src/glsl/builtin_variables.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 "ir.h"
  25 #include "glsl_parser_extras.h"
  26 #include "glsl_symbol_table.h"
  27 #include "main/core.h"
  28 #include "main/uniforms.h"
  29 #include "program/prog_statevars.h"
  30 #include "program/prog_instruction.h"
  31
  32 static const struct gl_builtin_uniform_element gl_NumSamples_elements[] = {
  33    {NULL, {STATE_NUM_SAMPLES, 0, 0}, SWIZZLE_XXXX}
  34 };
  35
  36 static const struct gl_builtin_uniform_element gl_DepthRange_elements[] = {
  37    {"near", {STATE_DEPTH_RANGE, 0, 0}, SWIZZLE_XXXX},
  38    {"far", {STATE_DEPTH_RANGE, 0, 0}, SWIZZLE_YYYY},
  39    {"diff", {STATE_DEPTH_RANGE, 0, 0}, SWIZZLE_ZZZZ},
  40 };
  41
  42 static const struct gl_builtin_uniform_element gl_ClipPlane_elements[] = {
  43    {NULL, {STATE_CLIPPLANE, 0, 0}, SWIZZLE_XYZW}
  44 };
  45
  46 static const struct gl_builtin_uniform_element gl_Point_elements[] = {
  47    {"size", {STATE_POINT_SIZE}, SWIZZLE_XXXX},
  48    {"sizeMin", {STATE_POINT_SIZE}, SWIZZLE_YYYY},
  49    {"sizeMax", {STATE_POINT_SIZE}, SWIZZLE_ZZZZ},
  50    {"fadeThresholdSize", {STATE_POINT_SIZE}, SWIZZLE_WWWW},
  51    {"distanceConstantAttenuation", {STATE_POINT_ATTENUATION}, SWIZZLE_XXXX},
  52    {"distanceLinearAttenuation", {STATE_POINT_ATTENUATION}, SWIZZLE_YYYY},
  53    {"distanceQuadraticAttenuation", {STATE_POINT_ATTENUATION}, SWIZZLE_ZZZZ},
  54 };
  55
  56 static const struct gl_builtin_uniform_element gl_FrontMaterial_elements[] = {
  57    {"emission", {STATE_MATERIAL, 0, STATE_EMISSION}, SWIZZLE_XYZW},
  58    {"ambient", {STATE_MATERIAL, 0, STATE_AMBIENT}, SWIZZLE_XYZW},
  59    {"diffuse", {STATE_MATERIAL, 0, STATE_DIFFUSE}, SWIZZLE_XYZW},
  60    {"specular", {STATE_MATERIAL, 0, STATE_SPECULAR}, SWIZZLE_XYZW},
  61    {"shininess", {STATE_MATERIAL, 0, STATE_SHININESS}, SWIZZLE_XXXX},
  62 };
  63
  64 static const struct gl_builtin_uniform_element gl_BackMaterial_elements[] = {
  65    {"emission", {STATE_MATERIAL, 1, STATE_EMISSION}, SWIZZLE_XYZW},
  66    {"ambient", {STATE_MATERIAL, 1, STATE_AMBIENT}, SWIZZLE_XYZW},
  67    {"diffuse", {STATE_MATERIAL, 1, STATE_DIFFUSE}, SWIZZLE_XYZW},
  68    {"specular", {STATE_MATERIAL, 1, STATE_SPECULAR}, SWIZZLE_XYZW},
  69    {"shininess", {STATE_MATERIAL, 1, STATE_SHININESS}, SWIZZLE_XXXX},
  70 };
  71
  72 static const struct gl_builtin_uniform_element gl_LightSource_elements[] = {
  73    {"ambient", {STATE_LIGHT, 0, STATE_AMBIENT}, SWIZZLE_XYZW},
  74    {"diffuse", {STATE_LIGHT, 0, STATE_DIFFUSE}, SWIZZLE_XYZW},
  75    {"specular", {STATE_LIGHT, 0, STATE_SPECULAR}, SWIZZLE_XYZW},
  76    {"position", {STATE_LIGHT, 0, STATE_POSITION}, SWIZZLE_XYZW},
  77    {"halfVector", {STATE_LIGHT, 0, STATE_HALF_VECTOR}, SWIZZLE_XYZW},
  78    {"spotDirection", {STATE_LIGHT, 0, STATE_SPOT_DIRECTION},
  79     MAKE_SWIZZLE4(SWIZZLE_X,
  80                   SWIZZLE_Y,
  81                   SWIZZLE_Z,
  82                   SWIZZLE_Z)},
  83    {"spotCosCutoff", {STATE_LIGHT, 0, STATE_SPOT_DIRECTION}, SWIZZLE_WWWW},
  84    {"spotCutoff", {STATE_LIGHT, 0, STATE_SPOT_CUTOFF}, SWIZZLE_XXXX},
  85    {"spotExponent", {STATE_LIGHT, 0, STATE_ATTENUATION}, SWIZZLE_WWWW},
  86    {"constantAttenuation", {STATE_LIGHT, 0, STATE_ATTENUATION}, SWIZZLE_XXXX},
  87    {"linearAttenuation", {STATE_LIGHT, 0, STATE_ATTENUATION}, SWIZZLE_YYYY},
  88    {"quadraticAttenuation", {STATE_LIGHT, 0, STATE_ATTENUATION}, SWIZZLE_ZZZZ},
  89 };
  90
  91 static const struct gl_builtin_uniform_element gl_LightModel_elements[] = {
  92    {"ambient", {STATE_LIGHTMODEL_AMBIENT, 0}, SWIZZLE_XYZW},
  93 };
  94
  95 static const struct gl_builtin_uniform_element gl_FrontLightModelProduct_elements[] = {
  96    {"sceneColor", {STATE_LIGHTMODEL_SCENECOLOR, 0}, SWIZZLE_XYZW},
  97 };
  98
  99 static const struct gl_builtin_uniform_element gl_BackLightModelProduct_elements[] = {
 100    {"sceneColor", {STATE_LIGHTMODEL_SCENECOLOR, 1}, SWIZZLE_XYZW},
 101 };
 102
 103 static const struct gl_builtin_uniform_element gl_FrontLightProduct_elements[] = {
 104    {"ambient", {STATE_LIGHTPROD, 0, 0, STATE_AMBIENT}, SWIZZLE_XYZW},
 105    {"diffuse", {STATE_LIGHTPROD, 0, 0, STATE_DIFFUSE}, SWIZZLE_XYZW},
 106    {"specular", {STATE_LIGHTPROD, 0, 0, STATE_SPECULAR}, SWIZZLE_XYZW},
 107 };
 108
 109 static const struct gl_builtin_uniform_element gl_BackLightProduct_elements[] = {
 110    {"ambient", {STATE_LIGHTPROD, 0, 1, STATE_AMBIENT}, SWIZZLE_XYZW},
 111    {"diffuse", {STATE_LIGHTPROD, 0, 1, STATE_DIFFUSE}, SWIZZLE_XYZW},
 112    {"specular", {STATE_LIGHTPROD, 0, 1, STATE_SPECULAR}, SWIZZLE_XYZW},
 113 };
 114
 115 static const struct gl_builtin_uniform_element gl_TextureEnvColor_elements[] = {
 116    {NULL, {STATE_TEXENV_COLOR, 0}, SWIZZLE_XYZW},
 117 };
 118
 119 static const struct gl_builtin_uniform_element gl_EyePlaneS_elements[] = {
 120    {NULL, {STATE_TEXGEN, 0, STATE_TEXGEN_EYE_S}, SWIZZLE_XYZW},
 121 };
 122
 123 static const struct gl_builtin_uniform_element gl_EyePlaneT_elements[] = {
 124    {NULL, {STATE_TEXGEN, 0, STATE_TEXGEN_EYE_T}, SWIZZLE_XYZW},
 125 };
 126
 127 static const struct gl_builtin_uniform_element gl_EyePlaneR_elements[] = {
 128    {NULL, {STATE_TEXGEN, 0, STATE_TEXGEN_EYE_R}, SWIZZLE_XYZW},
 129 };
 130
