#include "Target/AArch64/AArch64FrameLowering.h"

Inheritance diagram for llvm::AArch64FrameLowering:

Public Member Functions
	AArch64FrameLowering ()

void	resetCFIToInitialState (MachineBasicBlock &MBB) const override
	Emit CFI instructions that recreate the state of the unwind information upon fucntion entry.

MachineBasicBlock::iterator	eliminateCallFramePseudoInstr (MachineFunction &MF, MachineBasicBlock &MBB, MachineBasicBlock::iterator I) 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).

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

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

bool	enableCFIFixup (MachineFunction &MF) const override
	Returns true if we may need to fix the unwind information for the function.

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

StackOffset	getFrameIndexReference (const MachineFunction &MF, int FI, Register &FrameReg) const override
	getFrameIndexReference - Provide a base+offset reference to an FI slot for debug info.

StackOffset	getFrameIndexReferenceFromSP (const MachineFunction &MF, int FI) const override
	getFrameIndexReferenceFromSP - This method returns the offset from the stack pointer to the slot of the specified index.

StackOffset	resolveFrameIndexReference (const MachineFunction &MF, int FI, Register &FrameReg, bool PreferFP, bool ForSimm) const

StackOffset	resolveFrameOffsetReference (const MachineFunction &MF, int64_t ObjectOffset, bool isFixed, bool isSVE, Register &FrameReg, bool PreferFP, bool ForSimm) const

bool	spillCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, ArrayRef< 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().

bool	restoreCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, MutableArrayRef< 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().

bool	canUseRedZone (const MachineFunction &MF) const
	Can this function use the red zone for local allocations.

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

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.

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

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.

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

bool	enableStackSlotScavenging (const MachineFunction &MF) const override
	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.

TargetStackID::Value	getStackIDForScalableVectors () const override
	Returns the StackID that scalable vectors should be associated with.

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.

void	processFunctionBeforeFrameIndicesReplaced (MachineFunction &MF, RegScavenger *RS) const override
	processFunctionBeforeFrameIndicesReplaced - This method is called immediately before MO_FrameIndex operands are eliminated, but after the frame is finalized.

unsigned	getWinEHParentFrameOffset (const MachineFunction &MF) const override
	The parent frame offset (aka dispFrame) is only used on X86_64 to retrieve the parent's frame pointer.

unsigned	getWinEHFuncletFrameSize (const MachineFunction &MF) const
	Funclets only need to account for space for the callee saved registers, as the locals are accounted for in the parent's stack frame.

StackOffset	getFrameIndexReferencePreferSP (const MachineFunction &MF, int FI, Register &FrameReg, bool IgnoreSPUpdates) const override
	For Win64 AArch64 EH, the offset to the Unwind object is from the SP before the update.

StackOffset	getNonLocalFrameIndexReference (const MachineFunction &MF, int FI) const override
	getNonLocalFrameIndexReference - This method returns the offset used to reference a frame index location.

int	getSEHFrameIndexOffset (const MachineFunction &MF, int FI) const

bool	isSupportedStackID (TargetStackID::Value ID) const override

bool	isStackIdSafeForLocalArea (unsigned StackId) const override
	This method returns whether or not it is safe for an object with the given stack id to be bundled into the local area.

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

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

virtual	~TargetFrameLowering ()

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

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

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

virtual uint64_t	getStackThreshold () const
	getStackThreshold - Return the maximum stack size

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

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

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

virtual bool	isStackIdSafeForLocalArea (unsigned StackId) const
	This method returns whether or not it is safe for an object with the given stack id to be bundled into the local area.

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

virtual bool	allocateScavengingFrameIndexesNearIncomingSP (const MachineFunction &MF) const
	Control the placement of special register scavenging spill slots when allocating a stack frame.

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

virtual bool	assignCalleeSavedSpillSlots (MachineFunction &MF, const TargetRegisterInfo *TRI, std::vector< CalleeSavedInfo > &CSI) const

virtual const SpillSlot *	getCalleeSavedSpillSlots (unsigned &NumEntries) const
	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.

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

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

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.

