Reapply 91184 with fixes and an addition to the testcase to cover the problem
[oota-llvm.git] / lib / CodeGen / PreAllocSplitting.cpp
index 9571b7a5eaf047aee2bc46f37ca60befce581afc..b0d7a4757eff27ddd81b44b9ba85b440d78ac8e2 100644 (file)
@@ -16,6 +16,7 @@
 
 #define DEBUG_TYPE "pre-alloc-split"
 #include "VirtRegMap.h"
+#include "llvm/CodeGen/CalcSpillWeights.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
 #include "llvm/CodeGen/LiveStackAnalysis.h"
 #include "llvm/CodeGen/MachineDominators.h"
 using namespace llvm;
 
 static cl::opt<int> PreSplitLimit("pre-split-limit", cl::init(-1), cl::Hidden);
-static cl::opt<int> DeadSplitLimit("dead-split-limit", cl::init(-1), cl::Hidden);
-static cl::opt<int> RestoreFoldLimit("restore-fold-limit", cl::init(-1), cl::Hidden);
+static cl::opt<int> DeadSplitLimit("dead-split-limit", cl::init(-1),
+                                   cl::Hidden);
+static cl::opt<int> RestoreFoldLimit("restore-fold-limit", cl::init(-1),
+                                     cl::Hidden);
 
 STATISTIC(NumSplits, "Number of intervals split");
 STATISTIC(NumRemats, "Number of intervals split by rematerialization");
@@ -50,13 +53,14 @@ STATISTIC(NumRenumbers, "Number of intervals renumbered into new registers");
 STATISTIC(NumDeadSpills, "Number of dead spills removed");
 
 namespace {
-  class VISIBILITY_HIDDEN PreAllocSplitting : public MachineFunctionPass {
+  class PreAllocSplitting : public MachineFunctionPass {
     MachineFunction       *CurrMF;
     const TargetMachine   *TM;
     const TargetInstrInfo *TII;
     const TargetRegisterInfo* TRI;
     MachineFrameInfo      *MFI;
     MachineRegisterInfo   *MRI;
+    SlotIndexes           *SIs;
     LiveIntervals         *LIs;
     LiveStacks            *LSs;
     VirtRegMap            *VRM;
@@ -68,7 +72,7 @@ namespace {
     MachineBasicBlock     *BarrierMBB;
 
     // Barrier - Current barrier index.
-    LiveIndex     BarrierIdx;
+    SlotIndex     BarrierIdx;
 
     // CurrLI - Current live interval being split.
     LiveInterval          *CurrLI;
@@ -83,23 +87,25 @@ namespace {
     DenseMap<unsigned, int> IntervalSSMap;
 
     // Def2SpillMap - A map from a def instruction index to spill index.
-    DenseMap<LiveIndex, LiveIndex> Def2SpillMap;
+    DenseMap<SlotIndex, SlotIndex> Def2SpillMap;
 
   public:
     static char ID;
-    PreAllocSplitting() : MachineFunctionPass(&ID) {}
+    PreAllocSplitting()
+      : MachineFunctionPass(&ID) {}
 
     virtual bool runOnMachineFunction(MachineFunction &MF);
 
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.setPreservesCFG();
-      AU.addRequired<LiveIndexes>();
-      AU.addPreserved<LiveIndexes>();
+      AU.addRequired<SlotIndexes>();
+      AU.addPreserved<SlotIndexes>();
       AU.addRequired<LiveIntervals>();
       AU.addPreserved<LiveIntervals>();
       AU.addRequired<LiveStacks>();
       AU.addPreserved<LiveStacks>();
       AU.addPreserved<RegisterCoalescer>();
+      AU.addPreserved<CalculateSpillWeights>();
       if (StrongPHIElim)
         AU.addPreservedID(StrongPHIEliminationID);
       else
@@ -129,25 +135,22 @@ namespace {
 
 
   private:
-    MachineBasicBlock::iterator
-      findNextEmptySlot(MachineBasicBlock*, MachineInstr*,
-                        LiveIndex&);
 
