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