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

virtual void	emitPrologue (MachineFunction &MF, MachineBasicBlock &MBB) const =0
	emitProlog/emitEpilog - These methods insert prolog and epilog code into the function.

virtual void	emitEpilogue (MachineFunction &MF, MachineBasicBlock &MBB) const =0

virtual void	emitZeroCallUsedRegs (BitVector RegsToZero, MachineBasicBlock &MBB) const
	emitZeroCallUsedRegs - Zeros out call used registers.

virtual void	emitCalleeSavedFrameMovesFullCFA (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI) const
	With basic block sections, emit callee saved frame moves for basic blocks that are in a different section.

virtual bool	enableCFIFixup (MachineFunction &MF) const
	Returns true if we may need to fix the unwind information for the function.

virtual void	resetCFIToInitialState (MachineBasicBlock &MBB) const
	Emit CFI instructions that recreate the state of the unwind information upon fucntion entry.

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

virtual bool	stackProbeFunctionModifiesSP () const
	Does the stack probe function call return with a modified stack pointer?

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

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.

virtual bool	spillCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, ArrayRef< CalleeSavedInfo > CSI, const TargetRegisterInfo *TRI) const
	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().

virtual bool	restoreCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, MutableArrayRef< CalleeSavedInfo > CSI, const TargetRegisterInfo *TRI) const
	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().

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".

virtual bool	hasFP (const MachineFunction &MF) const =0
	hasFP - Return true if the specified function should have a dedicated frame pointer register.

virtual bool	hasReservedCallFrame (const MachineFunction &MF) const
	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.

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.

virtual bool	needsFrameIndexResolution (const MachineFunction &MF) const

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

virtual StackOffset	getFrameIndexReferencePreferSP (const MachineFunction &MF, int FI, Register &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`.

virtual StackOffset	getNonLocalFrameIndexReference (const MachineFunction &MF, int FI) const
	getNonLocalFrameIndexReference - This method returns the offset used to reference a frame index location.

virtual StackOffset	getFrameIndexReferenceFromSP (const MachineFunction &MF, int FI) const
	getFrameIndexReferenceFromSP - This method returns the offset from the stack pointer to the slot of the specified index.

virtual void	getCalleeSaves (const MachineFunction &MF, BitVector &SavedRegs) const
	Returns the callee-saved registers as computed by determineCalleeSaves in the BitVector `SavedRegs`.

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

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

virtual void	processFunctionBeforeFrameIndicesReplaced (MachineFunction &MF, RegScavenger *RS=nullptr) const
	processFunctionBeforeFrameIndicesReplaced - This method is called immediately before MO_FrameIndex operands are eliminated, but after the frame is finalized.

virtual unsigned	getWinEHParentFrameOffset (const MachineFunction &MF) const

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

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

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

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

virtual TargetStackID::Value	getStackIDForScalableVectors () const
	Returns the StackID that scalable vectors should be associated with.

virtual bool	isSupportedStackID (TargetStackID::Value ID) const

virtual bool	isProfitableForNoCSROpt (const Function &F) const
	Check if the no-CSR optimisation is profitable for the given function.

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

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

virtual DwarfFrameBase	getDwarfFrameBase (const MachineFunction &MF) const
	Return the frame base information to be encoded in the DWARF subprogram debug info.

virtual void	spillFPBP (MachineFunction &MF) const
	If frame pointer or base pointer is clobbered by an instruction, we should spill/restore it around that instruction.

virtual void	emitRemarks (const MachineFunction &MF, MachineOptimizationRemarkEmitter *ORE) const
	This method is called at the end of prolog/epilog code insertion, so targets can emit remarks based on the final frame layout.

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.

Detailed Description

Definition at line 22 of file AArch64FrameLowering.h.

Constructor & Destructor Documentation

◆ AArch64FrameLowering()

llvm::AArch64FrameLowering::AArch64FrameLowering ( )

inlineexplicit

Definition at line 24 of file AArch64FrameLowering.h.

Member Function Documentation

◆ assignCalleeSavedSpillSlots()

bool AArch64FrameLowering::assignCalleeSavedSpillSlots	(	MachineFunction &	MF,
		const TargetRegisterInfo *	TRI,
		std::vector< CalleeSavedInfo > &	CSI,
		unsigned &	MinCSFrameIndex,
		unsigned &	MaxCSFrameIndex
	)		const

overridevirtual

assignCalleeSavedSpillSlots - Allows target to override spill slot assignment logic.

