[llvm-commits] [llvm] r114996 - /llvm/trunk/lib/VMCore/Metadata.cpp

[Dan Gohman]

Author: djg
Date: Tue Sep 28 17:07:19 2010
New Revision: 114996

URL: http://llvm.org/viewvc/llvm-project?rev=114996&view=rev
Log:
When an MDNode changes to become identical to another MDNode,
delete the MDNode that changed, rather than the other MDNode.
This is less work, because it doesn't require the changed node
to be re-inserted into the uniquing map and it doesn't require
the is-function-local flag to be recomputed. Also, it avoids
trouble when the existing node is part of a complicated
data structure.

Modified:
    llvm/trunk/lib/VMCore/Metadata.cpp

Modified: llvm/trunk/lib/VMCore/Metadata.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/Metadata.cpp?rev=114996&r1=114995&r2=114996&view=diff
==============================================================================
--- llvm/trunk/lib/VMCore/Metadata.cpp (original)
+++ llvm/trunk/lib/VMCore/Metadata.cpp Tue Sep 28 17:07:19 2010
@@ -339,15 +339,14 @@
 
   // Now that the node is out of the folding set, get ready to reinsert it.
   // First, check to see if another node with the same operands already exists
-  // in the set.  If it doesn't exist, this returns the position to insert it.
+  // in the set.  If so, then this node is redundant.
   FoldingSetNodeID ID;
   Profile(ID);
   void *InsertPoint;
   if (MDNode *N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint)) {
-    N->replaceAllUsesWith(this);
-    N->destroy();
-    N = pImpl->MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
-    assert(N == 0 && "shouldn't be in the map now!"); (void)N;
+    replaceAllUsesWith(N);
+    destroy();
+    return;
   }
 
   // InsertPoint will have been set by the FindNodeOrInsertPos call.