llvm::AntiDepBreaker Class Reference

This class works in conjunction with the post-RA scheduler to rename registers to break register anti-dependencies (WAR hazards). More...

#include "llvm/CodeGen/AntiDepBreaker.h"

Inheritance diagram for llvm::AntiDepBreaker:

Public Types
using	DbgValueVector = std::vector< std::pair< MachineInstr *, MachineInstr * > >

Public Member Functions
virtual	~AntiDepBreaker ()
virtual void	StartBlock (MachineBasicBlock *BB)=0
	Initialize anti-dep breaking for a new basic block.
virtual unsigned	BreakAntiDependencies (const std::vector< SUnit > &SUnits, MachineBasicBlock::iterator Begin, MachineBasicBlock::iterator End, unsigned InsertPosIndex, DbgValueVector &DbgValues)=0
	Identifiy anti-dependencies within a basic-block region and break them by renaming registers.
virtual void	Observe (MachineInstr &MI, unsigned Count, unsigned InsertPosIndex)=0
	Update liveness information to account for the current instruction, which will not be scheduled.
virtual void	FinishBlock ()=0
	Finish anti-dep breaking for a basic block.
void	UpdateDbgValue (MachineInstr &MI, unsigned OldReg, unsigned NewReg)
	Update DBG_VALUE or DBG_PHI if dependency breaker is updating other machine instruction to use NewReg.
void	UpdateDbgValues (const DbgValueVector &DbgValues, MachineInstr *ParentMI, unsigned OldReg, unsigned NewReg)
	Update all DBG_VALUE instructions that may be affected by the dependency breaker's update of ParentMI to use NewReg.

Detailed Description

This class works in conjunction with the post-RA scheduler to rename registers to break register anti-dependencies (WAR hazards).

Definition at line 31 of file AntiDepBreaker.h.

Member Typedef Documentation

DbgValueVector

using llvm::AntiDepBreaker::DbgValueVector = std::vector<std::pair<MachineInstr *, MachineInstr *> >

Definition at line 33 of file AntiDepBreaker.h.

Constructor & Destructor Documentation

~AntiDepBreaker()

AntiDepBreaker::~AntiDepBreaker ( )

virtualdefault

Member Function Documentation

BreakAntiDependencies()

virtual unsigned llvm::AntiDepBreaker::BreakAntiDependencies ( const std::vector< SUnit > &  SUnits, MachineBasicBlock::iterator  Begin, MachineBasicBlock::iterator  End, unsigned  InsertPosIndex, DbgValueVector &  DbgValues  )

pure virtual

Identifiy anti-dependencies within a basic-block region and break them by renaming registers.

Return the number of anti-dependencies broken.

Implemented in llvm::AggressiveAntiDepBreaker, and llvm::CriticalAntiDepBreaker.

FinishBlock()

virtual void llvm::AntiDepBreaker::FinishBlock ( )

pure virtual

Finish anti-dep breaking for a basic block.

Implemented in llvm::AggressiveAntiDepBreaker, and llvm::CriticalAntiDepBreaker.

Observe()

virtual void llvm::AntiDepBreaker::Observe ( MachineInstr &  MI, unsigned  Count, unsigned  InsertPosIndex  )

pure virtual

Update liveness information to account for the current instruction, which will not be scheduled.

Implemented in llvm::AggressiveAntiDepBreaker, and llvm::CriticalAntiDepBreaker.

StartBlock()

virtual void llvm::AntiDepBreaker::StartBlock ( MachineBasicBlock *  BB )

pure virtual

Initialize anti-dep breaking for a new basic block.

Implemented in llvm::AggressiveAntiDepBreaker, and llvm::CriticalAntiDepBreaker.

UpdateDbgValue()

void llvm::AntiDepBreaker::UpdateDbgValue ( MachineInstr &  MI, unsigned  OldReg, unsigned  NewReg  )

inline

Update DBG_VALUE or DBG_PHI if dependency breaker is updating other machine instruction to use NewReg.

Definition at line 59 of file AntiDepBreaker.h.

References llvm_unreachable, and MI.

Referenced by UpdateDbgValues().

UpdateDbgValues()

void llvm::AntiDepBreaker::UpdateDbgValues ( const DbgValueVector &  DbgValues, MachineInstr *  ParentMI, unsigned  OldReg, unsigned  NewReg  )

inline

Update all DBG_VALUE instructions that may be affected by the dependency breaker's update of ParentMI to use NewReg.

Definition at line 75 of file AntiDepBreaker.h.

References llvm::make_range(), and UpdateDbgValue().

Referenced by llvm::AggressiveAntiDepBreaker::BreakAntiDependencies(), and llvm::CriticalAntiDepBreaker::BreakAntiDependencies().

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

• include/llvm/CodeGen/AntiDepBreaker.h
• lib/CodeGen/PostRASchedulerList.cpp