Mercurial > mxe-octave

comparison src/build-msvctools/math/expm1.c @ 3061:f8299bb6c872

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Initial support for native MSVC compilation. * add MSVC support files: compiler wrappers and support libraries * adapt libiconv to work with MSVC * adapt gettext to work with MSVC
author Michael Goffioul <michael.goffioul@gmail.com>
date Mon, 17 Jun 2013 22:43:11 -0400
parents
children
comparison
equal deleted inserted replaced
3060:cbdf4575016d 3061:f8299bb6c872
1 /*
2 * Written 2005 by Gregory W. Chicares <chicares@cox.net>.
3 * Adapted to double by Danny Smith <dannysmith@users.sourceforge.net>.
4 * Public domain.
5 *
6 * F2XM1's input is constrained to (-1, +1), so the domain of
7 * 'x * LOG2EL' is (-LOGE2L, +LOGE2L). Outside that domain,
8 * delegating to exp() handles C99 7.12.6.3/2 range errors.
9 *
10 * Constants from moshier.net, file cephes/ldouble/constl.c,
11 * are used instead of M_LN2 and M_LOG2E, which would not be
12 * visible with 'gcc std=c99'. The use of these extended precision
13 * constants also allows gcc to replace them with x87 opcodes.
14 */
15
16 #include <math.h> /* expl() */
17 #include "cephes_mconf.h"
18 double expm1 (double x)
19 {
20 if (fabs(x) < LOGE2L)
21 {
22 x *= LOG2EL;
23 __asm__("f2xm1" : "=t" (x) : "0" (x));
24 return x;
25 }
26 else
27 return exp(x) - 1.0;
28 }