| /* |
| * 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 "compiler/glsl_types.h" |
| #include "ir.h" |
| #include "glsl_parser_extras.h" |
| #include "main/errors.h" |
| |
| typedef enum { |
| PARAMETER_LIST_NO_MATCH, |
| PARAMETER_LIST_EXACT_MATCH, |
| PARAMETER_LIST_INEXACT_MATCH /*< Match requires implicit conversion. */ |
| } parameter_list_match_t; |
| |
| /** |
| * \brief Check if two parameter lists match. |
| * |
| * \param list_a Parameters of the function definition. |
| * \param list_b Actual parameters passed to the function. |
| * \see matching_signature() |
| */ |
| static parameter_list_match_t |
| parameter_lists_match(_mesa_glsl_parse_state *state, |
| const exec_list *list_a, const exec_list *list_b) |
| { |
| const exec_node *node_a = list_a->get_head_raw(); |
| const exec_node *node_b = list_b->get_head_raw(); |
| |
| /* This is set to true if there is an inexact match requiring an implicit |
| * conversion. */ |
| bool inexact_match = false; |
| |
| for (/* empty */ |
| ; !node_a->is_tail_sentinel() |
| ; node_a = node_a->next, node_b = node_b->next) { |
| /* If all of the parameters from the other parameter list have been |
| * exhausted, the lists have different length and, by definition, |
| * do not match. |
| */ |
| if (node_b->is_tail_sentinel()) |
| return PARAMETER_LIST_NO_MATCH; |
| |
| |
| const ir_variable *const param = (ir_variable *) node_a; |
| const ir_rvalue *const actual = (ir_rvalue *) node_b; |
| |
| if (param->type == actual->type) |
| continue; |
| |
| /* Try to find an implicit conversion from actual to param. */ |
| inexact_match = true; |
| switch ((enum ir_variable_mode)(param->data.mode)) { |
| case ir_var_auto: |
| case ir_var_uniform: |
| case ir_var_shader_storage: |
| case ir_var_temporary: |
| /* These are all error conditions. It is invalid for a parameter to |
| * a function to be declared as auto (not in, out, or inout) or |
| * as uniform. |
| */ |
| assert(0); |
| return PARAMETER_LIST_NO_MATCH; |
| |
| case ir_var_const_in: |
| case ir_var_function_in: |
| if (!actual->type->can_implicitly_convert_to(param->type, state)) |
| return PARAMETER_LIST_NO_MATCH; |
| break; |
| |
| case ir_var_function_out: |
| if (!param->type->can_implicitly_convert_to(actual->type, state)) |
| return PARAMETER_LIST_NO_MATCH; |
| break; |
| |
| case ir_var_function_inout: |
| /* Since there are no bi-directional automatic conversions (e.g., |
| * there is int -> float but no float -> int), inout parameters must |
| * be exact matches. |
| */ |
| return PARAMETER_LIST_NO_MATCH; |
| |
| default: |
| assert(false); |
| return PARAMETER_LIST_NO_MATCH; |
| } |
| } |
| |
| /* If all of the parameters from the other parameter list have been |
| * exhausted, the lists have different length and, by definition, do not |
| * match. |
| */ |
| if (!node_b->is_tail_sentinel()) |
| return PARAMETER_LIST_NO_MATCH; |
| |
| if (inexact_match) |
| return PARAMETER_LIST_INEXACT_MATCH; |
| else |
| return PARAMETER_LIST_EXACT_MATCH; |
| } |
| |
| |
| /* Classes of parameter match, sorted (mostly) best matches first. |
| * See is_better_parameter_match() below for the exceptions. |
| * */ |
| typedef enum { |
| PARAMETER_EXACT_MATCH, |
| PARAMETER_FLOAT_TO_DOUBLE, |
| PARAMETER_INT_TO_FLOAT, |
| PARAMETER_INT_TO_DOUBLE, |
| PARAMETER_OTHER_CONVERSION, |
| } parameter_match_t; |
| |
| |
| static parameter_match_t |
| get_parameter_match_type(const ir_variable *param, |
| const ir_rvalue *actual) |
| { |
| const glsl_type *from_type; |
| const glsl_type *to_type; |
| |
| if (param->data.mode == ir_var_function_out) { |
| from_type = param->type; |
| to_type = actual->type; |
| } else { |
| from_type = actual->type; |
| to_type = param->type; |
| } |
| |
| if (from_type == to_type) |
| return PARAMETER_EXACT_MATCH; |
| |
| if (to_type->is_double()) { |
| if (from_type->is_float()) |
| return PARAMETER_FLOAT_TO_DOUBLE; |
| return PARAMETER_INT_TO_DOUBLE; |
| } |
| |
| if (to_type->is_float()) |
| return PARAMETER_INT_TO_FLOAT; |
| |
| /* int -> uint and any other oddball conversions */ |
| return PARAMETER_OTHER_CONVERSION; |
| } |
| |
| |
| static bool |
