third_party/ulib/musl/src/math/asinhl.c

#include "libm.h"

#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
long double asinhl(long double x) {
    return asinh(x);
}
#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
/* asinh(x) = sign(x)*log(|x|+sqrt(x*x+1)) ~= x - x^3/6 + o(x^5) */
long double asinhl(long double x) {
    union ldshape u = {x};
    unsigned e = u.i.se & 0x7fff;
    unsigned s = u.i.se >> 15;

    /* |x| */
    u.i.se = e;
    x = u.f;

    if (e >= 0x3fff + 32) {
        /* |x| >= 0x1p32 or inf or nan */
        x = logl(x) + 0.693147180559945309417232121458176568L;
    } else if (e >= 0x3fff + 1) {
        /* |x| >= 2 */
        x = logl(2 * x + 1 / (sqrtl(x * x + 1) + x));
    } else if (e >= 0x3fff - 32) {
        /* |x| >= 0x1p-32 */
        x = log1pl(x + x * x / (sqrtl(x * x + 1) + 1));
    } else {
        /* |x| < 0x1p-32, raise inexact if x!=0 */
        FORCE_EVAL(x + 0x1p120f);
    }
    return s ? -x : x;
}
#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
// TODO: broken implementation to make things compile
long double asinhl(long double x) {
    return asinh(x);
}
#endif