lib/libm/sinhf.c


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#include "libm.h"

float sinhf(float x)
{
	union {
		float f;
		uint32_t i;
	} u = { .f = x };
	uint32_t w;
	float t, h, absx;

	h = 0.5;
	if (u.i >> 31)
		h = -h;
	/* |x| */
	u.i &= 0x7fffffff;
	absx = u.f;
	w = u.i;

	/* |x| < log(FLT_MAX) */
	if (w < 0x42b17217) {
		t = expm1f(absx);
		if (w < 0x3f800000) {
			if (w < 0x3f800000 - (12 << 23))
				return x;
			return h * (2 * t - t * t / (t + 1));
		}
		return h * (t + t / (t + 1));
	}

	/* |x| > logf(FLT_MAX) or nan */
	t = __expo2f(absx, 2 * h);
	return t;
}