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 * @brief Functions for traversing ir graphs
23 * @author Boris Boesler, Goetz Lindenmaier, Michael Beck
26 * traverse an ir graph
27 * - execute the pre function before recursion
28 * - execute the post function after recursion
39 #include "irgraph_t.h" /* visited flag */
49 * Walk over an interprocedural graph (callgraph).
50 * Visits only graphs in irg_set.
52 static void irg_walk_cg(ir_node * node, unsigned long visited,
53 pset_new_t *irg_set, irg_walk_func *pre,
54 irg_walk_func *post, void * env) {
56 ir_graph * rem = current_ir_graph;
59 assert(node && node->kind == k_ir_node);
60 if (get_irn_visited(node) >= visited) return;
62 set_irn_visited(node, visited);
64 if (pre) pre(node, env);
66 pred = skip_Proj(node);
67 if (get_irn_op(pred) == op_CallBegin
68 || get_irn_op(pred) == op_EndReg
69 || get_irn_op(pred) == op_EndExcept) {
70 current_ir_graph = get_irn_irg(pred);
73 if (is_no_Block(node)) { /* not block */
74 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
77 if (get_irn_op(node) == op_Block) { /* block */
78 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
79 ir_node * exec = get_irn_n(node, i);
80 ir_node * pred = skip_Proj(exec);
81 if ((get_irn_op(pred) != op_CallBegin
82 && get_irn_op(pred) != op_EndReg
83 && get_irn_op(pred) != op_EndExcept)
84 || pset_new_contains(irg_set, get_irn_irg(pred))) {
85 irg_walk_cg(exec, visited, irg_set, pre, post, env);
88 } else if (get_irn_op(node) == op_Filter) { /* filter */
89 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
90 ir_node * pred = get_irn_n(node, i);
91 if (get_irn_op(pred) == op_Unknown || get_irn_op(pred) == op_Bad) {
92 irg_walk_cg(pred, visited, irg_set, pre, post, env);
95 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
97 if (op_Bad == get_irn_op (exec)) {
101 assert(get_irn_op(exec) == op_CallBegin
102 || get_irn_op(exec) == op_EndReg
103 || get_irn_op(exec) == op_EndExcept);
104 if (pset_new_contains(irg_set, get_irn_irg(exec))) {
105 current_ir_graph = get_irn_irg(exec);
106 irg_walk_cg(pred, visited, irg_set, pre, post, env);
107 current_ir_graph = rem;
111 } else { /* everything else */
112 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
113 irg_walk_cg(get_irn_n(node, i), visited, irg_set, pre, post, env);
117 if (post) post(node, env);
119 current_ir_graph = rem;
124 * Insert all ir_graphs in irg_set, that are (transitive) reachable.
126 static void collect_irgs(ir_node * node, pset_new_t *irg_set) {
129 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
130 ir_entity * ent = get_Call_callee(node, i);
131 ir_graph * irg = get_entity_irg(ent);
132 if (irg && !pset_new_contains(irg_set, irg)) {
133 pset_new_insert(irg_set, irg);
134 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
141 * specialized version of irg_walk_2, called if only pre callback exists
143 * @return number of visited nodes
146 irg_walk_2_pre(ir_node *node, irg_walk_func *pre, void * env) {
149 ir_graph *irg = current_ir_graph;
151 set_irn_visited(node, irg->visited);
155 if (node->op != op_Block) {
156 ir_node *pred = get_irn_n(node, -1);
157 if (pred->visited < irg->visited)
158 cnt += irg_walk_2_pre(pred, pre, env);
160 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
161 ir_node *pred = get_irn_n(node, i);
162 if (pred->visited < irg->visited)
163 cnt += irg_walk_2_pre(pred, pre, env);
169 * specialized version of irg_walk_2, called if only post callback exists
171 * @return number of visited nodes
174 irg_walk_2_post(ir_node *node, irg_walk_func *post, void * env) {
177 ir_graph *irg = current_ir_graph;
179 set_irn_visited(node, irg->visited);
181 if (node->op != op_Block) {
182 ir_node *pred = get_irn_n(node, -1);
183 if (pred->visited < irg->visited)
184 cnt += irg_walk_2_post(pred, post, env);
186 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
187 ir_node *pred = get_irn_n(node, i);
188 if (pred->visited < irg->visited)
189 cnt += irg_walk_2_post(pred, post, env);
198 * specialized version of irg_walk_2, called if pre and post callbacks exist
200 * @return number of visited nodes
203 irg_walk_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env) {
206 ir_graph *irg = current_ir_graph;
208 set_irn_visited(node, irg->visited);
212 if (node->op != op_Block) {
213 ir_node *pred = get_irn_n(node, -1);
214 if (pred->visited < irg->visited)
215 cnt += irg_walk_2_both(pred, pre, post, env);
217 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
218 ir_node *pred = get_irn_n(node, i);
219 if (pred->visited < irg->visited)
220 cnt += irg_walk_2_both(pred, pre, post, env);
229 * Intraprozedural graph walker.
