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@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 <float.h> 19 20 #include "math.h" 21 #define INLINE_REM_PIO2F 22 #include "math_private.h" 23 #include "e_rem_pio2f.c" 24 #include "k_sincosf.h" 25 26 /* Small multiples of pi/2 rounded to double precision. */ 27 static const double 28 p1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */ 29 p2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */ 30 p3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */ 31 p4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ 32 33 void 34 sincosf(float x, float *sn, float *cs) 35 { 36 float c, s; 37 double y; 38 int32_t n, hx, ix; 39 40 GET_FLOAT_WORD(hx, x); 41 ix = hx & 0x7fffffff; 42 43 if (ix <= 0x3f490fda) { /* |x| ~<= pi/4 */ 44 if (ix < 0x39800000) { /* |x| < 2**-12 */ 45 if ((int)x == 0) { 46 *sn = x; /* x with inexact if x != 0 */ 47 *cs = 1; 48 return; 49 } 50 } 51 __kernel_sincosdf(x, sn, cs); 52 return; 53 } 54 55 if (ix <= 0x407b53d1) { /* |x| ~<= 5*pi/4 */ 56 if (ix <= 0x4016cbe3) { /* |x| ~<= 3pi/4 */ 57 if (hx > 0) { 58 __kernel_sincosdf(x - p1pio2, cs, sn); 59 *cs = -*cs; 60 } else { 61 __kernel_sincosdf(x + p1pio2, cs, sn); 62 *sn = -*sn; 63 } 64 } else { 65 if (hx > 0) 66 __kernel_sincosdf(x - p2pio2, sn, cs); 67 else 68 __kernel_sincosdf(x + p2pio2, sn, cs); 69 *sn = -*sn; 70 *cs = -*cs; 71 } 72 return; 73 } 74 75 if (ix <= 0x40e231d5) { /* |x| ~<= 9*pi/4 */ 76 if (ix <= 0x40afeddf) { /* |x| ~<= 7*pi/4 */ 77 if (hx > 0) { 78 __kernel_sincosdf(x - p3pio2, cs, sn); 79 *sn = -*sn; 80 } else { 81 __kernel_sincosdf(x + p3pio2, cs, sn); 82 *cs = -*cs; 83 } 84 } else { 85 if (hx > 0) 86 __kernel_sincosdf(x - p4pio2, sn, cs); 87 else 88 __kernel_sincosdf(x + p4pio2, sn, cs); 89 } 90 return; 91 } 92 93 /* If x = Inf or NaN, then sin(x) = NaN and cos(x) = NaN. */ 94 if (ix >= 0x7f800000) { 95 *sn = x - x; 96 *cs = x - x; 97 return; 98 } 99 100 /* Argument reduction. */ 101 n = __ieee754_rem_pio2f(x, &y); 102 __kernel_sincosdf(y, &s, &c); 103 104 switch(n & 3) { 105 case 0: 106 *sn = s; 107 *cs = c; 108 break; 109 case 1: 110 *sn = c; 111 *cs = -s; 112 break; 113 case 2: 114 *sn = -s; 115 *cs = -c; 116 break; 117 default: 118 *sn = -c; 119 *cs = s; 120 } 121 } 122 123 124