1#include "libm.h" 2 3#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024 4long double truncl(long double x) { 5 return trunc(x); 6} 7#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384 8 9static const long double toint = 1 / LDBL_EPSILON; 10 11long double truncl(long double x) { 12 union ldshape u = {x}; 13 int e = u.i.se & 0x7fff; 14 int s = u.i.se >> 15; 15 long double y; 16 17 if (e >= 0x3fff + LDBL_MANT_DIG - 1) 18 return x; 19 if (e <= 0x3fff - 1) { 20 FORCE_EVAL(x + 0x1p120f); 21 return x * 0; 22 } 23 /* y = int(|x|) - |x|, where int(|x|) is an integer neighbor of |x| */ 24 if (s) 25 x = -x; 26 y = x + toint - toint - x; 27 if (y > 0) 28 y -= 1; 29 x += y; 30 return s ? -x : x; 31} 32#endif 33