LLVM: llvm::LiveRange Class Reference (original) (raw)

This class represents the liveness of a register, stack slot, etc. More...

#include "[llvm/CodeGen/LiveInterval.h](LiveInterval%5F8h%5Fsource.html)"

This class represents the liveness of a register, stack slot, etc.

It manages an ordered list of Segment objects. The Segments are organized in a static single assignment form: At places where a new value is defined or different values reach a CFG join a new segment with a new value number is used.

Definition at line 166 of file LiveInterval.h.

◆ const_iterator

◆ const_vni_iterator

◆ iterator

◆ Segments

◆ SegmentSet

◆ vni_iterator

◆ VNInfoList

Constructs a new LiveRange object.

Definition at line 248 of file LiveInterval.h.

References segmentSet.

Referenced by assign(), covers(), llvm::LiveInterval::createSubRangeFrom(), find(), join(), LiveRange(), MergeSegmentsInAsValue(), MergeValueInAsValue(), operator<(), overlaps(), overlaps(), overlapsFrom(), llvm::LiveInterval::SubRange::print(), and llvm::LiveInterval::SubRange::SubRange().

◆ LiveRange() [2/2]

◆ addSegment()

◆ advanceTo() [1/2]

◆ advanceTo() [2/2]

◆ append()

◆ assign()

Copies values numbers and live segments from Other into this range.

Definition at line 261 of file LiveInterval.h.

References Allocator, assert(), createValueCopy(), llvm::LiveRange::Segment::end, llvm::VNInfo::id, LiveRange(), llvm::Other, segments, llvm::LiveRange::Segment::start, llvm::LiveRange::Segment::valno, and valnos.

Referenced by LiveRange().

◆ begin() [1/2]

Definition at line 224 of file LiveInterval.h.

References segments.

Referenced by llvm::LiveIntervals::addKillFlags(), llvm::LiveIntervals::checkRegMaskInterference(), llvm::SplitAnalysis::countLiveBlocks(), covers(), llvm::SplitAnalysis::isOriginalEndpoint(), join(), MergeValueNumberInto(), overlaps(), overlaps(), overlapsFrom(), and verify().

◆ begin() [2/2]

◆ beginIndex()

◆ clear()

◆ containsOneValue()

◆ containsValue()

◆ covers()

Returns true if all segments of the Other live range are completely covered by this live range.

Adjacent live ranges do not affect the covering:the liverange [1,5](5,10] covers (3,7].

Definition at line 479 of file LiveInterval.cpp.

References advanceTo(), begin(), empty(), end(), I, llvm::Last, LiveRange(), and llvm::Other.

Referenced by llvm::LiveIntervals::HMEditor::updateAllRanges(), and llvm::LiveInterval::verify().

◆ createDeadDef() [1/2]

◆ createDeadDef() [2/2]

◆ createValueCopy()

Create a copy of the given value.

The new value will be identical except for the Value number.

Definition at line 358 of file LiveInterval.h.

References valnos.

Referenced by assign().

◆ dump()

◆ empty()

Definition at line 392 of file LiveInterval.h.

References segments.

Referenced by llvm::LiveIntervals::addKillFlags(), llvm::RegAllocBase::allocatePhysRegs(), beginIndex(), llvm::LiveIntervalCalc::calculate(), llvm::LiveRegMatrix::checkInterference(), llvm::LiveIntervals::checkRegMaskInterference(), llvm::LiveRegMatrix::checkRegUnitInterference(), llvm::SplitAnalysis::countLiveBlocks(), covers(), endIndex(), llvm::LiveIntervals::intervalIsInOneMBB(), llvm::SplitAnalysis::isOriginalEndpoint(), join(), overlaps(), overlaps(), overlapsFrom(), print(), and removeValNo().

◆ end() [1/2]

Definition at line 225 of file LiveInterval.h.

References segments.

