class CoalescerPair

Declaration

class CoalescerPair { /* full declaration omitted */ };

Description

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.

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:26

Method Overview

• public CoalescerPair(const llvm::TargetRegisterInfo & tri)
• public CoalescerPair(unsigned int VirtReg, unsigned int PhysReg, const llvm::TargetRegisterInfo & tri)
• public bool flip()
• public unsigned int getDstIdx() const
• public unsigned int getDstReg() const
• public const llvm::TargetRegisterClass * getNewRC() const
• public unsigned int getSrcIdx() const
• public unsigned int getSrcReg() const
• public bool isCoalescable(const llvm::MachineInstr *) const
• public bool isCrossClass() const
• public bool isFlipped() const
• public bool isPartial() const
• public bool isPhys() const
• public bool setRegisters(const llvm::MachineInstr *)

Methods

¶CoalescerPair(const llvm::TargetRegisterInfo& tri)

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:58

Parameters

const llvm::TargetRegisterInfo& tri

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

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:62

Parameters

unsigned int VirtReg

unsigned int PhysReg

const llvm::TargetRegisterInfo& tri

¶bool flip()

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:72

¶unsigned int getDstIdx() const

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:101

¶unsigned int getDstReg() const

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:95

¶const llvm::TargetRegisterClass* getNewRC() const

Description

Return the register class of the coalesced register.

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:107

¶unsigned int getSrcIdx() const

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:104

¶unsigned int getSrcReg() const

Description

Return the virtual register that will be coalesced away.

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:98

¶bool isCoalescable(
    const llvm::MachineInstr*) const

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:76

Parameters

const llvm::MachineInstr*

¶bool isCrossClass() const

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:87

¶bool isFlipped() const

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:91

¶bool isPartial() const

Description

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

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:83

¶bool isPhys() const

Description

Return true if DstReg is a physical register.

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:79

¶bool setRegisters(const llvm::MachineInstr*)

Description

Set registers to match the copy instruction MI. Return false if MI is not a coalescable copy instruction.

Declared at: llvm/lib/CodeGen/RegisterCoalescer.h:68

Parameters

const llvm::MachineInstr*