class SplitEditor

Declaration

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

Description

SplitEditor - Edit machine code and LiveIntervals for live range splitting. - Create a SplitEditor from a SplitAnalysis. - Start a new live interval with openIntv. - Mark the places where the new interval is entered using enterIntv* - Mark the ranges where the new interval is used with useIntv* - Mark the places where the interval is exited with exitIntv*. - Finish the current interval with closeIntv and repeat from 2. - Rewrite instructions with finish().

Declared at: llvm/lib/CodeGen/SplitKit.h:257

Method Overview

• public SplitEditor(llvm::SplitAnalysis & sa, llvm::AliasAnalysis & aa, llvm::LiveIntervals & lis, llvm::VirtRegMap & vrm, llvm::MachineDominatorTree & mdt, llvm::MachineBlockFrequencyInfo & mbfi)
• public unsigned int currentIntv() const
• public void dump() const
• public llvm::SlotIndex enterIntvAfter(llvm::SlotIndex Idx)
• public llvm::SlotIndex enterIntvAtEnd(llvm::MachineBasicBlock & MBB)
• public llvm::SlotIndex enterIntvBefore(llvm::SlotIndex Idx)
• public void finish(SmallVectorImpl<unsigned int> * LRMap = nullptr)
• public llvm::SlotIndex leaveIntvAfter(llvm::SlotIndex Idx)
• public llvm::SlotIndex leaveIntvAtTop(llvm::MachineBasicBlock & MBB)
• public llvm::SlotIndex leaveIntvBefore(llvm::SlotIndex Idx)
• public unsigned int openIntv()
• public void overlapIntv(llvm::SlotIndex Start, llvm::SlotIndex End)
• public void reset(llvm::LiveRangeEdit &, llvm::SplitEditor::ComplementSpillMode = SM_Partition)
• public void selectIntv(unsigned int Idx)
• public void splitLiveThroughBlock(unsigned int MBBNum, unsigned int IntvIn, llvm::SlotIndex LeaveBefore, unsigned int IntvOut, llvm::SlotIndex EnterAfter)
• public void splitRegInBlock(const SplitAnalysis::BlockInfo & BI, unsigned int IntvIn, llvm::SlotIndex LeaveBefore)
• public void splitRegOutBlock(const SplitAnalysis::BlockInfo & BI, unsigned int IntvOut, llvm::SlotIndex EnterAfter)
• public void splitSingleBlock(const SplitAnalysis::BlockInfo & BI)
• public void useIntv(llvm::SlotIndex Start, llvm::SlotIndex End)
• public void useIntv(const llvm::MachineBasicBlock & MBB)

Methods

¶SplitEditor(llvm::SplitAnalysis& sa,
            llvm::AliasAnalysis& aa,
            llvm::LiveIntervals& lis,
            llvm::VirtRegMap& vrm,
            llvm::MachineDominatorTree& mdt,
            llvm::MachineBlockFrequencyInfo& mbfi)

Description

Create a new SplitEditor for editing the LiveInterval analyzed by SA. Newly created intervals will be appended to newIntervals.

Declared at: llvm/lib/CodeGen/SplitKit.h:445

Parameters

llvm::SplitAnalysis& sa

llvm::AliasAnalysis& aa

llvm::LiveIntervals& lis

llvm::VirtRegMap& vrm

llvm::MachineDominatorTree& mdt

llvm::MachineBlockFrequencyInfo& mbfi

¶unsigned int currentIntv() const

Description

currentIntv - Return the current interval index.

Declared at: llvm/lib/CodeGen/SplitKit.h:458

¶void dump() const

Description

dump - print the current interval mapping to dbgs().

Declared at: llvm/lib/CodeGen/SplitKit.h:516

¶llvm::SlotIndex enterIntvAfter(
    llvm::SlotIndex Idx)

Description

enterIntvAfter - Enter the open interval after the instruction at Idx. Return the beginning of the new live range.

Declared at: llvm/lib/CodeGen/SplitKit.h:470

Parameters

llvm::SlotIndex Idx

¶llvm::SlotIndex enterIntvAtEnd(
    llvm::MachineBasicBlock& MBB)

Description

enterIntvAtEnd - Enter the open interval at the end of MBB. Use the open interval from the inserted copy to the MBB end. Return the beginning of the new live range.

Declared at: llvm/lib/CodeGen/SplitKit.h:475

Parameters

llvm::MachineBasicBlock& MBB

¶llvm::SlotIndex enterIntvBefore(
    llvm::SlotIndex Idx)

Description

enterIntvBefore - Enter the open interval before the instruction at Idx. If the parent interval is not live before Idx, a COPY is not inserted. Return the beginning of the new live range.

Declared at: llvm/lib/CodeGen/SplitKit.h:466

Parameters

llvm::SlotIndex Idx

¶void finish(SmallVectorImpl<unsigned int>* LRMap =
                nullptr)

Description

finish - after all the new live ranges have been created, compute the remaining live range, and rewrite instructions to use the new registers.

Declared at: llvm/lib/CodeGen/SplitKit.h:513

Parameters

SmallVectorImpl<unsigned int>* LRMap = nullptr

When not null, this vector will map each live range in Edit back to the indices returned by openIntv. There may be extra indices created by dead code elimination.

¶llvm::SlotIndex leaveIntvAfter(
    llvm::SlotIndex Idx)

Description

leaveIntvAfter - Leave the open interval after the instruction at Idx. Return the end of the live range.