     MachineBasicBlock::iterator
       findSpillPoint(MachineBasicBlock*, MachineInstr*, MachineInstr*,
-                     SmallPtrSet<MachineInstr*, 4>&, LiveIndex&);
+                     SmallPtrSet<MachineInstr*, 4>&);
 
     MachineBasicBlock::iterator
-      findRestorePoint(MachineBasicBlock*, MachineInstr*, LiveIndex,
-                     SmallPtrSet<MachineInstr*, 4>&, LiveIndex&);
+      findRestorePoint(MachineBasicBlock*, MachineInstr*, SlotIndex,
+                     SmallPtrSet<MachineInstr*, 4>&);
 
     int CreateSpillStackSlot(unsigned, const TargetRegisterClass *);
 
     bool IsAvailableInStack(MachineBasicBlock*, unsigned,
-                            LiveIndex, LiveIndex,
-                            LiveIndex&, int&) const;
+                            SlotIndex, SlotIndex,
+                            SlotIndex&, int&) const;
 
-    void UpdateSpillSlotInterval(VNInfo*, LiveIndex, LiveIndex);
+    void UpdateSpillSlotInterval(VNInfo*, SlotIndex, SlotIndex);
 
     bool SplitRegLiveInterval(LiveInterval*);
 
@@ -159,7 +162,6 @@ namespace {
     bool Rematerialize(unsigned vreg, VNInfo* ValNo,
                        MachineInstr* DefMI,
                        MachineBasicBlock::iterator RestorePt,
-                       LiveIndex RestoreIdx,
                        SmallPtrSet<MachineInstr*, 4>& RefsInMBB);
     MachineInstr* FoldSpill(unsigned vreg, const TargetRegisterClass* RC,
                             MachineInstr* DefMI,
@@ -206,24 +208,6 @@ X("pre-alloc-splitting", "Pre-Register Allocation Live Interval Splitting");
 
 const PassInfo *const llvm::PreAllocSplittingID = &X;
 
-
-/// findNextEmptySlot - Find a gap after the given machine instruction in the
-/// instruction index map. If there isn't one, return end().
-MachineBasicBlock::iterator
-PreAllocSplitting::findNextEmptySlot(MachineBasicBlock *MBB, MachineInstr *MI,
-                                     LiveIndex &SpotIndex) {
-  MachineBasicBlock::iterator MII = MI;
-  if (++MII != MBB->end()) {
-    LiveIndex Index =
-      LIs->findGapBeforeInstr(LIs->getInstructionIndex(MII));
-    if (Index != LiveIndex()) {
-      SpotIndex = Index;
-      return MII;
-    }
-  }
-  return MBB->end();
-}
-
 /// findSpillPoint - Find a gap as far away from the given MI that's suitable
 /// for spilling the current live interval. The index must be before any
 /// defs and uses of the live interval register in the mbb. Return begin() if
@@ -231,8 +215,7 @@ PreAllocSplitting::findNextEmptySlot(MachineBasicBlock *MBB, MachineInstr *MI,
 MachineBasicBlock::iterator
 PreAllocSplitting::findSpillPoint(MachineBasicBlock *MBB, MachineInstr *MI,
                                   MachineInstr *DefMI,
-                                  SmallPtrSet<MachineInstr*, 4> &RefsInMBB,
-                                  LiveIndex &SpillIndex) {
+                                  SmallPtrSet<MachineInstr*, 4> &RefsInMBB) {
   MachineBasicBlock::iterator Pt = MBB->begin();
 
