#include "Target/ARM/ARMFrameLowering.h"

Inheritance diagram for llvm::ARMFrameLowering:

Collaboration diagram for llvm::ARMFrameLowering:

[legend]

Public Member Functions
	ARMFrameLowering (const ARMSubtarget &sti)

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	spillCalleeSavedRegisters (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, 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 MI, 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...

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

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

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...

bool	canSimplifyCallFramePseudos (const MachineFunction &MF) const override
	canSimplifyCallFramePseudos - If there is a reserved call frame, the call frame pseudos can be simplified. More...

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

int	ResolveFrameIndexReference (const MachineFunction &MF, int FI, unsigned &FrameReg, int SPAdj) const

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...

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

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

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	isFPCloseToIncomingSP () const
	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...

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

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

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 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. 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...

Protected Attributes
const ARMSubtarget &	STI

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 23 of file ARMFrameLowering.h.

Constructor & Destructor Documentation

◆ ARMFrameLowering()

ARMFrameLowering::ARMFrameLowering ( const ARMSubtarget & sti )

explicit

Definition at line 78 of file ARMFrameLowering.cpp.

Member Function Documentation

◆ adjustForSegmentedStacks()

void ARMFrameLowering::adjustForSegmentedStacks	(	MachineFunction &	MF,
		MachineBasicBlock &	PrologueMBB
	)		const

overridevirtual

Adjust the prologue to have the function use segmented stacks.

This works by adding a check even before the "normal" function prologue.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2133 of file ARMFrameLowering.cpp.

◆ canSimplifyCallFramePseudos()

bool ARMFrameLowering::canSimplifyCallFramePseudos ( const MachineFunction & MF ) const

overridevirtual

canSimplifyCallFramePseudos - If there is a reserved call frame, the call frame pseudos can be simplified.

Unlike most targets, having a FP is not sufficient here since we still may reference some objects via SP even when FP is available in Thumb2 mode.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 141 of file ARMFrameLowering.cpp.

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

Referenced by determineCalleeSaves().

◆ determineCalleeSaves()

void ARMFrameLowering::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 1590 of file ARMFrameLowering.cpp.

◆ emitEpilogue()

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

overridevirtual

Implements llvm::TargetFrameLowering.

Reimplemented in llvm::Thumb1FrameLowering.

Definition at line 766 of file ARMFrameLowering.cpp.

◆ emitPrologue()

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

overridevirtual

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

Implements llvm::TargetFrameLowering.

Reimplemented in llvm::Thumb1FrameLowering.

Definition at line 352 of file ARMFrameLowering.cpp.

◆ enableCalleeSaveSkip()

bool ARMFrameLowering::enableCalleeSaveSkip ( const MachineFunction & MF ) const

overridevirtual

Returns true if the target can safely skip saving callee-saved registers for noreturn nounwind functions.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 91 of file ARMFrameLowering.cpp.

References assert(), llvm::MachineFunction::getFunction(), llvm::Function::hasFnAttribute(), llvm::Attribute::NoReturn, llvm::Attribute::NoUnwind, and llvm::Attribute::UWTable.

◆ enableShrinkWrapping()

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

inlineoverridevirtual

Returns true if the target will correctly handle shrink wrapping.

Reimplemented from llvm::TargetFrameLowering.

Reimplemented in llvm::Thumb1FrameLowering.

Definition at line 64 of file ARMFrameLowering.h.

References MI.

◆ getFrameIndexReference()

int ARMFrameLowering::getFrameIndexReference	(	const MachineFunction &	MF,
		int	FI,
		unsigned &	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 878 of file ARMFrameLowering.cpp.

References ResolveFrameIndexReference().

◆ hasFP()

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

overridevirtual

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.

Implements llvm::TargetFrameLowering.

Definition at line 104 of file ARMFrameLowering.cpp.

References llvm::TargetOptions::DisableFramePointerElim(), llvm::MachineFunction::getFrameInfo(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::MachineFunction::getSubtarget(), llvm::MachineFunction::getTarget(), llvm::MachineFrameInfo::hasVarSizedObjects(), llvm::MachineFrameInfo::isFrameAddressTaken(), llvm::TargetRegisterInfo::needsStackRealignment(), and llvm::TargetMachine::Options.

Referenced by determineCalleeSaves(), llvm::Thumb1FrameLowering::emitPrologue(), emitPrologue(), llvm::ARMBaseRegisterInfo::needsFrameBaseReg(), ResolveFrameIndexReference(), llvm::Thumb1FrameLowering::restoreCalleeSavedRegisters(), and llvm::Thumb1FrameLowering::spillCalleeSavedRegisters().

◆ hasReservedCallFrame()

bool ARMFrameLowering::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.

Reimplemented in llvm::Thumb1FrameLowering.

Definition at line 123 of file ARMFrameLowering.cpp.

