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#define _GNU_SOURCE
#include <math.h>
#include <stdint.h>
float exp10f(float x)
{
static const float p10[] = {
1e-7f, 1e-6f, 1e-5f, 1e-4f, 1e-3f, 1e-2f, 1e-1f,
1, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7
};
float n, y = modff(x, &n);
union {float f; uint32_t i;} u = {n};
/* fabsf(n) < 8 without raising invalid on nan */
if ((u.i>>23 & 0xff) < 0x7f+3) {
if (!y) return p10[(int)n+7];
y = exp2f(3.32192809488736234787031942948939f * y);
return y * p10[(int)n+7];
}
return exp2(3.32192809488736234787031942948939 * x);
}
weak_alias(exp10f, pow10f);
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