#include "llvm/CodeGen/LiveRangeEdit.h"

Inheritance diagram for llvm::LiveRangeEdit:

Classes
class	Delegate
	Callback methods for LiveRangeEdit owners. More...

struct	Remat
	Remat - Information needed to rematerialize at a specific location. More...

Public Types
using	iterator = SmallVectorImpl< Register >::const_iterator
	Iterator for accessing the new registers added by this edit.

Public Member Functions
	LiveRangeEdit (const LiveInterval parent, SmallVectorImpl< Register > &newRegs, MachineFunction &MF, LiveIntervals &lis, VirtRegMap vrm, Delegate delegate=nullptr, SmallPtrSet< MachineInstr , 32 > *deadRemats=nullptr)
	Create a LiveRangeEdit for breaking down parent into smaller pieces.

	~LiveRangeEdit () override

const LiveInterval &	getParent () const

Register	getReg () const

iterator	begin () const

iterator	end () const

unsigned	size () const

bool	empty () const

Register	get (unsigned idx) const

void	pop_back ()
	pop_back - It allows LiveRangeEdit users to drop new registers.

ArrayRef< Register >	regs () const

Register	createFrom (Register OldReg)
	createFrom - Create a new virtual register based on OldReg.

LiveInterval &	createEmptyInterval ()
	create - Create a new register with the same class and original slot as parent.

Register	create ()

bool	anyRematerializable ()
	anyRematerializable - Return true if any parent values may be rematerializable.

bool	checkRematerializable (VNInfo VNI, const MachineInstr DefMI)
	checkRematerializable - Manually add VNI to the list of rematerializable values if DefMI may be rematerializable.

bool	allUsesAvailableAt (const MachineInstr *OrigMI, SlotIndex OrigIdx, SlotIndex UseIdx) const
	allUsesAvailableAt - Return true if all registers used by OrigMI at OrigIdx are also available with the same value at UseIdx.

bool	canRematerializeAt (Remat &RM, VNInfo *OrigVNI, SlotIndex UseIdx, bool cheapAsAMove)
	canRematerializeAt - Determine if ParentVNI can be rematerialized at UseIdx.

SlotIndex	rematerializeAt (MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, Register DestReg, const Remat &RM, const TargetRegisterInfo &, bool Late=false, unsigned SubIdx=0, MachineInstr *ReplaceIndexMI=nullptr)
	rematerializeAt - Rematerialize RM.ParentVNI into DestReg by inserting an instruction into MBB before MI.

void	markRematerialized (const VNInfo *ParentVNI)
	markRematerialized - explicitly mark a value as rematerialized after doing it manually.

bool	didRematerialize (const VNInfo *ParentVNI) const
	didRematerialize - Return true if ParentVNI was rematerialized anywhere.

void	eraseVirtReg (Register Reg)
	eraseVirtReg - Notify the delegate that Reg is no longer in use, and try to erase it from LIS.

void	eliminateDeadDefs (SmallVectorImpl< MachineInstr * > &Dead, ArrayRef< Register > RegsBeingSpilled=std::nullopt)
	eliminateDeadDefs - Try to delete machine instructions that are now dead (allDefsAreDead returns true).

void	calculateRegClassAndHint (MachineFunction &, VirtRegAuxInfo &)
	calculateRegClassAndHint - Recompute register class and hint for each new register.

Detailed Description

Definition at line 42 of file LiveRangeEdit.h.

Member Typedef Documentation

◆ iterator

using llvm::LiveRangeEdit::iterator = SmallVectorImpl<Register>::const_iterator

Iterator for accessing the new registers added by this edit.

Definition at line 148 of file LiveRangeEdit.h.

Constructor & Destructor Documentation

◆ LiveRangeEdit()

llvm::LiveRangeEdit::LiveRangeEdit	(	const LiveInterval *	parent,
		SmallVectorImpl< Register > &	newRegs,
		MachineFunction &	MF,
		LiveIntervals &	lis,
		VirtRegMap *	vrm,
		Delegate *	delegate = `nullptr`,
		SmallPtrSet< MachineInstr , 32 >	deadRemats = `nullptr`
	)

inline

Create a LiveRangeEdit for breaking down parent into smaller pieces.

