/*
* 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 "compiler/glsl_types.h"
#include "ir.h"
void
ast_array_specifier::print(void) const
{
foreach_list_typed (ast_node, array_dimension, link, &this->array_dimensions) {
printf("[ ");
if (((ast_expression*)array_dimension)->oper != ast_unsized_array_dim)
array_dimension->print();
printf("] ");
}
}
/**
* 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, int 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 > (int)var->data.max_array_access) {
var->data.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);
}
} else if (ir_dereference_record *deref_record =
ir->as_dereference_record()) {
/* There are three possibilities we need to consider:
*
* - Accessing an element of an array that is a member of a named
* interface block (e.g. ifc.foo[i])
*
* - Accessing an element of an array that is a member of a named
* interface block array (e.g. ifc[j].foo[i]).
*
* - Accessing an element of an array that is a member of a named
* interface block array of arrays (e.g. ifc[j][k].foo[i]).
*/
ir_dereference_variable *deref_var =
deref_record->record->as_dereference_variable();
if (deref_var == NULL) {
ir_dereference_array *deref_array =
deref_record->record->as_dereference_array();
ir_dereference_array *deref_array_prev = NULL;
while (deref_array != NULL) {
deref_array_prev = deref_array;
deref_array = deref_array->array->as_dereference_array();
}
if (deref_array_prev != NULL)
deref_var = deref_array_prev->array->as_dereference_variable();
}
if (deref_var != NULL) {
if (deref_var->var->is_interface_instance()) {
unsigned field_idx = deref_record->field_idx;
assert(field_idx < deref_var->var->get_interface_type()->length);
int *const max_ifc_array_access =
deref_var->var->get_max_ifc_array_access();
assert(max_ifc_array_access != NULL);
if (idx > max_ifc_array_access[field_idx]) {
max_ifc_array_access[field_idx] = idx;
/* Check whether this access will, as a side effect, implicitly
* cause the size of a built-in array to be too large.
*/
const char *field_name =
deref_record->record->type->fields.structure[field_idx].name;
check_builtin_array_max_size(field_name, idx+1, *loc, state);
}
}
}
}
}
static int
get_implicit_array_size(struct _mesa_glsl_parse_state *state,
ir_rvalue *array)
{
ir_variable *var = array->variable_referenced();
/* Inputs in control shader are implicitly sized
* to the maximum patch size.
*/
if (state->stage == MESA_SHADER_TESS_CTRL &&
var->data.mode == ir_var_shader_in) {
return state->Const.MaxPatchVertices;
}
/* Non-patch inputs in evaluation shader are implicitly sized
* to the maximum patch size.
*/
if (state->stage == MESA_SHADER_TESS_EVAL &&
var->data.mode == ir_var_shader_in &&
!var->data.patch) {
return state->Const.MaxPatchVertices;
}
return 0;
}
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(mem_ctx);
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 -1 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->is_unsized_array()) {
int implicit_size = get_implicit_array_size(state, array);
if (implicit_size) {
ir_variable *v = array->whole_variable_referenced();
if (v != NULL)
v->data.max_array_access = implicit_size - 1;
}
else if (state->stage == MESA_SHADER_TESS_CTRL &&
array->variable_referenced()->data.mode == ir_var_shader_out &&
!array->variable_referenced()->data.patch) {
/* Tessellation control shader output non-patch arrays are
* initially unsized. Despite that, they are allowed to be
* indexed with a non-constant expression (typically
* "gl_InvocationID"). The array size will be determined
* by the linker.
*/
}
else if (array->variable_referenced()->data.mode !=
ir_var_shader_storage) {
_mesa_glsl_error(&loc, state, "unsized array index must be constant");
} else {
/* Unsized array non-constant indexing on SSBO is allowed only for
* the last member of the SSBO definition.
*/
ir_variable *var = array->variable_referenced();
const glsl_type *iface_type = var->get_interface_type();
int field_index = iface_type->field_index(var->name);
/* Field index can be < 0 for instance arrays */
if (field_index >= 0 &&
field_index != (int) iface_type->length - 1) {
_mesa_glsl_error(&loc, state, "Indirect access on unsized "
"array is limited to the last member of "
"SSBO.");
}
}
} else if (array->type->without_array()->is_interface()
&& ((array->variable_referenced()->data.mode == ir_var_uniform
&& !state->is_version(400, 320)
&& !state->ARB_gpu_shader5_enable
&& !state->EXT_gpu_shader5_enable
&& !state->OES_gpu_shader5_enable) ||
(array->variable_referenced()->data.mode == ir_var_shader_storage
&& !state->is_version(400, 0)
&& !state->ARB_gpu_shader5_enable))) {
/* Page 50 in section 4.3.9 of the OpenGL ES 3.10 spec says:
*
* "All indices used to index a uniform or shader storage block
* array must be constant integral expressions."
*
* But OES_gpu_shader5 (and ESSL 3.20) relax this to allow indexing
* on uniform blocks but not shader storage blocks.
*
*/
_mesa_glsl_error(&loc, state, "%s block array index must be constant",
array->variable_referenced()->data.mode
== ir_var_uniform ? "uniform" : "shader storage");
} 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->data.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.
*
* In GLSL 4.00 / ARB_gpu_shader5, this requirement is relaxed again to allow
* indexing with dynamically uniform expressions. Note that these are not
* required to be uniforms or expressions based on them, but merely that the
* values must not diverge between shader invocations run together. If the
* values *do* diverge, then the behavior of the operation requiring a
* dynamically uniform expression is undefined.
*
* From section 4.1.7 of the ARB_bindless_texture spec:
*
* "Samplers aggregated into arrays within a shader (using square
* brackets []) can be indexed with arbitrary integer expressions."
*/
if (array->type->without_array()->is_sampler()) {
if (!state->is_version(400, 320) &&
!state->ARB_gpu_shader5_enable &&
!state->EXT_gpu_shader5_enable &&
!state->OES_gpu_shader5_enable &&
!state->has_bindless()) {
if (state->is_version(130, 300))
_mesa_glsl_error(&loc, state,
"sampler arrays indexed with non-constant "
"expressions are forbidden in GLSL %s "
"and later",
state->es_shader ? "ES 3.00" : "1.30");
else if (state->es_shader)
_mesa_glsl_warning(&loc, state,
"sampler arrays indexed with non-constant "
"expressions will be forbidden in GLSL "
"3.00 and later");
else
_mesa_glsl_warning(&loc, state,
"sampler arrays indexed with non-constant "
"expressions will be forbidden in GLSL "
"1.30 and later");
}
}
/* From page 27 of the GLSL ES 3.1 specification:
*
* "When aggregated into arrays within a shader, images can only be
* indexed with a constant integral expression."
*
* On the other hand the desktop GL specification extension allows
* non-constant indexing of image arrays, but behavior is left undefined
* in cases where the indexing expression is not dynamically uniform.
*/
if (state->es_shader && array->type->without_array()->is_image()) {
_mesa_glsl_error(&loc, state,
"image arrays indexed with non-constant "
"expressions are forbidden in GLSL ES.");
}
}
/* After performing all of the error checking, generate the IR for the
* expression.
*/
if (array->type->is_array()
|| array->type->is_matrix()
|| array->type->is_vector()) {
return new(mem_ctx) ir_dereference_array(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;
}
}