Fix MSVC "result of 32-bit shift implicitly converted to 64 bits" warning. NFCI.

llvm-svn: 372308
diff --git a/llvm/lib/Target/ARM/ARMBasicBlockInfo.h b/llvm/lib/Target/ARM/ARMBasicBlockInfo.h
index 958e60e..18e7195 100644
--- a/llvm/lib/Target/ARM/ARMBasicBlockInfo.h
+++ b/llvm/lib/Target/ARM/ARMBasicBlockInfo.h
@@ -31,7 +31,7 @@
 /// @param KnownBits Number of known low offset bits.
 inline unsigned UnknownPadding(llvm::Align Align, unsigned KnownBits) {
   if (KnownBits < Log2(Align))
-    return Align.value() - (1u << KnownBits);
+    return Align.value() - (1ull << KnownBits);
   return 0;
 }