After a basic block is split into two parts,
second part dominates all the blocks dominated
by original basic block. And first part dominates
second part.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40035 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/BasicBlockUtils.cpp b/lib/Transforms/Utils/BasicBlockUtils.cpp
index 520cfeb..0ed3ed6 100644
--- a/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -165,8 +165,21 @@
if (Loop *L = LI.getLoopFor(Old))
L->addBasicBlockToLoop(New, LI);
- if (DominatorTree *DT = P->getAnalysisToUpdate<DominatorTree>())
- DT->addNewBlock(New, Old);
+ if (DominatorTree *DT = P->getAnalysisToUpdate<DominatorTree>())
+ {
+ // Old dominates New. New node domiantes all other nodes dominated by Old.
+ DomTreeNode *OldNode = DT->getNode(Old);
+ std::vector<DomTreeNode *> Children;
+ for (DomTreeNode::iterator I = OldNode->begin(), E = OldNode->end();
+ I != E; ++I)
+ Children.push_back(*I);
+
+ DomTreeNode *NewNode = DT->addNewBlock(New,Old);
+
+ for (std::vector<DomTreeNode *>::iterator I = Children.begin(),
+ E = Children.end(); I != E; ++I)
+ DT->changeImmediateDominator(*I, NewNode);
+ }
if (DominanceFrontier *DF = P->getAnalysisToUpdate<DominanceFrontier>())
DF->splitBlock(Old);