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Re: [PATCH] Update sparc ULPs.
From: "Joseph S. Myers" <joseph@codesourcery.com>
Date: Fri, 16 Nov 2012 17:40:10 +0000
> Those indicate that ldbl-128 needs a fix for bug 14811 (probably similar
> to those for other versions, i.e. saturating small exponents to +/-
> 0x1p-128, but each version of pow is substantially different from the
> others).
The following patch seems to do the trick, does it look OK to you?
2012-11-16 David S. Miller <davem@davemloft.net>
[BZ #14811]
* sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Saturate
nonzero exponents with absolute value below 0x1p-128 to +/-
0x1p-128.
diff --git a/sysdeps/ieee754/ldbl-128/e_powl.c b/sysdeps/ieee754/ldbl-128/e_powl.c
index 40fc314..d131750 100644
--- a/sysdeps/ieee754/ldbl-128/e_powl.c
+++ b/sysdeps/ieee754/ldbl-128/e_powl.c
@@ -149,7 +149,7 @@ __ieee754_powl (long double x, long double y)
{
long double z, ax, z_h, z_l, p_h, p_l;
long double y1, t1, t2, r, s, t, u, v, w;
- long double s2, s_h, s_l, t_h, t_l;
+ long double s2, s_h, s_l, t_h, t_l, ay;
int32_t i, j, k, yisint, n;
u_int32_t ix, iy;
int32_t hx, hy;
@@ -282,6 +282,10 @@ __ieee754_powl (long double x, long double y)
return (hy > 0) ? huge * huge : tiny * tiny;
}
+ ay = y > 0 ? y : -y;
+ if (ay < 0x1p-128)
+ y = y < 0 ? -0x1p-128 : 0x1p-128;
+
n = 0;
/* take care subnormal number */
if (ix < 0x00010000)