ast_to_hir.cpp revision 46f7105df487c91569f7e4a8da74d673c12e5619
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/** 25 * \file ast_to_hir.c 26 * Convert abstract syntax to to high-level intermediate reprensentation (HIR). 27 * 28 * During the conversion to HIR, the majority of the symantic checking is 29 * preformed on the program. This includes: 30 * 31 * * Symbol table management 32 * * Type checking 33 * * Function binding 34 * 35 * The majority of this work could be done during parsing, and the parser could 36 * probably generate HIR directly. However, this results in frequent changes 37 * to the parser code. Since we do not assume that every system this complier 38 * is built on will have Flex and Bison installed, we have to store the code 39 * generated by these tools in our version control system. In other parts of 40 * the system we've seen problems where a parser was changed but the generated 41 * code was not committed, merge conflicts where created because two developers 42 * had slightly different versions of Bison installed, etc. 43 * 44 * I have also noticed that running Bison generated parsers in GDB is very 45 * irritating. When you get a segfault on '$$ = $1->foo', you can't very 46 * well 'print $1' in GDB. 47 * 48 * As a result, my preference is to put as little C code as possible in the 49 * parser (and lexer) sources. 50 */ 51 52#include "main/core.h" /* for struct gl_extensions */ 53#include "glsl_symbol_table.h" 54#include "glsl_parser_extras.h" 55#include "ast.h" 56#include "glsl_types.h" 57#include "ir.h" 58 59void 60_mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state) 61{ 62 _mesa_glsl_initialize_variables(instructions, state); 63 _mesa_glsl_initialize_functions(state); 64 65 state->symbols->language_version = state->language_version; 66 67 state->current_function = NULL; 68 69 /* Section 4.2 of the GLSL 1.20 specification states: 70 * "The built-in functions are scoped in a scope outside the global scope 71 * users declare global variables in. That is, a shader's global scope, 72 * available for user-defined functions and global variables, is nested 73 * inside the scope containing the built-in functions." 74 * 75 * Since built-in functions like ftransform() access built-in variables, 76 * it follows that those must be in the outer scope as well. 77 * 78 * We push scope here to create this nesting effect...but don't pop. 79 * This way, a shader's globals are still in the symbol table for use 80 * by the linker. 81 */ 82 state->symbols->push_scope(); 83 84 foreach_list_typed (ast_node, ast, link, & state->translation_unit) 85 ast->hir(instructions, state); 86} 87 88 89/** 90 * If a conversion is available, convert one operand to a different type 91 * 92 * The \c from \c ir_rvalue is converted "in place". 93 * 94 * \param to Type that the operand it to be converted to 95 * \param from Operand that is being converted 96 * \param state GLSL compiler state 97 * 98 * \return 99 * If a conversion is possible (or unnecessary), \c true is returned. 100 * Otherwise \c false is returned. 101 */ 102bool 103apply_implicit_conversion(const glsl_type *to, ir_rvalue * &from, 104 struct _mesa_glsl_parse_state *state) 105{ 106 void *ctx = state; 107 if (to->base_type == from->type->base_type) 108 return true; 109 110 /* This conversion was added in GLSL 1.20. If the compilation mode is 111 * GLSL 1.10, the conversion is skipped. 112 */ 113 if (state->language_version < 120) 114 return false; 115 116 /* From page 27 (page 33 of the PDF) of the GLSL 1.50 spec: 117 * 118 * "There are no implicit array or structure conversions. For 119 * example, an array of int cannot be implicitly converted to an 120 * array of float. There are no implicit conversions between 121 * signed and unsigned integers." 122 */ 123 /* FINISHME: The above comment is partially a lie. There is int/uint 124 * FINISHME: conversion for immediate constants. 125 */ 126 if (!to->is_float() || !from->type->is_numeric()) 127 return false; 128 129 /* Convert to a floating point type with the same number of components 130 * as the original type - i.e. int to float, not int to vec4. 131 */ 132 to = glsl_type::get_instance(GLSL_TYPE_FLOAT, from->type->vector_elements, 133 from->type->matrix_columns); 134 135 switch (from->type->base_type) { 136 case GLSL_TYPE_INT: 137 from = new(ctx) ir_expression(ir_unop_i2f, to, from, NULL); 138 break; 139 case GLSL_TYPE_UINT: 140 from = new(ctx) ir_expression(ir_unop_u2f, to, from, NULL); 141 break; 142 case GLSL_TYPE_BOOL: 143 from = new(ctx) ir_expression(ir_unop_b2f, to, from, NULL); 144 break; 145 default: 146 assert(0); 147 } 148 149 return true; 150} 151 152 153static const struct glsl_type * 154arithmetic_result_type(ir_rvalue * &value_a, ir_rvalue * &value_b, 155 bool multiply, 156 struct _mesa_glsl_parse_state *state, YYLTYPE *loc) 157{ 158 const glsl_type *type_a = value_a->type; 159 const glsl_type *type_b = value_b->type; 160 161 /* From GLSL 1.50 spec, page 56: 162 * 163 * "The arithmetic binary operators add (+), subtract (-), 164 * multiply (*), and divide (/) operate on integer and 165 * floating-point scalars, vectors, and matrices." 166 */ 167 if (!type_a->is_numeric() || !type_b->is_numeric()) { 168 _mesa_glsl_error(loc, state, 169 "Operands to arithmetic operators must be numeric"); 170 return glsl_type::error_type; 171 } 172 173 174 /* "If one operand is floating-point based and the other is 175 * not, then the conversions from Section 4.1.10 "Implicit 176 * Conversions" are applied to the non-floating-point-based operand." 177 */ 178 if (!apply_implicit_conversion(type_a, value_b, state) 179 && !apply_implicit_conversion(type_b, value_a, state)) { 180 _mesa_glsl_error(loc, state, 181 "Could not implicitly convert operands to " 182 "arithmetic operator"); 183 return glsl_type::error_type; 184 } 185 type_a = value_a->type; 186 type_b = value_b->type; 187 188 /* "If the operands are integer types, they must both be signed or 189 * both be unsigned." 190 * 191 * From this rule and the preceeding conversion it can be inferred that 192 * both types must be GLSL_TYPE_FLOAT, or GLSL_TYPE_UINT, or GLSL_TYPE_INT. 193 * The is_numeric check above already filtered out the case where either 194 * type is not one of these, so now the base types need only be tested for 195 * equality. 196 */ 197 if (type_a->base_type != type_b->base_type) { 198 _mesa_glsl_error(loc, state, 199 "base type mismatch for arithmetic operator"); 200 return glsl_type::error_type; 201 } 202 203 /* "All arithmetic binary operators result in the same fundamental type 204 * (signed integer, unsigned integer, or floating-point) as the 205 * operands they operate on, after operand type conversion. After 206 * conversion, the following cases are valid 207 * 208 * * The two operands are scalars. In this case the operation is 209 * applied, resulting in a scalar." 210 */ 211 if (type_a->is_scalar() && type_b->is_scalar()) 212 return type_a; 213 214 /* "* One operand is a scalar, and the other is a vector or matrix. 215 * In this case, the scalar operation is applied independently to each 216 * component of the vector or matrix, resulting in the same size 217 * vector or matrix." 218 */ 219 if (type_a->is_scalar()) { 220 if (!type_b->is_scalar()) 221 return type_b; 222 } else if (type_b->is_scalar()) { 223 return type_a; 224 } 225 226 /* All of the combinations of <scalar, scalar>, <vector, scalar>, 227 * <scalar, vector>, <scalar, matrix>, and <matrix, scalar> have been 228 * handled. 229 */ 230 assert(!type_a->is_scalar()); 231 assert(!type_b->is_scalar()); 232 233 /* "* The two operands are vectors of the same size. In this case, the 234 * operation is done component-wise resulting in the same size 235 * vector." 236 */ 237 if (type_a->is_vector() && type_b->is_vector()) { 238 if (type_a == type_b) { 239 return type_a; 240 } else { 241 _mesa_glsl_error(loc, state, 242 "vector size mismatch for arithmetic operator"); 243 return glsl_type::error_type; 244 } 245 } 246 247 /* All of the combinations of <scalar, scalar>, <vector, scalar>, 248 * <scalar, vector>, <scalar, matrix>, <matrix, scalar>, and 249 * <vector, vector> have been handled. At least one of the operands must 250 * be matrix. Further, since there are no integer matrix types, the base 251 * type of both operands must be float. 252 */ 253 assert(type_a->is_matrix() || type_b->is_matrix()); 254 assert(type_a->base_type == GLSL_TYPE_FLOAT); 255 assert(type_b->base_type == GLSL_TYPE_FLOAT); 256 257 /* "* The operator is add (+), subtract (-), or divide (/), and the 258 * operands are matrices with the same number of rows and the same 259 * number of columns. In this case, the operation is done component- 260 * wise resulting in the same size matrix." 261 * * The operator is multiply (*), where both operands are matrices or 262 * one operand is a vector and the other a matrix. A right vector 263 * operand is treated as a column vector and a left vector operand as a 264 * row vector. In all these cases, it is required that the number of 265 * columns of the left operand is equal to the number of rows of the 266 * right operand. Then, the multiply (*) operation does a linear 267 * algebraic multiply, yielding an object that has the same number of 268 * rows as the left operand and the same number of columns as the right 269 * operand. Section 5.10 "Vector and Matrix Operations" explains in 270 * more detail how vectors and matrices are operated on." 271 */ 272 if (! multiply) { 273 if (type_a == type_b) 274 return type_a; 275 } else { 276 if (type_a->is_matrix() && type_b->is_matrix()) { 277 /* Matrix multiply. The columns of A must match the rows of B. Given 278 * the other previously tested constraints, this means the vector type 279 * of a row from A must be the same as the vector type of a column from 280 * B. 281 */ 282 if (type_a->row_type() == type_b->column_type()) { 283 /* The resulting matrix has the number of columns of matrix B and 284 * the number of rows of matrix A. We get the row count of A by 285 * looking at the size of a vector that makes up a column. The 286 * transpose (size of a row) is done for B. 287 */ 288 const glsl_type *const type = 289 glsl_type::get_instance(type_a->base_type, 290 type_a->column_type()->vector_elements, 291 type_b->row_type()->vector_elements); 292 assert(type != glsl_type::error_type); 293 294 return type; 295 } 296 } else if (type_a->is_matrix()) { 297 /* A is a matrix and B is a column vector. Columns of A must match 298 * rows of B. Given the other previously tested constraints, this 299 * means the vector type of a row from A must be the same as the 300 * vector the type of B. 301 */ 302 if (type_a->row_type() == type_b) { 303 /* The resulting vector has a number of elements equal to 304 * the number of rows of matrix A. */ 305 const glsl_type *const type = 306 glsl_type::get_instance(type_a->base_type, 307 type_a->column_type()->vector_elements, 308 1); 309 assert(type != glsl_type::error_type); 310 311 return type; 312 } 313 } else { 314 assert(type_b->is_matrix()); 315 316 /* A is a row vector and B is a matrix. Columns of A must match rows 317 * of B. Given the other previously tested constraints, this means 318 * the type of A must be the same as the vector type of a column from 319 * B. 320 */ 321 if (type_a == type_b->column_type()) { 322 /* The resulting vector has a number of elements equal to 323 * the number of columns of matrix B. */ 324 const glsl_type *const type = 325 glsl_type::get_instance(type_a->base_type, 326 type_b->row_type()->vector_elements, 327 1); 328 assert(type != glsl_type::error_type); 329 330 return type; 331 } 332 } 333 334 _mesa_glsl_error(loc, state, "size mismatch for matrix multiplication"); 335 return glsl_type::error_type; 336 } 337 338 339 /* "All other cases are illegal." 340 */ 341 _mesa_glsl_error(loc, state, "type mismatch"); 342 return glsl_type::error_type; 343} 344 345 346static const struct glsl_type * 347unary_arithmetic_result_type(const struct glsl_type *type, 348 struct _mesa_glsl_parse_state *state, YYLTYPE *loc) 349{ 350 /* From GLSL 1.50 spec, page 57: 351 * 352 * "The arithmetic unary operators negate (-), post- and pre-increment 353 * and decrement (-- and ++) operate on integer or floating-point 354 * values (including vectors and matrices). All unary operators work 355 * component-wise on their operands. These result with the same type 356 * they operated on." 357 */ 358 if (!type->is_numeric()) { 359 _mesa_glsl_error(loc, state, 360 "Operands to arithmetic operators must be numeric"); 361 return glsl_type::error_type; 362 } 363 364 return type; 365} 366 367/** 368 * \brief Return the result type of a bit-logic operation. 369 * 370 * If the given types to the bit-logic operator are invalid, return 371 * glsl_type::error_type. 372 * 373 * \param type_a Type of LHS of bit-logic op 374 * \param type_b Type of RHS of bit-logic op 375 */ 376static const struct glsl_type * 377bit_logic_result_type(const struct glsl_type *type_a, 378 const struct glsl_type *type_b, 379 ast_operators op, 380 struct _mesa_glsl_parse_state *state, YYLTYPE *loc) 381{ 382 if (state->language_version < 130) { 383 _mesa_glsl_error(loc, state, "bit operations require GLSL 1.30"); 384 return glsl_type::error_type; 385 } 386 387 /* From page 50 (page 56 of PDF) of GLSL 1.30 spec: 388 * 389 * "The bitwise operators and (&), exclusive-or (^), and inclusive-or 390 * (|). The operands must be of type signed or unsigned integers or 391 * integer vectors." 