//
// This file implements the LiveRange and LiveInterval classes. Given some
// numbering of each the machine instructions an interval [i, j) is said to be a
-// live interval for register v if there is no instruction with number j' >= j
+// live range for register v if there is no instruction with number j' >= j
// such that v is live at j' and there is no instruction with number i' < i such
-// that v is live at i'. In this implementation intervals can have holes,
-// i.e. an interval might look like [1,20), [50,65), [1000,1001). Each
-// individual range is represented as an instance of LiveRange, and the whole
-// interval is represented as an instance of LiveInterval.
+// that v is live at i'. In this implementation ranges can have holes,
+// i.e. a range might look like [1,20), [50,65), [1000,1001). Each
+// individual segment is represented as an instance of LiveRange::Segment,
+// and the whole range is represented as an instance of LiveRange.
//
//===----------------------------------------------------------------------===//
class MachineRegisterInfo;
class TargetRegisterInfo;
class raw_ostream;
+ template <typename T, unsigned Small> class SmallPtrSet;
/// VNInfo - Value Number Information.
/// This class holds information about a machine level values, including
}
/// Returns true if this value is defined by a PHI instruction (or was,
- /// PHI instrucions may have been eliminated).
+ /// PHI instructions may have been eliminated).
/// PHI-defs begin at a block boundary, all other defs begin at register or
/// EC slots.
bool isPHIDef() const { return def.isBlock(); }
void markUnused() { def = SlotIndex(); }
};
- /// LiveRange structure - This represents a simple register range in the
- /// program, with an inclusive start point and an exclusive end point.
- /// These ranges are rendered as [start,end).
- struct LiveRange {
- SlotIndex start; // Start point of the interval (inclusive)
- SlotIndex end; // End point of the interval (exclusive)
- VNInfo *valno; // identifier for the value contained in this interval.
+ /// Result of a LiveRange query. This class hides the implementation details
+ /// of live ranges, and it should be used as the primary interface for
+ /// examining live ranges around instructions.
+ class LiveQueryResult {
+ VNInfo *const EarlyVal;
+ VNInfo *const LateVal;
+ const SlotIndex EndPoint;
+ const bool Kill;
- LiveRange() : valno(0) {}
+ public:
+ LiveQueryResult(VNInfo *EarlyVal, VNInfo *LateVal, SlotIndex EndPoint,
+ bool Kill)
+ : EarlyVal(EarlyVal), LateVal(LateVal), EndPoint(EndPoint), Kill(Kill)
+ {}
- LiveRange(SlotIndex S, SlotIndex E, VNInfo *V)
- : start(S), end(E), valno(V) {
- assert(S < E && "Cannot create empty or backwards range");
+ /// Return the value that is live-in to the instruction. This is the value
+ /// that will be read by the instruction's use operands. Return NULL if no
+ /// value is live-in.
+ VNInfo *valueIn() const {
+ return EarlyVal;
}
- /// contains - Return true if the index is covered by this range.
- ///
- bool contains(SlotIndex I) const {
- return start <= I && I < end;
+ /// Return true if the live-in value is killed by this instruction. This
+ /// means that either the live range ends at the instruction, or it changes
+ /// value.
+ bool isKill() const {
+ return Kill;
}
- /// containsRange - Return true if the given range, [S, E), is covered by
- /// this range.
- bool containsRange(SlotIndex S, SlotIndex E) const {
- assert((S < E) && "Backwards interval?");
- return (start <= S && S < end) && (start < E && E <= end);
+ /// Return true if this instruction has a dead def.
+ bool isDeadDef() const {
+ return EndPoint.isDead();
}
- bool operator<(const LiveRange &LR) const {
- return start < LR.start || (start == LR.start && end < LR.end);
+ /// Return the value leaving the instruction, if any. This can be a
+ /// live-through value, or a live def. A dead def returns NULL.