 131 static const struct gl_builtin_uniform_element gl_EyePlaneQ_elements[] = {
 132    {NULL, {STATE_TEXGEN, 0, STATE_TEXGEN_EYE_Q}, SWIZZLE_XYZW},
 133 };
 134
 135 static const struct gl_builtin_uniform_element gl_ObjectPlaneS_elements[] = {
 136    {NULL, {STATE_TEXGEN, 0, STATE_TEXGEN_OBJECT_S}, SWIZZLE_XYZW},
 137 };
 138
 139 static const struct gl_builtin_uniform_element gl_ObjectPlaneT_elements[] = {
 140    {NULL, {STATE_TEXGEN, 0, STATE_TEXGEN_OBJECT_T}, SWIZZLE_XYZW},
 141 };
 142
 143 static const struct gl_builtin_uniform_element gl_ObjectPlaneR_elements[] = {
 144    {NULL, {STATE_TEXGEN, 0, STATE_TEXGEN_OBJECT_R}, SWIZZLE_XYZW},
 145 };
 146
 147 static const struct gl_builtin_uniform_element gl_ObjectPlaneQ_elements[] = {
 148    {NULL, {STATE_TEXGEN, 0, STATE_TEXGEN_OBJECT_Q}, SWIZZLE_XYZW},
 149 };
 150
 151 static const struct gl_builtin_uniform_element gl_Fog_elements[] = {
 152    {"color", {STATE_FOG_COLOR}, SWIZZLE_XYZW},
 153    {"density", {STATE_FOG_PARAMS}, SWIZZLE_XXXX},
 154    {"start", {STATE_FOG_PARAMS}, SWIZZLE_YYYY},
 155    {"end", {STATE_FOG_PARAMS}, SWIZZLE_ZZZZ},
 156    {"scale", {STATE_FOG_PARAMS}, SWIZZLE_WWWW},
 157 };
 158
 159 static const struct gl_builtin_uniform_element gl_NormalScale_elements[] = {
 160    {NULL, {STATE_NORMAL_SCALE}, SWIZZLE_XXXX},
 161 };
 162
 163 static const struct gl_builtin_uniform_element gl_BumpRotMatrix0MESA_elements[] = {
 164    {NULL, {STATE_INTERNAL, STATE_ROT_MATRIX_0}, SWIZZLE_XYZW},
 165 };
 166
 167 static const struct gl_builtin_uniform_element gl_BumpRotMatrix1MESA_elements[] = {
 168    {NULL, {STATE_INTERNAL, STATE_ROT_MATRIX_1}, SWIZZLE_XYZW},
 169 };
 170
 171 static const struct gl_builtin_uniform_element gl_FogParamsOptimizedMESA_elements[] = {
 172    {NULL, {STATE_INTERNAL, STATE_FOG_PARAMS_OPTIMIZED}, SWIZZLE_XYZW},
 173 };
 174
 175 static const struct gl_builtin_uniform_element gl_CurrentAttribVertMESA_elements[] = {
 176    {NULL, {STATE_INTERNAL, STATE_CURRENT_ATTRIB, 0}, SWIZZLE_XYZW},
 177 };
 178
 179 static const struct gl_builtin_uniform_element gl_CurrentAttribFragMESA_elements[] = {
 180    {NULL, {STATE_INTERNAL, STATE_CURRENT_ATTRIB_MAYBE_VP_CLAMPED, 0}, SWIZZLE_XYZW},
 181 };
 182
 183 #define MATRIX(name, statevar, modifier)                                \
 184    static const struct gl_builtin_uniform_element name ## _elements[] = { \
 185       { NULL, { statevar, 0, 0, 0, modifier}, SWIZZLE_XYZW },           \
 186       { NULL, { statevar, 0, 1, 1, modifier}, SWIZZLE_XYZW },           \
 187       { NULL, { statevar, 0, 2, 2, modifier}, SWIZZLE_XYZW },           \
 188       { NULL, { statevar, 0, 3, 3, modifier}, SWIZZLE_XYZW },           \
 189    }
 190
 191 MATRIX(gl_ModelViewMatrix,
 192        STATE_MODELVIEW_MATRIX, STATE_MATRIX_TRANSPOSE);
 193 MATRIX(gl_ModelViewMatrixInverse,
 194        STATE_MODELVIEW_MATRIX, STATE_MATRIX_INVTRANS);
 195 MATRIX(gl_ModelViewMatrixTranspose,
 196        STATE_MODELVIEW_MATRIX, 0);
 197 MATRIX(gl_ModelViewMatrixInverseTranspose,
 198        STATE_MODELVIEW_MATRIX, STATE_MATRIX_INVERSE);
 199
 200 MATRIX(gl_ProjectionMatrix,
 201        STATE_PROJECTION_MATRIX, STATE_MATRIX_TRANSPOSE);
 202 MATRIX(gl_ProjectionMatrixInverse,
 203        STATE_PROJECTION_MATRIX, STATE_MATRIX_INVTRANS);
 204 MATRIX(gl_ProjectionMatrixTranspose,
 205        STATE_PROJECTION_MATRIX, 0);
 206 MATRIX(gl_ProjectionMatrixInverseTranspose,
 207        STATE_PROJECTION_MATRIX, STATE_MATRIX_INVERSE);
 208
 209 MATRIX(gl_ModelViewProjectionMatrix,
 210        STATE_MVP_MATRIX, STATE_MATRIX_TRANSPOSE);
 211 MATRIX(gl_ModelViewProjectionMatrixInverse,
 212        STATE_MVP_MATRIX, STATE_MATRIX_INVTRANS);
 213 MATRIX(gl_ModelViewProjectionMatrixTranspose,
 214        STATE_MVP_MATRIX, 0);
 215 MATRIX(gl_ModelViewProjectionMatrixInverseTranspose,
 216        STATE_MVP_MATRIX, STATE_MATRIX_INVERSE);
 217
 218 MATRIX(gl_TextureMatrix,
 219        STATE_TEXTURE_MATRIX, STATE_MATRIX_TRANSPOSE);
 220 MATRIX(gl_TextureMatrixInverse,
 221        STATE_TEXTURE_MATRIX, STATE_MATRIX_INVTRANS);
 222 MATRIX(gl_TextureMatrixTranspose,
 223        STATE_TEXTURE_MATRIX, 0);
 224 MATRIX(gl_TextureMatrixInverseTranspose,
 225        STATE_TEXTURE_MATRIX, STATE_MATRIX_INVERSE);
 226
 227 static const struct gl_builtin_uniform_element gl_NormalMatrix_elements[] = {
 228    { NULL, { STATE_MODELVIEW_MATRIX, 0, 0, 0, STATE_MATRIX_INVERSE},
 229      MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Z, SWIZZLE_Z) },
 230    { NULL, { STATE_MODELVIEW_MATRIX, 0, 1, 1, STATE_MATRIX_INVERSE},
 231      MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Z, SWIZZLE_Z) },
 232    { NULL, { STATE_MODELVIEW_MATRIX, 0, 2, 2, STATE_MATRIX_INVERSE},
 233      MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Z, SWIZZLE_Z) },
 234 };
 235
 236 #undef MATRIX
 237
 238 #define STATEVAR(name) {#name, name ## _elements, Elements(name ## _elements)}
 239
 240 static const struct gl_builtin_uniform_desc _mesa_builtin_uniform_desc[] = {
 241    STATEVAR(gl_NumSamples),
 242    STATEVAR(gl_DepthRange),
 243    STATEVAR(gl_ClipPlane),
 244    STATEVAR(gl_Point),
 245    STATEVAR(gl_FrontMaterial),
 246    STATEVAR(gl_BackMaterial),
 247    STATEVAR(gl_LightSource),
 248    STATEVAR(gl_LightModel),
 249    STATEVAR(gl_FrontLightModelProduct),
