diff options
Diffstat (limited to 'vendor/gmp-6.3.0/mpz/ior.c')
| -rw-r--r-- | vendor/gmp-6.3.0/mpz/ior.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpz/ior.c b/vendor/gmp-6.3.0/mpz/ior.c new file mode 100644 index 0000000..32f3042 --- /dev/null +++ b/vendor/gmp-6.3.0/mpz/ior.c @@ -0,0 +1,184 @@ +/* mpz_ior -- Logical inclusive or. + +Copyright 1991, 1993, 1994, 1996, 1997, 2000, 2001, 2005, 2012, 2013, +2015-2018 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 either: + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at your + option) any later version. + +or + + * the GNU General Public License as published by the Free Software + Foundation; either version 2 of the License, or (at your option) any + later version. + +or both in parallel, as here. + +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 copies of the GNU General Public License and the +GNU Lesser General Public License along with the GNU MP Library. If not, +see https://www.gnu.org/licenses/. */ + +#include "gmp-impl.h" + +void +mpz_ior (mpz_ptr res, mpz_srcptr op1, mpz_srcptr op2) +{ + 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; + + op1_size = SIZ(op1); + op2_size = SIZ(op2); + + if (op1_size < op2_size) + { + MPZ_SRCPTR_SWAP (op1, op2); + MP_SIZE_T_SWAP (op1_size, op2_size); + } + + op1_ptr = PTR(op1); + res_ptr = PTR(res); + + if (op2_size >= 0) + { + if (res_ptr != op1_ptr) + { + res_ptr = MPZ_REALLOC (res, op1_size); + /* No overlapping possible: op1_ptr = PTR(op1); */ + MPN_COPY (res_ptr + op2_size, op1_ptr + op2_size, + op1_size - op2_size); + } + if (LIKELY (op2_size != 0)) + mpn_ior_n (res_ptr, op1_ptr, PTR(op2), op2_size); + + SIZ(res) = op1_size; + } + else + { + mp_ptr opx; + TMP_DECL; + + TMP_MARK; + if (op1_size < 0) + { + mp_ptr opy; + + /* 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 */ + + res_size = -op1_size; + + /* Possible optimization: Decrease mpn_sub precision, + as we won't use the entire res of both. */ + TMP_ALLOC_LIMBS_2 (opx, res_size, opy, res_size); + mpn_sub_1 (opx, op1_ptr, res_size, (mp_limb_t) 1); + op1_ptr = opx; + + mpn_sub_1 (opy, PTR(op2), res_size, (mp_limb_t) 1); + op2_ptr = opy; + + /* First loop finds the size of the result. */ + for (i = res_size; --i >= 0;) + if ((op1_ptr[i] & op2_ptr[i]) != 0) + break; + res_size = i + 1; + + res_ptr = MPZ_NEWALLOC (res, res_size + 1); + + if (res_size != 0) + { + /* Second loop computes the real result. */ + mpn_and_n (res_ptr, op1_ptr, op2_ptr, res_size); + + res_ptr[res_size] = 0; + MPN_INCR_U (res_ptr, res_size + 1, 1); + res_size += res_ptr[res_size]; + } + else + { + res_ptr[0] = 1; + res_size = 1; + } + + SIZ(res) = -res_size; + } + else + { + mp_limb_t cy; + 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_ptr = MPZ_REALLOC (res, op2_size); + op1_ptr = PTR(op1); + + opx = TMP_ALLOC_LIMBS (op2_size); + mpn_sub_1 (opx, PTR(op2), op2_size, (mp_limb_t) 1); + op2_ptr = opx; + op2_size -= op2_ptr[op2_size - 1] == 0; + + 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; --i >= 0;) + 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. */ + if (LIKELY (count != 0)) + mpn_andn_n (res_ptr, op2_ptr, op1_ptr, count); + + 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; + } + + SIZ(res) = -res_size; + } + TMP_FREE; + } +} |