392 */ 393 if (!type_a->is_integer()) { 394 _mesa_glsl_error(loc, state, "LHS of `%s' must be an integer", 395 ast_expression::operator_string(op)); 396 return glsl_type::error_type; 397 } 398 if (!type_b->is_integer()) { 399 _mesa_glsl_error(loc, state, "RHS of `%s' must be an integer", 400 ast_expression::operator_string(op)); 401 return glsl_type::error_type; 402 } 403 404 /* "The fundamental types of the operands (signed or unsigned) must 405 * match," 406 */ 407 if (type_a->base_type != type_b->base_type) { 408 _mesa_glsl_error(loc, state, "operands of `%s' must have the same " 409 "base type", ast_expression::operator_string(op)); 410 return glsl_type::error_type; 411 } 412 413 /* "The operands cannot be vectors of differing size." */ 414 if (type_a->is_vector() && 415 type_b->is_vector() && 416 type_a->vector_elements != type_b->vector_elements) { 417 _mesa_glsl_error(loc, state, "operands of `%s' cannot be vectors of " 418 "different sizes", ast_expression::operator_string(op)); 419 return glsl_type::error_type; 420 } 421 422 /* "If one operand is a scalar and the other a vector, the scalar is 423 * applied component-wise to the vector, resulting in the same type as 424 * the vector. The fundamental types of the operands [...] will be the 425 * resulting fundamental type." 426 */ 427 if (type_a->is_scalar()) 428 return type_b; 429 else 430 return type_a; 431} 432 433static const struct glsl_type * 434modulus_result_type(const struct glsl_type *type_a, 435 const struct glsl_type *type_b, 436 struct _mesa_glsl_parse_state *state, YYLTYPE *loc) 437{ 438 /* From GLSL 1.50 spec, page 56: 439 * "The operator modulus (%) operates on signed or unsigned integers or 440 * integer vectors. The operand types must both be signed or both be 441 * unsigned." 442 */ 443 if (!type_a->is_integer() || !type_b->is_integer() 444 || (type_a->base_type != type_b->base_type)) { 445 _mesa_glsl_error(loc, state, "type mismatch"); 446 return glsl_type::error_type; 447 } 448 449 /* "The operands cannot be vectors of differing size. If one operand is 450 * a scalar and the other vector, then the scalar is applied component- 451 * wise to the vector, resulting in the same type as the vector. If both 452 * are vectors of the same size, the result is computed component-wise." 453 */ 454 if (type_a->is_vector()) { 455 if (!type_b->is_vector() 456 || (type_a->vector_elements == type_b->vector_elements)) 457 return type_a; 458 } else 459 return type_b; 460 461 /* "The operator modulus (%) is not defined for any other data types 462 * (non-integer types)." 463 */ 464 _mesa_glsl_error(loc, state, "type mismatch"); 465 return glsl_type::error_type; 466} 467 468 469static const struct glsl_type * 470relational_result_type(ir_rvalue * &value_a, ir_rvalue * &value_b, 471 struct _mesa_glsl_parse_state *state, YYLTYPE *loc) 472{ 473 const glsl_type *type_a = value_a->type; 474 const glsl_type *type_b = value_b->type; 475 476 /* From GLSL 1.50 spec, page 56: 477 * "The relational operators greater than (>), less than (<), greater 478 * than or equal (>=), and less than or equal (<=) operate only on 479 * scalar integer and scalar floating-point expressions." 480 */ 481 if (!type_a->is_numeric() 482 || !type_b->is_numeric() 483 || !type_a->is_scalar() 484 || !type_b->is_scalar()) { 485 _mesa_glsl_error(loc, state, 486 "Operands to relational operators must be scalar and " 487 "numeric"); 488 return glsl_type::error_type; 489 } 490 491 /* "Either the operands' types must match, or the conversions from 492 * Section 4.1.10 "Implicit Conversions" will be applied to the integer 493 * operand, after which the types must match." 494 */ 495 if (!apply_implicit_conversion(type_a, value_b, state) 496 && !apply_implicit_conversion(type_b, value_a, state)) { 497 _mesa_glsl_error(loc, state, 498 "Could not implicitly convert operands to " 499 "relational operator"); 500 return glsl_type::error_type; 501 } 502 type_a = value_a->type; 503 type_b = value_b->type; 504 505 if (type_a->base_type != type_b->base_type) { 506 _mesa_glsl_error(loc, state, "base type mismatch"); 507 return glsl_type::error_type; 508 } 509 510 /* "The result is scalar Boolean." 511 */ 512 return glsl_type::bool_type; 513} 514 515/** 516 * \brief Return the result type of a bit-shift operation. 517 * 518 * If the given types to the bit-shift operator are invalid, return 519 * glsl_type::error_type. 520 * 521 * \param type_a Type of LHS of bit-shift op 522 * \param type_b Type of RHS of bit-shift op 523 */ 524static const struct glsl_type * 525shift_result_type(const struct glsl_type *type_a, 526 const struct glsl_type *type_b, 527 ast_operators op, 528 struct _mesa_glsl_parse_state *state, YYLTYPE *loc) 529{ 530 if (state->language_version < 130) { 531 _mesa_glsl_error(loc, state, "bit operations require GLSL 1.30"); 532 return glsl_type::error_type; 533 } 534 535 /* From page 50 (page 56 of the PDF) of the GLSL 1.30 spec: 536 * 537 * "The shift operators (<<) and (>>). For both operators, the operands 538 * must be signed or unsigned integers or integer vectors. One operand 539 * can be signed while the other is unsigned." 540 */ 541 if (!type_a->is_integer()) { 542 _mesa_glsl_error(loc, state, "LHS of operator %s must be an integer or " 543 "integer vector", ast_expression::operator_string(op)); 544 return glsl_type::error_type; 545 546 } 547 if (!type_b->is_integer()) { 548 _mesa_glsl_error(loc, state, "RHS of operator %s must be an integer or " 549 "integer vector", ast_expression::operator_string(op)); 550 return glsl_type::error_type; 551 } 552 553 /* "If the first operand is a scalar, the second operand has to be 554 * a scalar as well." 555 */ 556 if (type_a->is_scalar() && !type_b->is_scalar()) { 557 _mesa_glsl_error(loc, state, "If the first operand of %s is scalar, the " 558 "second must be scalar as well", 559 ast_expression::operator_string(op)); 560 return glsl_type::error_type; 561 } 562 563 /* If both operands are vectors, check that they have same number of 564 * elements. 565 */ 566 if (type_a->is_vector() && 567 type_b->is_vector() && 568 type_a->vector_elements != type_b->vector_elements) { 569 _mesa_glsl_error(loc, state, "Vector operands to operator %s must " 570 "have same number of elements", 571 ast_expression::operator_string(op)); 572 return glsl_type::error_type; 573 } 574 575 /* "In all cases, the resulting type will be the same type as the left 576 * operand." 577 */ 578 return type_a; 579} 580 581/** 582 * Validates that a value can be assigned to a location with a specified type 583 * 584 * Validates that \c rhs can be assigned to some location. If the types are 585 * not an exact match but an automatic conversion is possible, \c rhs will be 586 * converted. 587 * 588 * \return 589 * \c NULL if \c rhs cannot be assigned to a location with type \c lhs_type. 590 * Otherwise the actual RHS to be assigned will be returned. This may be 591 * \c rhs, or it may be \c rhs after some type conversion. 592 * 593 * \note 594 * In addition to being used for assignments, this function is used to 595 * type-check return values. 596 */ 597ir_rvalue * 598validate_assignment(struct _mesa_glsl_parse_state *state, 599 const glsl_type *lhs_type, ir_rvalue *rhs) 600{ 601 /* If there is already some error in the RHS, just return it. Anything 602 * else will lead to an avalanche of error message back to the user. 603 */ 604 if (rhs->type->is_error()) 605 return rhs; 606 607 /* If the types are identical, the assignment can trivially proceed. 608 */ 609 if (rhs->type == lhs_type) 610 return rhs; 611 612 /* If the array element types are the same and the size of the LHS is zero, 613 * the assignment is okay. 614 * 615 * Note: Whole-array assignments are not permitted in GLSL 1.10, but this 616 * is handled by ir_dereference::is_lvalue. 617 */ 618 if (lhs_type->is_array() && rhs->type->is_array() 619 && (lhs_type->element_type() == rhs->type->element_type()) 620 && (lhs_type->array_size() == 0)) { 621 return rhs; 622 } 623 624 /* Check for implicit conversion in GLSL 1.20 */ 625 if (apply_implicit_conversion(lhs_type, rhs, state)) { 626 if (rhs->type == lhs_type) 627 return rhs; 628 } 629 630 return NULL; 631} 632 633ir_rvalue * 634do_assignment(exec_list *instructions, struct _mesa_glsl_parse_state *state, 635 ir_rvalue *lhs, ir_rvalue *rhs, 636 YYLTYPE lhs_loc) 637{ 638 void *ctx = state; 639 bool error_emitted = (lhs->type->is_error() || rhs->type->is_error()); 640 641 if (!error_emitted) { 642 if (!lhs->is_lvalue()) { 643 _mesa_glsl_error(& lhs_loc, state, "non-lvalue in assignment"); 644 error_emitted = true; 645 } 646 647 if (state->es_shader && lhs->type->is_array()) { 648 _mesa_glsl_error(&lhs_loc, state, "whole array assignment is not " 649 "allowed in GLSL ES 1.00."); 650 error_emitted = true; 651 } 652 } 653 654 ir_rvalue *new_rhs = validate_assignment(state, lhs->type, rhs); 655 if (new_rhs == NULL) { 656 _mesa_glsl_error(& lhs_loc, state, "type mismatch"); 657 } else { 658 rhs = new_rhs; 659 660 /* If the LHS array was not declared with a size, it takes it size from 661 * the RHS. If the LHS is an l-value and a whole array, it must be a 662 * dereference of a variable. Any other case would require that the LHS 663 * is either not an l-value or not a whole array. 664 */ 665 if (lhs->type->array_size() == 0) { 666 ir_dereference *const d = lhs->as_dereference(); 667 668 assert(d != NULL); 669 670 ir_variable *const var = d->variable_referenced(); 671 672 assert(var != NULL); 673 674 if (var->max_array_access >= unsigned(rhs->type->array_size())) { 675 /* FINISHME: This should actually log the location of the RHS. */ 676 _mesa_glsl_error(& lhs_loc, state, "array size must be > %u due to " 677 "previous access", 678 var->max_array_access); 679 } 680 681 var->type = glsl_type::get_array_instance(lhs->type->element_type(), 682 rhs->type->array_size()); 683 d->type = var->type; 684 } 685 } 686 687 /* Most callers of do_assignment (assign, add_assign, pre_inc/dec, 688 * but not post_inc) need the converted assigned value as an rvalue 689 * to handle things like: 690 * 691 * i = j += 1; 692 * 693 * So we always just store the computed value being assigned to a 694 * temporary and return a deref of that temporary. If the rvalue 695 * ends up not being used, the temp will get copy-propagated out. 696 */ 697 ir_variable *var = new(ctx) ir_variable(rhs->type, "assignment_tmp", 698 ir_var_temporary); 699 ir_dereference_variable *deref_var = new(ctx) ir_dereference_variable(var); 700 instructions->push_tail(var); 701 instructions->push_tail(new(ctx) ir_assignment(deref_var, 702 rhs, 703 NULL)); 704 deref_var = new(ctx) ir_dereference_variable(var); 705 706 if (!error_emitted) 707 instructions->push_tail(new(ctx) ir_assignment(lhs, deref_var, NULL)); 708 709 return new(ctx) ir_dereference_variable(var); 710} 711 712static ir_rvalue * 713get_lvalue_copy(exec_list *instructions, ir_rvalue *lvalue) 714{ 715 void *ctx = talloc_parent(lvalue); 716 ir_variable *var; 717 718 var = new(ctx) ir_variable(lvalue->type, "_post_incdec_tmp", 719 ir_var_temporary); 720 instructions->push_tail(var); 721 var->mode = ir_var_auto; 722 723 instructions->push_tail(new(ctx) ir_assignment(new(ctx) ir_dereference_variable(var), 724 lvalue, NULL)); 725 726 /* Once we've created this temporary, mark it read only so it's no 727 * longer considered an lvalue. 728 */ 729 var->read_only = true; 730 731 return new(ctx) ir_dereference_variable(var); 732} 733 734 735ir_rvalue * 736ast_node::hir(exec_list *instructions, 737 struct _mesa_glsl_parse_state *state) 738{ 739 (void) instructions; 740 (void) state; 741 742 return NULL; 743} 744 745static void 746mark_whole_array_access(ir_rvalue *access) 747{ 748 ir_dereference_variable *deref = access->as_dereference_variable(); 749 750 if (deref) { 751 deref->var->max_array_access = deref->type->length - 1; 752 } 753} 754 755static ir_rvalue * 756do_comparison(void *mem_ctx, int operation, ir_rvalue *op0, ir_rvalue *op1) 757{ 758 int join_op; 759 ir_rvalue *cmp = NULL; 760 761 if (operation == ir_binop_all_equal) 762 join_op = ir_binop_logic_and; 763 else 764 join_op = ir_binop_logic_or; 765 766 switch (op0->type->base_type) { 767 case GLSL_TYPE_FLOAT: 768 case GLSL_TYPE_UINT: 769 case GLSL_TYPE_INT: 770 case GLSL_TYPE_BOOL: 771 return new(mem_ctx) ir_expression(operation, op0, op1); 772 773 case GLSL_TYPE_ARRAY: { 774 for (unsigned int i = 0; i < op0->type->length; i++) { 775 ir_rvalue *e0, *e1, *result; 776 777 e0 = new(mem_ctx) ir_dereference_array(op0->clone(mem_ctx, NULL), 778 new(mem_ctx) ir_constant(i)); 779 e1 = new(mem_ctx) ir_dereference_array(op1->clone(mem_ctx, NULL), 780 new(mem_ctx) ir_constant(i)); 781 result = do_comparison(mem_ctx, operation, e0, e1); 782 783 if (cmp) { 784 cmp = new(mem_ctx) ir_expression(join_op, cmp, result); 785 } else { 786 cmp = result; 787 } 788 } 789 790 mark_whole_array_access(op0); 791 mark_whole_array_access(op1); 792 break; 793 } 794 795 case GLSL_TYPE_STRUCT: { 796 for (unsigned int i = 0; i < op0->type->length; i++) { 797 ir_rvalue *e0, *e1, *result; 798 const char *field_name = op0->type->fields.structure[i].name; 799 800 e0 = new(mem_ctx) ir_dereference_record(op0->clone(mem_ctx, NULL), 801 field_name); 802 e1 = new(mem_ctx) ir_dereference_record(op1->clone(mem_ctx, NULL), 803 field_name); 804 result = do_comparison(mem_ctx, operation, e0, e1); 805 806 if (cmp) { 807 cmp = new(mem_ctx) ir_expression(join_op, cmp, result); 808 } else { 809 cmp = result; 810 } 811 } 812 break; 813 } 814 815 case GLSL_TYPE_ERROR: 816 case GLSL_TYPE_VOID: 817 case GLSL_TYPE_SAMPLER: 818 /* I assume a comparison of a struct containing a sampler just 819 * ignores the sampler present in the type. 820 */ 821 break; 822 823 default: 824 assert(!"Should not get here."); 825 break; 826 } 827 828 if (cmp == NULL) 829 cmp = new(mem_ctx) ir_constant(true); 830 831 return cmp; 832} 833 834ir_rvalue * 835ast_expression::hir(exec_list *instructions, 836 struct _mesa_glsl_parse_state *state) 837{ 838 void *ctx = state; 839 static const int operations[AST_NUM_OPERATORS] = { 840 -1, /* ast_assign doesn't convert to ir_expression. */ 841 -1, /* ast_plus doesn't convert to ir_expression. */ 842 ir_unop_neg, 843 ir_binop_add, 844 ir_binop_sub, 845 ir_binop_mul, 846 ir_binop_div, 847 ir_binop_mod, 848 ir_binop_lshift, 849 ir_binop_rshift, 850 ir_binop_less, 851 ir_binop_greater, 852 ir_binop_lequal, 853 ir_binop_gequal, 854 ir_binop_all_equal, 855 ir_binop_any_nequal, 856 ir_binop_bit_and, 857 ir_binop_bit_xor, 858 ir_binop_bit_or, 859 ir_unop_bit_not, 860 ir_binop_logic_and, 861 ir_binop_logic_xor, 862 ir_binop_logic_or, 863 ir_unop_logic_not, 864 865 /* Note: The following block of expression types actually convert 866 * to multiple IR instructions. 