diff options
Diffstat (limited to 'lib/CodeGen/StrongPHIElimination.cpp')
| -rw-r--r-- | lib/CodeGen/StrongPHIElimination.cpp | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/lib/CodeGen/StrongPHIElimination.cpp b/lib/CodeGen/StrongPHIElimination.cpp index e5cae2bc72..ff58e796bf 100644 --- a/lib/CodeGen/StrongPHIElimination.cpp +++ b/lib/CodeGen/StrongPHIElimination.cpp @@ -550,7 +550,9 @@ void StrongPHIElimination::processPHIUnion(MachineInstr* Inst, for (DomForestNode::iterator CI = DFNode->begin(), CE = DFNode->end(); CI != CE; ++CI) { DomForestNode* child = *CI; - + + // If the current node is live-out of the defining block of one of its + // children, insert a copy for it if (isLiveOut(DFNode->getReg(), MRI.getVRegDef(child->getReg())->getParent(), MRI, LV)) { // Insert copies for parent @@ -565,6 +567,9 @@ void StrongPHIElimination::processPHIUnion(MachineInstr* Inst, PHIUnion.erase(SrcReg); } } + + // If a node is live-in to the defining block of one of its children, but + // not live-out, then we need to scan that block for local interferences. } else if (isLiveIn(DFNode->getReg(), MRI.getVRegDef(child->getReg())->getParent(), MRI, LV) || |