X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FRegisterCoalescer.cpp;h=e7b32179bde59adb8bf7e58544e87f87d6798d69;hb=54f1a90d457ca270ee9ae84f521fe016cb830ee4;hp=292e836c495a9e656f49f2cf10c49a65a6cc2504;hpb=d3c712e50b3e7f06e8027b50e922956fbd00cb70;p=oota-llvm.git diff --git a/lib/CodeGen/RegisterCoalescer.cpp b/lib/CodeGen/RegisterCoalescer.cpp index 292e836c495..e7b32179bde 100644 --- a/lib/CodeGen/RegisterCoalescer.cpp +++ b/lib/CodeGen/RegisterCoalescer.cpp @@ -32,7 +32,6 @@ #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" -#include "llvm/Support/Format.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Target/TargetInstrInfo.h" #include "llvm/Target/TargetMachine.h" @@ -93,7 +92,7 @@ namespace { /// A LaneMask to remember on which subregister live ranges we need to call /// shrinkToUses() later. - unsigned ShrinkMask; + LaneBitmask ShrinkMask; /// True if the main range of the currently coalesced intervals should be /// checked for smaller live intervals. @@ -164,15 +163,13 @@ namespace { /// LaneMask are split as necessary. @p LaneMask are the lanes that /// @p ToMerge will occupy in the coalescer register. @p LI has its subrange /// lanemasks already adjusted to the coalesced register. - /// @returns false if live range conflicts couldn't get resolved. - bool mergeSubRangeInto(LiveInterval &LI, const LiveRange &ToMerge, - unsigned LaneMask, CoalescerPair &CP); + void mergeSubRangeInto(LiveInterval &LI, const LiveRange &ToMerge, + LaneBitmask LaneMask, CoalescerPair &CP); /// Join the liveranges of two subregisters. Joins @p RRange into /// @p LRange, @p RRange may be invalid afterwards. - /// @returns false if live range conflicts couldn't get resolved. - bool joinSubRegRanges(LiveRange &LRange, LiveRange &RRange, - unsigned LaneMask, const CoalescerPair &CP); + void joinSubRegRanges(LiveRange &LRange, LiveRange &RRange, + LaneBitmask LaneMask, const CoalescerPair &CP); /// We found a non-trivially-coalescable copy. If the source value number is /// defined by a copy from the destination reg see if we can merge these two @@ -224,30 +221,17 @@ namespace { /// Dst, we can drop \p Copy. bool applyTerminalRule(const MachineInstr &Copy) const; - /// Check whether or not \p LI is composed by multiple connected - /// components and if that is the case, fix that. - void splitNewRanges(LiveInterval *LI) { - ConnectedVNInfoEqClasses ConEQ(*LIS); - unsigned NumComps = ConEQ.Classify(LI); - if (NumComps <= 1) - return; - SmallVector NewComps(1, LI); - for (unsigned i = 1; i != NumComps; ++i) { - unsigned VReg = MRI->createVirtualRegister(MRI->getRegClass(LI->reg)); - NewComps.push_back(&LIS->createEmptyInterval(VReg)); - } - - ConEQ.Distribute(&NewComps[0], *MRI); - } - /// Wrapper method for \see LiveIntervals::shrinkToUses. /// This method does the proper fixing of the live-ranges when the afore /// mentioned method returns true. void shrinkToUses(LiveInterval *LI, SmallVectorImpl *Dead = nullptr) { - if (LIS->shrinkToUses(LI, Dead)) - // We may have created multiple connected components, split them. - splitNewRanges(LI); + if (LIS->shrinkToUses(LI, Dead)) { + /// Check whether or not \p LI is composed by multiple connected + /// components and if that is the case, fix that. + SmallVector SplitLIs; + LIS->splitSeparateComponents(*LI, SplitLIs); + } } public: @@ -275,7 +259,7 @@ INITIALIZE_PASS_BEGIN(RegisterCoalescer, "simple-register-coalescing", INITIALIZE_PASS_DEPENDENCY(LiveIntervals) INITIALIZE_PASS_DEPENDENCY(SlotIndexes) INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo) -INITIALIZE_AG_DEPENDENCY(AliasAnalysis) +INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass) INITIALIZE_PASS_END(RegisterCoalescer, "simple-register-coalescing", "Simple Register Coalescing", false, false) @@ -453,7 +437,7 @@ bool CoalescerPair::isCoalescable(const MachineInstr *MI) const { void RegisterCoalescer::getAnalysisUsage(AnalysisUsage &AU) const { AU.setPreservesCFG(); - AU.addRequired(); + AU.addRequired(); AU.addRequired(); AU.addPreserved(); AU.addPreserved(); @@ -679,14 +663,18 @@ bool RegisterCoalescer::removeCopyByCommutingDef(const CoalescerPair &CP, unsigned UseOpIdx; if (!DefMI->isRegTiedToUseOperand(DefIdx, &UseOpIdx)) return false; - unsigned Op1, Op2, NewDstIdx; - if (!TII->findCommutedOpIndices(DefMI, Op1, Op2)) - return false; - if (Op1 == UseOpIdx) - NewDstIdx = Op2; - else if (Op2 == UseOpIdx) - NewDstIdx = Op1; - else + + // FIXME: The code below tries to commute 'UseOpIdx' operand with some other + // commutable operand which is expressed by 'CommuteAnyOperandIndex'value + // passed to the method. That _other_ operand is chosen by + // the findCommutedOpIndices() method. + // + // That is obviously an area for improvement in case of instructions having + // more than 2 operands. For example, if some instruction has 3 commutable + // operands then all possible variants (i.e. op#1<->op#2, op#1<->op#3, + // op#2<->op#3) of commute transformation should be considered/tried here. + unsigned NewDstIdx = TargetInstrInfo::CommuteAnyOperandIndex; + if (!TII->findCommutedOpIndices(DefMI, UseOpIdx, NewDstIdx)) return false; MachineOperand &NewDstMO = DefMI->getOperand(NewDstIdx); @@ -719,7 +707,8 @@ bool RegisterCoalescer::removeCopyByCommutingDef(const CoalescerPair &CP, // At this point we have decided that it is legal to do this // transformation. Start by commuting the instruction. MachineBasicBlock *MBB = DefMI->getParent(); - MachineInstr *NewMI = TII->commuteInstruction(DefMI); + MachineInstr *NewMI = + TII->commuteInstruction(DefMI, false, UseOpIdx, NewDstIdx); if (!NewMI) return false; if (TargetRegisterInfo::isVirtualRegister(IntA.reg) && @@ -804,7 +793,7 @@ bool RegisterCoalescer::removeCopyByCommutingDef(const CoalescerPair &CP, BumpPtrAllocator &Allocator = LIS->getVNInfoAllocator(); if (IntB.hasSubRanges()) { if (!IntA.hasSubRanges()) { - unsigned Mask = MRI->getMaxLaneMaskForVReg(IntA.reg); + LaneBitmask Mask = MRI->getMaxLaneMaskForVReg(IntA.reg); IntA.createSubRangeFrom(Allocator, Mask, IntA); } SlotIndex AIdx = CopyIdx.getRegSlot(true); @@ -812,20 +801,21 @@ bool RegisterCoalescer::removeCopyByCommutingDef(const CoalescerPair &CP, VNInfo *ASubValNo = SA.getVNInfoAt(AIdx); assert(ASubValNo != nullptr); - unsigned AMask = SA.LaneMask; + LaneBitmask AMask = SA.LaneMask; for (LiveInterval::SubRange &SB : IntB.subranges()) { - unsigned BMask = SB.LaneMask; - unsigned Common = BMask & AMask; + LaneBitmask BMask = SB.LaneMask; + LaneBitmask Common = BMask & AMask; if (Common == 0) continue; - DEBUG( - dbgs() << format("\t\tCopy+Merge %04X into %04X\n", BMask, Common)); - unsigned BRest = BMask & ~AMask; + DEBUG( dbgs() << "\t\tCopy_Merge " << PrintLaneMask(BMask) + << " into " << PrintLaneMask(Common) << '\n'); + LaneBitmask BRest = BMask & ~AMask; LiveInterval::SubRange *CommonRange; if (BRest != 0) { SB.LaneMask = BRest; - DEBUG(dbgs() << format("\t\tReduce Lane to %04X\n", BRest)); + DEBUG(dbgs() << "\t\tReduce Lane to " << PrintLaneMask(BRest) + << '\n'); // Duplicate SubRange for newly merged common stuff. CommonRange = IntB.createSubRangeFrom(Allocator, Common, SB); } else { @@ -842,7 +832,7 @@ bool RegisterCoalescer::removeCopyByCommutingDef(const CoalescerPair &CP, AMask &= ~BMask; } if (AMask != 0) { - DEBUG(dbgs() << format("\t\tNew Lane %04X\n", AMask)); + DEBUG(dbgs() << "\t\tNew Lane " << PrintLaneMask(AMask) << '\n'); LiveRange *NewRange = IntB.createSubRange(Allocator, AMask); VNInfo *BSubValNo = NewRange->getNextValue(CopyIdx, Allocator); addSegmentsWithValNo(*NewRange, BSubValNo, SA, ASubValNo); @@ -1107,7 +1097,7 @@ bool RegisterCoalescer::eliminateUndefCopy(MachineInstr *CopyMI) { const LiveInterval &SrcLI = LIS->getInterval(SrcReg); // CopyMI is undef iff SrcReg is not live before the instruction. if (SrcSubIdx != 0 && SrcLI.hasSubRanges()) { - unsigned SrcMask = TRI->getSubRegIndexLaneMask(SrcSubIdx); + LaneBitmask SrcMask = TRI->getSubRegIndexLaneMask(SrcSubIdx); for (const LiveInterval::SubRange &SR : SrcLI.subranges()) { if ((SR.LaneMask & SrcMask) == 0) continue; @@ -1128,7 +1118,7 @@ bool RegisterCoalescer::eliminateUndefCopy(MachineInstr *CopyMI) { DstLI.MergeValueNumberInto(VNI, PrevVNI); // The affected subregister segments can be removed. - unsigned DstMask = TRI->getSubRegIndexLaneMask(DstSubIdx); + LaneBitmask DstMask = TRI->getSubRegIndexLaneMask(DstSubIdx); for (LiveInterval::SubRange &SR : DstLI.subranges()) { if ((SR.LaneMask & DstMask) == 0) continue; @@ -1147,7 +1137,7 @@ bool RegisterCoalescer::eliminateUndefCopy(MachineInstr *CopyMI) { continue; const MachineInstr &MI = *MO.getParent(); SlotIndex UseIdx = LIS->getInstructionIndex(&MI); - unsigned UseMask = TRI->getSubRegIndexLaneMask(MO.getSubReg()); + LaneBitmask UseMask = TRI->getSubRegIndexLaneMask(MO.getSubReg()); bool isLive; if (UseMask != ~0u && DstLI.hasSubRanges()) { isLive = false; @@ -1213,10 +1203,10 @@ void RegisterCoalescer::updateRegDefsUses(unsigned SrcReg, if (SubIdx != 0 && MO.isUse() && MRI->shouldTrackSubRegLiveness(DstReg)) { if (!DstInt->hasSubRanges()) { BumpPtrAllocator &Allocator = LIS->getVNInfoAllocator(); - unsigned Mask = MRI->getMaxLaneMaskForVReg(DstInt->reg); + LaneBitmask Mask = MRI->getMaxLaneMaskForVReg(DstInt->reg); DstInt->createSubRangeFrom(Allocator, Mask, *DstInt); } - unsigned