867 */ 868 ir_binop_mul, /* ast_mul_assign */ 869 ir_binop_div, /* ast_div_assign */ 870 ir_binop_mod, /* ast_mod_assign */ 871 ir_binop_add, /* ast_add_assign */ 872 ir_binop_sub, /* ast_sub_assign */ 873 ir_binop_lshift, /* ast_ls_assign */ 874 ir_binop_rshift, /* ast_rs_assign */ 875 ir_binop_bit_and, /* ast_and_assign */ 876 ir_binop_bit_xor, /* ast_xor_assign */ 877 ir_binop_bit_or, /* ast_or_assign */ 878 879 -1, /* ast_conditional doesn't convert to ir_expression. */ 880 ir_binop_add, /* ast_pre_inc. */ 881 ir_binop_sub, /* ast_pre_dec. */ 882 ir_binop_add, /* ast_post_inc. */ 883 ir_binop_sub, /* ast_post_dec. */ 884 -1, /* ast_field_selection doesn't conv to ir_expression. */ 885 -1, /* ast_array_index doesn't convert to ir_expression. */ 886 -1, /* ast_function_call doesn't conv to ir_expression. */ 887 -1, /* ast_identifier doesn't convert to ir_expression. */ 888 -1, /* ast_int_constant doesn't convert to ir_expression. */ 889 -1, /* ast_uint_constant doesn't conv to ir_expression. */ 890 -1, /* ast_float_constant doesn't conv to ir_expression. */ 891 -1, /* ast_bool_constant doesn't conv to ir_expression. */ 892 -1, /* ast_sequence doesn't convert to ir_expression. */ 893 }; 894 ir_rvalue *result = NULL; 895 ir_rvalue *op[3]; 896 const struct glsl_type *type = glsl_type::error_type; 897 bool error_emitted = false; 898 YYLTYPE loc; 899 900 loc = this->get_location(); 901 902 switch (this->oper) { 903 case ast_assign: { 904 op[0] = this->subexpressions[0]->hir(instructions, state); 905 op[1] = this->subexpressions[1]->hir(instructions, state); 906 907 result = do_assignment(instructions, state, op[0], op[1], 908 this->subexpressions[0]->get_location()); 909 error_emitted = result->type->is_error(); 910 type = result->type; 911 break; 912 } 913 914 case ast_plus: 915 op[0] = this->subexpressions[0]->hir(instructions, state); 916 917 type = unary_arithmetic_result_type(op[0]->type, state, & loc); 918 919 error_emitted = type->is_error(); 920 921 result = op[0]; 922 break; 923 924 case ast_neg: 925 op[0] = this->subexpressions[0]->hir(instructions, state); 926 927 type = unary_arithmetic_result_type(op[0]->type, state, & loc); 928 929 error_emitted = type->is_error(); 930 931 result = new(ctx) ir_expression(operations[this->oper], type, 932 op[0], NULL); 933 break; 934 935 case ast_add: 936 case ast_sub: 937 case ast_mul: 938 case ast_div: 939 op[0] = this->subexpressions[0]->hir(instructions, state); 940 op[1] = this->subexpressions[1]->hir(instructions, state); 941 942 type = arithmetic_result_type(op[0], op[1], 943 (this->oper == ast_mul), 944 state, & loc); 945 error_emitted = type->is_error(); 946 947 result = new(ctx) ir_expression(operations[this->oper], type, 948 op[0], op[1]); 949 break; 950 951 case ast_mod: 952 op[0] = this->subexpressions[0]->hir(instructions, state); 953 op[1] = this->subexpressions[1]->hir(instructions, state); 954 955 type = modulus_result_type(op[0]->type, op[1]->type, state, & loc); 956 957 assert(operations[this->oper] == ir_binop_mod); 958 959 result = new(ctx) ir_expression(operations[this->oper], type, 960 op[0], op[1]); 961 error_emitted = type->is_error(); 962 break; 963 964 case ast_lshift: 965 case ast_rshift: 966 if (state->language_version < 130) { 967 _mesa_glsl_error(&loc, state, "operator %s requires GLSL 1.30", 968 operator_string(this->oper)); 969 error_emitted = true; 970 } 971 972 op[0] = this->subexpressions[0]->hir(instructions, state); 973 op[1] = this->subexpressions[1]->hir(instructions, state); 974 type = shift_result_type(op[0]->type, op[1]->type, this->oper, state, 975 &loc); 976 result = new(ctx) ir_expression(operations[this->oper], type, 977 op[0], op[1]); 978 error_emitted = op[0]->type->is_error() || op[1]->type->is_error(); 979 break; 980 981 case ast_less: 982 case ast_greater: 983 case ast_lequal: 984 case ast_gequal: 985 op[0] = this->subexpressions[0]->hir(instructions, state); 986 op[1] = this->subexpressions[1]->hir(instructions, state); 987 988 type = relational_result_type(op[0], op[1], state, & loc); 989 990 /* The relational operators must either generate an error or result 991 * in a scalar boolean. See page 57 of the GLSL 1.50 spec. 992 */ 993 assert(type->is_error() 994 || ((type->base_type == GLSL_TYPE_BOOL) 995 && type->is_scalar())); 996 997 result = new(ctx) ir_expression(operations[this->oper], type, 998 op[0], op[1]); 999 error_emitted = type->is_error(); 1000 break; 1001 1002 case ast_nequal: 1003 case ast_equal: 1004 op[0] = this->subexpressions[0]->hir(instructions, state); 1005 op[1] = this->subexpressions[1]->hir(instructions, state); 1006 1007 /* From page 58 (page 64 of the PDF) of the GLSL 1.50 spec: 1008 * 1009 * "The equality operators equal (==), and not equal (!=) 1010 * operate on all types. They result in a scalar Boolean. If 1011 * the operand types do not match, then there must be a 1012 * conversion from Section 4.1.10 "Implicit Conversions" 1013 * applied to one operand that can make them match, in which 1014 * case this conversion is done." 1015 */ 1016 if ((!apply_implicit_conversion(op[0]->type, op[1], state) 1017 && !apply_implicit_conversion(op[1]->type, op[0], state)) 1018 || (op[0]->type != op[1]->type)) { 1019 _mesa_glsl_error(& loc, state, "operands of `%s' must have the same " 1020 "type", (this->oper == ast_equal) ? "==" : "!="); 1021 error_emitted = true; 1022 } else if ((state->language_version <= 110) 1023 && (op[0]->type->is_array() || op[1]->type->is_array())) { 1024 _mesa_glsl_error(& loc, state, "array comparisons forbidden in " 1025 "GLSL 1.10"); 1026 error_emitted = true; 1027 } 1028 1029 result = do_comparison(ctx, operations[this->oper], op[0], op[1]); 1030 type = glsl_type::bool_type; 1031 1032 assert(error_emitted || (result->type == glsl_type::bool_type)); 1033 break; 1034 1035 case ast_bit_and: 1036 case ast_bit_xor: 1037 case ast_bit_or: 1038 op[0] = this->subexpressions[0]->hir(instructions, state); 1039 op[1] = this->subexpressions[1]->hir(instructions, state); 1040 type = bit_logic_result_type(op[0]->type, op[1]->type, this->oper, 1041 state, &loc); 1042 result = new(ctx) ir_expression(operations[this->oper], type, 1043 op[0], op[1]); 1044 error_emitted = op[0]->type->is_error() || op[1]->type->is_error(); 1045 break; 1046 1047 case ast_bit_not: 1048 op[0] = this->subexpressions[0]->hir(instructions, state); 1049 1050 if (state->language_version < 130) { 1051 _mesa_glsl_error(&loc, state, "bit-wise operations require GLSL 1.30"); 1052 error_emitted = true; 1053 } 1054 1055 if (!op[0]->type->is_integer()) { 1056 _mesa_glsl_error(&loc, state, "operand of `~' must be an integer"); 1057 error_emitted = true; 1058 } 1059 1060 type = op[0]->type; 1061 result = new(ctx) ir_expression(ir_unop_bit_not, type, op[0], NULL); 1062 break; 1063 1064 case ast_logic_and: { 1065 op[0] = this->subexpressions[0]->hir(instructions, state); 1066 1067 if (!op[0]->type->is_boolean() || !op[0]->type->is_scalar()) { 1068 YYLTYPE loc = this->subexpressions[0]->get_location(); 1069 1070 _mesa_glsl_error(& loc, state, "LHS of `%s' must be scalar boolean", 1071 operator_string(this->oper)); 1072 error_emitted = true; 1073 } 1074 1075 ir_constant *op0_const = op[0]->constant_expression_value(); 1076 if (op0_const) { 1077 if (op0_const->value.b[0]) { 1078 op[1] = this->subexpressions[1]->hir(instructions, state); 1079 1080 if (!op[1]->type->is_boolean() || !op[1]->type->is_scalar()) { 1081 YYLTYPE loc = this->subexpressions[1]->get_location(); 1082 1083 _mesa_glsl_error(& loc, state, 1084 "RHS of `%s' must be scalar boolean", 1085 operator_string(this->oper)); 1086 error_emitted = true; 1087 } 1088 result = op[1]; 1089 } else { 1090 result = op0_const; 1091 } 1092 type = glsl_type::bool_type; 1093 } else { 1094 ir_variable *const tmp = new(ctx) ir_variable(glsl_type::bool_type, 1095 "and_tmp", 1096 ir_var_temporary); 1097 instructions->push_tail(tmp); 1098 1099 ir_if *const stmt = new(ctx) ir_if(op[0]); 1100 instructions->push_tail(stmt); 1101 1102 op[1] = this->subexpressions[1]->hir(&stmt->then_instructions, state); 1103 1104 if (!op[1]->type->is_boolean() || !op[1]->type->is_scalar()) { 1105 YYLTYPE loc = this->subexpressions[1]->get_location(); 1106 1107 _mesa_glsl_error(& loc, state, 1108 "RHS of `%s' must be scalar boolean", 1109 operator_string(this->oper)); 1110 error_emitted = true; 1111 } 1112 1113 ir_dereference *const then_deref = new(ctx) ir_dereference_variable(tmp); 1114 ir_assignment *const then_assign = 1115 new(ctx) ir_assignment(then_deref, op[1], NULL); 1116 stmt->then_instructions.push_tail(then_assign); 1117 1118 ir_dereference *const else_deref = new(ctx) ir_dereference_variable(tmp); 1119 ir_assignment *const else_assign = 1120 new(ctx) ir_assignment(else_deref, new(ctx) ir_constant(false), NULL); 1121 stmt->else_instructions.push_tail(else_assign); 1122 1123 result = new(ctx) ir_dereference_variable(tmp); 1124 type = tmp->type; 1125 } 1126 break; 1127 } 1128 1129 case ast_logic_or: { 1130 op[0] = this->subexpressions[0]->hir(instructions, state); 1131 1132 if (!op[0]->type->is_boolean() || !op[0]->type->is_scalar()) { 1133 YYLTYPE loc = this->subexpressions[0]->get_location(); 1134 1135 _mesa_glsl_error(& loc, state, "LHS of `%s' must be scalar boolean", 1136 operator_string(this->oper)); 1137 error_emitted = true; 1138 } 1139 1140 ir_constant *op0_const = op[0]->constant_expression_value(); 1141 if (op0_const) { 1142 if (op0_const->value.b[0]) { 1143 result = op0_const; 1144 } else { 1145 op[1] = this->subexpressions[1]->hir(instructions, state); 1146 1147 if (!op[1]->type->is_boolean() || !op[1]->type->is_scalar()) { 1148 YYLTYPE loc = this->subexpressions[1]->get_location(); 1149 1150 _mesa_glsl_error(& loc, state, 1151 "RHS of `%s' must be scalar boolean", 1152 operator_string(this->oper)); 1153 error_emitted = true; 1154 } 1155 result = op[1]; 1156 } 1157 type = glsl_type::bool_type; 1158 } else { 1159 ir_variable *const tmp = new(ctx) ir_variable(glsl_type::bool_type, 1160 "or_tmp", 1161 ir_var_temporary); 1162 instructions->push_tail(tmp); 1163 1164 ir_if *const stmt = new(ctx) ir_if(op[0]); 1165 instructions->push_tail(stmt); 1166 1167 op[1] = this->subexpressions[1]->hir(&stmt->else_instructions, state); 1168 1169 if (!op[1]->type->is_boolean() || !op[1]->type->is_scalar()) { 1170 YYLTYPE loc = this->subexpressions[1]->get_location(); 1171 1172 _mesa_glsl_error(& loc, state, "RHS of `%s' must be scalar boolean", 1173 operator_string(this->oper)); 1174 error_emitted = true; 1175 } 1176 1177 ir_dereference *const then_deref = new(ctx) ir_dereference_variable(tmp); 1178 ir_assignment *const then_assign = 1179 new(ctx) ir_assignment(then_deref, new(ctx) ir_constant(true), NULL); 1180 stmt->then_instructions.push_tail(then_assign); 1181 1182 ir_dereference *const else_deref = new(ctx) ir_dereference_variable(tmp); 1183 ir_assignment *const else_assign = 1184 new(ctx) ir_assignment(else_deref, op[1], NULL); 1185 stmt->else_instructions.push_tail(else_assign); 1186 1187 result = new(ctx) ir_dereference_variable(tmp); 1188 type = tmp->type; 1189 } 1190 break; 1191 } 1192 1193 case ast_logic_xor: 1194 op[0] = this->subexpressions[0]->hir(instructions, state); 1195 op[1] = this->subexpressions[1]->hir(instructions, state); 1196 1197 1198 result = new(ctx) ir_expression(operations[this->oper], glsl_type::bool_type, 1199 op[0], op[1]); 1200 type = glsl_type::bool_type; 1201 break; 1202 1203 case ast_logic_not: 1204 op[0] = this->subexpressions[0]->hir(instructions, state); 1205 1206 if (!op[0]->type->is_boolean() || !op[0]->type->is_scalar()) { 1207 YYLTYPE loc = this->subexpressions[0]->get_location(); 1208 1209 _mesa_glsl_error(& loc, state, 1210 "operand of `!' must be scalar boolean"); 1211 error_emitted = true; 1212 } 1213 1214 result = new(ctx) ir_expression(operations[this->oper], glsl_type::bool_type, 1215 op[0], NULL); 1216 type = glsl_type::bool_type; 1217 break; 1218 1219 case ast_mul_assign: 1220 case ast_div_assign: 1221 case ast_add_assign: 1222 case ast_sub_assign: { 1223 op[0] = this->subexpressions[0]->hir(instructions, state); 1224 op[1] = this->subexpressions[1]->hir(instructions, state); 1225 1226 type = arithmetic_result_type(op[0], op[1], 1227 (this->oper == ast_mul_assign), 1228 state, & loc); 1229 1230 ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper], type, 1231 op[0], op[1]); 1232 1233 result = do_assignment(instructions, state, 1234 op[0]->clone(ctx, NULL), temp_rhs, 1235 this->subexpressions[0]->get_location()); 1236 type = result->type; 1237 error_emitted = (op[0]->type->is_error()); 1238 1239 /* GLSL 1.10 does not allow array assignment. However, we don't have to 1240 * explicitly test for this because none of the binary expression 1241 * operators allow array operands either. 