+ VNInfo *valueOut() const {
+ return isDeadDef() ? nullptr : LateVal;
}
- bool operator==(const LiveRange &LR) const {
- return start == LR.start && end == LR.end;
+
+ /// Return the value defined by this instruction, if any. This includes
+ /// dead defs, it is the value created by the instruction's def operands.
+ VNInfo *valueDefined() const {
+ return EarlyVal == LateVal ? nullptr : LateVal;
}
- void dump() const;
- void print(raw_ostream &os) const;
+ /// Return the end point of the last live range segment to interact with
+ /// the instruction, if any.
+ ///
+ /// The end point is an invalid SlotIndex only if the live range doesn't
+ /// intersect the instruction at all.
+ ///
+ /// The end point may be at or past the end of the instruction's basic
+ /// block. That means the value was live out of the block.
+ SlotIndex endPoint() const {
+ return EndPoint;
+ }
};
- template <> struct isPodLike<LiveRange> { static const bool value = true; };
+ /// 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.
+ class LiveRange {
+ public:
- raw_ostream& operator<<(raw_ostream& os, const LiveRange &LR);
+ /// This represents a simple continuous liveness interval for a value.
+ /// The start point is inclusive, the end point exclusive. These intervals
+ /// are rendered as [start,end).
+ struct Segment {
+ SlotIndex start; // Start point of the interval (inclusive)
+ SlotIndex end; // End point of the interval (exclusive)
+ VNInfo *valno; // identifier for the value contained in this segment.
+ Segment() : valno(nullptr) {}
- inline bool operator<(SlotIndex V, const LiveRange &LR) {
- return V < LR.start;
- }
+ Segment(SlotIndex S, SlotIndex E, VNInfo *V)
+ : start(S), end(E), valno(V) {
+ assert(S < E && "Cannot create empty or backwards segment");
+ }
- inline bool operator<(const LiveRange &LR, SlotIndex V) {
- return LR.start < V;
- }
+ /// Return true if the index is covered by this segment.
+ bool contains(SlotIndex I) const {
+ return start <= I && I < end;
+ }
- /// LiveInterval - This class represents some number of live ranges for a
- /// register or value. This class also contains a bit of register allocator
- /// state.
- class LiveInterval {
- public:
+ /// Return true if the given interval, [S, E), is covered by this segment.
+ bool containsInterval(SlotIndex S, SlotIndex E) const {
+ assert((S < E) && "Backwards interval?");
+ return (start <= S && S < end) && (start < E && E <= end);
+ }
+
+ bool operator<(const Segment &Other) const {
+ return std::tie(start, end) < std::tie(Other.start, Other.end);
+ }
+ bool operator==(const Segment &Other) const {
+ return start == Other.start && end == Other.end;
+ }
- typedef SmallVector<LiveRange,4> Ranges;
+ void dump() const;
+ };
+
+ typedef SmallVector<Segment,4> Segments;
typedef SmallVector<VNInfo*,4> VNInfoList;
- const unsigned reg; // the register or stack slot of this interval.
- float weight; // weight of this interval
- Ranges ranges; // the ranges in which this register is live
+ Segments segments; // the liveness segments
VNInfoList valnos; // value#'s
- LiveInterval(unsigned Reg, float Weight)
- : reg(Reg), weight(Weight) {}
-
- typedef Ranges::iterator iterator;
- iterator begin() { return ranges.begin(); }
- iterator end() { return ranges.end(); }
+ typedef Segments::iterator iterator;
+ iterator begin() { return segments.begin(); }
+ iterator end() { return segments.end(); }
- typedef Ranges::const_iterator const_iterator;
- const_iterator begin() const { return ranges.begin(); }
- const_iterator end() const { return ranges.end(); }
+ typedef Segments::const_iterator const_iterator;
+ const_iterator begin() const { return segments.begin(); }
+ const_iterator end() const { return segments.end(); }
typedef VNInfoList::iterator vni_iterator;
vni_iterator vni_begin() { return valnos.begin(); }
- vni_iterator vni_end() { return valnos.end(); }
+ vni_iterator vni_end() { return valnos.end(); }
typedef VNInfoList::const_iterator const_vni_iterator;
const_vni_iterator vni_begin() const { return valnos.begin(); }
- const_vni_iterator vni_end() const { return valnos.end(); }
+ const_vni_iterator vni_end() const { return valnos.end(); }
- /// advanceTo - Advance the specified iterator to point to the LiveRange
+ /// advanceTo - Advance the specified iterator to point to the Segment
/// containing the specified position, or end() if the position is past the
- /// end of the interval. If no LiveRange contains this position, but the
+ /// end of the range. If no Segment contains this position, but the
/// position is in a hole, this method returns an iterator pointing to the
- /// LiveRange immediately after the hole.
