#include "Target/SystemZ/SystemZFrameLowering.h"

Inheritance diagram for llvm::SystemZFrameLowering:

Collaboration diagram for llvm::SystemZFrameLowering:

Public Member Functions
	SystemZFrameLowering ()

bool	isFPCloseToIncomingSP () const override
	isFPCloseToIncomingSP - Return true if the frame pointer is close to the incoming stack pointer, false if it is close to the post-prologue stack pointer. More...

const SpillSlot *	getCalleeSavedSpillSlots (unsigned &NumEntries) const override
	getCalleeSavedSpillSlots - This method returns a pointer to an array of pairs, that contains an entry for each callee saved register that must be spilled to a particular stack location if it is spilled. More...

void	determineCalleeSaves (MachineFunction &MF, BitVector &SavedRegs, RegScavenger *RS) const override
	This method determines which of the registers reported by TargetRegisterInfo::getCalleeSavedRegs() should actually get saved. More...

bool	spillCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, const std::vector< CalleeSavedInfo > &CSI, const TargetRegisterInfo *TRI) const override
	spillCalleeSavedRegisters - Issues instruction(s) to spill all callee saved registers and returns true if it isn't possible / profitable to do so by issuing a series of store instructions via storeRegToStackSlot(). More...

bool	restoreCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBII, std::vector< CalleeSavedInfo > &CSI, const TargetRegisterInfo *TRI) const override
	restoreCalleeSavedRegisters - Issues instruction(s) to restore all callee saved registers and returns true if it isn't possible / profitable to do so by issuing a series of load instructions via loadRegToStackSlot(). More...

void	processFunctionBeforeFrameFinalized (MachineFunction &MF, RegScavenger *RS) const override
	processFunctionBeforeFrameFinalized - This method is called immediately before the specified function's frame layout (MF.getFrameInfo()) is finalized. More...

void	emitPrologue (MachineFunction &MF, MachineBasicBlock &MBB) const override
	emitProlog/emitEpilog - These methods insert prolog and epilog code into the function. More...

void	emitEpilogue (MachineFunction &MF, MachineBasicBlock &MBB) const override

bool	hasFP (const MachineFunction &MF) const override
	hasFP - Return true if the specified function should have a dedicated frame pointer register. More...

bool	hasReservedCallFrame (const MachineFunction &MF) const override
	hasReservedCallFrame - Under normal circumstances, when a frame pointer is not required, we reserve argument space for call sites in the function immediately on entry to the current function. More...

MachineBasicBlock::iterator	eliminateCallFramePseudoInstr (MachineFunction &MF, MachineBasicBlock &MBB, MachineBasicBlock::iterator MI) const override
	This method is called during prolog/epilog code insertion to eliminate call frame setup and destroy pseudo instructions (but only if the Target is using them). More...

unsigned	getRegSpillOffset (unsigned Reg) const

Public Member Functions inherited from llvm::TargetFrameLowering
	TargetFrameLowering (StackDirection D, unsigned StackAl, int LAO, unsigned TransAl=1, bool StackReal=true)

virtual	~TargetFrameLowering ()

StackDirection	getStackGrowthDirection () const
	getStackGrowthDirection - Return the direction the stack grows More...

unsigned	getStackAlignment () const
	getStackAlignment - This method returns the number of bytes to which the stack pointer must be aligned on entry to a function. More...

int	alignSPAdjust (int SPAdj) const
	alignSPAdjust - This method aligns the stack adjustment to the correct alignment. More...

unsigned	getTransientStackAlignment () const
	getTransientStackAlignment - This method returns the number of bytes to which the stack pointer must be aligned at all times, even between calls. More...

bool	isStackRealignable () const
	isStackRealignable - This method returns whether the stack can be realigned. More...

virtual unsigned	getStackAlignmentSkew (const MachineFunction &MF) const
	Return the skew that has to be applied to stack alignment under certain conditions (e.g. More...

int	getOffsetOfLocalArea () const
	getOffsetOfLocalArea - This method returns the offset of the local area from the stack pointer on entrance to a function. More...

virtual bool	assignCalleeSavedSpillSlots (MachineFunction &MF, const TargetRegisterInfo *TRI, std::vector< CalleeSavedInfo > &CSI) const
	assignCalleeSavedSpillSlots - Allows target to override spill slot assignment logic. More...

virtual bool	targetHandlesStackFrameRounding () const
	targetHandlesStackFrameRounding - Returns true if the target is responsible for rounding up the stack frame (probably at emitPrologue time). More...