Mask = TRI->getSubRegIndexLaneMask(SubIdx); + LaneBitmask Mask = TRI->getSubRegIndexLaneMask(SubIdx); bool IsUndef = true; SlotIndex MIIdx = UseMI->isDebugValue() ? LIS->getSlotIndexes()->getIndexBefore(UseMI) @@ -1445,8 +1435,8 @@ bool RegisterCoalescer::joinCopy(MachineInstr *CopyMI, bool &Again) { for (LiveInterval::SubRange &S : LI.subranges()) { if ((S.LaneMask & ShrinkMask) == 0) continue; - DEBUG(dbgs() << "Shrink LaneUses (Lane " - << format("%04X", S.LaneMask) << ")\n"); + DEBUG(dbgs() << "Shrink LaneUses (Lane " << PrintLaneMask(S.LaneMask) + << ")\n"); LIS->shrinkToUses(S, LI.reg); } LI.removeEmptySubRanges(); @@ -1644,7 +1634,7 @@ class JoinVals { const unsigned SubIdx; /// The LaneMask that this liverange will occupy the coalesced register. May /// be smaller than the lanemask produced by SubIdx when merging subranges. - const unsigned LaneMask; + const LaneBitmask LaneMask; /// This is true when joining sub register ranges, false when joining main /// ranges. @@ -1699,11 +1689,11 @@ class JoinVals { ConflictResolution Resolution; /// Lanes written by this def, 0 for unanalyzed values. - unsigned WriteLanes; + LaneBitmask WriteLanes; /// Lanes with defined values in this register. Other lanes are undef and /// safe to clobber. - unsigned ValidLanes; + LaneBitmask ValidLanes; /// Value in LI being redefined by this def. VNInfo *RedefVNI; @@ -1744,7 +1734,7 @@ class JoinVals { /// Compute the bitmask of lanes actually written by DefMI. /// Set Redef if there are any partial register definitions that depend on the /// previous value of the register. - unsigned computeWriteLanes(const MachineInstr *DefMI, bool &Redef) const; + LaneBitmask computeWriteLanes(const MachineInstr *DefMI, bool &Redef) const; /// Find the ultimate value that VNI was copied from. std::pair followCopyChain(const VNInfo *VNI) const; @@ -1780,12 +1770,12 @@ class JoinVals { /// entry to TaintedVals. /// /// Returns false if the tainted lanes extend beyond the basic block. - bool taintExtent(unsigned, unsigned, JoinVals&, - SmallVectorImpl >&); + bool taintExtent(unsigned, LaneBitmask, JoinVals&, + SmallVectorImpl >&); /// Return true if MI uses any of the given Lanes from Reg. /// This does not include partial redefinitions of Reg. - bool usesLanes(const MachineInstr *MI, unsigned, unsigned, unsigned) const; + bool usesLanes(const MachineInstr *MI, unsigned, unsigned, LaneBitmask) const; /// Determine if ValNo is a copy of a value number in LR or Other.LR that will /// be pruned: @@ -1796,7 +1786,7 @@ class JoinVals { bool isPrunedValue(unsigned ValNo, JoinVals &Other); public: - JoinVals(LiveRange &LR, unsigned Reg, unsigned SubIdx, unsigned LaneMask, + JoinVals(LiveRange &LR, unsigned Reg, unsigned SubIdx, LaneBitmask LaneMask, SmallVectorImpl &newVNInfo, const CoalescerPair &cp, LiveIntervals *lis, const TargetRegisterInfo *TRI, bool SubRangeJoin, bool TrackSubRegLiveness) @@ -1823,7 +1813,7 @@ public: /// Removes subranges starting at copies that get removed. This sometimes /// happens when