+ /// Segment immediately after the hole.
iterator advanceTo(iterator I, SlotIndex Pos) {
assert(I != end());
if (Pos >= endIndex())
return I;
}
- /// find - Return an iterator pointing to the first range that ends after
+ /// 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 intervals.
+ /// when searching large ranges.
///
- /// If Pos is contained in a LiveRange, that range is returned.
- /// If Pos is in a hole, the following LiveRange is returned.
+ /// 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.
iterator find(SlotIndex Pos);
const_iterator find(SlotIndex Pos) const {
- return const_cast<LiveInterval*>(this)->find(Pos);
+ return const_cast<LiveRange*>(this)->find(Pos);
}
void clear() {
valnos.clear();
- ranges.clear();
+ segments.clear();
+ }
+
+ size_t size() const {
+ return segments.size();
}
bool hasAtLeastOneValue() const { return !valnos.empty(); }
return valnos[ValNo];
}
- /// containsValue - Returns true if VNI belongs to this interval.
+ /// containsValue - Returns true if VNI belongs to this range.
bool containsValue(const VNInfo *VNI) const {
return VNI && VNI->id < getNumValNums() && VNI == getValNumInfo(VNI->id);
}
return VNI;
}
- /// createDeadDef - Make sure the interval has a value defined at Def.
+ /// createDeadDef - Make sure the range has a value defined at Def.
/// If one already exists, return it. Otherwise allocate a new value and
/// add liveness for a dead def.
VNInfo *createDeadDef(SlotIndex Def, VNInfo::Allocator &VNInfoAllocator);
/// MergeValueNumberInto - This method is called when two value numbers
/// are found to be equivalent. This eliminates V1, replacing all
- /// LiveRanges with the V1 value number with the V2 value number. This can
+ /// 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.
VNInfo* MergeValueNumberInto(VNInfo *V1, VNInfo *V2);
- /// MergeValueInAsValue - Merge all of the live ranges of a specific val#
- /// in RHS into this live interval as the specified value number.
- /// The LiveRanges in RHS are allowed to overlap with LiveRanges in the
- /// current interval, it will replace the value numbers of the overlaped
- /// live ranges with the specified value number.
- void MergeRangesInAsValue(const LiveInterval &RHS, VNInfo *LHSValNo);
-
- /// MergeValueInAsValue - Merge all of the live ranges of a specific val#
- /// in RHS into this live interval as the specified value number.
- /// The LiveRanges in RHS are allowed to overlap with LiveRanges in the
- /// current interval, but only if the overlapping LiveRanges have the
+ /// Merge all of the live segments of a specific val# 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.
+ void MergeSegmentsInAsValue(const LiveRange &RHS, VNInfo *LHSValNo);
+
+ /// MergeValueInAsValue - Merge all of the segments of a specific val#
+ /// 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, but only if the overlapping segments have the
/// specified value number.
- void MergeValueInAsValue(const LiveInterval &RHS,
+ void MergeValueInAsValue(const LiveRange &RHS,
const VNInfo *RHSValNo, VNInfo *LHSValNo);
- bool empty() const { return ranges.empty(); }
+ bool empty() const { return segments.empty(); }
- /// beginIndex - Return the lowest numbered slot covered by interval.
