chromium/third_party/spirv-tools/src/source/opt/local_redundancy_elimination.h

// Copyright (c) 2017 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef SOURCE_OPT_LOCAL_REDUNDANCY_ELIMINATION_H_
#define SOURCE_OPT_LOCAL_REDUNDANCY_ELIMINATION_H_

#include <map>

#include "source/opt/ir_context.h"
#include "source/opt/pass.h"
#include "source/opt/value_number_table.h"

namespace spvtools {
namespace opt {

// This pass implements local redundancy elimination. Its goal is to reduce the
// number of times the same value is computed. It works on each basic block
// independently, ie local. For each instruction in a basic block, it gets the
// value number for the result id, |id|, of the instruction. If that value
// number has already been computed in the basic block, it tries to replace the
// uses of |id| by the id that already contains the same value. Then the
// current instruction is deleted.
class LocalRedundancyEliminationPass : public Pass { … };

}  // namespace opt
}  // namespace spvtools

#endif  // SOURCE_OPT_LOCAL_REDUNDANCY_ELIMINATION_H_