If implemented, assignCalleeSavedSpillSlots() should assign frame slots to all CSI entries and return true. If this method returns false, spill slots will be assigned using generic implementation. assignCalleeSavedSpillSlots() may add, delete or rearrange elements of CSI.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 3891 of file AArch64FrameLowering.cpp.

References assert(), llvm::MachineFrameInfo::CreateStackObject(), llvm::dbgs(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::TargetRegisterInfo::getMinimalPhysRegClass(), getReg(), llvm::TargetRegisterInfo::getSpillAlign(), llvm::TargetRegisterInfo::getSpillSize(), hasFP(), llvm::AArch64FunctionInfo::hasStackHazardSlotIndex(), llvm::AArch64FunctionInfo::hasSwiftAsyncContext(), I, llvm::AArch64InstrInfo::isFpOrNEON(), isTargetWindows(), LLVM_DEBUG, needsWinCFI(), requiresSaveVG(), llvm::AArch64FunctionInfo::setStackHazardCSRSlotIndex(), llvm::AArch64FunctionInfo::setSwiftAsyncContextFrameIdx(), Size, and StackHazardSize.

◆ canUseAsPrologue()

bool AArch64FrameLowering::canUseAsPrologue ( const MachineBasicBlock & MBB ) const

overridevirtual

Check whether or not the given MBB can be used as a prologue for the target.

The prologue will be inserted first in this basic block. This method is used by the shrink-wrapping pass to decide if MBB will be correctly handled by the target. As soon as the target enable shrink-wrapping without overriding this method, we assume that each basic block is a valid prologue.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 1090 of file AArch64FrameLowering.cpp.

References llvm::LivePhysRegs::available(), findScratchNonCalleeSaveRegister(), llvm::MachineFunction::getInfo(), getLiveRegsForEntryMBB(), llvm::MachineBasicBlock::getParent(), llvm::MachineFunction::getRegInfo(), llvm::AArch64Subtarget::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), llvm::AArch64Subtarget::getTargetLowering(), llvm::AArch64TargetLowering::hasInlineStackProbe(), llvm::AArch64FunctionInfo::hasStackProbing(), llvm::AArch64FunctionInfo::hasSwiftAsyncContext(), llvm::MachineBasicBlock::isLiveIn(), MBB, MRI, and TRI.

◆ canUseRedZone()

bool AArch64FrameLowering::canUseRedZone ( const MachineFunction & MF ) const

Can this function use the red zone for local allocations.

Definition at line 450 of file AArch64FrameLowering.cpp.

References EnableRedZone, llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::AArch64FunctionInfo::getLocalStackSize(), llvm::AArch64TargetLowering::getRedZoneSize(), llvm::MachineFunction::getSubtarget(), getSVEStackSize(), llvm::AArch64Subtarget::getTargetLowering(), llvm::MachineFrameInfo::hasCalls(), hasFP(), and llvm::AArch64Subtarget::isNeonAvailable().

Referenced by emitEpilogue(), emitPrologue(), and resolveFrameOffsetReference().

◆ determineCalleeSaves()

void AArch64FrameLowering::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. This method should not be called by any passes outside of PEI, because it may change state passed in by MF and RS. The preferred interface outside PEI is getCalleeSaves.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 3637 of file AArch64FrameLowering.cpp.

