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authorJoseph Myers <joseph@codesourcery.com>2016-05-26 22:58:36 +0000
committerJoseph Myers <joseph@codesourcery.com>2016-05-26 22:58:36 +0000
commit98c9c9d9ca6c1eb8e30fe449b1e1121b8c498715 (patch)
tree3d8ac5444e4c4bbe885f4ca0bd9327aa02d0a3b6 /sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c
parentd73e7bdb3a9284eb437b6cd84923658e25f922f2 (diff)
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Fix ldbl-128ibm sqrtl (sNaN) (bug 20153).
The ldbl-128ibm implementation of sqrtl wrongly returns an sNaN for signaling NaN arguments. This patch fixes it to quiet its argument, using the same x * x + x return for infinities and NaNs as the dbl-64 implementation uses to ensure that +Inf maps to +Inf while -Inf and NaN map to NaN. Tested for powerpc. [BZ #20153] * sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c (__ieee754_sqrtl): Return x * x + x for infinities and NaNs.
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c8
1 files changed, 3 insertions, 5 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c b/sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c
index 96845fe..51365d6 100644
--- a/sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/e_sqrtl.c
@@ -91,11 +91,9 @@ long double __ieee754_sqrtl(long double x)
return c.x * i;
}
else {
- if (k>=INT64_C(0x7ff0000000000000)) {
- if (a.i[0] == INT64_C(0xfff0000000000000))
- return (big1-big1)/(big-big); /* sqrt (-Inf) = NaN. */
- return x; /* sqrt (NaN) = NaN, sqrt (+Inf) = +Inf. */
- }
+ if (k>=INT64_C(0x7ff0000000000000))
+ /* sqrt (-Inf) = NaN, sqrt (NaN) = NaN, sqrt (+Inf) = +Inf. */
+ return x * x + x;
if (x == 0) return x;
if (x < 0) return (big1-big1)/(big-big);
return tm256*__ieee754_sqrtl(x*t512);