1/* s_cosf.c -- float version of s_cos.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_cosf.c -- float version of s_cos.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_cosf.c 152540 2005-11-17 03:53:22Z bde $";
| 17static char rcsid[] = "$FreeBSD: head/lib/msun/src/s_cosf.c 152596 2005-11-19 02:38:27Z bde $";
|
18#endif
19
20#include "math.h"
21#include "math_private.h"
22
| 18#endif
19
20#include "math.h"
21#include "math_private.h"
22
|
| 23/* Small multiples of pi/2 rounded to double precision. */
24static const double
25c1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */
26c2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */
27c3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */
28c4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */
29
30static inline float
31__kernel_cosdf(double x)
32{
33 return __kernel_cosf((float)x, x - (float)x);
34}
35
36static inline float
37__kernel_sindf(double x)
38{
39 return __kernel_sinf((float)x, x - (float)x, 1);
40}
41
|
23float
24cosf(float x)
25{
26 float y[2];
27 int32_t n,ix;
28
| 42float
43cosf(float x)
44{
45 float y[2];
46 int32_t n,ix;
47
|
| 48 x = fabsf(x);
|
29 GET_FLOAT_WORD(ix,x);
| 49 GET_FLOAT_WORD(ix,x);
|
30 ix &= 0x7fffffff;
| |
31
32 if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
33 if(ix<0x39800000) /* |x| < 2**-12 */
34 if(((int)x)==0) return 1.0; /* 1 with inexact if x != 0 */
35 return __kernel_cosf(x,0.0);
36 }
| 50
51 if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
52 if(ix<0x39800000) /* |x| < 2**-12 */
53 if(((int)x)==0) return 1.0; /* 1 with inexact if x != 0 */
54 return __kernel_cosf(x,0.0);
55 }
|
| 56 if(ix<=0x407b53d1) { /* |x| <= ~5*pi/4 */
57 if(ix<=0x4016cbe3) /* |x| <= ~3pi/4 */
58 return -__kernel_sindf(x - c1pio2);
59 else
60 return -__kernel_cosdf(x - c2pio2);
61 }
62 if(ix<=0x40e231d5) { /* |x| <= ~9*pi/4 */
63 if(ix<=0x40afeddf) /* |x| <= ~7*pi/4 */
64 return __kernel_sindf(x - c3pio2);
65 else
66 return __kernel_cosdf(x - c4pio2);
67 }
|
37
38 /* cos(Inf or NaN) is NaN */
39 else if (ix>=0x7f800000) return x-x;
40
| 68
69 /* cos(Inf or NaN) is NaN */
70 else if (ix>=0x7f800000) return x-x;
71
|
41 /* argument reduction needed */
| 72 /* general argument reduction needed */
|
42 else {
43 n = __ieee754_rem_pio2f(x,y);
44 switch(n&3) {
45 case 0: return __kernel_cosf(y[0],y[1]);
46 case 1: return -__kernel_sinf(y[0],y[1],1);
47 case 2: return -__kernel_cosf(y[0],y[1]);
48 default:
49 return __kernel_sinf(y[0],y[1],1);
50 }
51 }
52}
| 73 else {
74 n = __ieee754_rem_pio2f(x,y);
75 switch(n&3) {
76 case 0: return __kernel_cosf(y[0],y[1]);
77 case 1: return -__kernel_sinf(y[0],y[1],1);
78 case 2: return -__kernel_cosf(y[0],y[1]);
79 default:
80 return __kernel_sinf(y[0],y[1],1);
81 }
82 }
83}
|