From d44c6cc4776d38dcb91069a776904b307f634370 Mon Sep 17 00:00:00 2001
From: John McCall <rjmccall@apple.com>
Date: Mon, 1 Mar 2010 18:38:45 +0000
Subject: [PATCH] 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
---
 lib/Support/APFloat.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/Support/APFloat.cpp b/lib/Support/APFloat.cpp
index 16a0c232927..619f061862c 100644
--- a/lib/Support/APFloat.cpp
+++ b/lib/Support/APFloat.cpp
@@ -638,7 +638,8 @@ void APFloat::makeNaN(bool SNaN, bool Negative, const APInt *fill)
   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;