[llvm-commits] [llvm] r56316 - /llvm/trunk/lib/Transforms/Scalar/DCE.cpp

[Bill Wendling]

Author: void
Date: Thu Sep 18 18:04:18 2008
New Revision: 56316

URL: http://llvm.org/viewvc/llvm-project?rev=56316&view=rev
Log:
Decrementing the iterator here could be wrong if the worklist is empty after the "erase".
Thanks to Ji Young Park for the patch!

Modified:
    llvm/trunk/lib/Transforms/Scalar/DCE.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/DCE.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/DCE.cpp?rev=56316&r1=56315&r2=56316&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/DCE.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/DCE.cpp Thu Sep 18 18:04:18 2008
@@ -111,11 +111,12 @@
 
       // Remove the instruction from the worklist if it still exists in it.
       for (std::vector<Instruction*>::iterator WI = WorkList.begin();
-           WI != WorkList.end(); ++WI)
-        if (*WI == I) {
+           WI != WorkList.end(); ) {
+        if (*WI == I)
           WI = WorkList.erase(WI);
-          --WI;
-        }
+        else
+          ++WI;
+      }
 
       MadeChange = true;
       ++DCEEliminated;