/* origin: FreeBSD /usr/src/lib/msun/src/s_ccoshf.c */
/*-
* Copyright (c) 2005 Bruce D. Evans and Steven G. Kargl
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Hyperbolic cosine of a complex argument. See s_ccosh.c for details.
*/
#include "libm.h"
static const float huge = 0x1p127;
float complex ccoshf(float complex z)
{
float x, y, h;
int32_t hx, hy, ix, iy;
x = crealf(z);
y = cimagf(z);
GET_FLOAT_WORD(hx, x);
GET_FLOAT_WORD(hy, y);
ix = 0x7fffffff & hx;
iy = 0x7fffffff & hy;
if (ix < 0x7f800000 && iy < 0x7f800000) {
if (iy == 0)
return cpackf(coshf(x), x * y);
if (ix < 0x41100000) /* small x: normal case */
return cpackf(coshf(x) * cosf(y), sinhf(x) * sinf(y));
/* |x| >= 9, so cosh(x) ~= exp(|x|) */
if (ix < 0x42b17218) {
/* x < 88.7: expf(|x|) won't overflow */
h = expf(fabsf(x)) * 0.5f;
return cpackf(h * cosf(y), copysignf(h, x) * sinf(y));
} else if (ix < 0x4340b1e7) {
/* x < 192.7: scale to avoid overflow */
z = __ldexp_cexpf(cpackf(fabsf(x), y), -1);
return cpackf(crealf(z), cimagf(z) * copysignf(1, x));
} else {
/* x >= 192.7: the result always overflows */
h = huge * x;
return cpackf(h * h * cosf(y), h * sinf(y));
}
}
if (ix == 0 && iy >= 0x7f800000)
return cpackf(y - y, copysignf(0, x * (y - y)));
if (iy == 0 && ix >= 0x7f800000) {
if ((hx & 0x7fffff) == 0)
return cpackf(x * x, copysignf(0, x) * y);
return cpackf(x * x, copysignf(0, (x + x) * y));
}
if (ix < 0x7f800000 && iy >= 0x7f800000)
return cpackf(y - y, x * (y - y));
if (ix >= 0x7f800000 && (hx & 0x7fffff) == 0) {
if (iy >= 0x7f800000)
return cpackf(x * x, x * (y - y));
return cpackf((x * x) * cosf(y), x * sinf(y));
}
return cpackf((x * x) * (y - y), (x + x) * (y - y));
}