Declared at: llvm/lib/CodeGen/SplitKit.h:485

Parameters

llvm::SlotIndex Idx

¶llvm::SlotIndex leaveIntvAtTop(
    llvm::MachineBasicBlock& MBB)

Description

leaveIntvAtTop - Leave the interval at the top of MBB. Add liveness from the MBB top to the copy. Return the end of the live range.

Declared at: llvm/lib/CodeGen/SplitKit.h:494

Parameters

llvm::MachineBasicBlock& MBB

¶llvm::SlotIndex leaveIntvBefore(
    llvm::SlotIndex Idx)

Description

leaveIntvBefore - Leave the open interval before the instruction at Idx. Return the end of the live range.

Declared at: llvm/lib/CodeGen/SplitKit.h:489

Parameters

llvm::SlotIndex Idx

¶unsigned int openIntv()

Description

Create a new virtual register and live interval. Return the interval index, starting from 1. Interval index 0 is the implicit complement interval.

Declared at: llvm/lib/CodeGen/SplitKit.h:455

¶void overlapIntv(llvm::SlotIndex Start,
                 llvm::SlotIndex End)

Description

overlapIntv - Indicate that all instructions in range should use the open interval, but also let the complement interval be live. This doubles the register pressure, but is sometimes required to deal with register uses after the last valid split point. The Start index should be a return value from a leaveIntv* call, and End should be in the same basic block. The parent interval must have the same value across the range.

Declared at: llvm/lib/CodeGen/SplitKit.h:506

Parameters

llvm::SlotIndex Start

llvm::SlotIndex End

¶void reset(
    llvm::LiveRangeEdit&,
    llvm::SplitEditor::ComplementSpillMode =
        SM_Partition)

Description

reset - Prepare for a new split.

Declared at: llvm/lib/CodeGen/SplitKit.h:450

Parameters

llvm::LiveRangeEdit&

llvm::SplitEditor::ComplementSpillMode = SM_Partition

¶void selectIntv(unsigned int Idx)

Description

selectIntv - Select a previously opened interval index.

Declared at: llvm/lib/CodeGen/SplitKit.h:461

Parameters

unsigned int Idx

¶void splitLiveThroughBlock(
    unsigned int MBBNum,
    unsigned int IntvIn,
    llvm::SlotIndex LeaveBefore,
    unsigned int IntvOut,
    llvm::SlotIndex EnterAfter)

Description

splitLiveThroughBlock - Split CurLI in the given block such that it enters the block in IntvIn and leaves it in IntvOut. There may be uses in the block, but they will be ignored when placing split points.

Declared at: llvm/lib/CodeGen/SplitKit.h:534

Parameters

unsigned int MBBNum

Block number.

unsigned int IntvIn

Interval index entering the block.

llvm::SlotIndex LeaveBefore

When set, leave IntvIn before this point.

unsigned int IntvOut

Interval index leaving the block.

llvm::SlotIndex EnterAfter

When set, enter IntvOut after this point.

¶void splitRegInBlock(
    const SplitAnalysis::BlockInfo& BI,
    unsigned int IntvIn,
    llvm::SlotIndex LeaveBefore)

Description

splitRegInBlock - Split CurLI in the given block such that it enters the block in IntvIn and leaves it on the stack (or not at all). Split points are placed in a way that avoids putting uses in the stack interval. This may require creating a local interval when there is interference.

Declared at: llvm/lib/CodeGen/SplitKit.h:546

Parameters

const SplitAnalysis::BlockInfo& BI

Block descriptor.

unsigned int IntvIn

Interval index entering the block. Not 0.

llvm::SlotIndex LeaveBefore

When set, leave IntvIn before this point.

¶void splitRegOutBlock(
    const SplitAnalysis::BlockInfo& BI,
    unsigned int IntvOut,
    llvm::SlotIndex EnterAfter)

Description

splitRegOutBlock - Split CurLI in the given block such that it enters the block on the stack (or isn't live-in at all) and leaves it in IntvOut. Split points are placed to avoid interference and such that the uses are not in the stack interval. This may require creating a local interval when there is interference.

Declared at: llvm/lib/CodeGen/SplitKit.h:558

Parameters

const SplitAnalysis::BlockInfo& BI

Block descriptor.

unsigned int IntvOut

Interval index leaving the block.

llvm::SlotIndex EnterAfter

When set, enter IntvOut after this point.

¶void splitSingleBlock(
    const SplitAnalysis::BlockInfo& BI)

Description

splitSingleBlock - Split CurLI into a separate live interval around the uses in a single block. This is intended to be used as part of a larger split, and doesn't call finish().

Declared at: llvm/lib/CodeGen/SplitKit.h:523

Parameters

const SplitAnalysis::BlockInfo& BI

¶void useIntv(llvm::SlotIndex Start,
             llvm::SlotIndex End)

Description

useIntv - indicate that all instructions in range should use OpenLI.

Declared at: llvm/lib/CodeGen/SplitKit.h:481

Parameters

llvm::SlotIndex Start

llvm::SlotIndex End

¶void useIntv(const llvm::MachineBasicBlock& MBB)

Description

useIntv - indicate that all instructions in MBB should use OpenLI.

Declared at: llvm/lib/CodeGen/SplitKit.h:478

Parameters

const llvm::MachineBasicBlock& MBB