#include "llvm/CodeGen/LiveVariables.h"

Classes
struct	VarInfo
	VarInfo - This represents the regions where a virtual register is live in the program. More...

Public Member Functions
LLVM_ABI	LiveVariables (MachineFunction &MF)
LLVM_ABI void	print (raw_ostream &OS) const
LLVM_ABI void	recomputeForSingleDefVirtReg (Register Reg)
	Recompute liveness from scratch for a virtual register `Reg` that is known to have a single def that dominates all uses.
LLVM_ABI void	replaceKillInstruction (Register Reg, MachineInstr &OldMI, MachineInstr &NewMI)
	replaceKillInstruction - Update register kill info by replacing a kill instruction with a new one.
void	addVirtualRegisterKilled (Register IncomingReg, MachineInstr &MI, bool AddIfNotFound=false)
	addVirtualRegisterKilled - Add information about the fact that the specified register is killed after being used by the specified instruction.
bool	removeVirtualRegisterKilled (Register Reg, MachineInstr &MI)
	removeVirtualRegisterKilled - Remove the specified kill of the virtual register from the live variable information.
LLVM_ABI void	removeVirtualRegistersKilled (MachineInstr &MI)
	removeVirtualRegistersKilled - Remove all killed info for the specified instruction.
void	addVirtualRegisterDead (Register IncomingReg, MachineInstr &MI, bool AddIfNotFound=false)
	addVirtualRegisterDead - Add information about the fact that the specified register is dead after being used by the specified instruction.
bool	removeVirtualRegisterDead (Register Reg, MachineInstr &MI)
	removeVirtualRegisterDead - Remove the specified kill of the virtual register from the live variable information.
LLVM_ABI VarInfo &	getVarInfo (Register Reg)
	getVarInfo - Return the VarInfo structure for the specified VIRTUAL register.
LLVM_ABI void	MarkVirtRegAliveInBlock (VarInfo &VRInfo, MachineBasicBlock DefBlock, MachineBasicBlock BB)
LLVM_ABI void	MarkVirtRegAliveInBlock (VarInfo &VRInfo, MachineBasicBlock DefBlock, MachineBasicBlock BB, SmallVectorImpl< MachineBasicBlock * > &WorkList)
LLVM_ABI void	HandleVirtRegDef (Register reg, MachineInstr &MI)
LLVM_ABI void	HandleVirtRegUse (Register reg, MachineBasicBlock *MBB, MachineInstr &MI)
bool	isLiveIn (Register Reg, const MachineBasicBlock &MBB)
LLVM_ABI bool	isLiveOut (Register Reg, const MachineBasicBlock &MBB)
	isLiveOut - Determine if Reg is live out from MBB, when not considering PHI nodes.
LLVM_ABI void	addNewBlock (MachineBasicBlock BB, MachineBasicBlock DomBB, MachineBasicBlock *SuccBB)
	addNewBlock - Add a new basic block BB between DomBB and SuccBB.
LLVM_ABI void	addNewBlock (MachineBasicBlock BB, MachineBasicBlock DomBB, MachineBasicBlock *SuccBB, std::vector< SparseBitVector<> > &LiveInSets)
	addNewBlock - Add a new basic block BB as an empty succcessor to DomBB.

Friends
class	LiveVariablesWrapperPass

Detailed Description

Definition at line 49 of file LiveVariables.h.

Constructor & Destructor Documentation

◆ LiveVariables()

LiveVariables::LiveVariables ( MachineFunction & MF )

Definition at line 73 of file LiveVariables.cpp.

Member Function Documentation

◆ addNewBlock() [1/2]

void LiveVariables::addNewBlock	(	MachineBasicBlock *	BB,
		MachineBasicBlock *	DomBB,
		MachineBasicBlock *	SuccBB )

addNewBlock - Add a new basic block BB between DomBB and SuccBB.

addNewBlock - Add a new basic block BB as an empty succcessor to DomBB.

All variables that are live out of DomBB and live into SuccBB will be marked as passing live through BB. This method assumes that the machine code is still in SSA form.

All variables that are live out of DomBB will be marked as passing live through BB.

Definition at line 814 of file LiveVariables.cpp.

References llvm::LiveVariables::VarInfo::AliveBlocks, llvm::MachineBasicBlock::begin(), llvm::detail::DenseSetImpl< ValueT, MapTy, ValueInfoT >::count(), llvm::MachineBasicBlock::end(), llvm::MachineBasicBlock::getNumber(), getVarInfo(), llvm::Register::index2VirtReg(), llvm::detail::DenseSetImpl< ValueT, MapTy, ValueInfoT >::insert(), and llvm::SparseBitVector< ElementSize >::set().

◆ addNewBlock() [2/2]

void LiveVariables::addNewBlock	(	MachineBasicBlock *	BB,
		MachineBasicBlock *	DomBB,
		MachineBasicBlock *	SuccBB,
		std::vector< SparseBitVector<> > &	LiveInSets )

addNewBlock - Add a new basic block BB as an empty succcessor to DomBB.

