2 * Copyright © 2010 Intel Corporation
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:
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
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.
26 * Convert abstract syntax to to high-level intermediate reprensentation (HIR).
28 * During the conversion to HIR, the majority of the symantic checking is
29 * preformed on the program. This includes:
31 * * Symbol table management
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.
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.
48 * As a result, my preference is to put as little C code as possible in the
49 * parser (and lexer) sources.
52 #include "main/core.h" /* for struct gl_extensions */
53 #include "glsl_symbol_table.h"
54 #include "glsl_parser_extras.h"
56 #include "glsl_types.h"
57 #include "program/hash_table.h"
61 _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state)
63 _mesa_glsl_initialize_variables(instructions, state);
65 state->symbols->language_version = state->language_version;
67 state->current_function = NULL;
69 state->toplevel_ir = instructions;
71 /* Section 4.2 of the GLSL 1.20 specification states:
72 * "The built-in functions are scoped in a scope outside the global scope
73 * users declare global variables in. That is, a shader's global scope,
74 * available for user-defined functions and global variables, is nested
75 * inside the scope containing the built-in functions."
77 * Since built-in functions like ftransform() access built-in variables,
78 * it follows that those must be in the outer scope as well.
80 * We push scope here to create this nesting effect...but don't pop.
81 * This way, a shader's globals are still in the symbol table for use
84 state->symbols->push_scope();
86 foreach_list_typed (ast_node, ast, link, & state->translation_unit)
87 ast->hir(instructions, state);
89 detect_recursion_unlinked(state, instructions);
91 state->toplevel_ir = NULL;
96 * If a conversion is available, convert one operand to a different type
98 * The \c from \c ir_rvalue is converted "in place".
100 * \param to Type that the operand it to be converted to
101 * \param from Operand that is being converted
102 * \param state GLSL compiler state
105 * If a conversion is possible (or unnecessary), \c true is returned.
106 * Otherwise \c false is returned.
109 apply_implicit_conversion(const glsl_type *to, ir_rvalue * &from,
110 struct _mesa_glsl_parse_state *state)
113 if (to->base_type == from->type->base_type)
116 /* This conversion was added in GLSL 1.20. If the compilation mode is
117 * GLSL 1.10, the conversion is skipped.
119 if (state->language_version < 120)
122 /* From page 27 (page 33 of the PDF) of the GLSL 1.50 spec:
124 * "There are no implicit array or structure conversions. For
125 * example, an array of int cannot be implicitly converted to an
126 * array of float. There are no implicit conversions between
127 * signed and unsigned integers."
129 /* FINISHME: The above comment is partially a lie. There is int/uint
130 * FINISHME: conversion for immediate constants.
132 if (!to->is_float() || !from->type->is_numeric())
135 /* Convert to a floating point type with the same number of components
136 * as the original type - i.e. int to float, not int to vec4.
138 to = glsl_type::get_instance(GLSL_TYPE_FLOAT, from->type->vector_elements,
139 from->type->matrix_columns);
141 switch (from->type->base_type) {
143 from = new(ctx) ir_expression(ir_unop_i2f, to, from, NULL);
146 from = new(ctx) ir_expression(ir_unop_u2f, to, from, NULL);
149 from = new(ctx) ir_expression(ir_unop_b2f, to, from, NULL);
159 static const struct glsl_type *
160 arithmetic_result_type(ir_rvalue * &value_a, ir_rvalue * &value_b,
162 struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
164 const glsl_type *type_a = value_a->type;
165 const glsl_type *type_b = value_b->type;
167 /* From GLSL 1.50 spec, page 56:
169 * "The arithmetic binary operators add (+), subtract (-),
170 * multiply (*), and divide (/) operate on integer and
171 * floating-point scalars, vectors, and matrices."
173 if (!type_a->is_numeric() || !type_b->is_numeric()) {
174 _mesa_glsl_error(loc, state,
175 "Operands to arithmetic operators must be numeric");
176 return glsl_type::error_type;
180 /* "If one operand is floating-point based and the other is
181 * not, then the conversions from Section 4.1.10 "Implicit
182 * Conversions" are applied to the non-floating-point-based operand."
184 if (!apply_implicit_conversion(type_a, value_b, state)
185 && !apply_implicit_conversion(type_b, value_a, state)) {
186 _mesa_glsl_error(loc, state,
187 "Could not implicitly convert operands to "
188 "arithmetic operator");
189 return glsl_type::error_type;
191 type_a = value_a->type;
192 type_b = value_b->type;
194 /* "If the operands are integer types, they must both be signed or
197 * From this rule and the preceeding conversion it can be inferred that
198 * both types must be GLSL_TYPE_FLOAT, or GLSL_TYPE_UINT, or GLSL_TYPE_INT.
199 * The is_numeric check above already filtered out the case where either
200 * type is not one of these, so now the base types need only be tested for
203 if (type_a->base_type != type_b->base_type) {
204 _mesa_glsl_error(loc, state,
205 "base type mismatch for arithmetic operator");
206 return glsl_type::error_type;
209 /* "All arithmetic binary operators result in the same fundamental type
210 * (signed integer, unsigned integer, or floating-point) as the
211 * operands they operate on, after operand type conversion. After
212 * conversion, the following cases are valid
214 * * The two operands are scalars. In this case the operation is
215 * applied, resulting in a scalar."
217 if (type_a->is_scalar() && type_b->is_scalar())
220 /* "* One operand is a scalar, and the other is a vector or matrix.
221 * In this case, the scalar operation is applied independently to each
222 * component of the vector or matrix, resulting in the same size
225 if (type_a->is_scalar()) {
226 if (!type_b->is_scalar())
228 } else if (type_b->is_scalar()) {
232 /* All of the combinations of <scalar, scalar>, <vector, scalar>,
233 * <scalar, vector>, <scalar, matrix>, and <matrix, scalar> have been
236 assert(!type_a->is_scalar());
237 assert(!type_b->is_scalar());
239 /* "* The two operands are vectors of the same size. In this case, the
240 * operation is done component-wise resulting in the same size
243 if (type_a->is_vector() && type_b->is_vector()) {
244 if (type_a == type_b) {
247 _mesa_glsl_error(loc, state,
248 "vector size mismatch for arithmetic operator");
249 return glsl_type::error_type;
253 /* All of the combinations of <scalar, scalar>, <vector, scalar>,
254 * <scalar, vector>, <scalar, matrix>, <matrix, scalar>, and
255 * <vector, vector> have been handled. At least one of the operands must
256 * be matrix. Further, since there are no integer matrix types, the base
257 * type of both operands must be float.
259 assert(type_a->is_matrix() || type_b->is_matrix());
260 assert(type_a->base_type == GLSL_TYPE_FLOAT);
261 assert(type_b->base_type == GLSL_TYPE_FLOAT);
263 /* "* The operator is add (+), subtract (-), or divide (/), and the
264 * operands are matrices with the same number of rows and the same
265 * number of columns. In this case, the operation is done component-
266 * wise resulting in the same size matrix."
267 * * The operator is multiply (*), where both operands are matrices or
268 * one operand is a vector and the other a matrix. A right vector
269 * operand is treated as a column vector and a left vector operand as a
270 * row vector. In all these cases, it is required that the number of
271 * columns of the left operand is equal to the number of rows of the
272 * right operand. Then, the multiply (*) operation does a linear
273 * algebraic multiply, yielding an object that has the same number of
274 * rows as the left operand and the same number of columns as the right
275 * operand. Section 5.10 "Vector and Matrix Operations" explains in
276 * more detail how vectors and matrices are operated on."
279 if (type_a == type_b)
282 if (type_a->is_matrix() && type_b->is_matrix()) {
283 /* Matrix multiply. The columns of A must match the rows of B. Given
284 * the other previously tested constraints, this means the vector type
285 * of a row from A must be the same as the vector type of a column from
288 if (type_a->row_type() == type_b->column_type()) {
289 /* The resulting matrix has the number of columns of matrix B and
290 * the number of rows of matrix A. We get the row count of A by
291 * looking at the size of a vector that makes up a column. The
292 * transpose (size of a row) is done for B.
294 const glsl_type *const type =
295 glsl_type::get_instance(type_a->base_type,
296 type_a->column_type()->vector_elements,
297 type_b->row_type()->vector_elements);
298 assert(type != glsl_type::error_type);
302 } else if (type_a->is_matrix()) {
303 /* A is a matrix and B is a column vector. Columns of A must match
304 * rows of B. Given the other previously tested constraints, this
305 * means the vector type of a row from A must be the same as the
306 * vector the type of B.
308 if (type_a->row_type() == type_b) {
309 /* The resulting vector has a number of elements equal to
310 * the number of rows of matrix A. */
311 const glsl_type *const type =
312 glsl_type::get_instance(type_a->base_type,
313 type_a->column_type()->vector_elements,
315 assert(type != glsl_type::error_type);
320 assert(type_b->is_matrix());
322 /* A is a row vector and B is a matrix. Columns of A must match rows
323 * of B. Given the other previously tested constraints, this means
324 * the type of A must be the same as the vector type of a column from
327 if (type_a == type_b->column_type()) {
328 /* The resulting vector has a number of elements equal to
329 * the number of columns of matrix B. */
330 const glsl_type *const type =
331 glsl_type::get_instance(type_a->base_type,
332 type_b->row_type()->vector_elements,
334 assert(type != glsl_type::error_type);
340 _mesa_glsl_error(loc, state, "size mismatch for matrix multiplication");
341 return glsl_type::error_type;
345 /* "All other cases are illegal."
347 _mesa_glsl_error(loc, state, "type mismatch");
348 return glsl_type::error_type;
352 static const struct glsl_type *
353 unary_arithmetic_result_type(const struct glsl_type *type,
354 struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
356 /* From GLSL 1.50 spec, page 57:
358 * "The arithmetic unary operators negate (-), post- and pre-increment
359 * and decrement (-- and ++) operate on integer or floating-point
360 * values (including vectors and matrices). All unary operators work
361 * component-wise on their operands. These result with the same type
364 if (!type->is_numeric()) {
365 _mesa_glsl_error(loc, state,
366 "Operands to arithmetic operators must be numeric");
367 return glsl_type::error_type;
374 * \brief Return the result type of a bit-logic operation.
376 * If the given types to the bit-logic operator are invalid, return
377 * glsl_type::error_type.
379 * \param type_a Type of LHS of bit-logic op
380 * \param type_b Type of RHS of bit-logic op
382 static const struct glsl_type *
383 bit_logic_result_type(const struct glsl_type *type_a,
384 const struct glsl_type *type_b,
386 struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
388 if (state->language_version < 130) {
389 _mesa_glsl_error(loc, state, "bit operations require GLSL 1.30");
390 return glsl_type::error_type;
393 /* From page 50 (page 56 of PDF) of GLSL 1.30 spec:
395 * "The bitwise operators and (&), exclusive-or (^), and inclusive-or
396 * (|). The operands must be of type signed or unsigned integers or
399 if (!type_a->is_integer()) {
400 _mesa_glsl_error(loc, state, "LHS of `%s' must be an integer",
401 ast_expression::operator_string(op));
402 return glsl_type::error_type;
404 if (!type_b->is_integer()) {
405 _mesa_glsl_error(loc, state, "RHS of `%s' must be an integer",
406 ast_expression::operator_string(op));
407 return glsl_type::error_type;
410 /* "The fundamental types of the operands (signed or unsigned) must
413 if (type_a->base_type != type_b->base_type) {
414 _mesa_glsl_error(loc, state, "operands of `%s' must have the same "
415 "base type", ast_expression::operator_string(op));
416 return glsl_type::error_type;
419 /* "The operands cannot be vectors of differing size." */
420 if (type_a->is_vector() &&
421 type_b->is_vector() &&
422 type_a->vector_elements != type_b->vector_elements) {
423 _mesa_glsl_error(loc, state, "operands of `%s' cannot be vectors of "
424 "different sizes", ast_expression::operator_string(op));
425 return glsl_type::error_type;
428 /* "If one operand is a scalar and the other a vector, the scalar is
429 * applied component-wise to the vector, resulting in the same type as
430 * the vector. The fundamental types of the operands [...] will be the
431 * resulting fundamental type."
433 if (type_a->is_scalar())
439 static const struct glsl_type *
440 modulus_result_type(const struct glsl_type *type_a,
441 const struct glsl_type *type_b,
442 struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
444 if (state->language_version < 130) {
445 _mesa_glsl_error(loc, state,
446 "operator '%%' is reserved in %s",
447 state->version_string);
448 return glsl_type::error_type;
451 /* From GLSL 1.50 spec, page 56:
452 * "The operator modulus (%) operates on signed or unsigned integers or
453 * integer vectors. The operand types must both be signed or both be
456 if (!type_a->is_integer()) {
457 _mesa_glsl_error(loc, state, "LHS of operator %% must be an integer.");
458 return glsl_type::error_type;
460 if (!type_b->is_integer()) {
461 _mesa_glsl_error(loc, state, "RHS of operator %% must be an integer.");
462 return glsl_type::error_type;
464 if (type_a->base_type != type_b->base_type) {
465 _mesa_glsl_error(loc, state,
466 "operands of %% must have the same base type");
467 return glsl_type::error_type;
470 /* "The operands cannot be vectors of differing size. If one operand is
471 * a scalar and the other vector, then the scalar is applied component-
472 * wise to the vector, resulting in the same type as the vector. If both
473 * are vectors of the same size, the result is computed component-wise."
475 if (type_a->is_vector()) {
476 if (!type_b->is_vector()
477 || (type_a->vector_elements == type_b->vector_elements))
482 /* "The operator modulus (%) is not defined for any other data types
483 * (non-integer types)."
485 _mesa_glsl_error(loc, state, "type mismatch");
486 return glsl_type::error_type;
490 static const struct glsl_type *
491 relational_result_type(ir_rvalue * &value_a, ir_rvalue * &value_b,
492 struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
494 const glsl_type *type_a = value_a->type;
495 const glsl_type *type_b = value_b->type;
497 /* From GLSL 1.50 spec, page 56:
498 * "The relational operators greater than (>), less than (<), greater
499 * than or equal (>=), and less than or equal (<=) operate only on
500 * scalar integer and scalar floating-point expressions."
502 if (!type_a->is_numeric()
503 || !type_b->is_numeric()
504 || !type_a->is_scalar()
505 || !type_b->is_scalar()) {
506 _mesa_glsl_error(loc, state,
507 "Operands to relational operators must be scalar and "
509 return glsl_type::error_type;
512 /* "Either the operands' types must match, or the conversions from
513 * Section 4.1.10 "Implicit Conversions" will be applied to the integer
514 * operand, after which the types must match."
516 if (!apply_implicit_conversion(type_a, value_b, state)
517 && !apply_implicit_conversion(type_b, value_a, state)) {
518 _mesa_glsl_error(loc, state,
519 "Could not implicitly convert operands to "
520 "relational operator");
521 return glsl_type::error_type;
523 type_a = value_a->type;
524 type_b = value_b->type;
526 if (type_a->base_type != type_b->base_type) {
527 _mesa_glsl_error(loc, state, "base type mismatch");
528 return glsl_type::error_type;
531 /* "The result is scalar Boolean."
533 return glsl_type::bool_type;
537 * \brief Return the result type of a bit-shift operation.
539 * If the given types to the bit-shift operator are invalid, return
540 * glsl_type::error_type.
