path: root/lib/Target/ARM/ARMFrameLowering.cpp

//=======- ARMFrameLowering.cpp - ARM Frame Information --------*- C++ -*-====//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the ARM implementation of TargetFrameLowering class.
//
//===----------------------------------------------------------------------===//

#include "ARMFrameLowering.h"
#include "ARMBaseInstrInfo.h"
#include "ARMBaseRegisterInfo.h"
#include "ARMMachineFunctionInfo.h"
#include "MCTargetDesc/ARMAddressingModes.h"
#include "llvm/Function.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Support/CommandLine.h"

using namespace llvm;

cl::opt<bool>
SpillAlignedNEONRegs("align-neon-spills", cl::Hidden,
                     cl::desc("Align ARM NEON spills in prolog and epilog"));

static MachineBasicBlock::iterator
skipAlignedDPRCS2Spills(MachineBasicBlock::iterator MI,
                        unsigned NumAlignedDPRCS2Regs);

/// hasFP - Return true if the specified function should have a dedicated frame
/// pointer register.  This is true if the function has variable sized allocas
/// or if frame pointer elimination is disabled.
bool ARMFrameLowering::hasFP(const MachineFunction &MF) const {
  const TargetRegisterInfo *RegInfo = MF.getTarget().getRegisterInfo();

  // iOS requires FP not to be clobbered for backtracing purpose.
  if (STI.isTargetIOS())
    return true;

  const MachineFrameInfo *MFI = MF.getFrameInfo();
  // Always eliminate non-leaf frame pointers.
  return ((