1242 */ 1243 1244 break; 1245 } 1246 1247 case ast_mod_assign: { 1248 op[0] = this->subexpressions[0]->hir(instructions, state); 1249 op[1] = this->subexpressions[1]->hir(instructions, state); 1250 1251 type = modulus_result_type(op[0]->type, op[1]->type, state, & loc); 1252 1253 assert(operations[this->oper] == ir_binop_mod); 1254 1255 ir_rvalue *temp_rhs; 1256 temp_rhs = new(ctx) ir_expression(operations[this->oper], type, 1257 op[0], op[1]); 1258 1259 result = do_assignment(instructions, state, 1260 op[0]->clone(ctx, NULL), temp_rhs, 1261 this->subexpressions[0]->get_location()); 1262 type = result->type; 1263 error_emitted = type->is_error(); 1264 break; 1265 } 1266 1267 case ast_ls_assign: 1268 case ast_rs_assign: { 1269 op[0] = this->subexpressions[0]->hir(instructions, state); 1270 op[1] = this->subexpressions[1]->hir(instructions, state); 1271 type = shift_result_type(op[0]->type, op[1]->type, this->oper, state, 1272 &loc); 1273 ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper], 1274 type, op[0], op[1]); 1275 result = do_assignment(instructions, state, op[0]->clone(ctx, NULL), 1276 temp_rhs, 1277 this->subexpressions[0]->get_location()); 1278 error_emitted = op[0]->type->is_error() || op[1]->type->is_error(); 1279 break; 1280 } 1281 1282 case ast_and_assign: 1283 case ast_xor_assign: 1284 case ast_or_assign: { 1285 op[0] = this->subexpressions[0]->hir(instructions, state); 1286 op[1] = this->subexpressions[1]->hir(instructions, state); 1287 type = bit_logic_result_type(op[0]->type, op[1]->type, this->oper, 1288 state, &loc); 1289 ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper], 1290 type, op[0], op[1]); 1291 result = do_assignment(instructions, state, op[0]->clone(ctx, NULL), 1292 temp_rhs, 1293 this->subexpressions[0]->get_location()); 1294 error_emitted = op[0]->type->is_error() || op[1]->type->is_error(); 1295 break; 1296 } 1297 1298 case ast_conditional: { 1299 op[0] = this->subexpressions[0]->hir(instructions, state); 1300 1301 /* From page 59 (page 65 of the PDF) of the GLSL 1.50 spec: 1302 * 1303 * "The ternary selection operator (?:). It operates on three 1304 * expressions (exp1 ? exp2 : exp3). This operator evaluates the 1305 * first expression, which must result in a scalar Boolean." 1306 */ 1307 if (!op[0]->type->is_boolean() || !op[0]->type->is_scalar()) { 1308 YYLTYPE loc = this->subexpressions[0]->get_location(); 1309 1310 _mesa_glsl_error(& loc, state, "?: condition must be scalar boolean"); 1311 error_emitted = true; 1312 } 1313 1314 /* The :? operator is implemented by generating an anonymous temporary 1315 * followed by an if-statement. The last instruction in each branch of 1316 * the if-statement assigns a value to the anonymous temporary. This 1317 * temporary is the r-value of the expression. 1318 */ 1319 exec_list then_instructions; 1320 exec_list else_instructions; 1321 1322 op[1] = this->subexpressions[1]->hir(&then_instructions, state); 1323 op[2] = this->subexpressions[2]->hir(&else_instructions, state); 1324 1325 /* From page 59 (page 65 of the PDF) of the GLSL 1.50 spec: 1326 * 1327 * "The second and third expressions can be any type, as 1328 * long their types match, or there is a conversion in 1329 * Section 4.1.10 "Implicit Conversions" that can be applied 1330 * to one of the expressions to make their types match. This 1331 * resulting matching type is the type of the entire 1332 * expression." 1333 */ 1334 if ((!apply_implicit_conversion(op[1]->type, op[2], state) 1335 && !apply_implicit_conversion(op[2]->type, op[1], state)) 1336 || (op[1]->type != op[2]->type)) { 1337 YYLTYPE loc = this->subexpressions[1]->get_location(); 1338 1339 _mesa_glsl_error(& loc, state, "Second and third operands of ?: " 1340 "operator must have matching types."); 1341 error_emitted = true; 1342 type = glsl_type::error_type; 1343 } else { 1344 type = op[1]->type; 1345 } 1346 1347 /* From page 33 (page 39 of the PDF) of the GLSL 1.10 spec: 1348 * 1349 * "The second and third expressions must be the same type, but can 1350 * be of any type other than an array." 1351 */ 1352 if ((state->language_version <= 110) && type->is_array()) { 1353 _mesa_glsl_error(& loc, state, "Second and third operands of ?: " 1354 "operator must not be arrays."); 1355 error_emitted = true; 1356 } 1357 1358 ir_constant *cond_val = op[0]->constant_expression_value(); 1359 ir_constant *then_val = op[1]->constant_expression_value(); 1360 ir_constant *else_val = op[2]->constant_expression_value(); 1361 1362 if (then_instructions.is_empty() 1363 && else_instructions.is_empty() 1364 && (cond_val != NULL) && (then_val != NULL) && (else_val != NULL)) { 1365 result = (cond_val->value.b[0]) ? then_val : else_val; 1366 } else { 1367 ir_variable *const tmp = 1368 new(ctx) ir_variable(type, "conditional_tmp", ir_var_temporary); 1369 instructions->push_tail(tmp); 1370 1371 ir_if *const stmt = new(ctx) ir_if(op[0]); 1372 instructions->push_tail(stmt); 1373 1374 then_instructions.move_nodes_to(& stmt->then_instructions); 1375 ir_dereference *const then_deref = 1376 new(ctx) ir_dereference_variable(tmp); 1377 ir_assignment *const then_assign = 1378 new(ctx) ir_assignment(then_deref, op[1], NULL); 1379 stmt->then_instructions.push_tail(then_assign); 1380 1381 else_instructions.move_nodes_to(& stmt->else_instructions); 1382 ir_dereference *const else_deref = 1383 new(ctx) ir_dereference_variable(tmp); 1384 ir_assignment *const else_assign = 1385 new(ctx) ir_assignment(else_deref, op[2], NULL); 1386 stmt->else_instructions.push_tail(else_assign); 1387 1388 result = new(ctx) ir_dereference_variable(tmp); 1389 } 1390 break; 1391 } 1392 1393 case ast_pre_inc: 1394 case ast_pre_dec: { 1395 op[0] = this->subexpressions[0]->hir(instructions, state); 1396 if (op[0]->type->base_type == GLSL_TYPE_FLOAT) 1397 op[1] = new(ctx) ir_constant(1.0f); 1398 else 1399 op[1] = new(ctx) ir_constant(1); 1400 1401 type = arithmetic_result_type(op[0], op[1], false, state, & loc); 1402 1403 ir_rvalue *temp_rhs; 1404 temp_rhs = new(ctx) ir_expression(operations[this->oper], type, 1405 op[0], op[1]); 1406 1407 result = do_assignment(instructions, state, 1408 op[0]->clone(ctx, NULL), temp_rhs, 1409 this->subexpressions[0]->get_location()); 1410 type = result->type; 1411 error_emitted = op[0]->type->is_error(); 1412 break; 1413 } 1414 1415 case ast_post_inc: 1416 case ast_post_dec: { 1417 op[0] = this->subexpressions[0]->hir(instructions, state); 1418 if (op[0]->type->base_type == GLSL_TYPE_FLOAT) 1419 op[1] = new(ctx) ir_constant(1.0f); 1420 else 1421 op[1] = new(ctx) ir_constant(1); 1422 1423 error_emitted = op[0]->type->is_error() || op[1]->type->is_error(); 1424 1425 type = arithmetic_result_type(op[0], op[1], false, state, & loc); 1426 1427 ir_rvalue *temp_rhs; 1428 temp_rhs = new(ctx) ir_expression(operations[this->oper], type, 1429 op[0], op[1]); 1430 1431 /* Get a temporary of a copy of the lvalue before it's modified. 1432 * This may get thrown away later. 1433 */ 1434 result = get_lvalue_copy(instructions, op[0]->clone(ctx, NULL)); 1435 1436 (void)do_assignment(instructions, state, 1437 op[0]->clone(ctx, NULL), temp_rhs, 1438 this->subexpressions[0]->get_location()); 1439 1440 type = result->type; 1441 error_emitted = op[0]->type->is_error(); 1442 break; 1443 } 1444 1445 case ast_field_selection: 1446 result = _mesa_ast_field_selection_to_hir(this, instructions, state); 1447 type = result->type; 1448 break; 1449 1450 case ast_array_index: { 1451 YYLTYPE index_loc = subexpressions[1]->get_location(); 1452 1453 op[0] = subexpressions[0]->hir(instructions, state); 1454 op[1] = subexpressions[1]->hir(instructions, state); 1455 1456 error_emitted = op[0]->type->is_error() || op[1]->type->is_error(); 1457 1458 ir_rvalue *const array = op[0]; 1459 1460 result = new(ctx) ir_dereference_array(op[0], op[1]); 1461 1462 /* Do not use op[0] after this point. Use array. 1463 */ 1464 op[0] = NULL; 1465 1466 1467 if (error_emitted) 1468 break; 1469 1470 if (!array->type->is_array() 1471 && !array->type->is_matrix() 1472 && !array->type->is_vector()) { 1473 _mesa_glsl_error(& index_loc, state, 1474 "cannot dereference non-array / non-matrix / " 1475 "non-vector"); 1476 error_emitted = true; 1477 } 1478 1479 if (!op[1]->type->is_integer()) { 1480 _mesa_glsl_error(& index_loc, state, 1481 "array index must be integer type"); 1482 error_emitted = true; 1483 } else if (!op[1]->type->is_scalar()) { 1484 _mesa_glsl_error(& index_loc, state, 1485 "array index must be scalar"); 1486 error_emitted = true; 1487 } 1488 1489 /* If the array index is a constant expression and the array has a 1490 * declared size, ensure that the access is in-bounds. If the array 1491 * index is not a constant expression, ensure that the array has a 1492 * declared size. 1493 */ 1494 ir_constant *const const_index = op[1]->constant_expression_value(); 1495 if (const_index != NULL) { 1496 const int idx = const_index->value.i[0]; 1497 const char *type_name; 1498 unsigned bound = 0; 1499 1500 if (array->type->is_matrix()) { 1501 type_name = "matrix"; 1502 } else if (array->type->is_vector()) { 1503 type_name = "vector"; 1504 } else { 1505 type_name = "array"; 1506 } 1507 1508 /* From page 24 (page 30 of the PDF) of the GLSL 1.50 spec: 1509 * 1510 * "It is illegal to declare an array with a size, and then 1511 * later (in the same shader) index the same array with an 1512 * integral constant expression greater than or equal to the 1513 * declared size. It is also illegal to index an array with a 1514 * negative constant expression." 1515 */ 1516 if (array->type->is_matrix()) { 1517 if (array->type->row_type()->vector_elements <= idx) { 1518 bound = array->type->row_type()->vector_elements; 1519 } 1520 } else if (array->type->is_vector()) { 1521 if (array->type->vector_elements <= idx) { 1522 bound = array->type->vector_elements; 1523 } 1524 } else { 1525 if ((array->type->array_size() > 0) 1526 && (array->type->array_size() <= idx)) { 1527 bound = array->type->array_size(); 1528 } 1529 } 1530 1531 if (bound > 0) { 1532 _mesa_glsl_error(& loc, state, "%s index must be < %u", 1533 type_name, bound); 1534 error_emitted = true; 1535 } else if (idx < 0) { 1536 _mesa_glsl_error(& loc, state, "%s index must be >= 0", 1537 type_name); 1538 error_emitted = true; 1539 } 1540 1541 if (array->type->is_array()) { 1542 /* If the array is a variable dereference, it dereferences the 1543 * whole array, by definition. Use this to get the variable. 1544 * 1545 * FINISHME: Should some methods for getting / setting / testing 1546 * FINISHME: array access limits be added to ir_dereference? 1547 */ 1548 ir_variable *const v = array->whole_variable_referenced(); 1549 if ((v != NULL) && (unsigned(idx) > v->max_array_access)) 1550 v->max_array_access = idx; 1551 } 1552 } else if (array->type->array_size() == 0) { 1553 _mesa_glsl_error(&loc, state, "unsized array index must be constant"); 1554 } else { 1555 if (array->type->is_array()) { 1556 /* whole_variable_referenced can return NULL if the array is a 1557 * member of a structure. In this case it is safe to not update 1558 * the max_array_access field because it is never used for fields 1559 * of structures. 1560 */ 1561 ir_variable *v = array->whole_variable_referenced(); 1562 if (v != NULL) 1563 v->max_array_access = array->type->array_size(); 1564 } 1565 } 1566 1567 /* From page 23 (29 of the PDF) of the GLSL 1.30 spec: 1568 * 1569 * "Samplers aggregated into arrays within a shader (using square 1570 * brackets [ ]) can only be indexed with integral constant 1571 * expressions [...]." 1572 * 1573 * This restriction was added in GLSL 1.30. Shaders using earlier version 1574 * of the language should not be rejected by the compiler front-end for 1575 * using this construct. This allows useful things such as using a loop 1576 * counter as the index to an array of samplers. If the loop in unrolled, 1577 * the code should compile correctly. Instead, emit a warning. 1578 */ 1579 if (array->type->is_array() && 1580 array->type->element_type()->is_sampler() && 1581 const_index == NULL) { 1582 1583 if (state->language_version == 100) { 1584 _mesa_glsl_warning(&loc, state, 1585 "sampler arrays indexed with non-constant " 1586 "expressions is optional in GLSL ES 1.00"); 1587 } else if (state->language_version < 130) { 1588 _mesa_glsl_warning(&loc, state, 1589 "sampler arrays indexed with non-constant " 1590 "expressions is forbidden in GLSL 1.30 and " 1591 "later"); 1592 } else { 1593 _mesa_glsl_error(&loc, state, 1594 "sampler arrays indexed with non-constant " 1595 "expressions is forbidden in GLSL 1.30 and " 1596 "later"); 1597 error_emitted = true; 1598 } 1599 } 1600 1601 if (error_emitted) 1602 result->type = glsl_type::error_type; 1603 1604 type = result->type; 1605 break; 1606 } 1607 1608 case ast_function_call: 1609 /* Should *NEVER* get here. ast_function_call should always be handled 1610 * by ast_function_expression::hir. 1611 */ 1612 assert(0); 1613 break; 1614 1615 case ast_identifier: { 1616 /* ast_identifier can appear several places in a full abstract syntax 1617 * tree. This particular use must be at location specified in the grammar 1618 * as 'variable_identifier'. 1619 */ 1620 ir_variable *var = 1621 state->symbols->get_variable(this->primary_expression.identifier); 1622 1623 result = new(ctx) ir_dereference_variable(var); 1624 1625 if (var != NULL) { 1626 var->used = true; 1627 type = result->type; 1628 } else { 1629 _mesa_glsl_error(& loc, state, "`%s' undeclared", 1630 this->primary_expression.identifier); 1631 1632 error_emitted = true; 1633 } 1634 break; 1635 } 1636 1637 case ast_int_constant: 1638 type = glsl_type::int_type; 1639 result = new(ctx) ir_constant(this->primary_expression.int_constant); 1640 break; 1641 1642 case ast_uint_constant: 1643 type = glsl_type::uint_type; 1644 result = new(ctx) ir_constant(this->primary_expression.uint_constant); 1645 break; 1646 1647 case ast_float_constant: 1648 type = glsl_type::float_type; 1649 result = new(ctx) ir_constant(this->primary_expression.float_constant); 1650 break; 1651 1652 case ast_bool_constant: 1653 type = glsl_type::bool_type; 1654 result = new(ctx) ir_constant(bool(this->primary_expression.bool_constant)); 1655 break; 1656 1657 case ast_sequence: { 1658 /* It should not be possible to generate a sequence in the AST without 1659 * any expressions in it. 1660 */ 1661 assert(!this->expressions.is_empty()); 1662 1663 /* The r-value of a sequence is the last expression in the sequence. If 1664 * the other expressions in the sequence do not have side-effects (and 1665 * therefore add instructions to the instruction list), they get dropped 1666 * on the floor. 