542 * \param type_a Type of LHS of bit-shift op
543 * \param type_b Type of RHS of bit-shift op
545 static const struct glsl_type *
546 shift_result_type(const struct glsl_type *type_a,
547 const struct glsl_type *type_b,
549 struct _mesa_glsl_parse_state *state, YYLTYPE *loc)
551 if (state->language_version < 130) {
552 _mesa_glsl_error(loc, state, "bit operations require GLSL 1.30");
553 return glsl_type::error_type;
556 /* From page 50 (page 56 of the PDF) of the GLSL 1.30 spec:
558 * "The shift operators (<<) and (>>). For both operators, the operands
559 * must be signed or unsigned integers or integer vectors. One operand
560 * can be signed while the other is unsigned."
562 if (!type_a->is_integer()) {
563 _mesa_glsl_error(loc, state, "LHS of operator %s must be an integer or "
564 "integer vector", ast_expression::operator_string(op));
565 return glsl_type::error_type;
568 if (!type_b->is_integer()) {
569 _mesa_glsl_error(loc, state, "RHS of operator %s must be an integer or "
570 "integer vector", ast_expression::operator_string(op));
571 return glsl_type::error_type;
574 /* "If the first operand is a scalar, the second operand has to be
577 if (type_a->is_scalar() && !type_b->is_scalar()) {
578 _mesa_glsl_error(loc, state, "If the first operand of %s is scalar, the "
579 "second must be scalar as well",
580 ast_expression::operator_string(op));
581 return glsl_type::error_type;
584 /* If both operands are vectors, check that they have same number of
587 if (type_a->is_vector() &&
588 type_b->is_vector() &&
589 type_a->vector_elements != type_b->vector_elements) {
590 _mesa_glsl_error(loc, state, "Vector operands to operator %s must "
591 "have same number of elements",
592 ast_expression::operator_string(op));
593 return glsl_type::error_type;
596 /* "In all cases, the resulting type will be the same type as the left
603 * Validates that a value can be assigned to a location with a specified type
605 * Validates that \c rhs can be assigned to some location. If the types are
606 * not an exact match but an automatic conversion is possible, \c rhs will be
610 * \c NULL if \c rhs cannot be assigned to a location with type \c lhs_type.
611 * Otherwise the actual RHS to be assigned will be returned. This may be
612 * \c rhs, or it may be \c rhs after some type conversion.
615 * In addition to being used for assignments, this function is used to
616 * type-check return values.
619 validate_assignment(struct _mesa_glsl_parse_state *state,
620 const glsl_type *lhs_type, ir_rvalue *rhs,
623 /* If there is already some error in the RHS, just return it. Anything
624 * else will lead to an avalanche of error message back to the user.
626 if (rhs->type->is_error())
629 /* If the types are identical, the assignment can trivially proceed.
631 if (rhs->type == lhs_type)
634 /* If the array element types are the same and the size of the LHS is zero,
635 * the assignment is okay for initializers embedded in variable
638 * Note: Whole-array assignments are not permitted in GLSL 1.10, but this
639 * is handled by ir_dereference::is_lvalue.
641 if (is_initializer && lhs_type->is_array() && rhs->type->is_array()
642 && (lhs_type->element_type() == rhs->type->element_type())
643 && (lhs_type->array_size() == 0)) {
647 /* Check for implicit conversion in GLSL 1.20 */
648 if (apply_implicit_conversion(lhs_type, rhs, state)) {
649 if (rhs->type == lhs_type)
657 mark_whole_array_access(ir_rvalue *access)
659 ir_dereference_variable *deref = access->as_dereference_variable();
661 if (deref && deref->var) {
662 deref->var->max_array_access = deref->type->length - 1;
667 do_assignment(exec_list *instructions, struct _mesa_glsl_parse_state *state,
668 const char *non_lvalue_description,
669 ir_rvalue *lhs, ir_rvalue *rhs, bool is_initializer,
673 bool error_emitted = (lhs->type->is_error() || rhs->type->is_error());
675 if (!error_emitted) {
676 if (non_lvalue_description != NULL) {
677 _mesa_glsl_error(&lhs_loc, state,
679 non_lvalue_description);
680 error_emitted = true;
681 } else if (lhs->variable_referenced() != NULL
682 && lhs->variable_referenced()->read_only) {
683 _mesa_glsl_error(&lhs_loc, state,
684 "assignment to read-only variable '%s'",
685 lhs->variable_referenced()->name);
686 error_emitted = true;
688 } else if (state->language_version <= 110 && lhs->type->is_array()) {
689 /* From page 32 (page 38 of the PDF) of the GLSL 1.10 spec:
691 * "Other binary or unary expressions, non-dereferenced
692 * arrays, function names, swizzles with repeated fields,
693 * and constants cannot be l-values."
695 _mesa_glsl_error(&lhs_loc, state, "whole array assignment is not "
696 "allowed in GLSL 1.10 or GLSL ES 1.00.");
697 error_emitted = true;
698 } else if (!lhs->is_lvalue()) {
699 _mesa_glsl_error(& lhs_loc, state, "non-lvalue in assignment");
700 error_emitted = true;
705 validate_assignment(state, lhs->type, rhs, is_initializer);
706 if (new_rhs == NULL) {
707 _mesa_glsl_error(& lhs_loc, state, "type mismatch");
711 /* If the LHS array was not declared with a size, it takes it size from
712 * the RHS. If the LHS is an l-value and a whole array, it must be a
713 * dereference of a variable. Any other case would require that the LHS
714 * is either not an l-value or not a whole array.
716 if (lhs->type->array_size() == 0) {
717 ir_dereference *const d = lhs->as_dereference();
721 ir_variable *const var = d->variable_referenced();
725 if (var->max_array_access >= unsigned(rhs->type->array_size())) {
726 /* FINISHME: This should actually log the location of the RHS. */
727 _mesa_glsl_error(& lhs_loc, state, "array size must be > %u due to "
729 var->max_array_access);
732 var->type = glsl_type::get_array_instance(lhs->type->element_type(),
733 rhs->type->array_size());
736 mark_whole_array_access(rhs);
737 mark_whole_array_access(lhs);
740 /* Most callers of do_assignment (assign, add_assign, pre_inc/dec,
741 * but not post_inc) need the converted assigned value as an rvalue
742 * to handle things like:
746 * So we always just store the computed value being assigned to a
747 * temporary and return a deref of that temporary. If the rvalue
748 * ends up not being used, the temp will get copy-propagated out.
750 ir_variable *var = new(ctx) ir_variable(rhs->type, "assignment_tmp",
752 ir_dereference_variable *deref_var = new(ctx) ir_dereference_variable(var);
753 instructions->push_tail(var);
754 instructions->push_tail(new(ctx) ir_assignment(deref_var,
757 deref_var = new(ctx) ir_dereference_variable(var);
760 instructions->push_tail(new(ctx) ir_assignment(lhs, deref_var, NULL));
762 return new(ctx) ir_dereference_variable(var);
766 get_lvalue_copy(exec_list *instructions, ir_rvalue *lvalue)
768 void *ctx = ralloc_parent(lvalue);
771 var = new(ctx) ir_variable(lvalue->type, "_post_incdec_tmp",
773 instructions->push_tail(var);
774 var->mode = ir_var_auto;
776 instructions->push_tail(new(ctx) ir_assignment(new(ctx) ir_dereference_variable(var),
779 return new(ctx) ir_dereference_variable(var);
784 ast_node::hir(exec_list *instructions,
785 struct _mesa_glsl_parse_state *state)
794 do_comparison(void *mem_ctx, int operation, ir_rvalue *op0, ir_rvalue *op1)
797 ir_rvalue *cmp = NULL;
799 if (operation == ir_binop_all_equal)
800 join_op = ir_binop_logic_and;
802 join_op = ir_binop_logic_or;
804 switch (op0->type->base_type) {
805 case GLSL_TYPE_FLOAT:
809 return new(mem_ctx) ir_expression(operation, op0, op1);
811 case GLSL_TYPE_ARRAY: {
812 for (unsigned int i = 0; i < op0->type->length; i++) {
813 ir_rvalue *e0, *e1, *result;
815 e0 = new(mem_ctx) ir_dereference_array(op0->clone(mem_ctx, NULL),
816 new(mem_ctx) ir_constant(i));
817 e1 = new(mem_ctx) ir_dereference_array(op1->clone(mem_ctx, NULL),
818 new(mem_ctx) ir_constant(i));
819 result = do_comparison(mem_ctx, operation, e0, e1);
822 cmp = new(mem_ctx) ir_expression(join_op, cmp, result);
828 mark_whole_array_access(op0);
829 mark_whole_array_access(op1);
833 case GLSL_TYPE_STRUCT: {
834 for (unsigned int i = 0; i < op0->type->length; i++) {
835 ir_rvalue *e0, *e1, *result;
836 const char *field_name = op0->type->fields.structure[i].name;
838 e0 = new(mem_ctx) ir_dereference_record(op0->clone(mem_ctx, NULL),
840 e1 = new(mem_ctx) ir_dereference_record(op1->clone(mem_ctx, NULL),
842 result = do_comparison(mem_ctx, operation, e0, e1);
845 cmp = new(mem_ctx) ir_expression(join_op, cmp, result);
853 case GLSL_TYPE_ERROR:
855 case GLSL_TYPE_SAMPLER:
856 /* I assume a comparison of a struct containing a sampler just
857 * ignores the sampler present in the type.
862 assert(!"Should not get here.");
867 cmp = new(mem_ctx) ir_constant(true);
872 /* For logical operations, we want to ensure that the operands are
873 * scalar booleans. If it isn't, emit an error and return a constant
874 * boolean to avoid triggering cascading error messages.
877 get_scalar_boolean_operand(exec_list *instructions,
878 struct _mesa_glsl_parse_state *state,
879 ast_expression *parent_expr,
881 const char *operand_name,
884 ast_expression *expr = parent_expr->subexpressions[operand];
886 ir_rvalue *val = expr->hir(instructions, state);
888 if (val->type->is_boolean() && val->type->is_scalar())
891 if (!*error_emitted) {
892 YYLTYPE loc = expr->get_location();
893 _mesa_glsl_error(&loc, state, "%s of `%s' must be scalar boolean",
895 parent_expr->operator_string(parent_expr->oper));
896 *error_emitted = true;
899 return new(ctx) ir_constant(true);
903 * If name refers to a builtin array whose maximum allowed size is less than
904 * size, report an error and return true. Otherwise return false.
907 check_builtin_array_max_size(const char *name, unsigned size,
908 YYLTYPE loc, struct _mesa_glsl_parse_state *state)
910 if ((strcmp("gl_TexCoord", name) == 0)
911 && (size > state->Const.MaxTextureCoords)) {
912 /* From page 54 (page 60 of the PDF) of the GLSL 1.20 spec:
914 * "The size [of gl_TexCoord] can be at most
915 * gl_MaxTextureCoords."
917 _mesa_glsl_error(&loc, state, "`gl_TexCoord' array size cannot "
918 "be larger than gl_MaxTextureCoords (%u)\n",
919 state->Const.MaxTextureCoords);
921 } else if (strcmp("gl_ClipDistance", name) == 0
922 && size > state->Const.MaxClipPlanes) {
923 /* From section 7.1 (Vertex Shader Special Variables) of the
926 * "The gl_ClipDistance array is predeclared as unsized and
927 * must be sized by the shader either redeclaring it with a
928 * size or indexing it only with integral constant
929 * expressions. ... The size can be at most
930 * gl_MaxClipDistances."
932 _mesa_glsl_error(&loc, state, "`gl_ClipDistance' array size cannot "
933 "be larger than gl_MaxClipDistances (%u)\n",
934 state->Const.MaxClipPlanes);
941 * Create the constant 1, of a which is appropriate for incrementing and
942 * decrementing values of the given GLSL type. For example, if type is vec4,
943 * this creates a constant value of 1.0 having type float.
945 * If the given type is invalid for increment and decrement operators, return
946 * a floating point 1--the error will be detected later.
949 constant_one_for_inc_dec(void *ctx, const glsl_type *type)
951 switch (type->base_type) {
953 return new(ctx) ir_constant((unsigned) 1);
955 return new(ctx) ir_constant(1);
957 case GLSL_TYPE_FLOAT:
958 return new(ctx) ir_constant(1.0f);
963 ast_expression::hir(exec_list *instructions,
964 struct _mesa_glsl_parse_state *state)
967 static const int operations[AST_NUM_OPERATORS] = {
968 -1, /* ast_assign doesn't convert to ir_expression. */
969 -1, /* ast_plus doesn't convert to ir_expression. */
993 /* Note: The following block of expression types actually convert
994 * to multiple IR instructions.
996 ir_binop_mul, /* ast_mul_assign */
997 ir_binop_div, /* ast_div_assign */
998 ir_binop_mod, /* ast_mod_assign */
999 ir_binop_add, /* ast_add_assign */
1000 ir_binop_sub, /* ast_sub_assign */
1001 ir_binop_lshift, /* ast_ls_assign */
1002 ir_binop_rshift, /* ast_rs_assign */
1003 ir_binop_bit_and, /* ast_and_assign */
1004 ir_binop_bit_xor, /* ast_xor_assign */
1005 ir_binop_bit_or, /* ast_or_assign */
1007 -1, /* ast_conditional doesn't convert to ir_expression. */
1008 ir_binop_add, /* ast_pre_inc. */
1009 ir_binop_sub, /* ast_pre_dec. */
1010 ir_binop_add, /* ast_post_inc. */
1011 ir_binop_sub, /* ast_post_dec. */
1012 -1, /* ast_field_selection doesn't conv to ir_expression. */
1013 -1, /* ast_array_index doesn't convert to ir_expression. */
1014 -1, /* ast_function_call doesn't conv to ir_expression. */
1015 -1, /* ast_identifier doesn't convert to ir_expression. */
1016 -1, /* ast_int_constant doesn't convert to ir_expression. */
1017 -1, /* ast_uint_constant doesn't conv to ir_expression. */
1018 -1, /* ast_float_constant doesn't conv to ir_expression. */
1019 -1, /* ast_bool_constant doesn't conv to ir_expression. */
1020 -1, /* ast_sequence doesn't convert to ir_expression. */
1022 ir_rvalue *result = NULL;
1024 const struct glsl_type *type; /* a temporary variable for switch cases */
1025 bool error_emitted = false;
1028 loc = this->get_location();
1030 switch (this->oper) {
1032 op[0] = this->subexpressions[0]->hir(instructions, state);
1033 op[1] = this->subexpressions[1]->hir(instructions, state);
1035 result = do_assignment(instructions, state,
1036 this->subexpressions[0]->non_lvalue_description,
1037 op[0], op[1], false,
1038 this->subexpressions[0]->get_location());
1039 error_emitted = result->type->is_error();
1044 op[0] = this->subexpressions[0]->hir(instructions, state);
1046 type = unary_arithmetic_result_type(op[0]->type, state, & loc);
1048 error_emitted = type->is_error();
1054 op[0] = this->subexpressions[0]->hir(instructions, state);
1056 type = unary_arithmetic_result_type(op[0]->type, state, & loc);
1058 error_emitted = type->is_error();
1060 result = new(ctx) ir_expression(operations[this->oper], type,
1068 op[0] = this->subexpressions[0]->hir(instructions, state);
1069 op[1] = this->subexpressions[1]->hir(instructions, state);
1071 type = arithmetic_result_type(op[0], op[1],
1072 (this->oper == ast_mul),
1074 error_emitted = type->is_error();
1076 result = new(ctx) ir_expression(operations[this->oper], type,
1081 op[0] = this->subexpressions[0]->hir(instructions, state);
1082 op[1] = this->subexpressions[1]->hir(instructions, state);
1084 type = modulus_result_type(op[0]->type, op[1]->type, state, & loc);
1086 assert(operations[this->oper] == ir_binop_mod);
1088 result = new(ctx) ir_expression(operations[this->oper], type,
1090 error_emitted = type->is_error();
1095 if (state->language_version < 130) {
1096 _mesa_glsl_error(&loc, state, "operator %s requires GLSL 1.30",
1097 operator_string(this->oper));
1098 error_emitted = true;
1101 op[0] = this->subexpressions[0]->hir(instructions, state);
1102 op[1] = this->subexpressions[1]->hir(instructions, state);
1103 type = shift_result_type(op[0]->type, op[1]->type, this->oper, state,
1105 result = new(ctx) ir_expression(operations[this->oper], type,
1107 error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1114 op[0] = this->subexpressions[0]->hir(instructions, state);
1115 op[1] = this->subexpressions[1]->hir(instructions, state);
1117 type = relational_result_type(op[0], op[1], state, & loc);
1119 /* The relational operators must either generate an error or result
1120 * in a scalar boolean. See page 57 of the GLSL 1.50 spec.
