src/math/exp10l.c

   1 #define _GNU_SOURCE
   2 #include <float.h>
   3 #include <math.h>
   4 #include "libm.h"
   5
   6 #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
   7 long double exp10l(long double x)
   8 {
   9         return exp10(x);
  10 }
  11 #elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
  12 long double exp10l(long double x)
  13 {
  14         static const long double p10[] = {
  15                 1e-15L, 1e-14L, 1e-13L, 1e-12L, 1e-11L, 1e-10L,
  16                 1e-9L, 1e-8L, 1e-7L, 1e-6L, 1e-5L, 1e-4L, 1e-3L, 1e-2L, 1e-1L,
  17                 1, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
  18                 1e10, 1e11, 1e12, 1e13, 1e14, 1e15
  19         };
  20         long double n, y = modfl(x, &n);
  21         union ldshape u = {n};
  22         /* fabsl(n) < 16 without raising invalid on nan */
  23         if ((u.i.se & 0x7fff) < 0x3fff+4) {
  24                 if (!y) return p10[(int)n+15];
  25                 y = exp2l(3.32192809488736234787031942948939L * y);
  26                 return y * p10[(int)n+15];
  27         }
  28         return powl(10.0, x);
  29 }
  30 #endif
  31
  32 weak_alias(exp10l, pow10l);