Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//===- InstCombine.h - InstCombine pass -------------------------*- 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

///

/// This file provides the primary interface to the instcombine pass. This pass

/// is suitable for use in the new pass manager. For a pass that works with the

/// legacy pass manager, use \c createInstructionCombiningPass().

///

//===----------------------------------------------------------------------===//

#ifndef LLVM_TRANSFORMS_INSTCOMBINE_INSTCOMBINE_H

#define LLVM_TRANSFORMS_INSTCOMBINE_INSTCOMBINE_H

#include "llvm/IR/Function.h"

#include "llvm/IR/PassManager.h"

#include "llvm/Pass.h"

#define DEBUG_TYPE "instcombine"

#include "llvm/Transforms/Utils/InstructionWorklist.h"

namespace llvm {

class InstCombinePass : public PassInfoMixin<InstCombinePass> {

  InstructionWorklist Worklist;

  const unsigned MaxIterations;

public:

  explicit InstCombinePass();

  explicit InstCombinePass(unsigned MaxIterations);

  PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);

};

/// The legacy pass manager's instcombine pass.

///

/// This is a basic whole-function wrapper around the instcombine utility. It

/// will try to combine all instructions in the function.

class InstructionCombiningPass : public FunctionPass {

  InstructionWorklist Worklist;

  const unsigned MaxIterations;

public:

  static char ID; // Pass identification, replacement for typeid

  explicit InstructionCombiningPass();

  explicit InstructionCombiningPass(unsigned MaxIterations);

  void getAnalysisUsage(AnalysisUsage &AU) const override;

  bool runOnFunction(Function &F) override;

};

//===----------------------------------------------------------------------===//

//

// InstructionCombining - Combine instructions to form fewer, simple

// instructions. This pass does not modify the CFG, and has a tendency to make

// instructions dead, so a subsequent DCE pass is useful.

//

// This pass combines things like:

//    %Y = add int 1, %X

//    %Z = add int 1, %Y

// into:

//    %Z = add int 2, %X

//

FunctionPass *createInstructionCombiningPass();

FunctionPass *createInstructionCombiningPass(unsigned MaxIterations);

}

#undef DEBUG_TYPE

#endif