Fix a bug that was found by building clang with -fsanitize.
I introduced it in r166785. PR14291.

If TD is unavailable use getScalarSizeInBits, but don't optimize
pointers or vectors of pointers.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170586 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index 64e132e..5421cbe 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -433,7 +433,12 @@
     unsigned SrcBitWidth;
     // Note that we handle pointer operands here because of inttoptr/ptrtoint
     // which fall through here.
-    SrcBitWidth = TD->getTypeSizeInBits(SrcTy->getScalarType());
+    if(TD) {
+      SrcBitWidth = TD->getTypeSizeInBits(SrcTy->getScalarType());
+    } else {
+      SrcBitWidth = SrcTy->getScalarSizeInBits();
+      if (!SrcBitWidth) return;
+    }
 
     assert(SrcBitWidth && "SrcBitWidth can't be zero");
     KnownZero = KnownZero.zextOrTrunc(SrcBitWidth);