   MachineBasicBlock::iterator MII = MI;
@@ -245,8 +228,6 @@ PreAllocSplitting::findSpillPoint(MachineBasicBlock *MBB, MachineInstr *MI,
   if (MII == EndPt || RefsInMBB.count(MII)) return Pt;
     
   while (MII != EndPt && !RefsInMBB.count(MII)) {
-    LiveIndex Index = LIs->getInstructionIndex(MII);
-    
     // We can't insert the spill between the barrier (a call), and its
     // corresponding call frame setup.
     if (MII->getOpcode() == TRI->getCallFrameDestroyOpcode()) {
@@ -257,9 +238,8 @@ PreAllocSplitting::findSpillPoint(MachineBasicBlock *MBB, MachineInstr *MI,
         }
       }
       continue;
-    } else if (LIs->hasGapBeforeInstr(Index)) {
+    } else {
       Pt = MII;
-      SpillIndex = LIs->findGapBeforeInstr(Index, true);
     }
     
     if (RefsInMBB.count(MII))
@@ -278,9 +258,8 @@ PreAllocSplitting::findSpillPoint(MachineBasicBlock *MBB, MachineInstr *MI,
 /// found.
 MachineBasicBlock::iterator
 PreAllocSplitting::findRestorePoint(MachineBasicBlock *MBB, MachineInstr *MI,
-                                    LiveIndex LastIdx,
-                                    SmallPtrSet<MachineInstr*, 4> &RefsInMBB,
-                                    LiveIndex &RestoreIndex) {
+                                    SlotIndex LastIdx,
+                                    SmallPtrSet<MachineInstr*, 4> &RefsInMBB) {
   // FIXME: Allow spill to be inserted to the beginning of the mbb. Update mbb
   // begin index accordingly.
   MachineBasicBlock::iterator Pt = MBB->end();
@@ -301,10 +280,9 @@ PreAllocSplitting::findRestorePoint(MachineBasicBlock *MBB, MachineInstr *MI,
   // FIXME: Limit the number of instructions to examine to reduce
   // compile time?
   while (MII != EndPt) {
-    LiveIndex Index = LIs->getInstructionIndex(MII);
+    SlotIndex Index = LIs->getInstructionIndex(MII);
     if (Index > LastIdx)
       break;
-    LiveIndex Gap = LIs->findGapBeforeInstr(Index);
       
     // We can't insert a restore between the barrier (a call) and its 
     // corresponding call frame teardown.
@@ -313,9 +291,8 @@ PreAllocSplitting::findRestorePoint(MachineBasicBlock *MBB, MachineInstr *MI,
         if (MII == EndPt || RefsInMBB.count(MII)) return Pt;
         ++MII;
       } while (MII->getOpcode() != TRI->getCallFrameDestroyOpcode());
-    } else if (Gap != LiveIndex()) {
+    } else {
       Pt = MII;
-      RestoreIndex = Gap;
     }
     
     if (RefsInMBB.count(MII))
@@ -337,7 +314,7 @@ int PreAllocSplitting::CreateSpillStackSlot(unsigned Reg,
   if (I != IntervalSSMap.end()) {
     SS = I->second;
   } else {
-    SS = MFI->CreateStackObject(RC->getSize(), RC->getAlignment());
+    SS = MFI->CreateSpillStackObject(RC->getSize(), RC->getAlignment());
     IntervalSSMap[Reg] = SS;
   }
 
@@ -346,7 +323,7 @@ int PreAllocSplitting::CreateSpillStackSlot(unsigned Reg,
   if (CurrSLI->hasAtLeastOneValue())
     CurrSValNo = CurrSLI->getValNumInfo(0);
   else
-    CurrSValNo = CurrSLI->getNextValue(LiveIndex(), 0, false,
+    CurrSValNo = CurrSLI->getNextValue(SlotIndex(), 0, false,
                                        LSs->getVNInfoAllocator());
   return SS;
 }
@@ -355,17 +332,17 @@ int PreAllocSplitting::CreateSpillStackSlot(unsigned Reg,
 /// slot at the specified index.
 bool
 PreAllocSplitting::IsAvailableInStack(MachineBasicBlock *DefMBB,
-                                    unsigned Reg, LiveIndex DefIndex,
-                                    LiveIndex RestoreIndex,
-                                    LiveIndex &SpillIndex,
+                                    unsigned Reg, SlotIndex DefIndex,
+                                    SlotIndex RestoreIndex,
+                                    SlotIndex &SpillIndex,
                                     int& SS) const {
   if (!DefMBB)
     return false;
 