Parameters

parent	The register being spilled or split.
newRegs	List to receive any new registers created. This needn't be empty initially, any existing registers are ignored.
MF	The MachineFunction the live range edit is taking place in.
lis	The collection of all live intervals in this function.
vrm	Map of virtual registers to physical registers for this function. If NULL, no virtual register map updates will be done. This could be the case if called before Regalloc.
deadRemats	The collection of all the instructions defining an original reg and are dead after remat.

Definition at line 128 of file LiveRangeEdit.h.

References MRI, and TII.

◆ ~LiveRangeEdit()

llvm::LiveRangeEdit::~LiveRangeEdit ( )

inlineoverride

Definition at line 138 of file LiveRangeEdit.h.

References MRI.

Member Function Documentation

◆ allUsesAvailableAt()

bool LiveRangeEdit::allUsesAvailableAt	(	const MachineInstr *	OrigMI,
		SlotIndex	OrigIdx,
		SlotIndex	UseIdx
	)		const

allUsesAvailableAt - Return true if all registers used by OrigMI at OrigIdx are also available with the same value at UseIdx.

Definition at line 106 of file LiveRangeEdit.cpp.

References llvm::LiveIntervals::getInterval(), llvm::MachineRegisterInfo::getMaxLaneMaskForVReg(), llvm::SlotIndex::getRegSlot(), llvm::MachineRegisterInfo::getTargetRegisterInfo(), llvm::LiveRange::getVNInfoAt(), llvm::LiveInterval::hasSubRanges(), llvm::MachineRegisterInfo::isConstantPhysReg(), llvm::TargetInstrInfo::isIgnorableUse(), llvm::SlotIndex::isSameInstr(), llvm::LaneBitmask::none(), llvm::MachineInstr::operands(), llvm::LiveInterval::subranges(), SubReg, and TRI.

Referenced by canRematerializeAt().

◆ anyRematerializable()

bool LiveRangeEdit::anyRematerializable ( )

anyRematerializable - Return true if any parent values may be rematerializable.

This function must be called before any rematerialization is attempted.

Definition at line 98 of file LiveRangeEdit.cpp.

Referenced by llvm::SplitEditor::reset().

◆ begin()

iterator llvm::LiveRangeEdit::begin ( ) const

inline

Definition at line 149 of file LiveRangeEdit.h.

References llvm::SmallVectorTemplateCommon< T, typename >::begin().

◆ calculateRegClassAndHint()

void LiveRangeEdit::calculateRegClassAndHint	(	MachineFunction &	MF,
		VirtRegAuxInfo &	VRAI
	)

calculateRegClassAndHint - Recompute register class and hint for each new register.

Definition at line 496 of file LiveRangeEdit.cpp.

References llvm::VirtRegAuxInfo::calculateSpillWeightAndHint(), llvm::dbgs(), get(), llvm::LiveIntervals::getInterval(), llvm::MachineRegisterInfo::getRegClass(), llvm::MachineFunction::getSubtarget(), I, LLVM_DEBUG, llvm::printReg(), llvm::MachineRegisterInfo::recomputeRegClass(), llvm::LiveInterval::reg(), size(), Size, and TRI.

◆ canRematerializeAt()

bool LiveRangeEdit::canRematerializeAt	(	Remat &	RM,
		VNInfo *	OrigVNI,
		SlotIndex	UseIdx,
		bool	cheapAsAMove
	)

canRematerializeAt - Determine if ParentVNI can be rematerialized at UseIdx.

It is assumed that parent_.getVNINfoAt(UseIdx) == ParentVNI. When cheapAsAMove is set, only cheap remats are allowed.

Definition at line 158 of file LiveRangeEdit.cpp.

References allUsesAvailableAt(), assert(), llvm::LiveIntervals::getInstructionIndex(), and llvm::TargetInstrInfo::isAsCheapAsAMove().

◆ checkRematerializable()

bool LiveRangeEdit::checkRematerializable	(	VNInfo *	VNI,
		const MachineInstr *	DefMI
	)

checkRematerializable - Manually add VNI to the list of rematerializable values if DefMI may be rematerializable.

