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Viewing changes to lib9/fmt/nan64.c

  • Committer: Bazaar Package Importer
  • Author(s): Daniel Baumann
  • Date: 2009-08-20 17:34:06 UTC
  • mfrom: (6.2.2 squeeze)
  • Revision ID: james.westby@ubuntu.com-20090820173406-xpwqa9ruyevvc0ut
Tags: 1:3-3
* Updating maintainer field.
* Updating vcs fields.
* Updating package to standards version 3.8.3.
* Updatin variables writing in rules to consistent style.

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lib9/fmt/nan64.c
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 */
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#include "plan9.h"
 
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#include <assert.h>
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#include "fmt.h"
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#include "fmtdef.h"
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#if defined (__APPLE__) || (__powerpc__)
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#define _NEEDLL
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#endif
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static uvlong uvnan    = ((uvlong)0x7FF00000<<32)|0x00000001;
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static uvlong uvinf    = ((uvlong)0x7FF00000<<32)|0x00000000;
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static uvlong uvneginf = ((uvlong)0xFFF00000<<32)|0x00000000;
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/* gcc sees through the obvious casts. */
 
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static uvlong
 
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d2u(double d)
 
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{
 
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        union {
 
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                uvlong v;
 
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                double d;
 
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        } u;
 
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        assert(sizeof(u.d) == sizeof(u.v));
 
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        u.d = d;
 
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        return u.v;
 
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}
 
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static double
 
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u2d(uvlong v)
 
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{
 
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        union {
 
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                uvlong v;
 
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                double d;
 
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        } u;
 
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        assert(sizeof(u.d) == sizeof(u.v));
 
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        u.v = v;
 
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        return u.d;
 
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}
 
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double
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__NaN(void)
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{
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        uvlong *p;
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        /* gcc complains about "return *(double*)&uvnan;" */
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        p = &uvnan;
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        return *(double*)p;
 
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        return u2d(uvnan);
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}
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int
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__isNaN(double d)
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{
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        uvlong x;
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        double *p;
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        p = &d;
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        x = *(uvlong*)p;
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        return (ulong)(x>>32)==0x7FF00000 && !__isInf(d, 0);
 
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        x = d2u(d);
 
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        /* IEEE 754: exponent bits 0x7FF and non-zero mantissa */
 
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        return (x&uvinf) == uvinf && (x&~uvneginf) != 0;
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}
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double
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__Inf(int sign)
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{
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        uvlong *p;
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        if(sign < 0)
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                p = &uvinf;
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        else
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                p = &uvneginf;
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        return *(double*)p;
 
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        return u2d(sign < 0 ? uvneginf : uvinf);
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}
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int
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__isInf(double d, int sign)
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{
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        uvlong x;
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        double *p;
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        p = &d;
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        x = *(uvlong*)p;
 
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        x = d2u(d);
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        if(sign == 0)
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                return x==uvinf || x==uvneginf;
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        else if(sign > 0)