Don't track kills in VNInfo. Use interval ends instead.

The VNInfo.kills vector was almost unused except for all the code keeping it
updated. The few places using it were easily rewritten to check for interval
ends instead.

The two new methods LiveInterval::killedAt and killedInRange are replacements.

This brings us down to 3 independent data structures tracking kills.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106905 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 45 deletions

diff --git a/lib/CodeGen/PreAllocSplitting.cpp b/lib/CodeGen/PreAllocSplitting.cpp
index c1db4e2fbc..8784dc965c 100644
--- a/lib/CodeGen/PreAllocSplitting.cpp
+++ b/lib/CodeGen/PreAllocSplitting.cpp
@@ -512,9 +512,6 @@ PreAllocSplitting::PerformPHIConstruction(MachineBasicBlock::iterator UseI,
     LI->addRange(LiveRange(UseIndex, EndIndex, RetVNI));
     
     // FIXME: Need to set kills properly for inter-block stuff.
-    if (RetVNI->isKill(UseIndex)) RetVNI->removeKill(UseIndex);
-    if (IsIntraBlock)
-      RetVNI->addKill(EndIndex);
   } else if (ContainsDefs && ContainsUses) {
     SmallPtrSet<MachineInstr*, 2>& BlockDefs = Defs[MBB];
     SmallPtrSet<MachineInstr*, 2>& BlockUses = Uses[MBB];
@@ -556,12 +553,6 @@ PreAllocSplitting::PerformPHIConstruction(MachineBasicBlock::iterator UseI,
                                       NewVNs, LiveOut, Phis, false, true);
 
     LI->addRange(LiveRange(StartIndex, EndIndex, RetVNI));
-    
-    if (foundUse && RetVNI->isKill(StartIndex))
-      RetVNI->removeKill(StartIndex);
-    if (IsIntraBlock) {
-      RetVNI->addKill(EndIndex);
-    }
   }
   
   // Memoize results so we don't have to recompute them.
@@ -636,9 +627,6 @@ PreAllocSplitting::PerformPHIConstructionFallBack(MachineBasicBlock::iterator Us
     for (DenseMap<MachineBasicBlock*, VNInfo*>::iterator I =
            IncomingVNs.begin(), E = IncomingVNs.end(); I != E; ++I) {
       I->second->setHasPHIKill(true);
-      SlotIndex KillIndex(LIs->getMBBEndIdx(I->first), true);
-      if (!I->second->isKill(KillIndex))
-        I->second->addKill(KillIndex);
     }
   }
       
@@ -648,8 +636,6 @@ PreAllocSplitting::PerformPHIConstructionFallBack(MachineBasicBlock::iterator Us
   } else
     EndIndex = LIs->getMBBEndIdx(MBB);
   LI->addRange(LiveRange(StartIndex, EndIndex, RetVNI));
-  if (IsIntraBlock)
-    RetVNI->addKill(EndIndex);
 
   // Memoize results so we don't have to recompute them.
   if (!IsIntraBlock)
@@ -725,25 +711,6 @@ void PreAllocSplitting::ReconstructLiveInterval(LiveInterval* LI) {
     
     VNInfo* DeadVN = NewVNs[&*DI];
     LI->addRange(LiveRange(DefIdx, DefIdx.getNextSlot(), DeadVN));
-    DeadVN->addKill(DefIdx);
-  }
-
-  // Update kill markers.
-  for (LiveInterval::vni_iterator VI = LI->vni_begin(), VE = LI->vni_end();
-       VI != VE; ++VI) {
-    VNInfo* VNI = *VI;
-    for (unsigned i = 0, e = VNI->kills.size(); i != e; ++i) {
-      SlotIndex KillIdx = VNI->kills[i];
-      if (KillIdx.isPHI())
-        continue;
-      MachineInstr *KillMI = LIs->getInstructionFromIndex(KillIdx);
-      if (KillMI) {
-        MachineOperand *KillMO = KillMI->findRegisterUseOperand(CurrLI->reg);
-        if (KillMO)
-          // It could be a dead def.
-          KillMO->setIsKill();
-      }
-    }
   }
 }
 
@@ -773,19 +740,14 @@ void PreAllocSplitting::RenumberValno(VNInfo* VN) {
     VNsToCopy.push_back(OldVN);
     
     // Locate two-address redefinitions
-    for (VNInfo::KillSet::iterator KI = OldVN->kills.begin(),
-         KE = OldVN->kills.end(); KI != KE; ++KI) {
-      assert(!KI->isPHI() &&
-             "VN previously reported having no PHI kills.");
-      MachineInstr* MI = LIs->getInstructionFromIndex(*KI);
-      unsigned DefIdx = MI->findRegisterDefOperandIdx(CurrLI->reg);
-      if (DefIdx == ~0U) continue;
-      if (MI->isRegTiedToUseOperand(DefIdx)) {
-        VNInfo* NextVN =
-          CurrLI->findDefinedVNInfoForRegInt(KI->getDefIndex());
-        if (NextVN == OldVN) continue;
+    for (MachineRegisterInfo::def_iterator DI = MRI->def_begin(CurrLI->reg),
+         DE = MRI->def_end(); DI != DE; ++DI) {
+      if (!DI->isRegTiedToUseOperand(DI.getOperandNo())) continue;
+      SlotIndex DefIdx = LIs->getInstructionIndex(&*DI).getDefIndex();
+      VNInfo* NextVN = CurrLI->findDefinedVNInfoForRegInt(DefIdx);
+      if (std::find(VNsToCopy.begin(), VNsToCopy.end(), NextVN) !=
+          VNsToCopy.end())
         Stack.push_back(NextVN);
-      }
     }
   }