vx32

Local 9vx git repository for patches.
git clone git://r-36.net/vx32
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s_tanf.c (1107B)


      1 /* s_tanf.c -- float version of s_tan.c.
      2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
      3  */
      4 
      5 /*
      6  * ====================================================
      7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
      8  *
      9  * Developed at SunPro, a Sun Microsystems, Inc. business.
     10  * Permission to use, copy, modify, and distribute this
     11  * software is freely granted, provided that this notice
     12  * is preserved.
     13  * ====================================================
     14  */
     15 
     16 #ifndef lint
     17 static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_tanf.c,v 1.7 2002/05/28 18:15:04 alfred Exp $";
     18 #endif
     19 
     20 #include "math.h"
     21 #include "math_private.h"
     22 
     23 float
     24 tanf(float x)
     25 {
     26 	float y[2],z=0.0;
     27 	int32_t n, ix;
     28 
     29 	GET_FLOAT_WORD(ix,x);
     30 
     31     /* |x| ~< pi/4 */
     32 	ix &= 0x7fffffff;
     33 	if(ix <= 0x3f490fda) return __kernel_tanf(x,z,1);
     34 
     35     /* tan(Inf or NaN) is NaN */
     36 	else if (ix>=0x7f800000) return x-x;		/* NaN */
     37 
     38     /* argument reduction needed */
     39 	else {
     40 	    n = __ieee754_rem_pio2f(x,y);
     41 	    return __kernel_tanf(y[0],y[1],1-((n&1)<<1)); /*   1 -- n even
     42 							      -1 -- n odd */
     43 	}
     44 }