/// The current spill mode, selected by reset().
ComplementSpillMode SpillMode;
- /// Parent interval values where the complement interval may be overlapping
- /// other intervals.
- SmallPtrSet<const VNInfo*, 8> OverlappedComplement;
-
typedef IntervalMap<SlotIndex, unsigned> RegAssignMap;
/// Allocator for the interval map. This will eventually be shared with
/// Idx.
RegAssignMap RegAssign;
- typedef DenseMap<std::pair<unsigned, unsigned>, VNInfo*> ValueMap;
+ typedef PointerIntPair<VNInfo*, 1> ValueForcePair;
+ typedef DenseMap<std::pair<unsigned, unsigned>, ValueForcePair> ValueMap;
/// Values - keep track of the mapping from parent values to values in the new
/// intervals. Given a pair (RegIdx, ParentVNI->id), Values contains:
///
/// 1. No entry - the value is not mapped to Edit.get(RegIdx).
- /// 2. Null - the value is mapped to multiple values in Edit.get(RegIdx).
- /// Each value is represented by a minimal live range at its def.
- /// 3. A non-null VNInfo - the value is mapped to a single new value.
+ /// 2. (Null, false) - the value is mapped to multiple values in
+ /// Edit.get(RegIdx). Each value is represented by a minimal live range at
+ /// its def. The full live range can be inferred exactly from the range
+ /// of RegIdx in RegAssign.
+ /// 3. (Null, true). As above, but the ranges in RegAssign are too large, and
+ /// the live range must be recomputed using LiveRangeCalc::extend().
+ /// 4. (VNI, false) The value is mapped to a single new value.
/// The new value has no live ranges anywhere.
ValueMap Values;
/// Return the new LI value.
VNInfo *defValue(unsigned RegIdx, const VNInfo *ParentVNI, SlotIndex Idx);
- /// markComplexMapped - Mark ParentVNI as complex mapped in RegIdx regardless
- /// of the number of defs.
- void markComplexMapped(unsigned RegIdx, const VNInfo *ParentVNI);
-
- /// markOverlappedComplement - Mark ParentVNI as being overlapped in the
- /// complement interval. The complement interval may overlap other intervals
- /// after overlapIntv has been called, or when in spill mode.
- void markOverlappedComplement(const VNInfo *ParentVNI);
-
- /// needsRecompute - Returns true if the live range of ParentVNI needs to be
- /// recomputed in RegIdx using LiveRangeCalc::extend. This is the case if
- /// the value has been rematerialized, or when back-copies have been hoisted
- /// in spill mode.
- bool needsRecompute(unsigned RegIdx, const VNInfo *ParentVNI);
+ /// forceRecompute - Force the live range of ParentVNI in RegIdx to be
+ /// recomputed by LiveRangeCalc::extend regardless of the number of defs.
+ /// This is used for values whose live range doesn't match RegAssign exactly.
+ /// They could have rematerialized, or back-copies may have been moved.
+ void forceRecompute(unsigned RegIdx, const VNInfo *ParentVNI);
/// defFromParent - Define Reg from ParentVNI at UseIdx using either
/// rematerialization or a COPY from parent. Return the new value.
/// in the vector in the complement interval.
void removeBackCopies(SmallVectorImpl<VNInfo*> &Copies);
+ /// getShallowDominator - Returns the least busy dominator of MBB that is
+ /// also dominated by DefMBB. Busy is measured by loop depth.
+ MachineBasicBlock *findShallowDominator(MachineBasicBlock *MBB,
+ MachineBasicBlock *DefMBB);
+
/// hoistCopiesForSize - Hoist back-copies to the complement interval in a
/// way that minimizes code size. This implements the SM_Size spill mode.
void hoistCopiesForSize();