1667 */ 1668 foreach_list_typed (ast_node, ast, link, &this->expressions) 1669 result = ast->hir(instructions, state); 1670 1671 type = result->type; 1672 1673 /* Any errors should have already been emitted in the loop above. 1674 */ 1675 error_emitted = true; 1676 break; 1677 } 1678 } 1679 1680 if (type->is_error() && !error_emitted) 1681 _mesa_glsl_error(& loc, state, "type mismatch"); 1682 1683 return result; 1684} 1685 1686 1687ir_rvalue * 1688ast_expression_statement::hir(exec_list *instructions, 1689 struct _mesa_glsl_parse_state *state) 1690{ 1691 /* It is possible to have expression statements that don't have an 1692 * expression. This is the solitary semicolon: 1693 * 1694 * for (i = 0; i < 5; i++) 1695 * ; 1696 * 1697 * In this case the expression will be NULL. Test for NULL and don't do 1698 * anything in that case. 1699 */ 1700 if (expression != NULL) 1701 expression->hir(instructions, state); 1702 1703 /* Statements do not have r-values. 1704 */ 1705 return NULL; 1706} 1707 1708 1709ir_rvalue * 1710ast_compound_statement::hir(exec_list *instructions, 1711 struct _mesa_glsl_parse_state *state) 1712{ 1713 if (new_scope) 1714 state->symbols->push_scope(); 1715 1716 foreach_list_typed (ast_node, ast, link, &this->statements) 1717 ast->hir(instructions, state); 1718 1719 if (new_scope) 1720 state->symbols->pop_scope(); 1721 1722 /* Compound statements do not have r-values. 1723 */ 1724 return NULL; 1725} 1726 1727 1728static const glsl_type * 1729process_array_type(YYLTYPE *loc, const glsl_type *base, ast_node *array_size, 1730 struct _mesa_glsl_parse_state *state) 1731{ 1732 unsigned length = 0; 1733 1734 /* FINISHME: Reject delcarations of multidimensional arrays. */ 1735 1736 if (array_size != NULL) { 1737 exec_list dummy_instructions; 1738 ir_rvalue *const ir = array_size->hir(& dummy_instructions, state); 1739 YYLTYPE loc = array_size->get_location(); 1740 1741 /* FINISHME: Verify that the grammar forbids side-effects in array 1742 * FINISHME: sizes. i.e., 'vec4 [x = 12] data' 1743 */ 1744 assert(dummy_instructions.is_empty()); 1745 1746 if (ir != NULL) { 1747 if (!ir->type->is_integer()) { 1748 _mesa_glsl_error(& loc, state, "array size must be integer type"); 1749 } else if (!ir->type->is_scalar()) { 1750 _mesa_glsl_error(& loc, state, "array size must be scalar type"); 1751 } else { 1752 ir_constant *const size = ir->constant_expression_value(); 1753 1754 if (size == NULL) { 1755 _mesa_glsl_error(& loc, state, "array size must be a " 1756 "constant valued expression"); 1757 } else if (size->value.i[0] <= 0) { 1758 _mesa_glsl_error(& loc, state, "array size must be > 0"); 1759 } else { 1760 assert(size->type == ir->type); 1761 length = size->value.u[0]; 1762 } 1763 } 1764 } 1765 } else if (state->es_shader) { 1766 /* Section 10.17 of the GLSL ES 1.00 specification states that unsized 1767 * array declarations have been removed from the language. 1768 */ 1769 _mesa_glsl_error(loc, state, "unsized array declarations are not " 1770 "allowed in GLSL ES 1.00."); 1771 } 1772 1773 return glsl_type::get_array_instance(base, length); 1774} 1775 1776 1777const glsl_type * 1778ast_type_specifier::glsl_type(const char **name, 1779 struct _mesa_glsl_parse_state *state) const 1780{ 1781 const struct glsl_type *type; 1782 1783 type = state->symbols->get_type(this->type_name); 1784 *name = this->type_name; 1785 1786 if (this->is_array) { 1787 YYLTYPE loc = this->get_location(); 1788 type = process_array_type(&loc, type, this->array_size, state); 1789 } 1790 1791 return type; 1792} 1793 1794 1795static void 1796apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual, 1797 ir_variable *var, 1798 struct _mesa_glsl_parse_state *state, 1799 YYLTYPE *loc) 1800{ 1801 if (qual->flags.q.invariant) { 1802 if (var->used) { 1803 _mesa_glsl_error(loc, state, 1804 "variable `%s' may not be redeclared " 1805 "`invariant' after being used", 1806 var->name); 1807 } else { 1808 var->invariant = 1; 1809 } 1810 } 1811 1812 /* FINISHME: Mark 'in' variables at global scope as read-only. */ 1813 if (qual->flags.q.constant || qual->flags.q.attribute 1814 || qual->flags.q.uniform 1815 || (qual->flags.q.varying && (state->target == fragment_shader))) 1816 var->read_only = 1; 1817 1818 if (qual->flags.q.centroid) 1819 var->centroid = 1; 1820 1821 if (qual->flags.q.attribute && state->target != vertex_shader) { 1822 var->type = glsl_type::error_type; 1823 _mesa_glsl_error(loc, state, 1824 "`attribute' variables may not be declared in the " 1825 "%s shader", 1826 _mesa_glsl_shader_target_name(state->target)); 1827 } 1828 1829 /* From page 25 (page 31 of the PDF) of the GLSL 1.10 spec: 1830 * 1831 * "The varying qualifier can be used only with the data types 1832 * float, vec2, vec3, vec4, mat2, mat3, and mat4, or arrays of 1833 * these." 1834 */ 1835 if (qual->flags.q.varying) { 1836 const glsl_type *non_array_type; 1837 1838 if (var->type && var->type->is_array()) 1839 non_array_type = var->type->fields.array; 1840 else 1841 non_array_type = var->type; 1842 1843 if (non_array_type && non_array_type->base_type != GLSL_TYPE_FLOAT) { 1844 var->type = glsl_type::error_type; 1845 _mesa_glsl_error(loc, state, 1846 "varying variables must be of base type float"); 1847 } 1848 } 1849 1850 /* If there is no qualifier that changes the mode of the variable, leave 1851 * the setting alone. 1852 */ 1853 if (qual->flags.q.in && qual->flags.q.out) 1854 var->mode = ir_var_inout; 1855 else if (qual->flags.q.attribute || qual->flags.q.in 1856 || (qual->flags.q.varying && (state->target == fragment_shader))) 1857 var->mode = ir_var_in; 1858 else if (qual->flags.q.out 1859 || (qual->flags.q.varying && (state->target == vertex_shader))) 1860 var->mode = ir_var_out; 1861 else if (qual->flags.q.uniform) 1862 var->mode = ir_var_uniform; 1863 1864 if (state->all_invariant && (state->current_function == NULL)) { 1865 switch (state->target) { 1866 case vertex_shader: 1867 if (var->mode == ir_var_out) 1868 var->invariant = true; 1869 break; 1870 case geometry_shader: 1871 if ((var->mode == ir_var_in) || (var->mode == ir_var_out)) 1872 var->invariant = true; 1873 break; 1874 case fragment_shader: 1875 if (var->mode == ir_var_in) 1876 var->invariant = true; 1877 break; 1878 } 1879 } 1880 1881 if (qual->flags.q.flat) 1882 var->interpolation = ir_var_flat; 1883 else if (qual->flags.q.noperspective) 1884 var->interpolation = ir_var_noperspective; 1885 else 1886 var->interpolation = ir_var_smooth; 1887 1888 var->pixel_center_integer = qual->flags.q.pixel_center_integer; 1889 var->origin_upper_left = qual->flags.q.origin_upper_left; 1890 if ((qual->flags.q.origin_upper_left || qual->flags.q.pixel_center_integer) 1891 && (strcmp(var->name, "gl_FragCoord") != 0)) { 1892 const char *const qual_string = (qual->flags.q.origin_upper_left) 1893 ? "origin_upper_left" : "pixel_center_integer"; 1894 1895 _mesa_glsl_error(loc, state, 1896 "layout qualifier `%s' can only be applied to " 1897 "fragment shader input `gl_FragCoord'", 1898 qual_string); 1899 } 1900 1901 if (qual->flags.q.explicit_location) { 1902 const bool global_scope = (state->current_function == NULL); 1903 bool fail = false; 1904 const char *string = ""; 1905 1906 /* In the vertex shader only shader inputs can be given explicit 1907 * locations. 1908 * 1909 * In the fragment shader only shader outputs can be given explicit 1910 * locations. 1911 */ 1912 switch (state->target) { 1913 case vertex_shader: 1914 if (!global_scope || (var->mode != ir_var_in)) { 1915 fail = true; 1916 string = "input"; 1917 } 1918 break; 1919 1920 case geometry_shader: 1921 _mesa_glsl_error(loc, state, 1922 "geometry shader variables cannot be given " 1923 "explicit locations\n"); 1924 break; 1925 1926 case fragment_shader: 1927 if (!global_scope || (var->mode != ir_var_in)) { 1928 fail = true; 1929 string = "output"; 1930 } 1931 break; 1932 }; 1933 1934 if (fail) { 1935 _mesa_glsl_error(loc, state, 1936 "only %s shader %s variables can be given an " 1937 "explicit location\n", 1938 _mesa_glsl_shader_target_name(state->target), 1939 string); 1940 } else { 1941 var->explicit_location = true; 1942 1943 /* This bit of silliness is needed because invalid explicit locations 1944 * are supposed to be flagged during linking. Small negative values 1945 * biased by VERT_ATTRIB_GENERIC0 or FRAG_RESULT_DATA0 could alias 1946 * built-in values (e.g., -16+VERT_ATTRIB_GENERIC0 = VERT_ATTRIB_POS). 1947 * The linker needs to be able to differentiate these cases. This 1948 * ensures that negative values stay negative. 1949 */ 1950 if (qual->location >= 0) { 1951 var->location = (state->target == vertex_shader) 1952 ? (qual->location + VERT_ATTRIB_GENERIC0) 1953 : (qual->location + FRAG_RESULT_DATA0); 1954 } else { 1955 var->location = qual->location; 1956 } 1957 } 1958 } 1959 1960 /* Does the declaration use the 'layout' keyword? 1961 */ 1962 const bool uses_layout = qual->flags.q.pixel_center_integer 1963 || qual->flags.q.origin_upper_left 1964 || qual->flags.q.explicit_location; 1965 1966 /* Does the declaration use the deprecated 'attribute' or 'varying' 1967 * keywords? 1968 */ 1969 const bool uses_deprecated_qualifier = qual->flags.q.attribute 1970 || qual->flags.q.varying; 1971 1972 /* Is the 'layout' keyword used with parameters that allow relaxed checking. 1973 * Many implementations of GL_ARB_fragment_coord_conventions_enable and some 1974 * implementations (only Mesa?) GL_ARB_explicit_attrib_location_enable 1975 * allowed the layout qualifier to be used with 'varying' and 'attribute'. 1976 * These extensions and all following extensions that add the 'layout' 1977 * keyword have been modified to require the use of 'in' or 'out'. 1978 * 1979 * The following extension do not allow the deprecated keywords: 1980 * 1981 * GL_AMD_conservative_depth 1982 * GL_ARB_gpu_shader5 1983 * GL_ARB_separate_shader_objects 1984 * GL_ARB_tesselation_shader 1985 * GL_ARB_transform_feedback3 1986 * GL_ARB_uniform_buffer_object 1987 * 1988 * It is unknown whether GL_EXT_shader_image_load_store or GL_NV_gpu_shader5 1989 * allow layout with the deprecated keywords. 1990 */ 1991 const bool relaxed_layout_qualifier_checking = 1992 state->ARB_fragment_coord_conventions_enable; 1993 1994 if (uses_layout && uses_deprecated_qualifier) { 1995 if (relaxed_layout_qualifier_checking) { 1996 _mesa_glsl_warning(loc, state, 1997 "`layout' qualifier may not be used with " 1998 "`attribute' or `varying'"); 1999 } else { 2000 _mesa_glsl_error(loc, state, 2001 "`layout' qualifier may not be used with " 2002 "`attribute' or `varying'"); 2003 } 2004 } 2005 2006 if (var->type->is_array() && state->language_version != 110) { 2007 var->array_lvalue = true; 2008 } 2009} 2010 2011 2012ir_rvalue * 2013ast_declarator_list::hir(exec_list *instructions, 2014 struct _mesa_glsl_parse_state *state) 2015{ 2016 void *ctx = state; 2017 const struct glsl_type *decl_type; 2018 const char *type_name = NULL; 2019 ir_rvalue *result = NULL; 2020 YYLTYPE loc = this->get_location(); 2021 2022 /* From page 46 (page 52 of the PDF) of the GLSL 1.50 spec: 2023 * 2024 * "To ensure that a particular output variable is invariant, it is 2025 * necessary to use the invariant qualifier. It can either be used to 2026 * qualify a previously declared variable as being invariant 2027 * 2028 * invariant gl_Position; // make existing gl_Position be invariant" 2029 * 2030 * In these cases the parser will set the 'invariant' flag in the declarator 2031 * list, and the type will be NULL. 2032 */ 2033 if (this->invariant) { 2034 assert(this->type == NULL); 2035 2036 if (state->current_function != NULL) { 2037 _mesa_glsl_error(& loc, state, 2038 "All uses of `invariant' keyword must be at global " 2039 "scope\n"); 2040 } 2041 2042 foreach_list_typed (ast_declaration, decl, link, &this->declarations) { 2043 assert(!decl->is_array); 2044 assert(decl->array_size == NULL); 2045 assert(decl->initializer == NULL); 2046 2047 ir_variable *const earlier = 2048 state->symbols->get_variable(decl->identifier); 2049 if (earlier == NULL) { 2050 _mesa_glsl_error(& loc, state, 2051 "Undeclared variable `%s' cannot be marked " 2052 "invariant\n", decl->identifier); 2053 } else if ((state->target == vertex_shader) 2054 && (earlier->mode != ir_var_out)) { 2055 _mesa_glsl_error(& loc, state, 2056 "`%s' cannot be marked invariant, vertex shader " 2057 "outputs only\n", decl->identifier); 2058 } else if ((state->target == fragment_shader) 2059 && (earlier->mode != ir_var_in)) { 2060 _mesa_glsl_error(& loc, state, 2061 "`%s' cannot be marked invariant, fragment shader " 2062 "inputs only\n", decl->identifier); 2063 } else if (earlier->used) { 2064 _mesa_glsl_error(& loc, state, 2065 "variable `%s' may not be redeclared " 2066 "`invariant' after being used", 2067 earlier->name); 2068 } else { 2069 earlier->invariant = true; 2070 } 2071 } 2072 2073 /* Invariant redeclarations do not have r-values. 2074 */ 2075 return NULL; 2076 } 2077 2078 assert(this->type != NULL); 2079 assert(!this->invariant); 2080 2081 /* The type specifier may contain a structure definition. Process that 2082 * before any of the variable declarations. 2083 */ 2084 (void) this->type->specifier->hir(instructions, state); 2085 2086 decl_type = this->type->specifier->glsl_type(& type_name, state); 2087 if (this->declarations.is_empty()) { 2088 /* The only valid case where the declaration list can be empty is when 2089 * the declaration is setting the default precision of a built-in type 2090 * (e.g., 'precision highp vec4;'). 2091 */ 2092 2093 if (decl_type != NULL) { 2094 } else { 2095 _mesa_glsl_error(& loc, state, "incomplete declaration"); 2096 } 2097 } 2098 2099 foreach_list_typed (ast_declaration, decl, link, &this->declarations) { 2100 const struct glsl_type *var_type; 2101 ir_variable *var; 2102 2103 /* FINISHME: Emit a warning if a variable declaration shadows a 2104 * FINISHME: declaration at a higher scope. 