1 /* Template classes for directed graphs.
2 Copyright (C) 2019-2020 Free Software Foundation, Inc.
3 Contributed by David Malcolm <dmalcolm@redhat.com>.
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
11
12 GCC is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
20
21 #include "config.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "diagnostic.h"
25 #include "graphviz.h"
26 #include "digraph.h"
27 #include "shortest-paths.h"
28 #include "selftest.h"
29
30 #if CHECKING_P
31
32 namespace selftest {
33
34 /* A family of digraph classes for writing selftests. */
35
36 struct test_node;
37 struct test_edge;
38 struct test_graph;
39 struct test_dump_args_t {};
40 struct test_cluster;
41
42 struct test_graph_traits
43 {
44 typedef test_node node_t;
45 typedef test_edge edge_t;
46 typedef test_graph graph_t;
47 typedef test_dump_args_t dump_args_t;
48 typedef test_cluster cluster_t;
49 };
50
51 struct test_node : public dnode<test_graph_traits>
52 {
test_nodeselftest::test_node53 test_node (const char *name, int index) : m_name (name), m_index (index) {}
dump_dotselftest::test_node54 void dump_dot (graphviz_out *, const dump_args_t &) const OVERRIDE
55 {
56 }
57
58 const char *m_name;
59 int m_index;
60 };
61
62 struct test_edge : public dedge<test_graph_traits>
63 {
test_edgeselftest::test_edge64 test_edge (node_t *src, node_t *dest)
65 : dedge<test_graph_traits> (src, dest)
66 {}
67
dump_dotselftest::test_edge68 void dump_dot (graphviz_out *gv, const dump_args_t &) const OVERRIDE
69 {
70 gv->println ("%s -> %s;", m_src->m_name, m_dest->m_name);
71 }
72 };
73
74 struct test_graph : public digraph<test_graph_traits>
75 {
add_test_nodeselftest::test_graph76 test_node *add_test_node (const char *name)
77 {
78 test_node *result = new test_node (name, m_nodes.length ());
79 add_node (result);
80 return result;
81 }
82
add_test_edgeselftest::test_graph83 test_edge *add_test_edge (test_node *src, test_node *dst)
84 {
85 test_edge *result = new test_edge (src, dst);
86 add_edge (result);
87 return result;
88 }
89 };
90
91 struct test_cluster : public cluster<test_graph_traits>
92 {
93 };
94
95 struct test_path
96 {
97 auto_vec<const test_edge *> m_edges;
98 };
99
100 /* Smoketest of digraph dumping. */
101
102 static void
test_dump_to_dot()103 test_dump_to_dot ()
104 {
105 test_graph g;
106 test_node *a = g.add_test_node ("a");
107 test_node *b = g.add_test_node ("b");
108 g.add_test_edge (a, b);
109
110 pretty_printer pp;
111 pp.buffer->stream = NULL;
112 test_dump_args_t dump_args;
113 g.dump_dot_to_pp (&pp, NULL, dump_args);
114
115 ASSERT_STR_CONTAINS (pp_formatted_text (&pp),
116 "a -> b;\n");
117 }
118
119 /* Test shortest paths from A in this digraph,
120 where edges run top-to-bottom if not otherwise labeled:
121
122 A
123 / \
124 B C-->D
125 | |
126 E |
127 \ /
128 F. */
129
130 static void
test_shortest_paths()131 test_shortest_paths ()
132 {
133 test_graph g;
134 test_node *a = g.add_test_node ("a");
135 test_node *b = g.add_test_node ("b");
136 test_node *c = g.add_test_node ("d");
137 test_node *d = g.add_test_node ("d");
138 test_node *e = g.add_test_node ("e");
139 test_node *f = g.add_test_node ("f");
140
141 test_edge *ab = g.add_test_edge (a, b);
142 test_edge *ac = g.add_test_edge (a, c);
143 test_edge *cd = g.add_test_edge (c, d);
144 test_edge *be = g.add_test_edge (b, e);
145 g.add_test_edge (e, f);
146 test_edge *cf = g.add_test_edge (c, f);
147
148 shortest_paths<test_graph_traits, test_path> sp (g, a);
149
150 test_path path_to_a = sp.get_shortest_path (a);
151 ASSERT_EQ (path_to_a.m_edges.length (), 0);
152
153 test_path path_to_b = sp.get_shortest_path (b);
154 ASSERT_EQ (path_to_b.m_edges.length (), 1);
155 ASSERT_EQ (path_to_b.m_edges[0], ab);
156
157 test_path path_to_c = sp.get_shortest_path (c);
158 ASSERT_EQ (path_to_c.m_edges.length (), 1);
159 ASSERT_EQ (path_to_c.m_edges[0], ac);
160
161 test_path path_to_d = sp.get_shortest_path (d);
162 ASSERT_EQ (path_to_d.m_edges.length (), 2);
163 ASSERT_EQ (path_to_d.m_edges[0], ac);
164 ASSERT_EQ (path_to_d.m_edges[1], cd);
165
166 test_path path_to_e = sp.get_shortest_path (e);
167 ASSERT_EQ (path_to_e.m_edges.length (), 2);
168 ASSERT_EQ (path_to_e.m_edges[0], ab);
169 ASSERT_EQ (path_to_e.m_edges[1], be);
170
171 test_path path_to_f = sp.get_shortest_path (f);
172 ASSERT_EQ (path_to_f.m_edges.length (), 2);
173 ASSERT_EQ (path_to_f.m_edges[0], ac);
174 ASSERT_EQ (path_to_f.m_edges[1], cf);
175 }
176
177 /* Run all of the selftests within this file. */
178
179 void
digraph_cc_tests()180 digraph_cc_tests ()
181 {
182 test_dump_to_dot ();
183 test_shortest_paths ();
184 }
185
186 } // namespace selftest
187
188 #endif /* #if CHECKING_P */
189