1 #include "libm.h"
2 
3 #if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
tanl(long double x)4 long double tanl(long double x)
5 {
6 	return tan(x);
7 }
8 #elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
tanl(long double x)9 long double tanl(long double x)
10 {
11 	union ldshape u = {x};
12 	long double y[2];
13 	unsigned n;
14 
15 	u.i.se &= 0x7fff;
16 	if (u.i.se == 0x7fff)
17 		return x - x;
18 	if (u.f < M_PI_4) {
19 		if (u.i.se < 0x3fff - LDBL_MANT_DIG/2) {
20 			/* raise inexact if x!=0 and underflow if subnormal */
21 			FORCE_EVAL(u.i.se == 0 ? x*0x1p-120f : x+0x1p120f);
22 			return x;
23 		}
24 		return __tanl(x, 0, 0);
25 	}
26 	n = __rem_pio2l(x, y);
27 	return __tanl(y[0], y[1], n&1);
28 }
29 #endif
30