diff options
Diffstat (limited to 'lib/CodeGen/LiveInterval.cpp')
| -rw-r--r-- | lib/CodeGen/LiveInterval.cpp | 312 |
1 files changed, 103 insertions, 209 deletions
diff --git a/lib/CodeGen/LiveInterval.cpp b/lib/CodeGen/LiveInterval.cpp index 59f380ad2641..c2dbd6ab75a1 100644 --- a/lib/CodeGen/LiveInterval.cpp +++ b/lib/CodeGen/LiveInterval.cpp @@ -30,58 +30,19 @@ #include <algorithm> using namespace llvm; -// An example for liveAt(): -// -// this = [1,4), liveAt(0) will return false. The instruction defining this -// spans slots [0,3]. The interval belongs to an spilled definition of the -// variable it represents. This is because slot 1 is used (def slot) and spans -// up to slot 3 (store slot). -// -bool LiveInterval::liveAt(SlotIndex I) const { - Ranges::const_iterator r = std::upper_bound(ranges.begin(), ranges.end(), I); - - if (r == ranges.begin()) - return false; - - --r; - return r->contains(I); -} - -// liveBeforeAndAt - Check if the interval is live at the index and the index -// just before it. If index is liveAt, check if it starts a new live range. -// If it does, then check if the previous live range ends at index-1. -bool LiveInterval::liveBeforeAndAt(SlotIndex I) const { - Ranges::const_iterator r = std::upper_bound(ranges.begin(), ranges.end(), I); - - if (r == ranges.begin()) - return false; - - --r; - if (!r->contains(I)) - return false; - if (I != r->start) - return true; - // I is the start of a live range. Check if the previous live range ends - // at I-1. - if (r == ranges.begin()) - return false; - return r->end == I; +// CompEnd - Compare LiveRange ends. +namespace { +struct CompEnd { + bool operator()(const LiveRange &A, const LiveRange &B) const { + return A.end < B.end; + } +}; } -/// killedAt - Return true if a live range ends at index. Note that the kill -/// point is not contained in the half-open live range. It is usually the -/// getDefIndex() slot following its last use. -bool LiveInterval::killedAt(SlotIndex I) const { - Ranges::const_iterator r = std::lower_bound(ranges.begin(), ranges.end(), I); - - // Now r points to the first interval with start >= I, or ranges.end(). - if (r == ranges.begin()) - return false; - - --r; - // Now r points to the last interval with end <= I. - // r->end is the kill point. - return r->end == I; +LiveInterval::iterator LiveInterval::find(SlotIndex Pos) { + assert(Pos.isValid() && "Cannot search for an invalid index"); + return std::upper_bound(begin(), end(), LiveRange(SlotIndex(), Pos, 0), + CompEnd()); } /// killedInRange - Return true if the interval has kills in [Start,End). @@ -330,25 +291,14 @@ LiveInterval::addRangeFrom(LiveRange LR, iterator From) { return ranges.insert(it, LR); } -/// isInOneLiveRange - Return true if the range specified is entirely in -/// a single LiveRange of the live interval. -bool LiveInterval::isInOneLiveRange(SlotIndex Start, SlotIndex End) { - Ranges::iterator I = std::upper_bound(ranges.begin(), ranges.end(), Start); - if (I == ranges.begin()) - return false; - --I; - return I->containsRange(Start, End); -} - /// removeRange - Remove the specified range from this interval. Note that /// the range must be in a single LiveRange in its entirety. void LiveInterval::removeRange(SlotIndex Start, SlotIndex End, bool RemoveDeadValNo) { // Find the LiveRange containing this span. - Ranges::iterator I = std::upper_bound(ranges.begin(), ranges.end(), Start); - assert(I != ranges.begin() && "Range is not in interval!"); - --I; + Ranges::iterator I = find(Start); + assert(I != ranges.end() && "Range is not in interval!"); assert(I->containsRange(Start, End) && "Range is not entirely in interval!"); // If the span we are removing is at the start of the LiveRange, adjust it. @@ -405,32 +355,6 @@ void LiveInterval::removeValNo(VNInfo *ValNo) { markValNoForDeletion(ValNo); } -/// getLiveRangeContaining - Return the live range that contains the -/// specified index, or null if there is none. -LiveInterval::const_iterator -LiveInterval::FindLiveRangeContaining(SlotIndex Idx) const { - const_iterator It = std::upper_bound(begin(), end(), Idx); - if (It != ranges.begin()) { - --It; - if (It->contains(Idx)) - return It; - } - - return end(); -} - -LiveInterval::iterator -LiveInterval::FindLiveRangeContaining(SlotIndex Idx) { - iterator It = std::upper_bound(begin(), end(), Idx); - if (It != begin()) { - --It; - if (It->contains(Idx)) - return It; - } - - return end(); -} - /// findDefinedVNInfo - Find the VNInfo defined by the specified /// index (register interval). VNInfo *LiveInterval::findDefinedVNInfoForRegInt(SlotIndex Idx) const { @@ -443,17 +367,6 @@ VNInfo *LiveInterval::findDefinedVNInfoForRegInt(SlotIndex Idx) const { return 0; } -/// findDefinedVNInfo - Find the VNInfo defined by the specified -/// register (stack inteval). -VNInfo *LiveInterval::findDefinedVNInfoForStackInt(unsigned reg) const { - for (LiveInterval::const_vni_iterator i = vni_begin(), e = vni_end(); - i != e; ++i) { - if ((*i)->getReg() == reg) - return *i; - } - return 0; -} - /// 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. @@ -616,103 +529,6 @@ void LiveInterval::MergeValueInAsValue( } -/// 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, - VNInfo::Allocator &VNInfoAllocator) { - if (Clobbers.empty()) return; - - DenseMap<VNInfo*, VNInfo*> ValNoMaps; - VNInfo *UnusedValNo = 0; - iterator IP = begin(); - for (const_iterator I = Clobbers.begin(), E = Clobbers.end(); I != E; ++I) { - // For every val# in the Clobbers interval, create a new "unknown" val#. - VNInfo *ClobberValNo = 0; - DenseMap<VNInfo*, VNInfo*>::iterator VI = ValNoMaps.find(I->valno); - if (VI != ValNoMaps.end()) - ClobberValNo = VI->second; - else if (UnusedValNo) - ClobberValNo = UnusedValNo; - else { - UnusedValNo = ClobberValNo = - getNextValue(li_.getInvalidIndex(), 0, false, VNInfoAllocator); - ValNoMaps.insert(std::make_pair(I->valno, ClobberValNo)); - } - - bool Done = false; - SlotIndex Start = I->start, End = I->end; - // If a clobber range starts before an existing range and ends after - // it, the clobber range will need to be split into multiple ranges. - // Loop until the entire clobber range is handled. - while (!Done) { - Done = true; - IP = std::upper_bound(IP, end(), Start); - SlotIndex SubRangeStart = Start; - SlotIndex SubRangeEnd = End; - - // If the start of this range overlaps with an existing liverange, trim it. - if (IP != begin() && IP[-1].end > SubRangeStart) { - SubRangeStart = IP[-1].end; - // Trimmed away the whole range? - if (SubRangeStart >= SubRangeEnd) continue; - } - // If the end of this range overlaps with an existing liverange, trim it. - if (IP != end() && SubRangeEnd > IP->start) { - // If the clobber live range extends beyond the existing live range, - // it'll need at least another live range, so set the flag to keep - // iterating. - if (SubRangeEnd > IP->end) { - Start = IP->end; - Done = false; - } - SubRangeEnd = IP->start; - // If this trimmed away the whole range, ignore it. - if (SubRangeStart == SubRangeEnd) continue; - } - - // Insert the clobber interval. - IP = addRangeFrom(LiveRange(SubRangeStart, SubRangeEnd, ClobberValNo), - IP); - UnusedValNo = 0; - } - } - - if (UnusedValNo) { - // Delete the last unused val#. - valnos.pop_back(); - } -} - -void LiveInterval::MergeInClobberRange(LiveIntervals &li_, - SlotIndex Start, - SlotIndex End, - VNInfo::Allocator &VNInfoAllocator) { - // Find a value # to use for the clobber ranges. If there is already a value# - // for unknown values, use it. - VNInfo *ClobberValNo = - getNextValue(li_.getInvalidIndex(), 0, false, VNInfoAllocator); - - iterator IP = begin(); - 