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
| 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
|
17static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_tanf.c 151969 2005-11-02 14:01:45Z bde $";
| 17static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_tanf.c 152540 2005-11-17 03:53:22Z bde $";
|
18#endif
19
20#include "math.h"
21#include "math_private.h"
22
23float
24tanf(float x)
25{
| 18#endif
19
20#include "math.h"
21#include "math_private.h"
22
23float
24tanf(float x)
25{
|
26 float y[2],z=0.0;
| 26 float y[2];
|
27 int32_t n, ix;
28
29 GET_FLOAT_WORD(ix,x);
| 27 int32_t n, ix;
28
29 GET_FLOAT_WORD(ix,x);
|
30
31 /* |x| ~< pi/4 */
| |
32 ix &= 0x7fffffff;
| 30 ix &= 0x7fffffff;
|
33 if(ix <= 0x3f490fda) {
34 if(ix<0x39800000) /* |x| < 2**-12 */
35 if(((int)x)==0) return x; /* generate inexact */
36 return __kernel_tanf(x,z,1);
| 31
32 if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
33 if(ix<0x39800000) /* |x| < 2**-12 */
34 if(((int)x)==0) return x; /* x with inexact if x != 0 */
35 return __kernel_tanf(x,0.0,1);
|
37 }
38
39 /* tan(Inf or NaN) is NaN */
| 36 }
37
38 /* tan(Inf or NaN) is NaN */
|
40 else if (ix>=0x7f800000) return x-x; /* NaN */
| 39 else if (ix>=0x7f800000) return x-x;
|
41
42 /* argument reduction needed */
43 else {
44 n = __ieee754_rem_pio2f(x,y);
| 40
41 /* argument reduction needed */
42 else {
43 n = __ieee754_rem_pio2f(x,y);
|
45 return __kernel_tanf(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even
46 -1 -- n odd */
| 44 /* integer parameter: 1 -- n even; -1 -- n odd */
45 return __kernel_tanf(y[0],y[1],1-((n&1)<<1));
|
47 }
48}
| 46 }
47}
|