2 files changed, 4 insertions, 25 deletions
diff --git a/llvm/lib/CodeGen/MachineBasicBlock.cpp b/llvm/lib/CodeGen/MachineBasicBlock.cpp
index ebf3be80257..18d034aeaa9 100644
--- a/llvm/lib/CodeGen/MachineBasicBlock.cpp
+++ b/llvm/lib/CodeGen/MachineBasicBlock.cpp
@@ -906,31 +906,8 @@ MachineBasicBlock::SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P) {
   }
 
   if (MachineDominatorTree *MDT =
-      P->getAnalysisIfAvailable<MachineDominatorTree>()) {
-    // Update dominator information.
-    MachineDomTreeNode *SucccDTNode = MDT->getNode(Succ);
-
-    bool IsNewIDom = true;
-    for (const_pred_iterator PI = Succ->pred_begin(), E = Succ->pred_end();
-         PI != E; ++PI) {
-      MachineBasicBlock *PredBB = *PI;
-      if (PredBB == NMBB)
-        continue;
-      if (!MDT->dominates(SucccDTNode, MDT->getNode(PredBB))) {
-        IsNewIDom = false;
-        break;
-      }
-    }
-
-    // We know "this" dominates the newly created basic block.
-    MachineDomTreeNode *NewDTNode = MDT->addNewBlock(NMBB, this);
-
-    // If all the other predecessors of "Succ" are dominated by "Succ" itself
-    // then the new block is the new immediate dominator of "Succ". Otherwise,
-    // the new block doesn't dominate anything.
-    if (IsNewIDom)
-      MDT->changeImmediateDominator(SucccDTNode, NewDTNode);
-  }
+      P->getAnalysisIfAvailable<MachineDominatorTree>())
+    MDT->recordSplitCriticalEdge(this, Succ, NMBB);
 
   if (MachineLoopInfo *MLI = P->getAnalysisIfAvailable<MachineLoopInfo>())
     if (MachineLoop *TIL = MLI->getLoopFor(this)) {
diff --git a/llvm/lib/CodeGen/MachineDominators.cpp b/llvm/lib/CodeGen/MachineDominators.cpp
index 04c8ecbf9bd..df60cf34b61 100644
--- a/llvm/lib/CodeGen/MachineDominators.cpp
+++ b/llvm/lib/CodeGen/MachineDominators.cpp
@@ -35,6 +35,8 @@ void MachineDominatorTree::getAnalysisUsage(AnalysisUsage &AU) const {
 }
 
 bool MachineDominatorTree::runOnMachineFunction(MachineFunction &F) {
+  CriticalEdgesToSplit.clear();
+  NewBBs.clear();
   DT->recalculate(F);
 
   return false;