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authorJoseph Myers <joseph@codesourcery.com>2012-03-02 15:32:56 +0000
committerJoseph Myers <joseph@codesourcery.com>2012-03-02 15:32:56 +0000
commita6d06d7b86f724046b462115556d0df682f9f703 (patch)
tree640870a7d978c8a224fe317e862b65fddba6f40e /sysdeps/ieee754/ldbl-128/s_scalbnl.c
parent07e12bb391ae84eb74817d42feda42cff7f687e5 (diff)
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Fix scalbn, scalbln integer overflow.
Diffstat (limited to 'sysdeps/ieee754/ldbl-128/s_scalbnl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128/s_scalbnl.c8
1 files changed, 5 insertions, 3 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_scalbnl.c b/sysdeps/ieee754/ldbl-128/s_scalbnl.c
index b9de0f74fc..a928ecccec 100644
--- a/sysdeps/ieee754/ldbl-128/s_scalbnl.c
+++ b/sysdeps/ieee754/ldbl-128/s_scalbnl.c
@@ -46,10 +46,12 @@ long double __scalbnl (long double x, int n)
 	    k = ((hx>>48)&0x7fff) - 114;
 	}
         if (k==0x7fff) return x+x;		/* NaN or Inf */
-        k = k+n;
-        if (n> 50000 || k > 0x7ffe)
-	  return huge*__copysignl(huge,x); /* overflow  */
 	if (n< -50000) return tiny*__copysignl(tiny,x); /*underflow*/
+        if (n> 50000 || k+n > 0x7ffe)
+	  return huge*__copysignl(huge,x); /* overflow  */
+	/* Now k and n are bounded we know that k = k+n does not
+	   overflow.  */
+        k = k+n;
         if (k > 0) 				/* normal result */
 	    {SET_LDOUBLE_MSW64(x,(hx&0x8000ffffffffffffULL)|(k<<48)); return x;}
         if (k <= -114)