X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Flogl.c;h=0c00a2b22857aaedc34d8f5a196a859461b9452b;hb=fa1db0dd22768f09a507674a30beb5b8a87bb35f;hp=16053cf3f3fcea3212c79bd16592c87cb3a3e066;hpb=55eed6bbc87934f2db04981e6f0f1773ff77974f;p=gnulib.git diff --git a/lib/logl.c b/lib/logl.c index 16053cf3f..0c00a2b22 100644 --- a/lib/logl.c +++ b/lib/logl.c @@ -1,9 +1,9 @@ /* Copyright 2001 by Stephen L. Moshier - This program is free software; you can redistribute it and/or modify + This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2, or (at your option) - any later version. + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -11,16 +11,39 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; see the file COPYING. - If not, write to the Free Software Foundation, - 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + along with this program. If not, see . */ #include /* Specification. */ #include -/* logll.c +#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE + +long double +logl (long double x) +{ + return log (x); +} + +#elif HAVE_LOGL + +long double +logl (long double x) +# undef logl +{ + /* Work around the OSF/1 5.1 bug. */ + if (x == 0.0L) + /* Return -Infinity. */ + return -1.0L / 0.0L; + return logl (x); +} + +#else + +/* Code based on glibc/sysdeps/ieee754/ldbl-128/e_logl.c. */ + +/* logll.c * * Natural logarithm for 128-bit long double precision. * @@ -64,8 +87,6 @@ * */ -#include "isnanl.h" - /* log(1+x) = x - .5 x^2 + x^3 l(x) -.0078125 <= x <= +.0078125 peak relative error 1.2e-37 */ @@ -126,7 +147,7 @@ static const long double logtbl[92] = { -2.7902661731604211834685052867305795169688E-4L, -1.2335696813916860754951146082826952093496E-4L, -3.0677461025892873184042490943581654591817E-5L, -#define ZERO logtbl[38] +# define ZERO logtbl[38] 0.0000000000000000000000000000000000000000E0L, -3.0359557945051052537099938863236321874198E-5L, -1.2081346403474584914595395755316412213151E-4L, @@ -189,11 +210,10 @@ static const long double ln2b = 1.4286068203094172321214581765680755001344E-6L; long double -logl(long double x) +logl (long double x) { long double z, y, w; - long double u, t; - unsigned int m; + long double t; int k, e; /* Check for IEEE special cases. */ @@ -220,7 +240,7 @@ logl(long double x) } /* Extract exponent and reduce domain to 0.703125 <= u < 1.40625 */ - x = frexpl(x, &e); + x = frexpl (x, &e); if (x < 0.703125L) { x += x; @@ -244,17 +264,17 @@ logl(long double x) /* Series expansion of log(1+z). */ w = z * z; y = ((((((((((((l15 * z - + l14) * z - + l13) * z - + l12) * z - + l11) * z - + l10) * z - + l9) * z - + l8) * z - + l7) * z - + l6) * z - + l5) * z - + l4) * z + + l14) * z + + l13) * z + + l12) * z + + l11) * z + + l10) * z + + l9) * z + + l8) * z + + l7) * z + + l6) * z + + l5) * z + + l4) * z + l3) * z * w; y -= 0.5 * w; y += e * ln2b; /* Base 2 exponent offset times ln(2). */ @@ -264,3 +284,5 @@ logl(long double x) y += e * ln2a; return y; } + +#endif