-  DenseMap<unsigned, int>::iterator I = IntervalSSMap.find(Reg);
+  DenseMap<unsigned, int>::const_iterator I = IntervalSSMap.find(Reg);
   if (I == IntervalSSMap.end())
     return false;
-  DenseMap<LiveIndex, LiveIndex>::iterator
+  DenseMap<SlotIndex, SlotIndex>::const_iterator
     II = Def2SpillMap.find(DefIndex);
   if (II == Def2SpillMap.end())
     return false;
@@ -386,8 +363,8 @@ PreAllocSplitting::IsAvailableInStack(MachineBasicBlock *DefMBB,
 /// interval being split, and the spill and restore indicies, update the live
 /// interval of the spill stack slot.
 void
-PreAllocSplitting::UpdateSpillSlotInterval(VNInfo *ValNo, LiveIndex SpillIndex,
-                                           LiveIndex RestoreIndex) {
+PreAllocSplitting::UpdateSpillSlotInterval(VNInfo *ValNo, SlotIndex SpillIndex,
+                                           SlotIndex RestoreIndex) {
   assert(LIs->getMBBFromIndex(RestoreIndex) == BarrierMBB &&
          "Expect restore in the barrier mbb");
 
@@ -400,7 +377,7 @@ PreAllocSplitting::UpdateSpillSlotInterval(VNInfo *ValNo, LiveIndex SpillIndex,
   }
 
   SmallPtrSet<MachineBasicBlock*, 4> Processed;
-  LiveIndex EndIdx = LIs->getMBBEndIdx(MBB);
+  SlotIndex EndIdx = LIs->getMBBEndIdx(MBB);
   LiveRange SLR(SpillIndex, EndIdx.getNextSlot(), CurrSValNo);
   CurrSLI->addRange(SLR);
   Processed.insert(MBB);
@@ -420,7 +397,7 @@ PreAllocSplitting::UpdateSpillSlotInterval(VNInfo *ValNo, LiveIndex SpillIndex,
     WorkList.pop_back();
     if (Processed.count(MBB))
       continue;
-    LiveIndex Idx = LIs->getMBBStartIdx(MBB);
+    SlotIndex Idx = LIs->getMBBStartIdx(MBB);
     LR = CurrLI->getLiveRangeContaining(Idx);
     if (LR && LR->valno == ValNo) {
       EndIdx = LIs->getMBBEndIdx(MBB);
@@ -493,9 +470,9 @@ PreAllocSplitting::PerformPHIConstruction(MachineBasicBlock::iterator UseI,
     }
     
     // Once we've found it, extend its VNInfo to our instruction.
-    LiveIndex DefIndex = LIs->getInstructionIndex(Walker);
+    SlotIndex DefIndex = LIs->getInstructionIndex(Walker);
     DefIndex = DefIndex.getDefIndex();
-    LiveIndex EndIndex = LIs->getMBBEndIdx(MBB);
+    SlotIndex EndIndex = LIs->getMBBEndIdx(MBB);
     
     RetVNI = NewVNs[Walker];
     LI->addRange(LiveRange(DefIndex, EndIndex.getNextSlot(), RetVNI));
@@ -530,9 +507,9 @@ PreAllocSplitting::PerformPHIConstruction(MachineBasicBlock::iterator UseI,
                                               IsTopLevel, IsIntraBlock);
     }
 