 250    STATEVAR(gl_BackLightModelProduct),
 251    STATEVAR(gl_FrontLightProduct),
 252    STATEVAR(gl_BackLightProduct),
 253    STATEVAR(gl_TextureEnvColor),
 254    STATEVAR(gl_EyePlaneS),
 255    STATEVAR(gl_EyePlaneT),
 256    STATEVAR(gl_EyePlaneR),
 257    STATEVAR(gl_EyePlaneQ),
 258    STATEVAR(gl_ObjectPlaneS),
 259    STATEVAR(gl_ObjectPlaneT),
 260    STATEVAR(gl_ObjectPlaneR),
 261    STATEVAR(gl_ObjectPlaneQ),
 262    STATEVAR(gl_Fog),
 263
 264    STATEVAR(gl_ModelViewMatrix),
 265    STATEVAR(gl_ModelViewMatrixInverse),
 266    STATEVAR(gl_ModelViewMatrixTranspose),
 267    STATEVAR(gl_ModelViewMatrixInverseTranspose),
 268
 269    STATEVAR(gl_ProjectionMatrix),
 270    STATEVAR(gl_ProjectionMatrixInverse),
 271    STATEVAR(gl_ProjectionMatrixTranspose),
 272    STATEVAR(gl_ProjectionMatrixInverseTranspose),
 273
 274    STATEVAR(gl_ModelViewProjectionMatrix),
 275    STATEVAR(gl_ModelViewProjectionMatrixInverse),
 276    STATEVAR(gl_ModelViewProjectionMatrixTranspose),
 277    STATEVAR(gl_ModelViewProjectionMatrixInverseTranspose),
 278
 279    STATEVAR(gl_TextureMatrix),
 280    STATEVAR(gl_TextureMatrixInverse),
 281    STATEVAR(gl_TextureMatrixTranspose),
 282    STATEVAR(gl_TextureMatrixInverseTranspose),
 283
 284    STATEVAR(gl_NormalMatrix),
 285    STATEVAR(gl_NormalScale),
 286
 287    STATEVAR(gl_BumpRotMatrix0MESA),
 288    STATEVAR(gl_BumpRotMatrix1MESA),
 289    STATEVAR(gl_FogParamsOptimizedMESA),
 290    STATEVAR(gl_CurrentAttribVertMESA),
 291    STATEVAR(gl_CurrentAttribFragMESA),
 292
 293    {NULL, NULL, 0}
 294 };
 295
 296
 297 namespace {
 298
 299 /**
 300  * Data structure that accumulates fields for the gl_PerVertex interface
 301  * block.
 302  */
 303 class per_vertex_accumulator
 304 {
 305 public:
 306    per_vertex_accumulator();
 307    void add_field(int slot, const glsl_type *type, const char *name);
 308    const glsl_type *construct_interface_instance() const;
 309
 310 private:
 311    glsl_struct_field fields[10];
 312    unsigned num_fields;
 313 };
 314
 315
 316 per_vertex_accumulator::per_vertex_accumulator()
 317    : fields(),
 318      num_fields(0)
 319 {
 320 }
 321
 322
 323 void
 324 per_vertex_accumulator::add_field(int slot, const glsl_type *type,
 325                                   const char *name)
 326 {
 327    assert(this->num_fields < ARRAY_SIZE(this->fields));
 328    this->fields[this->num_fields].type = type;
 329    this->fields[this->num_fields].name = name;
 330    this->fields[this->num_fields].row_major = false;
 331    this->fields[this->num_fields].location = slot;
 332    this->fields[this->num_fields].interpolation = INTERP_QUALIFIER_NONE;
 333    this->fields[this->num_fields].centroid = 0;
 334    this->fields[this->num_fields].sample = 0;
 335    this->num_fields++;
 336 }
 337
 338
 339 const glsl_type *
 340 per_vertex_accumulator::construct_interface_instance() const
 341 {
 342    return glsl_type::get_interface_instance(this->fields, this->num_fields,
 343                                             GLSL_INTERFACE_PACKING_STD140,
 344                                             "gl_PerVertex");
 345 }
 346
 347
 348 class builtin_variable_generator
 349 {
 350 public:
 351    builtin_variable_generator(exec_list *instructions,
 352                               struct _mesa_glsl_parse_state *state);
 353    void generate_constants();
 354    void generate_uniforms();
 355    void generate_vs_special_vars();
 356    void generate_gs_special_vars();
 357    void generate_fs_special_vars();
 358    void generate_cs_special_vars();
 359    void generate_varyings();
 360
 361 private:
 362    const glsl_type *array(const glsl_type *base, unsigned elements)
 363    {
 364       return glsl_type::get_array_instance(base, elements);
 365    }
 366
 367    const glsl_type *type(const char *name)
 368    {
 369       return symtab->get_type(name);
 370    }
 371
 372    ir_variable *add_input(int slot, const glsl_type *type, const char *name)
 373    {
 374       return add_variable(name, type, ir_var_shader_in, slot);
 375    }
 376
 377    ir_variable *add_output(int slot, const glsl_type *type, const char *name)
 378    {
 379       return add_variable(name, type, ir_var_shader_out, slot);
 380    }
 381
 382    ir_variable *add_system_value(int slot, const glsl_type *type,
 383                                  const char *name)
 384    {
 385       return add_variable(name, type, ir_var_system_value, slot);
 386    }
 387
 388    ir_variable *add_variable(const char *name, const glsl_type *type,
 389                              enum ir_variable_mode mode, int slot);
 390    ir_variable *add_uniform(const glsl_type *type, const char *name);
 391    ir_variable *add_const(const char *name, int value);
 392    ir_variable *add_const_ivec3(const char *name, int x, int y, int z);
 393    void add_varying(int slot, const glsl_type *type, const char *name,
 394                     const char *name_as_gs_input);
 395
 396    exec_list * const instructions;
 397    struct _mesa_glsl_parse_state * const state;
 398    glsl_symbol_table * const symtab;
 399
 400    /**
 401     * True if compatibility-profile-only variables should be included.  (In
 402     * desktop GL, these are always included when the GLSL version is 1.30 and
 403     * or below).