2105 */ 2106 2107 if ((decl_type == NULL) || decl_type->is_void()) { 2108 if (type_name != NULL) { 2109 _mesa_glsl_error(& loc, state, 2110 "invalid type `%s' in declaration of `%s'", 2111 type_name, decl->identifier); 2112 } else { 2113 _mesa_glsl_error(& loc, state, 2114 "invalid type in declaration of `%s'", 2115 decl->identifier); 2116 } 2117 continue; 2118 } 2119 2120 if (decl->is_array) { 2121 var_type = process_array_type(&loc, decl_type, decl->array_size, 2122 state); 2123 } else { 2124 var_type = decl_type; 2125 } 2126 2127 var = new(ctx) ir_variable(var_type, decl->identifier, ir_var_auto); 2128 2129 /* From page 22 (page 28 of the PDF) of the GLSL 1.10 specification; 2130 * 2131 * "Global variables can only use the qualifiers const, 2132 * attribute, uni form, or varying. Only one may be 2133 * specified. 2134 * 2135 * Local variables can only use the qualifier const." 2136 * 2137 * This is relaxed in GLSL 1.30. It is also relaxed by any extension 2138 * that adds the 'layout' keyword. 2139 */ 2140 if ((state->language_version < 130) 2141 && !state->ARB_explicit_attrib_location_enable 2142 && !state->ARB_fragment_coord_conventions_enable) { 2143 if (this->type->qualifier.flags.q.out) { 2144 _mesa_glsl_error(& loc, state, 2145 "`out' qualifier in declaration of `%s' " 2146 "only valid for function parameters in %s.", 2147 decl->identifier, state->version_string); 2148 } 2149 if (this->type->qualifier.flags.q.in) { 2150 _mesa_glsl_error(& loc, state, 2151 "`in' qualifier in declaration of `%s' " 2152 "only valid for function parameters in %s.", 2153 decl->identifier, state->version_string); 2154 } 2155 /* FINISHME: Test for other invalid qualifiers. */ 2156 } 2157 2158 apply_type_qualifier_to_variable(& this->type->qualifier, var, state, 2159 & loc); 2160 2161 if (this->type->qualifier.flags.q.invariant) { 2162 if ((state->target == vertex_shader) && !(var->mode == ir_var_out || 2163 var->mode == ir_var_inout)) { 2164 /* FINISHME: Note that this doesn't work for invariant on 2165 * a function signature outval 2166 */ 2167 _mesa_glsl_error(& loc, state, 2168 "`%s' cannot be marked invariant, vertex shader " 2169 "outputs only\n", var->name); 2170 } else if ((state->target == fragment_shader) && 2171 !(var->mode == ir_var_in || var->mode == ir_var_inout)) { 2172 /* FINISHME: Note that this doesn't work for invariant on 2173 * a function signature inval 2174 */ 2175 _mesa_glsl_error(& loc, state, 2176 "`%s' cannot be marked invariant, fragment shader " 2177 "inputs only\n", var->name); 2178 } 2179 } 2180 2181 if (state->current_function != NULL) { 2182 const char *mode = NULL; 2183 const char *extra = ""; 2184 2185 /* There is no need to check for 'inout' here because the parser will 2186 * only allow that in function parameter lists. 2187 */ 2188 if (this->type->qualifier.flags.q.attribute) { 2189 mode = "attribute"; 2190 } else if (this->type->qualifier.flags.q.uniform) { 2191 mode = "uniform"; 2192 } else if (this->type->qualifier.flags.q.varying) { 2193 mode = "varying"; 2194 } else if (this->type->qualifier.flags.q.in) { 2195 mode = "in"; 2196 extra = " or in function parameter list"; 2197 } else if (this->type->qualifier.flags.q.out) { 2198 mode = "out"; 2199 extra = " or in function parameter list"; 2200 } 2201 2202 if (mode) { 2203 _mesa_glsl_error(& loc, state, 2204 "%s variable `%s' must be declared at " 2205 "global scope%s", 2206 mode, var->name, extra); 2207 } 2208 } else if (var->mode == ir_var_in) { 2209 if (state->target == vertex_shader) { 2210 bool error_emitted = false; 2211 2212 /* From page 31 (page 37 of the PDF) of the GLSL 1.50 spec: 2213 * 2214 * "Vertex shader inputs can only be float, floating-point 2215 * vectors, matrices, signed and unsigned integers and integer 2216 * vectors. Vertex shader inputs can also form arrays of these 2217 * types, but not structures." 2218 * 2219 * From page 31 (page 27 of the PDF) of the GLSL 1.30 spec: 2220 * 2221 * "Vertex shader inputs can only be float, floating-point 2222 * vectors, matrices, signed and unsigned integers and integer 2223 * vectors. They cannot be arrays or structures." 2224 * 2225 * From page 23 (page 29 of the PDF) of the GLSL 1.20 spec: 2226 * 2227 * "The attribute qualifier can be used only with float, 2228 * floating-point vectors, and matrices. Attribute variables 2229 * cannot be declared as arrays or structures." 2230 */ 2231 const glsl_type *check_type = var->type->is_array() 2232 ? var->type->fields.array : var->type; 2233 2234 switch (check_type->base_type) { 2235 case GLSL_TYPE_FLOAT: 2236 break; 2237 case GLSL_TYPE_UINT: 2238 case GLSL_TYPE_INT: 2239 if (state->language_version > 120) 2240 break; 2241 /* FALLTHROUGH */ 2242 default: 2243 _mesa_glsl_error(& loc, state, 2244 "vertex shader input / attribute cannot have " 2245 "type %s`%s'", 2246 var->type->is_array() ? "array of " : "", 2247 check_type->name); 2248 error_emitted = true; 2249 } 2250 2251 if (!error_emitted && (state->language_version <= 130) 2252 && var->type->is_array()) { 2253 _mesa_glsl_error(& loc, state, 2254 "vertex shader input / attribute cannot have " 2255 "array type"); 2256 error_emitted = true; 2257 } 2258 } 2259 } 2260 2261 /* Integer vertex outputs must be qualified with 'flat'. 2262 * 2263 * From section 4.3.6 of the GLSL 1.30 spec: 2264 * "If a vertex output is a signed or unsigned integer or integer 2265 * vector, then it must be qualified with the interpolation qualifier 2266 * flat." 2267 */ 2268 if (state->language_version >= 130 2269 && state->target == vertex_shader 2270 && state->current_function == NULL 2271 && var->type->is_integer() 2272 && var->mode == ir_var_out 2273 && var->interpolation != ir_var_flat) { 2274 2275 _mesa_glsl_error(&loc, state, "If a vertex output is an integer, " 2276 "then it must be qualified with 'flat'"); 2277 } 2278 2279 2280 /* Interpolation qualifiers cannot be applied to 'centroid' and 2281 * 'centroid varying'. 2282 * 2283 * From page 29 (page 35 of the PDF) of the GLSL 1.30 spec: 2284 * "interpolation qualifiers may only precede the qualifiers in, 2285 * centroid in, out, or centroid out in a declaration. They do not apply 2286 * to the deprecated storage qualifiers varying or centroid varying." 2287 */ 2288 if (state->language_version >= 130 2289 && this->type->qualifier.has_interpolation() 2290 && this->type->qualifier.flags.q.varying) { 2291 2292 const char *i = this->type->qualifier.interpolation_string(); 2293 assert(i != NULL); 2294 const char *s; 2295 if (this->type->qualifier.flags.q.centroid) 2296 s = "centroid varying"; 2297 else 2298 s = "varying"; 2299 2300 _mesa_glsl_error(&loc, state, 2301 "qualifier '%s' cannot be applied to the " 2302 "deprecated storage qualifier '%s'", i, s); 2303 } 2304 2305 2306 /* Interpolation qualifiers can only apply to vertex shader outputs and 2307 * fragment shader inputs. 2308 * 2309 * From page 29 (page 35 of the PDF) of the GLSL 1.30 spec: 2310 * "Outputs from a vertex shader (out) and inputs to a fragment 2311 * shader (in) can be further qualified with one or more of these 2312 * interpolation qualifiers" 2313 */ 2314 if (state->language_version >= 130 2315 && this->type->qualifier.has_interpolation()) { 2316 2317 const char *i = this->type->qualifier.interpolation_string(); 2318 assert(i != NULL); 2319 2320 switch (state->target) { 2321 case vertex_shader: 2322 if (this->type->qualifier.flags.q.in) { 2323 _mesa_glsl_error(&loc, state, 2324 "qualifier '%s' cannot be applied to vertex " 2325 "shader inputs", i); 2326 } 2327 break; 2328 case fragment_shader: 2329 if (this->type->qualifier.flags.q.out) { 2330 _mesa_glsl_error(&loc, state, 2331 "qualifier '%s' cannot be applied to fragment " 2332 "shader outputs", i); 2333 } 2334 break; 2335 default: 2336 assert(0); 2337 } 2338 } 2339 2340 2341 /* From section 4.3.4 of the GLSL 1.30 spec: 2342 * "It is an error to use centroid in in a vertex shader." 2343 */ 2344 if (state->language_version >= 130 2345 && this->type->qualifier.flags.q.centroid 2346 && this->type->qualifier.flags.q.in 2347 && state->target == vertex_shader) { 2348 2349 _mesa_glsl_error(&loc, state, 2350 "'centroid in' cannot be used in a vertex shader"); 2351 } 2352 2353 2354 /* Precision qualifiers exists only in GLSL versions 1.00 and >= 1.30. 2355 */ 2356 if (this->type->specifier->precision != ast_precision_none 2357 && state->language_version != 100 2358 && state->language_version < 130) { 2359 2360 _mesa_glsl_error(&loc, state, 2361 "precision qualifiers are supported only in GLSL ES " 2362 "1.00, and GLSL 1.30 and later"); 2363 } 2364 2365 2366 /* Precision qualifiers only apply to floating point and integer types. 2367 * 2368 * From section 4.5.2 of the GLSL 1.30 spec: 2369 * "Any floating point or any integer declaration can have the type 2370 * preceded by one of these precision qualifiers [...] Literal 2371 * constants do not have precision qualifiers. Neither do Boolean 2372 * variables. 2373 */ 2374 if (this->type->specifier->precision != ast_precision_none 2375 && !var->type->is_float() 2376 && !var->type->is_integer() 2377 && !(var->type->is_array() 2378 && (var->type->fields.array->is_float() 2379 || var->type->fields.array->is_integer()))) { 2380 2381 _mesa_glsl_error(&loc, state, 2382 "precision qualifiers apply only to floating point " 2383 "and integer types"); 2384 } 2385 2386 /* Process the initializer and add its instructions to a temporary 2387 * list. This list will be added to the instruction stream (below) after 2388 * the declaration is added. This is done because in some cases (such as 2389 * redeclarations) the declaration may not actually be added to the 2390 * instruction stream. 2391 */ 2392 exec_list initializer_instructions; 2393 if (decl->initializer != NULL) { 2394 YYLTYPE initializer_loc = decl->initializer->get_location(); 2395 2396 /* From page 24 (page 30 of the PDF) of the GLSL 1.10 spec: 2397 * 2398 * "All uniform variables are read-only and are initialized either 2399 * directly by an application via API commands, or indirectly by 2400 * OpenGL." 2401 */ 2402 if ((state->language_version <= 110) 2403 && (var->mode == ir_var_uniform)) { 2404 _mesa_glsl_error(& initializer_loc, state, 2405 "cannot initialize uniforms in GLSL 1.10"); 2406 } 2407 2408 if (var->type->is_sampler()) { 2409 _mesa_glsl_error(& initializer_loc, state, 2410 "cannot initialize samplers"); 2411 } 2412 2413 if ((var->mode == ir_var_in) && (state->current_function == NULL)) { 2414 _mesa_glsl_error(& initializer_loc, state, 2415 "cannot initialize %s shader input / %s", 2416 _mesa_glsl_shader_target_name(state->target), 2417 (state->target == vertex_shader) 2418 ? "attribute" : "varying"); 2419 } 2420 2421 ir_dereference *const lhs = new(ctx) ir_dereference_variable(var); 2422 ir_rvalue *rhs = decl->initializer->hir(&initializer_instructions, 2423 state); 2424 2425 /* Calculate the constant value if this is a const or uniform 2426 * declaration. 2427 */ 2428 if (this->type->qualifier.flags.q.constant 2429 || this->type->qualifier.flags.q.uniform) { 2430 ir_rvalue *new_rhs = validate_assignment(state, var->type, rhs); 2431 if (new_rhs != NULL) { 2432 rhs = new_rhs; 2433 2434 ir_constant *constant_value = rhs->constant_expression_value(); 2435 if (!constant_value) { 2436 _mesa_glsl_error(& initializer_loc, state, 2437 "initializer of %s variable `%s' must be a " 2438 "constant expression", 2439 (this->type->qualifier.flags.q.constant) 2440 ? "const" : "uniform", 2441 decl->identifier); 2442 if (var->type->is_numeric()) { 2443 /* Reduce cascading errors. */ 2444 var->constant_value = ir_constant::zero(ctx, var->type); 2445 } 2446 } else { 2447 rhs = constant_value; 2448 var->constant_value = constant_value; 2449 } 2450 } else { 2451 _mesa_glsl_error(&initializer_loc, state, 2452 "initializer of type %s cannot be assigned to " 2453 "variable of type %s", 2454 rhs->type->name, var->type->name); 2455 if (var->type->is_numeric()) { 2456 /* Reduce cascading errors. */ 2457 var->constant_value = ir_constant::zero(ctx, var->type); 2458 } 2459 } 2460 } 2461 2462 if (rhs && !rhs->type->is_error()) { 2463 bool temp = var->read_only; 2464 if (this->type->qualifier.flags.q.constant) 2465 var->read_only = false; 2466 2467 /* Never emit code to initialize a uniform. 2468 */ 2469 const glsl_type *initializer_type; 2470 if (!this->type->qualifier.flags.q.uniform) { 2471 result = do_assignment(&initializer_instructions, state, 2472 lhs, rhs, 2473 this->get_location()); 2474 initializer_type = result->type; 2475 } else 2476 initializer_type = rhs->type; 2477 2478 /* If the declared variable is an unsized array, it must inherrit 2479 * its full type from the initializer. A declaration such as 2480 * 2481 * uniform float a[] = float[](1.0, 2.0, 3.0, 3.0); 2482 * 2483 * becomes 2484 * 2485 * uniform float a[4] = float[](1.0, 2.0, 3.0, 3.0); 2486 * 2487 * The assignment generated in the if-statement (below) will also 2488 * automatically handle this case for non-uniforms. 2489 * 2490 * If the declared variable is not an array, the types must 2491 * already match exactly. As a result, the type assignment 2492 * here can be done unconditionally. For non-uniforms the call 2493 * to do_assignment can change the type of the initializer (via 2494 * the implicit conversion rules). For uniforms the initializer 2495 * must be a constant expression, and the type of that expression 2496 * was validated above. 2497 */ 2498 var->type = initializer_type; 2499 2500 var->read_only = temp; 2501 } 2502 } 2503 2504 /* From page 23 (page 29 of the PDF) of the GLSL 1.10 spec: 2505 * 2506 * "It is an error to write to a const variable outside of 2507 * its declaration, so they must be initialized when 2508 * declared." 2509 */ 2510 if (this->type->qualifier.flags.q.constant && decl->initializer == NULL) { 2511 _mesa_glsl_error(& loc, state, 2512 "const declaration of `%s' must be initialized", 2513 decl->identifier); 2514 } 2515 2516 /* Check if this declaration is actually a re-declaration, either to 2517 * resize an array or add qualifiers to an existing variable. 