brw_nir.c revision db8a6de571bb72ef43209a415e5492001a87b1d8 
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, bool is_scalar)
31{
32   bool progress;
33   do {
34      progress = false;
35      nir_lower_vars_to_ssa(nir);
36      nir_validate_shader(nir);
37
38      if (is_scalar) {
39         nir_lower_alu_to_scalar(nir);
40         nir_validate_shader(nir);
41      }
42
43      progress |= nir_copy_prop(nir);
44      nir_validate_shader(nir);
45      nir_lower_phis_to_scalar(nir);
46      nir_validate_shader(nir);
47      progress |= nir_copy_prop(nir);
48      nir_validate_shader(nir);
49      progress |= nir_opt_dce(nir);
50      nir_validate_shader(nir);
51      progress |= nir_opt_cse(nir);
52      nir_validate_shader(nir);
53      progress |= nir_opt_peephole_select(nir);
54      nir_validate_shader(nir);
55      progress |= nir_opt_algebraic(nir);
56      nir_validate_shader(nir);
57      progress |= nir_opt_constant_folding(nir);
58      nir_validate_shader(nir);
59      progress |= nir_opt_remove_phis(nir);
60      nir_validate_shader(nir);
61   } while (progress);
62}
63
64nir_shader *
65brw_create_nir(struct brw_context *brw,
66               const struct gl_shader_program *shader_prog,
67               const struct gl_program *prog,
68               gl_shader_stage stage,
69               bool is_scalar)
70{
71   struct gl_context *ctx = &brw->ctx;
72   const nir_shader_compiler_options *options =
73      ctx->Const.ShaderCompilerOptions[stage].NirOptions;
74   struct gl_shader *shader = shader_prog ? shader_prog->_LinkedShaders[stage] : NULL;
75   bool debug_enabled = INTEL_DEBUG & intel_debug_flag_for_shader_stage(stage);
76   nir_shader *nir;
77
78   /* First, lower the GLSL IR or Mesa IR to NIR */
79   if (shader_prog) {
80      nir = glsl_to_nir(shader, options);
81   } else {
82      nir = prog_to_nir(prog, options);
83      nir_convert_to_ssa(nir); /* turn registers into SSA */
84   }
85   nir_validate_shader(nir);
86
87   nir_lower_global_vars_to_local(nir);
88   nir_validate_shader(nir);
89
90   nir_lower_tex_projector(nir);
91   nir_validate_shader(nir);
92
93   nir_normalize_cubemap_coords(nir);
94   nir_validate_shader(nir);
95
96   nir_split_var_copies(nir);
97   nir_validate_shader(nir);
98
99   nir_optimize(nir, is_scalar);
100
101   /* Lower a bunch of stuff */
102   nir_lower_var_copies(nir);
103   nir_validate_shader(nir);
104
105   /* Get rid of split copies */
106   nir_optimize(nir, is_scalar);
107
108   if (is_scalar) {
109      nir_assign_var_locations_direct_first(nir, &nir->uniforms,
110                                            &nir->num_direct_uniforms,
111                                            &nir->num_uniforms,
112                                            is_scalar);
113      nir_assign_var_locations(&nir->outputs, &nir->num_outputs, is_scalar);
114   } else {
115      nir_assign_var_locations(&nir->uniforms,
116                               &nir->num_uniforms,
117                               is_scalar);
118
119      foreach_list_typed(nir_variable, var, node, &nir->outputs)
120         var->data.driver_location = var->data.location;
121   }
122   nir_assign_var_locations(&nir->inputs, &nir->num_inputs, is_scalar);
123
124   nir_lower_io(nir, is_scalar);
125
126   nir_validate_shader(nir);
127
128   nir_remove_dead_variables(nir);
129   nir_validate_shader(nir);
130
131   if (shader_prog) {
132      nir_lower_samplers(nir, shader_prog, stage);
133      nir_validate_shader(nir);
134   }
135
136   nir_lower_system_values(nir);
137   nir_validate_shader(nir);
138
139   nir_lower_atomics(nir);
140   nir_validate_shader(nir);
141
142   nir_optimize(nir, is_scalar);
143
144   if (brw->gen >= 6) {
145      /* Try and fuse multiply-adds */
146      nir_opt_peephole_ffma(nir);
147      nir_validate_shader(nir);
148   }
149
150   nir_opt_algebraic_late(nir);
151   nir_validate_shader(nir);
152
153   nir_lower_locals_to_regs(nir);
154   nir_validate_shader(nir);
155
156   nir_lower_to_source_mods(nir);
157   nir_validate_shader(nir);
158   nir_copy_prop(nir);
159   nir_validate_shader(nir);
160   nir_opt_dce(nir);
161   nir_validate_shader(nir);
162
163   if (unlikely(debug_enabled)) {
164      /* Re-index SSA defs so we print more sensible numbers. */
165      nir_foreach_overload(nir, overload) {
166         if (overload->impl)
167            nir_index_ssa_defs(overload->impl);
168      }
169
170      fprintf(stderr, "NIR (SSA form) for %s shader:\n",
171              _mesa_shader_stage_to_string(stage));
172      nir_print_shader(nir, stderr);
173   }
174
175   nir_convert_from_ssa(nir, is_scalar);
176   nir_validate_shader(nir);
177
178   if (!is_scalar) {
179      nir_lower_vec_to_movs(nir);
180      nir_validate_shader(nir);
181   }
182
183   /* This is the last pass we run before we start emitting stuff.  It
184    * determines when we need to insert boolean resolves on Gen <= 5.  We
185    * run it last because it stashes data in instr->pass_flags and we don't
186    * want that to be squashed by other NIR passes.
187    */
188   if (brw->gen <= 5)
189      brw_nir_analyze_boolean_resolves(nir);
190
191   nir_sweep(nir);
192
193   if (unlikely(debug_enabled)) {
194      fprintf(stderr, "NIR (final form) for %s shader:\n",
195              _mesa_shader_stage_to_string(stage));
196      nir_print_shader(nir, stderr);
197   }
198
199   return nir;
200}
201
202enum brw_reg_type
203brw_type_for_nir_type(nir_alu_type type)
204{
205   switch (type) {
206   case nir_type_unsigned:
207      return BRW_REGISTER_TYPE_UD;
208   case nir_type_bool:
209   case nir_type_int:
210      return BRW_REGISTER_TYPE_D;
211   case nir_type_float:
212      return BRW_REGISTER_TYPE_F;
213   default:
214      unreachable("unknown type");
215   }
216
217   return BRW_REGISTER_TYPE_F;
218}
219
220/* Returns the glsl_base_type corresponding to a nir_alu_type.
221 * This is used by both brw_vec4_nir and brw_fs_nir.
222 */
223enum glsl_base_type
224brw_glsl_base_type_for_nir_type(nir_alu_type type)
225{
226   switch (type) {
227   case nir_type_float:
228      return GLSL_TYPE_FLOAT;
229
230   case nir_type_int:
231      return GLSL_TYPE_INT;
232
233   case nir_type_unsigned:
234      return GLSL_TYPE_UINT;
235
236   default:
237      unreachable("bad type");
238   }
239}
240