 404     */
 405    const bool compatibility;
 406
 407    const glsl_type * const bool_t;
 408    const glsl_type * const int_t;
 409    const glsl_type * const float_t;
 410    const glsl_type * const vec2_t;
 411    const glsl_type * const vec3_t;
 412    const glsl_type * const vec4_t;
 413    const glsl_type * const mat3_t;
 414    const glsl_type * const mat4_t;
 415
 416    per_vertex_accumulator per_vertex_in;
 417    per_vertex_accumulator per_vertex_out;
 418 };
 419
 420
 421 builtin_variable_generator::builtin_variable_generator(
 422    exec_list *instructions, struct _mesa_glsl_parse_state *state)
 423    : instructions(instructions), state(state), symtab(state->symbols),
 424      compatibility(!state->is_version(140, 100)),
 425      bool_t(glsl_type::bool_type), int_t(glsl_type::int_type),
 426      float_t(glsl_type::float_type), vec2_t(glsl_type::vec2_type),
 427      vec3_t(glsl_type::vec3_type), vec4_t(glsl_type::vec4_type),
 428      mat3_t(glsl_type::mat3_type), mat4_t(glsl_type::mat4_type)
 429 {
 430 }
 431
 432
 433 ir_variable *
 434 builtin_variable_generator::add_variable(const char *name,
 435                                          const glsl_type *type,
 436                                          enum ir_variable_mode mode, int slot)
 437 {
 438    ir_variable *var = new(symtab) ir_variable(type, name, mode);
 439    var->data.how_declared = ir_var_declared_implicitly;
 440
 441    switch (var->data.mode) {
 442    case ir_var_auto:
 443    case ir_var_shader_in:
 444    case ir_var_uniform:
 445    case ir_var_system_value:
 446       var->data.read_only = true;
 447       break;
 448    case ir_var_shader_out:
 449       break;
 450    default:
 451       /* The only variables that are added using this function should be
 452        * uniforms, shader inputs, and shader outputs, constants (which use
 453        * ir_var_auto), and system values.
 454        */
 455       assert(0);
 456       break;
 457    }
 458
 459    var->data.location = slot;
 460    var->data.explicit_location = (slot >= 0);
 461    var->data.explicit_index = 0;
 462
 463    /* Once the variable is created an initialized, add it to the symbol table
 464     * and add the declaration to the IR stream.
 465     */
 466    instructions->push_tail(var);
 467
 468    symtab->add_variable(var);
 469    return var;
 470 }
 471
 472
 473 ir_variable *
 474 builtin_variable_generator::add_uniform(const glsl_type *type,
 475                                         const char *name)
 476 {
 477    ir_variable *const uni = add_variable(name, type, ir_var_uniform, -1);
 478
 479    unsigned i;
 480    for (i = 0; _mesa_builtin_uniform_desc[i].name != NULL; i++) {
 481       if (strcmp(_mesa_builtin_uniform_desc[i].name, name) == 0) {
 482          break;
 483       }
 484    }
 485
 486    assert(_mesa_builtin_uniform_desc[i].name != NULL);
 487    const struct gl_builtin_uniform_desc* const statevar =
 488       &_mesa_builtin_uniform_desc[i];
 489
 490    const unsigned array_count = type->is_array() ? type->length : 1;
 491    uni->num_state_slots = array_count * statevar->num_elements;
 492
 493    ir_state_slot *slots =
 494       ralloc_array(uni, ir_state_slot, uni->num_state_slots);
 495
 496    uni->state_slots = slots;
 497
 498    for (unsigned a = 0; a < array_count; a++) {
 499       for (unsigned j = 0; j < statevar->num_elements; j++) {
 500          const struct gl_builtin_uniform_element *element =
 501             &statevar->elements[j];
 502
 503          memcpy(slots->tokens, element->tokens, sizeof(element->tokens));
 504          if (type->is_array()) {
 505             if (strcmp(name, "gl_CurrentAttribVertMESA") == 0 ||
 506                 strcmp(name, "gl_CurrentAttribFragMESA") == 0) {
 507                slots->tokens[2] = a;
 508             } else {
 509                slots->tokens[1] = a;
 510             }
 511          }
 512
 513          slots->swizzle = element->swizzle;
 514          slots++;
 515       }
 516    }
 517
 518    return uni;
 519 }
 520
 521
 522 ir_variable *
 523 builtin_variable_generator::add_const(const char *name, int value)
 524 {
 525    ir_variable *const var = add_variable(name, glsl_type::int_type,
 526                                          ir_var_auto, -1);
 527    var->constant_value = new(var) ir_constant(value);
 528    var->constant_initializer = new(var) ir_constant(value);
 529    var->data.has_initializer = true;
 530    return var;
 531 }
 532
 533
 534 ir_variable *
 535 builtin_variable_generator::add_const_ivec3(const char *name, int x, int y,
 536                                             int z)
 537 {
 538    ir_variable *const var = add_variable(name, glsl_type::ivec3_type,
 539                                          ir_var_auto, -1);
 540    ir_constant_data data;
 541    memset(&data, 0, sizeof(data));
 542    data.i[0] = x;
 543    data.i[1] = y;
 544    data.i[2] = z;
 545    var->constant_value = new(var) ir_constant(glsl_type::ivec3_type, &data);
 546    var->constant_initializer =
 547       new(var) ir_constant(glsl_type::ivec3_type, &data);
 548    var->data.has_initializer = true;
 549    return var;
 550 }
 551
 552
 553 void
 554 builtin_variable_generator::generate_constants()
 555 {
 556    add_const("gl_MaxVertexAttribs", state->Const.MaxVertexAttribs);
 557    add_const("gl_MaxVertexTextureImageUnits",
 558              state->Const.MaxVertexTextureImageUnits);
 559    add_const("gl_MaxCombinedTextureImageUnits",
 560              state->Const.MaxCombinedTextureImageUnits);
 561    add_const("gl_MaxTextureImageUnits", state->Const.MaxTextureImageUnits);
 562    add_const("gl_MaxDrawBuffers", state->Const.MaxDrawBuffers);
 563
 564    /* Max uniforms/varyings: GLSL ES counts these in units of vectors; desktop
 565     * GL counts them in units of "components" or "floats".