1122 assert(type->is_error()
1123 || ((type->base_type == GLSL_TYPE_BOOL)
1124 && type->is_scalar()));
1126 result = new(ctx) ir_expression(operations[this->oper], type,
1128 error_emitted = type->is_error();
1133 op[0] = this->subexpressions[0]->hir(instructions, state);
1134 op[1] = this->subexpressions[1]->hir(instructions, state);
1136 /* From page 58 (page 64 of the PDF) of the GLSL 1.50 spec:
1138 * "The equality operators equal (==), and not equal (!=)
1139 * operate on all types. They result in a scalar Boolean. If
1140 * the operand types do not match, then there must be a
1141 * conversion from Section 4.1.10 "Implicit Conversions"
1142 * applied to one operand that can make them match, in which
1143 * case this conversion is done."
1145 if ((!apply_implicit_conversion(op[0]->type, op[1], state)
1146 && !apply_implicit_conversion(op[1]->type, op[0], state))
1147 || (op[0]->type != op[1]->type)) {
1148 _mesa_glsl_error(& loc, state, "operands of `%s' must have the same "
1149 "type", (this->oper == ast_equal) ? "==" : "!=");
1150 error_emitted = true;
1151 } else if ((state->language_version <= 110)
1152 && (op[0]->type->is_array() || op[1]->type->is_array())) {
1153 _mesa_glsl_error(& loc, state, "array comparisons forbidden in "
1155 error_emitted = true;
1158 if (error_emitted) {
1159 result = new(ctx) ir_constant(false);
1161 result = do_comparison(ctx, operations[this->oper], op[0], op[1]);
1162 assert(result->type == glsl_type::bool_type);
1169 op[0] = this->subexpressions[0]->hir(instructions, state);
1170 op[1] = this->subexpressions[1]->hir(instructions, state);
1171 type = bit_logic_result_type(op[0]->type, op[1]->type, this->oper,
1173 result = new(ctx) ir_expression(operations[this->oper], type,
1175 error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1179 op[0] = this->subexpressions[0]->hir(instructions, state);
1181 if (state->language_version < 130) {
1182 _mesa_glsl_error(&loc, state, "bit-wise operations require GLSL 1.30");
1183 error_emitted = true;
1186 if (!op[0]->type->is_integer()) {
1187 _mesa_glsl_error(&loc, state, "operand of `~' must be an integer");
1188 error_emitted = true;
1191 type = error_emitted ? glsl_type::error_type : op[0]->type;
1192 result = new(ctx) ir_expression(ir_unop_bit_not, type, op[0], NULL);
1195 case ast_logic_and: {
1196 exec_list rhs_instructions;
1197 op[0] = get_scalar_boolean_operand(instructions, state, this, 0,
1198 "LHS", &error_emitted);
1199 op[1] = get_scalar_boolean_operand(&rhs_instructions, state, this, 1,
1200 "RHS", &error_emitted);
1202 if (rhs_instructions.is_empty()) {
1203 result = new(ctx) ir_expression(ir_binop_logic_and, op[0], op[1]);
1204 type = result->type;
1206 ir_variable *const tmp = new(ctx) ir_variable(glsl_type::bool_type,
1209 instructions->push_tail(tmp);
1211 ir_if *const stmt = new(ctx) ir_if(op[0]);
1212 instructions->push_tail(stmt);
1214 stmt->then_instructions.append_list(&rhs_instructions);
1215 ir_dereference *const then_deref = new(ctx) ir_dereference_variable(tmp);
1216 ir_assignment *const then_assign =
1217 new(ctx) ir_assignment(then_deref, op[1], NULL);
1218 stmt->then_instructions.push_tail(then_assign);
1220 ir_dereference *const else_deref = new(ctx) ir_dereference_variable(tmp);
1221 ir_assignment *const else_assign =
1222 new(ctx) ir_assignment(else_deref, new(ctx) ir_constant(false), NULL);
1223 stmt->else_instructions.push_tail(else_assign);
1225 result = new(ctx) ir_dereference_variable(tmp);
1231 case ast_logic_or: {
1232 exec_list rhs_instructions;
1233 op[0] = get_scalar_boolean_operand(instructions, state, this, 0,
1234 "LHS", &error_emitted);
1235 op[1] = get_scalar_boolean_operand(&rhs_instructions, state, this, 1,
1236 "RHS", &error_emitted);
1238 if (rhs_instructions.is_empty()) {
1239 result = new(ctx) ir_expression(ir_binop_logic_or, op[0], op[1]);
1240 type = result->type;
1242 ir_variable *const tmp = new(ctx) ir_variable(glsl_type::bool_type,
1245 instructions->push_tail(tmp);
1247 ir_if *const stmt = new(ctx) ir_if(op[0]);
1248 instructions->push_tail(stmt);
1250 ir_dereference *const then_deref = new(ctx) ir_dereference_variable(tmp);
1251 ir_assignment *const then_assign =
1252 new(ctx) ir_assignment(then_deref, new(ctx) ir_constant(true), NULL);
1253 stmt->then_instructions.push_tail(then_assign);
1255 stmt->else_instructions.append_list(&rhs_instructions);
1256 ir_dereference *const else_deref = new(ctx) ir_dereference_variable(tmp);
1257 ir_assignment *const else_assign =
1258 new(ctx) ir_assignment(else_deref, op[1], NULL);
1259 stmt->else_instructions.push_tail(else_assign);
1261 result = new(ctx) ir_dereference_variable(tmp);
1268 /* From page 33 (page 39 of the PDF) of the GLSL 1.10 spec:
1270 * "The logical binary operators and (&&), or ( | | ), and
1271 * exclusive or (^^). They operate only on two Boolean
1272 * expressions and result in a Boolean expression."
1274 op[0] = get_scalar_boolean_operand(instructions, state, this, 0, "LHS",
1276 op[1] = get_scalar_boolean_operand(instructions, state, this, 1, "RHS",
1279 result = new(ctx) ir_expression(operations[this->oper], glsl_type::bool_type,
1284 op[0] = get_scalar_boolean_operand(instructions, state, this, 0,
1285 "operand", &error_emitted);
1287 result = new(ctx) ir_expression(operations[this->oper], glsl_type::bool_type,
1291 case ast_mul_assign:
1292 case ast_div_assign:
1293 case ast_add_assign:
1294 case ast_sub_assign: {
1295 op[0] = this->subexpressions[0]->hir(instructions, state);
1296 op[1] = this->subexpressions[1]->hir(instructions, state);
1298 type = arithmetic_result_type(op[0], op[1],
1299 (this->oper == ast_mul_assign),
1302 ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper], type,
1305 result = do_assignment(instructions, state,
1306 this->subexpressions[0]->non_lvalue_description,
1307 op[0]->clone(ctx, NULL), temp_rhs, false,
1308 this->subexpressions[0]->get_location());
1309 error_emitted = (op[0]->type->is_error());
1311 /* GLSL 1.10 does not allow array assignment. However, we don't have to
1312 * explicitly test for this because none of the binary expression
1313 * operators allow array operands either.
1319 case ast_mod_assign: {
1320 op[0] = this->subexpressions[0]->hir(instructions, state);
1321 op[1] = this->subexpressions[1]->hir(instructions, state);
1323 type = modulus_result_type(op[0]->type, op[1]->type, state, & loc);
1325 assert(operations[this->oper] == ir_binop_mod);
1327 ir_rvalue *temp_rhs;
1328 temp_rhs = new(ctx) ir_expression(operations[this->oper], type,
1331 result = do_assignment(instructions, state,
1332 this->subexpressions[0]->non_lvalue_description,
1333 op[0]->clone(ctx, NULL), temp_rhs, false,
1334 this->subexpressions[0]->get_location());
1335 error_emitted = type->is_error();
1340 case ast_rs_assign: {
1341 op[0] = this->subexpressions[0]->hir(instructions, state);
1342 op[1] = this->subexpressions[1]->hir(instructions, state);
1343 type = shift_result_type(op[0]->type, op[1]->type, this->oper, state,
1345 ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper],
1346 type, op[0], op[1]);
1347 result = do_assignment(instructions, state,
1348 this->subexpressions[0]->non_lvalue_description,
1349 op[0]->clone(ctx, NULL), temp_rhs, false,
1350 this->subexpressions[0]->get_location());
1351 error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1355 case ast_and_assign:
1356 case ast_xor_assign:
1357 case ast_or_assign: {
1358 op[0] = this->subexpressions[0]->hir(instructions, state);
1359 op[1] = this->subexpressions[1]->hir(instructions, state);
1360 type = bit_logic_result_type(op[0]->type, op[1]->type, this->oper,
1362 ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper],
1363 type, op[0], op[1]);
1364 result = do_assignment(instructions, state,
1365 this->subexpressions[0]->non_lvalue_description,
1366 op[0]->clone(ctx, NULL), temp_rhs, false,
1367 this->subexpressions[0]->get_location());
1368 error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1372 case ast_conditional: {
1373 /* From page 59 (page 65 of the PDF) of the GLSL 1.50 spec:
1375 * "The ternary selection operator (?:). It operates on three
1376 * expressions (exp1 ? exp2 : exp3). This operator evaluates the
1377 * first expression, which must result in a scalar Boolean."
1379 op[0] = get_scalar_boolean_operand(instructions, state, this, 0,
1380 "condition", &error_emitted);
1382 /* The :? operator is implemented by generating an anonymous temporary
1383 * followed by an if-statement. The last instruction in each branch of
1384 * the if-statement assigns a value to the anonymous temporary. This
1385 * temporary is the r-value of the expression.
1387 exec_list then_instructions;
1388 exec_list else_instructions;
1390 op[1] = this->subexpressions[1]->hir(&then_instructions, state);
1391 op[2] = this->subexpressions[2]->hir(&else_instructions, state);
1393 /* From page 59 (page 65 of the PDF) of the GLSL 1.50 spec:
1395 * "The second and third expressions can be any type, as
1396 * long their types match, or there is a conversion in
1397 * Section 4.1.10 "Implicit Conversions" that can be applied
1398 * to one of the expressions to make their types match. This
1399 * resulting matching type is the type of the entire
1402 if ((!apply_implicit_conversion(op[1]->type, op[2], state)
1403 && !apply_implicit_conversion(op[2]->type, op[1], state))
1404 || (op[1]->type != op[2]->type)) {
1405 YYLTYPE loc = this->subexpressions[1]->get_location();
1407 _mesa_glsl_error(& loc, state, "Second and third operands of ?: "
1408 "operator must have matching types.");
1409 error_emitted = true;
1410 type = glsl_type::error_type;
1415 /* From page 33 (page 39 of the PDF) of the GLSL 1.10 spec:
1417 * "The second and third expressions must be the same type, but can
1418 * be of any type other than an array."
1420 if ((state->language_version <= 110) && type->is_array()) {
1421 _mesa_glsl_error(& loc, state, "Second and third operands of ?: "
1422 "operator must not be arrays.");
1423 error_emitted = true;
1426 ir_constant *cond_val = op[0]->constant_expression_value();
1427 ir_constant *then_val = op[1]->constant_expression_value();
1428 ir_constant *else_val = op[2]->constant_expression_value();
1430 if (then_instructions.is_empty()
1431 && else_instructions.is_empty()
1432 && (cond_val != NULL) && (then_val != NULL) && (else_val != NULL)) {
1433 result = (cond_val->value.b[0]) ? then_val : else_val;
1435 ir_variable *const tmp =
1436 new(ctx) ir_variable(type, "conditional_tmp", ir_var_temporary);
1437 instructions->push_tail(tmp);
1439 ir_if *const stmt = new(ctx) ir_if(op[0]);
1440 instructions->push_tail(stmt);
1442 then_instructions.move_nodes_to(& stmt->then_instructions);
1443 ir_dereference *const then_deref =
1444 new(ctx) ir_dereference_variable(tmp);
1445 ir_assignment *const then_assign =
1446 new(ctx) ir_assignment(then_deref, op[1], NULL);
1447 stmt->then_instructions.push_tail(then_assign);
1449 else_instructions.move_nodes_to(& stmt->else_instructions);
1450 ir_dereference *const else_deref =
1451 new(ctx) ir_dereference_variable(tmp);
1452 ir_assignment *const else_assign =
1453 new(ctx) ir_assignment(else_deref, op[2], NULL);
1454 stmt->else_instructions.push_tail(else_assign);
1456 result = new(ctx) ir_dereference_variable(tmp);
1463 this->non_lvalue_description = (this->oper == ast_pre_inc)
1464 ? "pre-increment operation" : "pre-decrement operation";
1466 op[0] = this->subexpressions[0]->hir(instructions, state);
1467 op[1] = constant_one_for_inc_dec(ctx, op[0]->type);
1469 type = arithmetic_result_type(op[0], op[1], false, state, & loc);
1471 ir_rvalue *temp_rhs;
1472 temp_rhs = new(ctx) ir_expression(operations[this->oper], type,
1475 result = do_assignment(instructions, state,
1476 this->subexpressions[0]->non_lvalue_description,
1477 op[0]->clone(ctx, NULL), temp_rhs, false,
1478 this->subexpressions[0]->get_location());
1479 error_emitted = op[0]->type->is_error();
1484 case ast_post_dec: {
1485 this->non_lvalue_description = (this->oper == ast_post_inc)
1486 ? "post-increment operation" : "post-decrement operation";
1487 op[0] = this->subexpressions[0]->hir(instructions, state);
1488 op[1] = constant_one_for_inc_dec(ctx, op[0]->type);
1490 error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1492 type = arithmetic_result_type(op[0], op[1], false, state, & loc);
1494 ir_rvalue *temp_rhs;
1495 temp_rhs = new(ctx) ir_expression(operations[this->oper], type,
1498 /* Get a temporary of a copy of the lvalue before it's modified.
1499 * This may get thrown away later.
