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path: root/src/math/sincosf.c
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 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 /* origin: FreeBSD /usr/src/lib/msun/src/s_sinf.c */ /* * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. * Optimized by Bruce D. Evans. */ /* * ==================================================== * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. * * Developed at SunPro, a Sun Microsystems, Inc. business. * Permission to use, copy, modify, and distribute this * software is freely granted, provided that this notice * is preserved. * ==================================================== */ #include "libm.h" /* Small multiples of pi/2 rounded to double precision. */ static const double s1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */ s2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */ s3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */ s4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */ void sincosf(float x, float *sin, float *cos) { double y, s, c; uint32_t n, hx, ix; GET_FLOAT_WORD(hx, x); ix = hx & 0x7fffffff; /* |x| ~<= pi/4 */ if (ix <= 0x3f490fda) { /* |x| < 2**-12 */ if (ix < 0x39800000) { /* raise inexact if x != 0 */ if((int)x == 0) { *sin = x; *cos = 1.0f; } return; } *sin = __sindf(x); *cos = __cosdf(x); return; } /* |x| ~<= 5*pi/4 */ if (ix <= 0x407b53d1) { if (ix <= 0x4016cbe3) { /* |x| ~<= 3pi/4 */ if (hx < 0x80000000) { *sin = __cosdf(x - s1pio2); *cos = __sindf(s1pio2 - x); } else { *sin = -__cosdf(x + s1pio2); *cos = __sindf(x + s1pio2); } return; } *sin = __sindf(hx < 0x80000000 ? s2pio2 - x : -s2pio2 - x); *cos = -__cosdf(hx < 0x80000000 ? x - s2pio2 : x + s2pio2); return; } /* |x| ~<= 9*pi/4 */ if (ix <= 0x40e231d5) { if (ix <= 0x40afeddf) { /* |x| ~<= 7*pi/4 */ if (hx < 0x80000000) { *sin = -__cosdf(x - s3pio2); *cos = __sindf(x - s3pio2); } else { *sin = __cosdf(x + s3pio2); *cos = __sindf(-s3pio2 - x); } return; } *sin = __sindf(hx < 0x80000000 ? x - s4pio2 : x + s4pio2); *cos = __cosdf(hx < 0x80000000 ? x - s4pio2 : x + s4pio2); return; } /* sin(Inf or NaN) is NaN */ if (ix >= 0x7f800000) { *sin = *cos = x - x; return; } /* general argument reduction needed */ n = __rem_pio2f(x, &y); s = __sindf(y); c = __cosdf(y); switch (n&3) { case 0: *sin = s; *cos = c; break; case 1: *sin = c; *cos = -s; break; case 2: *sin = -s; *cos = -c; break; case 3: default: *sin = -c; *cos = s; break; } }