Referenced by llvm::LiveRangeUpdater::add(), llvm::LiveIntervals::addKillFlags(), addSegment(), advanceTo(), advanceTo(), llvm::LiveIntervals::checkRegMaskInterference(), llvm::SplitAnalysis::countLiveBlocks(), covers(), FindSegmentContaining(), FindSegmentContaining(), getSegmentContaining(), getSegmentContaining(), getVNInfoAt(), getVNInfoBefore(), isLiveAtIndexes(), llvm::SplitAnalysis::isOriginalEndpoint(), join(), liveAt(), MergeValueNumberInto(), overlaps(), overlaps(), overlapsFrom(), Query(), removeSegment(), llvm::LiveDebugVariables::LDVImpl::splitPHIRegister(), and verify().

◆ end() [2/2]

◆ endIndex()

◆ expiredAt()

◆ extendInBlock() [1/2]

Attempt to extend a value defined after StartIdx to include [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users.").

Both StartIdx and [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users.") should be in the same basic block. In case of subranges, an extension could be prevented by an explicit "undef" caused by a <def,read-undef> on a non-overlapping lane. The list of location of such "undefs" should be provided in Undefs. The return value is a pair: the first element is VNInfo of the value that was extended (possibly nullptr), the second is a boolean value indicating whether an "undef" was encountered. If this range is live before [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users.") in the basic block that starts at StartIdx, and there is no intervening "undef", extend it to be live up to [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users."), and return the pair {value, false}. If there is no segment before [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users.") and there is no "undef" between StartIdx and [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users."), return {nullptr, false}. If there is an "undef" before [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users."), return {nullptr, true}.

Definition at line 549 of file LiveInterval.cpp.

References segmentSet.

Referenced by llvm::LiveRangeCalc::extend().

◆ extendInBlock() [2/2]

Simplified version of the above "extendInBlock", which assumes that no register lanes are undefined by <def,read-undef> operands.

If this range is live before [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users.") in the basic block that starts at StartIdx, extend it to be live up to [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users."), and return the value. If there is no segment before [Use](classllvm%5F1%5F1Use.html "A Use represents the edge between a Value definition and its users."), return nullptr.

Definition at line 558 of file LiveInterval.cpp.

References segmentSet.

◆ find() [1/2]

find - Return an iterator pointing to the first segment that ends after Pos, or end().

This is the same as advanceTo(begin(), Pos), but faster when searching large ranges.

If Pos is contained in a Segment, that segment is returned. If Pos is in a hole, the following Segment is returned. If Pos is beyond endIndex, end() is returned.

Definition at line 350 of file LiveInterval.cpp.

References find(), llvm::partition_point(), and X.

Referenced by llvm::LiveIntervals::addKillFlags(), find(), find(), FindSegmentContaining(), FindSegmentContaining(), isLiveAtIndexes(), llvm::SplitAnalysis::isOriginalEndpoint(), liveAt(), overlaps(), Query(), removeSegment(), and llvm::LiveDebugVariables::LDVImpl::splitPHIRegister().

◆ find() [2/2]

◆ findIndexesLiveAt()

template<typename Range, typename OutputIt>

Stores indexes from the input index sequence R at which this LiveRange is live to the output O iterator.

R is a range of ascending sorted random access iterators to the input indexes. Indexes stored at O are ascending sorted so it can be used directly in the subsequent search (for example for subranges). Returns true if found at least one index.

Definition at line 639 of file LiveInterval.h.

References assert(), llvm::is_sorted(), Range, and segments.

◆ FindSegmentContaining() [1/2]

◆ FindSegmentContaining() [2/2]

◆ flushSegmentSet()

Flush segment set into the regular segment vector.

The method is to be called after the live range has been created, if use of the segment set was activated in the constructor of the live range.

Definition at line 793 of file LiveInterval.cpp.

References assert(), segments, segmentSet, and verify().

◆ getNextValue()

getNextValue - Create a new value number and return it.