References llvm::CallingConv::AArch64_SVE_VectorCall, llvm::RegScavenger::addScavengingFrameIndex(), llvm::alignTo(), assert(), llvm::AArch64RegisterInfo::cannotEliminateFrame(), contains(), llvm::BitVector::count(), llvm::MachineFrameInfo::CreateStackObject(), llvm::dbgs(), llvm::TargetFrameLowering::determineCalleeSaves(), estimateRSStackSizeLimit(), llvm::MachineFrameInfo::estimateStackSize(), F, findFreePredicateReg(), llvm::AArch64RegisterInfo::getBaseRegister(), llvm::MachineRegisterInfo::getCalleeSavedRegs(), llvm::Function::getCallingConv(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::MachineFrameInfo::getObjectIndexBegin(), llvm::MachineFrameInfo::getObjectOffset(), llvm::AArch64FunctionInfo::getPredicateRegForFillSpill(), llvm::MachineFunction::getRegInfo(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), llvm::CallingConv::GHC, llvm::AArch64RegisterInfo::hasBasePointer(), hasFP(), I, llvm::MachineFrameInfo::isCalleeSavedInfoValid(), llvm::MachineRegisterInfo::isPhysRegUsed(), llvm::AArch64RegisterInfo::isReservedReg(), llvm::AArch64Subtarget::isTargetWindows(), LLVM_DEBUG, MRI, llvm::printReg(), produceCompactUnwindFrame(), RegSize, requiresSaveVG(), llvm::BitVector::reset(), llvm::BitVector::set(), llvm::BitVector::set_bits(), llvm::AArch64FunctionInfo::setPredicateRegForFillSpill(), Size, StackHazardSize, llvm::BitVector::test(), TRI, llvm::CallingConv::Win64, and windowsRequiresStackProbe().

◆ eliminateCallFramePseudoInstr()

MachineBasicBlock::iterator AArch64FrameLowering::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 526 of file AArch64FrameLowering.cpp.

References llvm::alignTo(), assert(), llvm::MachineRegisterInfo::createVirtualRegister(), DL, llvm::emitFrameOffset(), llvm::MachineBasicBlock::erase(), llvm::StackOffset::get(), llvm::StackOffset::getFixed(), llvm::MachineFunction::getFrameInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::MachineFunction::getRegInfo(), llvm::TargetFrameLowering::getStackAlign(), llvm::MachineFunction::getSubtarget(), llvm::AArch64TargetLowering::hasInlineStackProbe(), hasReservedCallFrame(), llvm::MachineFrameInfo::hasVarSizedObjects(), I, MBB, llvm::AArch64::StackProbeMaxUnprobedStack, and TII.

◆ emitEpilogue()

void AArch64FrameLowering::emitEpilogue	(	MachineFunction &	MF,
		MachineBasicBlock &	MBB
	)		const

overridevirtual

Implements llvm::TargetFrameLowering.

Definition at line 2269 of file AArch64FrameLowering.cpp.

◆ emitPrologue()

void AArch64FrameLowering::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 1725 of file AArch64FrameLowering.cpp.

◆ enableCFIFixup()

bool AArch64FrameLowering::enableCFIFixup ( MachineFunction & MF ) const

overridevirtual

Returns true if we may need to fix the unwind information for the function.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2603 of file AArch64FrameLowering.cpp.

References llvm::TargetFrameLowering::enableCFIFixup(), and llvm::MachineFunction::getInfo().

◆ enableShrinkWrapping()

bool llvm::AArch64FrameLowering::enableShrinkWrapping ( const MachineFunction & MF ) const

inlineoverridevirtual

Returns true if the target will correctly handle shrink wrapping.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 81 of file AArch64FrameLowering.h.

◆ enableStackSlotScavenging()

bool AArch64FrameLowering::enableStackSlotScavenging ( const MachineFunction & MF ) const

overridevirtual

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.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 4010 of file AArch64FrameLowering.cpp.

References llvm::MachineFunction::getInfo(), llvm::AArch64FunctionInfo::hasCalleeSaveStackFreeSpace(), hasFP(), llvm::AArch64FunctionInfo::hasStackHazardSlotIndex(), and llvm::AArch64FunctionInfo::hasStreamingModeChanges().

◆ getFrameIndexReference()

StackOffset AArch64FrameLowering::getFrameIndexReference	(	const MachineFunction &	MF,
		int	FI,
		Register &	FrameReg
	)		const

overridevirtual

getFrameIndexReference - Provide a base+offset reference to an FI slot for debug info.

It's the same as what we use for resolving the code-gen references for now. FIXME: This can go wrong when references are SP-relative and simple call frames aren't used.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2613 of file AArch64FrameLowering.cpp.

References llvm::MachineFunction::getFunction(), llvm::Function::hasFnAttribute(), and resolveFrameIndexReference().

Referenced by getFrameIndexReferencePreferSP().

◆ getFrameIndexReferenceFromSP()

StackOffset AArch64FrameLowering::getFrameIndexReferenceFromSP	(	const MachineFunction &	MF,
		int	FI
	)		const

overridevirtual

getFrameIndexReferenceFromSP - This method returns the offset from the stack pointer to the slot of the specified index.

