1#include "libm.h" 2 3#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 4long double acoshl(long double x) { 5 return acosh(x); 6} 7#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384 8/* acosh(x) = log(x + sqrt(x*x-1)) */ 9long double acoshl(long double x) { 10 union ldshape u = {x}; 11 int e = u.i.se & 0x7fff; 12 13 if (e < 0x3fff + 1) /* |x| < 2, invalid if x < 1 or nan */ 14 return log1pl(x - 1 + sqrtl((x - 1) * (x - 1) + 2 * (x - 1))); 15 if (e < 0x3fff + 32) /* |x| < 0x1p32 */ 16 return logl(2 * x - 1 / (x + sqrtl(x * x - 1))); 17 return logl(x) + 0.693147180559945309417232121458176568L; 18} 19#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384 20// TODO: broken implementation to make things compile 21long double acoshl(long double x) { 22 return acosh(x); 23} 24#endif 25