SplitAnalysis - Analyze a LiveInterval, looking for live range splitting opportunities. More...

#include "CodeGen/SplitKit.h"

Classes
struct	BlockInfo
	Additional information about basic blocks where the current variable is live. More...

Public Types
using	BlockPtrSet = SmallPtrSet<const MachineBasicBlock *, 16>

Public Member Functions
	SplitAnalysis (const VirtRegMap &vrm, const LiveIntervals &lis, const MachineLoopInfo &mli)
void	analyze (const LiveInterval *li)
	analyze - set CurLI to the specified interval, and analyze how it may be split.
void	clear ()
	clear - clear all data structures so SplitAnalysis is ready to analyze a new interval.
const LiveInterval &	getParent () const
	getParent - Return the last analyzed interval.
bool	isOriginalEndpoint (SlotIndex Idx) const
	isOriginalEndpoint - Return true if the original live range was killed or (re-)defined at Idx.
ArrayRef< SlotIndex >	getUseSlots () const
	getUseSlots - Return an array of SlotIndexes of instructions using CurLI.
ArrayRef< BlockInfo >	getUseBlocks () const
	getUseBlocks - Return an array of BlockInfo objects for the basic blocks where CurLI has uses.
unsigned	getNumThroughBlocks () const
	getNumThroughBlocks - Return the number of through blocks.
bool	isThroughBlock (unsigned MBB) const
	isThroughBlock - Return true if CurLI is live through MBB without uses.
const BitVector &	getThroughBlocks () const
	getThroughBlocks - Return the set of through blocks.
unsigned	getNumLiveBlocks () const
	getNumLiveBlocks - Return the number of blocks where CurLI is live.
bool	looksLikeLoopIV () const
unsigned	countLiveBlocks (const LiveInterval *li) const
	countLiveBlocks - Return the number of blocks where li is live.
bool	shouldSplitSingleBlock (const BlockInfo &BI, bool SingleInstrs) const
	shouldSplitSingleBlock - Returns true if it would help to create a local live range for the instructions in BI.
SlotIndex	getLastSplitPoint (unsigned Num)
SlotIndex	getLastSplitPoint (MachineBasicBlock *BB)
MachineBasicBlock::iterator	getLastSplitPointIter (MachineBasicBlock *BB)
SlotIndex	getFirstSplitPoint (unsigned Num)

Public Attributes
const MachineFunction &	MF
const VirtRegMap &	VRM
const LiveIntervals &	LIS
const MachineLoopInfo &	Loops
const TargetInstrInfo &	TII

Detailed Description

SplitAnalysis - Analyze a LiveInterval, looking for live range splitting opportunities.

Definition at line 96 of file SplitKit.h.

Member Typedef Documentation

◆ BlockPtrSet

using llvm::SplitAnalysis::BlockPtrSet = SmallPtrSet<const MachineBasicBlock *, 16>

Definition at line 223 of file SplitKit.h.

Constructor & Destructor Documentation

◆ SplitAnalysis()

SplitAnalysis::SplitAnalysis	(	const VirtRegMap &	vrm,
		const LiveIntervals &	lis,
		const MachineLoopInfo &	mli )

Definition at line 154 of file SplitKit.cpp.

References LIS, Loops, MF, TII, and VRM.

Member Function Documentation

◆ analyze()

void SplitAnalysis::analyze ( const LiveInterval * li )

analyze - set CurLI to the specified interval, and analyze how it may be split.

Definition at line 347 of file SplitKit.cpp.

References clear().

◆ clear()

void SplitAnalysis::clear ( )

clear - clear all data structures so SplitAnalysis is ready to analyze a new interval.

Definition at line 159 of file SplitKit.cpp.

Referenced by analyze().

◆ countLiveBlocks()

unsigned SplitAnalysis::countLiveBlocks ( const LiveInterval * li ) const

countLiveBlocks - Return the number of blocks where li is live.

This is guaranteed to return the same number as getNumLiveBlocks() after calling analyze(li).

Definition at line 309 of file SplitKit.cpp.

References llvm::LiveRange::advanceTo(), llvm::LiveRange::begin(), llvm::Count, llvm::LiveRange::empty(), llvm::LiveRange::end(), and LIS.

◆ getFirstSplitPoint()

SlotIndex llvm::SplitAnalysis::getFirstSplitPoint ( unsigned Num )

inline

Definition at line 247 of file SplitKit.h.

References MF.

◆ getLastSplitPoint() [1/2]

SlotIndex llvm::SplitAnalysis::getLastSplitPoint ( MachineBasicBlock * BB )

inline

Definition at line 239 of file SplitKit.h.

◆ getLastSplitPoint() [2/2]

SlotIndex llvm::SplitAnalysis::getLastSplitPoint ( unsigned Num )

inline

Definition at line 235 of file SplitKit.h.

References MF.

◆ getLastSplitPointIter()

MachineBasicBlock::iterator llvm::SplitAnalysis::getLastSplitPointIter ( MachineBasicBlock * BB )

inline

Definition at line 243 of file SplitKit.h.

◆ getNumLiveBlocks()

unsigned llvm::SplitAnalysis::getNumLiveBlocks ( ) const

inline

getNumLiveBlocks - Return the number of blocks where CurLI is live.

Definition at line 212 of file SplitKit.h.