 566     */
 567    if (state->es_shader) {
 568       add_const("gl_MaxVertexUniformVectors",
 569                 state->Const.MaxVertexUniformComponents / 4);
 570       add_const("gl_MaxFragmentUniformVectors",
 571                 state->Const.MaxFragmentUniformComponents / 4);
 572
 573       /* In GLSL ES 3.00, gl_MaxVaryingVectors was split out to separate
 574        * vertex and fragment shader constants.
 575        */
 576       if (state->is_version(0, 300)) {
 577          add_const("gl_MaxVertexOutputVectors",
 578                    state->ctx->Const.Program[MESA_SHADER_VERTEX].MaxOutputComponents / 4);
 579          add_const("gl_MaxFragmentInputVectors",
 580                    state->ctx->Const.Program[MESA_SHADER_FRAGMENT].MaxInputComponents / 4);
 581       } else {
 582          add_const("gl_MaxVaryingVectors",
 583                    state->ctx->Const.MaxVarying);
 584       }
 585    } else {
 586       add_const("gl_MaxVertexUniformComponents",
 587                 state->Const.MaxVertexUniformComponents);
 588
 589       /* Note: gl_MaxVaryingFloats was deprecated in GLSL 1.30+, but not
 590        * removed
 591        */
 592       add_const("gl_MaxVaryingFloats", state->ctx->Const.MaxVarying * 4);
 593
 594       add_const("gl_MaxFragmentUniformComponents",
 595                 state->Const.MaxFragmentUniformComponents);
 596    }
 597
 598    /* Texel offsets were introduced in ARB_shading_language_420pack (which
 599     * requires desktop GLSL version 130), and adopted into desktop GLSL
 600     * version 4.20 and GLSL ES version 3.00.
 601     */
 602    if ((state->is_version(130, 0) &&
 603         state->ARB_shading_language_420pack_enable) ||
 604       state->is_version(420, 300)) {
 605       add_const("gl_MinProgramTexelOffset",
 606                 state->Const.MinProgramTexelOffset);
 607       add_const("gl_MaxProgramTexelOffset",
 608                 state->Const.MaxProgramTexelOffset);
 609    }
 610
 611    if (state->is_version(130, 0)) {
 612       add_const("gl_MaxClipDistances", state->Const.MaxClipPlanes);
 613       add_const("gl_MaxVaryingComponents", state->ctx->Const.MaxVarying * 4);
 614    }
 615
 616    if (state->is_version(150, 0)) {
 617       add_const("gl_MaxVertexOutputComponents",
 618                 state->Const.MaxVertexOutputComponents);
 619       add_const("gl_MaxGeometryInputComponents",
 620                 state->Const.MaxGeometryInputComponents);
 621       add_const("gl_MaxGeometryOutputComponents",
 622                 state->Const.MaxGeometryOutputComponents);
 623       add_const("gl_MaxFragmentInputComponents",
 624                 state->Const.MaxFragmentInputComponents);
 625       add_const("gl_MaxGeometryTextureImageUnits",
 626                 state->Const.MaxGeometryTextureImageUnits);
 627       add_const("gl_MaxGeometryOutputVertices",
 628                 state->Const.MaxGeometryOutputVertices);
 629       add_const("gl_MaxGeometryTotalOutputComponents",
 630                 state->Const.MaxGeometryTotalOutputComponents);
 631       add_const("gl_MaxGeometryUniformComponents",
 632                 state->Const.MaxGeometryUniformComponents);
 633
 634       /* Note: the GLSL 1.50-4.40 specs require
 635        * gl_MaxGeometryVaryingComponents to be present, and to be at least 64.
 636        * But they do not define what it means (and there does not appear to be
 637        * any corresponding constant in the GL specs).  However,
 638        * ARB_geometry_shader4 defines MAX_GEOMETRY_VARYING_COMPONENTS_ARB to
 639        * be the maximum number of components available for use as geometry
 640        * outputs.  So we assume this is a synonym for
 641        * gl_MaxGeometryOutputComponents.
 642        */
 643       add_const("gl_MaxGeometryVaryingComponents",
 644                 state->Const.MaxGeometryOutputComponents);
 645    }
 646
 647    if (compatibility) {
 648       /* Note: gl_MaxLights stopped being listed as an explicit constant in
 649        * GLSL 1.30, however it continues to be referred to (as a minimum size
 650        * for compatibility-mode uniforms) all the way up through GLSL 4.30, so
 651        * this seems like it was probably an oversight.
 652        */
 653       add_const("gl_MaxLights", state->Const.MaxLights);
 654
 655       add_const("gl_MaxClipPlanes", state->Const.MaxClipPlanes);
 656
 657       /* Note: gl_MaxTextureUnits wasn't made compatibility-only until GLSL
 658        * 1.50, however this seems like it was probably an oversight.
 659        */
 660       add_const("gl_MaxTextureUnits", state->Const.MaxTextureUnits);
 661
 662       /* Note: gl_MaxTextureCoords was left out of GLSL 1.40, but it was
 663        * re-introduced in GLSL 1.50, so this seems like it was probably an
 664        * oversight.
