1/* k_tanf.c -- float version of k_tan.c
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4
5/*
6 * ====================================================
7 * Copyright 2004 Sun Microsystems, Inc. All Rights Reserved.
8 *
9 * Permission to use, copy, modify, and distribute this
10 * software is freely granted, provided that this notice
11 * is preserved.
12 * ====================================================
13 */
14
15#ifndef lint
| 1/* k_tanf.c -- float version of k_tan.c
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4
5/*
6 * ====================================================
7 * Copyright 2004 Sun Microsystems, Inc. All Rights Reserved.
8 *
9 * Permission to use, copy, modify, and distribute this
10 * software is freely granted, provided that this notice
11 * is preserved.
12 * ====================================================
13 */
14
15#ifndef lint
|
16static char rcsid[] = "$FreeBSD: head/lib/msun/src/k_tanf.c 152284 2005-11-10 17:43:49Z bde $";
| 16static char rcsid[] = "$FreeBSD: head/lib/msun/src/k_tanf.c 152343 2005-11-12 20:06:04Z bde $";
|
17#endif
18
19#include "math.h"
20#include "math_private.h"
| 17#endif
18
19#include "math.h"
20#include "math_private.h"
|
| 21
|
21static const float
| 22static const float
|
22one = 1.0000000000e+00, /* 0x3f800000 */
| |
23pio4 = 7.8539812565e-01, /* 0x3f490fda */
24pio4lo= 3.7748947079e-08, /* 0x33222168 */
| 23pio4 = 7.8539812565e-01, /* 0x3f490fda */
24pio4lo= 3.7748947079e-08, /* 0x33222168 */
|
25/* Bounds for tan(x)/x - t(x): ~[-1.73e-09, 1.724e-09]. */
| 25/* |tan(x)/x - t(x)| < 2**-29.2 (~[-1.73e-09, 1.724e-09]). */
|
26T[] = {
| 26T[] = {
|
27 0xaaaaa3.0p-25, /* 0.33333310485 */
28 0x888b06.0p-26, /* 0.13334283238 */
29 0xdc84c8.0p-28, /* 0.053837567568 */
30 0xb9d8f1.0p-29, /* 0.022686453536 */
31 0xcfe632.0p-31, /* 0.0063445800915 */
32 0xeaf97e.0p-31, /* 0.0071708550677 */
| 27 0xaaaaa3.0p-25, /* 0.33333310485 */
28 0x888b06.0p-26, /* 0.13334283238 */
29 0xdc84c8.0p-28, /* 0.053837567568 */
30 0xb9d8f1.0p-29, /* 0.022686453536 */
31 0xcfe632.0p-31, /* 0.0063445800915 */
32 0xeaf97e.0p-31, /* 0.0071708550677 */
|
33};
34
35float
36__kernel_tanf(float x, float y, int iy)
37{
38 float z,r,v,w,s;
39 int32_t ix,hx;
| 33};
34
35float
36__kernel_tanf(float x, float y, int iy)
37{
38 float z,r,v,w,s;
39 int32_t ix,hx;
|
| 40
|
40 GET_FLOAT_WORD(hx,x);
| 41 GET_FLOAT_WORD(hx,x);
|
41 ix = hx&0x7fffffff; /* high word of |x| */
42 if(ix>=0x3f2ca140) { /* |x|>=0.6744 */
| 42 ix = hx&0x7fffffff;
43 if(ix>=0x3f2ca140) { /* |x|>=0.67434 */
|
43 if(hx<0) {x = -x; y = -y;}
44 z = pio4-x;
45 w = pio4lo-y;
46 x = z+w; y = 0.0;
47 }
48 z = x*x;
49 w = z*z;
50 /* Break x^5*(T[1]+x^2*T[2]+...) into
--- 30 unchanged lines hidden --- | 44 if(hx<0) {x = -x; y = -y;}
45 z = pio4-x;
46 w = pio4lo-y;
47 x = z+w; y = 0.0;
48 }
49 z = x*x;
50 w = z*z;
51 /* Break x^5*(T[1]+x^2*T[2]+...) into
--- 30 unchanged lines hidden --- |