Definition at line 71 of file LiveRangeEdit.cpp.

References assert(), DefMI, and llvm::TargetInstrInfo::isTriviallyReMaterializable().

◆ create()

Register llvm::LiveRangeEdit::create ( )

inline

Definition at line 176 of file LiveRangeEdit.h.

References createFrom(), and getReg().

◆ createEmptyInterval()

LiveInterval & llvm::LiveRangeEdit::createEmptyInterval ( )

inline

create - Create a new register with the same class and original slot as parent.

Definition at line 172 of file LiveRangeEdit.h.

References getReg().

Referenced by llvm::SplitEditor::openIntv().

◆ createFrom()

Register LiveRangeEdit::createFrom ( Register OldReg )

createFrom - Create a new virtual register based on OldReg.

Definition at line 55 of file LiveRangeEdit.cpp.

References llvm::MachineRegisterInfo::cloneVirtualRegister(), llvm::LiveIntervals::getInterval(), llvm::VirtRegMap::getOriginal(), llvm::LiveInterval::isSpillable(), llvm::LiveInterval::markNotSpillable(), and llvm::VirtRegMap::setIsSplitFromReg().

Referenced by create().

◆ didRematerialize()

bool llvm::LiveRangeEdit::didRematerialize ( const VNInfo * ParentVNI ) const

inline

didRematerialize - Return true if ParentVNI was rematerialized anywhere.

Definition at line 225 of file LiveRangeEdit.h.

References llvm::SmallPtrSetImpl< PtrType >::count().

◆ eliminateDeadDefs()

void LiveRangeEdit::eliminateDeadDefs	(	SmallVectorImpl< MachineInstr * > &	Dead,
		ArrayRef< Register >	RegsBeingSpilled = `std::nullopt`
	)

eliminateDeadDefs - Try to delete machine instructions that are now dead (allDefsAreDead returns true).

This may cause live intervals to be trimmed and further dead efs to be eliminated. RegsBeingSpilled lists registers currently being spilled by the register allocator. These registers should not be split into new intervals as currently those new intervals are not guaranteed to spill.

Definition at line 437 of file LiveRangeEdit.cpp.

References llvm::SetVector< T, Vector, Set, N >::empty(), llvm::SmallVectorBase< Size_T >::empty(), llvm::VirtRegMap::getOriginal(), llvm::is_contained(), llvm::LiveRangeEdit::Delegate::LRE_DidCloneVirtReg(), llvm::LiveRangeEdit::Delegate::LRE_WillShrinkVirtReg(), llvm::SetVector< T, Vector, Set, N >::pop_back_val(), llvm::LiveInterval::reg(), llvm::LiveRange::RenumberValues(), llvm::VirtRegMap::setIsSplitFromReg(), llvm::LiveIntervals::shrinkToUses(), and llvm::LiveIntervals::splitSeparateComponents().

◆ empty()

bool llvm::LiveRangeEdit::empty ( ) const

inline

Definition at line 152 of file LiveRangeEdit.h.

References size().

Referenced by llvm::SplitEditor::openIntv().

◆ end()

iterator llvm::LiveRangeEdit::end ( ) const

inline

Definition at line 150 of file LiveRangeEdit.h.

References llvm::SmallVectorTemplateCommon< T, typename >::end().

◆ eraseVirtReg()

void LiveRangeEdit::eraseVirtReg ( Register Reg )

eraseVirtReg - Notify the delegate that Reg is no longer in use, and try to erase it from LIS.

Definition at line 202 of file LiveRangeEdit.cpp.

References llvm::LiveRangeEdit::Delegate::LRE_CanEraseVirtReg(), and llvm::LiveIntervals::removeInterval().

◆ get()

Register llvm::LiveRangeEdit::get ( unsigned idx ) const

inline

Definition at line 153 of file LiveRangeEdit.h.

Referenced by calculateRegClassAndHint(), and llvm::SplitEditor::leaveIntvAtTop().

◆ getParent()

const LiveInterval & llvm::LiveRangeEdit::getParent ( ) const

inline

Definition at line 140 of file LiveRangeEdit.h.

References assert().

