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/* k_sinf.c -- float version of k_sin.c |
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* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
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*/ |
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/* |
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* ==================================================== |
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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* |
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* Developed at SunPro, a Sun Microsystems, Inc. business. |
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* Permission to use, copy, modify, and distribute this |
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* software is freely granted, provided that this notice |
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* is preserved. |
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* ==================================================== |
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*/ |
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#include "math.h" |
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#include "math_private.h" |
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static const float |
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half = 5.0000000000e-01,/* 0x3f000000 */ |
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S1 = -1.6666667163e-01, /* 0xbe2aaaab */ |
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S2 = 8.3333337680e-03, /* 0x3c088889 */ |
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S3 = -1.9841270114e-04, /* 0xb9500d01 */ |
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S4 = 2.7557314297e-06, /* 0x3638ef1b */ |
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S5 = -2.5050759689e-08, /* 0xb2d72f34 */ |
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S6 = 1.5896910177e-10; /* 0x2f2ec9d3 */ |
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float |
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__kernel_sinf(float x, float y, int iy) |
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{ |
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float z,r,v; |
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int32_t ix; |
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GET_FLOAT_WORD(ix,x); |
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ix &= 0x7fffffff; /* high word of x */ |
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if(ix<0x32000000) /* |x| < 2**-27 */ |
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{if((int)x==0) return x;} /* generate inexact */ |
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z = x*x; |
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v = z*x; |
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r = S2+z*(S3+z*(S4+z*(S5+z*S6))); |
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if(iy==0) return x+v*(S1+z*r); |
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else return x-((z*(half*y-v*r)-y)-v*S1); |
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} |