gcc/libgcc-math/dbl-64/slowexp.c
Richard Guenther 0058967bb0 Makefile.def (target_modules): Add libgcc-math target module.
2006-01-31  Richard Guenther  <rguenther@suse.de>
	Paolo Bonzini  <bonzini@gnu.org>

	* Makefile.def (target_modules): Add libgcc-math target module.
	* configure.in (target_libraries): Add libgcc-math target library.
	(--enable-libgcc-math): New configure switch.
	* Makefile.in: Re-generate.
	* configure: Re-generate.
	* libgcc-math: New toplevel directory.

	* doc/install.texi (--disable-libgcc-math): Document.

	libgcc-math/
	* configure.ac: New file.
	* Makefile.am: Likewise.
	* configure: New generated file.
	* Makefile.in: Likewise.
	* aclocal.m4: Likewise.
	* libtool-version: New file.
	* include/ieee754.h: New file.
	* include/libc-symbols.h: Likewise.
	* include/math_private.h: Likewise.
	* i386/Makefile.am: New file.
	* i386/Makefile.in: New generated file.
	* i386/sse2.h: New file.
	* i386/endian.h: Likewise.
	* i386/sse2.map: Linker script for SSE2 ABI math intrinsics.
	* flt-32/: Import from glibc.
	* dbl-64/: Likewise.

Co-Authored-By: Paolo Bonzini <bonzini@gnu.org>

From-SVN: r110434
2006-01-31 11:56:46 +00:00

66 lines
2.6 KiB
C

/*
* IBM Accurate Mathematical Library
* written by International Business Machines Corp.
* Copyright (C) 2001 Free Software Foundation
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/**************************************************************************/
/* MODULE_NAME:slowexp.c */
/* */
/* FUNCTION:slowexp */
/* */
/* FILES NEEDED:mpa.h */
/* mpa.c mpexp.c */
/* */
/*Converting from double precision to Multi-precision and calculating */
/* e^x */
/**************************************************************************/
#include "mpa.h"
#include "math_private.h"
void __mpexp(mp_no *x, mp_no *y, int p);
/*Converting from double precision to Multi-precision and calculating e^x */
double __slowexp(double x) {
double w,z,res,eps=3.0e-26;
#if 0
double y;
#endif
int p;
#if 0
int orig,i;
#endif
mp_no mpx, mpy, mpz,mpw,mpeps,mpcor;
p=6;
__dbl_mp(x,&mpx,p); /* Convert a double precision number x */
/* into a multiple precision number mpx with prec. p. */
__mpexp(&mpx, &mpy, p); /* Multi-Precision exponential function */
__dbl_mp(eps,&mpeps,p);
__mul(&mpeps,&mpy,&mpcor,p);
__add(&mpy,&mpcor,&mpw,p);
__sub(&mpy,&mpcor,&mpz,p);
__mp_dbl(&mpw, &w, p);
__mp_dbl(&mpz, &z, p);
if (w == z) return w;
else { /* if calculating is not exactly */
p = 32;
__dbl_mp(x,&mpx,p);
__mpexp(&mpx, &mpy, p);
__mp_dbl(&mpy, &res, p);
return res;
}
}