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15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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21 * DEALINGS IN THE SOFTWARE.
25 #include "glsl_types.h"
29 ast_array_specifier::print(void) const
31 if (this->is_unsized_array) {
35 foreach_list_typed (ast_node, array_dimension, link, &this->array_dimensions) {
37 array_dimension->print();
43 * If \c ir is a reference to an array for which we are tracking the max array
44 * element accessed, track that the given element has been accessed.
45 * Otherwise do nothing.
47 * This function also checks whether the array is a built-in array whose
48 * maximum size is too small to accommodate the given index, and if so uses
49 * loc and state to report the error.
52 update_max_array_access(ir_rvalue *ir, int idx, YYLTYPE *loc,
53 struct _mesa_glsl_parse_state *state)
55 if (ir_dereference_variable *deref_var = ir->as_dereference_variable()) {
56 ir_variable *var = deref_var->var;
57 if (idx > (int)var->data.max_array_access) {
58 var->data.max_array_access = idx;
60 /* Check whether this access will, as a side effect, implicitly cause
61 * the size of a built-in array to be too large.
63 check_builtin_array_max_size(var->name, idx+1, *loc, state);
65 } else if (ir_dereference_record *deref_record =
66 ir->as_dereference_record()) {
67 /* There are two possibilities we need to consider:
69 * - Accessing an element of an array that is a member of a named
70 * interface block (e.g. ifc.foo[i])
72 * - Accessing an element of an array that is a member of a named
73 * interface block array (e.g. ifc[j].foo[i]).
75 ir_dereference_variable *deref_var =
76 deref_record->record->as_dereference_variable();
77 if (deref_var == NULL) {
78 if (ir_dereference_array *deref_array =
79 deref_record->record->as_dereference_array()) {
80 deref_var = deref_array->array->as_dereference_variable();
84 if (deref_var != NULL) {
85 if (deref_var->var->is_interface_instance()) {
86 unsigned field_index =
87 deref_record->record->type->field_index(deref_record->field);
88 assert(field_index < deref_var->var->get_interface_type()->length);
90 unsigned *const max_ifc_array_access =
91 deref_var->var->get_max_ifc_array_access();
93 assert(max_ifc_array_access != NULL);
95 if (idx > (int)max_ifc_array_access[field_index]) {
96 max_ifc_array_access[field_index] = idx;
98 /* Check whether this access will, as a side effect, implicitly
99 * cause the size of a built-in array to be too large.
101 check_builtin_array_max_size(deref_record->field, idx+1, *loc,
111 _mesa_ast_array_index_to_hir(void *mem_ctx,
112 struct _mesa_glsl_parse_state *state,
113 ir_rvalue *array, ir_rvalue *idx,
114 YYLTYPE &loc, YYLTYPE &idx_loc)
116 if (!array->type->is_error()
117 && !array->type->is_array()
118 && !array->type->is_matrix()
119 && !array->type->is_vector()) {
120 _mesa_glsl_error(& idx_loc, state,
121 "cannot dereference non-array / non-matrix / "
125 if (!idx->type->is_error()) {
126 if (!idx->type->is_integer()) {
127 _mesa_glsl_error(& idx_loc, state, "array index must be integer type");
128 } else if (!idx->type->is_scalar()) {
129 _mesa_glsl_error(& idx_loc, state, "array index must be scalar");
133 /* If the array index is a constant expression and the array has a
134 * declared size, ensure that the access is in-bounds. If the array
135 * index is not a constant expression, ensure that the array has a
138 ir_constant *const const_index = idx->constant_expression_value();
139 if (const_index != NULL && idx->type->is_integer()) {
140 const int idx = const_index->value.i[0];
141 const char *type_name = "error";
144 /* From page 24 (page 30 of the PDF) of the GLSL 1.50 spec:
146 * "It is illegal to declare an array with a size, and then
147 * later (in the same shader) index the same array with an
148 * integral constant expression greater than or equal to the
149 * declared size. It is also illegal to index an array with a
150 * negative constant expression."
