Fixed an assertion failure for tracking sext of a vector of integers


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90290 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index 31d3ccc..22c6e3b 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -659,7 +659,7 @@
   switch (Operator::getOpcode(V)) {
   default: break;
   case Instruction::SExt:
-    Tmp = TyBits-cast<IntegerType>(U->getOperand(0)->getType())->getBitWidth();
+    Tmp = TyBits - U->getOperand(0)->getType()->getScalarSizeInBits();
     return ComputeNumSignBits(U->getOperand(0), TD, Depth+1) + Tmp;
     
   case Instruction::AShr: