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mirror of git://sourceware.org/git/newlib-cygwin.git synced 2025-01-14 17:59:28 +08:00
Thomas Fitzsimmons 60565ed657 2001-12-18 Thomas Fitzsimmons <fitzsim@redhat.com>
* libc/machine/i386/f_*: Move to libm/machine/i386.

2001-12-18      Joel Sherrill <joel@OARcorp.com>

	* libm/machine/Makefile.am: Add dummy doc stub so
	"make info" works.

2001-12-17	Joel Sherrill <joel@OARcorp.com>

	* libc/include/sys/types.h (ino_t): RTEMS uses long also.
2001-12-19 03:03:43 +00:00

48 lines
1.1 KiB
C

/*
* ====================================================
* Copyright (C) 1998 by Cygnus Solutions. All rights reserved.
*
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#if !defined(_SOFT_FLOAT)
/*
Fast version of exp using Intel float instructions.
double _f_exp (double x);
Function computes e ** x. The following special cases exist:
1. if x is 0.0 ==> return 1.0
2. if x is infinity ==> return infinity
3. if x is -infinity ==> return 0.0
4. if x is NaN ==> return x
There is no error checking or setting of errno.
*/
#include <math.h>
#include <ieeefp.h>
#include "f_math.h"
double _f_exp (double x)
{
if (check_finite(x))
{
double result;
asm ("fldl2e; fmulp; fld %%st; frndint; fsub %%st,%%st(1); fxch;" \
"fchs; f2xm1; fld1; faddp; fxch; fld1; fscale; fstp %%st(1); fmulp" :
"=t"(result) : "0"(x));
return result;
}
else if (x == -infinity())
return 0.0;
return x;
}
#endif