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#define IBMPC 1
#define DENORMAL 1
#ifdef IBMPC
#define EXPMSK 0x800f
#define MEXP 0x7ff
#define NBITS 64
#endif
#ifdef MIEEE
#define EXPMSK 0x800f
#define MEXP 0x7ff
#define NBITS 64
#endif
extern double MAXNUML;
long double frexpl( x, pw2 )
long double x;
int *pw2;
{
union
{
long double y;
unsigned short sh[6];
} u;
int i, k;
short *q;
u.y = x;
#ifdef UNK
mtherr( "frexp", DOMAIN );
return(0.0L);
#endif
/* find the exponent (power of 2) */
#ifdef IBMPC
q = (short *)&u.sh[4];
i = *q & 0x7fff;
#endif
#ifdef MIEEE
q = (short *)&u.sh[0];
i = *q & 0x7fff;
#endif
if( i == 0 )
{
if( u.y == 0.0L )
{
*pw2 = 0;
return(0.0L);
}
/* Number is denormal or zero */
#ifdef DENORMAL
/* Handle denormal number. */
do
{
u.y *= 2.0L;
i -= 1;
k = *q & 0x7fff;
}
while( (k == 0) && (i > -66) );
i = i + k;
#else
*pw2 = 0;
return(0.0L);
#endif /* DENORMAL */
}
*pw2 = i - 0x3ffe;
*q = 0x3ffe;
return( u.y );
}
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