/*
* 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 "glsl_types.h"
#include "ir.h"
int
type_compare(const glsl_type *a, const glsl_type *b)
{
/* If the types are the same, they trivially match.
*/
if (a == b)
return 0;
switch (a->base_type) {
case GLSL_TYPE_UINT:
case GLSL_TYPE_INT:
case GLSL_TYPE_BOOL:
/* There is no implicit conversion to or from integer types or bool.
*/
if ((a->is_integer() != b->is_integer())
|| (a->is_boolean() != b->is_boolean()))
return -1;
/* FALLTHROUGH */
case GLSL_TYPE_FLOAT:
if ((a->vector_elements != b->vector_elements)
|| (a->matrix_columns != b->matrix_columns))
return -1;
return 1;
case GLSL_TYPE_SAMPLER:
case GLSL_TYPE_STRUCT:
/* Samplers and structures must match exactly.
*/
return -1;
case GLSL_TYPE_ARRAY:
if ((b->base_type != GLSL_TYPE_ARRAY)
|| (a->length != b->length))
return -1;
/* From GLSL 1.50 spec, page 27 (page 33 of the PDF):
* "There are no implicit array or structure conversions."
*
* If the comparison of the array element types detects that a conversion
* would be required, the array types do not match.
*/
return (type_compare(a->fields.array, b->fields.array) == 0) ? 0 : -1;
case GLSL_TYPE_VOID:
case GLSL_TYPE_ERROR:
default:
/* These are all error conditions. It is invalid for a parameter to
* a function to be declared as error, void, or a function.
*/
return -1;
}
/* This point should be unreachable.
*/
assert(0);
}
static int
parameter_lists_match(const exec_list *list_a, const exec_list *list_b)
{
const exec_node *node_a = list_a->head;
const exec_node *node_b = list_b->head;
int total_score = 0;
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 -1;
const ir_variable *const param = (ir_variable *) node_a;
const ir_instruction *const actual = (ir_instruction *) node_b;
/* Determine whether or not the types match. If the types are an
* exact match, the match score is zero. If the types don't match
* but the actual parameter can be coerced to the type of the declared
* parameter, the match score is one.
*/
int score;
switch ((enum ir_variable_mode)(param->mode)) {
case ir_var_auto:
case ir_var_uniform:
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 -1;
case ir_var_in:
score = type_compare(param->type, actual->type);
break;
case ir_var_out:
score = type_compare(actual->type, param->type);
break;
case ir_var_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.
*/
score = (type_compare(actual->type, param->type) == 0) ? 0 : -1;
break;
default:
assert(false);
}
if (score < 0)
return -1;
total_score += score;
}
/* 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 -1;
return total_score;
}
ir_function_signature *
ir_function::matching_signature(const exec_list *actual_parameters)
{
ir_function_signature *match = NULL;
foreach_iter(exec_list_iterator, iter, signatures) {
ir_function_signature *const sig =
(ir_function_signature *) iter.get();
const int score = parameter_lists_match(& sig->parameters,
actual_parameters);
if (score == 0)
return sig;
if (score > 0) {
if (match != NULL)
return NULL;
match = sig;
}
}
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->head;
const exec_node *node_b = list_b->head;
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(const exec_list *actual_parameters)
{
foreach_iter(exec_list_iterator, iter, signatures) {
ir_function_signature *const sig =
(ir_function_signature *) iter.get();
if (parameter_lists_match_exact(&sig->parameters, actual_parameters))
return sig;
}
return NULL;
}