1#define _GNU_SOURCE
2#include <math.h>
3#include <stdint.h>
4#include "libm.h"
5
6float exp10f(float x)
7{
8	static const float p10[] = {
9		1e-7f, 1e-6f, 1e-5f, 1e-4f, 1e-3f, 1e-2f, 1e-1f,
10		1, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7
11	};
12	float n, y = modff(x, &n);
13	union {float f; uint32_t i;} u = {n};
14	/* fabsf(n) < 8 without raising invalid on nan */
15	if ((u.i>>23 & 0xff) < 0x7f+3) {
16		if (!y) return p10[(int)n+7];
17		y = exp2f(3.32192809488736234787031942948939f * y);
18		return y * p10[(int)n+7];
19	}
20	return exp2(3.32192809488736234787031942948939 * x);
21}
22
23weak_alias(exp10f, pow10f);
24