#include "Target/X86/X86FrameLowering.h"

Inheritance diagram for llvm::X86FrameLowering:

Collaboration diagram for llvm::X86FrameLowering:

[legend]

Public Member Functions
	X86FrameLowering (const X86Subtarget &STI, unsigned StackAlignOverride)

void	emitStackProbe (MachineFunction &MF, MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, const DebugLoc &DL, bool InProlog) const
	Emit target stack probe code. More...

void	inlineStackProbe (MachineFunction &MF, MachineBasicBlock &PrologMBB) const override
	Replace a StackProbe inline-stub with the actual probe code inline. More...

void	emitCalleeSavedFrameMoves (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, const DebugLoc &DL) const

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

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

void	adjustForHiPEPrologue (MachineFunction &MF, MachineBasicBlock &PrologueMBB) const override
	Erlang programs may need a special prologue to handle the stack size they might need at runtime. More...

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

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

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	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...

bool	needsFrameIndexResolution (const MachineFunction &MF) const override

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

int	getFrameIndexReferenceSP (const MachineFunction &MF, int FI, unsigned &SPReg, int Adjustment) const

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

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...

int	mergeSPUpdates (MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI, bool doMergeWithPrevious) const
	Check the instruction before/after the passed instruction. More...

void	emitSPUpdate (MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI, const DebugLoc &DL, int64_t NumBytes, bool InEpilogue) const
	Emit a series of instructions to increment / decrement the stack pointer by a constant value. More...

bool	canUseLEAForSPInEpilogue (const MachineFunction &MF) const
	Check that LEA can be used on SP in an epilogue sequence for `MF`. More...

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

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

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

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

void	BuildCFI (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, const DebugLoc &DL, const MCCFIInstruction &CFIInst) const
	Wraps up getting a CFI index and building a MachineInstr for it. More...

MachineBasicBlock::iterator	restoreWin32EHStackPointers (MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, const DebugLoc &DL, bool RestoreSP=false) const
	Sets up EBP and optionally ESI based on the incoming EBP value. More...

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

unsigned	getInitialCFARegister (const MachineFunction &MF) const override
	Return initial CFA register value i.e. 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 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 bool	enableCalleeSaveSkip (const MachineFunction &MF) const
	Returns true if the target can safely skip saving callee-saved registers for noreturn nounwind functions. 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...

Public Attributes
const X86Subtarget &	STI

const X86InstrInfo &	TII

const X86RegisterInfo *	TRI

unsigned	SlotSize

bool	Is64Bit
	Is64Bit implies that x86_64 instructions are available. More...

bool	IsLP64

bool	Uses64BitFramePtr
	True if the 64-bit frame or stack pointer should be used. More...

unsigned	StackPtr

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 27 of file X86FrameLowering.h.

Constructor & Destructor Documentation

◆ X86FrameLowering()

X86FrameLowering::X86FrameLowering	(	const X86Subtarget &	STI,
		unsigned	StackAlignOverride
	)

Definition at line 38 of file X86FrameLowering.cpp.

References llvm::X86RegisterInfo::getSlotSize(), llvm::X86RegisterInfo::getStackRegister(), Is64Bit, llvm::X86Subtarget::is64Bit(), IsLP64, llvm::X86Subtarget::isTarget64BitLP64(), llvm::X86Subtarget::isTargetNaCl64(), SlotSize, StackPtr, TRI, and Uses64BitFramePtr.

Member Function Documentation

◆ adjustForHiPEPrologue()

void X86FrameLowering::adjustForHiPEPrologue	(	MachineFunction &	MF,
		MachineBasicBlock &	PrologueMBB
	)		const

overridevirtual

Erlang programs may need a special prologue to handle the stack size they might need at runtime.

That is because Erlang/OTP does not implement a C stack but uses a custom implementation of hybrid stack/heap architecture. (for more information see Eric Stenman's Ph.D. thesis: http://publications.uu.se/uu/fulltext/nbn_se_uu_diva-2688.pdf)

CheckStack: temp0 = sp - MaxStack if( temp0 < SP_LIMIT(P) ) goto IncStack else goto OldStart OldStart: ... IncStack: call inc_stack # doubles the stack space temp0 = sp - MaxStack if( temp0 < SP_LIMIT(P) ) goto IncStack else goto OldStart

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2526 of file X86FrameLowering.cpp.

◆ adjustForSegmentedStacks()

void X86FrameLowering::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 2245 of file X86FrameLowering.cpp.

◆ assignCalleeSavedSpillSlots()

bool X86FrameLowering::assignCalleeSavedSpillSlots	(	MachineFunction &	MF,
		const TargetRegisterInfo *	TRI,
		std::vector< CalleeSavedInfo > &	CSI
	)		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 1927 of file X86FrameLowering.cpp.