1501 result = get_lvalue_copy(instructions, op[0]->clone(ctx, NULL));
1503 (void)do_assignment(instructions, state,
1504 this->subexpressions[0]->non_lvalue_description,
1505 op[0]->clone(ctx, NULL), temp_rhs, false,
1506 this->subexpressions[0]->get_location());
1508 error_emitted = op[0]->type->is_error();
1512 case ast_field_selection:
1513 result = _mesa_ast_field_selection_to_hir(this, instructions, state);
1516 case ast_array_index: {
1517 YYLTYPE index_loc = subexpressions[1]->get_location();
1519 op[0] = subexpressions[0]->hir(instructions, state);
1520 op[1] = subexpressions[1]->hir(instructions, state);
1522 error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
1524 ir_rvalue *const array = op[0];
1526 result = new(ctx) ir_dereference_array(op[0], op[1]);
1528 /* Do not use op[0] after this point. Use array.
1536 if (!array->type->is_array()
1537 && !array->type->is_matrix()
1538 && !array->type->is_vector()) {
1539 _mesa_glsl_error(& index_loc, state,
1540 "cannot dereference non-array / non-matrix / "
1542 error_emitted = true;
1545 if (!op[1]->type->is_integer()) {
1546 _mesa_glsl_error(& index_loc, state,
1547 "array index must be integer type");
1548 error_emitted = true;
1549 } else if (!op[1]->type->is_scalar()) {
1550 _mesa_glsl_error(& index_loc, state,
1551 "array index must be scalar");
1552 error_emitted = true;
1555 /* If the array index is a constant expression and the array has a
1556 * declared size, ensure that the access is in-bounds. If the array
1557 * index is not a constant expression, ensure that the array has a
1560 ir_constant *const const_index = op[1]->constant_expression_value();
1561 if (const_index != NULL) {
1562 const int idx = const_index->value.i[0];
1563 const char *type_name;
1566 if (array->type->is_matrix()) {
1567 type_name = "matrix";
1568 } else if (array->type->is_vector()) {
1569 type_name = "vector";
1571 type_name = "array";
1574 /* From page 24 (page 30 of the PDF) of the GLSL 1.50 spec:
1576 * "It is illegal to declare an array with a size, and then
1577 * later (in the same shader) index the same array with an
1578 * integral constant expression greater than or equal to the
1579 * declared size. It is also illegal to index an array with a
1580 * negative constant expression."
1582 if (array->type->is_matrix()) {
1583 if (array->type->row_type()->vector_elements <= idx) {
1584 bound = array->type->row_type()->vector_elements;
1586 } else if (array->type->is_vector()) {
1587 if (array->type->vector_elements <= idx) {
1588 bound = array->type->vector_elements;
1591 if ((array->type->array_size() > 0)
1592 && (array->type->array_size() <= idx)) {
1593 bound = array->type->array_size();
1598 _mesa_glsl_error(& loc, state, "%s index must be < %u",
1600 error_emitted = true;
1601 } else if (idx < 0) {
1602 _mesa_glsl_error(& loc, state, "%s index must be >= 0",
1604 error_emitted = true;
1607 if (array->type->is_array()) {
1608 /* If the array is a variable dereference, it dereferences the
1609 * whole array, by definition. Use this to get the variable.
1611 * FINISHME: Should some methods for getting / setting / testing
1612 * FINISHME: array access limits be added to ir_dereference?
1614 ir_variable *const v = array->whole_variable_referenced();
1615 if ((v != NULL) && (unsigned(idx) > v->max_array_access)) {
1616 v->max_array_access = idx;
1618 /* Check whether this access will, as a side effect, implicitly
1619 * cause the size of a built-in array to be too large.
1621 if (check_builtin_array_max_size(v->name, idx+1, loc, state))
1622 error_emitted = true;
1625 } else if (array->type->array_size() == 0) {
1626 _mesa_glsl_error(&loc, state, "unsized array index must be constant");
1628 if (array->type->is_array()) {
1629 /* whole_variable_referenced can return NULL if the array is a
1630 * member of a structure. In this case it is safe to not update
1631 * the max_array_access field because it is never used for fields
1634 ir_variable *v = array->whole_variable_referenced();
1636 v->max_array_access = array->type->array_size() - 1;
1640 /* From page 23 (29 of the PDF) of the GLSL 1.30 spec:
1642 * "Samplers aggregated into arrays within a shader (using square
1643 * brackets [ ]) can only be indexed with integral constant
1644 * expressions [...]."
1646 * This restriction was added in GLSL 1.30. Shaders using earlier version
1647 * of the language should not be rejected by the compiler front-end for
1648 * using this construct. This allows useful things such as using a loop
1649 * counter as the index to an array of samplers. If the loop in unrolled,
1650 * the code should compile correctly. Instead, emit a warning.
1652 if (array->type->is_array() &&
1653 array->type->element_type()->is_sampler() &&
1654 const_index == NULL) {
1656 if (state->language_version == 100) {
1657 _mesa_glsl_warning(&loc, state,
1658 "sampler arrays indexed with non-constant "
1659 "expressions is optional in GLSL ES 1.00");
1660 } else if (state->language_version < 130) {
1661 _mesa_glsl_warning(&loc, state,
1662 "sampler arrays indexed with non-constant "
1663 "expressions is forbidden in GLSL 1.30 and "
1666 _mesa_glsl_error(&loc, state,
1667 "sampler arrays indexed with non-constant "
1668 "expressions is forbidden in GLSL 1.30 and "
1670 error_emitted = true;
1675 result->type = glsl_type::error_type;
1680 case ast_function_call:
1681 /* Should *NEVER* get here. ast_function_call should always be handled
1682 * by ast_function_expression::hir.
1687 case ast_identifier: {
1688 /* ast_identifier can appear several places in a full abstract syntax
1689 * tree. This particular use must be at location specified in the grammar
1690 * as 'variable_identifier'.
1693 state->symbols->get_variable(this->primary_expression.identifier);
1697 result = new(ctx) ir_dereference_variable(var);
1699 _mesa_glsl_error(& loc, state, "`%s' undeclared",
1700 this->primary_expression.identifier);
1702 result = ir_call::get_error_instruction(ctx);
1703 error_emitted = true;
1708 case ast_int_constant:
1709 result = new(ctx) ir_constant(this->primary_expression.int_constant);
1712 case ast_uint_constant:
1713 result = new(ctx) ir_constant(this->primary_expression.uint_constant);
1716 case ast_float_constant:
1717 result = new(ctx) ir_constant(this->primary_expression.float_constant);
1720 case ast_bool_constant:
1721 result = new(ctx) ir_constant(bool(this->primary_expression.bool_constant));
1724 case ast_sequence: {
1725 /* It should not be possible to generate a sequence in the AST without
1726 * any expressions in it.
1728 assert(!this->expressions.is_empty());
1730 /* The r-value of a sequence is the last expression in the sequence. If
1731 * the other expressions in the sequence do not have side-effects (and
1732 * therefore add instructions to the instruction list), they get dropped
1735 exec_node *previous_tail_pred = NULL;
1736 YYLTYPE previous_operand_loc = loc;
1738 foreach_list_typed (ast_node, ast, link, &this->expressions) {
1739 /* If one of the operands of comma operator does not generate any
1740 * code, we want to emit a warning. At each pass through the loop
1741 * previous_tail_pred will point to the last instruction in the
1742 * stream *before* processing the previous operand. Naturally,
1743 * instructions->tail_pred will point to the last instruction in the
1744 * stream *after* processing the previous operand. If the two
1745 * pointers match, then the previous operand had no effect.
1747 * The warning behavior here differs slightly from GCC. GCC will
1748 * only emit a warning if none of the left-hand operands have an
1749 * effect. However, it will emit a warning for each. I believe that
1750 * there are some cases in C (especially with GCC extensions) where
1751 * it is useful to have an intermediate step in a sequence have no
1752 * effect, but I don't think these cases exist in GLSL. Either way,
1753 * it would be a giant hassle to replicate that behavior.
1755 if (previous_tail_pred == instructions->tail_pred) {
1756 _mesa_glsl_warning(&previous_operand_loc, state,
1757 "left-hand operand of comma expression has "
1761 /* tail_pred is directly accessed instead of using the get_tail()
1762 * method for performance reasons. get_tail() has extra code to
1763 * return NULL when the list is empty. We don't care about that
1764 * here, so using tail_pred directly is fine.
1766 previous_tail_pred = instructions->tail_pred;
1767 previous_operand_loc = ast->get_location();
1769 result = ast->hir(instructions, state);
1772 /* Any errors should have already been emitted in the loop above.
1774 error_emitted = true;
1778 type = NULL; /* use result->type, not type. */
1779 assert(result != NULL);
1781 if (result->type->is_error() && !error_emitted)
1782 _mesa_glsl_error(& loc, state, "type mismatch");
1789 ast_expression_statement::hir(exec_list *instructions,
1790 struct _mesa_glsl_parse_state *state)
1792 /* It is possible to have expression statements that don't have an
1793 * expression. This is the solitary semicolon:
1795 * for (i = 0; i < 5; i++)
1798 * In this case the expression will be NULL. Test for NULL and don't do
1799 * anything in that case.
1801 if (expression != NULL)
1802 expression->hir(instructions, state);
1804 /* Statements do not have r-values.
1811 ast_compound_statement::hir(exec_list *instructions,
1812 struct _mesa_glsl_parse_state *state)
1815 state->symbols->push_scope();
1817 foreach_list_typed (ast_node, ast, link, &this->statements)
1818 ast->hir(instructions, state);
1821 state->symbols->pop_scope();
1823 /* Compound statements do not have r-values.
1829 static const glsl_type *
1830 process_array_type(YYLTYPE *loc, const glsl_type *base, ast_node *array_size,
1831 struct _mesa_glsl_parse_state *state)
1833 unsigned length = 0;
1835 /* From page 19 (page 25) of the GLSL 1.20 spec:
1837 * "Only one-dimensional arrays may be declared."
1839 if (base->is_array()) {
1840 _mesa_glsl_error(loc, state,
1841 "invalid array of `%s' (only one-dimensional arrays "
1844 return glsl_type::error_type;
1847 if (array_size != NULL) {
1848 exec_list dummy_instructions;
1849 ir_rvalue *const ir = array_size->hir(& dummy_instructions, state);
1850 YYLTYPE loc = array_size->get_location();
1853 if (!ir->type->is_integer()) {
1854 _mesa_glsl_error(& loc, state, "array size must be integer type");
1855 } else if (!ir->type->is_scalar()) {
1856 _mesa_glsl_error(& loc, state, "array size must be scalar type");
1858 ir_constant *const size = ir->constant_expression_value();
1861 _mesa_glsl_error(& loc, state, "array size must be a "
1862 "constant valued expression");
1863 } else if (size->value.i[0] <= 0) {
1864 _mesa_glsl_error(& loc, state, "array size must be > 0");
1866 assert(size->type == ir->type);
1867 length = size->value.u[0];
1869 /* If the array size is const (and we've verified that
1870 * it is) then no instructions should have been emitted
1871 * when we converted it to HIR. If they were emitted,
1872 * then either the array size isn't const after all, or
1873 * we are emitting unnecessary instructions.
1875 assert(dummy_instructions.is_empty());
1879 } else if (state->es_shader) {
1880 /* Section 10.17 of the GLSL ES 1.00 specification states that unsized
1881 * array declarations have been removed from the language.
1883 _mesa_glsl_error(loc, state, "unsized array declarations are not "
1884 "allowed in GLSL ES 1.00.");
1887 return glsl_type::get_array_instance(base, length);
1892 ast_type_specifier::glsl_type(const char **name,
1893 struct _mesa_glsl_parse_state *state) const
1895 const struct glsl_type *type;
1897 type = state->symbols->get_type(this->type_name);
1898 *name = this->type_name;
1900 if (this->is_array) {
1901 YYLTYPE loc = this->get_location();
1902 type = process_array_type(&loc, type, this->array_size, state);
1910 apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual,
1912 struct _mesa_glsl_parse_state *state,
1915 if (qual->flags.q.invariant) {
1917 _mesa_glsl_error(loc, state,
1918 "variable `%s' may not be redeclared "
1919 "`invariant' after being used",
1926 if (qual->flags.q.constant || qual->flags.q.attribute
1927 || qual->flags.q.uniform
1928 || (qual->flags.q.varying && (state->target == fragment_shader)))
1931 if (qual->flags.q.centroid)
1934 if (qual->flags.q.attribute && state->target != vertex_shader) {
1935 var->type = glsl_type::error_type;
1936 _mesa_glsl_error(loc, state,
1937 "`attribute' variables may not be declared in the "
1939 _mesa_glsl_shader_target_name(state->target));
1942 /* From page 25 (page 31 of the PDF) of the GLSL 1.10 spec:
1944 * "The varying qualifier can be used only with the data types
1945 * float, vec2, vec3, vec4, mat2, mat3, and mat4, or arrays of
1948 if (qual->flags.q.varying) {
1949 const glsl_type *non_array_type;
1951 if (var->type && var->type->is_array())
1952 non_array_type = var->type->fields.array;
1954 non_array_type = var->type;
1956 if (non_array_type && non_array_type->base_type != GLSL_TYPE_FLOAT) {
1957 var->type = glsl_type::error_type;
1958 _mesa_glsl_error(loc, state,
1959 "varying variables must be of base type float");
1963 /* If there is no qualifier that changes the mode of the variable, leave
1964 * the setting alone.
