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
exp10l(long double x)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
exp10l(long double x)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);
33