/*
* 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.
*/
/**
* \file lower_noise.cpp
* IR lower pass to remove noise opcodes.
*
* \author Ian Romanick <ian.d.romanick@intel.com>
*/
#include "ir.h"
#include "ir_rvalue_visitor.h"
class lower_noise_visitor : public ir_rvalue_visitor {
public:
lower_noise_visitor() : progress(false)
{
/* empty */
}
void handle_rvalue(ir_rvalue **rvalue)
{
if (!*rvalue)
return;
ir_expression *expr = (*rvalue)->as_expression();
if (!expr)
return;
/* In the future, ir_unop_noise may be replaced by a call to a function
* that implements noise. No hardware has a noise instruction.
*/
if (expr->operation == ir_unop_noise) {
*rvalue = ir_constant::zero(ralloc_parent(expr), expr->type);
this->progress = true;
}
}
bool progress;
};
bool
lower_noise(exec_list *instructions)
{
lower_noise_visitor v;
visit_list_elements(&v, instructions);
return v.progress;
}