undefined subranges are copied around. These ranges contain /// no useful information and can be removed. - void pruneSubRegValues(LiveInterval &LI, unsigned &ShrinkMask); + void pruneSubRegValues(LiveInterval &LI, LaneBitmask &ShrinkMask); /// Erase any machine instructions that have been coalesced away. /// Add erased instructions to ErasedInstrs. @@ -1840,9 +1830,9 @@ public: }; } // end anonymous namespace -unsigned JoinVals::computeWriteLanes(const MachineInstr *DefMI, bool &Redef) +LaneBitmask JoinVals::computeWriteLanes(const MachineInstr *DefMI, bool &Redef) const { - unsigned L = 0; + LaneBitmask L = 0; for (const MachineOperand &MO : DefMI->operands()) { if (!MO.isReg() || MO.getReg() != Reg || !MO.isDef()) continue; @@ -1879,7 +1869,7 @@ std::pair JoinVals::followCopyChain( ValueIn = nullptr; for (const LiveInterval::SubRange &S : LI.subranges()) { // Transform lanemask to a mask in the joined live interval. - unsigned SMask = TRI->composeSubRegIndexLaneMask(SubIdx, S.LaneMask); + LaneBitmask SMask = TRI->composeSubRegIndexLaneMask(SubIdx, S.LaneMask); if ((SMask & LaneMask) == 0) continue; LiveQueryResult LRQ = S.Query(Def); @@ -1928,7 +1918,7 @@ JoinVals::analyzeValue(unsigned ValNo, JoinVals &Other) { const MachineInstr *DefMI = nullptr; if (VNI->isPHIDef()) { // Conservatively assume that all lanes in a PHI are valid. - unsigned Lanes = SubRangeJoin ? 1 : TRI->getSubRegIndexLaneMask(SubIdx); + LaneBitmask Lanes = SubRangeJoin ? 1 : TRI->getSubRegIndexLaneMask(SubIdx); V.ValidLanes = V.WriteLanes = Lanes; } else { DefMI = Indexes->getInstructionFromIndex(VNI->def); @@ -2190,8 +2180,8 @@ bool JoinVals::mapValues(JoinVals &Other) { } bool JoinVals:: -taintExtent(unsigned ValNo, unsigned TaintedLanes, JoinVals &Other, - SmallVectorImpl > &TaintExtent) { +taintExtent(unsigned ValNo, LaneBitmask TaintedLanes, JoinVals &Other, + SmallVectorImpl > &TaintExtent) { VNInfo *VNI = LR.getValNumInfo(ValNo); MachineBasicBlock *MBB = Indexes->getMBBFromIndex(VNI->def); SlotIndex MBBEnd = Indexes->getMBBEndIdx(MBB); @@ -2230,7 +2220,7 @@ taintExtent(unsigned ValNo, unsigned TaintedLanes, JoinVals &Other, } bool JoinVals::usesLanes(const MachineInstr *MI, unsigned Reg, unsigned SubIdx, - unsigned Lanes) const { + LaneBitmask Lanes) const { if (MI->isDebugValue()) return false; for (const MachineOperand &MO : MI->operands()) { @@ -2264,8 +2254,8 @@ bool JoinVals::resolveConflicts(JoinVals &Other) { // VNI is known to clobber some lanes in OtherVNI. If we go ahead with the // join, those lanes will be tainted with a wrong value. Get the extent of // the tainted lanes. - unsigned TaintedLanes = V.WriteLanes & OtherV.ValidLanes; - SmallVector, 8> TaintExtent; + LaneBitmask TaintedLanes = V.WriteLanes & OtherV.ValidLanes; + SmallVector, 8> TaintExtent; if (!taintExtent(i, TaintedLanes, Other, TaintExtent)) // Tainted lanes would extend beyond the basic block. return false; @@ -2384,7 +2374,7 @@ void JoinVals::pruneValues(JoinVals &Other, } } -void JoinVals::pruneSubRegValues(LiveInterval &LI, unsigned &ShrinkMask) +void