References llvm::abs(), llvm::AMDGPU::HSAMD::Kernel::Arg::Key::Align, contains(), llvm::MachineFrameInfo::CreateFixedObject(), llvm::MachineFrameInfo::CreateFixedSpillStackObject(), llvm::MachineFrameInfo::CreateSpillStackObject(), llvm::MachineFrameInfo::ensureMaxAlignment(), llvm::MachineFunction::getFrameInfo(), llvm::TargetRegisterInfo::getFrameRegister(), llvm::MachineFunction::getInfo(), llvm::TargetRegisterInfo::getMinimalPhysRegClass(), llvm::TargetFrameLowering::getOffsetOfLocalArea(), llvm::TargetRegisterInfo::getSpillAlignment(), llvm::TargetRegisterInfo::getSpillSize(), llvm::X86MachineFunctionInfo::getTCReturnAddrDelta(), llvm::X86Subtarget::hasBWI(), llvm::MachineFunction::hasEHFunclets(), hasFP(), llvm::MVT::Other, llvm::TargetRegisterInfo::regsOverlap(), llvm::X86MachineFunctionInfo::setCalleeSavedFrameSize(), llvm::MachineFrameInfo::setCVBytesOfCalleeSavedRegisters(), llvm::X86MachineFunctionInfo::setHasSEHFramePtrSave(), llvm::X86MachineFunctionInfo::setSEHFramePtrSaveIndex(), Size, SlotSize, STI, llvm::MVT::v16i1, and llvm::MVT::v64i1.

◆ BuildCFI()

void X86FrameLowering::BuildCFI	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MBBI,
		const DebugLoc &	DL,
		const MCCFIInstruction &	CFIInst
	)		const

Wraps up getting a CFI index and building a MachineInstr for it.

Definition at line 451 of file X86FrameLowering.cpp.

References llvm::MachineFunction::addFrameInst(), llvm::BuildMI(), llvm::MachineBasicBlock::getParent(), and TII.

Referenced by eliminateCallFramePseudoInstr(), emitCalleeSavedFrameMoves(), emitEpilogue(), emitPrologue(), and ExpandMOVImmSExti8().

◆ canSimplifyCallFramePseudos()

bool X86FrameLowering::canSimplifyCallFramePseudos ( const MachineFunction & MF ) const

overridevirtual

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

Having a FP, as in the default implementation, is not sufficient here since we can't always use it. Use a more nuanced condition.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 62 of file X86FrameLowering.cpp.

References llvm::X86RegisterInfo::hasBasePointer(), hasFP(), hasReservedCallFrame(), and TRI.

◆ canUseAsEpilogue()

bool X86FrameLowering::canUseAsEpilogue ( const MachineBasicBlock & MBB ) const

overridevirtual

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

The epilogue will be inserted before the first terminator of that block. This method is used by the shrink-wrapping pass to decide if MBB will be correctly handled by the target.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2856 of file X86FrameLowering.cpp.

References assert(), canUseLEAForSPInEpilogue(), flagsNeedToBePreservedBeforeTheTerminators(), llvm::MachineBasicBlock::getParent(), llvm::MachineBasicBlock::isReturnBlock(), llvm::X86Subtarget::isTargetWin64(), STI, and llvm::MachineBasicBlock::succ_empty().

◆ canUseAsPrologue()

bool X86FrameLowering::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 2850 of file X86FrameLowering.cpp.

References assert(), llvm::MachineBasicBlock::getParent(), llvm::MachineBasicBlock::isLiveIn(), and TRI.

◆ canUseLEAForSPInEpilogue()

bool X86FrameLowering::canUseLEAForSPInEpilogue ( const MachineFunction & MF ) const

Check that LEA can be used on SP in an epilogue sequence for MF.

Definition at line 1501 of file X86FrameLowering.cpp.

References llvm::TargetMachine::getMCAsmInfo(), llvm::MachineFunction::getTarget(), hasFP(), and llvm::MCAsmInfo::usesWindowsCFI().

Referenced by canUseAsEpilogue(), and emitSPUpdate().

◆ determineCalleeSaves()

void X86FrameLowering::determineCalleeSaves	(	MachineFunction &	MF,
		BitVector &	SavedRegs,
		RegScavenger *	RS = `nullptr`
	)		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 2179 of file X86FrameLowering.cpp.

References llvm::TargetFrameLowering::determineCalleeSaves(), llvm::X86RegisterInfo::getBaseRegister(), llvm::getX86SubSuperRegister(), llvm::X86RegisterInfo::hasBasePointer(), llvm::X86Subtarget::isTarget64BitILP32(), llvm::BitVector::set(), STI, and TRI.

