summaryrefslogtreecommitdiffstats
path: root/src/compiler/glsl/ast_array_index.cpp
diff options
context:
space:
mode:
authorJason Ekstrand <[email protected]>2016-02-05 15:03:04 -0800
committerJason Ekstrand <[email protected]>2016-02-05 15:03:44 -0800
commit741744f691d6ef63e9f9a4c03136f969f2ffb0bf (patch)
tree7c9192a0648c2d90bb08efbc21ebcb7a6e2b873a /src/compiler/glsl/ast_array_index.cpp
parent9645b8eb1f1b79e537ad8ddb683507df7bc9da58 (diff)
parenteb63640c1d38a200a7b1540405051d3ff79d0d8a (diff)
Merge commit mesa-public/master into vulkan
This pulls in the patches that move all of the compiler stuff around
Diffstat (limited to 'src/compiler/glsl/ast_array_index.cpp')
-rw-r--r--src/compiler/glsl/ast_array_index.cpp333
1 files changed, 333 insertions, 0 deletions
diff --git a/src/compiler/glsl/ast_array_index.cpp b/src/compiler/glsl/ast_array_index.cpp
new file mode 100644
index 00000000000..f5baeb9ea32
--- /dev/null
+++ b/src/compiler/glsl/ast_array_index.cpp
@@ -0,0 +1,333 @@
+/*
+ * 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_index =
+ deref_record->record->type->field_index(deref_record->field);
+ assert(field_index < deref_var->var->get_interface_type()->length);
+
+ unsigned *const max_ifc_array_access =
+ deref_var->var->get_max_ifc_array_access();
+
+ assert(max_ifc_array_access != NULL);
+
+ if (idx > (int)max_ifc_array_access[field_index]) {
+ max_ifc_array_access[field_index] = 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(deref_record->field, 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();
+ 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 if (array->type->without_array()->is_interface()
+ && (array->variable_referenced()->data.mode == ir_var_uniform ||
+ 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."
+ */
+ _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.
+ */
+ if (array->type->without_array()->is_sampler()) {
+ if (!state->is_version(400, 0) && !state->ARB_gpu_shader5_enable) {
+ 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;
+ }
+}