Returns the offset from the stack pointer to the slot of the specified index.

This function serves to provide a comparable offset from a single reference point (the value of the stack-pointer at function entry) that can be used for analysis.

This function serves to provide a comparable offset from a single reference point (the value of the stack-pointer at function entry) that can be used for analysis. This is the default implementation using MachineFrameInfo offsets.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2624 of file AArch64FrameLowering.cpp.

References llvm::StackOffset::get(), llvm::AArch64FunctionInfo::getCalleeSavedStackSize(), llvm::StackOffset::getFixed(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::MachineFrameInfo::getObjectOffset(), llvm::TargetFrameLowering::getOffsetOfLocalArea(), getSVEStackSize(), and llvm::TargetStackID::ScalableVector.

◆ getFrameIndexReferencePreferSP()

StackOffset AArch64FrameLowering::getFrameIndexReferencePreferSP	(	const MachineFunction &	MF,
		int	FI,
		Register &	FrameReg,
		bool	IgnoreSPUpdates
	)		const

overridevirtual

For Win64 AArch64 EH, the offset to the Unwind object is from the SP before the update.

This is easily retrieved as it is exactly the offset that is set in processFunctionBeforeFrameFinalized.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 4664 of file AArch64FrameLowering.cpp.

References llvm::dbgs(), llvm::StackOffset::getFixed(), getFrameIndexReference(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::MachineFrameInfo::getObjectOffset(), llvm::TargetSubtargetInfo::getRegisterInfo(), getStackOffset(), llvm::AArch64FunctionInfo::getStackSizeSVE(), llvm::MachineFunction::getSubtarget(), llvm::TargetRegisterInfo::hasStackRealignment(), llvm::MachineFrameInfo::hasVarSizedObjects(), and LLVM_DEBUG.

◆ getNonLocalFrameIndexReference()

StackOffset AArch64FrameLowering::getNonLocalFrameIndexReference	(	const MachineFunction &	MF,
		int	FI
	)		const

overridevirtual

getNonLocalFrameIndexReference - This method returns the offset used to reference a frame index location.

The offset can be from either FP/BP/SP based on which base register is returned by llvm.localaddress.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2666 of file AArch64FrameLowering.cpp.

References llvm::StackOffset::getFixed(), and getSEHFrameIndexOffset().

Referenced by llvm::AArch64RegisterInfo::eliminateFrameIndex().

◆ getSEHFrameIndexOffset()

int AArch64FrameLowering::getSEHFrameIndexOffset	(	const MachineFunction &	MF,
		int	FI
	)		const

Definition at line 2692 of file AArch64FrameLowering.cpp.

References llvm::StackOffset::getFixed(), getFPOffset(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFrameInfo::getObjectOffset(), llvm::TargetSubtargetInfo::getRegisterInfo(), getStackOffset(), and llvm::MachineFunction::getSubtarget().

Referenced by getNonLocalFrameIndexReference().

◆ getStackIDForScalableVectors()

TargetStackID::Value AArch64FrameLowering::getStackIDForScalableVectors ( ) const

overridevirtual

Returns the StackID that scalable vectors should be associated with.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 419 of file AArch64FrameLowering.cpp.

References llvm::TargetStackID::ScalableVector.

◆ getWinEHFuncletFrameSize()

unsigned AArch64FrameLowering::getWinEHFuncletFrameSize ( const MachineFunction & MF ) const

Funclets only need to account for space for the callee saved registers, as the locals are accounted for in the parent's stack frame.

Definition at line 4694 of file AArch64FrameLowering.cpp.

References llvm::alignTo(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::MachineFrameInfo::getMaxCallFrameSize(), and llvm::TargetFrameLowering::getStackAlign().

Referenced by emitEpilogue(), and emitPrologue().

◆ getWinEHParentFrameOffset()

unsigned AArch64FrameLowering::getWinEHParentFrameOffset ( const MachineFunction & MF ) const

overridevirtual

The parent frame offset (aka dispFrame) is only used on X86_64 to retrieve the parent's frame pointer.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 4687 of file AArch64FrameLowering.cpp.