+ /// beginIndex - Return the lowest numbered slot covered.
SlotIndex beginIndex() const {
- assert(!empty() && "Call to beginIndex() on empty interval.");
- return ranges.front().start;
+ assert(!empty() && "Call to beginIndex() on empty range.");
+ return segments.front().start;
}
- /// endNumber - return the maximum point of the interval of the whole,
+ /// endNumber - return the maximum point of the range of the whole,
/// exclusive.
SlotIndex endIndex() const {
- assert(!empty() && "Call to endIndex() on empty interval.");
- return ranges.back().end;
+ assert(!empty() && "Call to endIndex() on empty range.");
+ return segments.back().end;
}
bool expiredAt(SlotIndex index) const {
return r != end() && r->start <= index;
}
- /// getLiveRangeContaining - Return the live range that contains the
- /// specified index, or null if there is none.
- const LiveRange *getLiveRangeContaining(SlotIndex Idx) const {
- const_iterator I = FindLiveRangeContaining(Idx);
- return I == end() ? 0 : &*I;
+ /// Return the segment that contains the specified index, or null if there
+ /// is none.
+ const Segment *getSegmentContaining(SlotIndex Idx) const {
+ const_iterator I = FindSegmentContaining(Idx);
+ return I == end() ? nullptr : &*I;
}
- /// getLiveRangeContaining - Return the live range that contains the
- /// specified index, or null if there is none.
- LiveRange *getLiveRangeContaining(SlotIndex Idx) {
- iterator I = FindLiveRangeContaining(Idx);
- return I == end() ? 0 : &*I;
+ /// Return the live segment that contains the specified index, or null if
+ /// there is none.
+ Segment *getSegmentContaining(SlotIndex Idx) {
+ iterator I = FindSegmentContaining(Idx);
+ return I == end() ? nullptr : &*I;
}
/// getVNInfoAt - Return the VNInfo that is live at Idx, or NULL.
VNInfo *getVNInfoAt(SlotIndex Idx) const {
- const_iterator I = FindLiveRangeContaining(Idx);
- return I == end() ? 0 : I->valno;
+ const_iterator I = FindSegmentContaining(Idx);
+ return I == end() ? nullptr : I->valno;
}
/// getVNInfoBefore - Return the VNInfo that is live up to but not
/// necessarilly including Idx, or NULL. Use this to find the reaching def
/// used by an instruction at this SlotIndex position.
VNInfo *getVNInfoBefore(SlotIndex Idx) const {
- const_iterator I = FindLiveRangeContaining(Idx.getPrevSlot());
- return I == end() ? 0 : I->valno;
+ const_iterator I = FindSegmentContaining(Idx.getPrevSlot());
+ return I == end() ? nullptr : I->valno;
}
- /// FindLiveRangeContaining - Return an iterator to the live range that
- /// contains the specified index, or end() if there is none.
- iterator FindLiveRangeContaining(SlotIndex Idx) {
+ /// Return an iterator to the segment that contains the specified index, or
+ /// end() if there is none.
+ iterator FindSegmentContaining(SlotIndex Idx) {
iterator I = find(Idx);
return I != end() && I->start <= Idx ? I : end();
}
- const_iterator FindLiveRangeContaining(SlotIndex Idx) const {
+ const_iterator FindSegmentContaining(SlotIndex Idx) const {
const_iterator I = find(Idx);
return I != end() && I->start <= Idx ? I : end();
}
- /// overlaps - Return true if the intersection of the two live intervals is
+ /// overlaps - Return true if the intersection of the two live ranges is
/// not empty.
- bool overlaps(const LiveInterval& other) const {
+ bool overlaps(const LiveRange &other) const {
if (other.empty())
return false;
return overlapsFrom(other, other.begin());
}
- /// overlaps - Return true if the two intervals have overlapping segments
+ /// overlaps - Return true if the two ranges have overlapping segments
/// that are not coalescable according to CP.
