1 /* Box class implementation (non-inline functions).
2 Copyright (C) 2001-2010 Roberto Bagnara <bagnara@cs.unipr.it>
3 Copyright (C) 2010-2016 BUGSENG srl (http://bugseng.com)
4
5 This file is part of the Parma Polyhedra Library (PPL).
6
7 The PPL is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 3 of the License, or (at your
10 option) any later version.
11
12 The PPL is distributed in the hope that it will be useful, but WITHOUT
13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software Foundation,
19 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1307, USA.
20
21 For the most up-to-date information see the Parma Polyhedra Library
22 site: http://bugseng.com/products/ppl/ . */
23
24 #include "ppl-config.h"
25 #include "Box_defs.hh"
26
27 namespace PPL = Parma_Polyhedra_Library;
28
29 bool
extract_interval_constraint(const Constraint & c,dimension_type & c_num_vars,dimension_type & c_only_var)30 PPL::Box_Helpers::extract_interval_constraint(const Constraint& c,
31 dimension_type& c_num_vars,
32 dimension_type& c_only_var) {
33 // Check for preconditions.
34 PPL_ASSERT(c_num_vars == 0 && c_only_var == 0);
35
36 c_only_var = c.expression().first_nonzero(1, c.space_dimension() + 1);
37 if (c_only_var == c.space_dimension() + 1) {
38 // All the inhomogeneous coefficients are zero.
39 return true;
40 }
41
42 ++c_num_vars;
43 --c_only_var;
44 return c.expression().all_zeroes(c_only_var + 2, c.space_dimension() + 1);
45 }
46
47 bool
extract_interval_congruence(const Congruence & cg,dimension_type & cg_num_vars,dimension_type & cg_only_var)48 PPL::Box_Helpers::extract_interval_congruence(const Congruence& cg,
49 dimension_type& cg_num_vars,
50 dimension_type& cg_only_var) {
51 // Check for preconditions.
52 PPL_ASSERT(cg_num_vars == 0 && cg_only_var == 0);
53 // Only equality congruences can be intervals.
54 PPL_ASSERT(cg.is_equality());
55
56 cg_only_var = cg.expression().first_nonzero(1, cg.space_dimension() + 1);
57 if (cg_only_var == cg.space_dimension() + 1) {
58 // All the inhomogeneous coefficients are zero.
59 return true;
60 }
61
62 ++cg_num_vars;
63 --cg_only_var;
64 return cg.expression().all_zeroes(cg_only_var + 2, cg.space_dimension() + 1);
65 }
66