-    LiveIndex UseIndex = LIs->getInstructionIndex(Walker);
+    SlotIndex UseIndex = LIs->getInstructionIndex(Walker);
     UseIndex = UseIndex.getUseIndex();
-    LiveIndex EndIndex;
+    SlotIndex EndIndex;
     if (IsIntraBlock) {
       EndIndex = LIs->getInstructionIndex(UseI);
       EndIndex = EndIndex.getUseIndex();
@@ -590,9 +567,9 @@ PreAllocSplitting::PerformPHIConstruction(MachineBasicBlock::iterator UseI,
                                               IsTopLevel, IsIntraBlock);
     }
 
-    LiveIndex StartIndex = LIs->getInstructionIndex(Walker);
+    SlotIndex StartIndex = LIs->getInstructionIndex(Walker);
     StartIndex = foundDef ? StartIndex.getDefIndex() : StartIndex.getUseIndex();
-    LiveIndex EndIndex;
+    SlotIndex EndIndex;
     if (IsIntraBlock) {
       EndIndex = LIs->getInstructionIndex(UseI);
       EndIndex = EndIndex.getUseIndex();
@@ -641,9 +618,9 @@ PreAllocSplitting::PerformPHIConstructionFallBack(MachineBasicBlock::iterator Us
   // assume that we are not intrablock here.
   if (Phis.count(MBB)) return Phis[MBB]; 
 
-  LiveIndex StartIndex = LIs->getMBBStartIdx(MBB);
+  SlotIndex StartIndex = LIs->getMBBStartIdx(MBB);
   VNInfo *RetVNI = Phis[MBB] =
-    LI->getNextValue(LiveIndex(), /*FIXME*/ 0, false,
+    LI->getNextValue(SlotIndex(), /*FIXME*/ 0, false,
                      LIs->getVNInfoAllocator());
 
   if (!IsIntraBlock) LiveOut[MBB] = RetVNI;
@@ -686,13 +663,13 @@ PreAllocSplitting::PerformPHIConstructionFallBack(MachineBasicBlock::iterator Us
     for (DenseMap<MachineBasicBlock*, VNInfo*>::iterator I =
            IncomingVNs.begin(), E = IncomingVNs.end(); I != E; ++I) {
       I->second->setHasPHIKill(true);
-      LiveIndex KillIndex = LIs->getMBBEndIdx(I->first);
+      SlotIndex KillIndex = LIs->getMBBEndIdx(I->first);
       if (!I->second->isKill(KillIndex))
         I->second->addKill(KillIndex);
     }
   }
       
-  LiveIndex EndIndex;
+  SlotIndex EndIndex;
   if (IsIntraBlock) {
     EndIndex = LIs->getInstructionIndex(UseI);
     EndIndex = EndIndex.getUseIndex();
@@ -734,11 +711,11 @@ void PreAllocSplitting::ReconstructLiveInterval(LiveInterval* LI) {
        DE = MRI->def_end(); DI != DE; ++DI) {
     Defs[(*DI).getParent()].insert(&*DI);
     
-    LiveIndex DefIdx = LIs->getInstructionIndex(&*DI);
+    SlotIndex DefIdx = LIs->getInstructionIndex(&*DI);
     DefIdx = DefIdx.getDefIndex();
     
     assert(DI->getOpcode() != TargetInstrInfo::PHI &&
-           "Following NewVN isPHIDef flag incorrect. Fix me!");
+           "PHI instr in code during pre-alloc splitting.");
     VNInfo* NewVN = LI->getNextValue(DefIdx, 0, true, Alloc);
     
     // If the def is a move, set the copy field.
@@ -770,7 +747,7 @@ void PreAllocSplitting::ReconstructLiveInterval(LiveInterval* LI) {
   // Add ranges for dead defs
   for (MachineRegisterInfo::def_iterator DI = MRI->def_begin(LI->reg),
        DE = MRI->def_end(); DI != DE; ++DI) {
-    LiveIndex DefIdx = LIs->getInstructionIndex(&*DI);
+    SlotIndex DefIdx = LIs->getInstructionIndex(&*DI);
     DefIdx = DefIdx.getDefIndex();
     