| is_better_parameter_match(parameter_match_t a_match, |
| parameter_match_t b_match) |
| { |
| /* From section 6.1 of the GLSL 4.00 spec (and the ARB_gpu_shader5 spec): |
| * |
| * 1. An exact match is better than a match involving any implicit |
| * conversion. |
| * |
| * 2. A match involving an implicit conversion from float to double |
| * is better than match involving any other implicit conversion. |
| * |
| * [XXX: Not in GLSL 4.0: Only in ARB_gpu_shader5: |
| * 3. A match involving an implicit conversion from either int or uint |
| * to float is better than a match involving an implicit conversion |
| * from either int or uint to double.] |
| * |
| * If none of the rules above apply to a particular pair of conversions, |
| * neither conversion is considered better than the other. |
| * |
| * -- |
| * |
| * Notably, the int->uint conversion is *not* considered to be better |
| * or worse than int/uint->float or int/uint->double. |
| */ |
| |
| if (a_match >= PARAMETER_INT_TO_FLOAT && b_match == PARAMETER_OTHER_CONVERSION) |
| return false; |
| |
| return a_match < b_match; |
| } |
| |
| |
| static bool |
| is_best_inexact_overload(const exec_list *actual_parameters, |
| ir_function_signature **matches, |
| int num_matches, |
| ir_function_signature *sig) |
| { |
| /* From section 6.1 of the GLSL 4.00 spec (and the ARB_gpu_shader5 spec): |
| * |
| * "A function definition A is considered a better |
| * match than function definition B if: |
| * |
| * * for at least one function argument, the conversion for that argument |
| * in A is better than the corresponding conversion in B; and |
| * |
| * * there is no function argument for which the conversion in B is better |
| * than the corresponding conversion in A. |
| * |
| * If a single function definition is considered a better match than every |
| * other matching function definition, it will be used. Otherwise, a |
| * semantic error occurs and the shader will fail to compile." |
| */ |
| for (ir_function_signature **other = matches; |
| other < matches + num_matches; other++) { |
| if (*other == sig) |
| continue; |
| |
| const exec_node *node_a = sig->parameters.get_head_raw(); |
| const exec_node *node_b = (*other)->parameters.get_head_raw(); |
| const exec_node *node_p = actual_parameters->get_head_raw(); |
| |
| bool better_for_some_parameter = false; |
| |
| for (/* empty */ |
| ; !node_a->is_tail_sentinel() |
| ; node_a = node_a->next, |
| node_b = node_b->next, |
| node_p = node_p->next) { |
| parameter_match_t a_match = get_parameter_match_type( |
| (const ir_variable *)node_a, |
| (const ir_rvalue *)node_p); |
| parameter_match_t b_match = get_parameter_match_type( |
| (const ir_variable *)node_b, |
| (const ir_rvalue *)node_p); |
| |
| if (is_better_parameter_match(a_match, b_match)) |
| better_for_some_parameter = true; |
| |
| if (is_better_parameter_match(b_match, a_match)) |
| return false; /* B is better for this parameter */ |
| } |
| |
| if (!better_for_some_parameter) |
| return false; /* A must be better than B for some parameter */ |
| |
| } |
| |
| return true; |
| } |
| |
| |
| static ir_function_signature * |
| choose_best_inexact_overload(_mesa_glsl_parse_state *state, |
| const exec_list *actual_parameters, |
| ir_function_signature **matches, |
| int num_matches) |
| { |
| if (num_matches == 0) |
| return NULL; |
| |
| if (num_matches == 1) |
| return *matches; |
| |
| /* Without GLSL 4.0, ARB_gpu_shader5, or MESA_shader_integer_functions, |
| * there is no overload resolution among multiple inexact matches. Note |
| * that state may be NULL here if called from the linker; in that case we |
| * assume everything supported in any GLSL version is available. |
| */ |
| if (!state || state->is_version(400, 0) || state->ARB_gpu_shader5_enable || |
| state->MESA_shader_integer_functions_enable || |
| state->EXT_shader_implicit_conversions_enable) { |
| for (ir_function_signature **sig = matches; sig < matches + num_matches; sig++) { |
| if (is_best_inexact_overload(actual_parameters, matches, num_matches, *sig)) |
| return *sig; |
| } |
| } |
| |
| return NULL; /* no best candidate */ |
| } |
| |
| |
| ir_function_signature * |
