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 "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                      struct _mesa_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 = (glsl_type *)
  41       _mesa_symbol_table_find_symbol(symtab, 0, proto->type);
  42
  43    assert(type != NULL);
  44
  45    ir_variable *var = new ir_variable(type, proto->name);
  46
  47    var->mode = proto->mode;
  48    if (var->mode != ir_var_out)
  49       var->read_only = true;
  50
  51
  52    /* Once the variable is created an initialized, add it to the symbol table
  53     * and add the declaration to the IR stream.
  54     */
  55    instructions->push_tail(var);
  56
  57    _mesa_symbol_table_add_symbol(symtab, 0, var->name, var);
  58 }
  59
  60
  61 static void
  62 generate_110_vs_variables(exec_list *instructions,
  63                           struct _mesa_symbol_table *symtab)
  64 {
  65    for (unsigned i = 0; i < Elements(builtin_core_vs_variables); i++) {
  66       add_builtin_variable(& builtin_core_vs_variables[i],
  67                            instructions, symtab);
  68    }
  69
  70    for (unsigned i = 0
  71            ; i < Elements(builtin_110_deprecated_vs_variables)
  72            ; i++) {
  73       add_builtin_variable(& builtin_110_deprecated_vs_variables[i],
  74                            instructions, symtab);
  75    }
  76
  77    /* FINISHME: Add support fo gl_TexCoord.  The size of this array is
  78     * FINISHME: implementation dependent based on the value of
  79     * FINISHME: GL_MAX_TEXTURE_COORDS.
  80     */
  81 }
  82
  83
  84 static void
  85 generate_120_vs_variables(exec_list *instructions,
  86                           struct _mesa_symbol_table *symtab)
  87 {
  88    /* GLSL version 1.20 did not add any built-in variables in the vertex
  89     * shader.
  90     */
  91    generate_110_vs_variables(instructions, symtab);
  92 }
  93
  94
  95 static void
  96 generate_130_vs_variables(exec_list *instructions,
  97                           struct _mesa_symbol_table *symtab)
  98 {
  99    generate_120_vs_variables(instructions, symtab);
 100
 101    for (unsigned i = 0; i < Elements(builtin_130_vs_variables); i++) {
 102       add_builtin_variable(& builtin_130_vs_variables[i],
 103                            instructions, symtab);
 104    }
 105
 106    /* FINISHME: Add support fo gl_ClipDistance.  The size of this array is
 107     * FINISHME: implementation dependent based on the value of
 108     * FINISHME: GL_MAX_CLIP_DISTANCES.
 109     */
 110 }
 111
 112
 113 static void
 114 initialize_vs_variables(exec_list *instructions,
 115                         struct _mesa_glsl_parse_state *state)
 116 {
 117
 118    switch (state->language_version) {
 119    case 110:
 120       generate_110_vs_variables(instructions, state->symbols);
 121       break;
 122    case 120:
 123       generate_120_vs_variables(instructions, state->symbols);
 124       break;
 125    case 130:
 126       generate_130_vs_variables(instructions, state->symbols);
 127       break;
 128    }
 129 }
 130
 131
 132 void
 133 _mesa_glsl_initialize_variables(exec_list *instructions,
 134                                 struct _mesa_glsl_parse_state *state)
 135 {
 136    switch (state->target) {
 137    case vertex_shader:
 138       initialize_vs_variables(instructions, state);
 139       break;
 140    case geometry_shader:
 141    case fragment_shader:
 142       break;
 143    }
 144 }