2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @author Sebastian Hack
27 * Simple depth first search on CFGs.
43 static const char *edge_names[] = {
50 static int cmp_edge(const void *a, const void *b, size_t sz)
52 const dfs_edge_t *p = a;
53 const dfs_edge_t *q = b;
56 return !(p->src == q->src && p->tgt == q->tgt);
59 static int cmp_node(const void *a, const void *b, size_t sz)
61 const dfs_node_t *p = a;
62 const dfs_node_t *q = b;
65 return p->node != q->node;
68 #define get_node(dfs, node) _dfs_get_node(dfs, node)
70 static dfs_edge_t *get_edge(const dfs_t *self, const void *src, const void *tgt)
72 unsigned hash = HASH_COMBINE(HASH_PTR(src), HASH_PTR(tgt));
79 return set_insert(self->edges, &templ, sizeof(templ), hash);
82 static void dfs_perform(dfs_t *dfs, void *n, void *anc, int level)
84 dfs_node_t *node = get_node(dfs, n);
87 assert(node->visited == 0);
92 node->pre_num = dfs->pre_num++;
93 node->max_pre_num = node->pre_num;
96 dfs->graph_impl->grow_succs(dfs->graph, n, &dfs->obst);
97 obstack_ptr_grow(&dfs->obst, NULL);
98 succs = obstack_finish(&dfs->obst);
100 for (iter = succs; *iter; ++iter) {
104 dfs_node_t *child = get_node(dfs, p);
106 /* create the edge object */
107 dfs_edge_t *edge = get_edge(dfs, n, p);
112 dfs_perform(dfs, p, node, level + 1);
114 /* get the maximum pre num of the subtree. needed for ancestor determination. */
115 node->max_pre_num = MAX(node->max_pre_num, child->max_pre_num);
118 node->post_num = dfs->post_num++;
119 obstack_free(&dfs->obst, succs);
122 static void classify_edges(dfs_t *dfs)
124 stat_ev_cnt_decl(anc);
125 stat_ev_cnt_decl(back);
126 stat_ev_cnt_decl(fwd);
127 stat_ev_cnt_decl(cross);
130 foreach_set (dfs->edges, edge) {
131 dfs_node_t *src = edge->s;
132 dfs_node_t *tgt = edge->t;
134 if (tgt->ancestor == src) {
135 stat_ev_cnt_inc(anc);
136 edge->kind = DFS_EDGE_ANC;
138 else if (_dfs_int_is_ancestor(tgt, src)) {
139 stat_ev_cnt_inc(back);
140 edge->kind = DFS_EDGE_BACK;
142 else if (_dfs_int_is_ancestor(src, tgt)) {
143 stat_ev_cnt_inc(fwd);
144 edge->kind = DFS_EDGE_FWD;
147 stat_ev_cnt_inc(cross);
148 edge->kind = DFS_EDGE_CROSS;
152 stat_ev_cnt_done(anc, "dfs_edge_anc");
153 stat_ev_cnt_done(back, "dfs_edge_back");
154 stat_ev_cnt_done(fwd, "dfs_edge_fwd");
155 stat_ev_cnt_done(cross, "dfs_edge_cross");
158 dfs_edge_kind_t dfs_get_edge_kind(const dfs_t *dfs, const void *a, const void *b)
160 if (!dfs->edges_classified) {
161 dfs_t *urg = (dfs_t *) dfs;
163 urg->edges_classified = 1;
165 return get_edge(dfs, a, b)->kind;
168 dfs_t *dfs_new(const absgraph_t *graph_impl, void *graph_self)
170 dfs_t *res = xmalloc(sizeof(res[0]));
173 res->graph_impl = graph_impl;
174 res->graph = graph_self;
175 res->nodes = new_set(cmp_node, 64);
176 res->edges = new_set(cmp_edge, 128);
180 res->edges_classified = 0;
182 obstack_init(&res->obst);
184 dfs_perform(res, graph_impl->get_root(graph_self), NULL, 0);
187 res->pre_order = xmalloc(res->pre_num * sizeof(res->pre_order));
188 res->post_order = xmalloc(res->pre_num * sizeof(res->post_order));
189 foreach_set (res->nodes, node) {
190 res->pre_order[node->pre_num] = node;
191 res->post_order[node->post_num] = node;
194 stat_ev_dbl("dfs_n_blocks", res->pre_num);
199 void dfs_free(dfs_t *dfs)
203 xfree(dfs->pre_order);
204 xfree(dfs->post_order);
208 static void dfs_dump_edge(const dfs_edge_t *edge, FILE *file)
210 dfs_node_t *src = edge->s;
211 dfs_node_t *tgt = edge->t;
212 const char *s, *style;
215 #define XXX(e) case DFS_EDGE_ ## e: s = #e; break
216 switch (edge->kind) {
224 weight = edge->kind == DFS_EDGE_BACK ? 1 : 1000;
225 style = edge->kind == DFS_EDGE_BACK ? "dashed" : "solid";
227 ir_fprintf(file, "\tn%d -> n%d [label=\"%s\",style=\"%s\",weight=\"%d\"];\n", src->pre_num, tgt->pre_num, s, style, weight);
230 static int node_level_cmp(const void *a, const void *b)
232 const dfs_node_t *p = *(const dfs_node_t **) a;
233 const dfs_node_t *q = *(const dfs_node_t **) b;
235 if (p->level == q->level)
236 return p->pre_num - q->pre_num;
237 return p->level - q->level;
240 void dfs_dump(const dfs_t *dfs, FILE *file)
242 dfs_node_t **nodes = xmalloc(dfs->pre_num * sizeof(nodes[0]));
247 ir_fprintf(file, "digraph G {\nranksep=0.5\n");
248 foreach_set (dfs->nodes, node) {
252 qsort(nodes, n, sizeof(nodes[0]), node_level_cmp);
256 int level = nodes[i]->level;
258 ir_fprintf(file, "\t{ rank = same; ");
259 for (; i < n && nodes[i]->level == level; ++i)
260 ir_fprintf(file, "n%d;", nodes[i]->pre_num);
261 ir_fprintf(file, "}\n");
266 for (i = 0; i < n; ++i) {
267 dfs_node_t *node = nodes[i];
268 ir_fprintf(file, "\tn%d [label=\"%d\"]\n", node->pre_num, get_Block_dom_tree_pre_num(node->node));
270 ir_fprintf(file, "\tn%d [shape=box,label=\"%+F\\l%d %d/%d %d\"];\n",
271 node->pre_num, node->node, get_Block_dom_tree_pre_num(node->node),
272 node->pre_num, node->post_num, node->max_pre_num);
276 foreach_set (dfs->edges, edge)
277 dfs_dump_edge(edge, file);
279 ir_fprintf(file, "}\n");