5ef4296cb6
Doing so allow you to easily tell what the pass did using the existing infrastructure in the OPT macro. Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com> Reviewed-by: Kenneth Graunke <kenneth@whitecape.org> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10292>
130 lines
3.7 KiB
C++
130 lines
3.7 KiB
C++
/*
|
|
* Copyright © 2016 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.
|
|
*/
|
|
|
|
/**
|
|
* \file propagate_invariance.cpp
|
|
* Propagate the "invariant" and "precise" qualifiers to variables used to
|
|
* compute invariant or precise values.
|
|
*
|
|
* The GLSL spec (depending on what version you read) says, among the
|
|
* conditions for getting bit-for-bit the same values on an invariant output:
|
|
*
|
|
* "All operations in the consuming expressions and any intermediate
|
|
* expressions must be the same, with the same order of operands and same
|
|
* associativity, to give the same order of evaluation."
|
|
*
|
|
* This effectively means that if a variable is used to compute an invariant
|
|
* value then that variable becomes invariant. The same should apply to the
|
|
* "precise" qualifier.
|
|
*/
|
|
|
|
#include "ir.h"
|
|
#include "ir_visitor.h"
|
|
#include "ir_rvalue_visitor.h"
|
|
#include "ir_optimization.h"
|
|
#include "compiler/glsl_types.h"
|
|
|
|
namespace {
|
|
|
|
class ir_invariance_propagation_visitor : public ir_hierarchical_visitor {
|
|
public:
|
|
ir_invariance_propagation_visitor()
|
|
{
|
|
this->progress = false;
|
|
this->dst_var = NULL;
|
|
}
|
|
|
|
virtual ~ir_invariance_propagation_visitor()
|
|
{
|
|
/* empty */
|
|
}
|
|
|
|
virtual ir_visitor_status visit_enter(ir_assignment *ir);
|
|
virtual ir_visitor_status visit_leave(ir_assignment *ir);
|
|
virtual ir_visitor_status visit(ir_dereference_variable *ir);
|
|
|
|
ir_variable *dst_var;
|
|
bool progress;
|
|
};
|
|
|
|
} /* unnamed namespace */
|
|
|
|
ir_visitor_status
|
|
ir_invariance_propagation_visitor::visit_enter(ir_assignment *ir)
|
|
{
|
|
assert(this->dst_var == NULL);
|
|
ir_variable *var = ir->lhs->variable_referenced();
|
|
if (var->data.invariant || var->data.precise) {
|
|
this->dst_var = var;
|
|
return visit_continue;
|
|
} else {
|
|
return visit_continue_with_parent;
|
|
}
|
|
}
|
|
|
|
ir_visitor_status
|
|
ir_invariance_propagation_visitor::visit_leave(ir_assignment *)
|
|
{
|
|
this->dst_var = NULL;
|
|
|
|
return visit_continue;
|
|
}
|
|
|
|
ir_visitor_status
|
|
ir_invariance_propagation_visitor::visit(ir_dereference_variable *ir)
|
|
{
|
|
if (this->dst_var == NULL)
|
|
return visit_continue;
|
|
|
|
if (this->dst_var->data.invariant) {
|
|
if (!ir->var->data.invariant)
|
|
this->progress = true;
|
|
|
|
ir->var->data.invariant = true;
|
|
}
|
|
|
|
if (this->dst_var->data.precise) {
|
|
if (!ir->var->data.precise)
|
|
this->progress = true;
|
|
|
|
ir->var->data.precise = true;
|
|
}
|
|
|
|
return visit_continue;
|
|
}
|
|
|
|
bool
|
|
propagate_invariance(exec_list *instructions)
|
|
{
|
|
ir_invariance_propagation_visitor visitor;
|
|
bool progress = false;
|
|
|
|
do {
|
|
visitor.progress = false;
|
|
visit_list_elements(&visitor, instructions);
|
|
progress = progress || visitor.progress;
|
|
} while (visitor.progress);
|
|
|
|
return progress;
|
|
}
|