1*7db632caSSascha Wildner /*-
2*7db632caSSascha Wildner * ====================================================
3*7db632caSSascha Wildner * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
4*7db632caSSascha Wildner *
5*7db632caSSascha Wildner * Developed at SunPro, a Sun Microsystems, Inc. business.
6*7db632caSSascha Wildner * Permission to use, copy, modify, and distribute this
7*7db632caSSascha Wildner * software is freely granted, provided that this notice
8*7db632caSSascha Wildner * is preserved.
9*7db632caSSascha Wildner * ====================================================
10*7db632caSSascha Wildner */
11*7db632caSSascha Wildner
12*7db632caSSascha Wildner /* s_sincosf.c -- float version of s_sincos.c.
13*7db632caSSascha Wildner * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
14*7db632caSSascha Wildner * Optimized by Bruce D. Evans.
15*7db632caSSascha Wildner * Merged s_sinf.c and s_cosf.c by Steven G. Kargl.
16*7db632caSSascha Wildner */
17*7db632caSSascha Wildner
18*7db632caSSascha Wildner #include <float.h>
19*7db632caSSascha Wildner #include "math.h"
20*7db632caSSascha Wildner
21*7db632caSSascha Wildner #include "math_private.h"
22*7db632caSSascha Wildner #include "k_sincosf.h"
23*7db632caSSascha Wildner
24*7db632caSSascha Wildner /* Small multiples of pi/2 rounded to double precision. */
25*7db632caSSascha Wildner static const double
26*7db632caSSascha Wildner p1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */
27*7db632caSSascha Wildner p2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */
28*7db632caSSascha Wildner p3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */
29*7db632caSSascha Wildner p4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */
30*7db632caSSascha Wildner
31*7db632caSSascha Wildner void
sincosf(float x,float * sn,float * cs)32*7db632caSSascha Wildner sincosf(float x, float *sn, float *cs)
33*7db632caSSascha Wildner {
34*7db632caSSascha Wildner float c, s;
35*7db632caSSascha Wildner float y[2];
36*7db632caSSascha Wildner int32_t n, hx, ix;
37*7db632caSSascha Wildner
38*7db632caSSascha Wildner GET_FLOAT_WORD(hx, x);
39*7db632caSSascha Wildner ix = hx & 0x7fffffff;
40*7db632caSSascha Wildner
41*7db632caSSascha Wildner if (ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
42*7db632caSSascha Wildner if (ix < 0x39800000) { /* |x| < 2**-12 */
43*7db632caSSascha Wildner if ((int)x == 0) {
44*7db632caSSascha Wildner *sn = x; /* x with inexact if x != 0 */
45*7db632caSSascha Wildner *cs = 1;
46*7db632caSSascha Wildner return;
47*7db632caSSascha Wildner }
48*7db632caSSascha Wildner }
49*7db632caSSascha Wildner __kernel_sincosdf(x, sn, cs);
50*7db632caSSascha Wildner return;
51*7db632caSSascha Wildner }
52*7db632caSSascha Wildner
53*7db632caSSascha Wildner if (ix <= 0x407b53d1) { /* |x| ~<= 5*pi/4 */
54*7db632caSSascha Wildner if (ix <= 0x4016cbe3) { /* |x| ~<= 3pi/4 */
55*7db632caSSascha Wildner if (hx > 0) {
56*7db632caSSascha Wildner __kernel_sincosdf(x - p1pio2, cs, sn);
57*7db632caSSascha Wildner *cs = -*cs;
58*7db632caSSascha Wildner } else {
59*7db632caSSascha Wildner __kernel_sincosdf(x + p1pio2, cs, sn);
60*7db632caSSascha Wildner *sn = -*sn;
61*7db632caSSascha Wildner }
62*7db632caSSascha Wildner } else {
63*7db632caSSascha Wildner if (hx > 0)
64*7db632caSSascha Wildner __kernel_sincosdf(x - p2pio2, sn, cs);
65*7db632caSSascha Wildner else
66*7db632caSSascha Wildner __kernel_sincosdf(x + p2pio2, sn, cs);
67*7db632caSSascha Wildner *sn = -*sn;
68*7db632caSSascha Wildner *cs = -*cs;
69*7db632caSSascha Wildner }
70*7db632caSSascha Wildner return;
71*7db632caSSascha Wildner }
72*7db632caSSascha Wildner
73*7db632caSSascha Wildner if (ix <= 0x40e231d5) { /* |x| ~<= 9*pi/4 */
74*7db632caSSascha Wildner if (ix <= 0x40afeddf) { /* |x| ~<= 7*pi/4 */
75*7db632caSSascha Wildner if (hx > 0) {
76*7db632caSSascha Wildner __kernel_sincosdf(x - p3pio2, cs, sn);
77*7db632caSSascha Wildner *sn = -*sn;
78*7db632caSSascha Wildner } else {
79*7db632caSSascha Wildner __kernel_sincosdf(x + p3pio2, cs, sn);
80*7db632caSSascha Wildner *cs = -*cs;
81*7db632caSSascha Wildner }
82*7db632caSSascha Wildner } else {
83*7db632caSSascha Wildner if (hx > 0)
84*7db632caSSascha Wildner __kernel_sincosdf(x - p4pio2, sn, cs);
85*7db632caSSascha Wildner else
86*7db632caSSascha Wildner __kernel_sincosdf(x + p4pio2, sn, cs);
87*7db632caSSascha Wildner }
88*7db632caSSascha Wildner return;
89*7db632caSSascha Wildner }
90*7db632caSSascha Wildner
91*7db632caSSascha Wildner /* If x = Inf or NaN, then sin(x) = NaN and cos(x) = NaN. */
92*7db632caSSascha Wildner if (ix >= 0x7f800000) {
93*7db632caSSascha Wildner *sn = x - x;
94*7db632caSSascha Wildner *cs = x - x;
95*7db632caSSascha Wildner return;
96*7db632caSSascha Wildner }
97*7db632caSSascha Wildner
98*7db632caSSascha Wildner /* Argument reduction. */
99*7db632caSSascha Wildner n = __ieee754_rem_pio2f(x, y);
100*7db632caSSascha Wildner s = __kernel_sinf(y[0], y[1], 1);
101*7db632caSSascha Wildner c = __kernel_cosf(y[0], y[1]);
102*7db632caSSascha Wildner
103*7db632caSSascha Wildner switch(n & 3) {
104*7db632caSSascha Wildner case 0:
105*7db632caSSascha Wildner *sn = s;
106*7db632caSSascha Wildner *cs = c;
107*7db632caSSascha Wildner break;
108*7db632caSSascha Wildner case 1:
109*7db632caSSascha Wildner *sn = c;
110*7db632caSSascha Wildner *cs = -s;
111*7db632caSSascha Wildner break;
112*7db632caSSascha Wildner case 2:
113*7db632caSSascha Wildner *sn = -s;
114*7db632caSSascha Wildner *cs = -c;
115*7db632caSSascha Wildner break;
116*7db632caSSascha Wildner default:
117*7db632caSSascha Wildner *sn = -c;
118*7db632caSSascha Wildner *cs = s;
119*7db632caSSascha Wildner }
120*7db632caSSascha Wildner }
121