Def is the index of instruction that defines the value number.

Definition at line 340 of file LiveInterval.h.

References valnos.

◆ getNumValNums()

◆ getSegmentContaining() [1/2]

◆ getSegmentContaining() [2/2]

◆ getValNumInfo() [1/2]

◆ getValNumInfo() [2/2]

◆ getVNInfoAt()

getVNInfoAt - Return the VNInfo that is live at Idx, or NULL.

Definition at line 431 of file LiveInterval.h.

References end(), FindSegmentContaining(), and I.

Referenced by llvm::VirtRegAuxInfo::allUsesAvailableAt(), llvm::ConnectedVNInfoEqClasses::Distribute(), llvm::SIRegisterInfo::findReachingDef(), hasSingleUse(), llvm::VirtRegAuxInfo::isRematerializable(), moveAndTeeForMultiUse(), llvm::LiveIntervals::removePhysRegDefAt(), llvm::LiveIntervals::removeVRegDefAt(), replaceDominatedUses(), and llvm::MachineBasicBlock::SplitCriticalEdge().

◆ getVNInfoBefore()

◆ hasAtLeastOneValue()

◆ isLiveAtIndexes()

◆ isLocal()

True iff this segment is a single segment that lies between the specified boundaries, exclusively.

Vregs live across a backedge are not considered local. The boundaries are expected to lie within an extended basic block, so vregs that are not live out should contain no holes.

Definition at line 529 of file LiveInterval.h.

References beginIndex(), endIndex(), and llvm::SlotIndex::getBoundaryIndex().

◆ isUndefIn()

◆ isZeroLength()

◆ join()

join - Join two live ranges (this, and other) together.

This applies mappings to the value numbers in the LHS/RHS ranges as specified. If the ranges are not joinable, this aborts.

Definition at line 629 of file LiveInterval.cpp.

References llvm::LiveRangeUpdater::add(), assert(), begin(), empty(), end(), getNumValNums(), getValNumInfo(), I, llvm::VNInfo::id, LiveRange(), LiveRangeUpdater, llvm::Other, segments, llvm::SmallVectorTemplateCommon< T, typename >::size(), llvm::LiveRange::Segment::valno, valnos, and verify().

◆ liveAt()

Definition at line 411 of file LiveInterval.h.

References end(), and find().

Referenced by llvm::GCNDownwardRPTracker::advanceBeforeNext(), llvm::SystemZInstrInfo::foldMemoryOperandImpl(), llvm::getLiveLaneMask(), getLiveLanesAt(), llvm::RegPressureTracker::getLiveLanesAt(), llvm::LiveIntervals::isLiveInToMBB(), llvm::LiveIntervals::isLiveOutOfMBB(), rematerializeCheapDef(), replaceDominatedUses(), llvm::MachineBasicBlock::SplitCriticalEdge(), and subRangeLiveAt().

◆ MergeSegmentsInAsValue()

Merge all of the live segments of a specific val# in RHS into this live range as the specified value number.

Merge all of the segments in RHS into this live range as the specified value number.

The segments in RHS are allowed to overlap with segments in the current range, it will replace the value numbers of the overlaped live segments with the specified value number.

The segments in RHS are allowed to overlap with segments in the current range, but only if the overlapping segments have the specified value number.

Definition at line 713 of file LiveInterval.cpp.

References llvm::LiveRangeUpdater::add(), llvm::LiveRange::Segment::end, LiveRange(), LiveRangeUpdater, and llvm::LiveRange::Segment::start.

◆ MergeValueInAsValue()

◆ MergeValueNumberInto()

MergeValueNumberInto - This method is called when two value numbers are found to be equivalent.

MergeValueNumberInto - This method is called when two value nubmers are found to be equivalent.

This eliminates V1, replacing all segments with the V1 value number with the V2 value number. This can cause merging of V1/V2 values numbers and compaction of the value space.

Definition at line 738 of file LiveInterval.cpp.

