cosmopolitan/libc/math/tanl.c

30 lines
644 B
C

#include "libc/math/libm.h"
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
long double tanl(long double x)
{
return tan(x);
}
#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
long double tanl(long double x)
{
union ldshape u = {x};
long double y[2];
unsigned n;
u.i.se &= 0x7fff;
if (u.i.se == 0x7fff)
return x - x;
if (u.f < M_PI_4) {
if (u.i.se < 0x3fff - LDBL_MANT_DIG/2) {
/* raise inexact if x!=0 and underflow if subnormal */
FORCE_EVAL(u.i.se == 0 ? x*0x1p-120f : x+0x1p120f);
return x;
}
return __tanl(x, 0, 0);
}
n = __rem_pio2l(x, y);
return __tanl(y[0], y[1], n&1);
}
#endif