///
- /// Overlapping segments where one interval is defined by a coalescable
+ /// Overlapping segments where one range is defined by a coalescable
/// copy are allowed.
- bool overlaps(const LiveInterval &Other, const CoalescerPair &CP,
+ bool overlaps(const LiveRange &Other, const CoalescerPair &CP,
const SlotIndexes&) const;
- /// overlaps - Return true if the live interval overlaps a range specified
+ /// overlaps - Return true if the live range overlaps an interval specified
/// by [Start, End).
bool overlaps(SlotIndex Start, SlotIndex End) const;
- /// overlapsFrom - Return true if the intersection of the two live intervals
+ /// overlapsFrom - Return true if the intersection of the two live ranges
/// is not empty. The specified iterator is a hint that we can begin
- /// scanning the Other interval starting at I.
- bool overlapsFrom(const LiveInterval& other, const_iterator I) const;
+ /// scanning the Other range starting at I.
+ bool overlapsFrom(const LiveRange &Other, const_iterator I) const;
- /// addRange - Add the specified LiveRange to this interval, merging
- /// intervals as appropriate. This returns an iterator to the inserted live
- /// range (which may have grown since it was inserted.
- iterator addRange(LiveRange LR) {
- return addRangeFrom(LR, ranges.begin());
+ /// Add the specified Segment to this range, merging segments as
+ /// appropriate. This returns an iterator to the inserted segment (which
+ /// may have grown since it was inserted).
+ iterator addSegment(Segment S) {
+ return addSegmentFrom(S, segments.begin());
}
- /// extendInBlock - If this interval is live before Kill in the basic block
+ /// extendInBlock - If this range is live before Kill in the basic block
/// that starts at StartIdx, extend it to be live up to Kill, and return
- /// the value. If there is no live range before Kill, return NULL.
+ /// the value. If there is no segment before Kill, return NULL.
VNInfo *extendInBlock(SlotIndex StartIdx, SlotIndex Kill);
- /// join - Join two live intervals (this, and other) together. This applies
- /// mappings to the value numbers in the LHS/RHS intervals as specified. If
- /// the intervals are not joinable, this aborts.
- void join(LiveInterval &Other,
+ /// 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.
+ void join(LiveRange &Other,
const int *ValNoAssignments,
const int *RHSValNoAssignments,
SmallVectorImpl<VNInfo *> &NewVNInfo);
- /// True iff this live range is a single segment that lies between the
+ /// 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.
endIndex() < End.getBoundaryIndex();
}
- /// removeRange - Remove the specified range from this interval. Note that
- /// the range must be a single LiveRange in its entirety.
- void removeRange(SlotIndex Start, SlotIndex End,
- bool RemoveDeadValNo = false);
+ /// Remove the specified segment from this range. Note that the segment
+ /// must be a single Segment in its entirety.
+ void removeSegment(SlotIndex Start, SlotIndex End,
+ bool RemoveDeadValNo = false);
- void removeRange(LiveRange LR, bool RemoveDeadValNo = false) {
- removeRange(LR.start, LR.end, RemoveDeadValNo);
+ void removeSegment(Segment S, bool RemoveDeadValNo = false) {
+ removeSegment(S.start, S.end, RemoveDeadValNo);
}
- /// removeValNo - Remove all the ranges defined by the specified value#.
+ /// Query Liveness at Idx.
+ /// The sub-instruction slot of Idx doesn't matter, only the instruction
+ /// it refers to is considered.
+ LiveQueryResult Query(SlotIndex Idx) const {
+ // Find the segment that enters the instruction.
+ const_iterator I = find(Idx.getBaseIndex());
+ const_iterator E = end();
+ if (I == E)
+ return LiveQueryResult(nullptr, nullptr, SlotIndex(), false);
+
+ // Is this an instruction live-in segment?