◆ eliminateCallFramePseudoInstr()

MachineBasicBlock::iterator X86FrameLowering::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 2738 of file X86FrameLowering.cpp.

References llvm::alignTo(), B, llvm::MachineBasicBlock::begin(), BuildCFI(), llvm::MCCFIInstruction::createAdjustCfaOffset(), llvm::MCCFIInstruction::createGnuArgsSize(), llvm::DwarfCFI, llvm::MachineBasicBlock::end(), llvm::MachineBasicBlock::erase(), F(), llvm::X86InstrInfo::getFrameAdjustment(), llvm::MachineFunction::getFunction(), llvm::X86MachineFunctionInfo::getHasPushSequences(), llvm::MachineFunction::getInfo(), llvm::MachineFunction::getLandingPads(), llvm::TargetMachine::getMCAsmInfo(), llvm::MachineFunction::getMMI(), llvm::TargetFrameLowering::getStackAlignment(), llvm::MachineFunction::getTarget(), llvm::MachineModuleInfo::hasDebugInfo(), hasFP(), hasReservedCallFrame(), I, mergeSPUpdates(), llvm::Function::needsUnwindTableEntry(), llvm::Function::optForMinSize(), llvm::skipDebugInstructionsForward(), llvm::ARM::WinEH::StackAdjustment(), TII, and llvm::MCAsmInfo::usesWindowsCFI().

Referenced by adjustForHiPEPrologue().

◆ emitCalleeSavedFrameMoves()

void X86FrameLowering::emitCalleeSavedFrameMoves	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MBBI,
		const DebugLoc &	DL
	)		const

Definition at line 461 of file X86FrameLowering.cpp.

References BuildCFI(), llvm::MCCFIInstruction::createOffset(), E, llvm::MachineFrameInfo::getCalleeSavedInfo(), llvm::MachineModuleInfo::getContext(), llvm::MCRegisterInfo::getDwarfRegNum(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getMMI(), llvm::MachineFrameInfo::getObjectOffset(), llvm::MachineBasicBlock::getParent(), llvm::MCContext::getRegisterInfo(), I, MRI, and Reg.

◆ emitEpilogue()

void X86FrameLowering::emitEpilogue	(	MachineFunction &	MF,
		MachineBasicBlock &	MBB
	)		const

overridevirtual

Implements llvm::TargetFrameLowering.

Definition at line 1580 of file X86FrameLowering.cpp.

References llvm::addRegOffset(), llvm::alignTo(), assert(), llvm::MachineBasicBlock::begin(), BuildCFI(), llvm::BuildMI(), calculateSetFPREG(), llvm::ISD::CATCHRET, llvm::MCCFIInstruction::createDefCfa(), llvm::MCCFIInstruction::createDefCfaOffset(), emitSPUpdate(), llvm::MachineBasicBlock::end(), llvm::N86::ESP, false, llvm::MachineInstr::FrameDestroy, llvm::X86MachineFunctionInfo::getCalleeSavedFrameSize(), llvm::MachineBasicBlock::getFirstTerminator(), llvm::MachineFunction::getFrameInfo(), llvm::X86RegisterInfo::getFrameRegister(), llvm::MachineFunction::getFunction(), llvm::MachineFunction::getInfo(), getLEArOpcode(), llvm::TargetMachine::getMCAsmInfo(), llvm::MachineFunction::getMMI(), llvm::MachineFrameInfo::getStackSize(), llvm::MachineFunction::getTarget(), llvm::TargetMachine::getTargetTriple(), llvm::X86MachineFunctionInfo::getTCReturnAddrDelta(), llvm::getX86SubSuperRegister(), llvm::MachineModuleInfo::hasDebugInfo(), hasFP(), llvm::MachineFrameInfo::hasVarSizedObjects(), llvm::MachineFunction::hasWinCFI(), Is64Bit, isFuncletReturnInstr(), llvm::Triple::isOSDarwin(), llvm::Triple::isOSWindows(), isTailCallOpcode(), llvm::X86Subtarget::isTarget64BitILP32(), mergeSPUpdates(), llvm::Function::needsUnwindTableEntry(), SlotSize, StackPtr, STI, llvm::MCID::Terminator, TII, TRI, Uses64BitFramePtr, and llvm::MCAsmInfo::usesWindowsCFI().

◆ emitPrologue()

void X86FrameLowering::emitPrologue	(	MachineFunction &	MF,
		MachineBasicBlock &	MBB
	)		const

overridevirtual

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

emitPrologue - Push callee-saved registers onto the stack, which automatically adjust the stack pointer.

