+++ /dev/null
-/* mpz_and -- Logical and.
-
-Copyright (C) 1991, 1993, 1994, 1996, 1997, 2000 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 Lesser General Public License as published by
-the Free Software Foundation; either version 2.1 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 Lesser General Public
-License for more details.
-
-You should have received a copy of the GNU Lesser 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_and (mpz_ptr res, mpz_srcptr op1, mpz_srcptr op2)
-#else
-mpz_and (res, op1, op2)
- mpz_ptr res;
- mpz_srcptr op1;
- mpz_srcptr op2;
-#endif
-{
- mp_srcptr op1_ptr, op2_ptr;
- mp_size_t op1_size, op2_size;
- mp_ptr res_ptr;
- mp_size_t res_size;
- mp_size_t i;
- TMP_DECL (marker);
-
- TMP_MARK (marker);
- op1_size = op1->_mp_size;
- op2_size = op2->_mp_size;
-
- op1_ptr = op1->_mp_d;
- op2_ptr = op2->_mp_d;
- res_ptr = res->_mp_d;
-
- if (op1_size >= 0)
- {
- if (op2_size >= 0)
- {
- res_size = MIN (op1_size, op2_size);
- /* First loop finds the size of the result. */
- for (i = res_size - 1; i >= 0; i--)
- if ((op1_ptr[i] & op2_ptr[i]) != 0)
- break;
- res_size = i + 1;
-
- /* Handle allocation, now then we know exactly how much space is
- needed for the result. */
- if (res->_mp_alloc < res_size)
- {
- _mpz_realloc (res, res_size);
- op1_ptr = op1->_mp_d;
- op2_ptr = op2->_mp_d;
- res_ptr = res->_mp_d;
- }
-
- /* Second loop computes the real result. */
- for (i = res_size - 1; i >= 0; i--)
- res_ptr[i] = op1_ptr[i] & op2_ptr[i];
-
- res->_mp_size = res_size;
- return;
- }
- else /* op2_size < 0 */
- {
- /* Fall through to the code at the end of the function. */
- }
- }
- else
- {
- if (op2_size < 0)
- {
- mp_ptr opx;
- mp_limb_t cy;
- mp_size_t res_alloc;
-
- /* Both operands are negative, so will be the result.
- -((-OP1) & (-OP2)) = -(~(OP1 - 1) & ~(OP2 - 1)) =
- = ~(~(OP1 - 1) & ~(OP2 - 1)) + 1 =
- = ((OP1 - 1) | (OP2 - 1)) + 1 */
-
- /* It might seem as we could end up with an (invalid) result with
- a leading zero-limb here when one of the operands is of the
- type 1,,0,,..,,.0. But some analysis shows that we surely
- would get carry into the zero-limb in this situation... */
-
- op1_size = -op1_size;
- op2_size = -op2_size;
-
- res_alloc = 1 + MAX (op1_size, op2_size);
-
- opx = (mp_ptr) TMP_ALLOC (op1_size * BYTES_PER_MP_LIMB);
- mpn_sub_1 (opx, op1_ptr, op1_size, (mp_limb_t) 1);
- op1_ptr = opx;
-
- opx = (mp_ptr) TMP_ALLOC (op2_size * BYTES_PER_MP_LIMB);
- mpn_sub_1 (opx, op2_ptr, op2_size, (mp_limb_t) 1);
- op2_ptr = opx;
-
- if (res->_mp_alloc < res_alloc)
- {
- _mpz_realloc (res, res_alloc);
- res_ptr = res->_mp_d;
- /* Don't re-read OP1_PTR and OP2_PTR. They point to
- temporary space--never to the space RES->_mp_d used
- to point to before reallocation. */
- }
-
- if (op1_size >= op2_size)
- {
- MPN_COPY (res_ptr + op2_size, op1_ptr + op2_size,
- op1_size - op2_size);
- for (i = op2_size - 1; i >= 0; i--)
- res_ptr[i] = op1_ptr[i] | op2_ptr[i];
- res_size = op1_size;
- }
- else
- {
- MPN_COPY (res_ptr + op1_size, op2_ptr + op1_size,
- op2_size - op1_size);
- for (i = op1_size - 1; i >= 0; i--)
- res_ptr[i] = op1_ptr[i] | op2_ptr[i];
- res_size = op2_size;
- }
-
- cy = mpn_add_1 (res_ptr, res_ptr, res_size, (mp_limb_t) 1);
- if (cy)
- {
- res_ptr[res_size] = cy;
- res_size++;
- }
-
- res->_mp_size = -res_size;
- TMP_FREE (marker);
- return;
- }
- else
- {
- /* We should compute -OP1 & OP2. Swap OP1 and OP2 and fall
- through to the code that handles OP1 & -OP2. */
- MPZ_SRCPTR_SWAP (op1, op2);
- MPN_SRCPTR_SWAP (op1_ptr,op1_size, op2_ptr,op2_size);
- }
-
- }
-
- {
-#if ANDNEW
- mp_size_t op2_lim;
- mp_size_t count;
-
- /* OP2 must be negated as with infinite precision.
