| #include "libm.h" |
| |
| #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 |
| long double acoshl(long double x) { |
| return acosh(x); |
| } |
| #elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 |
| /* acosh(x) = log(x + sqrt(x*x-1)) */ |
| long double acoshl(long double x) { |
| union ldshape u = {x}; |
| int e = u.i.se & 0x7fff; |
| |
| if (e < 0x3fff + 1) /* |x| < 2, invalid if x < 1 or nan */ |
| return log1pl(x - 1 + sqrtl((x - 1) * (x - 1) + 2 * (x - 1))); |
| if (e < 0x3fff + 32) /* |x| < 0x1p32 */ |
| return logl(2 * x - 1 / (x + sqrtl(x * x - 1))); |
| return logl(x) + 0.693147180559945309417232121458176568L; |
| } |
| #elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384 |
| // TODO: broken implementation to make things compile |
| long double acoshl(long double x) { |
| return acosh(x); |
| } |
| #endif |
