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#include "libm.h" // for ldshape, ldshape::(anonymous), FORCE_EVAL
#include <float.h> // for LDBL_MANT_DIG, LDBL_MAX_EXP
#include <math.h> // for logl, sqrtl, asinhl, log1pl
#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
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