150 lines
6.4 KiB
C++
150 lines
6.4 KiB
C++
//===-- PPCFrameLowering.h - Define frame lowering for PowerPC --*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_LIB_TARGET_POWERPC_PPCFRAMELOWERING_H
|
|
#define LLVM_LIB_TARGET_POWERPC_PPCFRAMELOWERING_H
|
|
|
|
#include "PPC.h"
|
|
#include "llvm/ADT/STLExtras.h"
|
|
#include "llvm/Target/TargetFrameLowering.h"
|
|
#include "llvm/Target/TargetMachine.h"
|
|
|
|
namespace llvm {
|
|
class PPCSubtarget;
|
|
|
|
class PPCFrameLowering: public TargetFrameLowering {
|
|
const PPCSubtarget &Subtarget;
|
|
const unsigned ReturnSaveOffset;
|
|
const unsigned TOCSaveOffset;
|
|
const unsigned FramePointerSaveOffset;
|
|
const unsigned LinkageSize;
|
|
const unsigned BasePointerSaveOffset;
|
|
|
|
/**
|
|
* \brief Find register[s] that can be used in function prologue and epilogue
|
|
*
|
|
* Find register[s] that can be use as scratch register[s] in function
|
|
* prologue and epilogue to save various registers (Link Register, Base
|
|
* Pointer, etc.). Prefer R0/R12, if available. Otherwise choose whatever
|
|
* register[s] are available.
|
|
*
|
|
* This method will return true if it is able to find enough unique scratch
|
|
* registers (1 or 2 depending on the requirement). If it is unable to find
|
|
* enough available registers in the block, it will return false and set
|
|
* any passed output parameter that corresponds to a required unique register
|
|
* to PPC::NoRegister.
|
|
*
|
|
* \param[in] MBB The machine basic block to find an available register for
|
|
* \param[in] UseAtEnd Specify whether the scratch register will be used at
|
|
* the end of the basic block (i.e., will the scratch
|
|
* register kill a register defined in the basic block)
|
|
* \param[in] TwoUniqueRegsRequired Specify whether this basic block will
|
|
* require two unique scratch registers.
|
|
* \param[out] SR1 The scratch register to use
|
|
* \param[out] SR2 The second scratch register. If this pointer is not null
|
|
* the function will attempt to set it to an available
|
|
* register regardless of whether there is a hard requirement
|
|
* for two unique scratch registers.
|
|
* \return true if the required number of registers was found.
|
|
* false if the required number of scratch register weren't available.
|
|
* If either output parameter refers to a required scratch register
|
|
* that isn't available, it will be set to an invalid value.
|
|
*/
|
|
bool findScratchRegister(MachineBasicBlock *MBB,
|
|
bool UseAtEnd,
|
|
bool TwoUniqueRegsRequired = false,
|
|
unsigned *SR1 = nullptr,
|
|
unsigned *SR2 = nullptr) const;
|
|
bool twoUniqueScratchRegsRequired(MachineBasicBlock *MBB) const;
|
|
|
|
/**
|
|
* \brief Create branch instruction for PPC::TCRETURN* (tail call return)
|
|
*
|
|
* \param[in] MBB that is terminated by PPC::TCRETURN*
|
|
*/
|
|
void createTailCallBranchInstr(MachineBasicBlock &MBB) const;
|
|
|
|
public:
|
|
PPCFrameLowering(const PPCSubtarget &STI);
|
|
|
|
unsigned determineFrameLayout(MachineFunction &MF,
|
|
bool UpdateMF = true,
|
|
bool UseEstimate = false) const;
|
|
|
|
/// emitProlog/emitEpilog - These methods insert prolog and epilog code into
|
|
/// the function.
|
|
void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
|
|
void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
|
|
|
|
bool hasFP(const MachineFunction &MF) const override;
|
|
bool needsFP(const MachineFunction &MF) const;
|
|
void replaceFPWithRealFP(MachineFunction &MF) const;
|
|
|
|
void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs,
|
|
RegScavenger *RS = nullptr) const override;
|
|
void processFunctionBeforeFrameFinalized(MachineFunction &MF,
|
|
RegScavenger *RS = nullptr) const override;
|
|
void addScavengingSpillSlot(MachineFunction &MF, RegScavenger *RS) const;
|
|
|
|
bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
|
|
MachineBasicBlock::iterator MI,
|
|
const std::vector<CalleeSavedInfo> &CSI,
|
|
const TargetRegisterInfo *TRI) const override;
|
|
|
|
MachineBasicBlock::iterator
|
|
eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
|
|
MachineBasicBlock::iterator I) const override;
|
|
|
|
bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
|
|
MachineBasicBlock::iterator MI,
|
|
const std::vector<CalleeSavedInfo> &CSI,
|
|
const TargetRegisterInfo *TRI) const override;
|
|
|
|
/// targetHandlesStackFrameRounding - Returns true if the target is
|
|
/// responsible for rounding up the stack frame (probably at emitPrologue
|
|
/// time).
|
|
bool targetHandlesStackFrameRounding() const override { return true; }
|
|
|
|
/// getReturnSaveOffset - Return the previous frame offset to save the
|
|
/// return address.
|
|
unsigned getReturnSaveOffset() const { return ReturnSaveOffset; }
|
|
|
|
/// getTOCSaveOffset - Return the previous frame offset to save the
|
|
/// TOC register -- 64-bit SVR4 ABI only.
|
|
unsigned getTOCSaveOffset() const { return TOCSaveOffset; }
|
|
|
|
/// getFramePointerSaveOffset - Return the previous frame offset to save the
|
|
/// frame pointer.
|
|
unsigned getFramePointerSaveOffset() const { return FramePointerSaveOffset; }
|
|
|
|
/// getBasePointerSaveOffset - Return the previous frame offset to save the
|
|
/// base pointer.
|
|
unsigned getBasePointerSaveOffset() const { return BasePointerSaveOffset; }
|
|
|
|
/// getLinkageSize - Return the size of the PowerPC ABI linkage area.
|
|
///
|
|
unsigned getLinkageSize() const { return LinkageSize; }
|
|
|
|
const SpillSlot *
|
|
getCalleeSavedSpillSlots(unsigned &NumEntries) const override;
|
|
|
|
bool enableShrinkWrapping(const MachineFunction &MF) const override;
|
|
|
|
/// Methods used by shrink wrapping to determine if MBB can be used for the
|
|
/// function prologue/epilogue.
|
|
bool canUseAsPrologue(const MachineBasicBlock &MBB) const override;
|
|
bool canUseAsEpilogue(const MachineBasicBlock &MBB) const override;
|
|
};
|
|
} // End llvm namespace
|
|
|
|
#endif
|