All variables that are live out of DomBB will be marked as passing live through BB. LiveInSets[BB] is not updated (because it is not needed during PHIElimination).

Definition at line 864 of file LiveVariables.cpp.

References llvm::LiveVariables::VarInfo::AliveBlocks, llvm::MachineBasicBlock::begin(), llvm::MachineBasicBlock::end(), llvm::MachineBasicBlock::getNumber(), getVarInfo(), llvm::Register::index2VirtReg(), and llvm::SparseBitVector< ElementSize >::set().

◆ addVirtualRegisterDead()

void llvm::LiveVariables::addVirtualRegisterDead	(	Register	IncomingReg,
		MachineInstr &	MI,
		bool	AddIfNotFound = false )

inline

addVirtualRegisterDead - Add information about the fact that the specified register is dead after being used by the specified instruction.

If AddIfNotFound is true, add a implicit operand if it's not found.

Definition at line 240 of file LiveVariables.h.

References getVarInfo(), llvm::LiveVariables::VarInfo::Kills, and MI.

◆ addVirtualRegisterKilled()

void llvm::LiveVariables::addVirtualRegisterKilled	(	Register	IncomingReg,
		MachineInstr &	MI,
		bool	AddIfNotFound = false )

inline

addVirtualRegisterKilled - Add information about the fact that the specified register is killed after being used by the specified instruction.

If AddIfNotFound is true, add a implicit operand if it's not found.

Definition at line 205 of file LiveVariables.h.

References getVarInfo(), llvm::LiveVariables::VarInfo::Kills, and MI.

◆ getVarInfo()

LiveVariables::VarInfo & LiveVariables::getVarInfo ( Register Reg )

getVarInfo - Return the VarInfo structure for the specified VIRTUAL register.

getVarInfo - Get (possibly creating) a VarInfo object for the given vreg.

Definition at line 113 of file LiveVariables.cpp.

References assert().

Referenced by addNewBlock(), addNewBlock(), addVirtualRegisterDead(), addVirtualRegisterKilled(), llvm::SIInstrInfo::convertToThreeAddress(), llvm::X86InstrInfo::convertToThreeAddress(), HandleVirtRegDef(), HandleVirtRegUse(), isLiveIn(), isLiveOut(), recomputeForSingleDefVirtReg(), removeVirtualRegisterDead(), removeVirtualRegisterKilled(), removeVirtualRegistersKilled(), and replaceKillInstruction().

◆ HandleVirtRegDef()

void LiveVariables::HandleVirtRegDef	(	Register	reg,
		MachineInstr &	MI )

Definition at line 207 of file LiveVariables.cpp.

References llvm::LiveVariables::VarInfo::AliveBlocks, llvm::SparseBitVector< ElementSize >::empty(), getVarInfo(), llvm::LiveVariables::VarInfo::Kills, and MI.

◆ HandleVirtRegUse()

void LiveVariables::HandleVirtRegUse	(	Register	reg,
		MachineBasicBlock *	MBB,
		MachineInstr &	MI )

Definition at line 156 of file LiveVariables.cpp.

References llvm::LiveVariables::VarInfo::AliveBlocks, assert(), getVarInfo(), llvm::LiveVariables::VarInfo::Kills, MarkVirtRegAliveInBlock(), MBB, MI, and llvm::SparseBitVector< ElementSize >::test().

◆ isLiveIn()

bool llvm::LiveVariables::isLiveIn	(	Register	Reg,
		const MachineBasicBlock &	MBB )

inline

Definition at line 283 of file LiveVariables.h.

References getVarInfo(), llvm::LiveVariables::VarInfo::isLiveIn(), MBB, and Reg.

◆ isLiveOut()

bool LiveVariables::isLiveOut	(	Register	Reg,
		const MachineBasicBlock &	MBB )

isLiveOut - Determine if Reg is live out from MBB, when not considering PHI nodes.

This means that Reg is either killed by a successor block or passed through one.

Definition at line 789 of file LiveVariables.cpp.

References llvm::SmallPtrSetImpl< PtrType >::count(), getVarInfo(), llvm::SmallPtrSetImpl< PtrType >::insert(), MBB, and MI.

◆ MarkVirtRegAliveInBlock() [1/2]

void LiveVariables::MarkVirtRegAliveInBlock	(	VarInfo &	VRInfo,
		MachineBasicBlock *	DefBlock,
		MachineBasicBlock *	BB )

Definition at line 144 of file LiveVariables.cpp.

References llvm::SmallVectorTemplateCommon< T, typename >::empty(), MarkVirtRegAliveInBlock(), MBB, and llvm::SmallVectorImpl< T >::pop_back_val().

Referenced by HandleVirtRegUse(), and MarkVirtRegAliveInBlock().

