+ if (Other.preference && !preference)
+ preference = Other.preference;
+}
+
+/// 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;
+ unsigned 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()->def == ~1U);
+ } else {
+ V1->def = ~1U;
+ }
+ }
+ }
+ }
+}
+
+
+/// 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(const LiveInterval &Clobbers,
+ BumpPtrAllocator &VNInfoAllocator) {
+ if (Clobbers.empty()) return;
+
+ // Find a value # to use for the clobber ranges. If there is already a value#
+ // for unknown values, use it.
+ // FIXME: Use a single sentinal number for these!
+ VNInfo *ClobberValNo = getNextValue(~0U, 0, VNInfoAllocator);
+
+ iterator IP = begin();
+ for (const_iterator I = Clobbers.begin(), E = Clobbers.end(); I != E; ++I) {
+ unsigned 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) {
+ 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) {
+ End = IP->start;
+ // If this trimmed away the whole range, ignore it.
+ if (Start == End) continue;
+ }
+
+ // Insert the clobber interval.
+ IP = addRangeFrom(LiveRange(Start, End, ClobberValNo), IP);
+ }
+}
+
+/// MergeValueNumberInto - This method is called when two value nubmers
+/// are found to be equivalent. This eliminates V1, replacing all
+/// LiveRanges 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.
+void LiveInterval::MergeValueNumberInto(VNInfo *V1, VNInfo *V2) {
+ assert(V1 != V2 && "Identical value#'s are always equivalent!");
+
+ // This code actually merges the (numerically) larger value number into the
+ // smaller value number, which is likely to allow us to compactify the value
+ // space. The only thing we have to be careful of is to preserve the
+ // instruction that defines the result value.
+
+ // Make sure V2 is smaller than V1.
+ if (V1->id < V2->id) {
+ copyValNumInfo(V1, V2);
+ std::swap(V1, V2);
+ }
+
+ // Merge V1 live ranges into V2.
+ for (iterator I = begin(); I != end(); ) {
+ iterator LR = I++;
+ if (LR->valno != V1) continue; // Not a V1 LiveRange.
+
+ // Okay, we found a V1 live range. If it had a previous, touching, V2 live
+ // range, extend it.
+ if (LR != begin()) {
+ iterator Prev = LR-1;
+ if (Prev->valno == V2 && Prev->end == LR->start) {
+ Prev->end = LR->end;
+
+ // Erase this live-range.
+ ranges.erase(LR);
+ I = Prev+1;
+ LR = Prev;
+ }
+ }
+
+ // Okay, now we have a V1 or V2 live range that is maximally merged forward.
+ // Ensure that it is a V2 live-range.
+ LR->valno = V2;
+
+ // If we can merge it into later V2 live ranges, do so now. We ignore any
+ // following V1 live ranges, as they will be merged in subsequent iterations
+ // of the loop.
+ if (I != end()) {
+ if (I->start == LR->end && I->valno == V2) {
+ LR->end = I->end;
+ ranges.erase(I);
+ I = LR+1;
+ }
+ }
+ }
+
+ // 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.back()->def == ~1U);
+ } else {
+ V1->def = ~1U;
+ }
+}
+
+void LiveInterval::Copy(const LiveInterval &RHS,
+ BumpPtrAllocator &VNInfoAllocator) {
+ ranges.clear();
+ valnos.clear();
+ preference = RHS.preference;
+ weight = RHS.weight;
+ for (unsigned i = 0, e = RHS.getNumValNums(); i != e; ++i) {
+ const VNInfo *VNI = RHS.getValNumInfo(i);
+ VNInfo *NewVNI = getNextValue(~0U, 0, VNInfoAllocator);
+ copyValNumInfo(NewVNI, VNI);
+ }
+ for (unsigned i = 0, e = RHS.ranges.size(); i != e; ++i) {
+ const LiveRange &LR = RHS.ranges[i];
+ addRange(LiveRange(LR.start, LR.end, getValNumInfo(LR.valno->id)));
+ }
+}
+
+unsigned LiveInterval::getSize() const {
+ unsigned Sum = 0;
+ for (const_iterator I = begin(), E = end(); I != E; ++I)
+ Sum += I->end - I->start;
+ return Sum;