--- /dev/null
+/* mpz_ior -- Logical inclusive or.
+
+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 "gmp.h"
+#include "gmp-impl.h"
+
+#define min(l,o) ((l) < (o) ? (l) : (o))
+#define max(h,i) ((h) > (i) ? (h) : (i))
+
+void
+#ifdef __STDC__
+mpz_ior (MP_INT *res, const MP_INT *op1, const MP_INT *op2)
+#else
+mpz_ior (res, op1, op2)
+ MP_INT *res;
+ const MP_INT *op1;
+ const MP_INT *op2;
+#endif
+{
+ mp_srcptr op1_ptr, op2_ptr;
+ mp_size op1_size, op2_size;
+ mp_ptr res_ptr;
+ mp_size res_size;
+ mp_size i;
+
+ op1_size = op1->size;
+ op2_size = op2->size;
+
+ op1_ptr = op1->d;
+ op2_ptr = op2->d;
+ res_ptr = res->d;
+
+ if (op1_size >= 0)
+ {
+ if (op2_size >= 0)
+ {
+ if (op1_size >= op2_size)
+ {
+ if (res->alloc < op1_size)
+ {
+ _mpz_realloc (res, op1_size);
+ op1_ptr = op1->d;
+ op2_ptr = op2->d;
+ res_ptr = res->d;
+ }
+
+ if (res_ptr != op1_ptr)
+ 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
+ {
+ if (res->alloc < op2_size)
+ {
+ _mpz_realloc (res, op2_size);
+ op1_ptr = op1->d;
+ op2_ptr = op2->d;
+ res_ptr = res->d;
+ }
+
+ if (res_ptr != op2_ptr)
+ 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;
+ }
+
+ res->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 cy;
+ mp_limb one = 1;
+
+ /* 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 */
+
+ op1_size = -op1_size;
+ op2_size = -op2_size;
+
+ res_size = min (op1_size, op2_size);
+
+ /* Possible optimization: Decrease mpn_sub precision,
+ as we won't use the entire res of both. */
+ opx = (mp_ptr) alloca (op1_size * BYTES_PER_MP_LIMB);
+ op1_size += mpn_sub (opx, op1_ptr, op1_size, &one, 1);
+ op1_ptr = opx;
+
+ opx = (mp_ptr) alloca (op2_size * BYTES_PER_MP_LIMB);
+ op2_size += mpn_sub (opx, op2_ptr, op2_size, &one, 1);
+ op2_ptr = opx;
+
+ if (res->alloc < res_size)
+ {
+ _mpz_realloc (res, res_size);
+ res_ptr = res->d;
+ /* Don't re-read OP1_PTR and OP2_PTR. They point to
+ temporary space--never to the space RES->D used
+ to point to before reallocation. */
+ }
+
+ /* 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;
+
+ /* Second loop computes the real result. */
+ for (i = res_size - 1; i >= 0; i--)
+ res_ptr[i] = op1_ptr[i] & op2_ptr[i];
+
+ if (res_size != 0)
+ {
+ cy = mpn_add (res_ptr, res_ptr, res_size, &one, 1);
+ if (cy)
+ {
+ res_ptr[res_size] = cy;
+ res_size++;
+ }
+ }
+ else
+ {
+ res_ptr[0] = 1;
+ res_size = 1;
+ }
+
+ res->size = -res_size;
+ return;
+ }
+ else
+ {
+ /* We should compute -OP1 | OP2. Swap OP1 and OP2 and fall
+ through to the code that handles OP1 | -OP2. */
+ {const MP_INT *t = op1; op1 = op2; op2 = t;}
+ {mp_srcptr t = op1_ptr; op1_ptr = op2_ptr; op2_ptr = t;}
+ {mp_size t = op1_size; op1_size = op2_size; op2_size = t;}
+ }
+ }
+
+ {
+ mp_ptr opx;
+ mp_limb cy;
+ mp_limb one = 1;
+ mp_size res_alloc;
+
+ /* Operand 2 negative, so will be the result.
+ -(OP1 | (-OP2)) = -(OP1 | ~(OP2 - 1)) =
+ = ~(OP1 | ~(OP2 - 1)) + 1 =
+ = (~OP1 & (OP2 - 1)) + 1 */
+
+ op2_size = -op2_size;
+
+ res_alloc = op2_size;
+
+ opx = (mp_ptr) alloca (op2_size * BYTES_PER_MP_LIMB);
+ op2_size += mpn_sub (opx, op2_ptr, op2_size, &one, 1);
+ op2_ptr = opx;
+
+ if (res->alloc < res_alloc)
+ {
+ _mpz_realloc (res, res_alloc);
+ op1_ptr = op1->d;
+ res_ptr = res->d;
+ /* Don't re-read OP2_PTR. It points to temporary space--never
+ to the space RES->D used to point to before reallocation. */
+ }
+
+ if (op1_size >= op2_size)
+ {
+ /* We can just ignore the part of OP1 that stretches above OP2,
+ because the result limbs are zero there. */
+
+ /* First loop finds the size of the result. */
+ for (i = op2_size - 1; i >= 0; i--)
+ if ((~op1_ptr[i] & op2_ptr[i]) != 0)
+ break;
+ res_size = i + 1;
+ }
+ else
+ {
+ res_size = op2_size;
+
+ /* Copy the part of OP2 that stretches above OP1, to RES. */
+ MPN_COPY (res_ptr + op1_size, op2_ptr + op1_size,
+ op2_size - op1_size);
+ }
+
+ /* Second loop computes the real result. */
+ for (i = res_size - 1; i >= 0; i--)
+ res_ptr[i] = ~op1_ptr[i] & op2_ptr[i];
+
+ if (res_size != 0)
+ {
+ cy = mpn_add (res_ptr, res_ptr, res_size, &one, 1);
+ if (cy)
+ {
+ res_ptr[res_size] = cy;
+ res_size++;
+ }
+ }
+ else
+ {
+ res_ptr[0] = 1;
+ res_size = 1;
+ }
+
+ res->size = -res_size;
+ alloca (0);
+ return;
+ }
+}
projects / ghc-hetmet.git / blobdiff