References assert(), begin(), llvm::VNInfo::copyFrom(), end(), I, llvm::VNInfo::id, segments, and std::swap().

◆ operator<()

◆ overlaps() [1/3]

◆ overlaps() [2/3]

◆ overlaps() [3/3]

◆ overlapsFrom()

◆ print()

◆ Query()

Query Liveness at Idx.

The sub-instruction slot of Idx doesn't matter, only the instruction it refers to is considered.

Definition at line 553 of file LiveInterval.h.

References llvm::VNInfo::def, E(), end(), find(), llvm::SlotIndex::getBaseIndex(), I, llvm::SlotIndex::isEarlierInstr(), and llvm::SlotIndex::isSameInstr().

Referenced by llvm::ScheduleDAGMILive::computeCyclicCriticalPath(), llvm::RegisterOperands::detectDeadDefs(), llvm::ConnectedVNInfoEqClasses::Distribute(), llvm::LiveIntervals::handleMoveIntoNewBundle(), hasSingleUse(), isDefBetween(), isDefInSubRange(), llvm::VirtRegAuxInfo::isRematerializable(), llvm::LiveIntervals::pruneValue(), llvm::LiveIntervals::shrinkToUses(), llvm::LiveIntervals::shrinkToUses(), and llvm::ScheduleDAGMILive::updatePressureDiffs().

◆ removeSegment() [1/3]

◆ removeSegment() [2/3]

◆ removeSegment() [3/3]

Remove the specified interval from this live range.

Does nothing if interval is not part of this live range. Note that the interval must be within a single Segment in its entirety.

Definition at line 566 of file LiveInterval.cpp.

References assert(), end(), find(), I, removeValNoIfDead(), and segments.

Referenced by moveForSingleUse(), llvm::LiveIntervals::pruneValue(), removeDeadSegment(), removeSegment(), llvm::LiveIntervals::shrinkToUses(), and llvm::MachineBasicBlock::SplitCriticalEdge().

◆ removeValNo()

◆ removeValNoIfDead()

◆ RenumberValues()

◆ size()

◆ verify()

◆ vni_begin() [1/2]

◆ vni_begin() [2/2]

◆ vni_end() [1/2]

◆ vni_end() [2/2]

◆ vnis() [1/2]

◆ vnis() [2/2]

◆ LiveRangeUpdater

◆ segments

Segments llvm::LiveRange::segments

Definition at line 212 of file LiveInterval.h.

Referenced by append(), assign(), begin(), begin(), beginIndex(), clear(), llvm::LiveIntervalCalc::constructMainRangeFromSubranges(), empty(), end(), end(), endIndex(), findIndexesLiveAt(), flushSegmentSet(), llvm::LiveInterval::getSize(), isZeroLength(), join(), MergeValueNumberInto(), print(), removeSegment(), removeSegment(), removeValNo(), RenumberValues(), llvm::LiveIntervals::shrinkToUses(), llvm::LiveIntervals::shrinkToUses(), and size().

◆ segmentSet

std::unique_ptr<SegmentSet> llvm::LiveRange::segmentSet

◆ valnos

VNInfoList llvm::LiveRange::valnos

Definition at line 213 of file LiveInterval.h.

Referenced by assign(), llvm::ConnectedVNInfoEqClasses::Classify(), clear(), llvm::LiveIntervalCalc::constructMainRangeFromSubranges(), containsOneValue(), createValueCopy(), getNextValue(), getNumValNums(), getValNumInfo(), getValNumInfo(), hasAtLeastOneValue(), llvm::LiveIntervals::hasPHIKill(), join(), RenumberValues(), llvm::LiveIntervals::shrinkToUses(), stripValuesNotDefiningMask(), verify(), vni_begin(), vni_begin(), vni_end(), and vni_end().

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

• include/llvm/CodeGen/LiveInterval.h
• lib/CodeGen/LiveInterval.cpp