InstSimplifyPass.h

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//===- InstSimplifyPass.h ---------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
/// \file
///
/// Defines passes for running instruction simplification across chunks of IR.
///
//===----------------------------------------------------------------------===//
 
#ifndef LLVM_TRANSFORMS_SCALAR_INSTSIMPLIFYPASS_H
#define LLVM_TRANSFORMS_SCALAR_INSTSIMPLIFYPASS_H
 
#include "llvm/IR/PassManager.h"
 
namespace llvm {
 
class FunctionPass;
 
/// Run instruction simplification across each instruction in the function.
///
/// Instruction simplification has useful constraints in some contexts:
/// - It will never introduce *new* instructions.
/// - There is no need to iterate to a fixed point.
///
/// Many passes use instruction simplification as a library facility, but it may
/// also be useful (in tests and other contexts) to have access to this very
/// restricted transform at a pass granularity. However, for a much more
/// powerful and comprehensive peephole optimization engine, see the
/// `instcombine` pass instead.
class InstSimplifyPass : public PassInfoMixin<InstSimplifyPass> {
public:
  PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
};
 
} // end namespace llvm
 
#endif // LLVM_TRANSFORMS_SCALAR_INSTSIMPLIFYPASS_H