-
- Scan from the low end for a non-zero limb. The first non-zero
- limb is simply negated (two's complement). Any subsequent
- limbs are one's complemented. Of course, we don't need to
- handle more limbs than there are limbs in the other, positive
- operand as the result for those limbs is going to become zero
- anyway. */
-
- /* Scan for the least significant non-zero OP2 limb, and zero the
- result meanwhile for those limb positions. (We will surely
- find a non-zero limb, so we can write the loop with one
- termination condition only.) */
- for (i = 0; op2_ptr[i] == 0; i++)
- res_ptr[i] = 0;
- op2_lim = i;
-
- op2_size = -op2_size;
-
- if (op1_size <= op2_size)
- {
- /* The ones-extended OP2 is >= than the zero-extended OP1.
- RES_SIZE <= OP1_SIZE. Find the exact size. */
- for (i = op1_size - 1; i > op2_lim; i--)
- if ((op1_ptr[i] & ~op2_ptr[i]) != 0)
- break;
- res_size = i + 1;
- for (i = res_size - 1; i > op2_lim; i--)
- res_ptr[i] = op1_ptr[i] & ~op2_ptr[i];
- res_ptr[op2_lim] = op1_ptr[op2_lim] & -op2_ptr[op2_lim];
- /* Yes, this *can* happen! */
- MPN_NORMALIZE (res_ptr, res_size);
- }
- else
- {
- /* The ones-extended OP2 is < than the zero-extended OP1.
- RES_SIZE == OP1_SIZE, since OP1 is normalized. */
- res_size = op1_size;
- MPN_COPY (res_ptr + op2_size, op1_ptr + op2_size, op1_size - op2_size);
- for (i = op2_size - 1; i > op2_lim; i--)
- res_ptr[i] = op1_ptr[i] & ~op2_ptr[i];
- res_ptr[op2_lim] = op1_ptr[op2_lim] & -op2_ptr[op2_lim];
- }
-
- res->_mp_size = res_size;
-#else
-
- /* OP1 is positive and zero-extended,
- OP2 is negative and ones-extended.
- The result will be positive.
- OP1 & -OP2 = OP1 & ~(OP2 - 1). */
-
- mp_ptr opx;
-
- op2_size = -op2_size;
- opx = (mp_ptr) TMP_ALLOC (op2_size * BYTES_PER_MP_LIMB);
- mpn_sub_1 (opx, op2_ptr, op2_size, (mp_limb_t) 1);
- op2_ptr = opx;
-
- if (op1_size > op2_size)
- {
- /* The result has the same size as OP1, since OP1 is normalized
- and longer than the ones-extended OP2. */
- res_size = op1_size;
-
- /* Handle allocation, now then we know exactly how much space is
- needed for the result. */
- if (res->_mp_alloc < res_size)
- {
- _mpz_realloc (res, res_size);
- res_ptr = res->_mp_d;
- op1_ptr = op1->_mp_d;
- /* Don't re-read OP2_PTR. It points to temporary space--never
- to the space RES->_mp_d used to point to before reallocation. */
- }
-
- MPN_COPY (res_ptr + op2_size, op1_ptr + op2_size,
- res_size - op2_size);
- for (i = op2_size - 1; i >= 0; i--)
- res_ptr[i] = op1_ptr[i] & ~op2_ptr[i];
-
- res->_mp_size = res_size;
- }
- else
- {
- /* Find out the exact result size. Ignore the high limbs of OP2,
- OP1 is zero-extended and would make the result zero. */
- for (i = op1_size - 1; i >= 0; i--)
- if ((op1_ptr[i] & ~op2_ptr[i]) != 0)
- break;
- res_size = i + 1;
-
- /* Handle allocation, now then we know exactly how much space is
- needed for the result. */
- if (res->_mp_alloc < res_size)
- {
- _mpz_realloc (res, res_size);
- res_ptr = res->_mp_d;
- op1_ptr = op1->_mp_d;
- /* Don't re-read OP2_PTR. It points to temporary space--never
- to the space RES->_mp_d used to point to before reallocation. */
- }
-
- for (i = res_size - 1; i >= 0; i--)
- res_ptr[i] = op1_ptr[i] & ~op2_ptr[i];
-
- res->_mp_size = res_size;
- }
-#endif
- }
- TMP_FREE (marker);
-}
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