1966 if (qual->flags.q.in && qual->flags.q.out)
1967 var->mode = ir_var_inout;
1968 else if (qual->flags.q.attribute || qual->flags.q.in
1969 || (qual->flags.q.varying && (state->target == fragment_shader)))
1970 var->mode = ir_var_in;
1971 else if (qual->flags.q.out
1972 || (qual->flags.q.varying && (state->target == vertex_shader)))
1973 var->mode = ir_var_out;
1974 else if (qual->flags.q.uniform)
1975 var->mode = ir_var_uniform;
1977 if (state->all_invariant && (state->current_function == NULL)) {
1978 switch (state->target) {
1980 if (var->mode == ir_var_out)
1981 var->invariant = true;
1983 case geometry_shader:
1984 if ((var->mode == ir_var_in) || (var->mode == ir_var_out))
1985 var->invariant = true;
1987 case fragment_shader:
1988 if (var->mode == ir_var_in)
1989 var->invariant = true;
1994 if (qual->flags.q.flat)
1995 var->interpolation = INTERP_QUALIFIER_FLAT;
1996 else if (qual->flags.q.noperspective)
1997 var->interpolation = INTERP_QUALIFIER_NOPERSPECTIVE;
1998 else if (qual->flags.q.smooth)
1999 var->interpolation = INTERP_QUALIFIER_SMOOTH;
2001 var->interpolation = INTERP_QUALIFIER_NONE;
2003 if (var->interpolation != INTERP_QUALIFIER_NONE &&
2004 !(state->target == vertex_shader && var->mode == ir_var_out) &&
2005 !(state->target == fragment_shader && var->mode == ir_var_in)) {
2006 const char *qual_string = NULL;
2007 switch (var->interpolation) {
2008 case INTERP_QUALIFIER_FLAT:
2009 qual_string = "flat";
2011 case INTERP_QUALIFIER_NOPERSPECTIVE:
2012 qual_string = "noperspective";
2014 case INTERP_QUALIFIER_SMOOTH:
2015 qual_string = "smooth";
2019 _mesa_glsl_error(loc, state,
2020 "interpolation qualifier `%s' can only be applied to "
2021 "vertex shader outputs and fragment shader inputs.",
2026 var->pixel_center_integer = qual->flags.q.pixel_center_integer;
2027 var->origin_upper_left = qual->flags.q.origin_upper_left;
2028 if ((qual->flags.q.origin_upper_left || qual->flags.q.pixel_center_integer)
2029 && (strcmp(var->name, "gl_FragCoord") != 0)) {
2030 const char *const qual_string = (qual->flags.q.origin_upper_left)
2031 ? "origin_upper_left" : "pixel_center_integer";
2033 _mesa_glsl_error(loc, state,
2034 "layout qualifier `%s' can only be applied to "
2035 "fragment shader input `gl_FragCoord'",
2039 if (qual->flags.q.explicit_location) {
2040 const bool global_scope = (state->current_function == NULL);
2042 const char *string = "";
2044 /* In the vertex shader only shader inputs can be given explicit
2047 * In the fragment shader only shader outputs can be given explicit
2050 switch (state->target) {
2052 if (!global_scope || (var->mode != ir_var_in)) {
2058 case geometry_shader:
2059 _mesa_glsl_error(loc, state,
2060 "geometry shader variables cannot be given "
2061 "explicit locations\n");
2064 case fragment_shader:
2065 if (!global_scope || (var->mode != ir_var_out)) {
2073 _mesa_glsl_error(loc, state,
2074 "only %s shader %s variables can be given an "
2075 "explicit location\n",
2076 _mesa_glsl_shader_target_name(state->target),
2079 var->explicit_location = true;
2081 /* This bit of silliness is needed because invalid explicit locations
2082 * are supposed to be flagged during linking. Small negative values
2083 * biased by VERT_ATTRIB_GENERIC0 or FRAG_RESULT_DATA0 could alias
2084 * built-in values (e.g., -16+VERT_ATTRIB_GENERIC0 = VERT_ATTRIB_POS).
2085 * The linker needs to be able to differentiate these cases. This
2086 * ensures that negative values stay negative.
2088 if (qual->location >= 0) {
2089 var->location = (state->target == vertex_shader)
2090 ? (qual->location + VERT_ATTRIB_GENERIC0)
2091 : (qual->location + FRAG_RESULT_DATA0);
2093 var->location = qual->location;
2098 /* Does the declaration use the 'layout' keyword?
2100 const bool uses_layout = qual->flags.q.pixel_center_integer
2101 || qual->flags.q.origin_upper_left
2102 || qual->flags.q.explicit_location;
2104 /* Does the declaration use the deprecated 'attribute' or 'varying'
2107 const bool uses_deprecated_qualifier = qual->flags.q.attribute
2108 || qual->flags.q.varying;
2110 /* Is the 'layout' keyword used with parameters that allow relaxed checking.
2111 * Many implementations of GL_ARB_fragment_coord_conventions_enable and some
2112 * implementations (only Mesa?) GL_ARB_explicit_attrib_location_enable
2113 * allowed the layout qualifier to be used with 'varying' and 'attribute'.
2114 * These extensions and all following extensions that add the 'layout'
2115 * keyword have been modified to require the use of 'in' or 'out'.
2117 * The following extension do not allow the deprecated keywords:
2119 * GL_AMD_conservative_depth
2120 * GL_ARB_conservative_depth
2121 * GL_ARB_gpu_shader5
2122 * GL_ARB_separate_shader_objects
2123 * GL_ARB_tesselation_shader
2124 * GL_ARB_transform_feedback3
2125 * GL_ARB_uniform_buffer_object
2127 * It is unknown whether GL_EXT_shader_image_load_store or GL_NV_gpu_shader5
2128 * allow layout with the deprecated keywords.
2130 const bool relaxed_layout_qualifier_checking =
2131 state->ARB_fragment_coord_conventions_enable;
2133 if (uses_layout && uses_deprecated_qualifier) {
2134 if (relaxed_layout_qualifier_checking) {
2135 _mesa_glsl_warning(loc, state,
2136 "`layout' qualifier may not be used with "
2137 "`attribute' or `varying'");
2139 _mesa_glsl_error(loc, state,
2140 "`layout' qualifier may not be used with "
2141 "`attribute' or `varying'");
2145 /* Layout qualifiers for gl_FragDepth, which are enabled by extension
2146 * AMD_conservative_depth.
2148 int depth_layout_count = qual->flags.q.depth_any
2149 + qual->flags.q.depth_greater
2150 + qual->flags.q.depth_less
2151 + qual->flags.q.depth_unchanged;
2152 if (depth_layout_count > 0
2153 && !state->AMD_conservative_depth_enable
2154 && !state->ARB_conservative_depth_enable) {
2155 _mesa_glsl_error(loc, state,
2156 "extension GL_AMD_conservative_depth or "
2157 "GL_ARB_conservative_depth must be enabled "
2158 "to use depth layout qualifiers");
2159 } else if (depth_layout_count > 0
2160 && strcmp(var->name, "gl_FragDepth") != 0) {
2161 _mesa_glsl_error(loc, state,
2162 "depth layout qualifiers can be applied only to "
2164 } else if (depth_layout_count > 1
2165 && strcmp(var->name, "gl_FragDepth") == 0) {
2166 _mesa_glsl_error(loc, state,
2167 "at most one depth layout qualifier can be applied to "
2170 if (qual->flags.q.depth_any)
2171 var->depth_layout = ir_depth_layout_any;
2172 else if (qual->flags.q.depth_greater)
2173 var->depth_layout = ir_depth_layout_greater;
2174 else if (qual->flags.q.depth_less)
2175 var->depth_layout = ir_depth_layout_less;
2176 else if (qual->flags.q.depth_unchanged)
2177 var->depth_layout = ir_depth_layout_unchanged;
2179 var->depth_layout = ir_depth_layout_none;
2183 * Get the variable that is being redeclared by this declaration
2185 * Semantic checks to verify the validity of the redeclaration are also
2186 * performed. If semantic checks fail, compilation error will be emitted via
2187 * \c _mesa_glsl_error, but a non-\c NULL pointer will still be returned.
2190 * A pointer to an existing variable in the current scope if the declaration
2191 * is a redeclaration, \c NULL otherwise.
2194 get_variable_being_redeclared(ir_variable *var, ast_declaration *decl,
2195 struct _mesa_glsl_parse_state *state)
2197 /* Check if this declaration is actually a re-declaration, either to
2198 * resize an array or add qualifiers to an existing variable.
2200 * This is allowed for variables in the current scope, or when at
2201 * global scope (for built-ins in the implicit outer scope).
2203 ir_variable *earlier = state->symbols->get_variable(decl->identifier);
2204 if (earlier == NULL ||
2205 (state->current_function != NULL &&
2206 !state->symbols->name_declared_this_scope(decl->identifier))) {
2211 YYLTYPE loc = decl->get_location();
2213 /* From page 24 (page 30 of the PDF) of the GLSL 1.50 spec,
2215 * "It is legal to declare an array without a size and then
2216 * later re-declare the same name as an array of the same
2217 * type and specify a size."
2219 if ((earlier->type->array_size() == 0)
2220 && var->type->is_array()
2221 && (var->type->element_type() == earlier->type->element_type())) {
2222 /* FINISHME: This doesn't match the qualifiers on the two
2223 * FINISHME: declarations. It's not 100% clear whether this is
2224 * FINISHME: required or not.
2227 const unsigned size = unsigned(var->type->array_size());
2228 check_builtin_array_max_size(var->name, size, loc, state);
2229 if ((size > 0) && (size <= earlier->max_array_access)) {
2230 _mesa_glsl_error(& loc, state, "array size must be > %u due to "
2232 earlier->max_array_access);
2235 earlier->type = var->type;
2238 } else if (state->ARB_fragment_coord_conventions_enable
2239 && strcmp(var->name, "gl_FragCoord") == 0
2240 && earlier->type == var->type
2241 && earlier->mode == var->mode) {
2242 /* Allow redeclaration of gl_FragCoord for ARB_fcc layout
2245 earlier->origin_upper_left = var->origin_upper_left;
2246 earlier->pixel_center_integer = var->pixel_center_integer;
2248 /* According to section 4.3.7 of the GLSL 1.30 spec,
2249 * the following built-in varaibles can be redeclared with an
2250 * interpolation qualifier:
2253 * * gl_FrontSecondaryColor
2254 * * gl_BackSecondaryColor
2256 * * gl_SecondaryColor
2258 } else if (state->language_version >= 130
2259 && (strcmp(var->name, "gl_FrontColor") == 0
2260 || strcmp(var->name, "gl_BackColor") == 0
2261 || strcmp(var->name, "gl_FrontSecondaryColor") == 0
2262 || strcmp(var->name, "gl_BackSecondaryColor") == 0
2263 || strcmp(var->name, "gl_Color") == 0
2264 || strcmp(var->name, "gl_SecondaryColor") == 0)
2265 && earlier->type == var->type
2266 && earlier->mode == var->mode) {
2267 earlier->interpolation = var->interpolation;
2269 /* Layout qualifiers for gl_FragDepth. */
2270 } else if ((state->AMD_conservative_depth_enable ||
2271 state->ARB_conservative_depth_enable)
2272 && strcmp(var->name, "gl_FragDepth") == 0
2273 && earlier->type == var->type
2274 && earlier->mode == var->mode) {
2276 /** From the AMD_conservative_depth spec:
2277 * Within any shader, the first redeclarations of gl_FragDepth
2278 * must appear before any use of gl_FragDepth.
2280 if (earlier->used) {
2281 _mesa_glsl_error(&loc, state,
2282 "the first redeclaration of gl_FragDepth "
2283 "must appear before any use of gl_FragDepth");
2286 /* Prevent inconsistent redeclaration of depth layout qualifier. */
2287 if (earlier->depth_layout != ir_depth_layout_none
2288 && earlier->depth_layout != var->depth_layout) {
2289 _mesa_glsl_error(&loc, state,
2290 "gl_FragDepth: depth layout is declared here "
2291 "as '%s, but it was previously declared as "
2293 depth_layout_string(var->depth_layout),
2294 depth_layout_string(earlier->depth_layout));
2297 earlier->depth_layout = var->depth_layout;
2300 _mesa_glsl_error(&loc, state, "`%s' redeclared", decl->identifier);
2307 * Generate the IR for an initializer in a variable declaration
2310 process_initializer(ir_variable *var, ast_declaration *decl,
2311 ast_fully_specified_type *type,
2312 exec_list *initializer_instructions,
2313 struct _mesa_glsl_parse_state *state)
2315 ir_rvalue *result = NULL;
2317 YYLTYPE initializer_loc = decl->initializer->get_location();
2319 /* From page 24 (page 30 of the PDF) of the GLSL 1.10 spec:
2321 * "All uniform variables are read-only and are initialized either
2322 * directly by an application via API commands, or indirectly by
2325 if ((state->language_version <= 110)
2326 && (var->mode == ir_var_uniform)) {
2327 _mesa_glsl_error(& initializer_loc, state,
2328 "cannot initialize uniforms in GLSL 1.10");
2331 if (var->type->is_sampler()) {
2332 _mesa_glsl_error(& initializer_loc, state,
2333 "cannot initialize samplers");
2336 if ((var->mode == ir_var_in) && (state->current_function == NULL)) {
2337 _mesa_glsl_error(& initializer_loc, state,
2338 "cannot initialize %s shader input / %s",
2339 _mesa_glsl_shader_target_name(state->target),
2340 (state->target == vertex_shader)
2341 ? "attribute" : "varying");
2344 ir_dereference *const lhs = new(state) ir_dereference_variable(var);
2345 ir_rvalue *rhs = decl->initializer->hir(initializer_instructions,
2348 /* Calculate the constant value if this is a const or uniform
2351 if (type->qualifier.flags.q.constant
2352 || type->qualifier.flags.q.uniform) {
2353 ir_rvalue *new_rhs = validate_assignment(state, var->type, rhs, true);
2354 if (new_rhs != NULL) {
2357 ir_constant *constant_value = rhs->constant_expression_value();
2358 if (!constant_value) {
2359 _mesa_glsl_error(& initializer_loc, state,
2360 "initializer of %s variable `%s' must be a "
2361 "constant expression",
2362 (type->qualifier.flags.q.constant)
2363 ? "const" : "uniform",
2365 if (var->type->is_numeric()) {
2366 /* Reduce cascading errors. */
2367 var->constant_value = ir_constant::zero(state, var->type);
2370 rhs = constant_value;
2371 var->constant_value = constant_value;
2374 _mesa_glsl_error(&initializer_loc, state,
2375 "initializer of type %s cannot be assigned to "
2376 "variable of type %s",
2377 rhs->type->name, var->type->name);
2378 if (var->type->is_numeric()) {
2379 /* Reduce cascading errors. */
2380 var->constant_value = ir_constant::zero(state, var->type);
2385 if (rhs && !rhs->type->is_error()) {
2386 bool temp = var->read_only;
2387 if (type->qualifier.flags.q.constant)
2388 var->read_only = false;
2390 /* Never emit code to initialize a uniform.
2392 const glsl_type *initializer_type;
2393 if (!type->qualifier.flags.q.uniform) {
2394 result = do_assignment(initializer_instructions, state,
2397 type->get_location());
2398 initializer_type = result->type;
2400 initializer_type = rhs->type;
2402 var->constant_initializer = rhs->constant_expression_value();
2403 var->has_initializer = true;
2405 /* If the declared variable is an unsized array, it must inherrit
2406 * its full type from the initializer. A declaration such as
2408 * uniform float a[] = float[](1.0, 2.0, 3.0, 3.0);
2412 * uniform float a[4] = float[](1.0, 2.0, 3.0, 3.0);
2414 * The assignment generated in the if-statement (below) will also
2415 * automatically handle this case for non-uniforms.
2417 * If the declared variable is not an array, the types must
2418 * already match exactly. As a result, the type assignment
2419 * here can be done unconditionally. For non-uniforms the call
2420 * to do_assignment can change the type of the initializer (via
2421 * the implicit conversion rules). For uniforms the initializer
2422 * must be a constant expression, and the type of that expression
2423 * was validated above.
2425 var->type = initializer_type;
2427 var->read_only = temp;
2434 ast_declarator_list::hir(exec_list *instructions,
2435 struct _mesa_glsl_parse_state *state)
2438 const struct glsl_type *decl_type;
2439 const char *type_name = NULL;
2440 ir_rvalue *result = NULL;
2441 YYLTYPE loc = this->get_location();
2443 /* From page 46 (page 52 of the PDF) of the GLSL 1.50 spec:
2445 * "To ensure that a particular output variable is invariant, it is
2446 * necessary to use the invariant qualifier. It can either be used to
2447 * qualify a previously declared variable as being invariant
2449 * invariant gl_Position; // make existing gl_Position be invariant"
2451 * In these cases the parser will set the 'invariant' flag in the declarator
2452 * list, and the type will be NULL.