     if (LI->liveAt(DefIdx)) continue;
@@ -785,7 +762,7 @@ void PreAllocSplitting::ReconstructLiveInterval(LiveInterval* LI) {
        VI != VE; ++VI) {
     VNInfo* VNI = *VI;
     for (unsigned i = 0, e = VNI->kills.size(); i != e; ++i) {
-      LiveIndex KillIdx = VNI->kills[i];
+      SlotIndex KillIdx = VNI->kills[i];
       if (KillIdx.isPHI())
         continue;
       MachineInstr *KillMI = LIs->getInstructionFromIndex(KillIdx);
@@ -866,7 +843,7 @@ void PreAllocSplitting::RenumberValno(VNInfo* VN) {
   for (MachineRegisterInfo::reg_iterator I = MRI->reg_begin(CurrLI->reg),
          E = MRI->reg_end(); I != E; ++I) {
     MachineOperand& MO = I.getOperand();
-    LiveIndex InstrIdx = LIs->getInstructionIndex(&*I);
+    SlotIndex InstrIdx = LIs->getInstructionIndex(&*I);
     
     if ((MO.isUse() && NewLI.liveAt(InstrIdx.getUseIndex())) ||
         (MO.isDef() && NewLI.liveAt(InstrIdx.getDefIndex())))
@@ -894,25 +871,22 @@ void PreAllocSplitting::RenumberValno(VNInfo* VN) {
 bool PreAllocSplitting::Rematerialize(unsigned VReg, VNInfo* ValNo,
                                       MachineInstr* DefMI,
                                       MachineBasicBlock::iterator RestorePt,
-                                      LiveIndex RestoreIdx,
                                     SmallPtrSet<MachineInstr*, 4>& RefsInMBB) {
   MachineBasicBlock& MBB = *RestorePt->getParent();
   
   MachineBasicBlock::iterator KillPt = BarrierMBB->end();
-  LiveIndex KillIdx;
   if (!ValNo->isDefAccurate() || DefMI->getParent() == BarrierMBB)
-    KillPt = findSpillPoint(BarrierMBB, Barrier, NULL, RefsInMBB, KillIdx);
+    KillPt = findSpillPoint(BarrierMBB, Barrier, NULL, RefsInMBB);
   else
-    KillPt = findNextEmptySlot(DefMI->getParent(), DefMI, KillIdx);
+    KillPt = llvm::next(MachineBasicBlock::iterator(DefMI));
   
   if (KillPt == DefMI->getParent()->end())
     return false;
   
-  TII->reMaterialize(MBB, RestorePt, VReg, 0, DefMI);
-  LIs->InsertMachineInstrInMaps(prior(RestorePt), RestoreIdx);
+  TII->reMaterialize(MBB, RestorePt, VReg, 0, DefMI, TRI);
+  SlotIndex RematIdx = LIs->InsertMachineInstrInMaps(prior(RestorePt));
   
   ReconstructLiveInterval(CurrLI);
-  LiveIndex RematIdx = LIs->getInstructionIndex(prior(RestorePt));
   RematIdx = RematIdx.getDefIndex();
   RenumberValno(CurrLI->findDefinedVNInfoForRegInt(RematIdx));
   
@@ -953,7 +927,7 @@ MachineInstr* PreAllocSplitting::FoldSpill(unsigned vreg,
   if (I != IntervalSSMap.end()) {
     SS = I->second;
   } else {
-    SS = MFI->CreateStackObject(RC->getSize(), RC->getAlignment());
+    SS = MFI->CreateSpillStackObject(RC->getSize(), RC->getAlignment());
   }
   
   MachineInstr* FMI = TII->foldMemoryOperand(*MBB->getParent(),
@@ -969,7 +943,7 @@ MachineInstr* PreAllocSplitting::FoldSpill(unsigned vreg,
     if (CurrSLI->hasAtLeastOneValue())
       CurrSValNo = CurrSLI->getValNumInfo(0);
     else
-      CurrSValNo = CurrSLI->getNextValue(LiveIndex(), 0, false,
+      CurrSValNo = CurrSLI->getNextValue(SlotIndex(), 0, false,
                                          LSs->getVNInfoAllocator());
   }
   
