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      1 /*-
      2  * ====================================================
      3  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
      4  *
      5  * Developed at SunPro, a Sun Microsystems, Inc. business.
      6  * Permission to use, copy, modify, and distribute this
      7  * software is freely granted, provided that this notice
      8  * is preserved.
      9  * ====================================================
     10  */
     11 
     12 /* s_sincosf.c -- float version of s_sincos.c.
     13  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian (at) cygnus.com.
     14  * Optimized by Bruce D. Evans.
     15  * Merged s_sinf.c and s_cosf.c by Steven G. Kargl.
     16  */
     17 
     18 #include <sys/cdefs.h>
     19 __FBSDID("$FreeBSD: head/lib/msun/src/s_sincosf.c 319047 2017-05-28 06:13:38Z mmel $");
     20 
     21 #include <float.h>
     22 
     23 #include "math.h"
     24 #define INLINE_REM_PIO2F
     25 #include "math_private.h"
     26 #include "e_rem_pio2f.c"
     27 #include "k_sincosf.h"
     28 
     29 /* Small multiples of pi/2 rounded to double precision. */
     30 static const double
     31 p1pio2 = 1*M_PI_2,			/* 0x3FF921FB, 0x54442D18 */
     32 p2pio2 = 2*M_PI_2,			/* 0x400921FB, 0x54442D18 */
     33 p3pio2 = 3*M_PI_2,			/* 0x4012D97C, 0x7F3321D2 */
     34 p4pio2 = 4*M_PI_2;			/* 0x401921FB, 0x54442D18 */
     35 
     36 void
     37 sincosf(float x, float *sn, float *cs)
     38 {
     39 	float c, s;
     40 	double y;
     41 	int32_t n, hx, ix;
     42 
     43 	GET_FLOAT_WORD(hx, x);
     44 	ix = hx & 0x7fffffff;
     45 
     46 	if (ix <= 0x3f490fda) {		/* |x| ~<= pi/4 */
     47 		if (ix < 0x39800000) {	/* |x| < 2**-12 */
     48 			if ((int)x == 0) {
     49 				*sn = x;	/* x with inexact if x != 0 */
     50 				*cs = 1;
     51 				return;
     52 			}
     53 		}
     54 		__kernel_sincosdf(x, sn, cs);
     55 		return;
     56 	}
     57 
     58 	if (ix <= 0x407b53d1) {		/* |x| ~<= 5*pi/4 */
     59 		if (ix <= 0x4016cbe3) {	/* |x| ~<= 3pi/4 */
     60 			if (hx > 0) {
     61 				__kernel_sincosdf(x - p1pio2, cs, sn);
     62 				*cs = -*cs;
     63 			} else {
     64 				__kernel_sincosdf(x + p1pio2, cs, sn);
     65 				*sn = -*sn;
     66 			}
     67 		} else {
     68 			if (hx > 0)
     69 				__kernel_sincosdf(x - p2pio2, sn, cs);
     70 			else
     71 				__kernel_sincosdf(x + p2pio2, sn, cs);
     72 			*sn = -*sn;
     73 			*cs = -*cs;
     74 		}
     75 		return;
     76 	}
     77 
     78 	if (ix <= 0x40e231d5) {		/* |x| ~<= 9*pi/4 */
     79 		if (ix <= 0x40afeddf) {	/* |x| ~<= 7*pi/4 */
     80 			if (hx > 0) {
     81 				__kernel_sincosdf(x - p3pio2, cs, sn);
     82 				*sn = -*sn;
     83 			} else {
     84 				__kernel_sincosdf(x + p3pio2, cs, sn);
     85 				*cs = -*cs;
     86 			}
     87 		} else {
     88 			if (hx > 0)
     89 				__kernel_sincosdf(x - p4pio2, sn, cs);
     90 			else
     91 				__kernel_sincosdf(x + p4pio2, sn, cs);
     92 		}
     93 		return;
     94 	}
     95 
     96 	/* If x = Inf or NaN, then sin(x) = NaN and cos(x) = NaN. */
     97 	if (ix >= 0x7f800000) {
     98 		*sn = x - x;
     99 		*cs = x - x;
    100 		return;
    101 	}
    102 
    103 	/* Argument reduction. */
    104 	n = __ieee754_rem_pio2f(x, &y);
    105 	__kernel_sincosdf(y, &s, &c);
    106 
    107 	switch(n & 3) {
    108 	case 0:
    109 		*sn = s;
    110 		*cs = c;
    111 		break;
    112 	case 1:
    113 		*sn = c;
    114 		*cs = -s;
    115 		break;
    116 	case 2:
    117 		*sn = -s;
    118 		*cs = -c;
    119 		break;
    120 	default:
    121 		*sn = -c;
    122 		*cs = s;
    123 	}
    124 }
    125 
    126 
    127