2454 if (this->invariant) {
2455 assert(this->type == NULL);
2457 if (state->current_function != NULL) {
2458 _mesa_glsl_error(& loc, state,
2459 "All uses of `invariant' keyword must be at global "
2463 foreach_list_typed (ast_declaration, decl, link, &this->declarations) {
2464 assert(!decl->is_array);
2465 assert(decl->array_size == NULL);
2466 assert(decl->initializer == NULL);
2468 ir_variable *const earlier =
2469 state->symbols->get_variable(decl->identifier);
2470 if (earlier == NULL) {
2471 _mesa_glsl_error(& loc, state,
2472 "Undeclared variable `%s' cannot be marked "
2473 "invariant\n", decl->identifier);
2474 } else if ((state->target == vertex_shader)
2475 && (earlier->mode != ir_var_out)) {
2476 _mesa_glsl_error(& loc, state,
2477 "`%s' cannot be marked invariant, vertex shader "
2478 "outputs only\n", decl->identifier);
2479 } else if ((state->target == fragment_shader)
2480 && (earlier->mode != ir_var_in)) {
2481 _mesa_glsl_error(& loc, state,
2482 "`%s' cannot be marked invariant, fragment shader "
2483 "inputs only\n", decl->identifier);
2484 } else if (earlier->used) {
2485 _mesa_glsl_error(& loc, state,
2486 "variable `%s' may not be redeclared "
2487 "`invariant' after being used",
2490 earlier->invariant = true;
2494 /* Invariant redeclarations do not have r-values.
2499 assert(this->type != NULL);
2500 assert(!this->invariant);
2502 /* The type specifier may contain a structure definition. Process that
2503 * before any of the variable declarations.
2505 (void) this->type->specifier->hir(instructions, state);
2507 decl_type = this->type->specifier->glsl_type(& type_name, state);
2508 if (this->declarations.is_empty()) {
2509 /* If there is no structure involved in the program text, there are two
2510 * possible scenarios:
2512 * - The program text contained something like 'vec4;'. This is an
2513 * empty declaration. It is valid but weird. Emit a warning.
2515 * - The program text contained something like 'S;' and 'S' is not the
2516 * name of a known structure type. This is both invalid and weird.
2519 * Note that if decl_type is NULL and there is a structure involved,
2520 * there must have been some sort of error with the structure. In this
2521 * case we assume that an error was already generated on this line of
2522 * code for the structure. There is no need to generate an additional,
2525 assert(this->type->specifier->structure == NULL || decl_type != NULL
2527 if (this->type->specifier->structure == NULL) {
2528 if (decl_type != NULL) {
2529 _mesa_glsl_warning(&loc, state, "empty declaration");
2531 _mesa_glsl_error(&loc, state,
2532 "invalid type `%s' in empty declaration",
2538 foreach_list_typed (ast_declaration, decl, link, &this->declarations) {
2539 const struct glsl_type *var_type;
2542 /* FINISHME: Emit a warning if a variable declaration shadows a
2543 * FINISHME: declaration at a higher scope.
2546 if ((decl_type == NULL) || decl_type->is_void()) {
2547 if (type_name != NULL) {
2548 _mesa_glsl_error(& loc, state,
2549 "invalid type `%s' in declaration of `%s'",
2550 type_name, decl->identifier);
2552 _mesa_glsl_error(& loc, state,
2553 "invalid type in declaration of `%s'",
2559 if (decl->is_array) {
2560 var_type = process_array_type(&loc, decl_type, decl->array_size,
2562 if (var_type->is_error())
2565 var_type = decl_type;
2568 var = new(ctx) ir_variable(var_type, decl->identifier, ir_var_auto);
2570 /* From page 22 (page 28 of the PDF) of the GLSL 1.10 specification;
2572 * "Global variables can only use the qualifiers const,
2573 * attribute, uni form, or varying. Only one may be
2576 * Local variables can only use the qualifier const."
2578 * This is relaxed in GLSL 1.30. It is also relaxed by any extension
2579 * that adds the 'layout' keyword.
2581 if ((state->language_version < 130)
2582 && !state->ARB_explicit_attrib_location_enable
2583 && !state->ARB_fragment_coord_conventions_enable) {
2584 if (this->type->qualifier.flags.q.out) {
2585 _mesa_glsl_error(& loc, state,
2586 "`out' qualifier in declaration of `%s' "
2587 "only valid for function parameters in %s.",
2588 decl->identifier, state->version_string);
2590 if (this->type->qualifier.flags.q.in) {
2591 _mesa_glsl_error(& loc, state,
2592 "`in' qualifier in declaration of `%s' "
2593 "only valid for function parameters in %s.",
2594 decl->identifier, state->version_string);
2596 /* FINISHME: Test for other invalid qualifiers. */
2599 apply_type_qualifier_to_variable(& this->type->qualifier, var, state,
2602 if (this->type->qualifier.flags.q.invariant) {
2603 if ((state->target == vertex_shader) && !(var->mode == ir_var_out ||
2604 var->mode == ir_var_inout)) {
2605 /* FINISHME: Note that this doesn't work for invariant on
2606 * a function signature outval
2608 _mesa_glsl_error(& loc, state,
2609 "`%s' cannot be marked invariant, vertex shader "
2610 "outputs only\n", var->name);
2611 } else if ((state->target == fragment_shader) &&
2612 !(var->mode == ir_var_in || var->mode == ir_var_inout)) {
2613 /* FINISHME: Note that this doesn't work for invariant on
2614 * a function signature inval
2616 _mesa_glsl_error(& loc, state,
2617 "`%s' cannot be marked invariant, fragment shader "
2618 "inputs only\n", var->name);
2622 if (state->current_function != NULL) {
2623 const char *mode = NULL;
2624 const char *extra = "";
2626 /* There is no need to check for 'inout' here because the parser will
2627 * only allow that in function parameter lists.
2629 if (this->type->qualifier.flags.q.attribute) {
2631 } else if (this->type->qualifier.flags.q.uniform) {
2633 } else if (this->type->qualifier.flags.q.varying) {
2635 } else if (this->type->qualifier.flags.q.in) {
2637 extra = " or in function parameter list";
2638 } else if (this->type->qualifier.flags.q.out) {
2640 extra = " or in function parameter list";
2644 _mesa_glsl_error(& loc, state,
2645 "%s variable `%s' must be declared at "
2647 mode, var->name, extra);
2649 } else if (var->mode == ir_var_in) {
2650 var->read_only = true;
2652 if (state->target == vertex_shader) {
2653 bool error_emitted = false;
2655 /* From page 31 (page 37 of the PDF) of the GLSL 1.50 spec:
2657 * "Vertex shader inputs can only be float, floating-point
2658 * vectors, matrices, signed and unsigned integers and integer
2659 * vectors. Vertex shader inputs can also form arrays of these
2660 * types, but not structures."
2662 * From page 31 (page 27 of the PDF) of the GLSL 1.30 spec:
2664 * "Vertex shader inputs can only be float, floating-point
2665 * vectors, matrices, signed and unsigned integers and integer
2666 * vectors. They cannot be arrays or structures."
2668 * From page 23 (page 29 of the PDF) of the GLSL 1.20 spec:
2670 * "The attribute qualifier can be used only with float,
2671 * floating-point vectors, and matrices. Attribute variables
2672 * cannot be declared as arrays or structures."
2674 const glsl_type *check_type = var->type->is_array()
2675 ? var->type->fields.array : var->type;
2677 switch (check_type->base_type) {
2678 case GLSL_TYPE_FLOAT:
2680 case GLSL_TYPE_UINT:
2682 if (state->language_version > 120)
2686 _mesa_glsl_error(& loc, state,
2687 "vertex shader input / attribute cannot have "
2689 var->type->is_array() ? "array of " : "",
2691 error_emitted = true;
2694 if (!error_emitted && (state->language_version <= 130)
2695 && var->type->is_array()) {
2696 _mesa_glsl_error(& loc, state,
2697 "vertex shader input / attribute cannot have "
2699 error_emitted = true;
2704 /* Integer vertex outputs must be qualified with 'flat'.
2706 * From section 4.3.6 of the GLSL 1.30 spec:
2707 * "If a vertex output is a signed or unsigned integer or integer
2708 * vector, then it must be qualified with the interpolation qualifier
2711 if (state->language_version >= 130
2712 && state->target == vertex_shader
2713 && state->current_function == NULL
2714 && var->type->is_integer()
2715 && var->mode == ir_var_out
2716 && var->interpolation != INTERP_QUALIFIER_FLAT) {
2718 _mesa_glsl_error(&loc, state, "If a vertex output is an integer, "
2719 "then it must be qualified with 'flat'");
2723 /* Interpolation qualifiers cannot be applied to 'centroid' and
2724 * 'centroid varying'.
2726 * From page 29 (page 35 of the PDF) of the GLSL 1.30 spec:
2727 * "interpolation qualifiers may only precede the qualifiers in,
2728 * centroid in, out, or centroid out in a declaration. They do not apply
2729 * to the deprecated storage qualifiers varying or centroid varying."
2731 if (state->language_version >= 130
2732 && this->type->qualifier.has_interpolation()
2733 && this->type->qualifier.flags.q.varying) {
2735 const char *i = this->type->qualifier.interpolation_string();
2738 if (this->type->qualifier.flags.q.centroid)
2739 s = "centroid varying";
2743 _mesa_glsl_error(&loc, state,
2744 "qualifier '%s' cannot be applied to the "
2745 "deprecated storage qualifier '%s'", i, s);
2749 /* Interpolation qualifiers can only apply to vertex shader outputs and
2750 * fragment shader inputs.
2752 * From page 29 (page 35 of the PDF) of the GLSL 1.30 spec:
2753 * "Outputs from a vertex shader (out) and inputs to a fragment
2754 * shader (in) can be further qualified with one or more of these
2755 * interpolation qualifiers"
2757 if (state->language_version >= 130
2758 && this->type->qualifier.has_interpolation()) {
2760 const char *i = this->type->qualifier.interpolation_string();
2763 switch (state->target) {
2765 if (this->type->qualifier.flags.q.in) {
2766 _mesa_glsl_error(&loc, state,
2767 "qualifier '%s' cannot be applied to vertex "
2768 "shader inputs", i);
2771 case fragment_shader:
2772 if (this->type->qualifier.flags.q.out) {
2773 _mesa_glsl_error(&loc, state,
2774 "qualifier '%s' cannot be applied to fragment "
2775 "shader outputs", i);
2784 /* From section 4.3.4 of the GLSL 1.30 spec:
2785 * "It is an error to use centroid in in a vertex shader."
2787 if (state->language_version >= 130
2788 && this->type->qualifier.flags.q.centroid
2789 && this->type->qualifier.flags.q.in
2790 && state->target == vertex_shader) {
2792 _mesa_glsl_error(&loc, state,
2793 "'centroid in' cannot be used in a vertex shader");
2797 /* Precision qualifiers exists only in GLSL versions 1.00 and >= 1.30.
2799 if (this->type->specifier->precision != ast_precision_none
2800 && state->language_version != 100
2801 && state->language_version < 130) {
2803 _mesa_glsl_error(&loc, state,
2804 "precision qualifiers are supported only in GLSL ES "
2805 "1.00, and GLSL 1.30 and later");
2809 /* Precision qualifiers only apply to floating point and integer types.
2811 * From section 4.5.2 of the GLSL 1.30 spec:
2812 * "Any floating point or any integer declaration can have the type
2813 * preceded by one of these precision qualifiers [...] Literal
2814 * constants do not have precision qualifiers. Neither do Boolean
2817 * In GLSL ES, sampler types are also allowed.
2819 * From page 87 of the GLSL ES spec:
2820 * "RESOLUTION: Allow sampler types to take a precision qualifier."
2822 if (this->type->specifier->precision != ast_precision_none
2823 && !var->type->is_float()
2824 && !var->type->is_integer()
2825 && !(var->type->is_sampler() && state->es_shader)
2826 && !(var->type->is_array()
2827 && (var->type->fields.array->is_float()
2828 || var->type->fields.array->is_integer()))) {
2830 _mesa_glsl_error(&loc, state,
2831 "precision qualifiers apply only to floating point"
2832 "%s types", state->es_shader ? ", integer, and sampler"
2836 /* From page 17 (page 23 of the PDF) of the GLSL 1.20 spec:
2838 * "[Sampler types] can only be declared as function
2839 * parameters or uniform variables (see Section 4.3.5
2842 if (var_type->contains_sampler() &&
2843 !this->type->qualifier.flags.q.uniform) {
2844 _mesa_glsl_error(&loc, state, "samplers must be declared uniform");
2847 /* Process the initializer and add its instructions to a temporary
2848 * list. This list will be added to the instruction stream (below) after
2849 * the declaration is added. This is done because in some cases (such as
2850 * redeclarations) the declaration may not actually be added to the
2851 * instruction stream.
2853 exec_list initializer_instructions;
2854 ir_variable *earlier = get_variable_being_redeclared(var, decl, state);
2856 if (decl->initializer != NULL) {
2857 result = process_initializer((earlier == NULL) ? var : earlier,
2859 &initializer_instructions, state);
2862 /* From page 23 (page 29 of the PDF) of the GLSL 1.10 spec:
2864 * "It is an error to write to a const variable outside of
2865 * its declaration, so they must be initialized when
2868 if (this->type->qualifier.flags.q.constant && decl->initializer == NULL) {
2869 _mesa_glsl_error(& loc, state,
2870 "const declaration of `%s' must be initialized",
2874 /* If the declaration is not a redeclaration, there are a few additional
2875 * semantic checks that must be applied. In addition, variable that was
2876 * created for the declaration should be added to the IR stream.
2878 if (earlier == NULL) {
2879 /* From page 15 (page 21 of the PDF) of the GLSL 1.10 spec,
2881 * "Identifiers starting with "gl_" are reserved for use by
2882 * OpenGL, and may not be declared in a shader as either a
2883 * variable or a function."
2885 if (strncmp(decl->identifier, "gl_", 3) == 0)
2886 _mesa_glsl_error(& loc, state,
2887 "identifier `%s' uses reserved `gl_' prefix",
2889 else if (strstr(decl->identifier, "__")) {
2890 /* From page 14 (page 20 of the PDF) of the GLSL 1.10
2893 * "In addition, all identifiers containing two
2894 * consecutive underscores (__) are reserved as
2895 * possible future keywords."
2897 _mesa_glsl_error(& loc, state,
2898 "identifier `%s' uses reserved `__' string",
2902 /* Add the variable to the symbol table. Note that the initializer's
2903 * IR was already processed earlier (though it hasn't been emitted
2904 * yet), without the variable in scope.
2906 * This differs from most C-like languages, but it follows the GLSL
2907 * specification. From page 28 (page 34 of the PDF) of the GLSL 1.50
2910 * "Within a declaration, the scope of a name starts immediately
2911 * after the initializer if present or immediately after the name
2912 * being declared if not."
2914 if (!state->symbols->add_variable(var)) {
2915 YYLTYPE loc = this->get_location();
2916 _mesa_glsl_error(&loc, state, "name `%s' already taken in the "
2917 "current scope", decl->identifier);
2921 /* Push the variable declaration to the top. It means that all the
2922 * variable declarations will appear in a funny last-to-first order,
2923 * but otherwise we run into trouble if a function is prototyped, a
2924 * global var is decled, then the function is defined with usage of
2925 * the global var. See glslparsertest's CorrectModule.frag.
2927 instructions->push_head(var);
2930 instructions->append_list(&initializer_instructions);
2934 /* Generally, variable declarations do not have r-values. However,
2935 * one is used for the declaration in
2937 * while (bool b = some_condition()) {
2941 * so we return the rvalue from the last seen declaration here.
