, &nir->num_outputs);
108
109   nir_lower_io(nir);
110   nir_validate_shader(nir);
111
112   nir_remove_dead_variables(nir);
113   nir_validate_shader(nir);
114
115   if (shader_prog) {
116      nir_lower_samplers(nir, shader_prog, stage);
117      nir_validate_shader(nir);
118   }
119
120   nir_lower_system_values(nir);
121   nir_validate_shader(nir);
122
123   nir_lower_atomics(nir);
124   nir_validate_shader(nir);
125
126   nir_optimize(nir);
127
128   if (brw->gen >= 6) {
129      /* Try and fuse multiply-adds */
130      nir_opt_peephole_ffma(nir);
131      nir_validate_shader(nir);
132   }
133
134   nir_opt_algebraic_late(nir);
135   nir_validate_shader(nir);
136
137   nir_lower_locals_to_regs(nir);
138   nir_validate_shader(nir);
139
140   nir_lower_to_source_mods(nir);
141   nir_validate_shader(nir);
142   nir_copy_prop(nir);
143   nir_validate_shader(nir);
144   nir_opt_dce(nir);
145   nir_validate_shader(nir);
146
147   if (unlikely(debug_enabled)) {
148      /* Re-index SSA defs so we print more sensible numbers. */
149      nir_foreach_overload(nir, overload) {
150         if (overload->impl)
151            nir_index_ssa_defs(overload->impl);
152      }
153
154      fprintf(stderr, "NIR (SSA form) for %s shader:\n",
155              _mesa_shader_stage_to_string(stage));
156      nir_print_shader(nir, stderr);
157   }
158
159   nir_convert_from_ssa(nir, true);
160   nir_validate_shader(nir);
161
162   /* This is the last pass we run before we start emitting stuff.  It
163    * determines when we need to insert boolean resolves on Gen <= 5.  We
164    * run it last because it stashes data in instr->pass_flags and we don't
165    * want that to be squashed by other NIR passes.
166    */
167   if (brw->gen <= 5)
168      brw_nir_analyze_boolean_resolves(nir);
169
170   nir_sweep(nir);
171
172   if (unlikely(debug_enabled)) {
173      fprintf(stderr, "NIR (final form) for %s shader:\n",
174              _mesa_shader_stage_to_string(stage));
175      nir_print_shader(nir, stderr);
176   }
177
178   return nir;
179}
180