Adjust the stack pointer to allocate space for local variables. Also emit labels used by the exception handler to generate the exception handling frames.

Implements llvm::TargetFrameLowering.

Definition at line 960 of file X86FrameLowering.cpp.

◆ emitSPUpdate()

void X86FrameLowering::emitSPUpdate	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator &	MBBI,
		const DebugLoc &	DL,
		int64_t	NumBytes,
		bool	InEpilogue
	)		const

Emit a series of instructions to increment / decrement the stack pointer by a constant value.

emitSPUpdate - Emit a series of instructions to increment / decrement the stack pointer by a constant value.

Definition at line 250 of file X86FrameLowering.cpp.

References llvm::MachineInstrBuilder::addImm(), llvm::MachineInstrBuilder::addReg(), llvm::addRegOffset(), assert(), llvm::BuildMI(), canUseLEAForSPInEpilogue(), llvm::N86::EAX, findDeadCallerSavedReg(), flagsNeedToBePreservedBeforeTheTerminators(), llvm::MachineInstr::FrameDestroy, llvm::MachineInstr::FrameSetup, getADDriOpcode(), getADDrrOpcode(), llvm::getDefRegState(), getLEArOpcode(), llvm::MachineInstr::getOperand(), llvm::MachineBasicBlock::getParent(), getSUBriOpcode(), getSUBrrOpcode(), llvm::getUndefRegState(), Is64Bit, isEAXLiveIn(), llvm::MachineBasicBlock::isLiveIn(), llvm::RegState::Kill, MI, Reg, llvm::MachineOperand::setIsDead(), llvm::MachineInstrBuilder::setMIFlag(), SlotSize, StackPtr, STI, TII, TRI, llvm::X86Subtarget::useLeaForSP(), and Uses64BitFramePtr.

Referenced by emitEpilogue(), and emitPrologue().

◆ emitStackProbe()

void X86FrameLowering::emitStackProbe	(	MachineFunction &	MF,
		MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MBBI,
		const DebugLoc &	DL,
		bool	InProlog
	)		const

Emit target stack probe code.

This is required for all large stack allocations on Windows. The caller is required to materialize the number of bytes to probe in RAX/EAX.

Definition at line 485 of file X86FrameLowering.cpp.

References llvm::MachineFunction::getSubtarget(), llvm::X86Subtarget::isTargetWindowsCoreCLR(), and STI.

◆ enableShrinkWrapping()

bool X86FrameLowering::enableShrinkWrapping ( const MachineFunction & MF ) const

overridevirtual

Returns true if the target will correctly handle shrink wrapping.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2876 of file X86FrameLowering.cpp.

References llvm::Function::getCallingConv(), llvm::MachineFunction::getFunction(), llvm::Function::hasFnAttribute(), hasFP(), llvm::CallingConv::HiPE, llvm::Attribute::NoUnwind, and llvm::MachineFunction::shouldSplitStack().

◆ getFrameIndexReference()

int X86FrameLowering::getFrameIndexReference	(	const MachineFunction &	MF,
		int	FI,
		unsigned &	FrameReg
	)		const

overridevirtual

getFrameIndexReference - This method should return the base register and offset used to reference a frame index location.

Returns the displacement from the frame register to the stack frame of the specified index, along with the frame register used (in output arg FrameReg).

The offset is returned directly, and the base register is returned via FrameReg.

This is the default implementation which is overridden for some targets.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 1750 of file X86FrameLowering.cpp.

References assert(), calculateSetFPREG(), llvm::X86RegisterInfo::getBaseRegister(), llvm::X86MachineFunctionInfo::getCalleeSavedFrameSize(), llvm::X86MachineFunctionInfo::getFAIndex(), llvm::MachineFunction::getFrameInfo(), llvm::X86RegisterInfo::getFramePtr(), llvm::X86RegisterInfo::getFrameRegister(), llvm::MachineFunction::getInfo(), llvm::TargetMachine::getMCAsmInfo(), llvm::MachineFrameInfo::getObjectAlignment(), llvm::MachineFrameInfo::getObjectOffset(), llvm::TargetFrameLowering::getOffsetOfLocalArea(), llvm::X86MachineFunctionInfo::getRestoreBasePointer(), llvm::X86RegisterInfo::getStackRegister(), llvm::MachineFrameInfo::getStackSize(), llvm::MachineFunction::getTarget(), llvm::X86MachineFunctionInfo::getTCReturnAddrDelta(), llvm::X86RegisterInfo::hasBasePointer(), llvm::MachineFrameInfo::hasCalls(), hasFP(), llvm::MachineFrameInfo::isFixedObjectIndex(), SlotSize, TRI, and llvm::MCAsmInfo::usesWindowsCFI().

