1/*
2 * Copyright © 2016 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 "nir.h"
25#include "nir_builder.h"
26
27static void
28build_constant_load(nir_builder *b, nir_deref_instr *deref, nir_constant *c)
29{
30   if (glsl_type_is_vector_or_scalar(deref->type)) {
31      nir_load_const_instr *load =
32         nir_load_const_instr_create(b->shader,
33                                     glsl_get_vector_elements(deref->type),
34                                     glsl_get_bit_size(deref->type));
35      memcpy(load->value, c->values[0], sizeof(*load->value) * load->def.num_components);
36      nir_builder_instr_insert(b, &load->instr);
37      nir_store_deref(b, deref, &load->def, ~0);
38   } else if (glsl_type_is_matrix(deref->type)) {
39      unsigned cols = glsl_get_matrix_columns(deref->type);
40      unsigned rows = glsl_get_vector_elements(deref->type);
41      unsigned bit_size = glsl_get_bit_size(deref->type);
42      for (unsigned i = 0; i < cols; i++) {
43         nir_load_const_instr *load =
44            nir_load_const_instr_create(b->shader, rows, bit_size);
45         memcpy(load->value, c->values[i], sizeof(*load->value) * load->def.num_components);
46         nir_builder_instr_insert(b, &load->instr);
47         nir_store_deref(b, nir_build_deref_array_imm(b, deref, i),
48                         &load->def, ~0);
49      }
50   } else if (glsl_type_is_struct_or_ifc(deref->type)) {
51      unsigned len = glsl_get_length(deref->type);
52      for (unsigned i = 0; i < len; i++) {
53         build_constant_load(b, nir_build_deref_struct(b, deref, i),
54                             c->elements[i]);
55      }
56   } else {
57      assert(glsl_type_is_array(deref->type));
58      unsigned len = glsl_get_length(deref->type);
59      for (unsigned i = 0; i < len; i++) {
60         build_constant_load(b,
61                             nir_build_deref_array_imm(b, deref, i),
62                             c->elements[i]);
63      }
64   }
65}
66
67static bool
68lower_const_initializer(struct nir_builder *b, struct exec_list *var_list)
69{
70   bool progress = false;
71
72   b->cursor = nir_before_cf_list(&b->impl->body);
73
74   nir_foreach_variable(var, var_list) {
75      if (!var->constant_initializer)
76         continue;
77
78      progress = true;
79
80      build_constant_load(b, nir_build_deref_var(b, var),
81                          var->constant_initializer);
82
83      var->constant_initializer = NULL;
84   }
85
86   return progress;
87}
88
89bool
90nir_lower_constant_initializers(nir_shader *shader, nir_variable_mode modes)
91{
92   bool progress = false;
93
94   nir_foreach_function(function, shader) {
95      if (!function->impl)
96	 continue;
97
98      bool impl_progress = false;
99
100      nir_builder builder;
101      nir_builder_init(&builder, function->impl);
102
103      if ((modes & nir_var_shader_out) && function->is_entrypoint)
104         impl_progress |= lower_const_initializer(&builder, &shader->outputs);
105
106      if ((modes & nir_var_shader_temp) && function->is_entrypoint)
107         impl_progress |= lower_const_initializer(&builder, &shader->globals);
108
109      if ((modes & nir_var_system_value) && function->is_entrypoint)
110         impl_progress |= lower_const_initializer(&builder, &shader->system_values);
111
112      if (modes & nir_var_function_temp)
113         impl_progress |= lower_const_initializer(&builder, &function->impl->locals);
114
115      if (impl_progress) {
116         progress = true;
117         nir_metadata_preserve(function->impl, nir_metadata_block_index |
118                                               nir_metadata_dominance |
119                                               nir_metadata_live_ssa_defs);
120      } else {
121#ifndef NDEBUG
122         function->impl->valid_metadata &= ~nir_metadata_not_properly_reset;
123#endif
124      }
125   }
126
127   return progress;
128}
129