lib/glibc
1
0
Fork 0
mirror of https://sourceware.org/git/glibc.git synced 2025-07-30 22:43:12 +03:00
Code Activity

Improve clog, clog10 handling of values with real or imaginary part 1 (bug 13629).

Browse Source
This commit is contained in:
Joseph Myers
2012-07-26 11:31:35 +00:00
parent 3129cfc6ec
commit da865e95bc
10 changed files with 318 additions and 54 deletions
Download Patch File Download Diff File Expand all files Collapse all files

38
math/s_clog10f.c
View File

@ -44,21 +44,21 @@ __clog10f (__complex__ float x)
{
/* Neither real nor imaginary part is NaN. */
float absx = fabsf (__real__ x), absy = fabsf (__imag__ x);
float d;
int scale = 0;
if (absx < absy)
{
float t = absx;
absx = absy;
absy = t;
}
if (absx > FLT_MAX / 2.0f)
{
scale = -1;
absx = __scalbnf (absx, scale);
absy = (absy >= FLT_MIN * 2.0f ? __scalbnf (absy, scale) : 0.0f);
}
else if (absy > FLT_MAX / 2.0f)
{
scale = -1;
absx = (absx >= FLT_MIN * 2.0f ? __scalbnf (absx, scale) : 0.0f);
absy = __scalbnf (absy, scale);
}
else if (absx < FLT_MIN && absy < FLT_MIN)
{
scale = FLT_MANT_DIG;
@ -66,9 +66,29 @@ __clog10f (__complex__ float x)
absy = __scalbnf (absy, scale);
}
d = __ieee754_hypotf (absx, absy);
if (absx == 1.0f && scale == 0)
{
float absy2 = absy * absy;
if (absy2 <= FLT_MIN * 2.0f * (float) M_LN10)
{
#if __FLT_EVAL_METHOD__ == 0
__real__ result
= (absy2 / 2.0f - absy2 * absy2 / 4.0f) * (float) M_LOG10E;
#else
volatile float force_underflow = absy2 * absy2 / 4.0f;
__real__ result
= (absy2 / 2.0f - force_underflow) * (float) M_LOG10E;
#endif
}
else
__real__ result = __log1pf (absy2) * ((float) M_LOG10E / 2.0f);
}
else
{
float d = __ieee754_hypotf (absx, absy);
__real__ result = __ieee754_log10f (d) - scale * M_LOG10_2f;
}
__real__ result = __ieee754_log10f (d) - scale * M_LOG10_2f;
__imag__ result = M_LOG10E * __ieee754_atan2f (__imag__ x, __real__ x);
}
else