0,0 → 1,57 |
/* sf_tan.c -- float version of s_tan.c. |
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
*/ |
|
/* |
* ==================================================== |
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
* |
* Developed at SunPro, a Sun Microsystems, Inc. business. |
* Permission to use, copy, modify, and distribute this |
* software is freely granted, provided that this notice |
* is preserved. |
* ==================================================== |
*/ |
|
#include "fdlibm.h" |
|
#ifdef __STDC__ |
float tanf(float x) |
#else |
float tanf(x) |
float x; |
#endif |
{ |
float y[2],z=0.0; |
__int32_t n,ix; |
|
GET_FLOAT_WORD(ix,x); |
|
/* |x| ~< pi/4 */ |
ix &= 0x7fffffff; |
if(ix <= 0x3f490fda) return __kernel_tanf(x,z,1); |
|
/* tan(Inf or NaN) is NaN */ |
else if (!FLT_UWORD_IS_FINITE(ix)) return x-x; /* NaN */ |
|
/* argument reduction needed */ |
else { |
n = __ieee754_rem_pio2f(x,y); |
return __kernel_tanf(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even |
-1 -- n odd */ |
} |
} |
|
#ifdef _DOUBLE_IS_32BITS |
|
#ifdef __STDC__ |
double tan(double x) |
#else |
double tan(x) |
double x; |
#endif |
{ |
return (double) tanf((float) x); |
} |
|
#endif /* defined(_DOUBLE_IS_32BITS) */ |