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//===-- IntrinsicLowering.h - Intrinsic Function Lowering -------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the IntrinsicLowering interface.  This interface allows
// addition of domain-specific or front-end specific intrinsics to LLVM without
// having to modify all of the C backend or interpreter.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CODEGEN_INTRINSICLOWERING_H
#define LLVM_CODEGEN_INTRINSICLOWERING_H

#include "llvm/IR/Intrinsics.h"

namespace llvm {
class CallInst;
class Module;
class DataLayout;

class IntrinsicLowering {
  const DataLayout &DL;

  bool Warned;

public:
  explicit IntrinsicLowering(const DataLayout &DL) : DL(DL), Warned(false) {}

  /// AddPrototypes - This method, if called, causes all of the prototypes
  /// that might be needed by an intrinsic lowering implementation to be
  /// inserted into the module specified.
  void AddPrototypes(Module &M);

  /// LowerIntrinsicCall - This method replaces a call with the LLVM function
  /// which should be used to implement the specified intrinsic function call.
  /// If an intrinsic function must be implemented by the code generator
  /// (such as va_start), this function should print a message and abort.
  ///
  /// Otherwise, if an intrinsic function call can be lowered, the code to
  /// implement it (often a call to a non-intrinsic function) is inserted
  /// _after_ the call instruction and the call is deleted.  The caller must
  /// be capable of handling this kind of change.
  ///
  void LowerIntrinsicCall(CallInst *CI);

  /// LowerToByteSwap - Replace a call instruction into a call to bswap
  /// intrinsic. Return false if it has determined the call is not a
  /// simple integer bswap.
  static bool LowerToByteSwap(CallInst *CI);
};
}

#endif