glibc/sysdeps/ieee754/ldbl-128/e_gammal_r.c
Ulrich Drepper 52e1b618f4 Update.
2002-07-03  Jakub Jelinek  <jakub@redhat.com>

	* stdio-common/printf_fp.c (__printf_fp.c): If _FPIO_CONST_SHIFT is
	non-zero, adjust exponent.
	* sysdeps/ieee754/ldbl-128/s_erfl.c (__erfl, erfl, __erfcl, erfcl):
	Remove NO_LONG_DOUBLE aliases.
	* sysdeps/ieee754/ldbl-128/s_expm1l.c (__expm1l, expm1l): Likewise.
	* sysdeps/ieee754/ldbl-128/s_log1pl.c (__log1pl, log1pl): Likewise.
	(__log1pl): Raise divide by zero and invalid exceptions when needed.
	* sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Special case
	1**y and -1**+-Inf.
	* sysdeps/ieee754/ldbl-128/ldbl2mpn.c (__mpn_extract_long_double):
	Fix BITS_PER_MP_LIMB 32 extraction.
	* sysdeps/ieee754/ldbl-128/e_log2l.c (__ieee754_log2l): Don't raise
	exceptions for qNaNs.
	* sysdeps/ieee754/ldbl-128/e_log10l.c (__ieee754_log10l): Likewise.
	* sysdeps/ieee754/ldbl-128/e_lgammal_r.c (__ieee754_lgamma_r):
	Raise exceptions when needed.  Don't recurse unnecessarily.
	Special case 1.0L and 2.0L arguments to avoid -0.0L as result.
	* sysdeps/ieee754/ldbl-128/e_j0l.c (__ieee754_y0l): Don't raise
	exceptions for qNaNs.
	* sysdeps/ieee754/ldbl-128/s_remquol.c (__remquol): Make qs 64-bit
	to fix *quo return value sign.
	* sysdeps/ieee754/ldbl-128/e_gammal_r.c (__ieee754_gamma_r): Special
	case -Inf argument.
	* soft-fp/op-4.h (_FP_FRAC_CLZ_4): Fix a pasto.

2002-07-01  Jakub Jelinek  <jakub@redhat.com>

	* libio/tst-eof.c (do_test): Remove unused ch and tm variables.
	* iconvdata/iso-2022-jp-3.c (EMIT_SHIFT_TO_INIT): Kill warnings if
	-DNDEBUG.
2002-07-11 05:55:13 +00:00

59 lines
2.0 KiB
C

/* Implementation of gamma function according to ISO C.
Copyright (C) 1997, 1999, 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
Jakub Jelinek <jj@ultra.linux.cz, 1999.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <math.h>
#include <math_private.h>
long double
__ieee754_gammal_r (long double x, int *signgamp)
{
/* We don't have a real gamma implementation now. We'll use lgamma
and the exp function. But due to the required boundary
conditions we must check some values separately. */
int64_t hx;
u_int64_t lx;
GET_LDOUBLE_WORDS64 (hx, lx, x);
if (((hx & 0x7fffffffffffffffLL) | lx) == 0)
{
/* Return value for x == 0 is NaN with invalid exception. */
*signgamp = 0;
return x / x;
}
if (hx < 0 && (u_int64_t) hx < 0xffff000000000000ULL && __rintl (x) == x)
{
/* Return value for integer x < 0 is NaN with invalid exception. */
*signgamp = 0;
return (x - x) / (x - x);
}
if (hx == 0xffff000000000000ULL && lx == 0)
{
/* x == -Inf. According to ISO this is NaN. */
*signgamp = 0;
return x - x;
}
/* XXX FIXME. */
return __ieee754_expl (__ieee754_lgammal_r (x, signgamp));
}