2518 * 2519 * This is allowed for variables in the current scope, or when at 2520 * global scope (for built-ins in the implicit outer scope). 2521 */ 2522 ir_variable *earlier = state->symbols->get_variable(decl->identifier); 2523 if (earlier != NULL && (state->current_function == NULL || 2524 state->symbols->name_declared_this_scope(decl->identifier))) { 2525 2526 /* From page 24 (page 30 of the PDF) of the GLSL 1.50 spec, 2527 * 2528 * "It is legal to declare an array without a size and then 2529 * later re-declare the same name as an array of the same 2530 * type and specify a size." 2531 */ 2532 if ((earlier->type->array_size() == 0) 2533 && var->type->is_array() 2534 && (var->type->element_type() == earlier->type->element_type())) { 2535 /* FINISHME: This doesn't match the qualifiers on the two 2536 * FINISHME: declarations. It's not 100% clear whether this is 2537 * FINISHME: required or not. 2538 */ 2539 2540 /* From page 54 (page 60 of the PDF) of the GLSL 1.20 spec: 2541 * 2542 * "The size [of gl_TexCoord] can be at most 2543 * gl_MaxTextureCoords." 2544 */ 2545 const unsigned size = unsigned(var->type->array_size()); 2546 if ((strcmp("gl_TexCoord", var->name) == 0) 2547 && (size > state->Const.MaxTextureCoords)) { 2548 YYLTYPE loc = this->get_location(); 2549 2550 _mesa_glsl_error(& loc, state, "`gl_TexCoord' array size cannot " 2551 "be larger than gl_MaxTextureCoords (%u)\n", 2552 state->Const.MaxTextureCoords); 2553 } else if ((size > 0) && (size <= earlier->max_array_access)) { 2554 YYLTYPE loc = this->get_location(); 2555 2556 _mesa_glsl_error(& loc, state, "array size must be > %u due to " 2557 "previous access", 2558 earlier->max_array_access); 2559 } 2560 2561 earlier->type = var->type; 2562 delete var; 2563 var = NULL; 2564 } else if (state->ARB_fragment_coord_conventions_enable 2565 && strcmp(var->name, "gl_FragCoord") == 0 2566 && earlier->type == var->type 2567 && earlier->mode == var->mode) { 2568 /* Allow redeclaration of gl_FragCoord for ARB_fcc layout 2569 * qualifiers. 2570 */ 2571 earlier->origin_upper_left = var->origin_upper_left; 2572 earlier->pixel_center_integer = var->pixel_center_integer; 2573 2574 /* According to section 4.3.7 of the GLSL 1.30 spec, 2575 * the following built-in varaibles can be redeclared with an 2576 * interpolation qualifier: 2577 * * gl_FrontColor 2578 * * gl_BackColor 2579 * * gl_FrontSecondaryColor 2580 * * gl_BackSecondaryColor 2581 * * gl_Color 2582 * * gl_SecondaryColor 2583 */ 2584 } else if (state->language_version >= 130 2585 && (strcmp(var->name, "gl_FrontColor") == 0 2586 || strcmp(var->name, "gl_BackColor") == 0 2587 || strcmp(var->name, "gl_FrontSecondaryColor") == 0 2588 || strcmp(var->name, "gl_BackSecondaryColor") == 0 2589 || strcmp(var->name, "gl_Color") == 0 2590 || strcmp(var->name, "gl_SecondaryColor") == 0) 2591 && earlier->type == var->type 2592 && earlier->mode == var->mode) { 2593 earlier->interpolation = var->interpolation; 2594 } else { 2595 YYLTYPE loc = this->get_location(); 2596 _mesa_glsl_error(&loc, state, "`%s' redeclared", decl->identifier); 2597 } 2598 2599 continue; 2600 } 2601 2602 /* By now, we know it's a new variable declaration (we didn't hit the 2603 * above "continue"). 2604 * 2605 * From page 15 (page 21 of the PDF) of the GLSL 1.10 spec, 2606 * 2607 * "Identifiers starting with "gl_" are reserved for use by 2608 * OpenGL, and may not be declared in a shader as either a 2609 * variable or a function." 2610 */ 2611 if (strncmp(decl->identifier, "gl_", 3) == 0) 2612 _mesa_glsl_error(& loc, state, 2613 "identifier `%s' uses reserved `gl_' prefix", 2614 decl->identifier); 2615 2616 /* Add the variable to the symbol table. Note that the initializer's 2617 * IR was already processed earlier (though it hasn't been emitted yet), 2618 * without the variable in scope. 2619 * 2620 * This differs from most C-like languages, but it follows the GLSL 2621 * specification. From page 28 (page 34 of the PDF) of the GLSL 1.50 2622 * spec: 2623 * 2624 * "Within a declaration, the scope of a name starts immediately 2625 * after the initializer if present or immediately after the name 2626 * being declared if not." 2627 */ 2628 if (!state->symbols->add_variable(var)) { 2629 YYLTYPE loc = this->get_location(); 2630 _mesa_glsl_error(&loc, state, "name `%s' already taken in the " 2631 "current scope", decl->identifier); 2632 continue; 2633 } 2634 2635 /* Push the variable declaration to the top. It means that all 2636 * the variable declarations will appear in a funny 2637 * last-to-first order, but otherwise we run into trouble if a 2638 * function is prototyped, a global var is decled, then the 2639 * function is defined with usage of the global var. See 2640 * glslparsertest's CorrectModule.frag. 2641 */ 2642 instructions->push_head(var); 2643 instructions->append_list(&initializer_instructions); 2644 } 2645 2646 2647 /* Generally, variable declarations do not have r-values. However, 2648 * one is used for the declaration in 2649 * 2650 * while (bool b = some_condition()) { 2651 * ... 2652 * } 2653 * 2654 * so we return the rvalue from the last seen declaration here. 2655 */ 2656 return result; 2657} 2658 2659 2660ir_rvalue * 2661ast_parameter_declarator::hir(exec_list *instructions, 2662 struct _mesa_glsl_parse_state *state) 2663{ 2664 void *ctx = state; 2665 const struct glsl_type *type; 2666 const char *name = NULL; 2667 YYLTYPE loc = this->get_location(); 2668 2669 type = this->type->specifier->glsl_type(& name, state); 2670 2671 if (type == NULL) { 2672 if (name != NULL) { 2673 _mesa_glsl_error(& loc, state, 2674 "invalid type `%s' in declaration of `%s'", 2675 name, this->identifier); 2676 } else { 2677 _mesa_glsl_error(& loc, state, 2678 "invalid type in declaration of `%s'", 2679 this->identifier); 2680 } 2681 2682 type = glsl_type::error_type; 2683 } 2684 2685 /* From page 62 (page 68 of the PDF) of the GLSL 1.50 spec: 2686 * 2687 * "Functions that accept no input arguments need not use void in the 2688 * argument list because prototypes (or definitions) are required and 2689 * therefore there is no ambiguity when an empty argument list "( )" is 2690 * declared. The idiom "(void)" as a parameter list is provided for 2691 * convenience." 2692 * 2693 * Placing this check here prevents a void parameter being set up 2694 * for a function, which avoids tripping up checks for main taking 2695 * parameters and lookups of an unnamed symbol. 2696 */ 2697 if (type->is_void()) { 2698 if (this->identifier != NULL) 2699 _mesa_glsl_error(& loc, state, 2700 "named parameter cannot have type `void'"); 2701 2702 is_void = true; 2703 return NULL; 2704 } 2705 2706 if (formal_parameter && (this->identifier == NULL)) { 2707 _mesa_glsl_error(& loc, state, "formal parameter lacks a name"); 2708 return NULL; 2709 } 2710 2711 /* This only handles "vec4 foo[..]". The earlier specifier->glsl_type(...) 2712 * call already handled the "vec4[..] foo" case. 2713 */ 2714 if (this->is_array) { 2715 type = process_array_type(&loc, type, this->array_size, state); 2716 } 2717 2718 if (type->array_size() == 0) { 2719 _mesa_glsl_error(&loc, state, "arrays passed as parameters must have " 2720 "a declared size."); 2721 type = glsl_type::error_type; 2722 } 2723 2724 is_void = false; 2725 ir_variable *var = new(ctx) ir_variable(type, this->identifier, ir_var_in); 2726 2727 /* Apply any specified qualifiers to the parameter declaration. Note that 2728 * for function parameters the default mode is 'in'. 2729 */ 2730 apply_type_qualifier_to_variable(& this->type->qualifier, var, state, & loc); 2731 2732 instructions->push_tail(var); 2733 2734 /* Parameter declarations do not have r-values. 2735 */ 2736 return NULL; 2737} 2738 2739 2740void 2741ast_parameter_declarator::parameters_to_hir(exec_list *ast_parameters, 2742 bool formal, 2743 exec_list *ir_parameters, 2744 _mesa_glsl_parse_state *state) 2745{ 2746 ast_parameter_declarator *void_param = NULL; 2747 unsigned count = 0; 2748 2749 foreach_list_typed (ast_parameter_declarator, param, link, ast_parameters) { 2750 param->formal_parameter = formal; 2751 param->hir(ir_parameters, state); 2752 2753 if (param->is_void) 2754 void_param = param; 2755 2756 count++; 2757 } 2758 2759 if ((void_param != NULL) && (count > 1)) { 2760 YYLTYPE loc = void_param->get_location(); 2761 2762 _mesa_glsl_error(& loc, state, 2763 "`void' parameter must be only parameter"); 2764 } 2765} 2766 2767 2768void 2769emit_function(_mesa_glsl_parse_state *state, exec_list *instructions, 2770 ir_function *f) 2771{ 2772 /* Emit the new function header */ 2773 if (state->current_function == NULL) { 2774 instructions->push_tail(f); 2775 } else { 2776 /* IR invariants disallow function declarations or definitions nested 2777 * within other function definitions. Insert the new ir_function 2778 * block in the instruction sequence before the ir_function block 2779 * containing the current ir_function_signature. 2780 */ 2781 ir_function *const curr = 2782 const_cast<ir_function *>(state->current_function->function()); 2783 2784 curr->insert_before(f); 2785 } 2786} 2787 2788 2789ir_rvalue * 2790ast_function::hir(exec_list *instructions, 2791 struct _mesa_glsl_parse_state *state) 2792{ 2793 void *ctx = state; 2794 ir_function *f = NULL; 2795 ir_function_signature *sig = NULL; 2796 exec_list hir_parameters; 2797 2798 const char *const name = identifier; 2799 2800 /* From page 21 (page 27 of the PDF) of the GLSL 1.20 spec, 2801 * 2802 * "Function declarations (prototypes) cannot occur inside of functions; 2803 * they must be at global scope, or for the built-in functions, outside 2804 * the global scope." 2805 * 2806 * From page 27 (page 33 of the PDF) of the GLSL ES 1.00.16 spec, 2807 * 2808 * "User defined functions may only be defined within the global scope." 2809 * 2810 * Note that this language does not appear in GLSL 1.10. 2811 */ 2812 if ((state->current_function != NULL) && (state->language_version != 110)) { 2813 YYLTYPE loc = this->get_location(); 2814 _mesa_glsl_error(&loc, state, 2815 "declaration of function `%s' not allowed within " 2816 "function body", name); 2817 } 2818 2819 /* From page 15 (page 21 of the PDF) of the GLSL 1.10 spec, 2820 * 2821 * "Identifiers starting with "gl_" are reserved for use by 2822 * OpenGL, and may not be declared in a shader as either a 2823 * variable or a function." 2824 */ 2825 if (strncmp(name, "gl_", 3) == 0) { 2826 YYLTYPE loc = this->get_location(); 2827 _mesa_glsl_error(&loc, state, 2828 "identifier `%s' uses reserved `gl_' prefix", name); 2829 } 2830 2831 /* Convert the list of function parameters to HIR now so that they can be 2832 * used below to compare this function's signature with previously seen 2833 * signatures for functions with the same name. 2834 */ 2835 ast_parameter_declarator::parameters_to_hir(& this->parameters, 2836 is_definition, 2837 & hir_parameters, state); 2838 2839 const char *return_type_name; 2840 const glsl_type *return_type = 2841 this->return_type->specifier->glsl_type(& return_type_name, state); 2842 2843 if (!return_type) { 2844 YYLTYPE loc = this->get_location(); 2845 _mesa_glsl_error(&loc, state, 2846 "function `%s' has undeclared return type `%s'", 2847 name, return_type_name); 2848 return_type = glsl_type::error_type; 2849 } 2850 2851 /* From page 56 (page 62 of the PDF) of the GLSL 1.30 spec: 2852 * "No qualifier is allowed on the return type of a function." 2853 */ 2854 if (this->return_type->has_qualifiers()) { 2855 YYLTYPE loc = this->get_location(); 2856 _mesa_glsl_error(& loc, state, 2857 "function `%s' return type has qualifiers", name); 2858 } 2859 2860 /* Verify that this function's signature either doesn't match a previously 2861 * seen signature for a function with the same name, or, if a match is found, 2862 * that the previously seen signature does not have an associated definition. 2863 */ 2864 f = state->symbols->get_function(name); 2865 if (f != NULL && (state->es_shader || f->has_user_signature())) { 2866 sig = f->exact_matching_signature(&hir_parameters); 2867 if (sig != NULL) { 2868 const char *badvar = sig->qualifiers_match(&hir_parameters); 2869 if (badvar != NULL) { 2870 YYLTYPE loc = this->get_location(); 2871 2872 _mesa_glsl_error(&loc, state, "function `%s' parameter `%s' " 2873 "qualifiers don't match prototype", name, badvar); 2874 } 2875 2876 if (sig->return_type != return_type) { 2877 YYLTYPE loc = this->get_location(); 2878 2879 _mesa_glsl_error(&loc, state, "function `%s' return type doesn't " 2880 "match prototype", name); 2881 } 2882 2883 if (is_definition && sig->is_defined) { 2884 YYLTYPE loc = this->get_location(); 2885 2886 _mesa_glsl_error(& loc, state, "function `%s' redefined", name); 2887 } 2888 } 2889 } else { 2890 f = new(ctx) ir_function(name); 2891 if (!state->symbols->add_function(f)) { 2892 /* This function name shadows a non-function use of the same name. */ 2893 YYLTYPE loc = this->get_location(); 2894 2895 _mesa_glsl_error(&loc, state, "function name `%s' conflicts with " 2896 "non-function", name); 2897 return NULL; 2898 } 2899 2900 emit_function(state, instructions, f); 2901 } 2902 2903 /* Verify the return type of main() */ 2904 if (strcmp(name, "main") == 0) { 2905 if (! return_type->is_void()) { 2906 YYLTYPE loc = this->get_location(); 2907 2908 _mesa_glsl_error(& loc, state, "main() must return void"); 2909 } 2910 2911 if (!hir_parameters.is_empty()) { 2912 YYLTYPE loc = this->get_location(); 2913 2914 _mesa_glsl_error(& loc, state, "main() must not take any parameters"); 2915 } 2916 } 2917 2918 /* Finish storing the information about this new function in its signature. 2919 */ 2920 if (sig == NULL) { 2921 sig = new(ctx) ir_function_signature(return_type); 2922 f->add_signature(sig); 2923 } 2924 2925 sig->replace_parameters(&hir_parameters); 2926 signature = sig; 2927 2928 /* Function declarations (prototypes) do not have r-values. 