1#include "libm.h"
 2
 3float coshf(float x)
 4{
 5	union {float f; uint32_t i;} u = {.f = x};
 6	uint32_t w;
 7	float t;
 8
 9	/* |x| */
10	u.i &= 0x7fffffff;
11	x = u.f;
12	w = u.i;
13
14	/* |x| < log(2) */
15	if (w < 0x3f317217) {
16		if (w < 0x3f800000 - (12<<23)) {
17			FORCE_EVAL(x + 0x1p120f);
18			return 1;
19		}
20		t = expm1f(x);
21		return 1 + t*t/(2*(1+t));
22	}
23
24	/* |x| < log(FLT_MAX) */
25	if (w < 0x42b17217) {
26		t = expf(x);
27		return 0.5f*(t + 1/t);
28	}
29
30	/* |x| > log(FLT_MAX) or nan */
31#ifdef __wasilibc_unmodified_upstream // Wasm doesn't have alternate rounding modes
32	t = __expo2f(x, 1.0f);
33#else
34	t = __expo2f(x);
35#endif
36	return t;
37}