+
+ ComputeJoinedWeight(Other);
+
+ // Update regalloc hint if currently there isn't one.
+ if (TargetRegisterInfo::isVirtualRegister(reg) &&
+ TargetRegisterInfo::isVirtualRegister(Other.reg)) {
+ std::pair<unsigned, unsigned> Hint = MRI->getRegAllocationHint(reg);
+ if (Hint.first == 0 && Hint.second == 0) {
+ std::pair<unsigned, unsigned> OtherHint =
+ MRI->getRegAllocationHint(Other.reg);
+ if (OtherHint.first || OtherHint.second)
+ MRI->setRegAllocationHint(reg, OtherHint.first, OtherHint.second);
+ }
+ }
+}
+
+/// MergeRangesInAsValue - Merge all of the intervals 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 specified value number.
+void LiveInterval::MergeRangesInAsValue(const LiveInterval &RHS,
+ VNInfo *LHSValNo) {
+ // TODO: Make this more efficient.
+ iterator InsertPos = begin();
+ for (const_iterator I = RHS.begin(), E = RHS.end(); I != E; ++I) {
+ // Map the valno in the other live range to the current live range.
+ LiveRange Tmp = *I;
+ Tmp.valno = LHSValNo;
+ InsertPos = addRangeFrom(Tmp, InsertPos);
+ }
+}
+
+
+/// 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 LiveInterval::MergeValueInAsValue(
+ const LiveInterval &RHS,
+ const VNInfo *RHSValNo, VNInfo *LHSValNo) {
+ SmallVector<VNInfo*, 4> ReplacedValNos;
+ iterator IP = begin();
+ for (const_iterator I = RHS.begin(), E = RHS.end(); I != E; ++I) {
+ if (I->valno != RHSValNo)
+ continue;
+ SlotIndex Start = I->start, End = I->end;
+ IP = std::upper_bound(IP, end(), Start);
+ // If the start of this range overlaps with an existing liverange, trim it.
+ if (IP != begin() && IP[-1].end > Start) {
+ if (IP[-1].valno != LHSValNo) {
+ ReplacedValNos.push_back(IP[-1].valno);
+ IP[-1].valno = LHSValNo; // Update val#.
+ }
+ Start = IP[-1].end;
+ // Trimmed away the whole range?
+ if (Start >= End) continue;
+ }
+ // If the end of this range overlaps with an existing liverange, trim it.
+ if (IP != end() && End > IP->start) {
+ if (IP->valno != LHSValNo) {
+ ReplacedValNos.push_back(IP->valno);
+ IP->valno = LHSValNo; // Update val#.
+ }
+ End = IP->start;
+ // If this trimmed away the whole range, ignore it.
+ if (Start == End) continue;
+ }
+
+ // Map the valno in the other live range to the current live range.
+ IP = addRangeFrom(LiveRange(Start, End, LHSValNo), IP);
+ }
+
+
+ SmallSet<VNInfo*, 4> Seen;
+ for (unsigned i = 0, e = ReplacedValNos.size(); i != e; ++i) {
+ VNInfo *V1 = ReplacedValNos[i];
+ if (Seen.insert(V1)) {
+ bool isDead = true;
+ for (const_iterator I = begin(), E = end(); I != E; ++I)
+ if (I->valno == V1) {
+ isDead = false;
+ break;
+ }
+ if (isDead) {
+ // Now that V1 is dead, remove it. If it is the largest value number,
+ // just nuke it (and any other deleted values neighboring it), otherwise
+ // mark it as ~1U so it can be nuked later.
+ if (V1->id == getNumValNums()-1) {
+ do {
+ VNInfo *VNI = valnos.back();
+ valnos.pop_back();
+ VNI->~VNInfo();
+ } while (!valnos.empty() && valnos.back()->isUnused());
+ } else {
+ V1->setIsUnused(true);
+ }
+ }
+ }
+ }
+}
+
+
+/// MergeInClobberRanges - For any live ranges that are not defined in the
+/// current interval, but are defined in the Clobbers interval, mark them
+/// used with an unknown definition value.
+void LiveInterval::MergeInClobberRanges(LiveIntervals &li_,
+ const LiveInterval &Clobbers,
+ BumpPtrAllocator &VNInfoAllocator) {
+ if (Clobbers.empty()) return;