References getNumThroughBlocks(), and getUseBlocks().

◆ getNumThroughBlocks()

unsigned llvm::SplitAnalysis::getNumThroughBlocks ( ) const

inline

getNumThroughBlocks - Return the number of through blocks.

Definition at line 203 of file SplitKit.h.

Referenced by getNumLiveBlocks().

◆ getParent()

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

inline

getParent - Return the last analyzed interval.

Definition at line 185 of file SplitKit.h.

◆ getThroughBlocks()

const BitVector & llvm::SplitAnalysis::getThroughBlocks ( ) const

inline

getThroughBlocks - Return the set of through blocks.

Definition at line 209 of file SplitKit.h.

◆ getUseBlocks()

ArrayRef< BlockInfo > llvm::SplitAnalysis::getUseBlocks ( ) const

inline

getUseBlocks - Return an array of BlockInfo objects for the basic blocks where CurLI has uses.

Definition at line 200 of file SplitKit.h.

Referenced by getNumLiveBlocks().

◆ getUseSlots()

ArrayRef< SlotIndex > llvm::SplitAnalysis::getUseSlots ( ) const

inline

getUseSlots - Return an array of SlotIndexes of instructions using CurLI.

This include both use and def operands, at most one entry per instruction.

Definition at line 196 of file SplitKit.h.

◆ isOriginalEndpoint()

bool SplitAnalysis::isOriginalEndpoint ( SlotIndex Idx ) const

isOriginalEndpoint - Return true if the original live range was killed or (re-)defined at Idx.

Idx should be the 'def' slot for a normal kill/def, and 'use' for an early-clobber def. This can be used to recognize code inserted by earlier live range splitting.

Definition at line 333 of file SplitKit.cpp.

References assert(), llvm::LiveRange::begin(), llvm::LiveRange::empty(), llvm::LiveRange::end(), llvm::LiveRange::find(), I, LIS, and VRM.

Referenced by shouldSplitSingleBlock().

◆ isThroughBlock()

bool llvm::SplitAnalysis::isThroughBlock ( unsigned MBB ) const

inline

isThroughBlock - Return true if CurLI is live through MBB without uses.

Definition at line 206 of file SplitKit.h.

References MBB.

◆ looksLikeLoopIV()

bool llvm::SplitAnalysis::looksLikeLoopIV ( ) const

inline

Definition at line 216 of file SplitKit.h.

◆ shouldSplitSingleBlock()

bool SplitAnalysis::shouldSplitSingleBlock	(	const BlockInfo &	BI,
		bool	SingleInstrs ) const

shouldSplitSingleBlock - Returns true if it would help to create a local live range for the instructions in BI.

There is normally no benefit to creating a live range for a single instruction, but it does enable register class inflation if the instruction has a restricted register class.

Parameters

BI	The block to be isolated.
SingleInstrs	True when single instructions should be isolated.

Definition at line 1624 of file SplitKit.cpp.

References llvm::SplitAnalysis::BlockInfo::FirstInstr, llvm::SplitAnalysis::BlockInfo::isOneInstr(), isOriginalEndpoint(), LIS, llvm::SplitAnalysis::BlockInfo::LiveIn, llvm::SplitAnalysis::BlockInfo::LiveOut, MI, and TII.

Member Data Documentation

◆ LIS

const LiveIntervals& llvm::SplitAnalysis::LIS

Definition at line 100 of file SplitKit.h.

Referenced by countLiveBlocks(), isOriginalEndpoint(), shouldSplitSingleBlock(), and SplitAnalysis().

◆ Loops

const MachineLoopInfo& llvm::SplitAnalysis::Loops

Definition at line 101 of file SplitKit.h.

Referenced by SplitAnalysis().

◆ MF

const MachineFunction& llvm::SplitAnalysis::MF

Definition at line 98 of file SplitKit.h.

Referenced by getFirstSplitPoint(), getLastSplitPoint(), and SplitAnalysis().

◆ TII

const TargetInstrInfo& llvm::SplitAnalysis::TII

Definition at line 102 of file SplitKit.h.

Referenced by shouldSplitSingleBlock(), and SplitAnalysis().

◆ VRM

const VirtRegMap& llvm::SplitAnalysis::VRM

Definition at line 99 of file SplitKit.h.

Referenced by isOriginalEndpoint(), and SplitAnalysis().

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

lib/CodeGen/SplitKit.h
lib/CodeGen/SplitKit.cpp

Classes

Public Types

Public Member Functions

Public Attributes

Detailed Description

Member Typedef Documentation

◆ BlockPtrSet

Constructor & Destructor Documentation

◆ SplitAnalysis()

Member Function Documentation

◆ analyze()

◆ clear()

◆ countLiveBlocks()

◆ getFirstSplitPoint()

◆ getLastSplitPoint() [1/2]

◆ getLastSplitPoint() [2/2]

◆ getLastSplitPointIter()

◆ getNumLiveBlocks()

◆ getNumThroughBlocks()

◆ getParent()

◆ getThroughBlocks()

◆ getUseBlocks()

◆ getUseSlots()

◆ isOriginalEndpoint()

◆ isThroughBlock()

◆ looksLikeLoopIV()

◆ shouldSplitSingleBlock()

Member Data Documentation

◆ LIS

◆ Loops

◆ MF

◆ TII

◆ VRM