virtual bool	enableShrinkWrapping (const MachineFunction &MF) const
	Returns true if the target will correctly handle shrink wrapping. More...

virtual bool	enableStackSlotScavenging (const MachineFunction &MF) const
	Returns true if the stack slot holes in the fixed and callee-save stack area should be used when allocating other stack locations to reduce stack size. More...

virtual bool	enableCalleeSaveSkip (const MachineFunction &MF) const
	Returns true if the target can safely skip saving callee-saved registers for noreturn nounwind functions. More...

virtual void	inlineStackProbe (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const
	Replace a StackProbe stub (if any) with the actual probe code inline. More...

virtual void	adjustForSegmentedStacks (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const
	Adjust the prologue to have the function use segmented stacks. More...

virtual void	adjustForHiPEPrologue (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const
	Adjust the prologue to add Erlang Run-Time System (ERTS) specific code in the assembly prologue to explicitly handle the stack. More...

virtual bool	keepFramePointer (const MachineFunction &MF) const
	Return true if the target wants to keep the frame pointer regardless of the function attribute "frame-pointer". More...

virtual bool	canSimplifyCallFramePseudos (const MachineFunction &MF) const
	canSimplifyCallFramePseudos - When possible, it's best to simplify the call frame pseudo ops before doing frame index elimination. More...

virtual bool	needsFrameIndexResolution (const MachineFunction &MF) const

virtual int	getFrameIndexReference (const MachineFunction &MF, int FI, unsigned &FrameReg) const
	getFrameIndexReference - This method should return the base register and offset used to reference a frame index location. More...

virtual int	getFrameIndexReferencePreferSP (const MachineFunction &MF, int FI, unsigned &FrameReg, bool IgnoreSPUpdates) const
	Same as `getFrameIndexReference`, except that the stack pointer (as opposed to the frame pointer) will be the preferred value for `FrameReg`. More...

virtual unsigned	getWinEHParentFrameOffset (const MachineFunction &MF) const

virtual void	orderFrameObjects (const MachineFunction &MF, SmallVectorImpl< int > &objectsToAllocate) const
	Order the symbols in the local stack frame. More...

virtual bool	canUseAsPrologue (const MachineBasicBlock &MBB) const
	Check whether or not the given `MBB` can be used as a prologue for the target. More...

virtual bool	canUseAsEpilogue (const MachineBasicBlock &MBB) const
	Check whether or not the given `MBB` can be used as a epilogue for the target. More...

virtual int	getInitialCFAOffset (const MachineFunction &MF) const
	Return initial CFA offset value i.e. More...

virtual unsigned	getInitialCFARegister (const MachineFunction &MF) const
	Return initial CFA register value i.e. More...

Additional Inherited Members
Public Types inherited from llvm::TargetFrameLowering
enum	StackDirection { StackGrowsUp, StackGrowsDown }

Static Public Member Functions inherited from llvm::TargetFrameLowering
static bool	isSafeForNoCSROpt (const Function &F)
	Check if given function is safe for not having callee saved registers. More...

Detailed Description

Definition at line 20 of file SystemZFrameLowering.h.

Constructor & Destructor Documentation

◆ SystemZFrameLowering()

SystemZFrameLowering::SystemZFrameLowering ( )

Definition at line 49 of file SystemZFrameLowering.cpp.

References llvm::array_lengthof(), E, llvm::IndexedMap< T, ToIndexT >::grow(), I, and Reg.

Member Function Documentation

◆ determineCalleeSaves()

void SystemZFrameLowering::determineCalleeSaves	(	MachineFunction &	MF,
		BitVector &	SavedRegs,
		RegScavenger *	RS
	)		const

overridevirtual

This method determines which of the registers reported by TargetRegisterInfo::getCalleeSavedRegs() should actually get saved.

The default implementation checks populates the SavedRegs bitset with all registers which are modified in the function, targets may override this function to save additional registers. This method also sets up the register scavenger ensuring there is a free register or a frameindex available.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 65 of file SystemZFrameLowering.cpp.

References llvm::SystemZ::ArgGPRs, contains(), llvm::TargetFrameLowering::determineCalleeSaves(), llvm::TargetRegisterInfo::getCalleeSavedRegs(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::MachineFunction::getLandingPads(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), llvm::SystemZMachineFunctionInfo::getVarArgsFirstGPR(), llvm::MachineFrameInfo::hasCalls(), hasFP(), I, llvm::Function::isVarArg(), llvm::SystemZ::NumArgGPRs, Reg, llvm::BitVector::set(), llvm::BitVector::test(), and TRI.

