stk/Mp/gmp-1.3.2/sdiv.c

77 lines
2.3 KiB
C

/* sdiv -- Divide a MINT by a short integer. Produce a MINT quotient
and a short remainder.
Copyright (C) 1991 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 General Public License as published by
the Free Software Foundation; either version 2, 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with the GNU MP Library; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "mp.h"
#include "gmp.h"
#include "gmp-impl.h"
#include "longlong.h"
void
#ifdef __STDC__
sdiv (const MINT *dividend, signed short int divisor_short, MINT *quot, short *rem_ptr)
#else
sdiv (dividend, divisor_short, quot, rem_ptr)
const MINT *dividend;
short int divisor_short;
MINT *quot;
short *rem_ptr;
#endif
{
mp_size sign_dividend;
signed long int sign_divisor;
mp_size dividend_size, quot_size;
mp_ptr dividend_ptr, quot_ptr;
mp_limb divisor_limb;
mp_limb remainder_limb;
sign_dividend = dividend->size;
dividend_size = ABS (dividend->size);
if (dividend_size == 0)
{
quot->size = 0;
*rem_ptr = 0;
return;
}
sign_divisor = divisor_short;
divisor_limb = ABS (divisor_short);
/* No need for temporary allocation and copying even if QUOT == DIVIDEND
as the divisor is just one limb, and thus no intermediate remainders
need to be stored. */
if (quot->alloc < dividend_size)
_mpz_realloc (quot, dividend_size);
quot_ptr = quot->d;
dividend_ptr = dividend->d;
remainder_limb = mpn_divmod_1 (quot_ptr,
dividend_ptr, dividend_size, divisor_limb);
*rem_ptr = sign_dividend >= 0 ? remainder_limb : -remainder_limb;
/* The quotient is DIVIDEND_SIZE limbs, but the most significant
might be zero. Set QUOT_SIZE properly. */
quot_size = dividend_size - (quot_ptr[dividend_size - 1] == 0);
quot->size = (sign_divisor ^ sign_dividend) >= 0 ? quot_size : -quot_size;
}