glibc/sysdeps/m68k/m680x0/fpu/s_cexp.c
2014-02-10 20:22:40 +01:00

137 lines
3.6 KiB
C

/* Complex exponential function. m68k fpu version
Copyright (C) 1997-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
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, see
<http://www.gnu.org/licenses/>. */
#include <float.h>
#include <complex.h>
#include <math.h>
#include "mathimpl.h"
#ifndef SUFF
#define SUFF
#endif
#ifndef float_type
#define float_type double
#endif
#define CONCATX(a,b) __CONCAT(a,b)
#define s(name) CONCATX(name,SUFF)
#define m81(func) __m81_u(s(func))
__complex__ float_type
s(__cexp) (__complex__ float_type x)
{
__complex__ float_type retval;
unsigned long ix_cond;
ix_cond = __m81_test (__imag__ x);
if ((ix_cond & (__M81_COND_NAN|__M81_COND_INF)) == 0)
{
/* Imaginary part is finite. */
unsigned long rx_cond = __m81_test (__real__ x);
if ((rx_cond & (__M81_COND_NAN|__M81_COND_INF)) == 0)
{
const int t = (int) ((LDBL_MAX_EXP - 1) * M_LN2l);
long double sin_ix, cos_ix, exp_val;
__m81_u (__sincosl) (__imag__ x, &sin_ix, &cos_ix);
if (__real__ x > t)
{
long double exp_t = __m81_u(__ieee754_expl) (t);
__real__ x -= t;
sin_ix *= exp_t;
cos_ix *= exp_t;
if (__real__ x > t)
{
__real__ x -= t;
sin_ix *= exp_t;
cos_ix *= exp_t;
}
}
exp_val = __m81_u(__ieee754_expl) (__real__ x);
__real__ retval = exp_val * cos_ix;
if (ix_cond & __M81_COND_ZERO)
__imag__ retval = __imag__ x;
else
__imag__ retval = exp_val * sin_ix;
}
else
{
/* Compute the sign of the result. */
long double remainder, pi_2;
int quadrant;
if ((rx_cond & (__M81_COND_NAN|__M81_COND_NEG)) == __M81_COND_NEG)
__real__ retval = __imag__ retval = 0.0;
else
__real__ retval = __imag__ retval = __real__ x;
__asm ("fmovecr %#0,%0\n\tfscale%.w %#-1,%0" : "=f" (pi_2));
__asm ("fmod%.x %2,%0\n\tfmove%.l %/fpsr,%1"
: "=f" (remainder), "=dm" (quadrant)
: "f" (pi_2), "0" (__imag__ x));
quadrant = (quadrant >> 16) & 0x83;
if (quadrant & 0x80)
quadrant ^= 0x83;
switch (quadrant)
{
default:
break;
case 1:
__real__ retval = -__real__ retval;
break;
case 2:
__real__ retval = -__real__ retval;
case 3:
__imag__ retval = -__imag__ retval;
break;
}
if (ix_cond & __M81_COND_ZERO && (rx_cond & __M81_COND_NAN) == 0)
__imag__ retval = __imag__ x;
}
}
else
{
unsigned long rx_cond = __m81_test (__real__ x);
if (rx_cond & __M81_COND_INF)
{
/* Real part is infinite. */
if (rx_cond & __M81_COND_NEG)
{
__real__ retval = __imag__ retval = 0.0;
if (ix_cond & __M81_COND_NEG)
__imag__ retval = -__imag__ retval;
}
else
{
__real__ retval = __real__ x;
__imag__ retval = __imag__ x - __imag__ x;
}
}
else
__real__ retval = __imag__ retval = __imag__ x - __imag__ x;
}
return retval;
}
weak_alias (s(__cexp), s(cexp))