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#if !defined(__ppc__)
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#if defined(LIBM_SCCS) && !defined(lint)
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static char rcsid[] =
"$NetBSD: s_rint.c,v 1.8 1995/05/10 20:48:04 jtc Exp $";
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#endif
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#include "math.h"
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#include "mathP.h"
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#ifdef __STDC__
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static const double
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#else
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static double
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#endif
00036 TWO52[2]={
00037 4.50359962737049600000e+15,
00038 -4.50359962737049600000e+15,
00039 };
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#ifdef __STDC__
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double rint(
double x)
00043 #
else
00044 double rint(x)
00045 double x;
00046 #endif
00047 {
00048 int32_t i0,
j0,sx;
00049 u_int32_t i,i1;
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double w,t;
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EXTRACT_WORDS(i0,i1,x);
00052 sx = (i0>>31)&1;
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j0 = ((i0>>20)&0x7ff)-0x3ff;
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if(
j0<20) {
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if(
j0<0) {
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if(((i0&0x7fffffff)|i1)==0)
return x;
00057 i1 |= (i0&0x0fffff);
00058 i0 &= 0xfffe0000;
00059 i0 |= ((i1|-i1)>>12)&0x80000;
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SET_HIGH_WORD(x,i0);
00061 w =
TWO52[sx]+x;
00062 t = w-
TWO52[sx];
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GET_HIGH_WORD(i0,t);
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SET_HIGH_WORD(t,(i0&0x7fffffff)|(sx<<31));
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return t;
00066 }
else {
00067 i = (0x000fffff)>>
j0;
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if(((i0&i)|i1)==0)
return x;
00069 i>>=1;
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if(((i0&i)|i1)!=0) {
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if(
j0==19) i1 = 0x40000000;
else
00072 i0 = (i0&(~i))|((0x20000)>>
j0);
00073 }
00074 }
00075 }
else if (
j0>51) {
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if(
j0==0x400)
return x+x;
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else return x;
00078 }
else {
00079 i = ((u_int32_t)(0xffffffff))>>(
j0-20);
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if((i1&i)==0)
return x;
00081 i>>=1;
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if((i1&i)!=0) i1 = (i1&(~i))|((0x40000000)>>(
j0-20));
00083 }
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INSERT_WORDS(x,i0,i1);
00085 w =
TWO52[sx]+x;
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return w-
TWO52[sx];
00087 }
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#endif