llvm::CoalescerPair Class Reference

#include <RegisterCoalescer.h>

Public Member Functions
	CoalescerPair (const TargetRegisterInfo &tri)
	CoalescerPair (unsigned VirtReg, unsigned PhysReg, const TargetRegisterInfo &tri)
bool	setRegisters (const MachineInstr *)
bool	flip ()
bool	isCoalescable (const MachineInstr *) const
bool	isPhys () const
	isPhys - Return true if DstReg is a physical register. More...
bool	isPartial () const
bool	isCrossClass () const
bool	isFlipped () const
unsigned	getDstReg () const
unsigned	getSrcReg () const
	getSrcReg - Return the virtual register that will be coalesced away. More...
unsigned	getDstIdx () const
unsigned	getSrcIdx () const
const TargetRegisterClass *	getNewRC () const
	getNewRC - Return the register class of the coalesced register. More...

Detailed Description

CoalescerPair - A helper class for register coalescers. When deciding if two registers can be coalesced, CoalescerPair can determine if a copy instruction would become an identity copy after coalescing.

Definition at line 28 of file RegisterCoalescer.h.

Constructor & Destructor Documentation

llvm::CoalescerPair::CoalescerPair ( const TargetRegisterInfo &  tri )

inline

Definition at line 62 of file RegisterCoalescer.h.

llvm::CoalescerPair::CoalescerPair ( unsigned  VirtReg, unsigned  PhysReg, const TargetRegisterInfo &  tri  )

inline

Create a CoalescerPair representing a virtreg-to-physreg copy. No need to call setRegisters().

Definition at line 68 of file RegisterCoalescer.h.

Member Function Documentation

bool CoalescerPair::flip

(

)

flip - Swap SrcReg and DstReg. Return false if swapping is impossible because DstReg is a physical register, or SubIdx is set.

Definition at line 341 of file RegisterCoalescer.cpp.

References llvm::TargetRegisterInfo::isPhysicalRegister(), and std::swap().

unsigned llvm::CoalescerPair::getDstIdx ( ) const

inline

getDstIdx - Return the subregister index that DstReg will be coalesced into, or 0.

Definition at line 109 of file RegisterCoalescer.h.

unsigned llvm::CoalescerPair::getDstReg ( ) const

inline

getDstReg - Return the register (virtual or physical) that will remain after coalescing.

Definition at line 102 of file RegisterCoalescer.h.

const TargetRegisterClass* llvm::CoalescerPair::getNewRC ( ) const

inline

getNewRC - Return the register class of the coalesced register.

Definition at line 116 of file RegisterCoalescer.h.

unsigned llvm::CoalescerPair::getSrcIdx ( ) const

inline

getSrcIdx - Return the subregister index that SrcReg will be coalesced into, or 0.

Definition at line 113 of file RegisterCoalescer.h.

unsigned llvm::CoalescerPair::getSrcReg ( ) const

inline

getSrcReg - Return the virtual register that will be coalesced away.

Definition at line 105 of file RegisterCoalescer.h.

bool CoalescerPair::isCoalescable

(

const MachineInstr *

MI

)

const

isCoalescable - Return true if MI is a copy instruction that will become an identity copy after coalescing.

Definition at line 350 of file RegisterCoalescer.cpp.

References llvm::TargetRegisterInfo::composeSubRegIndices(), llvm::MCRegisterInfo::getSubReg(), isMoveInstr(), llvm::TargetRegisterInfo::isPhysicalRegister(), and std::swap().

Referenced by llvm::LiveRange::overlaps().

bool llvm::CoalescerPair::isCrossClass ( ) const

inline

isCrossClass - Return true if DstReg is virtual and NewRC is a smaller register class than DstReg's.

Definition at line 94 of file RegisterCoalescer.h.

bool llvm::CoalescerPair::isFlipped ( ) const

inline

isFlipped - Return true when getSrcReg is the register being defined by the original copy instruction.

Definition at line 98 of file RegisterCoalescer.h.

bool llvm::CoalescerPair::isPartial ( ) const

inline

isPartial - Return true if the original copy instruction did not copy the full register, but was a subreg operation.

Definition at line 90 of file RegisterCoalescer.h.

bool llvm::CoalescerPair::isPhys ( ) const

inline

isPhys - Return true if DstReg is a physical register.

Definition at line 86 of file RegisterCoalescer.h.

bool CoalescerPair::setRegisters

(

const MachineInstr *

MI

)

setRegisters - set registers to match the copy instruction MI. Return false if MI is not a coalescable copy instruction.

Definition at line 252 of file RegisterCoalescer.cpp.

References llvm::TargetRegisterClass::contains(), llvm::TargetRegisterInfo::getCommonSubClass(), llvm::TargetRegisterInfo::getCommonSuperRegClass(), llvm::TargetRegisterInfo::getMatchingSuperReg(), llvm::TargetRegisterInfo::getMatchingSuperRegClass(), llvm::MachineInstr::getParent(), llvm::MachineBasicBlock::getParent(), llvm::MachineRegisterInfo::getRegClass(), llvm::MachineFunction::getRegInfo(), llvm::MCRegisterInfo::getSubReg(), isMoveInstr(), llvm::TargetRegisterInfo::isPhysicalRegister(), llvm::TargetRegisterInfo::isVirtualRegister(), MRI, and std::swap().

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

• RegisterCoalescer.h
• RegisterCoalescer.cpp