X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FLiveInterval.cpp;h=40f8cd4388d89bc65bc89358e06d8d74e4b481e0;hb=b0000c376cf13ed63306622ab9642cfae49f074a;hp=174b4830d01180068c65ad5ce4032389dfba4960;hpb=c4d3b918165461bc6f5d395bca8d9d9d8a84413d;p=oota-llvm.git diff --git a/lib/CodeGen/LiveInterval.cpp b/lib/CodeGen/LiveInterval.cpp index 174b4830d01..40f8cd4388d 100644 --- a/lib/CodeGen/LiveInterval.cpp +++ b/lib/CodeGen/LiveInterval.cpp @@ -2,8 +2,8 @@ // // The LLVM Compiler Infrastructure // -// This file was developed by the LLVM research group and is distributed under -// the University of Illinois Open Source License. See LICENSE.TXT for details. +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // @@ -18,11 +18,13 @@ // //===----------------------------------------------------------------------===// -#include "LiveInterval.h" +#include "llvm/CodeGen/LiveInterval.h" +#include "llvm/ADT/SmallSet.h" #include "llvm/ADT/STLExtras.h" +#include "llvm/Support/Streams.h" +#include "llvm/Target/TargetRegisterInfo.h" #include -#include -#include +#include using namespace llvm; // An example for liveAt(): @@ -34,7 +36,7 @@ using namespace llvm; // bool LiveInterval::liveAt(unsigned I) const { Ranges::const_iterator r = std::upper_bound(ranges.begin(), ranges.end(), I); - + if (r == ranges.begin()) return false; @@ -42,6 +44,30 @@ bool LiveInterval::liveAt(unsigned I) const { 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(unsigned 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; +} + +// overlaps - Return true if the intersection of the two live intervals is +// not empty. +// // An example for overlaps(): // // 0: A = ... @@ -56,31 +82,38 @@ bool LiveInterval::liveAt(unsigned I) const { // // A->overlaps(C) should return false since we want to be able to join // A and C. -bool LiveInterval::overlaps(const LiveInterval& other) const { - Ranges::const_iterator i = ranges.begin(); - Ranges::const_iterator ie = ranges.end(); - Ranges::const_iterator j = other.ranges.begin(); - Ranges::const_iterator je = other.ranges.end(); +// +bool LiveInterval::overlapsFrom(const LiveInterval& other, + const_iterator StartPos) const { + const_iterator i = begin(); + const_iterator ie = end(); + const_iterator j = StartPos; + const_iterator je = other.end(); + + assert((StartPos->start <= i->start || StartPos == other.begin()) && + StartPos != other.end() && "Bogus start position hint!"); if (i->start < j->start) { i = std::upper_bound(i, ie, j->start); if (i != ranges.begin()) --i; } else if (j->start < i->start) { - j = std::upper_bound(j, je, i->start); - if (j != other.ranges.begin()) --j; + ++StartPos; + if (StartPos != other.end() && StartPos->start <= i->start) { + assert(StartPos < other.end() && i < end()); + j = std::upper_bound(j, je, i->start); + if (j != other.ranges.begin()) --j; + } } else { return true; } - while (i != ie && j != je) { - if (i->start == j->start) - return true; + if (j == je) return false; + while (i != ie) { if (i->start > j->start) { std::swap(i, j); std::swap(ie, je); } - assert(i->start < j->start); if (i->end > j->start) return true; @@ -90,84 +123,47 @@ bool LiveInterval::overlaps(const LiveInterval& other) const { return false; } -/// joinable - Two intervals are joinable if the either don't overlap at all -/// or if the destination of the copy is a single assignment value, and it -/// only overlaps with one value in the source interval. -bool LiveInterval::joinable(const LiveInterval &other, unsigned CopyIdx) const { - const LiveRange *SourceLR = other.getLiveRangeContaining(CopyIdx-1); - const LiveRange *DestLR = getLiveRangeContaining(CopyIdx); - assert(SourceLR && DestLR && "Not joining due to a copy?"); - unsigned OtherValIdx = SourceLR->ValId; - unsigned ThisValIdx = DestLR->ValId; - - Ranges::const_iterator i = ranges.begin(); - Ranges::const_iterator ie = ranges.end(); - Ranges::const_iterator j = other.ranges.begin(); - Ranges::const_iterator je = other.ranges.end(); - - if (i->start < j->start) { - i = std::upper_bound(i, ie, j->start); - if (i != ranges.begin()) --i; - } else if (j->start < i->start) { - j = std::upper_bound(j, je, i->start); - if (j != other.ranges.begin()) --j; - } - - while (i != ie && j != je) { - if (i->start == j->start) { - // If this is not the allowed value merge, we cannot join. - if (i->ValId != ThisValIdx || j->ValId != OtherValIdx) - return false; - } else if (i->start < j->start) { - if (i->end > j->start) { - if (i->ValId != ThisValIdx || j->ValId != OtherValIdx) - return false; - } - } else { - if (j->end > i->start) { - if (i->ValId != ThisValIdx || j->ValId != OtherValIdx) - return false; - } - } - if (i->end < j->end) - ++i; - else - ++j; - } - - return true; -} - - /// extendIntervalEndTo - This method is used when we want to extend the range /// specified by I to end at the specified endpoint. To do this, we should /// merge and eliminate all ranges that this will overlap with. The iterator is /// not invalidated. void LiveInterval::extendIntervalEndTo(Ranges::iterator I, unsigned NewEnd) { assert(I != ranges.end() && "Not a valid interval!"); - unsigned ValId = I->ValId; + VNInfo *ValNo = I->valno; + unsigned OldEnd = I->end; // Search for the first interval that we can't merge with. Ranges::iterator MergeTo = next(I); for (; MergeTo != ranges.end() && NewEnd >= MergeTo->end; ++MergeTo) { - assert(MergeTo->ValId == ValId && "Cannot merge with differing values!"); + assert(MergeTo->valno == ValNo && "Cannot merge with differing values!"); } // If NewEnd was in the middle of an interval, make sure to get its endpoint. I->end = std::max(NewEnd, prior(MergeTo)->end); - // Erase any dead ranges + // Erase any dead ranges. ranges.erase(next(I), MergeTo); + + // Update kill info. + removeKills(ValNo, OldEnd, I->end-1); + + // If the newly formed range now touches the range after it and if they have + // the same value number, merge the two ranges into one range. + Ranges::iterator Next = next(I); + if (Next != ranges.end() && Next->start <= I->end && Next->valno == ValNo) { + I->end = Next->end; + ranges.erase(Next); + } } /// extendIntervalStartTo - This method is used when we want to extend the range /// specified by I to start at the specified endpoint. To do this, we should /// merge and eliminate all ranges that this will overlap with. -LiveInterval::Ranges::iterator +LiveInterval::Ranges::iterator LiveInterval::extendIntervalStartTo(Ranges::iterator I, unsigned NewStart) { assert(I != ranges.end() && "Not a valid interval!"); - unsigned ValId = I->ValId; + VNInfo *ValNo = I->valno; // Search for the first interval that we can't merge with. Ranges::iterator MergeTo = I; @@ -177,13 +173,13 @@ LiveInterval::extendIntervalStartTo(Ranges::iterator I, unsigned NewStart) { ranges.erase(MergeTo, I); return I; } - assert(MergeTo->ValId == ValId && "Cannot merge with differing values!"); + assert(MergeTo->valno == ValNo && "Cannot merge with differing values!"); --MergeTo; } while (NewStart <= MergeTo->start); // If we start in the middle of another interval, just delete a range and // extend that interval. - if (MergeTo->end >= NewStart && MergeTo->ValId == ValId) { + if (MergeTo->end >= NewStart && MergeTo->valno == ValNo) { MergeTo->end = I->end; } else { // Otherwise, extend the interval right after. @@ -196,32 +192,33 @@ LiveInterval::extendIntervalStartTo(Ranges::iterator I, unsigned NewStart) { return MergeTo; } -LiveInterval::Ranges::iterator -LiveInterval::addRangeFrom(LiveRange LR, Ranges::iterator From) { +LiveInterval::iterator +LiveInterval::addRangeFrom(LiveRange LR, iterator From) { unsigned Start = LR.start, End = LR.end; - Ranges::iterator it = std::upper_bound(From, ranges.end(), Start); + iterator it = std::upper_bound(From, ranges.end(), Start); // If the inserted interval starts in the middle or right at the end of // another interval, just extend that interval to contain the range of LR. if (it != ranges.begin()) { - Ranges::iterator B = prior(it); - if (LR.ValId == B->ValId) { + iterator B = prior(it); + if (LR.valno == B->valno) { if (B->start <= Start && B->end >= Start) { extendIntervalEndTo(B, End); return B; } } else { // Check to make sure that we are not overlapping two live ranges with - // different ValId's. + // different valno's. assert(B->end <= Start && - "Cannot overlap two LiveRanges with differing ValID's"); + "Cannot overlap two LiveRanges with differing ValID's" + " (did you def the same reg twice in a MachineInstr?)"); } } // Otherwise, if this range ends in the middle of, or right next to, another // interval, merge it into that interval. - if (it != ranges.end()) - if (LR.ValId == it->ValId) { + if (it != ranges.end()) { + if (LR.valno == it->valno) { if (it->start <= End) { it = extendIntervalStartTo(it, Start); @@ -229,24 +226,39 @@ LiveInterval::addRangeFrom(LiveRange LR, Ranges::iterator From) { // endpoint as well. if (End > it->end) extendIntervalEndTo(it, End); + else if (End < it->end) + // Overlapping intervals, there might have been a kill here. + removeKill(it->valno, End); return it; } } else { // Check to make sure that we are not overlapping two live ranges with - // different ValId's. + // different valno's. assert(it->start >= End && "Cannot overlap two LiveRanges with differing ValID's"); } + } // Otherwise, this is just a new range that doesn't interact with anything. // Insert it. return ranges.insert(it, LR); } +/// isInOneLiveRange - Return true if the range specified is entirely in the +/// a single LiveRange of the live interval. +bool LiveInterval::isInOneLiveRange(unsigned Start, unsigned End) { + Ranges::iterator I = std::upper_bound(ranges.begin(), ranges.end(), Start); + if (I == ranges.begin()) + return false; + --I; + return I->contains(Start) && I->contains(End-1); +} + /// removeRange - Remove the specified range from this interval. Note that -/// the range must already be in this interval in its entirety. -void LiveInterval::removeRange(unsigned Start, unsigned End) { +/// the range must be in a single LiveRange in its entirety. +void LiveInterval::removeRange(unsigned Start, unsigned 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!"); @@ -255,10 +267,36 @@ void LiveInterval::removeRange(unsigned Start, unsigned End) { "Range is not entirely in interval!"); // If the span we are removing is at the start of the LiveRange, adjust it. + VNInfo *ValNo = I->valno; if (I->start == Start) { - if (I->end == End) + if (I->end == End) { + removeKills(I->valno, Start, End); + if (RemoveDeadValNo) { + // Check if val# is dead. + bool isDead = true; + for (const_iterator II = begin(), EE = end(); II != EE; ++II) + if (II != I && II->valno == ValNo) { + isDead = false; + break; + } + if (isDead) { + // Now that ValNo 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 (ValNo->id == getNumValNums()-1) { + do { + VNInfo *VNI = valnos.back(); + valnos.pop_back(); + VNI->~VNInfo(); + } while (!valnos.empty() && valnos.back()->def == ~1U); + } else { + ValNo->def = ~1U; + } + } + } + ranges.erase(I); // Removed the whole LiveRange. - else + } else I->start = End; return; } @@ -266,6 +304,7 @@ void LiveInterval::removeRange(unsigned Start, unsigned End) { // Otherwise if the span we are removing is at the end of the LiveRange, // adjust the other way. if (I->end == End) { + removeKills(ValNo, Start, End); I->end = Start; return; } @@ -275,84 +314,441 @@ void LiveInterval::removeRange(unsigned Start, unsigned End) { I->end = Start; // Trim the old interval. // Insert the new one. - ranges.insert(next(I), LiveRange(End, OldEnd, I->ValId)); + ranges.insert(next(I), LiveRange(End, OldEnd, ValNo)); } +/// removeValNo - Remove all the ranges defined by the specified value#. +/// Also remove the value# from value# list. +void LiveInterval::removeValNo(VNInfo *ValNo) { + if (empty()) return; + Ranges::iterator I = ranges.end(); + Ranges::iterator E = ranges.begin(); + do { + --I; + if (I->valno == ValNo) + ranges.erase(I); + } while (I != E); + // Now that ValNo 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 (ValNo->id == getNumValNums()-1) { + do { + VNInfo *VNI = valnos.back(); + valnos.pop_back(); + VNI->~VNInfo(); + } while (!valnos.empty() && valnos.back()->def == ~1U); + } else { + ValNo->def = ~1U; + } +} + /// getLiveRangeContaining - Return the live range that contains the /// specified index, or null if there is none. -const LiveRange *LiveInterval::getLiveRangeContaining(unsigned Idx) const { - Ranges::const_iterator It = std::upper_bound(ranges.begin(),ranges.end(),Idx); +LiveInterval::const_iterator +LiveInterval::FindLiveRangeContaining(unsigned Idx) const { + const_iterator It = std::upper_bound(begin(), end(), Idx); if (It != ranges.begin()) { - const LiveRange &LR = *prior(It); - if (LR.contains(Idx)) - return &LR; + --It; + if (It->contains(Idx)) + return It; } - return 0; + return end(); +} + +LiveInterval::iterator +LiveInterval::FindLiveRangeContaining(unsigned 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 that's defined at the specified index +/// (register interval) or defined by the specified register (stack inteval). +VNInfo *LiveInterval::findDefinedVNInfo(unsigned DefIdxOrReg) const { + VNInfo *VNI = NULL; + for (LiveInterval::const_vni_iterator i = vni_begin(), e = vni_end(); + i != e; ++i) + if ((*i)->def == DefIdxOrReg) { + VNI = *i; + break; + } + return VNI; +} -/// join - Join two live intervals (this, and other) together. This operation -/// is the result of a copy instruction in the source program, that occurs at -/// index 'CopyIdx' that copies from 'Other' to 'this'. -void LiveInterval::join(LiveInterval &Other, unsigned CopyIdx) { - const LiveRange *SourceLR = Other.getLiveRangeContaining(CopyIdx-1); - const LiveRange *DestLR = getLiveRangeContaining(CopyIdx); - assert(SourceLR && DestLR && "Not joining due to a copy?"); - unsigned MergedSrcValIdx = SourceLR->ValId; - unsigned MergedDstValIdx = DestLR->ValId; - - // Try to do the least amount of work possible. In particular, if there are - // more liverange chunks in the other set than there are in the 'this' set, - // swap sets to merge the fewest chunks in possible. - if (Other.ranges.size() > ranges.size()) { - std::swap(MergedSrcValIdx, MergedDstValIdx); - std::swap(ranges, Other.ranges); - std::swap(NumValues, Other.NumValues); +/// 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. +void LiveInterval::join(LiveInterval &Other, const int *LHSValNoAssignments, + const int *RHSValNoAssignments, + SmallVector &NewVNInfo) { + // Determine if any of our live range values are mapped. This is uncommon, so + // we want to avoid the interval scan if not. + bool MustMapCurValNos = false; + unsigned NumVals = getNumValNums(); + unsigned NumNewVals = NewVNInfo.size(); + for (unsigned i = 0; i != NumVals; ++i) { + unsigned LHSValID = LHSValNoAssignments[i]; + if (i != LHSValID || + (NewVNInfo[LHSValID] && NewVNInfo[LHSValID] != getValNumInfo(i))) + MustMapCurValNos = true; } - // Join the ranges of other into the ranges of this interval. - Ranges::iterator InsertPos = ranges.begin(); - std::map Dst2SrcIdxMap; - for (Ranges::iterator I = Other.ranges.begin(), - E = Other.ranges.end(); I != E; ++I) { - // Map the ValId in the other live range to the current live range. - if (I->ValId == MergedSrcValIdx) - I->ValId = MergedDstValIdx; - else { - unsigned &NV = Dst2SrcIdxMap[I->ValId]; - if (NV == 0) NV = getNextValue(); - I->ValId = NV; + // If we have to apply a mapping to our base interval assignment, rewrite it + // now. + if (MustMapCurValNos) { + // Map the first live range. + iterator OutIt = begin(); + OutIt->valno = NewVNInfo[LHSValNoAssignments[OutIt->valno->id]]; + ++OutIt; + for (iterator I = OutIt, E = end(); I != E; ++I) { + OutIt->valno = NewVNInfo[LHSValNoAssignments[I->valno->id]]; + + // If this live range has the same value # as its