◆ MarkVirtRegAliveInBlock() [2/2]

void LiveVariables::MarkVirtRegAliveInBlock	(	VarInfo &	VRInfo,
		MachineBasicBlock *	DefBlock,
		MachineBasicBlock *	BB,
		SmallVectorImpl< MachineBasicBlock * > &	WorkList )

Definition at line 119 of file LiveVariables.cpp.

References llvm::LiveVariables::VarInfo::AliveBlocks, assert(), llvm::SmallVectorTemplateCommon< T, typename >::end(), llvm::SmallVectorImpl< T >::insert(), llvm::LiveVariables::VarInfo::Kills, MBB, llvm::SparseBitVector< ElementSize >::set(), and llvm::SparseBitVector< ElementSize >::test().

◆ print()

void LiveVariables::print ( raw_ostream & OS ) const

Definition at line 78 of file LiveVariables.cpp.

References I, and llvm::Register::index2VirtReg().

Referenced by llvm::LiveVariables::VarInfo::dump().

◆ recomputeForSingleDefVirtReg()

void LiveVariables::recomputeForSingleDefVirtReg ( Register Reg )

Recompute liveness from scratch for a virtual register Reg that is known to have a single def that dominates all uses.

This can be useful after removing some uses of Reg. It is not necessary for the whole machine function to be in SSA form.

Definition at line 648 of file LiveVariables.cpp.

References llvm::SmallVectorImpl< T >::append(), assert(), DefMI, llvm::SmallVectorTemplateCommon< T, typename >::empty(), llvm::MachineBasicBlock::getNumber(), getVarInfo(), MI, llvm::SmallVectorImpl< T >::pop_back_val(), llvm::MachineBasicBlock::pred_begin(), llvm::MachineBasicBlock::pred_end(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::reverse(), llvm::SparseBitVector< ElementSize >::set(), and UseMI.

Referenced by llvm::PPCInstrInfo::promoteInstr32To64ForElimEXTSW().

◆ removeVirtualRegisterDead()

bool llvm::LiveVariables::removeVirtualRegisterDead	(	Register	Reg,
		MachineInstr &	MI )

inline

removeVirtualRegisterDead - Remove the specified kill of the virtual register from the live variable information.

Returns true if the variable was marked dead at the specified instruction, false otherwise.

Definition at line 250 of file LiveVariables.h.

References assert(), getVarInfo(), MI, and Reg.

◆ removeVirtualRegisterKilled()

bool llvm::LiveVariables::removeVirtualRegisterKilled	(	Register	Reg,
		MachineInstr &	MI )

inline

removeVirtualRegisterKilled - Remove the specified kill of the virtual register from the live variable information.

Returns true if the variable was marked as killed by the specified instruction, false otherwise.

Definition at line 215 of file LiveVariables.h.

References assert(), getVarInfo(), MI, and Reg.

◆ removeVirtualRegistersKilled()

void LiveVariables::removeVirtualRegistersKilled ( MachineInstr & MI )

removeVirtualRegistersKilled - Remove all killed info for the specified instruction.

Definition at line 742 of file LiveVariables.cpp.

References assert(), llvm::MachineOperand::getReg(), getVarInfo(), llvm::MachineOperand::isKill(), llvm::MachineOperand::isReg(), MI, llvm::LiveVariables::VarInfo::removeKill(), and llvm::MachineOperand::setIsKill().

◆ replaceKillInstruction()

void LiveVariables::replaceKillInstruction	(	Register	Reg,
		MachineInstr &	OldMI,
		MachineInstr &	NewMI )

replaceKillInstruction - Update register kill info by replacing a kill instruction with a new one.

Definition at line 734 of file LiveVariables.cpp.

References getVarInfo(), and llvm::replace().

Referenced by llvm::X86InstrInfo::classifyLEAReg(), llvm::RISCVInstrInfo::convertToThreeAddress(), llvm::SystemZInstrInfo::convertToThreeAddress(), llvm::X86InstrInfo::convertToThreeAddress(), and updateLiveVariables().

◆ LiveVariablesWrapperPass

friend class LiveVariablesWrapperPass

friend

Definition at line 50 of file LiveVariables.h.

References LiveVariablesWrapperPass.

Referenced by LiveVariablesWrapperPass.

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

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

Classes

Public Member Functions

Friends

Detailed Description

Constructor & Destructor Documentation

◆ LiveVariables()

Member Function Documentation

◆ addNewBlock() [1/2]

◆ addNewBlock() [2/2]

◆ addVirtualRegisterDead()

◆ addVirtualRegisterKilled()

◆ getVarInfo()

◆ HandleVirtRegDef()

◆ HandleVirtRegUse()

◆ isLiveIn()

◆ isLiveOut()

◆ MarkVirtRegAliveInBlock() [1/2]

◆ MarkVirtRegAliveInBlock() [2/2]

◆ print()

◆ recomputeForSingleDefVirtReg()

◆ removeVirtualRegisterDead()

◆ removeVirtualRegisterKilled()

◆ removeVirtualRegistersKilled()

◆ replaceKillInstruction()

Friends And Related Symbol Documentation

◆ LiveVariablesWrapperPass