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/* (c) PolKA project at Inria Lorraine */
#include <stdio.h>
#include "gmp.h"
#include "gmp-impl.h"
#include "longlong.h"
#include "mpfr.h"
/* returns a positive value if b>i*2^f,
a negative value if b<i*2^f,
zero if b=i*2^f
*/
int
#if __STDC__
mpfr_cmp_ui_2exp ( mpfr_srcptr b, unsigned long int i, int f )
#else
mpfr_cmp_ui_2exp (b, i, f)
mpfr_srcptr b;
unsigned long int i;
int f;
#endif
{
int e, k, bn; mp_limb_t c, *bp;
if (SIGN(b)<0) return -1;
else if (!NOTZERO(b)) return((i) ? -1 : 0);
else { /* b>0 */
e = EXP(b); /* 2^(e-1) <= b < 2^e */
if (e>f+mp_bits_per_limb) return 1;
c = (mp_limb_t) i;
count_leading_zeros(k, c);
k = f+mp_bits_per_limb - k; /* 2^(k-1) <= i*2^f < 2^k */
if (k!=e) return (e-k);
/* now k=e */
c <<= (f+mp_bits_per_limb-k);
bn = (PREC(b)-1)/mp_bits_per_limb;
bp = MANT(b) + bn;
if (*bp>c) return 1;
else if (*bp<c) return -1;
/* most significant limbs agree, check remaining limbs from b */
while (--bn>=0)
if (*--bp) return 1;
return 0;
}
}
/* returns a positive value if b>i*2^f,
a negative value if b<i*2^f,
zero if b=i*2^f
*/
int
#if __STDC__
mpfr_cmp_si_2exp ( mpfr_srcptr b, long int i, int f )
#else
mpfr_cmp_si_2exp(b, i, f)
mpfr_srcptr b;
long int i;
int f;
#endif
{
int e, k, bn, si; mp_limb_t c, *bp;
si = (i<0) ? -1 : 1; /* sign of i */
if (SIGN(b)*i<0) return SIGN(b); /* both signs differ */
else if (!NOTZERO(b) || (i==0)) { /* one is zero */
if (i==0) return ((NOTZERO(b)) ? SIGN(b) : 0);
else return si; /* b is zero */
}
else { /* b and i are of same sign */
e = EXP(b); /* 2^(e-1) <= b < 2^e */
if (e>f+mp_bits_per_limb) return si;
c = (mp_limb_t) ((i<0) ? -i : i);
count_leading_zeros(k, c);
k = f+mp_bits_per_limb - k; /* 2^(k-1) <= i*2^f < 2^k */
if (k!=e) return (si*(e-k));
/* now k=e */
c <<= (f+mp_bits_per_limb-k);
bn = (PREC(b)-1)/mp_bits_per_limb;
bp = MANT(b) + bn;
if (*bp>c) return si;
else if (*bp<c) return -si;
/* most significant limbs agree, check remaining limbs from b */
while (--bn>=0)
if (*--bp) return si;
return 0;
}
}
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