Referenced by llvm::X86RegisterInfo::eliminateFrameIndex(), getFrameIndexReferencePreferSP(), and restoreWin32EHStackPointers().

◆ getFrameIndexReferencePreferSP()

int X86FrameLowering::getFrameIndexReferencePreferSP	(	const MachineFunction &	MF,
		int	FI,
		unsigned &	FrameReg,
		bool	IgnoreSPUpdates
	)		const

overridevirtual

Same as getFrameIndexReference, except that the stack pointer (as opposed to the frame pointer) will be the preferred value for FrameReg.

This is generally used for emitting statepoint or EH tables that use offsets from RSP. If IgnoreSPUpdates is true, the returned offset is only guaranteed to be valid with respect to the value of SP at the end of the prologue.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 1844 of file X86FrameLowering.cpp.

References assert(), getFrameIndexReference(), getFrameIndexReferenceSP(), llvm::MachineFunction::getFrameInfo(), llvm::TargetSubtargetInfo::getFrameLowering(), llvm::MachineFunction::getInfo(), llvm::MachineFrameInfo::getStackSize(), llvm::MachineFunction::getSubtarget(), llvm::X86MachineFunctionInfo::getTCReturnAddrDelta(), llvm::TargetFrameLowering::hasReservedCallFrame(), llvm::MachineFrameInfo::isFixedObjectIndex(), llvm::X86Subtarget::isTargetWin64(), STI, and TRI.

Referenced by isFuncletReturnInstr().

◆ getFrameIndexReferenceSP()

int X86FrameLowering::getFrameIndexReferenceSP	(	const MachineFunction &	MF,
		int	FI,
		unsigned &	SPReg,
		int	Adjustment
	)		const

Definition at line 1835 of file X86FrameLowering.cpp.

References llvm::MachineFunction::getFrameInfo(), llvm::MachineFrameInfo::getObjectOffset(), llvm::TargetFrameLowering::getOffsetOfLocalArea(), llvm::X86RegisterInfo::getStackRegister(), and TRI.

Referenced by llvm::X86RegisterInfo::eliminateFrameIndex(), and getFrameIndexReferencePreferSP().

◆ getInitialCFAOffset()

int X86FrameLowering::getInitialCFAOffset ( const MachineFunction & MF ) const

overridevirtual

Return initial CFA offset value i.e.

the one valid at the beginning of the function (before any stack operations).

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2951 of file X86FrameLowering.cpp.

References llvm::X86RegisterInfo::getSlotSize(), and TRI.

◆ getInitialCFARegister()

unsigned X86FrameLowering::getInitialCFARegister ( const MachineFunction & MF ) const

overridevirtual

Return initial CFA register value i.e.

the one valid at the beginning of the function (before any stack operations).

Reimplemented from llvm::TargetFrameLowering.

Definition at line 2955 of file X86FrameLowering.cpp.

References B, StackPtr, and TRI.

◆ getWinEHParentFrameOffset()

unsigned X86FrameLowering::getWinEHParentFrameOffset ( const MachineFunction & MF ) const

overridevirtual

Reimplemented from llvm::TargetFrameLowering.

Definition at line 3104 of file X86FrameLowering.cpp.

References llvm::MachineFunction::getInfo(), and SlotSize.

◆ hasFP()

bool X86FrameLowering::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 84 of file X86FrameLowering.cpp.

References llvm::MachineFunction::callsEHReturn(), llvm::MachineFunction::callsUnwindInit(), llvm::TargetOptions::DisableFramePointerElim(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), llvm::MachineFunction::getTarget(), llvm::MachineFrameInfo::hasCopyImplyingStackAdjustment(), llvm::MachineFunction::hasEHFunclets(), llvm::MachineFrameInfo::hasOpaqueSPAdjustment(), llvm::MachineFrameInfo::hasPatchPoint(), llvm::MachineFrameInfo::hasStackMap(), llvm::MachineFrameInfo::hasVarSizedObjects(), llvm::MachineFrameInfo::isFrameAddressTaken(), llvm::TargetMachine::Options, and TRI.

Referenced by assignCalleeSavedSpillSlots(), canSimplifyCallFramePseudos(), canUseLEAForSPInEpilogue(), eliminateCallFramePseudoInstr(), emitEpilogue(), llvm::X86AsmPrinter::EmitInstruction(), emitPrologue(), enableShrinkWrapping(), ExpandMOVImmSExti8(), getFrameIndexReference(), llvm::X86RegisterInfo::getFrameRegister(), llvm::X86RegisterInfo::getPointerRegClass(), llvm::X86RegisterInfo::getRegPressureLimit(), llvm::X86RegisterInfo::getReservedRegs(), inlineStackProbe(), and orderFrameObjects().

