/* * 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); } } else if (ir_dereference_record *deref_record = ir->as_dereference_record()) { /* There are two 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]). */ ir_dereference_variable *deref_var = deref_record->record->as_dereference_variable(); if (deref_var == NULL) { if (ir_dereference_array *deref_array = deref_record->record->as_dereference_array()) { deref_var = deref_array->array->as_dereference_variable(); } } if (deref_var != NULL) { if (deref_var->var->is_interface_instance()) { const glsl_type *interface_type = deref_var->var->get_interface_type(); unsigned field_index = deref_record->record->type->field_index(deref_record->field); assert(field_index < interface_type->length); if (idx > deref_var->var->max_ifc_array_access[field_index]) { deref_var->var->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); } } } } } 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->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; } }