freebsd-dev/contrib/libgmp/mpz/set_d.c
Mark Murray aa9bc17601 Clean import of libgmp 2.0.2, with only the non-x86 bits removed.
BMakefiles and other bits will follow.

Requested by:	Andrey Chernov
Made world by:	Chuck Robey
1996-10-20 08:49:26 +00:00

94 lines
2.0 KiB
C

/* mpz_set_d(integer, val) -- Assign INTEGER with a double value VAL.
Copyright (C) 1995 Free Software Foundation, Inc.
This file is part of the GNU MP Library.
The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
The GNU MP Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
License for more details.
You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include "gmp.h"
#include "gmp-impl.h"
void
#if __STDC__
mpz_set_d (mpz_ptr r, double d)
#else
mpz_set_d (r, d)
mpz_ptr r;
double d;
#endif
{
int negative;
mp_size_t size;
mp_limb_t tp[3];
mp_ptr rp;
negative = d < 0;
d = ABS (d);
/* Handle small arguments quickly. */
if (d < MP_BASE_AS_DOUBLE)
{
mp_limb_t tmp;
tmp = d;
PTR(r)[0] = tmp;
SIZ(r) = negative ? -(tmp != 0) : (tmp != 0);
return;
}
size = __gmp_extract_double (tp, d);
if (ALLOC(r) < size)
_mpz_realloc (r, size);
rp = PTR (r);
#if BITS_PER_MP_LIMB == 32
switch (size)
{
default:
MPN_ZERO (rp, size - 3);
rp += size - 3;
case 3:
rp[2] = tp[2];
rp[1] = tp[1];
rp[0] = tp[0];
break;
case 2:
rp[1] = tp[2];
rp[0] = tp[1];
break;
case 1:
abort ();
}
#else
switch (size)
{
default:
MPN_ZERO (rp, size - 2);
rp += size - 2;
case 2:
rp[1] = tp[1];
rp[0] = tp[0];
break;
case 1:
abort ();
}
#endif
SIZ(r) = negative ? -size : size;
}