@@ -1084,17 +1058,15 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
   }
 
   // Find a point to restore the value after the barrier.
-  LiveIndex RestoreIndex;
   MachineBasicBlock::iterator RestorePt =
-    findRestorePoint(BarrierMBB, Barrier, LR->end, RefsInMBB, RestoreIndex);
+    findRestorePoint(BarrierMBB, Barrier, LR->end, RefsInMBB);
   if (RestorePt == BarrierMBB->end()) {
     DEBUG(errs() << "FAILED (could not find a suitable restore point).\n");
     return false;
   }
 
   if (DefMI && LIs->isReMaterializable(*LI, ValNo, DefMI))
-    if (Rematerialize(LI->reg, ValNo, DefMI, RestorePt,
-                      RestoreIndex, RefsInMBB)) {
+    if (Rematerialize(LI->reg, ValNo, DefMI, RestorePt, RefsInMBB)) {
       DEBUG(errs() << "success (remat).\n");
       return true;
     }
@@ -1102,7 +1074,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
   // Add a spill either before the barrier or after the definition.
   MachineBasicBlock *DefMBB = DefMI ? DefMI->getParent() : NULL;
   const TargetRegisterClass *RC = MRI->getRegClass(CurrLI->reg);
-  LiveIndex SpillIndex;
+  SlotIndex SpillIndex;
   MachineInstr *SpillMI = NULL;
   int SS = -1;
   if (!ValNo->isDefAccurate()) {
@@ -1112,7 +1084,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
       SpillIndex = LIs->getInstructionIndex(SpillMI);
     } else {
       MachineBasicBlock::iterator SpillPt = 
-        findSpillPoint(BarrierMBB, Barrier, NULL, RefsInMBB, SpillIndex);
+        findSpillPoint(BarrierMBB, Barrier, NULL, RefsInMBB);
       if (SpillPt == BarrierMBB->begin()) {
         DEBUG(errs() << "FAILED (could not find a suitable spill point).\n");
         return false; // No gap to insert spill.
@@ -1122,10 +1094,10 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
       SS = CreateSpillStackSlot(CurrLI->reg, RC);
       TII->storeRegToStackSlot(*BarrierMBB, SpillPt, CurrLI->reg, true, SS, RC);
       SpillMI = prior(SpillPt);
-      LIs->InsertMachineInstrInMaps(SpillMI, SpillIndex);
+      SpillIndex = LIs->InsertMachineInstrInMaps(SpillMI);
     }
   } else if (!IsAvailableInStack(DefMBB, CurrLI->reg, ValNo->def,
-                                 RestoreIndex, SpillIndex, SS)) {
+                                 LIs->getZeroIndex(), SpillIndex, SS)) {
     // If it's already split, just restore the value. There is no need to spill
     // the def again.
     if (!DefMI) {
@@ -1142,13 +1114,13 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
       if (DefMBB == BarrierMBB) {
         // Add spill after the def and the last use before the barrier.
         SpillPt = findSpillPoint(BarrierMBB, Barrier, DefMI,
-                                 RefsInMBB, SpillIndex);
+                                 RefsInMBB);
         if (SpillPt == DefMBB->begin()) {
           DEBUG(errs() << "FAILED (could not find a suitable spill point).\n");
           return false; // No gap to insert spill.
         }
       } else {
-        SpillPt = findNextEmptySlot(DefMBB, DefMI, SpillIndex);
+        SpillPt = llvm::next(MachineBasicBlock::iterator(DefMI));
         if (SpillPt == DefMBB->end()) {
           DEBUG(errs() << "FAILED (could not find a suitable spill point).\n");
           return false; // No gap to insert spill.
@@ -1158,7 +1130,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
       SS = CreateSpillStackSlot(CurrLI->reg, RC);
       TII->storeRegToStackSlot(*DefMBB, SpillPt, CurrLI->reg, false, SS, RC);
       SpillMI = prior(SpillPt);
-      LIs->InsertMachineInstrInMaps(SpillMI, SpillIndex);
+      SpillIndex = LIs->InsertMachineInstrInMaps(SpillMI);
     }
   }
 
