Fix PR5563, an expensive checks failure when running on

tests/Transforms/InstCombine/shufflemask-undef.ll.  If
anyone cares, the use of 2*e here (and the equivalent
all over the place in instcombine) seems wrong, though
harmless: it should really be twice the length of the
input vector.  I think shufflevector used to require
that the mask have the same length as the input, but I
don't think that's true any more.  I don't care enough
about vectors to do anything about this...

llvm-svn: 89456

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
index 1c48366e89f..6f74902e1b4 100644
--- a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -12920,7 +12920,7 @@ Instruction *InstCombiner::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
       if (LHSMask.size() == Mask.size()) {
         std::vector<unsigned> NewMask;
         for (unsigned i = 0, e = Mask.size(); i != e; ++i)
-          if (Mask[i] >= 2*e)
+          if (Mask[i] >= e)
             NewMask.push_back(2*e);
           else
             NewMask.push_back(LHSMask[Mask[i]]);