2948 ast_parameter_declarator::hir(exec_list *instructions,
2949 struct _mesa_glsl_parse_state *state)
2952 const struct glsl_type *type;
2953 const char *name = NULL;
2954 YYLTYPE loc = this->get_location();
2956 type = this->type->specifier->glsl_type(& name, state);
2960 _mesa_glsl_error(& loc, state,
2961 "invalid type `%s' in declaration of `%s'",
2962 name, this->identifier);
2964 _mesa_glsl_error(& loc, state,
2965 "invalid type in declaration of `%s'",
2969 type = glsl_type::error_type;
2972 /* From page 62 (page 68 of the PDF) of the GLSL 1.50 spec:
2974 * "Functions that accept no input arguments need not use void in the
2975 * argument list because prototypes (or definitions) are required and
2976 * therefore there is no ambiguity when an empty argument list "( )" is
2977 * declared. The idiom "(void)" as a parameter list is provided for
2980 * Placing this check here prevents a void parameter being set up
2981 * for a function, which avoids tripping up checks for main taking
2982 * parameters and lookups of an unnamed symbol.
2984 if (type->is_void()) {
2985 if (this->identifier != NULL)
2986 _mesa_glsl_error(& loc, state,
2987 "named parameter cannot have type `void'");
2993 if (formal_parameter && (this->identifier == NULL)) {
2994 _mesa_glsl_error(& loc, state, "formal parameter lacks a name");
2998 /* This only handles "vec4 foo[..]". The earlier specifier->glsl_type(...)
2999 * call already handled the "vec4[..] foo" case.
3001 if (this->is_array) {
3002 type = process_array_type(&loc, type, this->array_size, state);
3005 if (!type->is_error() && type->array_size() == 0) {
3006 _mesa_glsl_error(&loc, state, "arrays passed as parameters must have "
3007 "a declared size.");
3008 type = glsl_type::error_type;
3012 ir_variable *var = new(ctx) ir_variable(type, this->identifier, ir_var_in);
3014 /* Apply any specified qualifiers to the parameter declaration. Note that
3015 * for function parameters the default mode is 'in'.
3017 apply_type_qualifier_to_variable(& this->type->qualifier, var, state, & loc);
3019 /* From page 17 (page 23 of the PDF) of the GLSL 1.20 spec:
3021 * "Samplers cannot be treated as l-values; hence cannot be used
3022 * as out or inout function parameters, nor can they be assigned
3025 if ((var->mode == ir_var_inout || var->mode == ir_var_out)
3026 && type->contains_sampler()) {
3027 _mesa_glsl_error(&loc, state, "out and inout parameters cannot contain samplers");
3028 type = glsl_type::error_type;
3031 /* From page 39 (page 45 of the PDF) of the GLSL 1.10 spec:
3033 * "When calling a function, expressions that do not evaluate to
3034 * l-values cannot be passed to parameters declared as out or inout."
3036 * From page 32 (page 38 of the PDF) of the GLSL 1.10 spec:
3038 * "Other binary or unary expressions, non-dereferenced arrays,
3039 * function names, swizzles with repeated fields, and constants
3040 * cannot be l-values."
3042 * So for GLSL 1.10, passing an array as an out or inout parameter is not
3043 * allowed. This restriction is removed in GLSL 1.20, and in GLSL ES.
3045 if ((var->mode == ir_var_inout || var->mode == ir_var_out)
3046 && type->is_array() && state->language_version == 110) {
3047 _mesa_glsl_error(&loc, state, "Arrays cannot be out or inout parameters in GLSL 1.10");
3048 type = glsl_type::error_type;
3051 instructions->push_tail(var);
3053 /* Parameter declarations do not have r-values.
3060 ast_parameter_declarator::parameters_to_hir(exec_list *ast_parameters,
3062 exec_list *ir_parameters,
3063 _mesa_glsl_parse_state *state)
3065 ast_parameter_declarator *void_param = NULL;
3068 foreach_list_typed (ast_parameter_declarator, param, link, ast_parameters) {
3069 param->formal_parameter = formal;
3070 param->hir(ir_parameters, state);
3078 if ((void_param != NULL) && (count > 1)) {
3079 YYLTYPE loc = void_param->get_location();
3081 _mesa_glsl_error(& loc, state,
3082 "`void' parameter must be only parameter");
3088 emit_function(_mesa_glsl_parse_state *state, ir_function *f)
3090 /* IR invariants disallow function declarations or definitions
3091 * nested within other function definitions. But there is no
3092 * requirement about the relative order of function declarations
3093 * and definitions with respect to one another. So simply insert
3094 * the new ir_function block at the end of the toplevel instruction
3097 state->toplevel_ir->push_tail(f);
3102 ast_function::hir(exec_list *instructions,
3103 struct _mesa_glsl_parse_state *state)
3106 ir_function *f = NULL;
3107 ir_function_signature *sig = NULL;
3108 exec_list hir_parameters;
3110 const char *const name = identifier;
3112 /* New functions are always added to the top-level IR instruction stream,
3113 * so this instruction list pointer is ignored. See also emit_function
3116 (void) instructions;
3118 /* From page 21 (page 27 of the PDF) of the GLSL 1.20 spec,
3120 * "Function declarations (prototypes) cannot occur inside of functions;
3121 * they must be at global scope, or for the built-in functions, outside
3122 * the global scope."
3124 * From page 27 (page 33 of the PDF) of the GLSL ES 1.00.16 spec,
3126 * "User defined functions may only be defined within the global scope."
3128 * Note that this language does not appear in GLSL 1.10.
3130 if ((state->current_function != NULL) && (state->language_version != 110)) {
3131 YYLTYPE loc = this->get_location();
3132 _mesa_glsl_error(&loc, state,
3133 "declaration of function `%s' not allowed within "
3134 "function body", name);
3137 /* From page 15 (page 21 of the PDF) of the GLSL 1.10 spec,
3139 * "Identifiers starting with "gl_" are reserved for use by
3140 * OpenGL, and may not be declared in a shader as either a
3141 * variable or a function."
3143 if (strncmp(name, "gl_", 3) == 0) {
3144 YYLTYPE loc = this->get_location();
3145 _mesa_glsl_error(&loc, state,
3146 "identifier `%s' uses reserved `gl_' prefix", name);
3149 /* Convert the list of function parameters to HIR now so that they can be
3150 * used below to compare this function's signature with previously seen
3151 * signatures for functions with the same name.
3153 ast_parameter_declarator::parameters_to_hir(& this->parameters,
3155 & hir_parameters, state);
3157 const char *return_type_name;
3158 const glsl_type *return_type =
3159 this->return_type->specifier->glsl_type(& return_type_name, state);
3162 YYLTYPE loc = this->get_location();
3163 _mesa_glsl_error(&loc, state,
3164 "function `%s' has undeclared return type `%s'",
3165 name, return_type_name);
3166 return_type = glsl_type::error_type;
3169 /* From page 56 (page 62 of the PDF) of the GLSL 1.30 spec:
3170 * "No qualifier is allowed on the return type of a function."
3172 if (this->return_type->has_qualifiers()) {
3173 YYLTYPE loc = this->get_location();
3174 _mesa_glsl_error(& loc, state,
3175 "function `%s' return type has qualifiers", name);
3178 /* From page 17 (page 23 of the PDF) of the GLSL 1.20 spec:
3180 * "[Sampler types] can only be declared as function parameters
3181 * or uniform variables (see Section 4.3.5 "Uniform")".
3183 if (return_type->contains_sampler()) {
3184 YYLTYPE loc = this->get_location();
3185 _mesa_glsl_error(&loc, state,
3186 "function `%s' return type can't contain a sampler",
3190 /* Verify that this function's signature either doesn't match a previously
3191 * seen signature for a function with the same name, or, if a match is found,
3192 * that the previously seen signature does not have an associated definition.
3194 f = state->symbols->get_function(name);
3195 if (f != NULL && (state->es_shader || f->has_user_signature())) {
3196 sig = f->exact_matching_signature(&hir_parameters);
3198 const char *badvar = sig->qualifiers_match(&hir_parameters);
3199 if (badvar != NULL) {
3200 YYLTYPE loc = this->get_location();
3202 _mesa_glsl_error(&loc, state, "function `%s' parameter `%s' "
3203 "qualifiers don't match prototype", name, badvar);
3206 if (sig->return_type != return_type) {
3207 YYLTYPE loc = this->get_location();
3209 _mesa_glsl_error(&loc, state, "function `%s' return type doesn't "
3210 "match prototype", name);
3213 if (is_definition && sig->is_defined) {
3214 YYLTYPE loc = this->get_location();
3216 _mesa_glsl_error(& loc, state, "function `%s' redefined", name);
3220 f = new(ctx) ir_function(name);
3221 if (!state->symbols->add_function(f)) {
3222 /* This function name shadows a non-function use of the same name. */
3223 YYLTYPE loc = this->get_location();
3225 _mesa_glsl_error(&loc, state, "function name `%s' conflicts with "
3226 "non-function", name);
3230 emit_function(state, f);
3233 /* Verify the return type of main() */
3234 if (strcmp(name, "main") == 0) {
3235 if (! return_type->is_void()) {
3236 YYLTYPE loc = this->get_location();
3238 _mesa_glsl_error(& loc, state, "main() must return void");
3241 if (!hir_parameters.is_empty()) {
3242 YYLTYPE loc = this->get_location();
3244 _mesa_glsl_error(& loc, state, "main() must not take any parameters");
3248 /* Finish storing the information about this new function in its signature.
3251 sig = new(ctx) ir_function_signature(return_type);
3252 f->add_signature(sig);
3255 sig->replace_parameters(&hir_parameters);
3258 /* Function declarations (prototypes) do not have r-values.
3265 ast_function_definition::hir(exec_list *instructions,
3266 struct _mesa_glsl_parse_state *state)
3268 prototype->is_definition = true;
3269 prototype->hir(instructions, state);
3271 ir_function_signature *signature = prototype->signature;
3272 if (signature == NULL)
3275 assert(state->current_function == NULL);
3276 state->current_function = signature;
3277 state->found_return = false;
3279 /* Duplicate parameters declared in the prototype as concrete variables.
3280 * Add these to the symbol table.
3282 state->symbols->push_scope();
3283 foreach_iter(exec_list_iterator, iter, signature->parameters) {
3284 ir_variable *const var = ((ir_instruction *) iter.get())->as_variable();
3286 assert(var != NULL);
3288 /* The only way a parameter would "exist" is if two parameters have
3291 if (state->symbols->name_declared_this_scope(var->name)) {
3292 YYLTYPE loc = this->get_location();
3294 _mesa_glsl_error(& loc, state, "parameter `%s' redeclared", var->name);
3296 state->symbols->add_variable(var);
3300 /* Convert the body of the function to HIR. */
3301 this->body->hir(&signature->body, state);
3302 signature->is_defined = true;
3304 state->symbols->pop_scope();
3306 assert(state->current_function == signature);
3307 state->current_function = NULL;
3309 if (!signature->return_type->is_void() && !state->found_return) {
3310 YYLTYPE loc = this->get_location();
3311 _mesa_glsl_error(& loc, state, "function `%s' has non-void return type "
3312 "%s, but no return statement",
3313 signature->function_name(),
3314 signature->return_type->name);
3317 /* Function definitions do not have r-values.
3324 ast_jump_statement::hir(exec_list *instructions,
3325 struct _mesa_glsl_parse_state *state)
3332 assert(state->current_function);
3334 if (opt_return_value) {
3335 ir_rvalue *const ret = opt_return_value->hir(instructions, state);
3337 /* The value of the return type can be NULL if the shader says
3338 * 'return foo();' and foo() is a function that returns void.
3340 * NOTE: The GLSL spec doesn't say that this is an error. The type
3341 * of the return value is void. If the return type of the function is
3342 * also void, then this should compile without error. Seriously.
3344 const glsl_type *const ret_type =
3345 (ret == NULL) ? glsl_type::void_type : ret->type;
3347 /* Implicit conversions are not allowed for return values. */
3348 if (state->current_function->return_type != ret_type) {
3349 YYLTYPE loc = this->get_location();
3351 _mesa_glsl_error(& loc, state,
3352 "`return' with wrong type %s, in function `%s' "
3355 state->current_function->function_name(),
3356 state->current_function->return_type->name);
3359 inst = new(ctx) ir_return(ret);
3361 if (state->current_function->return_type->base_type !=
3363 YYLTYPE loc = this->get_location();
3365 _mesa_glsl_error(& loc, state,
3366 "`return' with no value, in function %s returning "
3368 state->current_function->function_name());
3370 inst = new(ctx) ir_return;
3373 state->found_return = true;
3374 instructions->push_tail(inst);
3379 if (state->target != fragment_shader) {
3380 YYLTYPE loc = this->get_location();
3382 _mesa_glsl_error(& loc, state,
3383 "`discard' may only appear in a fragment shader");
3385 instructions->push_tail(new(ctx) ir_discard);
3390 if (mode == ast_continue &&
3391 state->loop_nesting_ast == NULL) {
3392 YYLTYPE loc = this->get_location();
3394 _mesa_glsl_error(& loc, state,
3395 "continue may only appear in a loop");
3396 } else if (mode == ast_break &&
3397 state->loop_nesting_ast == NULL &&
3398 state->switch_state.switch_nesting_ast == NULL) {
3399 YYLTYPE loc = this->get_location();
3401 _mesa_glsl_error(& loc, state,
3402 "break may only appear in a loop or a switch");
3404 /* For a loop, inline the for loop expression again,
3405 * since we don't know where near the end of
3406 * the loop body the normal copy of it
3407 * is going to be placed.
3409 if (state->loop_nesting_ast != NULL &&
3410 mode == ast_continue &&
3411 state->loop_nesting_ast->rest_expression) {
3412 state->loop_nesting_ast->rest_expression->hir(instructions,
3416 if (state->switch_state.is_switch_innermost &&
3417 mode == ast_break) {
3418 /* Force break out of switch by setting is_break switch state.
3420 ir_variable *const is_break_var = state->switch_state.is_break_var;
3421 ir_dereference_variable *const deref_is_break_var =
3422 new(ctx) ir_dereference_variable(is_break_var);
3423 ir_constant *const true_val = new(ctx) ir_constant(true);
3424 ir_assignment *const set_break_var =
3425 new(ctx) ir_assignment(deref_is_break_var,
3429 instructions->push_tail(set_break_var);
3432 ir_loop_jump *const jump =
3433 new(ctx) ir_loop_jump((mode == ast_break)
3434 ? ir_loop_jump::jump_break
3435 : ir_loop_jump::jump_continue);
3436 instructions->push_tail(jump);
3443 /* Jump instructions do not have r-values.
3450 ast_selection_statement::hir(exec_list *instructions,
3451 struct _mesa_glsl_parse_state *state)
3455 ir_rvalue *const condition = this->condition->hir(instructions, state);
3457 /* From page 66 (page 72 of the PDF) of the GLSL 1.50 spec:
3459 * "Any expression whose type evaluates to a Boolean can be used as the
3460 * conditional expression bool-expression. Vector types are not accepted
3461 * as the expression to if."
3463 * The checks are separated so that higher quality diagnostics can be
3464 * generated for cases where both rules are violated.
