Don't potentially read past the end of the fill data when making a NaN from
an APInt.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97467 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/APFloat.cpp b/lib/Support/APFloat.cpp
index 16a0c23..619f061 100644
--- a/lib/Support/APFloat.cpp
+++ b/lib/Support/APFloat.cpp
@@ -638,7 +638,8 @@
   if (!fill || fill->getNumWords() < numParts)
     APInt::tcSet(significand, 0, numParts);
   if (fill) {
-    APInt::tcAssign(significand, fill->getRawData(), partCount());
+    APInt::tcAssign(significand, fill->getRawData(),
+                    std::min(fill->getNumWords(), numParts));
 
     // Zero out the excess bits of the significand.
     unsigned bitsToPreserve = semantics->precision - 1;