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| Rev | Author | Line No. | Line |
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| 3362 | Serge | 1 | |
| 2 | /* |
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| 3 | * ==================================================== |
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| 4 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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| 5 | * |
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| 6 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
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| 7 | * Permission to use, copy, modify, and distribute this |
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| 8 | * software is freely granted, provided that this notice |
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| 9 | * is preserved. |
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| 10 | * ==================================================== |
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| 11 | */ |
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| 12 | |||
| 13 | |||
| 14 | * Return : |
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| 15 | * returns x REM p = x - [x/p]*p as if in infinite |
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| 16 | * precise arithmetic, where [x/p] is the (infinite bit) |
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| 17 | * integer nearest x/p (in half way case choose the even one). |
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| 18 | * Method : |
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| 19 | * Based on fmod() return x-[x/p]chopped*p exactlp. |
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| 20 | */ |
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| 21 | |||
| 22 | |||
| 23 | |||
| 24 | |||
| 25 | |||
| 26 | |||
| 27 | static const double zero = 0.0; |
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| 28 | #else |
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| 29 | static double zero = 0.0; |
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| 30 | #endif |
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| 31 | |||
| 32 | |||
| 33 | |||
| 34 | double __ieee754_remainder(double x, double p) |
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| 35 | #else |
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| 36 | double __ieee754_remainder(x,p) |
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| 37 | double x,p; |
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| 38 | #endif |
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| 39 | { |
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| 40 | __int32_t hx,hp; |
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| 41 | __uint32_t sx,lx,lp; |
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| 42 | double p_half; |
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| 43 | |||
| 44 | |||
| 45 | EXTRACT_WORDS(hp,lp,p); |
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| 46 | sx = hx&0x80000000; |
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| 47 | hp &= 0x7fffffff; |
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| 48 | hx &= 0x7fffffff; |
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| 49 | |||
| 50 | |||
| 51 | if((hp|lp)==0) return (x*p)/(x*p); /* p = 0 */ |
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| 52 | if((hx>=0x7ff00000)|| /* x not finite */ |
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| 53 | ((hp>=0x7ff00000)&& /* p is NaN */ |
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| 54 | (((hp-0x7ff00000)|lp)!=0))) |
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| 55 | return (x*p)/(x*p); |
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| 56 | |||
| 57 | |||
| 58 | |||
| 59 | if (((hx-hp)|(lx-lp))==0) return zero*x; |
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| 60 | x = fabs(x); |
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| 61 | p = fabs(p); |
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| 62 | if (hp<0x00200000) { |
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| 63 | if(x+x>p) { |
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| 64 | x-=p; |
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| 65 | if(x+x>=p) x -= p; |
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| 66 | } |
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| 67 | } else { |
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| 68 | p_half = 0.5*p; |
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| 69 | if(x>p_half) { |
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| 70 | x-=p; |
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| 71 | if(x>=p_half) x -= p; |
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| 72 | } |
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| 73 | } |
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| 74 | GET_HIGH_WORD(hx,x); |
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| 75 | SET_HIGH_WORD(x,hx^sx); |
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| 76 | return x; |
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| 77 | } |
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| 78 | |||
| 79 | |||
| 80 |