xref: /dflybsd-src/contrib/openbsd_libm/src/s_sinf.c (revision 4382f29d99a100bd77a81697c2f699c11f6a472a)
1*05a0b428SJohn Marino /* s_sinf.c -- float version of s_sin.c.
2*05a0b428SJohn Marino  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3*05a0b428SJohn Marino  */
4*05a0b428SJohn Marino 
5*05a0b428SJohn Marino /*
6*05a0b428SJohn Marino  * ====================================================
7*05a0b428SJohn Marino  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8*05a0b428SJohn Marino  *
9*05a0b428SJohn Marino  * Developed at SunPro, a Sun Microsystems, Inc. business.
10*05a0b428SJohn Marino  * Permission to use, copy, modify, and distribute this
11*05a0b428SJohn Marino  * software is freely granted, provided that this notice
12*05a0b428SJohn Marino  * is preserved.
13*05a0b428SJohn Marino  * ====================================================
14*05a0b428SJohn Marino  */
15*05a0b428SJohn Marino 
16*05a0b428SJohn Marino #include "math.h"
17*05a0b428SJohn Marino #include "math_private.h"
18*05a0b428SJohn Marino 
19*05a0b428SJohn Marino float
sinf(float x)20*05a0b428SJohn Marino sinf(float x)
21*05a0b428SJohn Marino {
22*05a0b428SJohn Marino 	float y[2],z=0.0;
23*05a0b428SJohn Marino 	int32_t n, ix;
24*05a0b428SJohn Marino 
25*05a0b428SJohn Marino 	GET_FLOAT_WORD(ix,x);
26*05a0b428SJohn Marino 
27*05a0b428SJohn Marino     /* |x| ~< pi/4 */
28*05a0b428SJohn Marino 	ix &= 0x7fffffff;
29*05a0b428SJohn Marino 	if(ix <= 0x3f490fd8) return __kernel_sinf(x,z,0);
30*05a0b428SJohn Marino 
31*05a0b428SJohn Marino     /* sin(Inf or NaN) is NaN */
32*05a0b428SJohn Marino 	else if (ix>=0x7f800000) return x-x;
33*05a0b428SJohn Marino 
34*05a0b428SJohn Marino     /* argument reduction needed */
35*05a0b428SJohn Marino 	else {
36*05a0b428SJohn Marino 	    n = __ieee754_rem_pio2f(x,y);
37*05a0b428SJohn Marino 	    switch(n&3) {
38*05a0b428SJohn Marino 		case 0: return  __kernel_sinf(y[0],y[1],1);
39*05a0b428SJohn Marino 		case 1: return  __kernel_cosf(y[0],y[1]);
40*05a0b428SJohn Marino 		case 2: return -__kernel_sinf(y[0],y[1],1);
41*05a0b428SJohn Marino 		default:
42*05a0b428SJohn Marino 			return -__kernel_cosf(y[0],y[1]);
43*05a0b428SJohn Marino 	    }
44*05a0b428SJohn Marino 	}
45*05a0b428SJohn Marino }
46