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
27 * Simple depth first search on CFGs.
33 #define DISABLE_STATEV
43 static int cmp_edge(const void *a, const void *b, size_t sz)
45 const dfs_edge_t *p = a;
46 const dfs_edge_t *q = b;
49 return !(p->src == q->src && p->tgt == q->tgt);
52 static int cmp_node(const void *a, const void *b, size_t sz)
54 const dfs_node_t *p = a;
55 const dfs_node_t *q = b;
58 return p->node != q->node;
61 #define get_node(dfs, node) _dfs_get_node(dfs, node)
63 static dfs_edge_t *get_edge(const dfs_t *self, const void *src, const void *tgt)
65 unsigned hash = HASH_COMBINE(HASH_PTR(src), HASH_PTR(tgt));
72 return set_insert(self->edges, &templ, sizeof(templ), hash);
75 static void dfs_perform(dfs_t *dfs, void *n, void *anc, int level)
77 dfs_node_t *node = get_node(dfs, n);
80 assert(node->visited == 0);
85 node->pre_num = dfs->pre_num++;
86 node->max_pre_num = node->pre_num;
89 dfs->graph_impl->grow_succs(dfs->graph, n, &dfs->obst);
90 obstack_ptr_grow(&dfs->obst, NULL);
91 succs = obstack_finish(&dfs->obst);
93 for (iter = succs; *iter; ++iter) {
97 dfs_node_t *child = get_node(dfs, p);
99 /* create the edge object */
100 dfs_edge_t *edge = get_edge(dfs, n, p);
105 dfs_perform(dfs, p, node, level + 1);
107 /* get the maximum pre num of the subtree. needed for ancestor determination. */
108 node->max_pre_num = MAX(node->max_pre_num, child->max_pre_num);
111 node->post_num = dfs->post_num++;
112 obstack_free(&dfs->obst, succs);
115 static void classify_edges(dfs_t *dfs)
118 stat_ev_cnt_decl(anc);
119 stat_ev_cnt_decl(back);
120 stat_ev_cnt_decl(fwd);
121 stat_ev_cnt_decl(cross);
123 foreach_set (dfs->edges, edge) {
124 dfs_node_t *src = edge->s;
125 dfs_node_t *tgt = edge->t;
127 if (tgt->ancestor == src) {
128 stat_ev_cnt_inc(anc);
129 edge->kind = DFS_EDGE_ANC;
131 else if (_dfs_int_is_ancestor(tgt, src)) {
132 stat_ev_cnt_inc(back);
133 edge->kind = DFS_EDGE_BACK;
135 else if (_dfs_int_is_ancestor(src, tgt)) {
136 stat_ev_cnt_inc(fwd);
137 edge->kind = DFS_EDGE_FWD;
140 stat_ev_cnt_inc(cross);
141 edge->kind = DFS_EDGE_CROSS;
145 stat_ev_cnt_done(anc, "dfs_edge_anc");
146 stat_ev_cnt_done(back, "dfs_edge_back");
147 stat_ev_cnt_done(fwd, "dfs_edge_fwd");
148 stat_ev_cnt_done(cross, "dfs_edge_cross");
151 dfs_edge_kind_t dfs_get_edge_kind(const dfs_t *dfs, const void *a, const void *b)
153 if (!dfs->edges_classified) {
154 dfs_t *urg = (dfs_t *) dfs;
156 urg->edges_classified = 1;
158 return get_edge(dfs, a, b)->kind;
161 dfs_t *dfs_new(const absgraph_t *graph_impl, void *graph_self)
163 dfs_t *res = XMALLOC(dfs_t);
166 res->graph_impl = graph_impl;
167 res->graph = graph_self;
168 res->nodes = new_set(cmp_node, 64);
169 res->edges = new_set(cmp_edge, 128);
173 res->edges_classified = 0;
175 obstack_init(&res->obst);
177 dfs_perform(res, graph_impl->get_root(graph_self), NULL, 0);
179 /* make sure the end node (which might not be accessible) has a number */
180 node = get_node(res, graph_impl->get_end(graph_self));
181 if (!node->visited) {
183 node->node = graph_impl->get_end(graph_self);
184 node->ancestor = NULL;
185 node->pre_num = res->pre_num++;
186 node->post_num = res->post_num++;
187 node->max_pre_num = node->pre_num;
193 assert(res->pre_num == res->post_num);
194 res->pre_order = XMALLOCN(dfs_node_t*, res->pre_num);
195 res->post_order = XMALLOCN(dfs_node_t*, res->post_num);
196 foreach_set (res->nodes, node) {
197 assert(node->pre_num < res->pre_num);
198 assert(node->post_num < res->post_num);
200 res->pre_order[node->pre_num] = node;
201 res->post_order[node->post_num] = node;
204 stat_ev_dbl("dfs_n_blocks", res->pre_num);
209 void dfs_free(dfs_t *dfs)
213 xfree(dfs->pre_order);
214 xfree(dfs->post_order);
218 static void dfs_dump_edge(const dfs_edge_t *edge, FILE *file)
220 dfs_node_t *src = edge->s;
221 dfs_node_t *tgt = edge->t;
222 const char *s, *style;
225 #define XXX(e) case DFS_EDGE_ ## e: s = #e; break
226 switch (edge->kind) {
234 weight = edge->kind == DFS_EDGE_BACK ? 1 : 1000;
235 style = edge->kind == DFS_EDGE_BACK ? "dashed" : "solid";
237 ir_fprintf(file, "\tn%d -> n%d [label=\"%s\",style=\"%s\",weight=\"%d\"];\n", src->pre_num, tgt->pre_num, s, style, weight);
240 static int node_level_cmp(const void *a, const void *b)
242 const dfs_node_t *p = *(const dfs_node_t **) a;
243 const dfs_node_t *q = *(const dfs_node_t **) b;
245 if (p->level == q->level)
246 return p->pre_num - q->pre_num;
247 return p->level - q->level;
250 void dfs_dump(const dfs_t *dfs, FILE *file)
252 dfs_node_t **nodes = XMALLOCN(dfs_node_t*, dfs->pre_num);
257 ir_fprintf(file, "digraph G {\nranksep=0.5\n");
258 foreach_set (dfs->nodes, node) {
262 qsort(nodes, n, sizeof(nodes[0]), node_level_cmp);
266 int level = nodes[i]->level;
268 ir_fprintf(file, "\t{ rank = same; ");
269 for (; i < n && nodes[i]->level == level; ++i)
270 ir_fprintf(file, "n%d;", nodes[i]->pre_num);
271 ir_fprintf(file, "}\n");
276 for (i = 0; i < n; ++i) {
277 dfs_node_t *node = nodes[i];
278 ir_fprintf(file, "\tn%d [label=\"%d\"]\n", node->pre_num, get_Block_dom_tree_pre_num(node->node));
280 ir_fprintf(file, "\tn%d [shape=box,label=\"%+F\\l%d %d/%d %d\"];\n",
281 node->pre_num, node->node, get_Block_dom_tree_pre_num(node->node),
282 node->pre_num, node->post_num, node->max_pre_num);
286 foreach_set (dfs->edges, edge)
287 dfs_dump_edge(edge, file);
289 ir_fprintf(file, "}\n");