ir_variable.cpp

   1 /*
   2  * Copyright © 2010 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
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 #include "glsl_parser_extras.h"
  25 #include "glsl_symbol_table.h"
  26 #include "ir.h"
  27 #include "builtin_variables.h"
  28
  29 #ifndef Elements
  30 #define Elements(x) (sizeof(x)/sizeof(*(x)))
  31 #endif
  32
  33 static void
  34 add_builtin_variable(const builtin_variable *proto, exec_list *instructions,
  35                      glsl_symbol_table *symtab)
  36 {
  37    /* Create a new variable declaration from the description supplied by
  38     * the caller.
  39     */
  40    const glsl_type *const type = symtab->get_type(proto->type);
  41
  42    assert(type != NULL);
  43
  44    ir_variable *var = new ir_variable(type, proto->name);
  45
  46    var->mode = proto->mode;
  47    if (var->mode != ir_var_out)
  48       var->read_only = true;
  49
  50
  51    /* Once the variable is created an initialized, add it to the symbol table
  52     * and add the declaration to the IR stream.
  53     */
  54    instructions->push_tail(var);
  55
  56    symtab->add_variable(var->name, var);
  57 }
  58
  59
  60 static void
  61 generate_110_vs_variables(exec_list *instructions,
  62                           glsl_symbol_table *symtab)
  63 {
  64    for (unsigned i = 0; i < Elements(builtin_core_vs_variables); i++) {
  65       add_builtin_variable(& builtin_core_vs_variables[i],
  66                            instructions, symtab);
  67    }
  68
  69    for (unsigned i = 0
  70            ; i < Elements(builtin_110_deprecated_vs_variables)
  71            ; i++) {
  72       add_builtin_variable(& builtin_110_deprecated_vs_variables[i],
  73                            instructions, symtab);
  74    }
  75
  76    /* FINISHME: Add support fo gl_TexCoord.  The size of this array is
  77     * FINISHME: implementation dependent based on the value of
  78     * FINISHME: GL_MAX_TEXTURE_COORDS.
  79     */
  80 }
  81
  82
  83 static void
  84 generate_120_vs_variables(exec_list *instructions,
  85                           glsl_symbol_table *symtab)
  86 {
  87    /* GLSL version 1.20 did not add any built-in variables in the vertex
  88     * shader.
  89     */
  90    generate_110_vs_variables(instructions, symtab);
  91 }
  92
  93
  94 static void
  95 generate_130_vs_variables(exec_list *instructions,
  96                           glsl_symbol_table *symtab)
  97 {
  98    generate_120_vs_variables(instructions, symtab);
  99
 100    for (unsigned i = 0; i < Elements(builtin_130_vs_variables); i++) {
 101       add_builtin_variable(& builtin_130_vs_variables[i],
 102                            instructions, symtab);
 103    }
 104
 105    /* FINISHME: Add support fo gl_ClipDistance.  The size of this array is
 106     * FINISHME: implementation dependent based on the value of
 107     * FINISHME: GL_MAX_CLIP_DISTANCES.
 108     */
 109 }
 110
 111
 112 static void
 113 initialize_vs_variables(exec_list *instructions,
 114                         struct _mesa_glsl_parse_state *state)
 115 {
 116
 117    switch (state->language_version) {
 118    case 110:
 119       generate_110_vs_variables(instructions, state->symbols);
 120       break;
 121    case 120:
 122       generate_120_vs_variables(instructions, state->symbols);
 123       break;
 124    case 130:
 125       generate_130_vs_variables(instructions, state->symbols);
 126       break;
 127    }
 128 }
 129
 130
 131 void
 132 _mesa_glsl_initialize_variables(exec_list *instructions,
 133                                 struct _mesa_glsl_parse_state *state)
 134 {
 135    switch (state->target) {
 136    case vertex_shader:
 137       initialize_vs_variables(instructions, state);
 138       break;
 139    case geometry_shader:
 140    case fragment_shader:
 141       break;
 142    }
 143 }