◆ hasFP()

bool AArch64FrameLowering::hasFP ( const MachineFunction & MF ) const

overridevirtual

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

Implements llvm::TargetFrameLowering.

Definition at line 480 of file AArch64FrameLowering.cpp.

References DefaultSafeSPDisplacement, llvm::TargetOptions::DisableFramePointerElim(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFrameInfo::getMaxCallFrameSize(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), llvm::MachineFunction::getTarget(), llvm::MachineFunction::hasEHFunclets(), llvm::MachineFrameInfo::hasPatchPoint(), llvm::MachineFrameInfo::hasStackMap(), llvm::TargetRegisterInfo::hasStackRealignment(), llvm::MachineFrameInfo::hasVarSizedObjects(), llvm::MachineFrameInfo::isFrameAddressTaken(), llvm::MachineFrameInfo::isMaxCallFrameSizeComputed(), and llvm::TargetMachine::Options.

Referenced by assignCalleeSavedSpillSlots(), canUseRedZone(), determineCalleeSaves(), emitEpilogue(), emitPrologue(), enableStackSlotScavenging(), llvm::AArch64RegisterInfo::getFrameRegister(), llvm::AArch64RegisterInfo::getRegPressureLimit(), llvm::AArch64RegisterInfo::getStrictlyReservedRegs(), llvm::AArch64RegisterInfo::needsFrameBaseReg(), resolveFrameOffsetReference(), restoreCalleeSavedRegisters(), spillCalleeSavedRegisters(), and llvm::AArch64RegisterInfo::useFPForScavengingIndex().

◆ hasReservedCallFrame()

bool AArch64FrameLowering::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 516 of file AArch64FrameLowering.cpp.

References llvm::MachineFunction::getFrameInfo(), and llvm::MachineFrameInfo::hasVarSizedObjects().

Referenced by eliminateCallFramePseudoInstr().

◆ isStackIdSafeForLocalArea()

bool llvm::AArch64FrameLowering::isStackIdSafeForLocalArea ( unsigned StackId ) const

inlineoverridevirtual

This method returns whether or not it is safe for an object with the given stack id to be bundled into the local area.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 118 of file AArch64FrameLowering.h.

References llvm::TargetStackID::ScalableVector.

◆ isSupportedStackID()

bool llvm::AArch64FrameLowering::isSupportedStackID ( TargetStackID::Value ID ) const

inlineoverridevirtual

Reimplemented from llvm::TargetFrameLowering.

Definition at line 107 of file AArch64FrameLowering.h.

References llvm::TargetStackID::Default, llvm::TargetStackID::NoAlloc, and llvm::TargetStackID::ScalableVector.

◆ orderFrameObjects()

void AArch64FrameLowering::orderFrameObjects	(	const MachineFunction &	MF,
		SmallVectorImpl< int > &	objectsToAllocate
	)		const

overridevirtual

Order the symbols in the local stack frame.

The list of objects that we want to order is in objectsToAllocate as indices into the MachineFrameInfo. The array can be reordered in any way upon return. The contents of the array, however, may not be modified (i.e. only their order may be changed). By default, just maintain the original order.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 4777 of file AArch64FrameLowering.cpp.

References llvm::dbgs(), llvm::SmallVectorBase< Size_T >::empty(), llvm::MachineFunction::getFrameInfo(), llvm::MachineOperand::getIndex(), llvm::MachineFunction::getInfo(), getLdStFrameID(), llvm::AArch64FunctionInfo::getStackHazardSlotIndex(), llvm::AArch64FunctionInfo::getTaggedBasePointerIndex(), llvm::AArch64FunctionInfo::hasStackHazardSlotIndex(), llvm::MachineOperand::isFI(), llvm::AArch64InstrInfo::isFpOrNEON(), LLVM_DEBUG, MBB, MI, OpIndex, OrderFrameObjects, llvm::TargetStackID::ScalableVector, and llvm::stable_sort().

◆ processFunctionBeforeFrameFinalized()

void AArch64FrameLowering::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 4143 of file AArch64FrameLowering.cpp.