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

Referenced by llvm::ARMBaseRegisterInfo::canRealignStack(), canSimplifyCallFramePseudos(), determineCalleeSaves(), llvm::ThumbRegisterInfo::eliminateFrameIndex(), llvm::ARMBaseRegisterInfo::eliminateFrameIndex(), and ResolveFrameIndexReference().

◆ keepFramePointer()

bool ARMFrameLowering::keepFramePointer ( const MachineFunction & MF ) const

overridevirtual

Return true if the target wants to keep the frame pointer regardless of the function attribute "frame-pointer".

Reimplemented from llvm::TargetFrameLowering.

Definition at line 82 of file ARMFrameLowering.cpp.

References llvm::MachineFunction::getSubtarget().

◆ ResolveFrameIndexReference()

int ARMFrameLowering::ResolveFrameIndexReference	(	const MachineFunction &	MF,
		int	FI,
		unsigned &	FrameReg,
		int	SPAdj
	)		const

Definition at line 884 of file ARMFrameLowering.cpp.

References llvm::ARM_AM::add, llvm::MachineInstrBuilder::add(), llvm::MachineInstrBuilder::addImm(), llvm::MachineBasicBlock::addLiveIn(), llvm::MachineInstrBuilder::addReg(), llvm::ARMCC::AL, assert(), llvm::MachineBasicBlock::begin(), llvm::BuildMI(), llvm::SmallVectorImpl< T >::clear(), llvm::MachineInstrBuilder::copyImplicitOps(), llvm::RegState::Define, llvm::SmallVectorBase::empty(), llvm::MachineBasicBlock::end(), first, llvm::MCInstrInfo::get(), llvm::ARM_AM::getAM2Opc(), llvm::ARMBaseRegisterInfo::getBaseRegister(), llvm::getDefRegState(), llvm::MCRegisterInfo::getEncodingValue(), llvm::MachineFunction::getFrameInfo(), llvm::ARMFunctionInfo::getFramePtrSpillOffset(), llvm::ARMBaseRegisterInfo::getFrameRegister(), llvm::MachineFunction::getInfo(), llvm::TargetSubtargetInfo::getInstrInfo(), llvm::getKillRegState(), llvm::MachineFrameInfo::getObjectOffset(), llvm::MachineBasicBlock::getParent(), llvm::CalleeSavedInfo::getReg(), llvm::MachineFunction::getRegInfo(), llvm::TargetSubtargetInfo::getRegisterInfo(), llvm::ARMSubtarget::getRegisterInfo(), llvm::MachineFrameInfo::getStackSize(), llvm::MachineFunction::getSubtarget(), llvm::ARMBaseRegisterInfo::hasBasePointer(), hasFP(), hasReservedCallFrame(), llvm::ARMFunctionInfo::hasStackFrame(), llvm::ARMSubtarget::hasV5TOps(), Info, llvm::MachineFrameInfo::isFixedObjectIndex(), llvm::MachineRegisterInfo::isLiveIn(), llvm::MachineRegisterInfo::isReserved(), llvm::ARMFunctionInfo::isThumb2Function(), llvm::ARMFunctionInfo::isThumbFunction(), MI, MRI, llvm::ARM_AM::no_shift, llvm::predOps(), llvm::SmallVectorTemplateBase< T >::push_back(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), Reg, second, llvm::MachineInstrBuilder::setMIFlags(), llvm::CalleeSavedInfo::setRestored(), llvm::SmallVectorBase::size(), llvm::sort(), llvm::ARMSubtarget::splitFramePushPop(), STI, llvm::MachineBasicBlock::succ_empty(), TII, llvm::ISD::TRAP, and TRI.

Referenced by llvm::ThumbRegisterInfo::eliminateFrameIndex(), llvm::ARMBaseRegisterInfo::eliminateFrameIndex(), and getFrameIndexReference().

◆ restoreCalleeSavedRegisters()

bool ARMFrameLowering::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.

Reimplemented in llvm::Thumb1FrameLowering.

Definition at line 1448 of file ARMFrameLowering.cpp.

References emitAlignedDPRCS2Restores(), llvm::ARMFunctionInfo::getArgRegsSaveSize(), llvm::MachineFunction::getInfo(), llvm::ARMFunctionInfo::getNumAlignedDPRCS2Regs(), llvm::MachineBasicBlock::getParent(), llvm::isARMArea1Register(), llvm::isARMArea2Register(), llvm::isARMArea3Register(), and llvm::ARMFunctionInfo::isThumbFunction().

◆ spillCalleeSavedRegisters()

bool ARMFrameLowering::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.

Reimplemented in llvm::Thumb1FrameLowering.

Definition at line 1417 of file ARMFrameLowering.cpp.

References emitAlignedDPRCS2Spills(), llvm::MachineInstr::FrameSetup, llvm::MachineFunction::getInfo(), llvm::ARMFunctionInfo::getNumAlignedDPRCS2Regs(), llvm::MachineBasicBlock::getParent(), llvm::isARMArea1Register(), llvm::isARMArea2Register(), llvm::isARMArea3Register(), and llvm::ARMFunctionInfo::isThumbFunction().