 665        */
 666       add_const("gl_MaxTextureCoords", state->Const.MaxTextureCoords);
 667    }
 668
 669    if (state->ARB_shader_atomic_counters_enable) {
 670       add_const("gl_MaxVertexAtomicCounters",
 671                 state->Const.MaxVertexAtomicCounters);
 672       add_const("gl_MaxGeometryAtomicCounters",
 673                 state->Const.MaxGeometryAtomicCounters);
 674       add_const("gl_MaxFragmentAtomicCounters",
 675                 state->Const.MaxFragmentAtomicCounters);
 676       add_const("gl_MaxCombinedAtomicCounters",
 677                 state->Const.MaxCombinedAtomicCounters);
 678       add_const("gl_MaxAtomicCounterBindings",
 679                 state->Const.MaxAtomicBufferBindings);
 680       add_const("gl_MaxTessControlAtomicCounters", 0);
 681       add_const("gl_MaxTessEvaluationAtomicCounters", 0);
 682    }
 683
 684    if (state->is_version(430, 0) || state->ARB_compute_shader_enable) {
 685       add_const_ivec3("gl_MaxComputeWorkGroupCount",
 686                       state->Const.MaxComputeWorkGroupCount[0],
 687                       state->Const.MaxComputeWorkGroupCount[1],
 688                       state->Const.MaxComputeWorkGroupCount[2]);
 689       add_const_ivec3("gl_MaxComputeWorkGroupSize",
 690                       state->Const.MaxComputeWorkGroupSize[0],
 691                       state->Const.MaxComputeWorkGroupSize[1],
 692                       state->Const.MaxComputeWorkGroupSize[2]);
 693
 694       /* From the GLSL 4.40 spec, section 7.1 (Built-In Language Variables):
 695        *
 696        *     The built-in constant gl_WorkGroupSize is a compute-shader
 697        *     constant containing the local work-group size of the shader.  The
 698        *     size of the work group in the X, Y, and Z dimensions is stored in
 699        *     the x, y, and z components.  The constants values in
 700        *     gl_WorkGroupSize will match those specified in the required
 701        *     local_size_x, local_size_y, and local_size_z layout qualifiers
 702        *     for the current shader.  This is a constant so that it can be
 703        *     used to size arrays of memory that can be shared within the local
 704        *     work group.  It is a compile-time error to use gl_WorkGroupSize
 705        *     in a shader that does not declare a fixed local group size, or
 706        *     before that shader has declared a fixed local group size, using
 707        *     local_size_x, local_size_y, and local_size_z.
 708        *
 709        * To prevent the shader from trying to refer to gl_WorkGroupSize before
 710        * the layout declaration, we don't define it here.  Intead we define it
 711        * in ast_cs_input_layout::hir().
 712        */
 713    }
 714
 715    if (state->is_version(420, 0) ||
 716        state->ARB_shader_image_load_store_enable) {
 717       add_const("gl_MaxImageUnits",
 718                 state->Const.MaxImageUnits);
 719       add_const("gl_MaxCombinedImageUnitsAndFragmentOutputs",
 720                 state->Const.MaxCombinedImageUnitsAndFragmentOutputs);
 721       add_const("gl_MaxImageSamples",
 722                 state->Const.MaxImageSamples);
 723       add_const("gl_MaxVertexImageUniforms",
 724                 state->Const.MaxVertexImageUniforms);
 725       add_const("gl_MaxTessControlImageUniforms", 0);
 726       add_const("gl_MaxTessEvaluationImageUniforms", 0);
 727       add_const("gl_MaxGeometryImageUniforms",
 728                 state->Const.MaxGeometryImageUniforms);
 729       add_const("gl_MaxFragmentImageUniforms",
 730                 state->Const.MaxFragmentImageUniforms);
 731       add_const("gl_MaxCombinedImageUniforms",
 732                 state->Const.MaxCombinedImageUniforms);
 733    }
 734 }
 735
 736
 737 /**
 738  * Generate uniform variables (which exist in all types of shaders).
 739  */
 740 void
 741 builtin_variable_generator::generate_uniforms()
 742 {
 743    add_uniform(int_t, "gl_NumSamples");
 744    add_uniform(type("gl_DepthRangeParameters"), "gl_DepthRange");
 745    add_uniform(array(vec4_t, VERT_ATTRIB_MAX), "gl_CurrentAttribVertMESA");
 746    add_uniform(array(vec4_t, VARYING_SLOT_MAX), "gl_CurrentAttribFragMESA");
 747
 748    if (compatibility) {
 749       add_uniform(mat4_t, "gl_ModelViewMatrix");
 750       add_uniform(mat4_t, "gl_ProjectionMatrix");
 751       add_uniform(mat4_t, "gl_ModelViewProjectionMatrix");
 752       add_uniform(mat3_t, "gl_NormalMatrix");
 753       add_uniform(mat4_t, "gl_ModelViewMatrixInverse");
 754       add_uniform(mat4_t, "gl_ProjectionMatrixInverse");
 755       add_uniform(mat4_t, "gl_ModelViewProjectionMatrixInverse");
 756       add_uniform(mat4_t, "gl_ModelViewMatrixTranspose");
 757       add_uniform(mat4_t, "gl_ProjectionMatrixTranspose");
 758       add_uniform(mat4_t, "gl_ModelViewProjectionMatrixTranspose");
 759       add_uniform(mat4_t, "gl_ModelViewMatrixInverseTranspose");
 760       add_uniform(mat4_t, "gl_ProjectionMatrixInverseTranspose");
 761       add_uniform(mat4_t, "gl_ModelViewProjectionMatrixInverseTranspose");
 762       add_uniform(float_t, "gl_NormalScale");
 763       add_uniform(type("gl_LightModelParameters"), "gl_LightModel");
 764       add_uniform(vec2_t, "gl_BumpRotMatrix0MESA");
 765       add_uniform(vec2_t, "gl_BumpRotMatrix1MESA");
 766       add_uniform(vec4_t, "gl_FogParamsOptimizedMESA");
 767
 768       const glsl_type *const mat4_array_type =
 769          array(mat4_t, state->Const.MaxTextureCoords);
 770       add_uniform(mat4_array_type, "gl_TextureMatrix");
 771       add_uniform(mat4_array_type, "gl_TextureMatrixInverse");
 772       add_uniform(mat4_array_type, "gl_TextureMatrixTranspose");
 773       add_uniform(mat4_array_type, "gl_TextureMatrixInverseTranspose");
 774
 775       add_uniform(array(vec4_t, state->Const.MaxClipPlanes), "gl_ClipPlane");
 776       add_uniform(type("gl_PointParameters"), "gl_Point");
 777
 778       const glsl_type *const material_parameters_type =
 779          type("gl_MaterialParameters");
 780       add_uniform(material_parameters_type, "gl_FrontMaterial");
 781       add_uniform(material_parameters_type, "gl_BackMaterial");
 782
 783       add_uniform(array(type("gl_LightSourceParameters"),
 784                         state->Const.MaxLights),
 785                   "gl_LightSource");
 786
 787       const glsl_type *const light_model_products_type =
 788          type("gl_LightModelProducts");
 789       add_uniform(light_model_products_type, "gl_FrontLightModelProduct");
 790       add_uniform(light_model_products_type, "gl_BackLightModelProduct");
 791
 792       const glsl_type *const light_products_type =
 793          array(type("gl_LightProducts"), state->Const.MaxLights);
 794       add_uniform(light_products_type, "gl_FrontLightProduct");
 795       add_uniform(light_products_type, "gl_BackLightProduct");
 796
 797       add_uniform(array(vec4_t, state->Const.MaxTextureUnits),
 798                   "gl_TextureEnvColor");
 799
 800       const glsl_type *const texcoords_vec4 =
 801          array(vec4_t, state->Const.MaxTextureCoords);
 802       add_uniform(texcoords_vec4, "gl_EyePlaneS");
 803       add_uniform(texcoords_vec4, "gl_EyePlaneT");
 804       add_uniform(texcoords_vec4, "gl_EyePlaneR");
 805       add_uniform(texcoords_vec4, "gl_EyePlaneQ");
 806       add_uniform(texcoords_vec4, "gl_ObjectPlaneS");
 807       add_uniform(texcoords_vec4, "gl_ObjectPlaneT");
 808       add_uniform(texcoords_vec4, "gl_ObjectPlaneR");
 809       add_uniform(texcoords_vec4, "gl_ObjectPlaneQ");
 810
 811       add_uniform(type("gl_FogParameters"), "gl_Fog");
 812    }
 813 }
 814
 815
 816 /**
 817  * Generate variables which only exist in vertex shaders.
