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#include "libm.h" // for ldshape, ldshape::(anonymous)
#include <float.h> // for LDBL_MANT_DIG, LDBL_MAX_EXP
#include <math.h> // for expm1l, tanhl
#include <stdint.h> // for uint32_t
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
long double tanhl(long double x)
{
return tanh(x);
}
#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
long double tanhl(long double x)
{
union ldshape u = { x };
unsigned ex = u.i.se & 0x7fff;
unsigned sign = u.i.se & 0x8000;
uint32_t w;
long double t;
/* x = |x| */
u.i.se = ex;
x = u.f;
w = u.i.m >> 32;
if (ex > 0x3ffe || (ex == 0x3ffe && w > 0x8c9f53d5)) {
/* |x| > log(3)/2 ~= 0.5493 or nan */
if (ex >= 0x3fff + 5) {
/* |x| >= 32 */
t = 1 + 0 / (x + 0x1p-120f);
} else {
t = expm1l(2 * x);
t = 1 - 2 / (t + 2);
}
} else if (ex > 0x3ffd || (ex == 0x3ffd && w > 0x82c577d4)) {
/* |x| > log(5/3)/2 ~= 0.2554 */
t = expm1l(2 * x);
t = t / (t + 2);
} else {
/* |x| is small */
t = expm1l(-2 * x);
t = -t / (t + 2);
}
return sign ? -t : t;
}
#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
// TODO: broken implementation to make things compile
long double tanhl(long double x)
{
return tanh(x);
}
#endif
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