2 * Copyright (C) 1995-2008 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
26 * Simple depth first search on CFGs.
32 #define DISABLE_STATEV
42 static int cmp_edge(const void *a, const void *b, size_t sz)
44 const dfs_edge_t *p = (const dfs_edge_t*) a;
45 const dfs_edge_t *q = (const dfs_edge_t*) b;
48 return !(p->src == q->src && p->tgt == q->tgt);
51 static int cmp_node(const void *a, const void *b, size_t sz)
53 const dfs_node_t *p = (const dfs_node_t*) a;
54 const dfs_node_t *q = (const dfs_node_t*) b;
57 return p->node != q->node;
60 #define get_node(dfs, node) _dfs_get_node(dfs, node)
62 static dfs_edge_t *get_edge(const dfs_t *self, const void *src, const void *tgt)
64 unsigned hash = hash_combine(hash_ptr(src), hash_ptr(tgt));
69 templ.kind = (dfs_edge_kind_t) -1;
71 return set_insert(dfs_edge_t, self->edges, &templ, sizeof(templ), hash);
74 static void dfs_perform(dfs_t *dfs, void *n, void *anc, int level)
76 dfs_node_t *node = get_node(dfs, n);
79 assert(node->visited == 0);
84 node->pre_num = dfs->pre_num++;
85 node->max_pre_num = node->pre_num;
88 dfs->graph_impl->grow_succs(dfs->graph, n, &dfs->obst);
89 obstack_ptr_grow(&dfs->obst, NULL);
90 succs = (void**) obstack_finish(&dfs->obst);
92 for (iter = succs; *iter; ++iter) {
96 dfs_node_t *child = get_node(dfs, p);
98 /* create the edge object */
99 dfs_edge_t *edge = get_edge(dfs, n, p);
104 dfs_perform(dfs, p, node, level + 1);
106 /* get the maximum pre num of the subtree. needed for ancestor determination. */
107 node->max_pre_num = MAX(node->max_pre_num, child->max_pre_num);
110 node->post_num = dfs->post_num++;
111 obstack_free(&dfs->obst, succs);
114 static void classify_edges(dfs_t *dfs)
116 stat_ev_cnt_decl(anc);
117 stat_ev_cnt_decl(back);
118 stat_ev_cnt_decl(fwd);
119 stat_ev_cnt_decl(cross);
121 foreach_set (dfs->edges, dfs_edge_t, edge) {
122 dfs_node_t *src = edge->s;
123 dfs_node_t *tgt = edge->t;
125 if (tgt->ancestor == src) {
126 stat_ev_cnt_inc(anc);
127 edge->kind = DFS_EDGE_ANC;
129 else if (_dfs_int_is_ancestor(tgt, src)) {
130 stat_ev_cnt_inc(back);
131 edge->kind = DFS_EDGE_BACK;
133 else if (_dfs_int_is_ancestor(src, tgt)) {
134 stat_ev_cnt_inc(fwd);
135 edge->kind = DFS_EDGE_FWD;
138 stat_ev_cnt_inc(cross);
139 edge->kind = DFS_EDGE_CROSS;
143 stat_ev_cnt_done(anc, "dfs_edge_anc");
144 stat_ev_cnt_done(back, "dfs_edge_back");
145 stat_ev_cnt_done(fwd, "dfs_edge_fwd");
146 stat_ev_cnt_done(cross, "dfs_edge_cross");
149 dfs_edge_kind_t dfs_get_edge_kind(const dfs_t *dfs, const void *a, const void *b)
151 if (!dfs->edges_classified) {
152 dfs_t *urg = (dfs_t *) dfs;
154 urg->edges_classified = 1;
156 return get_edge(dfs, a, b)->kind;
159 dfs_t *dfs_new(const absgraph_t *graph_impl, void *graph_self)
161 dfs_t *res = XMALLOC(dfs_t);
163 res->graph_impl = graph_impl;
164 res->graph = graph_self;
165 res->nodes = new_set(cmp_node, 64);
166 res->edges = new_set(cmp_edge, 128);
170 res->edges_classified = 0;
172 obstack_init(&res->obst);
174 dfs_perform(res, graph_impl->get_root(graph_self), NULL, 0);
176 /* make sure the end node (which might not be accessible) has a number */
177 dfs_node_t *const node = get_node(res, graph_impl->get_end(graph_self));
178 if (!node->visited) {
180 node->node = graph_impl->get_end(graph_self);
181 node->ancestor = NULL;
182 node->pre_num = res->pre_num++;
183 node->post_num = res->post_num++;
184 node->max_pre_num = node->pre_num;
190 assert(res->pre_num == res->post_num);
191 res->pre_order = XMALLOCN(dfs_node_t*, res->pre_num);
192 res->post_order = XMALLOCN(dfs_node_t*, res->post_num);
193 foreach_set (res->nodes, dfs_node_t, node) {
194 assert(node->pre_num < res->pre_num);
195 assert(node->post_num < res->post_num);
197 res->pre_order[node->pre_num] = node;
198 res->post_order[node->post_num] = node;
201 stat_ev_dbl("dfs_n_blocks", res->pre_num);
206 void dfs_free(dfs_t *dfs)
208 obstack_free(&dfs->obst, NULL);
211 xfree(dfs->pre_order);
212 xfree(dfs->post_order);
216 static void dfs_dump_edge(const dfs_edge_t *edge, FILE *file)
218 dfs_node_t *src = edge->s;
219 dfs_node_t *tgt = edge->t;
220 const char *s, *style;
223 #define XXX(e) case DFS_EDGE_ ## e: s = #e; break
224 switch (edge->kind) {
232 weight = edge->kind == DFS_EDGE_BACK ? 1 : 1000;
233 style = edge->kind == DFS_EDGE_BACK ? "dashed" : "solid";
235 ir_fprintf(file, "\tn%d -> n%d [label=\"%s\",style=\"%s\",weight=\"%d\"];\n", src->pre_num, tgt->pre_num, s, style, weight);
238 static int node_level_cmp(const void *a, const void *b)
240 const dfs_node_t *p = *(const dfs_node_t **) a;
241 const dfs_node_t *q = *(const dfs_node_t **) b;
243 if (p->level == q->level)
244 return p->pre_num - q->pre_num;
245 return p->level - q->level;
248 void dfs_dump(const dfs_t *dfs, FILE *file)
250 dfs_node_t **nodes = XMALLOCN(dfs_node_t*, dfs->pre_num);
253 ir_fprintf(file, "digraph G {\nranksep=0.5\n");
254 foreach_set (dfs->nodes, dfs_node_t, node) {
258 qsort(nodes, n, sizeof(nodes[0]), node_level_cmp);
262 int level = nodes[i]->level;
264 ir_fprintf(file, "\t{ rank = same; ");
265 for (; i < n && nodes[i]->level == level; ++i)
266 ir_fprintf(file, "n%d;", nodes[i]->pre_num);
267 ir_fprintf(file, "}\n");
272 for (i = 0; i < n; ++i) {
273 dfs_node_t *const node = nodes[i];
274 ir_fprintf(file, "\tn%d [label=\"%d\"]\n", node->pre_num, get_Block_dom_tree_pre_num((ir_node*) node->node));
276 ir_fprintf(file, "\tn%d [shape=box,label=\"%+F\\l%d %d/%d %d\"];\n",
277 node->pre_num, node->node, get_Block_dom_tree_pre_num(node->node),
278 node->pre_num, node->post_num, node->max_pre_num);
282 foreach_set (dfs->edges, dfs_edge_t, edge)
283 dfs_dump_edge(edge, file);
285 ir_fprintf(file, "}\n");