 818  */
 819 void
 820 builtin_variable_generator::generate_vs_special_vars()
 821 {
 822    if (state->is_version(130, 300))
 823       add_system_value(SYSTEM_VALUE_VERTEX_ID, int_t, "gl_VertexID");
 824    if (state->ARB_draw_instanced_enable)
 825       add_system_value(SYSTEM_VALUE_INSTANCE_ID, int_t, "gl_InstanceIDARB");
 826    if (state->ARB_draw_instanced_enable || state->is_version(140, 300))
 827       add_system_value(SYSTEM_VALUE_INSTANCE_ID, int_t, "gl_InstanceID");
 828    if (state->AMD_vertex_shader_layer_enable)
 829       add_output(VARYING_SLOT_LAYER, int_t, "gl_Layer");
 830    if (compatibility) {
 831       add_input(VERT_ATTRIB_POS, vec4_t, "gl_Vertex");
 832       add_input(VERT_ATTRIB_NORMAL, vec3_t, "gl_Normal");
 833       add_input(VERT_ATTRIB_COLOR0, vec4_t, "gl_Color");
 834       add_input(VERT_ATTRIB_COLOR1, vec4_t, "gl_SecondaryColor");
 835       add_input(VERT_ATTRIB_TEX0, vec4_t, "gl_MultiTexCoord0");
 836       add_input(VERT_ATTRIB_TEX1, vec4_t, "gl_MultiTexCoord1");
 837       add_input(VERT_ATTRIB_TEX2, vec4_t, "gl_MultiTexCoord2");
 838       add_input(VERT_ATTRIB_TEX3, vec4_t, "gl_MultiTexCoord3");
 839       add_input(VERT_ATTRIB_TEX4, vec4_t, "gl_MultiTexCoord4");
 840       add_input(VERT_ATTRIB_TEX5, vec4_t, "gl_MultiTexCoord5");
 841       add_input(VERT_ATTRIB_TEX6, vec4_t, "gl_MultiTexCoord6");
 842       add_input(VERT_ATTRIB_TEX7, vec4_t, "gl_MultiTexCoord7");
 843       add_input(VERT_ATTRIB_FOG, float_t, "gl_FogCoord");
 844    }
 845 }
 846
 847
 848 /**
 849  * Generate variables which only exist in geometry shaders.
 850  */
 851 void
 852 builtin_variable_generator::generate_gs_special_vars()
 853 {
 854    add_output(VARYING_SLOT_LAYER, int_t, "gl_Layer");
 855    if (state->ARB_viewport_array_enable)
 856       add_output(VARYING_SLOT_VIEWPORT, int_t, "gl_ViewportIndex");
 857    if (state->ARB_gpu_shader5_enable)
 858       add_system_value(SYSTEM_VALUE_INVOCATION_ID, int_t, "gl_InvocationID");
 859
 860    /* Although gl_PrimitiveID appears in tessellation control and tessellation
 861     * evaluation shaders, it has a different function there than it has in
 862     * geometry shaders, so we treat it (and its counterpart gl_PrimitiveIDIn)
 863     * as special geometry shader variables.
 864     *
 865     * Note that although the general convention of suffixing geometry shader
 866     * input varyings with "In" was not adopted into GLSL 1.50, it is used in
 867     * the specific case of gl_PrimitiveIDIn.  So we don't need to treat
 868     * gl_PrimitiveIDIn as an {ARB,EXT}_geometry_shader4-only variable.
 869     */
 870    ir_variable *var;
 871    var = add_input(VARYING_SLOT_PRIMITIVE_ID, int_t, "gl_PrimitiveIDIn");
 872    var->data.interpolation = INTERP_QUALIFIER_FLAT;
 873    var = add_output(VARYING_SLOT_PRIMITIVE_ID, int_t, "gl_PrimitiveID");
 874    var->data.interpolation = INTERP_QUALIFIER_FLAT;
 875 }
 876
 877
 878 /**
 879  * Generate variables which only exist in fragment shaders.
 880  */
 881 void
 882 builtin_variable_generator::generate_fs_special_vars()
 883 {
 884    add_input(VARYING_SLOT_POS, vec4_t, "gl_FragCoord");
 885    add_input(VARYING_SLOT_FACE, bool_t, "gl_FrontFacing");
 886    if (state->is_version(120, 100))
 887       add_input(VARYING_SLOT_PNTC, vec2_t, "gl_PointCoord");
 888
 889    if (state->is_version(150, 0)) {
 890       ir_variable *var =
 891          add_input(VARYING_SLOT_PRIMITIVE_ID, int_t, "gl_PrimitiveID");
 892       var->data.interpolation = INTERP_QUALIFIER_FLAT;
 893    }
 894
 895    /* gl_FragColor and gl_FragData were deprecated starting in desktop GLSL
 896     * 1.30, and were relegated to the compatibility profile in GLSL 4.20.
 897     * They were removed from GLSL ES 3.00.
 898     */
 899    if (compatibility || !state->is_version(420, 300)) {
 900       add_output(FRAG_RESULT_COLOR, vec4_t, "gl_FragColor");
 901       add_output(FRAG_RESULT_DATA0,
 902                  array(vec4_t, state->Const.MaxDrawBuffers), "gl_FragData");
 903    }
 904
 905    /* gl_FragDepth has always been in desktop GLSL, but did not appear in GLSL
 906     * ES 1.00.
 907     */
 908    if (state->is_version(110, 300))
 909       add_output(FRAG_RESULT_DEPTH, float_t, "gl_FragDepth");
 910
 911    if (state->ARB_shader_stencil_export_enable) {
 912       ir_variable *const var =
 913          add_output(FRAG_RESULT_STENCIL, int_t, "gl_FragStencilRefARB");
 914       if (state->ARB_shader_stencil_export_warn)
 915          var->warn_extension = "GL_ARB_shader_stencil_export";
 916    }
 917
 918    if (state->AMD_shader_stencil_export_enable) {
 919       ir_variable *const var =
 920          add_output(FRAG_RESULT_STENCIL, int_t, "gl_FragStencilRefAMD");
 921       if (state->AMD_shader_stencil_export_warn)
 922          var->warn_extension = "GL_AMD_shader_stencil_export";
 923    }
 924
 925    if (state->ARB_sample_shading_enable) {
 926       add_system_value(SYSTEM_VALUE_SAMPLE_ID, int_t, "gl_SampleID");
 927       add_system_value(SYSTEM_VALUE_SAMPLE_POS, vec2_t, "gl_SamplePosition");
 928       /* From the ARB_sample_shading specification:
 929        *    "The number of elements in the array is ceil(<s>/32), where
 930        *    <s> is the maximum number of color samples supported by the
 931        *    implementation."