◆ hasReservedCallFrame()

bool X86FrameLowering::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 52 of file X86FrameLowering.cpp.

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

Referenced by canSimplifyCallFramePseudos(), and eliminateCallFramePseudoInstr().

◆ inlineStackProbe()

void X86FrameLowering::inlineStackProbe	(	MachineFunction &	MF,
		MachineBasicBlock &	PrologMBB
	)		const

overridevirtual

Replace a StackProbe inline-stub with the actual probe code inline.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 501 of file X86FrameLowering.cpp.

◆ mergeSPUpdates()

int X86FrameLowering::mergeSPUpdates	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator &	MBBI,
		bool	doMergeWithPrevious
	)		const

Check the instruction before/after the passed instruction.

If it is an ADD/SUB/LEA instruction it is deleted argument and the stack adjustment is returned as a positive value for ADD/LEA and a negative for SUB.

Definition at line 395 of file X86FrameLowering.cpp.

References assert(), llvm::MachineBasicBlock::begin(), llvm::MachineBasicBlock::end(), llvm::MachineBasicBlock::erase(), llvm::skipDebugInstructionsBackward(), llvm::skipDebugInstructionsForward(), and StackPtr.

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

◆ needsFrameIndexResolution()

bool X86FrameLowering::needsFrameIndexResolution ( const MachineFunction & MF ) const

overridevirtual

Reimplemented from llvm::TargetFrameLowering.

Definition at line 76 of file X86FrameLowering.cpp.

References llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getInfo(), and llvm::MachineFrameInfo::hasStackObjects().

◆ orderFrameObjects()

void X86FrameLowering::orderFrameObjects	(	const MachineFunction &	MF,
		SmallVectorImpl< int > &	ObjectsToAllocate
	)		const

overridevirtual

Order the symbols in the local stack.

We want to place the local stack objects in some sort of sensible order. The heuristic we use is to try and pack them according to static number of uses and size in order to minimize code size.

Reimplemented from llvm::TargetFrameLowering.

Definition at line 3031 of file X86FrameLowering.cpp.

References llvm::SmallVectorBase::empty(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFrameInfo::getObjectAlignment(), llvm::MachineFrameInfo::getObjectIndexEnd(), llvm::MachineFrameInfo::getObjectSize(), hasFP(), MI, llvm::reverse(), and TRI.

◆ processFunctionBeforeFrameFinalized()

void X86FrameLowering::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 3116 of file X86FrameLowering.cpp.

References llvm::abs(), llvm::addFrameReference(), llvm::MachineInstrBuilder::addImm(), llvm::AMDGPU::HSAMD::Kernel::Arg::Key::Align, llvm::MachineBasicBlock::begin(), llvm::BuildMI(), llvm::WinEHHandlerType::CatchObj, llvm::classifyEHPersonality(), llvm::MachineFrameInfo::CreateFixedObject(), llvm::MachineBasicBlock::end(), F(), llvm::MachineBasicBlock::findDebugLoc(), llvm::ISD::FrameIndex, llvm::WinEHHandlerType::FrameIndex, llvm::MachineInstr::FrameSetup, llvm::MachineFunction::front(), llvm::MachineFunction::getFrameInfo(), llvm::MachineFunction::getFunction(), llvm::MachineFrameInfo::getObjectAlignment(), llvm::MachineFrameInfo::getObjectIndexBegin(), llvm::MachineFrameInfo::getObjectOffset(), llvm::MachineFrameInfo::getObjectSize(), llvm::Function::getPersonalityFn(), llvm::MachineFunction::getWinEHFuncInfo(), H, llvm::WinEHTryBlockMapEntry::HandlerArray, llvm::MachineFunction::hasEHFunclets(), I, llvm::X86Subtarget::is64Bit(), llvm::MSVC_CXX, llvm::MachineFunction::setHasWinCFI(), llvm::MachineFrameInfo::setObjectOffset(), SlotSize, STI, TII, llvm::WinEHFuncInfo::TryBlockMap, and llvm::WinEHFuncInfo::UnwindHelpFrameIdx.

◆ restoreCalleeSavedRegisters()

bool X86FrameLowering::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 2124 of file X86FrameLowering.cpp.