+ // If Idx is the start index of a basic block, include live-in segments
+ // that start at Idx.getBaseIndex().
+ VNInfo *EarlyVal = nullptr;
+ VNInfo *LateVal = nullptr;
+ SlotIndex EndPoint;
+ bool Kill = false;
+ if (I->start <= Idx.getBaseIndex()) {
+ EarlyVal = I->valno;
+ EndPoint = I->end;
+ // Move to the potentially live-out segment.
+ if (SlotIndex::isSameInstr(Idx, I->end)) {
+ Kill = true;
+ if (++I == E)
+ return LiveQueryResult(EarlyVal, LateVal, EndPoint, Kill);
+ }
+ // Special case: A PHIDef value can have its def in the middle of a
+ // segment if the value happens to be live out of the layout
+ // predecessor.
+ // Such a value is not live-in.
+ if (EarlyVal->def == Idx.getBaseIndex())
+ EarlyVal = nullptr;
+ }
+ // I now points to the segment that may be live-through, or defined by
+ // this instr. Ignore segments starting after the current instr.
+ if (!SlotIndex::isEarlierInstr(Idx, I->start)) {
+ LateVal = I->valno;
+ EndPoint = I->end;
+ }
+ return LiveQueryResult(EarlyVal, LateVal, EndPoint, Kill);
+ }
+
+ /// removeValNo - Remove all the segments defined by the specified value#.
/// Also remove the value# from value# list.
void removeValNo(VNInfo *ValNo);
- /// getSize - Returns the sum of sizes of all the LiveRange's.
- ///
- unsigned getSize() const;
-
- /// Returns true if the live interval is zero length, i.e. no live ranges
- /// span instructions. It doesn't pay to spill such an interval.
+ /// Returns true if the live range is zero length, i.e. no live segments
+ /// span instructions. It doesn't pay to spill such a range.
bool isZeroLength(SlotIndexes *Indexes) const {
for (const_iterator i = begin(), e = end(); i != e; ++i)
if (Indexes->getNextNonNullIndex(i->start).getBaseIndex() <
return true;
}
- /// isSpillable - Can this interval be spilled?
- bool isSpillable() const {
- return weight != HUGE_VALF;
- }
-
- /// markNotSpillable - Mark interval as not spillable
- void markNotSpillable() {
- weight = HUGE_VALF;
- }
-
- bool operator<(const LiveInterval& other) const {
+ bool operator<(const LiveRange& other) const {
const SlotIndex &thisIndex = beginIndex();
const SlotIndex &otherIndex = other.beginIndex();
- return (thisIndex < otherIndex ||
- (thisIndex == otherIndex && reg < other.reg));
+ return thisIndex < otherIndex;
}
void print(raw_ostream &OS) const;
void dump() const;
- /// \brief Walk the interval and assert if any invariants fail to hold.
+ /// \brief Walk the range and assert if any invariants fail to hold.
///
/// Note that this is a no-op when asserts are disabled.
#ifdef NDEBUG
private:
- Ranges::iterator addRangeFrom(LiveRange LR, Ranges::iterator From);
- void extendIntervalEndTo(Ranges::iterator I, SlotIndex NewEnd);
- Ranges::iterator extendIntervalStartTo(Ranges::iterator I, SlotIndex NewStr);
+ iterator addSegmentFrom(Segment S, iterator From);
+ void extendSegmentEndTo(iterator I, SlotIndex NewEnd);
+ iterator extendSegmentStartTo(iterator I, SlotIndex NewStr);
void markValNoForDeletion(VNInfo *V);
+ };
+
+ inline raw_ostream &operator<<(raw_ostream &OS, const LiveRange &LR) {
+ LR.print(OS);
+ return OS;
+ }
+
+ /// LiveInterval - This class represents the liveness of a register,
+ /// or stack slot.