3466 if (!condition->type->is_boolean() || !condition->type->is_scalar()) {
3467 YYLTYPE loc = this->condition->get_location();
3469 _mesa_glsl_error(& loc, state, "if-statement condition must be scalar "
3473 ir_if *const stmt = new(ctx) ir_if(condition);
3475 if (then_statement != NULL) {
3476 state->symbols->push_scope();
3477 then_statement->hir(& stmt->then_instructions, state);
3478 state->symbols->pop_scope();
3481 if (else_statement != NULL) {
3482 state->symbols->push_scope();
3483 else_statement->hir(& stmt->else_instructions, state);
3484 state->symbols->pop_scope();
3487 instructions->push_tail(stmt);
3489 /* if-statements do not have r-values.
3496 ast_switch_statement::hir(exec_list *instructions,
3497 struct _mesa_glsl_parse_state *state)
3501 ir_rvalue *const test_expression =
3502 this->test_expression->hir(instructions, state);
3504 /* From page 66 (page 55 of the PDF) of the GLSL 1.50 spec:
3506 * "The type of init-expression in a switch statement must be a
3509 * The checks are separated so that higher quality diagnostics can be
3510 * generated for cases where the rule is violated.
3512 if (!test_expression->type->is_integer()) {
3513 YYLTYPE loc = this->test_expression->get_location();
3515 _mesa_glsl_error(& loc,
3517 "switch-statement expression must be scalar "
3521 /* Track the switch-statement nesting in a stack-like manner.
3523 struct glsl_switch_state saved = state->switch_state;
3525 state->switch_state.is_switch_innermost = true;
3526 state->switch_state.switch_nesting_ast = this;
3527 state->switch_state.labels_ht = hash_table_ctor(0, hash_table_pointer_hash,
3528 hash_table_pointer_compare);
3529 state->switch_state.previous_default = NULL;
3531 /* Initalize is_fallthru state to false.
3533 ir_rvalue *const is_fallthru_val = new (ctx) ir_constant(false);
3534 state->switch_state.is_fallthru_var =
3535 new(ctx) ir_variable(glsl_type::bool_type,
3536 "switch_is_fallthru_tmp",
3538 instructions->push_tail(state->switch_state.is_fallthru_var);
3540 ir_dereference_variable *deref_is_fallthru_var =
3541 new(ctx) ir_dereference_variable(state->switch_state.is_fallthru_var);
3542 instructions->push_tail(new(ctx) ir_assignment(deref_is_fallthru_var,
3546 /* Initalize is_break state to false.
3548 ir_rvalue *const is_break_val = new (ctx) ir_constant(false);
3549 state->switch_state.is_break_var = new(ctx) ir_variable(glsl_type::bool_type,
3550 "switch_is_break_tmp",
3552 instructions->push_tail(state->switch_state.is_break_var);
3554 ir_dereference_variable *deref_is_break_var =
3555 new(ctx) ir_dereference_variable(state->switch_state.is_break_var);
3556 instructions->push_tail(new(ctx) ir_assignment(deref_is_break_var,
3560 /* Cache test expression.
3562 test_to_hir(instructions, state);
3564 /* Emit code for body of switch stmt.
3566 body->hir(instructions, state);
3568 hash_table_dtor(state->switch_state.labels_ht);
3570 state->switch_state = saved;
3572 /* Switch statements do not have r-values.
3579 ast_switch_statement::test_to_hir(exec_list *instructions,
3580 struct _mesa_glsl_parse_state *state)
3584 /* Cache value of test expression.
3586 ir_rvalue *const test_val =
3587 test_expression->hir(instructions,
3590 state->switch_state.test_var = new(ctx) ir_variable(glsl_type::int_type,
3593 ir_dereference_variable *deref_test_var =
3594 new(ctx) ir_dereference_variable(state->switch_state.test_var);
3596 instructions->push_tail(state->switch_state.test_var);
3597 instructions->push_tail(new(ctx) ir_assignment(deref_test_var,
3604 ast_switch_body::hir(exec_list *instructions,
3605 struct _mesa_glsl_parse_state *state)
3608 stmts->hir(instructions, state);
3610 /* Switch bodies do not have r-values.
3617 ast_case_statement_list::hir(exec_list *instructions,
3618 struct _mesa_glsl_parse_state *state)
3620 foreach_list_typed (ast_case_statement, case_stmt, link, & this->cases)
3621 case_stmt->hir(instructions, state);
3623 /* Case statements do not have r-values.
3630 ast_case_statement::hir(exec_list *instructions,
3631 struct _mesa_glsl_parse_state *state)
3633 labels->hir(instructions, state);
3635 /* Conditionally set fallthru state based on break state.
3637 ir_constant *const false_val = new(state) ir_constant(false);
3638 ir_dereference_variable *const deref_is_fallthru_var =
3639 new(state) ir_dereference_variable(state->switch_state.is_fallthru_var);
3640 ir_dereference_variable *const deref_is_break_var =
3641 new(state) ir_dereference_variable(state->switch_state.is_break_var);
3642 ir_assignment *const reset_fallthru_on_break =
3643 new(state) ir_assignment(deref_is_fallthru_var,
3645 deref_is_break_var);
3646 instructions->push_tail(reset_fallthru_on_break);
3648 /* Guard case statements depending on fallthru state.
3650 ir_dereference_variable *const deref_fallthru_guard =
3651 new(state) ir_dereference_variable(state->switch_state.is_fallthru_var);
3652 ir_if *const test_fallthru = new(state) ir_if(deref_fallthru_guard);
3654 foreach_list_typed (ast_node, stmt, link, & this->stmts)
3655 stmt->hir(& test_fallthru->then_instructions, state);
3657 instructions->push_tail(test_fallthru);
3659 /* Case statements do not have r-values.
3666 ast_case_label_list::hir(exec_list *instructions,
3667 struct _mesa_glsl_parse_state *state)
3669 foreach_list_typed (ast_case_label, label, link, & this->labels)
3670 label->hir(instructions, state);
3672 /* Case labels do not have r-values.
3679 ast_case_label::hir(exec_list *instructions,
3680 struct _mesa_glsl_parse_state *state)
3684 ir_dereference_variable *deref_fallthru_var =
3685 new(ctx) ir_dereference_variable(state->switch_state.is_fallthru_var);
3687 ir_rvalue *const true_val = new(ctx) ir_constant(true);
3689 /* If not default case, ...
3691 if (this->test_value != NULL) {
3692 /* Conditionally set fallthru state based on
3693 * comparison of cached test expression value to case label.
3695 ir_rvalue *const label_rval = this->test_value->hir(instructions, state);
3696 ir_constant *label_const = label_rval->constant_expression_value();
3699 YYLTYPE loc = this->test_value->get_location();
3701 _mesa_glsl_error(& loc, state,
3702 "switch statement case label must be a "
3703 "constant expression");
3705 /* Stuff a dummy value in to allow processing to continue. */
3706 label_const = new(ctx) ir_constant(0);
3708 ast_expression *previous_label = (ast_expression *)
3709 hash_table_find(state->switch_state.labels_ht,
3710 (void *)(uintptr_t)label_const->value.u[0]);
3712 if (previous_label) {
3713 YYLTYPE loc = this->test_value->get_location();
3714 _mesa_glsl_error(& loc, state,
3715 "duplicate case value");
3717 loc = previous_label->get_location();
3718 _mesa_glsl_error(& loc, state,
3719 "this is the previous case label");
3721 hash_table_insert(state->switch_state.labels_ht,
3723 (void *)(uintptr_t)label_const->value.u[0]);
3727 ir_dereference_variable *deref_test_var =
3728 new(ctx) ir_dereference_variable(state->switch_state.test_var);
3730 ir_rvalue *const test_cond = new(ctx) ir_expression(ir_binop_all_equal,
3731 glsl_type::bool_type,
3735 ir_assignment *set_fallthru_on_test =
3736 new(ctx) ir_assignment(deref_fallthru_var,
3740 instructions->push_tail(set_fallthru_on_test);
3741 } else { /* default case */
3742 if (state->switch_state.previous_default) {
3744 YYLTYPE loc = this->get_location();
3745 _mesa_glsl_error(& loc, state,
3746 "multiple default labels in one switch");
3750 loc = state->switch_state.previous_default->get_location();
3751 _mesa_glsl_error(& loc, state,
3752 "this is the first default label");
3754 state->switch_state.previous_default = this;
3756 /* Set falltrhu state.
3758 ir_assignment *set_fallthru =
3759 new(ctx) ir_assignment(deref_fallthru_var,
3763 instructions->push_tail(set_fallthru);
3766 /* Case statements do not have r-values.
3773 ast_iteration_statement::condition_to_hir(ir_loop *stmt,
3774 struct _mesa_glsl_parse_state *state)
3778 if (condition != NULL) {
3779 ir_rvalue *const cond =
3780 condition->hir(& stmt->body_instructions, state);
3783 || !cond->type->is_boolean() || !cond->type->is_scalar()) {
3784 YYLTYPE loc = condition->get_location();
3786 _mesa_glsl_error(& loc, state,
3787 "loop condition must be scalar boolean");
3789 /* As the first code in the loop body, generate a block that looks
3790 * like 'if (!condition) break;' as the loop termination condition.
3792 ir_rvalue *const not_cond =
3793 new(ctx) ir_expression(ir_unop_logic_not, glsl_type::bool_type, cond,
3796 ir_if *const if_stmt = new(ctx) ir_if(not_cond);
3798 ir_jump *const break_stmt =
3799 new(ctx) ir_loop_jump(ir_loop_jump::jump_break);
3801 if_stmt->then_instructions.push_tail(break_stmt);
3802 stmt->body_instructions.push_tail(if_stmt);
3809 ast_iteration_statement::hir(exec_list *instructions,
3810 struct _mesa_glsl_parse_state *state)
3814 /* For-loops and while-loops start a new scope, but do-while loops do not.
3816 if (mode != ast_do_while)
3817 state->symbols->push_scope();
3819 if (init_statement != NULL)
3820 init_statement->hir(instructions, state);
3822 ir_loop *const stmt = new(ctx) ir_loop();
3823 instructions->push_tail(stmt);
3825 /* Track the current loop nesting.
3827 ast_iteration_statement *nesting_ast = state->loop_nesting_ast;
3829 state->loop_nesting_ast = this;
3831 /* Likewise, indicate that following code is closest to a loop,
3832 * NOT closest to a switch.
3834 bool saved_is_switch_innermost = state->switch_state.is_switch_innermost;
3835 state->switch_state.is_switch_innermost = false;
3837 if (mode != ast_do_while)
3838 condition_to_hir(stmt, state);
3841 body->hir(& stmt->body_instructions, state);
3843 if (rest_expression != NULL)
3844 rest_expression->hir(& stmt->body_instructions, state);
3846 if (mode == ast_do_while)
3847 condition_to_hir(stmt, state);
3849 if (mode != ast_do_while)
3850 state->symbols->pop_scope();
3852 /* Restore previous nesting before returning.
3854 state->loop_nesting_ast = nesting_ast;
3855 state->switch_state.is_switch_innermost = saved_is_switch_innermost;
3857 /* Loops do not have r-values.
3864 ast_type_specifier::hir(exec_list *instructions,
3865 struct _mesa_glsl_parse_state *state)
3867 if (!this->is_precision_statement && this->structure == NULL)
3870 YYLTYPE loc = this->get_location();
3872 if (this->precision != ast_precision_none
3873 && state->language_version != 100
3874 && state->language_version < 130) {
3875 _mesa_glsl_error(&loc, state,
3876 "precision qualifiers exist only in "
3877 "GLSL ES 1.00, and GLSL 1.30 and later");
3880 if (this->precision != ast_precision_none
3881 && this->structure != NULL) {
3882 _mesa_glsl_error(&loc, state,
3883 "precision qualifiers do not apply to structures");
3887 /* If this is a precision statement, check that the type to which it is
3888 * applied is either float or int.
3890 * From section 4.5.3 of the GLSL 1.30 spec:
3891 * "The precision statement
3892 * precision precision-qualifier type;
3893 * can be used to establish a default precision qualifier. The type
3894 * field can be either int or float [...]. Any other types or
3895 * qualifiers will result in an error.
3897 if (this->is_precision_statement) {
3898 assert(this->precision != ast_precision_none);
3899 assert(this->structure == NULL); /* The check for structures was
3900 * performed above. */
3901 if (this->is_array) {
3902 _mesa_glsl_error(&loc, state,
3903 "default precision statements do not apply to "
3907 if (this->type_specifier != ast_float
3908 && this->type_specifier != ast_int) {
3909 _mesa_glsl_error(&loc, state,
3910 "default precision statements apply only to types "
3915 /* FINISHME: Translate precision statements into IR. */
3919 if (this->structure != NULL)
3920 return this->structure->hir(instructions, state);
3927 ast_struct_specifier::hir(exec_list *instructions,
3928 struct _mesa_glsl_parse_state *state)
3930 unsigned decl_count = 0;
3932 /* Make an initial pass over the list of structure fields to determine how
3933 * many there are. Each element in this list is an ast_declarator_list.
3934 * This means that we actually need to count the number of elements in the
3935 * 'declarations' list in each of the elements.
3937 foreach_list_typed (ast_declarator_list, decl_list, link,
3938 &this->declarations) {
3939 foreach_list_const (decl_ptr, & decl_list->declarations) {
3944 /* Allocate storage for the structure fields and process the field
3945 * declarations. As the declarations are processed, try to also convert
3946 * the types to HIR. This ensures that structure definitions embedded in
3947 * other structure definitions are processed.
3949 glsl_struct_field *const fields = ralloc_array(state, glsl_struct_field,
3953 foreach_list_typed (ast_declarator_list, decl_list, link,
3954 &this->declarations) {
3955 const char *type_name;
3957 decl_list->type->specifier->hir(instructions, state);
3959 /* Section 10.9 of the GLSL ES 1.00 specification states that
3960 * embedded structure definitions have been removed from the language.
3962 if (state->es_shader && decl_list->type->specifier->structure != NULL) {
3963 YYLTYPE loc = this->get_location();
3964 _mesa_glsl_error(&loc, state, "Embedded structure definitions are "
3965 "not allowed in GLSL ES 1.00.");
3968 const glsl_type *decl_type =
3969 decl_list->type->specifier->glsl_type(& type_name, state);
3971 foreach_list_typed (ast_declaration, decl, link,
3972 &decl_list->declarations) {
3973 const struct glsl_type *field_type = decl_type;
3974 if (decl->is_array) {
3975 YYLTYPE loc = decl->get_location();
3976 field_type = process_array_type(&loc, decl_type, decl->array_size,
3979 fields[i].type = (field_type != NULL)
3980 ? field_type : glsl_type::error_type;
3981 fields[i].name = decl->identifier;
3986 assert(i == decl_count);
3988 const glsl_type *t =
3989 glsl_type::get_record_instance(fields, decl_count, this->name);
3991 YYLTYPE loc = this->get_location();
3992 if (!state->symbols->add_type(name, t)) {
3993 _mesa_glsl_error(& loc, state, "struct `%s' previously defined", name);
3995 const glsl_type **s = reralloc(state, state->user_structures,
3997 state->num_user_structures + 1);
3999 s[state->num_user_structures] = t;
4000 state->user_structures = s;
4001 state->num_user_structures++;
4005 /* Structure type definitions do not have r-values.