References llvm::MachineInstrBuilder::addFrameIndex(), llvm::MachineInstrBuilder::addImm(), llvm::MachineInstrBuilder::addReg(), llvm::alignTo(), assert(), llvm::RegScavenger::backward(), llvm::MachineBasicBlock::begin(), llvm::BuildMI(), llvm::MachineFrameInfo::CreateFixedObject(), DL, llvm::MachineBasicBlock::end(), llvm::RegScavenger::enterBasicBlockEnd(), llvm::RegScavenger::FindUnusedReg(), llvm::MachineInstr::FrameSetup, llvm::MachineFunction::front(), getFixedObjectSize(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::getKillRegState(), llvm::TargetFrameLowering::getStackGrowthDirection(), llvm::MachineFunction::getSubtarget(), llvm::MachineFunction::getWinEHFuncInfo(), llvm::MachineFunction::hasEHFunclets(), MBB, MBBI, llvm::AArch64FunctionInfo::setMinMaxSVECSFrameIndex(), llvm::AArch64FunctionInfo::setStackSizeSVE(), llvm::TargetFrameLowering::StackGrowsDown, TII, and llvm::WinEHFuncInfo::UnwindHelpFrameIdx.

◆ processFunctionBeforeFrameIndicesReplaced()

void AArch64FrameLowering::processFunctionBeforeFrameIndicesReplaced	(	MachineFunction &	MF,
		RegScavenger *	RS = `nullptr`
	)		const

overridevirtual

processFunctionBeforeFrameIndicesReplaced - This method is called immediately before MO_FrameIndex operands are eliminated, but after the frame is finalized.

This method is optional.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 4650 of file AArch64FrameLowering.cpp.

References emitVGSaveRestore(), II, requiresSaveVG(), and StackTaggingMergeSetTag.

◆ resetCFIToInitialState()

void AArch64FrameLowering::resetCFIToInitialState ( MachineBasicBlock & MBB ) const

overridevirtual

Emit CFI instructions that recreate the state of the unwind information upon fucntion entry.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 679 of file AArch64FrameLowering.cpp.

References llvm::MachineInstrBuilder::addCFIIndex(), llvm::MachineFunction::addFrameInst(), llvm::MachineBasicBlock::begin(), llvm::BuildMI(), llvm::MCCFIInstruction::cfiDefCfa(), llvm::MCCFIInstruction::createNegateRAState(), DL, llvm::MachineFrameInfo::getCalleeSavedInfo(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::MachineBasicBlock::getParent(), llvm::MachineFunction::getSubtarget(), Info, insertCFISameValue(), MBB, TII, and TRI.

◆ resolveFrameIndexReference()

StackOffset AArch64FrameLowering::resolveFrameIndexReference	(	const MachineFunction &	MF,
		int	FI,
		Register &	FrameReg,
		bool	PreferFP,
		bool	ForSimm
	)		const

Definition at line 2702 of file AArch64FrameLowering.cpp.

References llvm::MachineFunction::getFrameInfo(), llvm::MachineFrameInfo::getObjectOffset(), resolveFrameOffsetReference(), and llvm::TargetStackID::ScalableVector.

Referenced by llvm::AArch64RegisterInfo::eliminateFrameIndex(), and getFrameIndexReference().

◆ resolveFrameOffsetReference()

StackOffset AArch64FrameLowering::resolveFrameOffsetReference	(	const MachineFunction &	MF,
		int64_t	ObjectOffset,
		bool	isFixed,
		bool	isSVE,
		Register &	FrameReg,
		bool	PreferFP,
		bool	ForSimm
	)		const

◆ restoreCalleeSavedRegisters()

bool AArch64FrameLowering::restoreCalleeSavedRegisters	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MI,
		MutableArrayRef< 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 3408 of file AArch64FrameLowering.cpp.

References llvm::MachineInstrBuilder::addImm(), llvm::MachineInstrBuilder::addMemOperand(), llvm::MachineInstrBuilder::addReg(), assert(), llvm::SmallVectorTemplateCommon< T, typename >::begin(), llvm::BuildMI(), computeCalleeSaveRegisterPairs(), llvm::dbgs(), llvm::RegState::Define, DL, llvm::SmallVectorTemplateCommon< T, typename >::end(), llvm::MachineBasicBlock::end(), llvm::MachineInstr::FrameDestroy, llvm::getDefRegState(), llvm::MachinePointerInfo::getFixedStack(), llvm::MachineFunction::getInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::MachineFunction::getMachineMemOperand(), llvm::MachineBasicBlock::getParent(), llvm::AArch64FunctionInfo::getPredicateRegForFillSpill(), llvm::MachineFunction::getSubtarget(), hasFP(), InsertSEH(), LLVM_DEBUG, MBB, MBBI, llvm::MachineMemOperand::MOLoad, needsWinCFI(), llvm::printReg(), llvm::MachineInstrBuilder::setMIFlag(), llvm::MachineInstrBuilder::setMIFlags(), Size, std::swap(), TII, and TRI.