Referenced by isFPCloseToIncomingSP().

◆ eliminateCallFramePseudoInstr()

MachineBasicBlock::iterator SystemZFrameLowering::eliminateCallFramePseudoInstr	(	MachineFunction &	MF,
		MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MI
	)		const

overridevirtual

This method is called during prolog/epilog code insertion to eliminate call frame setup and destroy pseudo instructions (but only if the Target is using them).

It is responsible for eliminating these instructions, replacing them with concrete instructions. This method need only be implemented if using call frame setup/destroy pseudo instructions. Returns an iterator pointing to the instruction after the replaced one.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 532 of file SystemZFrameLowering.cpp.

References assert(), llvm::MachineBasicBlock::erase(), hasReservedCallFrame(), and llvm_unreachable.

Referenced by hasReservedCallFrame(), and isFPCloseToIncomingSP().

◆ emitEpilogue()

void SystemZFrameLowering::emitEpilogue	(	MachineFunction &	MF,
		MachineBasicBlock &	MBB
	)		const

overridevirtual

Implements llvm::TargetFrameLowering.

Definition at line 474 of file SystemZFrameLowering.cpp.

References assert(), emitIncrement(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::MachineBasicBlock::getLastNonDebugInstr(), llvm::SystemZMachineFunctionInfo::getLowSavedGPR(), llvm::MachineFunction::getSubtarget(), and llvm_unreachable.

Referenced by isFPCloseToIncomingSP().

◆ emitPrologue()

void SystemZFrameLowering::emitPrologue	(	MachineFunction &	MF,
		MachineBasicBlock &	MBB
	)		const

overridevirtual

emitProlog/emitEpilog - These methods insert prolog and epilog code into the function.

Implements llvm::TargetFrameLowering.

Definition at line 342 of file SystemZFrameLowering.cpp.

Referenced by isFPCloseToIncomingSP().

◆ getCalleeSavedSpillSlots()

const TargetFrameLowering::SpillSlot * SystemZFrameLowering::getCalleeSavedSpillSlots ( unsigned & NumEntries ) const

overridevirtual

getCalleeSavedSpillSlots - This method returns a pointer to an array of pairs, that contains an entry for each callee saved register that must be spilled to a particular stack location if it is spilled.

Each entry in this array contains a <register,offset> pair, indicating the fixed offset from the incoming stack pointer that each register should be spilled at. If a register is not listed here, the code generator is allowed to spill it anywhere it chooses.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 60 of file SystemZFrameLowering.cpp.

References llvm::array_lengthof().

Referenced by isFPCloseToIncomingSP().

◆ getRegSpillOffset()

unsigned llvm::SystemZFrameLowering::getRegSpillOffset ( unsigned Reg ) const

inline

Definition at line 53 of file SystemZFrameLowering.h.

References Reg.

◆ hasFP()

bool SystemZFrameLowering::hasFP ( const MachineFunction & MF ) const

overridevirtual

hasFP - Return true if the specified function should have a dedicated frame pointer register.

For most targets this is true only if the function has variable sized allocas or if frame pointer elimination is disabled.

Implements llvm::TargetFrameLowering.

Definition at line 516 of file SystemZFrameLowering.cpp.

References llvm::TargetOptions::DisableFramePointerElim(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::MachineFunction::getTarget(), llvm::MachineFrameInfo::hasVarSizedObjects(), and llvm::TargetMachine::Options.

Referenced by determineCalleeSaves(), emitPrologue(), llvm::SystemZRegisterInfo::getFrameRegister(), llvm::SystemZRegisterInfo::getReservedRegs(), isFPCloseToIncomingSP(), and restoreCalleeSavedRegisters().

◆ hasReservedCallFrame()

bool SystemZFrameLowering::hasReservedCallFrame ( const MachineFunction & MF ) const

overridevirtual

hasReservedCallFrame - Under normal circumstances, when a frame pointer is not required, we reserve argument space for call sites in the function immediately on entry to the current function.

This eliminates the need for add/sub sp brackets around call sites. Returns true if the call frame is included as part of the stack frame.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 523 of file SystemZFrameLowering.cpp.

References eliminateCallFramePseudoInstr().

Referenced by eliminateCallFramePseudoInstr(), and isFPCloseToIncomingSP().