2929 */ 2930 return NULL; 2931} 2932 2933 2934ir_rvalue * 2935ast_function_definition::hir(exec_list *instructions, 2936 struct _mesa_glsl_parse_state *state) 2937{ 2938 prototype->is_definition = true; 2939 prototype->hir(instructions, state); 2940 2941 ir_function_signature *signature = prototype->signature; 2942 if (signature == NULL) 2943 return NULL; 2944 2945 assert(state->current_function == NULL); 2946 state->current_function = signature; 2947 state->found_return = false; 2948 2949 /* Duplicate parameters declared in the prototype as concrete variables. 2950 * Add these to the symbol table. 2951 */ 2952 state->symbols->push_scope(); 2953 foreach_iter(exec_list_iterator, iter, signature->parameters) { 2954 ir_variable *const var = ((ir_instruction *) iter.get())->as_variable(); 2955 2956 assert(var != NULL); 2957 2958 /* The only way a parameter would "exist" is if two parameters have 2959 * the same name. 2960 */ 2961 if (state->symbols->name_declared_this_scope(var->name)) { 2962 YYLTYPE loc = this->get_location(); 2963 2964 _mesa_glsl_error(& loc, state, "parameter `%s' redeclared", var->name); 2965 } else { 2966 state->symbols->add_variable(var); 2967 } 2968 } 2969 2970 /* Convert the body of the function to HIR. */ 2971 this->body->hir(&signature->body, state); 2972 signature->is_defined = true; 2973 2974 state->symbols->pop_scope(); 2975 2976 assert(state->current_function == signature); 2977 state->current_function = NULL; 2978 2979 if (!signature->return_type->is_void() && !state->found_return) { 2980 YYLTYPE loc = this->get_location(); 2981 _mesa_glsl_error(& loc, state, "function `%s' has non-void return type " 2982 "%s, but no return statement", 2983 signature->function_name(), 2984 signature->return_type->name); 2985 } 2986 2987 /* Function definitions do not have r-values. 2988 */ 2989 return NULL; 2990} 2991 2992 2993ir_rvalue * 2994ast_jump_statement::hir(exec_list *instructions, 2995 struct _mesa_glsl_parse_state *state) 2996{ 2997 void *ctx = state; 2998 2999 switch (mode) { 3000 case ast_return: { 3001 ir_return *inst; 3002 assert(state->current_function); 3003 3004 if (opt_return_value) { 3005 if (state->current_function->return_type->base_type == 3006 GLSL_TYPE_VOID) { 3007 YYLTYPE loc = this->get_location(); 3008 3009 _mesa_glsl_error(& loc, state, 3010 "`return` with a value, in function `%s' " 3011 "returning void", 3012 state->current_function->function_name()); 3013 } 3014 3015 ir_rvalue *const ret = opt_return_value->hir(instructions, state); 3016 assert(ret != NULL); 3017 3018 /* Implicit conversions are not allowed for return values. */ 3019 if (state->current_function->return_type != ret->type) { 3020 YYLTYPE loc = this->get_location(); 3021 3022 _mesa_glsl_error(& loc, state, 3023 "`return' with wrong type %s, in function `%s' " 3024 "returning %s", 3025 ret->type->name, 3026 state->current_function->function_name(), 3027 state->current_function->return_type->name); 3028 } 3029 3030 inst = new(ctx) ir_return(ret); 3031 } else { 3032 if (state->current_function->return_type->base_type != 3033 GLSL_TYPE_VOID) { 3034 YYLTYPE loc = this->get_location(); 3035 3036 _mesa_glsl_error(& loc, state, 3037 "`return' with no value, in function %s returning " 3038 "non-void", 3039 state->current_function->function_name()); 3040 } 3041 inst = new(ctx) ir_return; 3042 } 3043 3044 state->found_return = true; 3045 instructions->push_tail(inst); 3046 break; 3047 } 3048 3049 case ast_discard: 3050 if (state->target != fragment_shader) { 3051 YYLTYPE loc = this->get_location(); 3052 3053 _mesa_glsl_error(& loc, state, 3054 "`discard' may only appear in a fragment shader"); 3055 } 3056 instructions->push_tail(new(ctx) ir_discard); 3057 break; 3058 3059 case ast_break: 3060 case ast_continue: 3061 /* FINISHME: Handle switch-statements. They cannot contain 'continue', 3062 * FINISHME: and they use a different IR instruction for 'break'. 3063 */ 3064 /* FINISHME: Correctly handle the nesting. If a switch-statement is 3065 * FINISHME: inside a loop, a 'continue' is valid and will bind to the 3066 * FINISHME: loop. 3067 */ 3068 if (state->loop_or_switch_nesting == NULL) { 3069 YYLTYPE loc = this->get_location(); 3070 3071 _mesa_glsl_error(& loc, state, 3072 "`%s' may only appear in a loop", 3073 (mode == ast_break) ? "break" : "continue"); 3074 } else { 3075 ir_loop *const loop = state->loop_or_switch_nesting->as_loop(); 3076 3077 /* Inline the for loop expression again, since we don't know 3078 * where near the end of the loop body the normal copy of it 3079 * is going to be placed. 3080 */ 3081 if (mode == ast_continue && 3082 state->loop_or_switch_nesting_ast->rest_expression) { 3083 state->loop_or_switch_nesting_ast->rest_expression->hir(instructions, 3084 state); 3085 } 3086 3087 if (loop != NULL) { 3088 ir_loop_jump *const jump = 3089 new(ctx) ir_loop_jump((mode == ast_break) 3090 ? ir_loop_jump::jump_break 3091 : ir_loop_jump::jump_continue); 3092 instructions->push_tail(jump); 3093 } 3094 } 3095 3096 break; 3097 } 3098 3099 /* Jump instructions do not have r-values. 3100 */ 3101 return NULL; 3102} 3103 3104 3105ir_rvalue * 3106ast_selection_statement::hir(exec_list *instructions, 3107 struct _mesa_glsl_parse_state *state) 3108{ 3109 void *ctx = state; 3110 3111 ir_rvalue *const condition = this->condition->hir(instructions, state); 3112 3113 /* From page 66 (page 72 of the PDF) of the GLSL 1.50 spec: 3114 * 3115 * "Any expression whose type evaluates to a Boolean can be used as the 3116 * conditional expression bool-expression. Vector types are not accepted 3117 * as the expression to if." 3118 * 3119 * The checks are separated so that higher quality diagnostics can be 3120 * generated for cases where both rules are violated. 3121 */ 3122 if (!condition->type->is_boolean() || !condition->type->is_scalar()) { 3123 YYLTYPE loc = this->condition->get_location(); 3124 3125 _mesa_glsl_error(& loc, state, "if-statement condition must be scalar " 3126 "boolean"); 3127 } 3128 3129 ir_if *const stmt = new(ctx) ir_if(condition); 3130 3131 if (then_statement != NULL) { 3132 state->symbols->push_scope(); 3133 then_statement->hir(& stmt->then_instructions, state); 3134 state->symbols->pop_scope(); 3135 } 3136 3137 if (else_statement != NULL) { 3138 state->symbols->push_scope(); 3139 else_statement->hir(& stmt->else_instructions, state); 3140 state->symbols->pop_scope(); 3141 } 3142 3143 instructions->push_tail(stmt); 3144 3145 /* if-statements do not have r-values. 3146 */ 3147 return NULL; 3148} 3149 3150 3151void 3152ast_iteration_statement::condition_to_hir(ir_loop *stmt, 3153 struct _mesa_glsl_parse_state *state) 3154{ 3155 void *ctx = state; 3156 3157 if (condition != NULL) { 3158 ir_rvalue *const cond = 3159 condition->hir(& stmt->body_instructions, state); 3160 3161 if ((cond == NULL) 3162 || !cond->type->is_boolean() || !cond->type->is_scalar()) { 3163 YYLTYPE loc = condition->get_location(); 3164 3165 _mesa_glsl_error(& loc, state, 3166 "loop condition must be scalar boolean"); 3167 } else { 3168 /* As the first code in the loop body, generate a block that looks 3169 * like 'if (!condition) break;' as the loop termination condition. 3170 */ 3171 ir_rvalue *const not_cond = 3172 new(ctx) ir_expression(ir_unop_logic_not, glsl_type::bool_type, cond, 3173 NULL); 3174 3175 ir_if *const if_stmt = new(ctx) ir_if(not_cond); 3176 3177 ir_jump *const break_stmt = 3178 new(ctx) ir_loop_jump(ir_loop_jump::jump_break); 3179 3180 if_stmt->then_instructions.push_tail(break_stmt); 3181 stmt->body_instructions.push_tail(if_stmt); 3182 } 3183 } 3184} 3185 3186 3187ir_rvalue * 3188ast_iteration_statement::hir(exec_list *instructions, 3189 struct _mesa_glsl_parse_state *state) 3190{ 3191 void *ctx = state; 3192 3193 /* For-loops and while-loops start a new scope, but do-while loops do not. 3194 */ 3195 if (mode != ast_do_while) 3196 state->symbols->push_scope(); 3197 3198 if (init_statement != NULL) 3199 init_statement->hir(instructions, state); 3200 3201 ir_loop *const stmt = new(ctx) ir_loop(); 3202 instructions->push_tail(stmt); 3203 3204 /* Track the current loop and / or switch-statement nesting. 3205 */ 3206 ir_instruction *const nesting = state->loop_or_switch_nesting; 3207 ast_iteration_statement *nesting_ast = state->loop_or_switch_nesting_ast; 3208 3209 state->loop_or_switch_nesting = stmt; 3210 state->loop_or_switch_nesting_ast = this; 3211 3212 if (mode != ast_do_while) 3213 condition_to_hir(stmt, state); 3214 3215 if (body != NULL) 3216 body->hir(& stmt->body_instructions, state); 3217 3218 if (rest_expression != NULL) 3219 rest_expression->hir(& stmt->body_instructions, state); 3220 3221 if (mode == ast_do_while) 3222 condition_to_hir(stmt, state); 3223 3224 if (mode != ast_do_while) 3225 state->symbols->pop_scope(); 3226 3227 /* Restore previous nesting before returning. 3228 */ 3229 state->loop_or_switch_nesting = nesting; 3230 state->loop_or_switch_nesting_ast = nesting_ast; 3231 3232 /* Loops do not have r-values. 3233 */ 3234 return NULL; 3235} 3236 3237 3238ir_rvalue * 3239ast_type_specifier::hir(exec_list *instructions, 3240 struct _mesa_glsl_parse_state *state) 3241{ 3242 if (!this->is_precision_statement && this->structure == NULL) 3243 return NULL; 3244 3245 YYLTYPE loc = this->get_location(); 3246 3247 if (this->precision != ast_precision_none 3248 && state->language_version != 100 3249 && state->language_version < 130) { 3250 _mesa_glsl_error(&loc, state, 3251 "precision qualifiers exist only in " 3252 "GLSL ES 1.00, and GLSL 1.30 and later"); 3253 return NULL; 3254 } 3255 if (this->precision != ast_precision_none 3256 && this->structure != NULL) { 3257 _mesa_glsl_error(&loc, state, 3258 "precision qualifiers do not apply to structures"); 3259 return NULL; 3260 } 3261 3262 /* If this is a precision statement, check that the type to which it is 3263 * applied is either float or int. 3264 * 3265 * From section 4.5.3 of the GLSL 1.30 spec: 3266 * "The precision statement 3267 * precision precision-qualifier type; 3268 * can be used to establish a default precision qualifier. The type 3269 * field can be either int or float [...]. Any other types or 3270 * qualifiers will result in an error. 3271 */ 3272 if (this->is_precision_statement) { 3273 assert(this->precision != ast_precision_none); 3274 assert(this->structure == NULL); /* The check for structures was 3275 * performed above. */ 3276 if (this->is_array) { 3277 _mesa_glsl_error(&loc, state, 3278 "default precision statements do not apply to " 3279 "arrays"); 3280 return NULL; 3281 } 3282 if (this->type_specifier != ast_float 3283 && this->type_specifier != ast_int) { 3284 _mesa_glsl_error(&loc, state, 3285 "default precision statements apply only to types " 3286 "float and int"); 3287 return NULL; 3288 } 3289 3290 /* FINISHME: Translate precision statements into IR. */ 3291 return NULL; 3292 } 3293 3294 if (this->structure != NULL) 3295 return this->structure->hir(instructions, state); 3296 3297 return NULL; 3298} 3299 3300 3301ir_rvalue * 3302ast_struct_specifier::hir(exec_list *instructions, 3303 struct _mesa_glsl_parse_state *state) 3304{ 3305 unsigned decl_count = 0; 3306 3307 /* Make an initial pass over the list of structure fields to determine how 3308 * many there are. Each element in this list is an ast_declarator_list. 3309 * This means that we actually need to count the number of elements in the 3310 * 'declarations' list in each of the elements. 3311 */ 3312 foreach_list_typed (ast_declarator_list, decl_list, link, 3313 &this->declarations) { 3314 foreach_list_const (decl_ptr, & decl_list->declarations) { 3315 decl_count++; 3316 } 3317 } 3318 3319 /* Allocate storage for the structure fields and process the field 3320 * declarations. As the declarations are processed, try to also convert 3321 * the types to HIR. This ensures that structure definitions embedded in 3322 * other structure definitions are processed. 3323 */ 3324 glsl_struct_field *const fields = talloc_array(state, glsl_struct_field, 3325 decl_count); 3326 3327 unsigned i = 0; 3328 foreach_list_typed (ast_declarator_list, decl_list, link, 3329 &this->declarations) { 3330 const char *type_name; 3331 3332 decl_list->type->specifier->hir(instructions, state); 3333 3334 /* Section 10.9 of the GLSL ES 1.00 specification states that 3335 * embedded structure definitions have been removed from the language. 3336 */ 3337 if (state->es_shader && decl_list->type->specifier->structure != NULL) { 3338 YYLTYPE loc = this->get_location(); 3339 _mesa_glsl_error(&loc, state, "Embedded structure definitions are " 3340 "not allowed in GLSL ES 1.00."); 3341 } 3342 3343 const glsl_type *decl_type = 3344 decl_list->type->specifier->glsl_type(& type_name, state); 3345 3346 foreach_list_typed (ast_declaration, decl, link, 3347 &decl_list->declarations) { 3348 const struct glsl_type *field_type = decl_type; 3349 if (decl->is_array) { 3350 YYLTYPE loc = decl->get_location(); 3351 field_type = process_array_type(&loc, decl_type, decl->array_size, 3352 state); 3353 } 3354 fields[i].type = (field_type != NULL) 3355 ? field_type : glsl_type::error_type; 3356 fields[i].name = decl->identifier; 3357 i++; 3358 } 3359 } 3360 3361 assert(i == decl_count); 3362 3363 const glsl_type *t = 3364 glsl_type::get_record_instance(fields, decl_count, this->name); 3365 3366 YYLTYPE loc = this->get_location(); 3367 if (!state->symbols->add_type(name, t)) { 3368 _mesa_glsl_error(& loc, state, "struct `%s' previously defined", name); 3369 } else { 3370 3371 const glsl_type **s = (const glsl_type **) 3372 realloc(state->user_structures, 3373 sizeof(state->user_structures[0]) * 3374 (state->num_user_structures + 1)); 3375 if (s != NULL) { 3376 s[state->num_user_structures] = t; 3377 state->user_structures = s; 3378 state->num_user_structures++; 3379 } 3380 } 3381 3382 /* Structure type definitions do not have r-values. 3383 */ 3384 return NULL; 3385} 3386