[llvm-commits] [llvm] r85671 - /llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp

[Chris Lattner]

Author: lattner
Date: Sat Oct 31 12:48:31 2009
New Revision: 85671

URL: http://llvm.org/viewvc/llvm-project?rev=85671&view=rev
Log:
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Modified:
    llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=85671&r1=85670&r2=85671&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Sat Oct 31 12:48:31 2009
@@ -10998,6 +10998,10 @@
         PN.setIncomingValue(i, VB);
         PN.setIncomingBlock(j, BBA);
         PN.setIncomingValue(j, VA);
+        // NOTE: Instcombine normally would want us to "return &PN" if we
+        // modified any of the operands of an instruction.  However, since we
+        // aren't adding or removing uses (just rearranging them) we don't do
+        // this in this case.
       }
     }