+ class LiveInterval : public LiveRange {
+ public:
+ typedef LiveRange super;
+
+ const unsigned reg; // the register or stack slot of this interval.
+ float weight; // weight of this interval
+
+ LiveInterval(unsigned Reg, float Weight)
+ : reg(Reg), weight(Weight) {}
+
+ /// getSize - Returns the sum of sizes of all the LiveRange's.
+ ///
+ unsigned getSize() const;
+
+ /// isSpillable - Can this interval be spilled?
+ bool isSpillable() const {
+ return weight != llvm::huge_valf;
+ }
+
+ /// markNotSpillable - Mark interval as not spillable
+ void markNotSpillable() {
+ weight = llvm::huge_valf;
+ }
+
+ bool operator<(const LiveInterval& other) const {
+ const SlotIndex &thisIndex = beginIndex();
+ const SlotIndex &otherIndex = other.beginIndex();
+ return std::tie(thisIndex, reg) < std::tie(otherIndex, other.reg);
+ }
+
+ void print(raw_ostream &OS) const;
+ void dump() const;
+
+ private:
LiveInterval& operator=(const LiveInterval& rhs) LLVM_DELETED_FUNCTION;
};
return OS;
}
- /// Helper class for performant LiveInterval bulk updates.
+ raw_ostream &operator<<(raw_ostream &OS, const LiveRange::Segment &S);
+
+ inline bool operator<(SlotIndex V, const LiveRange::Segment &S) {
+ return V < S.start;
+ }
+
+ inline bool operator<(const LiveRange::Segment &S, SlotIndex V) {
+ return S.start < V;
+ }
+
+ /// Helper class for performant LiveRange bulk updates.
///
- /// Calling LiveInterval::addRange() repeatedly can be expensive on large
+ /// Calling LiveRange::addSegment() repeatedly can be expensive on large
/// live ranges because segments after the insertion point may need to be
/// shifted. The LiveRangeUpdater class can defer the shifting when adding
/// many segments in order.
///
- /// The LiveInterval will be in an invalid state until flush() is called.
+ /// The LiveRange will be in an invalid state until flush() is called.
class LiveRangeUpdater {
- LiveInterval *LI;
+ LiveRange *LR;
SlotIndex LastStart;
- LiveInterval::iterator WriteI;
- LiveInterval::iterator ReadI;
- SmallVector<LiveRange, 16> Spills;
+ LiveRange::iterator WriteI;
+ LiveRange::iterator ReadI;
+ SmallVector<LiveRange::Segment, 16> Spills;
void mergeSpills();
public:
- /// Create a LiveRangeUpdater for adding segments to LI.
- /// LI will temporarily be in an invalid state until flush() is called.
- LiveRangeUpdater(LiveInterval *li = 0) : LI(li) {}
+ /// Create a LiveRangeUpdater for adding segments to LR.
+ /// LR will temporarily be in an invalid state until flush() is called.
+ LiveRangeUpdater(LiveRange *lr = nullptr) : LR(lr) {}
~LiveRangeUpdater() { flush(); }
- /// Add a segment to LI and coalesce when possible, just like LI.addRange().
- /// Segments should be added in increasing start order for best performance.
- void add(LiveRange);
+ /// Add a segment to LR and coalesce when possible, just like
+ /// LR.addSegment(). Segments should be added in increasing start order for
+ /// best performance.
+ void add(LiveRange::Segment);
void add(SlotIndex Start, SlotIndex End, VNInfo *VNI) {
- add(LiveRange(Start, End, VNI));
+ add(LiveRange::Segment(Start, End, VNI));
}
- /// Return true if the LI is currently in an invalid state, and flush()
+ /// Return true if the LR is currently in an invalid state, and flush()
/// needs to be called.
bool isDirty() const { return LastStart.isValid(); }
- /// Flush the updater state to LI so it is valid and contains all added
+ /// Flush the updater state to LR so it is valid and contains all added
/// segments.
void flush();
/// Select a different destination live range.