◆ spillCalleeSavedRegisters()

bool AArch64FrameLowering::spillCalleeSavedRegisters	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MI,
		ArrayRef< 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 3165 of file AArch64FrameLowering.cpp.

References llvm::CallingConv::AArch64_SME_ABI_Support_Routines_PreserveMost_From_X1, llvm::MachineInstrBuilder::addExternalSymbol(), llvm::MachineInstrBuilder::addImm(), llvm::MachineBasicBlock::addLiveIn(), llvm::MachineInstrBuilder::addMemOperand(), llvm::MachineInstrBuilder::addReg(), llvm::MachineInstrBuilder::addRegMask(), llvm::any_of(), assert(), llvm::SmallVectorTemplateCommon< T, typename >::begin(), llvm::BuildMI(), computeCalleeSaveRegisterPairs(), llvm::dbgs(), DL, llvm::SmallVectorTemplateCommon< T, typename >::end(), findScratchNonCalleeSaveRegister(), llvm::MachineInstr::FrameSetup, llvm::MachinePointerInfo::getFixedStack(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::MachineFunction::getMachineMemOperand(), llvm::MachineBasicBlock::getParent(), llvm::AArch64FunctionInfo::getPredicateRegForFillSpill(), getPrologueDeath(), llvm::MachineFunction::getRegInfo(), llvm::AArch64FunctionInfo::getStreamingVGIdx(), llvm::MachineFunction::getSubtarget(), hasFP(), llvm::RegState::Implicit, llvm::RegState::ImplicitDefine, InsertSEH(), llvm::MachineBasicBlock::liveins(), LLVM_DEBUG, MBB, MI, llvm::MachineMemOperand::MOStore, MRI, needsWinCFI(), llvm::printReg(), llvm::reverse(), llvm::TargetStackID::ScalableVector, llvm::MachineInstrBuilder::setMIFlag(), llvm::MachineInstrBuilder::setMIFlags(), llvm::MachineFrameInfo::setStackID(), llvm::AArch64FunctionInfo::setStreamingVGIdx(), llvm::AArch64FunctionInfo::setVGIdx(), Size, std::swap(), TII, TRI, and llvm::RegState::Undef.

The documentation for this class was generated from the following files:

lib/Target/AArch64/AArch64FrameLowering.h
lib/Target/AArch64/AArch64FrameLowering.cpp

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ AArch64FrameLowering()

Member Function Documentation

◆ assignCalleeSavedSpillSlots()

◆ canUseAsPrologue()

◆ canUseRedZone()

◆ determineCalleeSaves()

◆ eliminateCallFramePseudoInstr()

◆ emitEpilogue()

◆ emitPrologue()

◆ enableCFIFixup()

◆ enableShrinkWrapping()

◆ enableStackSlotScavenging()

◆ getFrameIndexReference()

◆ getFrameIndexReferenceFromSP()

◆ getFrameIndexReferencePreferSP()

◆ getNonLocalFrameIndexReference()

◆ getSEHFrameIndexOffset()

◆ getStackIDForScalableVectors()

◆ getWinEHFuncletFrameSize()

◆ getWinEHParentFrameOffset()

◆ hasFP()

◆ hasReservedCallFrame()

◆ isStackIdSafeForLocalArea()

◆ isSupportedStackID()

◆ orderFrameObjects()

◆ processFunctionBeforeFrameFinalized()

◆ processFunctionBeforeFrameIndicesReplaced()

◆ resetCFIToInitialState()

◆ resolveFrameIndexReference()

◆ resolveFrameOffsetReference()

◆ restoreCalleeSavedRegisters()

◆ spillCalleeSavedRegisters()