References llvm::BuildMI(), llvm::ISD::CATCHRET, llvm::classifyEHPersonality(), contains(), llvm::MachineBasicBlock::end(), F(), llvm::MachineBasicBlock::findDebugLoc(), llvm::MachineInstr::FrameDestroy, llvm::MachineFunction::getFunction(), llvm::TargetRegisterInfo::getMinimalPhysRegClass(), llvm::MachineBasicBlock::getParent(), llvm::Function::getPersonalityFn(), llvm::X86Subtarget::hasBWI(), llvm::X86Subtarget::is32Bit(), llvm::X86Subtarget::is64Bit(), llvm::isAsynchronousEHPersonality(), isFuncletReturnInstr(), llvm::X86Subtarget::isOSWindows(), llvm::X86InstrInfo::loadRegFromStackSlot(), llvm::MVT::Other, Reg, STI, TII, llvm::MVT::v16i1, and llvm::MVT::v64i1.

◆ restoreWin32EHStackPointers()

MachineBasicBlock::iterator X86FrameLowering::restoreWin32EHStackPointers	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MBBI,
		const DebugLoc &	DL,
		bool	RestoreSP = `false`
	)		const

Sets up EBP and optionally ESI based on the incoming EBP value.

Only needed for 32-bit. Used in funclet prologues and at catchret destinations.

Definition at line 2889 of file X86FrameLowering.cpp.

References llvm::MachineInstrBuilder::addImm(), llvm::addRegOffset(), assert(), llvm::BuildMI(), llvm::WinEHFuncInfo::EHRegNodeEndOffset, llvm::WinEHFuncInfo::EHRegNodeFrameIndex, llvm::N86::ESP, llvm::MachineInstr::FrameSetup, getADDriOpcode(), llvm::X86RegisterInfo::getBaseRegister(), getFrameIndexReference(), llvm::X86RegisterInfo::getFrameRegister(), llvm::X86MachineFunctionInfo::getHasSEHFramePtrSave(), llvm::MachineInstr::getOperand(), llvm::MachineBasicBlock::getParent(), llvm::X86MachineFunctionInfo::getSEHFramePtrSaveIndex(), llvm::X86Subtarget::is32Bit(), llvm::X86Subtarget::isTargetWin32(), llvm::X86Subtarget::isTargetWindowsMSVC(), llvm_unreachable, llvm::MachineOperand::setIsDead(), llvm::MachineInstrBuilder::setMIFlag(), STI, TII, TRI, and Uses64BitFramePtr.

◆ spillCalleeSavedRegisters()

bool X86FrameLowering::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 2022 of file X86FrameLowering.cpp.

References llvm::MachineInstrBuilder::addImm(), llvm::MachineBasicBlock::addLiveIn(), llvm::MachineInstrBuilder::addMBB(), llvm::MachineInstrBuilder::addReg(), assert(), llvm::BuildMI(), llvm::classifyEHPersonality(), contains(), llvm::N86::EAX, llvm::MachineBasicBlock::findDebugLoc(), llvm::MachineInstr::FrameSetup, llvm::MachineInstr::getDebugLoc(), llvm::MachineFunction::getFunction(), llvm::getKillRegState(), llvm::MachineOperand::getMBB(), llvm::TargetRegisterInfo::getMinimalPhysRegClass(), llvm::MachineInstr::getOperand(), llvm::MachineBasicBlock::getParent(), llvm::Function::getPersonalityFn(), llvm::MachineFunction::getRegInfo(), llvm::X86Subtarget::hasBWI(), llvm::X86Subtarget::is32Bit(), llvm::X86Subtarget::is64Bit(), llvm::isAsynchronousEHPersonality(), llvm::MachineBasicBlock::isEHFuncletEntry(), llvm::MachineRegisterInfo::isLiveIn(), llvm::X86Subtarget::isOSWindows(), llvm::MCRegAliasIterator::isValid(), MI, MRI, llvm::MVT::Other, llvm::MachineBasicBlock::setHasAddressTaken(), STI, llvm::X86InstrInfo::storeRegToStackSlot(), TII, llvm::MVT::v16i1, and llvm::MVT::v64i1.

Member Data Documentation

◆ Is64Bit

bool llvm::X86FrameLowering::Is64Bit

Is64Bit implies that x86_64 instructions are available.

Definition at line 40 of file X86FrameLowering.h.

Referenced by adjustForHiPEPrologue(), adjustForSegmentedStacks(), emitEpilogue(), emitPrologue(), emitSPUpdate(), inlineStackProbe(), and X86FrameLowering().

◆ IsLP64

bool llvm::X86FrameLowering::IsLP64

Definition at line 42 of file X86FrameLowering.h.

Referenced by adjustForHiPEPrologue(), adjustForSegmentedStacks(), and X86FrameLowering().

◆ SlotSize

unsigned llvm::X86FrameLowering::SlotSize

Definition at line 37 of file X86FrameLowering.h.