◆ isFPCloseToIncomingSP()

bool llvm::SystemZFrameLowering::isFPCloseToIncomingSP ( ) const

inlineoverridevirtual

isFPCloseToIncomingSP - Return true if the frame pointer is close to the incoming stack pointer, false if it is close to the post-prologue stack pointer.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 27 of file SystemZFrameLowering.h.

References determineCalleeSaves(), eliminateCallFramePseudoInstr(), emitEpilogue(), emitPrologue(), getCalleeSavedSpillSlots(), hasFP(), hasReservedCallFrame(), MI, processFunctionBeforeFrameFinalized(), restoreCalleeSavedRegisters(), spillCalleeSavedRegisters(), and TRI.

◆ processFunctionBeforeFrameFinalized()

void SystemZFrameLowering::processFunctionBeforeFrameFinalized	(	MachineFunction &	MF,
		RegScavenger *	RS
	)		const

overridevirtual

processFunctionBeforeFrameFinalized - This method is called immediately before the specified function's frame layout (MF.getFrameInfo()) is finalized.

Once the frame is finalized, MO_FrameIndex operands are replaced with direct constants. This method is optional.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 285 of file SystemZFrameLowering.cpp.

References llvm::RegScavenger::addScavengingFrameIndex(), llvm::SystemZMC::CallFrameSize, llvm::MachineFrameInfo::CreateStackObject(), llvm::MachineFrameInfo::estimateStackSize(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFrameInfo::getObjectIndexBegin(), llvm::MachineFrameInfo::getObjectOffset(), llvm::MachineFrameInfo::getObjectSize(), I, and llvm::max().

Referenced by isFPCloseToIncomingSP(), and restoreCalleeSavedRegisters().

◆ restoreCalleeSavedRegisters()

bool SystemZFrameLowering::restoreCalleeSavedRegisters	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MI,
		std::vector< CalleeSavedInfo > &	CSI,
		const TargetRegisterInfo *	TRI
	)		const

overridevirtual

restoreCalleeSavedRegisters - Issues instruction(s) to restore all callee saved registers and returns true if it isn't possible / profitable to do so by issuing a series of load instructions via loadRegToStackSlot().

If it returns true, and any of the registers in CSI is not restored, it sets the corresponding Restored flag in CSI to false. Returns false otherwise.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 226 of file SystemZFrameLowering.cpp.

References llvm::MachineInstrBuilder::addImm(), llvm::MachineInstrBuilder::addReg(), assert(), llvm::BuildMI(), contains(), llvm::RegState::Define, E, llvm::MachineBasicBlock::end(), llvm::MCInstrInfo::get(), llvm::SystemZMachineFunctionInfo::getHighSavedGPR(), llvm::MachineFunction::getInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::SystemZMachineFunctionInfo::getLowSavedGPR(), llvm::MachineBasicBlock::getParent(), llvm::MachineFunction::getSubtarget(), hasFP(), I, llvm::RegState::ImplicitDefine, llvm::TargetInstrInfo::loadRegFromStackSlot(), processFunctionBeforeFrameFinalized(), Reg, and TII.

Referenced by isFPCloseToIncomingSP(), and spillCalleeSavedRegisters().

◆ spillCalleeSavedRegisters()

bool SystemZFrameLowering::spillCalleeSavedRegisters	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MI,
		const std::vector< CalleeSavedInfo > &	CSI,
		const TargetRegisterInfo *	TRI
	)		const

overridevirtual

spillCalleeSavedRegisters - Issues instruction(s) to spill all callee saved registers and returns true if it isn't possible / profitable to do so by issuing a series of store instructions via storeRegToStackSlot().

Returns false otherwise.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 132 of file SystemZFrameLowering.cpp.

References llvm::MachineInstrBuilder::addImm(), llvm::MachineBasicBlock::addLiveIn(), llvm::MachineInstrBuilder::addReg(), addSavedGPR(), llvm::SystemZ::ArgGPRs, assert(), llvm::BuildMI(), contains(), E, llvm::MCInstrInfo::get(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::MachineBasicBlock::getParent(), llvm::MachineFunction::getSubtarget(), llvm::SystemZMachineFunctionInfo::getVarArgsFirstGPR(), I, llvm::Function::isVarArg(), llvm::SystemZ::NumArgGPRs, Reg, restoreCalleeSavedRegisters(), llvm::SystemZMachineFunctionInfo::setHighSavedGPR(), llvm::SystemZMachineFunctionInfo::setLowSavedGPR(), llvm::TargetInstrInfo::storeRegToStackSlot(), and TII.