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/*
* Copyright © 2010 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include "ast.h"
#include "glsl_types.h"
#include "ir.h"
/**
* If \c ir is a reference to an array for which we are tracking the max array
* element accessed, track that the given element has been accessed.
* Otherwise do nothing.
*
* This function also checks whether the array is a built-in array whose
* maximum size is too small to accommodate the given index, and if so uses
* loc and state to report the error.
*/
static void
update_max_array_access(ir_rvalue *ir, unsigned idx, YYLTYPE *loc,
struct _mesa_glsl_parse_state *state)
{
if (ir_dereference_variable *deref_var = ir->as_dereference_variable()) {
ir_variable *var = deref_var->var;
if (idx > var->max_array_access) {
var->max_array_access = idx;
/* Check whether this access will, as a side effect, implicitly cause
* the size of a built-in array to be too large.
*/
check_builtin_array_max_size(var->name, idx+1, *loc, state);
}
}
}
ir_rvalue *
_mesa_ast_array_index_to_hir(void *mem_ctx,
struct _mesa_glsl_parse_state *state,
ir_rvalue *array, ir_rvalue *idx,
YYLTYPE &loc, YYLTYPE &idx_loc)
{
if (!array->type->is_error()
&& !array->type->is_array()
&& !array->type->is_matrix()
&& !array->type->is_vector()) {
_mesa_glsl_error(& idx_loc, state,
"cannot dereference non-array / non-matrix / "
"non-vector");
}
if (!idx->type->is_error()) {
if (!idx->type->is_integer()) {
_mesa_glsl_error(& idx_loc, state, "array index must be integer type");
} else if (!idx->type->is_scalar()) {
_mesa_glsl_error(& idx_loc, state, "array index must be scalar");
}
}
/* If the array index is a constant expression and the array has a
* declared size, ensure that the access is in-bounds. If the array
* index is not a constant expression, ensure that the array has a
* declared size.
*/
ir_constant *const const_index = idx->constant_expression_value();
if (const_index != NULL && idx->type->is_integer()) {
const int idx = const_index->value.i[0];
const char *type_name = "error";
unsigned bound = 0;
/* From page 24 (page 30 of the PDF) of the GLSL 1.50 spec:
*
* "It is illegal to declare an array with a size, and then
* later (in the same shader) index the same array with an
* integral constant expression greater than or equal to the
* declared size. It is also illegal to index an array with a
* negative constant expression."
*/
if (array->type->is_matrix()) {
if (array->type->row_type()->vector_elements <= idx) {
type_name = "matrix";
bound = array->type->row_type()->vector_elements;
}
} else if (array->type->is_vector()) {
if (array->type->vector_elements <= idx) {
type_name = "vector";
bound = array->type->vector_elements;
}
} else {
/* glsl_type::array_size() returns 0 for non-array types. This means
* that we don't need to verify that the type is an array before
* doing the bounds checking.
*/
if ((array->type->array_size() > 0)
&& (array->type->array_size() <= idx)) {
type_name = "array";
bound = array->type->array_size();
}
}
if (bound > 0) {
_mesa_glsl_error(& loc, state, "%s index must be < %u",
type_name, bound);
} else if (idx < 0) {
_mesa_glsl_error(& loc, state, "%s index must be >= 0",
type_name);
}
if (array->type->is_array())
update_max_array_access(array, idx, &loc, state);
} else if (const_index == NULL && array->type->is_array()) {
if (array->type->array_size() == 0) {
_mesa_glsl_error(&loc, state, "unsized array index must be constant");
} else if (array->type->fields.array->is_interface()
&& array->variable_referenced()->mode == ir_var_uniform) {
/* Page 46 in section 4.3.7 of the OpenGL ES 3.00 spec says:
*
* "All indexes used to index a uniform block array must be
* constant integral expressions."
*/
_mesa_glsl_error(&loc, state,
"uniform block array index must be constant");
} else {
/* whole_variable_referenced can return NULL if the array is a
* member of a structure. In this case it is safe to not update
* the max_array_access field because it is never used for fields
* of structures.
*/
ir_variable *v = array->whole_variable_referenced();
if (v != NULL)
v->max_array_access = array->type->array_size() - 1;
}
/* From page 23 (29 of the PDF) of the GLSL 1.30 spec:
*
* "Samplers aggregated into arrays within a shader (using square
* brackets [ ]) can only be indexed with integral constant
* expressions [...]."
*
* This restriction was added in GLSL 1.30. Shaders using earlier
* version of the language should not be rejected by the compiler
* front-end for using this construct. This allows useful things such
* as using a loop counter as the index to an array of samplers. If the
* loop in unrolled, the code should compile correctly. Instead, emit a
* warning.
*/
if (array->type->element_type()->is_sampler()) {
if (!state->is_version(130, 100)) {
if (state->es_shader) {
_mesa_glsl_warning(&loc, state,
"sampler arrays indexed with non-constant "
"expressions is optional in %s",
state->get_version_string());
} else {
_mesa_glsl_warning(&loc, state,
"sampler arrays indexed with non-constant "
"expressions will be forbidden in GLSL 1.30 "
"and later");
}
} else {
_mesa_glsl_error(&loc, state,
"sampler arrays indexed with non-constant "
"expressions is forbidden in GLSL 1.30 and "
"later");
}
}
}
/* After performing all of the error checking, generate the IR for the
* expression.
*/
if (array->type->is_array()
|| array->type->is_matrix()) {
return new(mem_ctx) ir_dereference_array(array, idx);
} else if (array->type->is_vector()) {
return new(mem_ctx) ir_expression(ir_binop_vector_extract, array, idx);
} else if (array->type->is_error()) {
return array;
} else {
ir_rvalue *result = new(mem_ctx) ir_dereference_array(array, idx);
result->type = glsl_type::error_type;
return result;
}
}
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