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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 2 | pj | 1 | /* k_cosf.c -- float version of k_cos.c |
| 2 | * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
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| 3 | */ |
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| 4 | |||
| 5 | /* |
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| 6 | * ==================================================== |
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| 7 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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| 8 | * |
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| 9 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
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| 10 | * Permission to use, copy, modify, and distribute this |
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| 11 | * software is freely granted, provided that this notice |
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| 12 | * is preserved. |
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| 13 | * ==================================================== |
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| 14 | */ |
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| 15 | |||
| 16 | #ifndef lint |
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| 17 | static char rcsid[] = "$\Id: k_cosf.c,v 1.2 1995/05/30 05:48:55 rgrimes Exp $"; |
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| 18 | #endif |
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| 19 | |||
| 20 | #include "math.h" |
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| 21 | #include "math_private.h" |
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| 22 | |||
| 23 | #ifdef __STDC__ |
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| 24 | static const float |
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| 25 | #else |
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| 26 | static float |
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| 27 | #endif |
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| 28 | one = 1.0000000000e+00, /* 0x3f800000 */ |
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| 29 | C1 = 4.1666667908e-02, /* 0x3d2aaaab */ |
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| 30 | C2 = -1.3888889225e-03, /* 0xbab60b61 */ |
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| 31 | C3 = 2.4801587642e-05, /* 0x37d00d01 */ |
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| 32 | C4 = -2.7557314297e-07, /* 0xb493f27c */ |
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| 33 | C5 = 2.0875723372e-09, /* 0x310f74f6 */ |
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| 34 | C6 = -1.1359647598e-11; /* 0xad47d74e */ |
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| 35 | |||
| 36 | #ifdef __STDC__ |
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| 37 | float __kernel_cosf(float x, float y) |
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| 38 | #else |
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| 39 | float __kernel_cosf(x, y) |
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| 40 | float x,y; |
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| 41 | #endif |
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| 42 | { |
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| 43 | float a,hz,z,r,qx; |
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| 44 | int32_t ix; |
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| 45 | GET_FLOAT_WORD(ix,x); |
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| 46 | ix &= 0x7fffffff; /* ix = |x|'s high word*/ |
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| 47 | if(ix<0x32000000) { /* if x < 2**27 */ |
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| 48 | if(((int)x)==0) return one; /* generate inexact */ |
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| 49 | } |
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| 50 | z = x*x; |
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| 51 | r = z*(C1+z*(C2+z*(C3+z*(C4+z*(C5+z*C6))))); |
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| 52 | if(ix < 0x3e99999a) /* if |x| < 0.3 */ |
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| 53 | return one - ((float)0.5*z - (z*r - x*y)); |
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| 54 | else { |
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| 55 | if(ix > 0x3f480000) { /* x > 0.78125 */ |
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| 56 | qx = (float)0.28125; |
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| 57 | } else { |
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| 58 | SET_FLOAT_WORD(qx,ix-0x01000000); /* x/4 */ |
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| 59 | } |
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| 60 | hz = (float)0.5*z-qx; |
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| 61 | a = one-qx; |
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| 62 | return a - (hz - (z*r-x*y)); |
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| 63 | } |
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| 64 | } |