JoinVals::pruneSubRegValues(LiveInterval &LI, LaneBitmask &ShrinkMask) { // Look for values being erased. bool DidPrune = false; @@ -2401,7 +2391,7 @@ void JoinVals::pruneSubRegValues(LiveInterval &LI, unsigned &ShrinkMask) // copied and we must remove that subrange value as well. VNInfo *ValueOut = Q.valueOutOrDead(); if (ValueOut != nullptr && Q.valueIn() == nullptr) { - DEBUG(dbgs() << "\t\tPrune sublane " << format("%04X", S.LaneMask) + DEBUG(dbgs() << "\t\tPrune sublane " << PrintLaneMask(S.LaneMask) << " at " << Def << "\n"); LIS->pruneValue(S, Def, nullptr); DidPrune = true; @@ -2412,8 +2402,8 @@ void JoinVals::pruneSubRegValues(LiveInterval &LI, unsigned &ShrinkMask) // If a subrange ends at the copy, then a value was copied but only // partially used later. Shrink the subregister range appropriately. if (Q.valueIn() != nullptr && Q.valueOut() == nullptr) { - DEBUG(dbgs() << "\t\tDead uses at sublane " - << format("%04X", S.LaneMask) << " at " << Def << "\n"); + DEBUG(dbgs() << "\t\tDead uses at sublane " << PrintLaneMask(S.LaneMask) + << " at " << Def << "\n"); ShrinkMask |= S.LaneMask; } } @@ -2477,8 +2467,8 @@ void JoinVals::eraseInstrs(SmallPtrSetImpl &ErasedInstrs, } } -bool RegisterCoalescer::joinSubRegRanges(LiveRange &LRange, LiveRange &RRange, - unsigned LaneMask, +void RegisterCoalescer::joinSubRegRanges(LiveRange &LRange, LiveRange &RRange, + LaneBitmask LaneMask, const CoalescerPair &CP) { SmallVector NewVNInfo; JoinVals RHSVals(RRange, CP.getSrcReg(), CP.getSrcIdx(), LaneMask, @@ -2492,13 +2482,15 @@ bool RegisterCoalescer::joinSubRegRanges(LiveRange &LRange, LiveRange &RRange, // ranges get mapped to the "overflow" lane mask bit which creates unexpected // interferences. if (!LHSVals.mapValues(RHSVals) || !RHSVals.mapValues(LHSVals)) { - DEBUG(dbgs() << "*** Couldn't join subrange!\n"); - return false; + // We already determined that it is legal to merge the intervals, so this + // should never fail. + llvm_unreachable("*** Couldn't join subrange!\n"); } if (!LHSVals.resolveConflicts(RHSVals) || !RHSVals.resolveConflicts(LHSVals)) { - DEBUG(dbgs() << "*** Couldn't join subrange!\n"); - return false; + // We already determined that it is legal to merge the intervals, so this + // should never fail. + llvm_unreachable("*** Couldn't join subrange!\n"); } // The merging algorithm in LiveInterval::join() can't handle conflicting @@ -2521,36 +2513,37 @@ bool RegisterCoalescer::joinSubRegRanges(LiveRange &LRange, LiveRange &RRange, DEBUG(dbgs() << "\t\tjoined lanes: " << LRange << "\n"); if (EndPoints.empty()) - return true; + return; // Recompute the parts of the live range we had to remove because of // CR_Replace conflicts. DEBUG(dbgs() << "\t\trestoring liveness to " << EndPoints.size() << " points: " << LRange << '\n'); LIS->extendToIndices(LRange, EndPoints); - return true; } -bool RegisterCoalescer::mergeSubRangeInto(LiveInterval &LI, +void RegisterCoalescer::mergeSubRangeInto(LiveInterval &LI, const LiveRange &ToMerge, - unsigned LaneMask, CoalescerPair &CP) { + LaneBitmask LaneMask, + CoalescerPair &CP) { BumpPtrAllocator &Allocator = LIS->getVNInfoAllocator(); for (LiveInterval::SubRange &R : LI.subranges()) { - unsigned RMask = R.LaneMask; + LaneBitmask RMask = R.LaneMask; // LaneMask of subregisters common to subrange R and ToMerge. - unsigned Common = RMask & LaneMask; + LaneBitmask Common = RMask & LaneMask; // There is nothing to do without common subregs. if (Common == 0) continue; - DEBUG(dbgs() << format("\t\tCopy+Merge %04X into %04X\n", RMask, Common)); + DEBUG(dbgs() << "\t\tCopy+Merge " << PrintLaneMask(RMask) << " into " + << PrintLaneMask(Common) << '\n'); // LaneMask of subregisters contained in the R range but not in ToMerge, // they have to split into their own subrange. - unsigned LRest = RMask & ~LaneMask; + LaneBitmask LRest = RMask & ~LaneMask; LiveInterval::SubRange *CommonRange; if (LRest != 0) { R.LaneMask = LRest; - DEBUG(dbgs() << format("\t\tReduce Lane to %04X\n", LRest)); + DEBUG(dbgs() << "\t\tReduce Lane to " << PrintLaneMask(LRest) << '\n'); // Duplicate SubRange for newly merged common stuff. CommonRange = LI.createSubRangeFrom(Allocator, Common, R); } else { @@ -2559,16 +2552,14 @@ bool RegisterCoalescer::mergeSubRangeInto(LiveInterval &LI, CommonRange = &R; } LiveRange RangeCopy(ToMerge, Allocator); - if (!joinSubRegRanges(*CommonRange, RangeCopy, Common, CP)) - return false; + joinSubRegRanges(*CommonRange, RangeCopy, Common, CP); LaneMask &= ~RMask; } if (LaneMask != 0) { - DEBUG(dbgs() << format("\t\tNew Lane %04X\n", LaneMask)); + DEBUG(dbgs() << "\t\tNew Lane " << PrintLaneMask(LaneMask) << '\n'); LI.createSubRangeFrom(Allocator, LaneMask, ToMerge); } - return true; } bool RegisterCoalescer::joinVirtRegs(CoalescerPair &CP) { @@ -2602,15 +2593,15 @@ bool RegisterCoalescer::joinVirtRegs(CoalescerPair &CP) { // create initial subranges if necessary. unsigned DstIdx = CP.getDstIdx(); if (!LHS.hasSubRanges()) { - unsigned Mask = DstIdx == 0 ? CP.getNewRC()->getLaneMask() - : TRI->getSubRegIndexLaneMask(DstIdx); + LaneBitmask Mask = DstIdx == 0 ? CP.getNewRC()->getLaneMask() + : TRI->getSubRegIndexLaneMask(DstIdx); // LHS must support subregs or we wouldn't be in this codepath. assert(Mask != 0); LHS.createSubRangeFrom(Allocator, Mask, LHS); } else if (DstIdx != 0) { // Transform LHS lanemasks to new register class if necessary. for (LiveInterval::SubRange &R : LHS.subranges()) { - unsigned Mask = TRI->composeSubRegIndexLaneMask(DstIdx, R.LaneMask); + LaneBitmask Mask = TRI->composeSubRegIndexLaneMask(DstIdx, R.LaneMask); R.LaneMask = Mask; } } @@ -2619,41 +2610,21 @@ bool RegisterCoalescer::joinVirtRegs(CoalescerPair &CP) { // Determine lanemasks of RHS in the coalesced register and merge subranges. unsigned SrcIdx = CP.getSrcIdx(); - bool Abort = false; if (!RHS.hasSubRanges()) { - unsigned Mask = SrcIdx == 0 ? CP.getNewRC()->getLaneMask() - : TRI->getSubRegIndexLaneMask(SrcIdx); - if (!mergeSubRangeInto(LHS, RHS, Mask, CP)) - Abort = true; + LaneBitmask Mask = SrcIdx == 0 ? CP.getNewRC()->getLaneMask() + : TRI->getSubRegIndexLaneMask(SrcIdx); + mergeSubRangeInto(LHS, RHS, Mask, CP); } else { // Pair up subranges