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#pragma once 
 
#ifdef __GNUC__ 
#pragma GCC diagnostic push 
#pragma GCC diagnostic ignored "-Wunused-parameter" 
#endif 
 
//=- MachineLoopUtils.h - Helper functions for manipulating loops -*- 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 
// 
//===----------------------------------------------------------------------===// 
 
#ifndef LLVM_LIB_CODEGEN_MACHINELOOPUTILS_H 
#define LLVM_LIB_CODEGEN_MACHINELOOPUTILS_H 
 
namespace llvm { 
class MachineLoop; 
class MachineBasicBlock; 
class MachineRegisterInfo; 
class TargetInstrInfo; 
 
enum LoopPeelDirection { 
  LPD_Front, ///< Peel the first iteration of the loop. 
  LPD_Back   ///< Peel the last iteration of the loop. 
}; 
 
/// Peels a single block loop. Loop must have two successors, one of which 
/// must be itself. Similarly it must have two predecessors, one of which must 
/// be itself. 
/// 
/// The loop block is copied and inserted into the CFG such that two copies of 
/// the loop follow on from each other. The copy is inserted either before or 
/// after the loop based on Direction. 
/// 
/// Phis are updated and an unconditional branch inserted at the end of the 
/// clone so as to execute a single iteration. 
/// 
/// The trip count of Loop is not updated. 
MachineBasicBlock *PeelSingleBlockLoop(LoopPeelDirection Direction, 
                                       MachineBasicBlock *Loop, 
                                       MachineRegisterInfo &MRI, 
                                       const TargetInstrInfo *TII); 
 
} // namespace llvm 
 
#endif // LLVM_LIB_CODEGEN_MACHINELOOPUTILS_H 
 
#ifdef __GNUC__ 
#pragma GCC diagnostic pop 
#endif