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Diffstat (limited to 'contrib/libgmp/mpz/ior.c')
| -rw-r--r-- | contrib/libgmp/mpz/ior.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/contrib/libgmp/mpz/ior.c b/contrib/libgmp/mpz/ior.c new file mode 100644 index 0000000..77facfd --- /dev/null +++ b/contrib/libgmp/mpz/ior.c @@ -0,0 +1,243 @@ +/* mpz_ior -- Logical inclusive or. + +Copyright (C) 1991, 1993, 1994, 1996 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_ior (mpz_ptr res, mpz_srcptr op1, mpz_srcptr op2) +#else +mpz_ior (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) + { + if (op1_size >= op2_size) + { + if (res->_mp_alloc < op1_size) + { + _mpz_realloc (res, op1_size); + op1_ptr = op1->_mp_d; + op2_ptr = op2->_mp_d; + res_ptr = res->_mp_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->_mp_alloc < op2_size) + { + _mpz_realloc (res, op2_size); + op1_ptr = op1->_mp_d; + op2_ptr = op2->_mp_d; + res_ptr = res->_mp_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->_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; + + /* 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) TMP_ALLOC (res_size * BYTES_PER_MP_LIMB); + mpn_sub_1 (opx, op1_ptr, res_size, (mp_limb_t) 1); + op1_ptr = opx; + + opx = (mp_ptr) TMP_ALLOC (res_size * BYTES_PER_MP_LIMB); + mpn_sub_1 (opx, op2_ptr, res_size, (mp_limb_t) 1); + op2_ptr = opx; + + if (res->_mp_alloc < res_size) + { + _mpz_realloc (res, res_size); + 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. */ + } + + /* 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; + + if (res_size != 0) + { + /* Second loop computes the real result. */ + for (i = res_size - 1; i >= 0; i--) + res_ptr[i] = op1_ptr[i] & op2_ptr[i]; + + cy = mpn_add_1 (res_ptr, res_ptr, res_size, (mp_limb_t) 1); + if (cy) + { + res_ptr[res_size] = cy; + res_size++; + } + } + else + { + res_ptr[0] = 1; + res_size = 1; + } + + 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 t = op1; op1 = op2; op2 = t;} + {mp_srcptr t = op1_ptr; op1_ptr = op2_ptr; op2_ptr = t;} + {mp_size_t t = op1_size; op1_size = op2_size; op2_size = t;} + } + } + + { + mp_ptr opx; + mp_limb_t cy; + mp_size_t res_alloc; + mp_size_t count; + + /* 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) 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); + op1_ptr = op1->_mp_d; + res_ptr = res->_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. */ + } + + 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; + count = res_size; + } + 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); + count = op1_size; + } + + if (res_size != 0) + { + /* Second loop computes the real result. */ + for (i = count - 1; i >= 0; i--) + res_ptr[i] = ~op1_ptr[i] & op2_ptr[i]; + + cy = mpn_add_1 (res_ptr, res_ptr, res_size, (mp_limb_t) 1); + if (cy) + { + res_ptr[res_size] = cy; + res_size++; + } + } + else + { + res_ptr[0] = 1; + res_size = 1; + } + + res->_mp_size = -res_size; + } + TMP_FREE (marker); +} |