immediate predecessor, + // and if they are neighbors, remove one LiveRange. This happens when we + // have [0,3:0)[4,7:1) and map 0/1 onto the same value #. + if (OutIt->valno == (OutIt-1)->valno && (OutIt-1)->end == OutIt->start) { + (OutIt-1)->end = OutIt->end; + } else { + if (I != OutIt) { + OutIt->start = I->start; + OutIt->end = I->end; + } + + // Didn't merge, on to the next one. + ++OutIt; + } } + + // If we merge some live ranges, chop off the end. + ranges.erase(OutIt, end()); + } + // Remember assignements because val# ids are changing. + SmallVector OtherAssignments; + for (iterator I = Other.begin(), E = Other.end(); I != E; ++I) + OtherAssignments.push_back(RHSValNoAssignments[I->valno->id]); + + // Update val# info. Renumber them and make sure they all belong to this + // LiveInterval now. Also remove dead val#'s. + unsigned NumValNos = 0; + for (unsigned i = 0; i < NumNewVals; ++i) { + VNInfo *VNI = NewVNInfo[i]; + if (VNI) { + if (i >= NumVals) + valnos.push_back(VNI); + else + valnos[NumValNos] = VNI; + VNI->id = NumValNos++; // Renumber val#. + } + } + if (NumNewVals < NumVals) + valnos.resize(NumNewVals); // shrinkify + + // Okay, now insert the RHS live ranges into the LHS. + iterator InsertPos = begin(); + unsigned RangeNo = 0; + for (iterator I = Other.begin(), E = Other.end(); I != E; ++I, ++RangeNo) { + // Map the valno in the other live range to the current live range. + I->valno = NewVNInfo[OtherAssignments[RangeNo]]; + assert(I->valno && "Adding a dead range?"); InsertPos = addRangeFrom(*I, InsertPos); } weight += Other.weight; + if (Other.preference && !preference) + preference = Other.preference; } -std::ostream& llvm::operator<<(std::ostream& os, const LiveRange &LR) { - return os << '[' << LR.start << ',' << LR.end << ':' << LR.ValId << ")"; +/// 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); + } } -void LiveRange::dump() const { - std::cerr << *this << "\n"; + +/// 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 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 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; + } + } + } + } } -std::ostream& llvm::operator<<(std::ostream& os, const LiveInterval& li) { - os << "%reg" << li.reg << ',' << li.weight; - if (li.empty()) - return os << "EMPTY"; +/// 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); + } +} - os << " = "; - for (LiveInterval::Ranges::const_iterator i = li.ranges.begin(), - e = li.ranges.end(); i != e; ++i) - os << *i; - return os; +/// 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. +VNInfo* 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; + } + + return V2; +} + +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; +} + +std::ostream& llvm::operator<<(std::ostream& os, const LiveRange &LR) { + return os << '[' << LR.start << ',' << LR.end << ':' << LR.valno->id << ")"; +} + +void LiveRange::dump() const { + cerr << *this << "\n"; +} + +void LiveInterval::print(std::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; + + if (empty()) + OS << " EMPTY"; + else { + OS << " = "; + for (LiveInterval::Ranges::const_iterator I = ranges.begin(), + E = ranges.end(); I != E; ++I) + OS << *I; + } + + // Print value number info. + if (getNumValNums()) { + OS << " "; + unsigned vnum = 0; + for (const_vni_iterator i = vni_begin(), e = vni_end(); i != e; + ++i, ++vnum) { + const VNInfo *vni = *i; + if (vnum) OS << " "; + OS << vnum << "@"; + if (vni->def == ~1U) { + OS << "x"; + } else { + if (vni->def == ~0U) + OS << "?"; + else + OS << vni->def; + unsigned ee = vni->kills.size(); + if (ee || vni->hasPHIKill) { + OS << "-("; + for (unsigned j = 0; j != ee; ++j) { + OS << vni->kills[j]; + if (j != ee-1) + OS << " "; + } + if (vni->hasPHIKill) { + if (ee) + OS << " "; + OS << "phi"; + } + OS << ")"; + } + } + } + } } void LiveInterval::dump() const { - std::cerr << *this << "\n"; + cerr << *this << "\n"; +} + + +void LiveRange::print(std::ostream &os) const { + os << *this; }