152 if (array->type->is_matrix()) {
153 if (array->type->row_type()->vector_elements <= idx) {
154 type_name = "matrix";
155 bound = array->type->row_type()->vector_elements;
157 } else if (array->type->is_vector()) {
158 if (array->type->vector_elements <= idx) {
159 type_name = "vector";
160 bound = array->type->vector_elements;
163 /* glsl_type::array_size() returns -1 for non-array types. This means
164 * that we don't need to verify that the type is an array before
165 * doing the bounds checking.
167 if ((array->type->array_size() > 0)
168 && (array->type->array_size() <= idx)) {
170 bound = array->type->array_size();
175 _mesa_glsl_error(& loc, state, "%s index must be < %u",
177 } else if (idx < 0) {
178 _mesa_glsl_error(& loc, state, "%s index must be >= 0",
182 if (array->type->is_array())
183 update_max_array_access(array, idx, &loc, state);
184 } else if (const_index == NULL && array->type->is_array()) {
185 if (array->type->is_unsized_array()) {
186 _mesa_glsl_error(&loc, state, "unsized array index must be constant");
187 } else if (array->type->fields.array->is_interface()
188 && array->variable_referenced()->data.mode == ir_var_uniform
189 && !state->is_version(400, 0) && !state->ARB_gpu_shader5_enable) {
190 /* Page 46 in section 4.3.7 of the OpenGL ES 3.00 spec says:
192 * "All indexes used to index a uniform block array must be
193 * constant integral expressions."
195 _mesa_glsl_error(&loc, state,
196 "uniform block array index must be constant");
198 /* whole_variable_referenced can return NULL if the array is a
199 * member of a structure. In this case it is safe to not update
200 * the max_array_access field because it is never used for fields
203 ir_variable *v = array->whole_variable_referenced();
205 v->data.max_array_access = array->type->array_size() - 1;
208 /* From page 23 (29 of the PDF) of the GLSL 1.30 spec:
210 * "Samplers aggregated into arrays within a shader (using square
211 * brackets [ ]) can only be indexed with integral constant
212 * expressions [...]."
214 * This restriction was added in GLSL 1.30. Shaders using earlier
215 * version of the language should not be rejected by the compiler
216 * front-end for using this construct. This allows useful things such
217 * as using a loop counter as the index to an array of samplers. If the
218 * loop in unrolled, the code should compile correctly. Instead, emit a
221 * In GLSL 4.00 / ARB_gpu_shader5, this requirement is relaxed again to allow
222 * indexing with dynamically uniform expressions. Note that these are not
223 * required to be uniforms or expressions based on them, but merely that the
224 * values must not diverge between shader invocations run together. If the
225 * values *do* diverge, then the behavior of the operation requiring a
226 * dynamically uniform expression is undefined.
228 if (array->type->without_array()->is_sampler()) {
229 if (!state->is_version(400, 0) && !state->ARB_gpu_shader5_enable) {
230 if (state->is_version(130, 300))
231 _mesa_glsl_error(&loc, state,
232 "sampler arrays indexed with non-constant "
233 "expressions are forbidden in GLSL %s "
235 state->es_shader ? "ES 3.00" : "1.30");
236 else if (state->es_shader)
237 _mesa_glsl_warning(&loc, state,
238 "sampler arrays indexed with non-constant "
239 "expressions will be forbidden in GLSL "
242 _mesa_glsl_warning(&loc, state,
243 "sampler arrays indexed with non-constant "
244 "expressions will be forbidden in GLSL "
250 /* After performing all of the error checking, generate the IR for the
253 if (array->type->is_array()
254 || array->type->is_matrix()) {
255 return new(mem_ctx) ir_dereference_array(array, idx);
256 } else if (array->type->is_vector()) {
257 return new(mem_ctx) ir_expression(ir_binop_vector_extract, array, idx);
258 } else if (array->type->is_error()) {
261 ir_rvalue *result = new(mem_ctx) ir_dereference_array(array, idx);
262 result->type = glsl_type::error_type;