and merge. for (LiveInterval::SubRange &R : RHS.subranges()) { - unsigned Mask = TRI->composeSubRegIndexLaneMask(SrcIdx, R.LaneMask); - if (!mergeSubRangeInto(LHS, R, Mask, CP)) { - Abort = true; - break; - } + LaneBitmask Mask = TRI->composeSubRegIndexLaneMask(SrcIdx, R.LaneMask); + mergeSubRangeInto(LHS, R, Mask, CP); } } - if (Abort) { - // This shouldn't have happened :-( - // However we are aware of at least one existing problem where we - // can't merge subranges when multiple ranges end up in the - // "overflow bit" 32. As a workaround we drop all subregister ranges - // which means we loose some precision but are back to a well defined - // state. - assert(TargetRegisterInfo::isImpreciseLaneMask( - CP.getNewRC()->getLaneMask()) - && "SubRange merge should only fail when merging into bit 32."); - DEBUG(dbgs() << "\tSubrange join aborted!\n"); - LHS.clearSubRanges(); - RHS.clearSubRanges(); - } else { - DEBUG(dbgs() << "\tJoined SubRanges " << LHS << "\n"); + DEBUG(dbgs() << "\tJoined SubRanges " << LHS << "\n"); - LHSVals.pruneSubRegValues(LHS, ShrinkMask); - RHSVals.pruneSubRegValues(LHS, ShrinkMask); - } + LHSVals.pruneSubRegValues(LHS, ShrinkMask); + RHSVals.pruneSubRegValues(LHS, ShrinkMask); } // The merging algorithm in LiveInterval::join() can't handle conflicting @@ -2904,7 +2875,7 @@ void RegisterCoalescer::joinAllIntervals() { std::vector MBBs; MBBs.reserve(MF->size()); for (MachineFunction::iterator I = MF->begin(), E = MF->end();I != E;++I){ - MachineBasicBlock *MBB = I; + MachineBasicBlock *MBB = &*I; MBBs.push_back(MBBPriorityInfo(MBB, Loops->getLoopDepth(MBB), JoinSplitEdges && isSplitEdge(MBB))); } @@ -2943,7 +2914,7 @@ bool RegisterCoalescer::runOnMachineFunction(MachineFunction &fn) { TRI = STI.getRegisterInfo(); TII = STI.getInstrInfo(); LIS = &getAnalysis(); - AA = &getAnalysis(); + AA = &getAnalysis().getAAResults(); Loops = &getAnalysis(); if (EnableGlobalCopies == cl::BOU_UNSET) JoinGlobalCopies = STI.enableJoinGlobalCopies(); @@ -2981,22 +2952,25 @@ bool RegisterCoalescer::runOnMachineFunction(MachineFunction &fn) { if (MRI->recomputeRegClass(Reg)) { DEBUG(dbgs() << PrintReg(Reg) << " inflated to " << TRI->getRegClassName(MRI->getRegClass(Reg)) << '\n'); + ++NumInflated; + LiveInterval &LI = LIS->getInterval(Reg); - unsigned MaxMask = MRI->getMaxLaneMaskForVReg(Reg); - if (MaxMask == 0) { + if (LI.hasSubRanges()) { // If the inflated register class does not support subregisters anymore // remove the subranges. - LI.clearSubRanges(); - } else { + if (!MRI->shouldTrackSubRegLiveness(Reg)) { + LI.clearSubRanges(); + } else { #ifndef NDEBUG - // If subranges are still supported, then the same subregs should still - // be supported. - for (LiveInterval::SubRange &S : LI.subranges()) { - assert ((S.LaneMask & ~MaxMask) == 0); - } + LaneBitmask MaxMask = MRI->getMaxLaneMaskForVReg(Reg); + // If subranges are still supported, then the same subregs + // should still be supported. + for (LiveInterval::SubRange &S : LI.subranges()) { + assert((S.LaneMask & ~MaxMask) == 0); + } #endif + } } - ++NumInflated; } }