diff options
Diffstat (limited to 'lib/CodeGen/PreAllocSplitting.cpp')
| -rw-r--r-- | lib/CodeGen/PreAllocSplitting.cpp | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/lib/CodeGen/PreAllocSplitting.cpp b/lib/CodeGen/PreAllocSplitting.cpp index a538db8be0..99fdb840cc 100644 --- a/lib/CodeGen/PreAllocSplitting.cpp +++ b/lib/CodeGen/PreAllocSplitting.cpp @@ -654,8 +654,24 @@ PreAllocSplitting::PerformPHIConstructionFallBack(MachineBasicBlock::iterator Us } if (MBB->pred_size() == 1 && !RetVNI->hasPHIKill) { - LI->MergeValueNumberInto(RetVNI, IncomingVNs.begin()->second); - Phis[MBB] = RetVNI = IncomingVNs.begin()->second; + VNInfo* OldVN = RetVNI; + VNInfo* NewVN = IncomingVNs.begin()->second; + VNInfo* MergedVN = LI->MergeValueNumberInto(OldVN, NewVN); + if (MergedVN == OldVN) std::swap(OldVN, NewVN); + + for (DenseMap<MachineBasicBlock*, VNInfo*>::iterator LOI = LiveOut.begin(), + LOE = LiveOut.end(); LOI != LOE; ++LOI) + if (LOI->second == OldVN) + LOI->second = MergedVN; + for (DenseMap<MachineInstr*, VNInfo*>::iterator NVI = NewVNs.begin(), + NVE = NewVNs.end(); NVI != NVE; ++NVI) + if (NVI->second == OldVN) + NVI->second = MergedVN; + for (DenseMap<MachineBasicBlock*, VNInfo*>::iterator PI = Phis.begin(), + PE = Phis.end(); PI != PE; ++PI) + if (PI->second == OldVN) + PI->second = MergedVN; + RetVNI = MergedVN; } else { // Otherwise, merge the incoming VNInfos with a phi join. Create a new // VNInfo to represent the joined value. |