- void setDest(LiveInterval *li) {
- if (LI != li && isDirty())
+ void setDest(LiveRange *lr) {
+ if (LR != lr && isDirty())
flush();
- LI = li;
+ LR = lr;
}
/// Get the current destination live range.
- LiveInterval *getDest() const { return LI; }
+ LiveRange *getDest() const { return LR; }
void dump() const;
void print(raw_ostream&) const;
return OS;
}
- /// LiveRangeQuery - Query information about a live range around a given
- /// instruction. This class hides the implementation details of live ranges,
- /// and it should be used as the primary interface for examining live ranges
- /// around instructions.
- ///
- class LiveRangeQuery {
- VNInfo *EarlyVal;
- VNInfo *LateVal;
- SlotIndex EndPoint;
- bool Kill;
-
- public:
- /// Create a LiveRangeQuery for the given live range and instruction index.
- /// The sub-instruction slot of Idx doesn't matter, only the instruction it
- /// refers to is considered.
- LiveRangeQuery(const LiveInterval &LI, SlotIndex Idx)
- : EarlyVal(0), LateVal(0), Kill(false) {
- // Find the segment that enters the instruction.
- LiveInterval::const_iterator I = LI.find(Idx.getBaseIndex());
- LiveInterval::const_iterator E = LI.end();
- if (I == E)
- return;
- // Is this an instruction live-in segment?
- // If Idx is the start index of a basic block, include live-in segments
- // that start at Idx.getBaseIndex().
- if (I->start <= Idx.getBaseIndex()) {
- EarlyVal = I->valno;
- EndPoint = I->end;
- // Move to the potentially live-out segment.
- if (SlotIndex::isSameInstr(Idx, I->end)) {
- Kill = true;
- if (++I == E)
- return;
- }
- // Special case: A PHIDef value can have its def in the middle of a
- // segment if the value happens to be live out of the layout
- // predecessor.
- // Such a value is not live-in.
- if (EarlyVal->def == Idx.getBaseIndex())
- EarlyVal = 0;
- }
- // I now points to the segment that may be live-through, or defined by
- // this instr. Ignore segments starting after the current instr.
- if (SlotIndex::isEarlierInstr(Idx, I->start))
- return;
- LateVal = I->valno;
- EndPoint = I->end;
- }
-
- /// Return the value that is live-in to the instruction. This is the value
- /// that will be read by the instruction's use operands. Return NULL if no
- /// value is live-in.
- VNInfo *valueIn() const {
- return EarlyVal;
- }
-
- /// Return true if the live-in value is killed by this instruction. This
- /// means that either the live range ends at the instruction, or it changes
- /// value.
- bool isKill() const {
- return Kill;
- }
-
- /// Return true if this instruction has a dead def.
- bool isDeadDef() const {
- return EndPoint.isDead();
- }
-
- /// Return the value leaving the instruction, if any. This can be a
- /// live-through value, or a live def. A dead def returns NULL.
- VNInfo *valueOut() const {
- return isDeadDef() ? 0 : LateVal;
- }
-
- /// Return the value defined by this instruction, if any. This includes
- /// dead defs, it is the value created by the instruction's def operands.
- VNInfo *valueDefined() const {
- return EarlyVal == LateVal ? 0 : LateVal;
- }
-
- /// Return the end point of the last live range segment to interact with
- /// the instruction, if any.
- ///
- /// The end point is an invalid SlotIndex only if the live range doesn't
- /// intersect the instruction at all.
- ///
- /// The end point may be at or past the end of the instruction's basic
- /// block. That means the value was live out of the block.
- SlotIndex endPoint() const {
- return EndPoint;
- }
- };
-
/// ConnectedVNInfoEqClasses - Helper class that can divide VNInfos in a
/// LiveInterval into equivalence clases of connected components. A
/// LiveInterval that has multiple connected components can be broken into
projects / oota-llvm.git / blobdiff