Referenced by llvm::SplitEditor::enterIntvAfter(), llvm::SplitEditor::enterIntvAtEnd(), llvm::SplitEditor::enterIntvBefore(), getReg(), llvm::SplitEditor::leaveIntvAfter(), llvm::SplitEditor::leaveIntvAtTop(), llvm::SplitEditor::leaveIntvBefore(), and llvm::SplitEditor::overlapIntv().

◆ getReg()

Register llvm::LiveRangeEdit::getReg ( ) const

inline

Definition at line 145 of file LiveRangeEdit.h.

References getParent(), and llvm::LiveInterval::reg().

Referenced by create(), createEmptyInterval(), llvm::SplitEditor::leaveIntvAfter(), and llvm::SplitEditor::overlapIntv().

◆ markRematerialized()

void llvm::LiveRangeEdit::markRematerialized ( const VNInfo * ParentVNI )

inline

markRematerialized - explicitly mark a value as rematerialized after doing it manually.

Definition at line 220 of file LiveRangeEdit.h.

References llvm::SmallPtrSetImpl< PtrType >::insert().

◆ pop_back()

void llvm::LiveRangeEdit::pop_back ( )

inline

pop_back - It allows LiveRangeEdit users to drop new registers.

The context is when an original def instruction of a register is dead after rematerialization, we still want to keep it for following rematerializations. We save the def instruction in DeadRemats, and replace the original dst register with a new dummy register so the live range of original dst register can be shrinked normally. We don't want to allocate phys register for the dummy register, so we want to drop it from the NewRegs set.

Definition at line 163 of file LiveRangeEdit.h.

References llvm::SmallVectorTemplateBase< T, bool >::pop_back().

◆ regs()

ArrayRef< Register > llvm::LiveRangeEdit::regs ( ) const

inline

Definition at line 165 of file LiveRangeEdit.h.

References llvm::ArrayRef< T >::slice().

◆ rematerializeAt()

SlotIndex LiveRangeEdit::rematerializeAt	(	MachineBasicBlock &	MBB,
		MachineBasicBlock::iterator	MI,
		Register	DestReg,
		const Remat &	RM,
		const TargetRegisterInfo &	tri,
		bool	Late = `false`,
		unsigned	SubIdx = `0`,
		MachineInstr *	ReplaceIndexMI = `nullptr`
	)

rematerializeAt - Rematerialize RM.ParentVNI into DestReg by inserting an instruction into MBB before MI.

The new instruction is mapped, but liveness is not updated. If ReplaceIndexMI is not null it will be replaced by new MI in the index map. Return the SlotIndex of the new instruction.

Definition at line 182 of file LiveRangeEdit.cpp.

References assert(), llvm::SlotIndex::getRegSlot(), llvm::LiveIntervals::getSlotIndexes(), llvm::SlotIndexes::insertMachineInstrInMaps(), MBB, MI, llvm::TargetInstrInfo::reMaterialize(), and llvm::LiveIntervals::ReplaceMachineInstrInMaps().

◆ size()

unsigned llvm::LiveRangeEdit::size ( ) const

inline

Definition at line 151 of file LiveRangeEdit.h.

References llvm::SmallVectorBase< Size_T >::size().

Referenced by calculateRegClassAndHint(), empty(), and llvm::SplitEditor::openIntv().

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

include/llvm/CodeGen/LiveRangeEdit.h
lib/CodeGen/LiveRangeEdit.cpp

Classes

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ iterator

Constructor & Destructor Documentation

◆ LiveRangeEdit()

◆ ~LiveRangeEdit()

Member Function Documentation

◆ allUsesAvailableAt()

◆ anyRematerializable()

◆ begin()

◆ calculateRegClassAndHint()

◆ canRematerializeAt()

◆ checkRematerializable()

◆ create()

◆ createEmptyInterval()

◆ createFrom()

◆ didRematerialize()

◆ eliminateDeadDefs()

◆ empty()

◆ end()

◆ eraseVirtReg()

◆ get()

◆ getParent()

◆ getReg()

◆ markRematerialized()

◆ pop_back()

◆ regs()

◆ rematerializeAt()

◆ size()