[llvm-commits] [llvm] r112351 - /llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp

[Chris Lattner]

Author: lattner
Date: Fri Aug 27 22:36:51 2010
New Revision: 112351

URL: http://llvm.org/viewvc/llvm-project?rev=112351&view=rev
Log:
for completeness, allow undef also.

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp?rev=112351&r1=112350&r2=112351&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp Fri Aug 27 22:36:51 2010
@@ -1381,6 +1381,9 @@
 static bool CollectInsertionElements(Value *V, unsigned ElementIndex,
                                      SmallVectorImpl<Value*> &Elements,
                                      const Type *VecEltTy) {
+  // Undef values never contribute useful bits to the result.
+  if (isa<UndefValue>(V)) return true;
+  
   // If we got down to a value of the right type, we win, try inserting into the
   // right element.
   if (V->getType() == VecEltTy) {