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) return; - } - // 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) return; - } - - // Insert the clobber interval. - 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 @@ -767,6 +583,9 @@ VNInfo* LiveInterval::MergeValueNumberInto(VNInfo *V1, VNInfo *V2) { } } + // Merge the relevant flags. + V2->mergeFlags(V1); + // Now that V1 is dead, remove it. markValNoForDeletion(V1); @@ -831,14 +650,9 @@ void LiveRange::dump() const { } void LiveInterval::print(raw_ostream &OS, const TargetRegisterInfo *TRI) const { - if (isStackSlot()) - OS << "SS#" << getStackSlotIndex(); - else if (TRI && TargetRegisterInfo::isPhysicalRegister(reg)) - OS << TRI->getName(reg); - else - OS << "%reg" << reg; - - OS << ',' << weight; + OS << PrintReg(reg, TRI); + if (weight != 0) + OS << ',' << weight; if (empty()) OS << " EMPTY"; @@ -863,10 +677,9 @@ void LiveInterval::print(raw_ostream &OS, const TargetRegisterInfo *TRI) const { if (vni->isUnused()) { OS << "x"; } else { - if (!vni->isDefAccurate() && !vni->isPHIDef()) - OS << "?"; - else - OS << vni->def; + OS << vni->def; + if (vni->isPHIDef()) + OS << "-phidef"; if (vni->hasPHIKill()) OS << "-phikill"; if (vni->hasRedefByEC()) @@ -884,3 +697,84 @@ void LiveInterval::dump() const { void LiveRange::print(raw_ostream &os) const { os << *this; } + +unsigned ConnectedVNInfoEqClasses::Classify(const LiveInterval *LI) { + // Create initial equivalence classes. + eqClass_.clear(); + eqClass_.grow(LI->getNumValNums()); + + const VNInfo *used = 0, *unused = 0; + + // Determine connections. + for (LiveInterval::const_vni_iterator I = LI->vni_begin(), E = LI->vni_end(); + I != E; ++I) { + const VNInfo *VNI = *I; + // Group all unused values into one class. + if (VNI->isUnused()) { + if (unused) + eqClass_.join(unused->id, VNI->id); + unused = VNI; + continue; + } + used = VNI; + if (VNI->isPHIDef()) { + const MachineBasicBlock *MBB = lis_.getMBBFromIndex(VNI->def); + assert(MBB && "Phi-def has no defining MBB"); + // Connect to values live out of predecessors. + for (MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), + PE = MBB->pred_end(); PI != PE; ++PI) + if (const VNInfo *PVNI = + LI->getVNInfoAt(lis_.getMBBEndIdx(*PI).getPrevSlot())) + eqClass_.join(VNI->id, PVNI->id); + } else { + // Normal value defined by an instruction. Check for two-addr redef. + // FIXME: This could be coincidental. Should we really check for a tied + // operand constraint? + // Note that VNI->def may be a use slot for an early clobber def. + if (const VNInfo *UVNI = LI->getVNInfoAt(VNI->def.getPrevSlot())) + eqClass_.join(VNI->id, UVNI->id); + } + } + + // Lump all the unused values in with the last used value. + if (used && unused) + eqClass_.join(used->id, unused->id); + + eqClass_.compress(); + return eqClass_.getNumClasses(); +} + +void ConnectedVNInfoEqClasses::Distribute(LiveInterval *LIV[]) { + assert(LIV[0] && "LIV[0] must be set"); + LiveInterval &LI = *LIV[0]; + + // First move runs to new intervals. + LiveInterval::iterator J = LI.begin(), E = LI.end(); + while (J != E && eqClass_[J->valno->id] == 0) + ++J; + for (LiveInterval::iterator I = J; I != E; ++I) { + if (unsigned eq = eqClass_[I->valno->id]) { + assert((LIV[eq]->empty() || LIV[eq]->expiredAt(I->start)) && + "New intervals should be empty"); + LIV[eq]->ranges.push_back(*I); + } else + *J++ = *I; + } + LI.ranges.erase(J, E); + + // Transfer VNInfos to their new owners and renumber them. + unsigned j = 0, e = LI.getNumValNums(); + while (j != e && eqClass_[j] == 0) + ++j; + for (unsigned i = j; i != e; ++i) { + VNInfo *VNI = LI.getValNumInfo(i); + if (unsigned eq = eqClass_[i]) { + VNI->id = LIV[eq]->getNumValNums(); + LIV[eq]->valnos.push_back(VNI); + } else { + VNI->id = j; + LI.valnos[j++] = VNI; + } + } + LI.valnos.resize(j); +} |