[llvm-commits] [llvm] r138449 - /llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp

[Rafael Espindola]

Author: rafael
Date: Wed Aug 24 13:07:01 2011
New Revision: 138449

URL: http://llvm.org/viewvc/llvm-project?rev=138449&view=rev
Log:
Fix a crashing bug in SplitBlock when it is called on a block with no
dominator information even though dominators were previously computed.

Patch by Nick Sumner.

Modified:
    llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp

Modified: llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp?rev=138449&r1=138448&r2=138449&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/BasicBlockUtils.cpp Wed Aug 24 13:07:01 2011
@@ -299,16 +299,17 @@
 
   if (DominatorTree *DT = P->getAnalysisIfAvailable<DominatorTree>()) {
     // Old dominates New. New node dominates 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);
+    if (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);
+    }
   }
 
   return New;