src/math/rintl.c

   1 #include "libm.h"
   2
   3 #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
   4 long double rintl(long double x)
   5 {
   6         return rint(x);
   7 }
   8 #elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
   9 #if LDBL_MANT_DIG == 64
  10 #define TOINT 0x1p63
  11 #elif LDBL_MANT_DIG == 113
  12 #define TOINT 0x1p112
  13 #endif
  14 long double rintl(long double x)
  15 {
  16         union ldshape u = {x};
  17         int e = u.i.se & 0x7fff;
  18         int s = u.i.se >> 15;
  19         long double y;
  20
  21         if (e >= 0x3fff+LDBL_MANT_DIG-1)
  22                 return x;
  23         if (s)
  24                 y = x - TOINT + TOINT;
  25         else
  26                 y = x + TOINT - TOINT;
  27         if (y == 0)
  28                 return 0*x;
  29         return y;
  30 }
  31 #endif