| ir_function::matching_signature(_mesa_glsl_parse_state *state, |
| const exec_list *actual_parameters, |
| bool allow_builtins) |
| { |
| bool is_exact; |
| return matching_signature(state, actual_parameters, allow_builtins, |
| &is_exact); |
| } |
| |
| ir_function_signature * |
| ir_function::matching_signature(_mesa_glsl_parse_state *state, |
| const exec_list *actual_parameters, |
| bool allow_builtins, |
| bool *is_exact) |
| { |
| ir_function_signature **inexact_matches = NULL; |
| ir_function_signature **inexact_matches_temp; |
| ir_function_signature *match = NULL; |
| int num_inexact_matches = 0; |
| |
| /* From page 42 (page 49 of the PDF) of the GLSL 1.20 spec: |
| * |
| * "If an exact match is found, the other signatures are ignored, and |
| * the exact match is used. Otherwise, if no exact match is found, then |
| * the implicit conversions in Section 4.1.10 "Implicit Conversions" will |
| * be applied to the calling arguments if this can make their types match |
| * a signature. In this case, it is a semantic error if there are |
| * multiple ways to apply these conversions to the actual arguments of a |
| * call such that the call can be made to match multiple signatures." |
| */ |
| foreach_in_list(ir_function_signature, sig, &this->signatures) { |
| /* Skip over any built-ins that aren't available in this shader. */ |
| if (sig->is_builtin() && (!allow_builtins || |
| !sig->is_builtin_available(state))) |
| continue; |
| |
| switch (parameter_lists_match(state, & sig->parameters, actual_parameters)) { |
| case PARAMETER_LIST_EXACT_MATCH: |
| *is_exact = true; |
| free(inexact_matches); |
| return sig; |
| case PARAMETER_LIST_INEXACT_MATCH: |
| /* Subroutine signatures must match exactly */ |
| if (this->is_subroutine) |
| continue; |
| inexact_matches_temp = (ir_function_signature **) |
| realloc(inexact_matches, |
| sizeof(*inexact_matches) * |
| (num_inexact_matches + 1)); |
| if (inexact_matches_temp == NULL) { |
| _mesa_error_no_memory(__func__); |
| free(inexact_matches); |
| return NULL; |
| } |
| inexact_matches = inexact_matches_temp; |
| inexact_matches[num_inexact_matches++] = sig; |
| continue; |
| case PARAMETER_LIST_NO_MATCH: |
| continue; |
| default: |
| assert(false); |
| return NULL; |
| } |
| } |
| |
| /* There is no exact match (we would have returned it by now). If there |
| * are multiple inexact matches, the call is ambiguous, which is an error. |
| * |
| * FINISHME: Report a decent error. Returning NULL will likely result in |
| * FINISHME: a "no matching signature" error; it should report that the |
| * FINISHME: call is ambiguous. But reporting errors from here is hard. |
| */ |
| *is_exact = false; |
| |
| match = choose_best_inexact_overload(state, actual_parameters, |
| inexact_matches, num_inexact_matches); |
| |
| free(inexact_matches); |
| return match; |
| } |
| |
| |
| static bool |
| parameter_lists_match_exact(const exec_list *list_a, const exec_list *list_b) |
| { |
| const exec_node *node_a = list_a->get_head_raw(); |
| const exec_node *node_b = list_b->get_head_raw(); |
| |
| for (/* empty */ |
| ; !node_a->is_tail_sentinel() && !node_b->is_tail_sentinel() |
| ; node_a = node_a->next, node_b = node_b->next) { |
| ir_variable *a = (ir_variable *) node_a; |
| ir_variable *b = (ir_variable *) node_b; |
| |
| /* If the types of the parameters do not match, the parameters lists |
| * are different. |
| */ |
| if (a->type != b->type) |
| return false; |
| } |
| |
| /* Unless both lists are exhausted, they differ in length and, by |
| * definition, do not match. |
| */ |
| return (node_a->is_tail_sentinel() == node_b->is_tail_sentinel()); |
| } |
| |
| ir_function_signature * |
| ir_function::exact_matching_signature(_mesa_glsl_parse_state *state, |
| const exec_list *actual_parameters) |
| { |
| foreach_in_list(ir_function_signature, sig, &this->signatures) { |
| /* Skip over any built-ins that aren't available in this shader. */ |
| if (sig->is_builtin() && !sig->is_builtin_available(state)) |
| continue; |
| |
| if (parameter_lists_match_exact(&sig->parameters, actual_parameters)) |
| return sig; |
| } |
| return NULL; |
| } |
