src/compiler/nir/nir_lower_constant_initializers.c

   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
  27 static void
  28 build_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       load->value = c->values[0];
  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          load->value = c->values[i];
  46          nir_builder_instr_insert(b, &load->instr);
  47          nir_store_deref(b, nir_build_deref_array(b, deref, nir_imm_int(b, 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(b, deref, nir_imm_int(b, i)),
  62                              c->elements[i]);
  63       }
  64    }
  65 }
  66
  67 static bool
  68 lower_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
  89 bool
  90 nir_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 }