Referenced by adjustForHiPEPrologue(), assignCalleeSavedSpillSlots(), calculateSetFPREG(), emitEpilogue(), emitPrologue(), emitSPUpdate(), getFrameIndexReference(), getWinEHParentFrameOffset(), isFuncletReturnInstr(), processFunctionBeforeFrameFinalized(), and X86FrameLowering().

◆ StackPtr

unsigned llvm::X86FrameLowering::StackPtr

Definition at line 49 of file X86FrameLowering.h.

Referenced by emitEpilogue(), emitPrologue(), emitSPUpdate(), getInitialCFARegister(), mergeSPUpdates(), and X86FrameLowering().

◆ STI

const X86Subtarget& llvm::X86FrameLowering::STI

Definition at line 33 of file X86FrameLowering.h.

Referenced by adjustForHiPEPrologue(), adjustForSegmentedStacks(), assignCalleeSavedSpillSlots(), canUseAsEpilogue(), determineCalleeSaves(), emitEpilogue(), emitPrologue(), emitSPUpdate(), emitStackProbe(), getFrameIndexReferencePreferSP(), inlineStackProbe(), processFunctionBeforeFrameFinalized(), restoreCalleeSavedRegisters(), restoreWin32EHStackPointers(), and spillCalleeSavedRegisters().

◆ TII

const X86InstrInfo& llvm::X86FrameLowering::TII

Definition at line 34 of file X86FrameLowering.h.

Referenced by adjustForHiPEPrologue(), adjustForSegmentedStacks(), BuildCFI(), calculateSetFPREG(), eliminateCallFramePseudoInstr(), emitEpilogue(), emitPrologue(), emitSPUpdate(), inlineStackProbe(), processFunctionBeforeFrameFinalized(), restoreCalleeSavedRegisters(), restoreWin32EHStackPointers(), and spillCalleeSavedRegisters().

◆ TRI

const X86RegisterInfo* llvm::X86FrameLowering::TRI

Definition at line 35 of file X86FrameLowering.h.

Referenced by adjustForHiPEPrologue(), canSimplifyCallFramePseudos(), canUseAsPrologue(), determineCalleeSaves(), emitEpilogue(), emitPrologue(), emitSPUpdate(), getFrameIndexReference(), getFrameIndexReferencePreferSP(), getFrameIndexReferenceSP(), getInitialCFAOffset(), getInitialCFARegister(), hasFP(), isFuncletReturnInstr(), orderFrameObjects(), restoreWin32EHStackPointers(), and X86FrameLowering().

◆ Uses64BitFramePtr

bool llvm::X86FrameLowering::Uses64BitFramePtr

True if the 64-bit frame or stack pointer should be used.

True for most 64-bit targets with the exception of x32. If this is false, 32-bit instruction operands should be used to manipulate StackPtr and FramePtr.

Definition at line 47 of file X86FrameLowering.h.

Referenced by calculateSetFPREG(), emitEpilogue(), emitPrologue(), emitSPUpdate(), llvm::X86RegisterInfo::getPointerRegClass(), restoreWin32EHStackPointers(), and X86FrameLowering().

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

lib/Target/X86/X86FrameLowering.h
lib/Target/X86/X86FrameLowering.cpp

Public Member Functions

Public Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ X86FrameLowering()

Member Function Documentation

◆ adjustForHiPEPrologue()

◆ adjustForSegmentedStacks()

◆ assignCalleeSavedSpillSlots()

◆ BuildCFI()

◆ canSimplifyCallFramePseudos()

◆ canUseAsEpilogue()

◆ canUseAsPrologue()

◆ canUseLEAForSPInEpilogue()

◆ determineCalleeSaves()

◆ eliminateCallFramePseudoInstr()

◆ emitCalleeSavedFrameMoves()

◆ emitEpilogue()

◆ emitPrologue()

◆ emitSPUpdate()

◆ emitStackProbe()

◆ enableShrinkWrapping()

◆ getFrameIndexReference()

◆ getFrameIndexReferencePreferSP()

◆ getFrameIndexReferenceSP()

◆ getInitialCFAOffset()

◆ getInitialCFARegister()

◆ getWinEHParentFrameOffset()

◆ hasFP()

◆ hasReservedCallFrame()

◆ inlineStackProbe()

◆ mergeSPUpdates()

◆ needsFrameIndexResolution()

◆ orderFrameObjects()

◆ processFunctionBeforeFrameFinalized()

◆ restoreCalleeSavedRegisters()

◆ restoreWin32EHStackPointers()

◆ spillCalleeSavedRegisters()

Member Data Documentation

◆ Is64Bit

◆ IsLP64

◆ SlotSize

◆ StackPtr

◆ STI

◆ TII

◆ TRI

◆ Uses64BitFramePtr