@@ -1168,6 +1140,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
 
   // Add restore.
   bool FoldedRestore = false;
+  SlotIndex RestoreIndex;
   if (MachineInstr* LMI = FoldRestore(CurrLI->reg, RC, Barrier,
                                       BarrierMBB, SS, RefsInMBB)) {
     RestorePt = LMI;
@@ -1176,7 +1149,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
   } else {
     TII->loadRegFromStackSlot(*BarrierMBB, RestorePt, CurrLI->reg, SS, RC);
     MachineInstr *LoadMI = prior(RestorePt);
-    LIs->InsertMachineInstrInMaps(LoadMI, RestoreIndex);
+    RestoreIndex = LIs->InsertMachineInstrInMaps(LoadMI);
   }
 
   // Update spill stack slot live interval.
@@ -1186,7 +1159,7 @@ bool PreAllocSplitting::SplitRegLiveInterval(LiveInterval *LI) {
   ReconstructLiveInterval(CurrLI);
 
   if (!FoldedRestore) {
-    LiveIndex RestoreIdx = LIs->getInstructionIndex(prior(RestorePt));
+    SlotIndex RestoreIdx = LIs->getInstructionIndex(prior(RestorePt));
     RestoreIdx = RestoreIdx.getDefIndex();
     RenumberValno(CurrLI->findDefinedVNInfoForRegInt(RestoreIdx));
   }
@@ -1273,7 +1246,7 @@ bool PreAllocSplitting::removeDeadSpills(SmallPtrSet<LiveInterval*, 8>& split) {
     // reaching definition (VNInfo).
     for (MachineRegisterInfo::use_iterator UI = MRI->use_begin((*LI)->reg),
          UE = MRI->use_end(); UI != UE; ++UI) {
-      LiveIndex index = LIs->getInstructionIndex(&*UI);
+      SlotIndex index = LIs->getInstructionIndex(&*UI);
       index = index.getUseIndex();
       
       const LiveRange* LR = (*LI)->getLiveRangeContaining(index);
@@ -1396,7 +1369,7 @@ bool PreAllocSplitting::removeDeadSpills(SmallPtrSet<LiveInterval*, 8>& split) {
       // Otherwise, this is a load-store case, so DCE them.
       for (SmallPtrSet<MachineInstr*, 4>::iterator UI = 
            VNUseCount[CurrVN].begin(), UE = VNUseCount[CurrVN].end();
-           UI != UI; ++UI) {
+           UI != UE; ++UI) {
         LIs->RemoveMachineInstrFromMaps(*UI);
         (*UI)->eraseFromParent();
       }
@@ -1423,7 +1396,7 @@ bool PreAllocSplitting::createsNewJoin(LiveRange* LR,
   if (LR->valno->hasPHIKill())
     return false;
   
-  LiveIndex MBBEnd = LIs->getMBBEndIdx(BarrierMBB);
+  SlotIndex MBBEnd = LIs->getMBBEndIdx(BarrierMBB);
   if (LR->end < MBBEnd)
     return false;
   
@@ -1486,6 +1459,7 @@ bool PreAllocSplitting::runOnMachineFunction(MachineFunction &MF) {
   TII    = TM->getInstrInfo();
   MFI    = MF.getFrameInfo();
   MRI    = &MF.getRegInfo();
+  SIs    = &getAnalysis<SlotIndexes>();
   LIs    = &getAnalysis<LiveIntervals>();
   LSs    = &getAnalysis<LiveStacks>();
   VRM    = &getAnalysis<VirtRegMap>();