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authorJoseph Myers <joseph@codesourcery.com>2012-07-26 11:31:35 +0000
committerJoseph Myers <joseph@codesourcery.com>2012-07-26 11:31:35 +0000
commitda865e95bcf9a5365de78fa6b5c681aca0a1bb46 (patch)
tree783e2a5f2befa846dc208ec14b7dcde164c7b205 /math/s_clogl.c
parent3129cfc6ec7be65a0bdc1f82432ee421c1c65a77 (diff)
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Improve clog, clog10 handling of values with real or imaginary part 1 (bug 13629).
Diffstat (limited to 'math/s_clogl.c')
-rw-r--r--math/s_clogl.c29
1 files changed, 20 insertions, 9 deletions
diff --git a/math/s_clogl.c b/math/s_clogl.c
index a393b88a5f..d98a3c02c1 100644
--- a/math/s_clogl.c
+++ b/math/s_clogl.c
@@ -41,21 +41,21 @@ __clogl (__complex__ long double x)
{
/* Neither real nor imaginary part is NaN. */
long double absx = fabsl (__real__ x), absy = fabsl (__imag__ x);
- long double d;
int scale = 0;
+ if (absx < absy)
+ {
+ long double t = absx;
+ absx = absy;
+ absy = t;
+ }
+
if (absx > LDBL_MAX / 2.0L)
{
scale = -1;
absx = __scalbnl (absx, scale);
absy = (absy >= LDBL_MIN * 2.0L ? __scalbnl (absy, scale) : 0.0L);
}
- else if (absy > LDBL_MAX / 2.0L)
- {
- scale = -1;
- absx = (absx >= LDBL_MIN * 2.0L ? __scalbnl (absx, scale) : 0.0L);
- absy = __scalbnl (absy, scale);
- }
else if (absx < LDBL_MIN && absy < LDBL_MIN)
{
scale = LDBL_MANT_DIG;
@@ -63,9 +63,20 @@ __clogl (__complex__ long double x)
absy = __scalbnl (absy, scale);
}
- d = __ieee754_hypotl (absx, absy);
+ if (absx == 1.0L && scale == 0)
+ {
+ long double absy2 = absy * absy;
+ if (absy2 <= LDBL_MIN * 2.0L)
+ __real__ result = absy2 / 2.0L - absy2 * absy2 / 4.0L;
+ else
+ __real__ result = __log1pl (absy2) / 2.0L;
+ }
+ else
+ {
+ long double d = __ieee754_hypotl (absx, absy);
+ __real__ result = __ieee754_logl (d) - scale * M_LN2l;
+ }
- __real__ result = __ieee754_logl (d) - scale * M_LN2l;
__imag__ result = __ieee754_atan2l (__imag__ x, __real__ x);
}
else