1 /* 2 * Copyright 2010 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 21 * DEALINGS IN THE SOFTWARE. 22 */ 23 24 #include "glsl_types.h" 25 #include "ir.h" 26 27 int 28 type_compare(const glsl_type *a, const glsl_type *b) 29 { 30 /* If the types are the same, they trivially match. 31 */ 32 if (a == b) 33 return 0; 34 35 switch (a->base_type) { 36 case GLSL_TYPE_UINT: 37 case GLSL_TYPE_INT: 38 case GLSL_TYPE_BOOL: 39 /* There is no implicit conversion to or from integer types or bool. 40 */ 41 if ((a->is_integer() != b->is_integer()) 42 || (a->is_boolean() != b->is_boolean())) 43 return -1; 44 45 /* FALLTHROUGH */ 46 47 case GLSL_TYPE_FLOAT: 48 if ((a->vector_elements != b->vector_elements) 49 || (a->matrix_columns != b->matrix_columns)) 50 return -1; 51 52 return 1; 53 54 case GLSL_TYPE_SAMPLER: 55 case GLSL_TYPE_STRUCT: 56 /* Samplers and structures must match exactly. 57 */ 58 return -1; 59 60 case GLSL_TYPE_ARRAY: 61 if ((b->base_type != GLSL_TYPE_ARRAY) 62 || (a->length != b->length)) 63 return -1; 64 65 /* From GLSL 1.50 spec, page 27 (page 33 of the PDF): 66 * "There are no implicit array or structure conversions." 67 * 68 * If the comparison of the array element types detects that a conversion 69 * would be required, the array types do not match. 70 */ 71 return (type_compare(a->fields.array, b->fields.array) == 0) ? 0 : -1; 72 73 case GLSL_TYPE_VOID: 74 case GLSL_TYPE_ERROR: 75 default: 76 /* These are all error conditions. It is invalid for a parameter to 77 * a function to be declared as error, void, or a function. 78 */ 79 return -1; 80 } 81 82 /* This point should be unreachable. 83 */ 84 assert(0); 85 } 86 87 88 static int 89 parameter_lists_match(const exec_list *list_a, const exec_list *list_b) 90 { 91 const exec_node *node_a = list_a->head; 92 const exec_node *node_b = list_b->head; 93 int total_score = 0; 94 95 for (/* empty */ 96 ; !node_a->is_tail_sentinel() 97 ; node_a = node_a->next, node_b = node_b->next) { 98 /* If all of the parameters from the other parameter list have been 99 * exhausted, the lists have different length and, by definition, 100 * do not match. 101 */ 102 if (node_b->is_tail_sentinel()) 103 return -1; 104 105 106 const ir_variable *const param = (ir_variable *) node_a; 107 const ir_instruction *const actual = (ir_instruction *) node_b; 108 109 /* Determine whether or not the types match. If the types are an 110 * exact match, the match score is zero. If the types don't match 111 * but the actual parameter can be coerced to the type of the declared 112 * parameter, the match score is one. 113 */ 114 int score; 115 switch ((enum ir_variable_mode)(param->mode)) { 116 case ir_var_auto: 117 case ir_var_uniform: 118 case ir_var_temporary: 119 /* These are all error conditions. It is invalid for a parameter to 120 * a function to be declared as auto (not in, out, or inout) or 121 * as uniform. 122 */ 123 assert(0); 124 return -1; 125 126 case ir_var_in: 127 score = type_compare(param->type, actual->type); 128 break; 129 130 case ir_var_out: 131 score = type_compare(actual->type, param->type); 132 break; 133 134 case ir_var_inout: 135 /* Since there are no bi-directional automatic conversions (e.g., 136 * there is int -> float but no float -> int), inout parameters must 137 * be exact matches. 138 */ 139 score = (type_compare(actual->type, param->type) == 0) ? 0 : -1; 140 break; 141 142 default: 143 assert(false); 144 } 145 146 if (score < 0) 147 return -1; 148 149 total_score += score; 150 } 151 152 /* If all of the parameters from the other parameter list have been 153 * exhausted, the lists have different length and, by definition, do not 154 * match. 155 */ 156 if (!node_b->is_tail_sentinel()) 157 return -1; 158 159 return total_score; 160 } 161 162 163 ir_function_signature * 164 ir_function::matching_signature(const exec_list *actual_parameters) 165 { 166 ir_function_signature *match = NULL; 167 168 foreach_iter(exec_list_iterator, iter, signatures) { 169 ir_function_signature *const sig = 170 (ir_function_signature *) iter.get(); 171 172 const int score = parameter_lists_match(& sig->parameters, 173 actual_parameters); 174 175 if (score == 0) 176 return sig; 177 178 if (score > 0) { 179 if (match != NULL) 180 return NULL; 181 182 match = sig; 183 } 184 } 185 186 return match; 187 } 188 189 190 static bool 191 parameter_lists_match_exact(const exec_list *list_a, const exec_list *list_b) 192 { 193 const exec_node *node_a = list_a->head; 194 const exec_node *node_b = list_b->head; 195 196 for (/* empty */ 197 ; !node_a->is_tail_sentinel() && !node_b->is_tail_sentinel() 198 ; node_a = node_a->next, node_b = node_b->next) { 199 ir_variable *a = (ir_variable *) node_a; 200 ir_variable *b = (ir_variable *) node_b; 201 202 /* If the types of the parameters do not match, the parameters lists 203 * are different. 204 */ 205 if (a->type != b->type) 206 return false; 207 } 208 209 /* Unless both lists are exhausted, they differ in length and, by 210 * definition, do not match. 211 */ 212 return (node_a->is_tail_sentinel() == node_b->is_tail_sentinel()); 213 } 214 215 ir_function_signature * 216 ir_function::exact_matching_signature(const exec_list *actual_parameters) 217 { 218 foreach_iter(exec_list_iterator, iter, signatures) { 219 ir_function_signature *const sig = 220 (ir_function_signature *) iter.get(); 221 222 if (parameter_lists_match_exact(&sig->parameters, actual_parameters)) 223 return sig; 224 } 225 return NULL; 226 } 227