Don't die with an assertion if the Result bitwidth is already correct.  This
fixes an assert reading "1239123123123123" when the result is already 64-bit.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155329 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/StringRef.cpp b/lib/Support/StringRef.cpp
index 14d314b..97af0ff 100644
--- a/lib/Support/StringRef.cpp
+++ b/lib/Support/StringRef.cpp
@@ -391,7 +391,7 @@
   unsigned BitWidth = Log2Radix * Str.size();
   if (BitWidth < Result.getBitWidth())
     BitWidth = Result.getBitWidth(); // don't shrink the result
-  else
+  else if (BitWidth > Result.getBitWidth())
     Result = Result.zext(BitWidth);
 
   APInt RadixAP, CharAP; // unused unless !IsPowerOf2Radix