namespace llvm {
+class MachineLoopRange;
+class TargetRegisterInfo;
+
#ifndef NDEBUG
// forward declaration
template <unsigned Element> class SparseBitVector;
typedef SparseBitVector<128> LiveVirtRegBitSet;
#endif
-/// Abstraction to provide info for the representative register.
-class AbstractRegisterDescription {
-public:
- virtual const char *getName(unsigned Reg) const = 0;
- virtual ~AbstractRegisterDescription() {}
-};
-
/// Compare a live virtual register segment to a LiveIntervalUnion segment.
inline bool
overlap(const LiveRange &VRSeg,
// LiveIntervalUnions share an external allocator.
typedef LiveSegments::Allocator Allocator;
- class InterferenceResult;
class Query;
private:
const unsigned RepReg; // representative register number
+ unsigned Tag; // unique tag for current contents.
LiveSegments Segments; // union of virtual reg segments
public:
- LiveIntervalUnion(unsigned r, Allocator &a) : RepReg(r), Segments(a) {}
+ LiveIntervalUnion(unsigned r, Allocator &a) : RepReg(r), Tag(0), Segments(a)
+ {}
// Iterate over all segments in the union of live virtual registers ordered
// by their starting position.
SegmentIter begin() { return Segments.begin(); }
SegmentIter end() { return Segments.end(); }
SegmentIter find(SlotIndex x) { return Segments.find(x); }
- bool empty() { return Segments.empty(); }
- SlotIndex startIndex() { return Segments.start(); }
+ bool empty() const { return Segments.empty(); }
+ SlotIndex startIndex() const { return Segments.start(); }
+
+ // Provide public access to the underlying map to allow overlap iteration.
+ typedef LiveSegments Map;
+ const Map &getMap() { return Segments; }
+
+ /// getTag - Return an opaque tag representing the current state of the union.
+ unsigned getTag() const { return Tag; }
+
+ /// changedSince - Return true if the union change since getTag returned tag.
+ bool changedSince(unsigned tag) const { return tag != Tag; }
// Add a live virtual register to this union and merge its segments.
void unify(LiveInterval &VirtReg);
// Remove a live virtual register's segments from this union.
void extract(LiveInterval &VirtReg);
- void dump(const AbstractRegisterDescription *RegDesc) const;
+ // Remove all inserted virtual registers.
+ void clear() { Segments.clear(); ++Tag; }
- // If tri != NULL, use it to decode RepReg
- void print(raw_ostream &OS, const AbstractRegisterDescription *RegDesc) const;
+ // Print union, using TRI to translate register names
+ void print(raw_ostream &OS, const TargetRegisterInfo *TRI) const;
#ifndef NDEBUG
// Verify the live intervals in this union and add them to the visited set.
void verify(LiveVirtRegBitSet& VisitedVRegs);
#endif
- /// Cache a single interference test result in the form of two intersecting
- /// segments. This allows efficiently iterating over the interferences. The
- /// iteration logic is handled by LiveIntervalUnion::Query which may
- /// filter interferences depending on the type of query.
- class InterferenceResult {
- friend class Query;
-
- LiveInterval::iterator VirtRegI; // current position in VirtReg
- SegmentIter LiveUnionI; // current position in LiveUnion
-
- // Internal ctor.
- InterferenceResult(LiveInterval::iterator VRegI, SegmentIter UnionI)
- : VirtRegI(VRegI), LiveUnionI(UnionI) {}
-
- public:
- // Public default ctor.
- InterferenceResult(): VirtRegI(), LiveUnionI() {}
-
- // Note: this interface provides raw access to the iterators because the
- // result has no way to tell if it's valid to dereference them.
-
- // Access the VirtReg segment.
- LiveInterval::iterator virtRegPos() const { return VirtRegI; }
-
- // Access the LiveUnion segment.
- const SegmentIter &liveUnionPos() const { return LiveUnionI; }
-
- bool operator==(const InterferenceResult &IR) const {
- return VirtRegI == IR.VirtRegI && LiveUnionI == IR.LiveUnionI;
- }
- bool operator!=(const InterferenceResult &IR) const {
- return !operator==(IR);
- }
- };
-
/// Query interferences between a single live virtual register and a live
/// interval union.
class Query {
LiveIntervalUnion *LiveUnion;
LiveInterval *VirtReg;
- InterferenceResult FirstInterference;
+ LiveInterval::iterator VirtRegI; // current position in VirtReg
+ SegmentIter LiveUnionI; // current position in LiveUnion
SmallVector<LiveInterval*,4> InterferingVRegs;
bool CheckedFirstInterference;
bool SeenAllInterferences;
bool SeenUnspillableVReg;
+ unsigned Tag, UserTag;
public:
- Query(): LiveUnion(), VirtReg() {}
+ Query(): LiveUnion(), VirtReg(), Tag(0), UserTag(0) {}
Query(LiveInterval *VReg, LiveIntervalUnion *LIU):
- LiveUnion(LIU), VirtReg(VReg), SeenAllInterferences(false),
- SeenUnspillableVReg(false)
+ LiveUnion(LIU), VirtReg(VReg), CheckedFirstInterference(false),
+ SeenAllInterferences(false), SeenUnspillableVReg(false)
{}
void clear() {
CheckedFirstInterference = false;
SeenAllInterferences = false;
SeenUnspillableVReg = false;
+ Tag = 0;
+ UserTag = 0;
}
- void init(LiveInterval *VReg, LiveIntervalUnion *LIU) {
- if (VirtReg == VReg && LiveUnion == LIU) {
+ void init(unsigned UTag, LiveInterval *VReg, LiveIntervalUnion *LIU) {
+ assert(VReg && LIU && "Invalid arguments");
+ if (UserTag == UTag && VirtReg == VReg &&
+ LiveUnion == LIU && !LIU->changedSince(Tag)) {
// Retain cached results, e.g. firstInterference.
return;
}
clear();
LiveUnion = LIU;
VirtReg = VReg;
+ Tag = LIU->getTag();
+ UserTag = UTag;
}
LiveInterval &virtReg() const {
return *VirtReg;
}
- bool isInterference(const InterferenceResult &IR) const {
- if (IR.VirtRegI != VirtReg->end()) {
- assert(overlap(*IR.VirtRegI, IR.LiveUnionI) &&
- "invalid segment iterators");
- return true;
- }
- return false;
- }
-
// Does this live virtual register interfere with the union?
- bool checkInterference() { return isInterference(firstInterference()); }
-
- // Get the first pair of interfering segments, or a noninterfering result.
- // This initializes the firstInterference_ cache.
- const InterferenceResult &firstInterference();
-
- // Treat the result as an iterator and advance to the next interfering pair
- // of segments. Visiting each unique interfering pairs means that the same
- // VirtReg or LiveUnion segment may be visited multiple times.
- bool nextInterference(InterferenceResult &IR) const;
+ bool checkInterference() { return collectInterferingVRegs(1); }
// Count the virtual registers in this union that interfere with this
// query's live virtual register, up to maxInterferingRegs.
return InterferingVRegs;
}
+ /// checkLoopInterference - Return true if there is interference overlapping
+ /// Loop.
+ bool checkLoopInterference(MachineLoopRange*);
+
private:
Query(const Query&); // DO NOT IMPLEMENT
void operator=(const Query&); // DO NOT IMPLEMENT
-
- // Private interface for queries
- void findIntersection(InterferenceResult &IR) const;
};
};