 932        * Since no drivers expose more than 32x MSAA, we can simply set
 933        * the array size to 1 rather than computing it.
 934        */
 935       add_output(FRAG_RESULT_SAMPLE_MASK, array(int_t, 1), "gl_SampleMask");
 936    }
 937
 938    if (state->ARB_gpu_shader5_enable) {
 939       add_system_value(SYSTEM_VALUE_SAMPLE_MASK_IN, array(int_t, 1), "gl_SampleMaskIn");
 940    }
 941
 942    if (state->ARB_fragment_layer_viewport_enable) {
 943       add_input(VARYING_SLOT_LAYER, int_t, "gl_Layer");
 944       add_input(VARYING_SLOT_VIEWPORT, int_t, "gl_ViewportIndex");
 945    }
 946 }
 947
 948
 949 /**
 950  * Generate variables which only exist in compute shaders.
 951  */
 952 void
 953 builtin_variable_generator::generate_cs_special_vars()
 954 {
 955    /* TODO: finish this. */
 956 }
 957
 958
 959 /**
 960  * Add a single "varying" variable.  The variable's type and direction (input
 961  * or output) are adjusted as appropriate for the type of shader being
 962  * compiled.  For geometry shaders using {ARB,EXT}_geometry_shader4,
 963  * name_as_gs_input is used for the input (to avoid ambiguity).
 964  */
 965 void
 966 builtin_variable_generator::add_varying(int slot, const glsl_type *type,
 967                                         const char *name,
 968                                         const char *name_as_gs_input)
 969 {
 970    switch (state->stage) {
 971    case MESA_SHADER_GEOMETRY:
 972       this->per_vertex_in.add_field(slot, type, name);
 973       /* FALLTHROUGH */
 974    case MESA_SHADER_VERTEX:
 975       this->per_vertex_out.add_field(slot, type, name);
 976       break;
 977    case MESA_SHADER_FRAGMENT:
 978       add_input(slot, type, name);
 979       break;
 980    case MESA_SHADER_COMPUTE:
 981       /* Compute shaders don't have varyings. */
 982       break;
 983    }
 984 }
 985
 986
 987 /**
 988  * Generate variables that are used to communicate data from one shader stage
 989  * to the next ("varyings").
 990  */
 991 void
 992 builtin_variable_generator::generate_varyings()
 993 {
 994 #define ADD_VARYING(loc, type, name) \
 995    add_varying(loc, type, name, name "In")
 996
 997    /* gl_Position and gl_PointSize are not visible from fragment shaders. */
 998    if (state->stage != MESA_SHADER_FRAGMENT) {
 999       ADD_VARYING(VARYING_SLOT_POS, vec4_t, "gl_Position");
1000       ADD_VARYING(VARYING_SLOT_PSIZ, float_t, "gl_PointSize");
1001    }
1002
1003    if (state->is_version(130, 0)) {
1004        ADD_VARYING(VARYING_SLOT_CLIP_DIST0, array(float_t, 0),
1005                    "gl_ClipDistance");
1006    }
1007
1008    if (compatibility) {
1009       ADD_VARYING(VARYING_SLOT_TEX0, array(vec4_t, 0), "gl_TexCoord");
1010       ADD_VARYING(VARYING_SLOT_FOGC, float_t, "gl_FogFragCoord");
1011       if (state->stage == MESA_SHADER_FRAGMENT) {
1012          ADD_VARYING(VARYING_SLOT_COL0, vec4_t, "gl_Color");
1013          ADD_VARYING(VARYING_SLOT_COL1, vec4_t, "gl_SecondaryColor");
1014       } else {
1015          ADD_VARYING(VARYING_SLOT_CLIP_VERTEX, vec4_t, "gl_ClipVertex");
1016          ADD_VARYING(VARYING_SLOT_COL0, vec4_t, "gl_FrontColor");
1017          ADD_VARYING(VARYING_SLOT_BFC0, vec4_t, "gl_BackColor");
1018          ADD_VARYING(VARYING_SLOT_COL1, vec4_t, "gl_FrontSecondaryColor");
1019          ADD_VARYING(VARYING_SLOT_BFC1, vec4_t, "gl_BackSecondaryColor");
1020       }
1021    }
1022
1023    if (state->stage == MESA_SHADER_GEOMETRY) {
1024       const glsl_type *per_vertex_in_type =
1025          this->per_vertex_in.construct_interface_instance();
1026       add_variable("gl_in", array(per_vertex_in_type, 0),
1027                    ir_var_shader_in, -1);
1028    }
1029    if (state->stage == MESA_SHADER_VERTEX || state->stage == MESA_SHADER_GEOMETRY) {
1030       const glsl_type *per_vertex_out_type =
1031          this->per_vertex_out.construct_interface_instance();
1032       const glsl_struct_field *fields = per_vertex_out_type->fields.structure;
1033       for (unsigned i = 0; i < per_vertex_out_type->length; i++) {
1034          ir_variable *var =
1035             add_variable(fields[i].name, fields[i].type, ir_var_shader_out,
1036                          fields[i].location);
1037          var->data.interpolation = fields[i].interpolation;
1038          var->data.centroid = fields[i].centroid;
1039          var->data.sample = fields[i].sample;
1040          var->init_interface_type(per_vertex_out_type);
1041       }
1042    }
1043 }
1044
1045
1046 }; /* Anonymous namespace */
1047
1048
1049 void
1050 _mesa_glsl_initialize_variables(exec_list *instructions,
1051                                 struct _mesa_glsl_parse_state *state)
1052 {
1053    builtin_variable_generator gen(instructions, state);
1054
1055    gen.generate_constants();
1056    gen.generate_uniforms();
1057
1058    gen.generate_varyings();
1059
1060    switch (state->stage) {
1061    case MESA_SHADER_VERTEX:
1062       gen.generate_vs_special_vars();
1063       break;
1064    case MESA_SHADER_GEOMETRY:
1065       gen.generate_gs_special_vars();
1066       break;
1067    case MESA_SHADER_FRAGMENT:
1068       gen.generate_fs_special_vars();
1069       break;
1070    case MESA_SHADER_COMPUTE:
1071       gen.generate_cs_special_vars();
1072       break;
1073    }
1074 }