231 * @return number of visited nodes
234 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
236 if (node->visited < current_ir_graph->visited) {
237 if (!post) return irg_walk_2_pre (node, pre, env);
238 else if (!pre) return irg_walk_2_post(node, post, env);
239 else return irg_walk_2_both(node, pre, post, env);
245 static unsigned nodes_touched = 0;
248 * generic graph walker
250 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
252 assert(is_ir_node(node));
254 if (get_interprocedural_view()) {
256 pset_new_iterator_t iter;
257 unsigned long visited;
259 assert(get_irp_ip_view_state() == ip_view_valid);
261 pset_new_init(&irg_set);
262 set_interprocedural_view(0);
263 pset_new_insert(&irg_set, current_ir_graph);
264 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, &irg_set);
265 set_interprocedural_view(1);
266 visited = get_max_irg_visited() + 1;
268 foreach_pset_new(&irg_set, irg, iter) {
269 set_irg_visited(irg, visited);
271 irg_walk_cg(node, visited, &irg_set, pre, post, env);
272 pset_new_destroy(&irg_set);
274 set_using_visited(current_ir_graph);
275 inc_irg_visited(current_ir_graph);
276 nodes_touched = irg_walk_2(node, pre, post, env);
277 clear_using_visited(current_ir_graph);
285 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
286 ir_graph * rem = current_ir_graph;
288 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
289 current_ir_graph = irg;
290 irg_walk(get_irg_end(irg), pre, post, env);
291 irg->estimated_node_count = nodes_touched;
292 current_ir_graph = rem;
295 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
296 Sets current_ir_graph properly for each walk. Conserves current
298 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
302 for (i = 0, n = get_irp_n_irgs(); i < n; i++) {
303 irg = get_irp_irg(i);
304 irg_walk_graph(irg, pre, post, env);
308 /***************************************************************************/
311 * specialized version of irg_walk_in_or_dep_2, called if only pre callback exists
313 * @return number of visited nodes
316 irg_walk_in_or_dep_2_pre(ir_node *node, irg_walk_func *pre, void *env) {
319 ir_graph *irg = current_ir_graph;
321 set_irn_visited(node, irg->visited);
325 if (node->op != op_Block) {
326 ir_node *pred = get_irn_n(node, -1);
327 if (pred->visited < irg->visited)
328 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
330 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
331 ir_node *pred = get_irn_in_or_dep(node, i);
332 if (pred->visited < irg->visited)
333 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
339 * specialized version of irg_walk_in_or_dep_2, called if only post callback exists
341 * @return number of visited nodes
344 irg_walk_in_or_dep_2_post(ir_node *node, irg_walk_func *post, void *env) {
347 ir_graph *irg = current_ir_graph;
349 set_irn_visited(node, irg->visited);
351 if (node->op != op_Block) {
352 ir_node *pred = get_irn_n(node, -1);
353 if (pred->visited < irg->visited)
354 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
356 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
357 ir_node *pred = get_irn_in_or_dep(node, i);
358 if (pred->visited < irg->visited)
359 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
368 * specialized version of irg_walk_in_or_dep_2, called if pre and post callbacks exist
370 * @return number of visited nodes
373 irg_walk_in_or_dep_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env) {
376 ir_graph *irg = current_ir_graph;
378 set_irn_visited(node, irg->visited);
382 if (node->op != op_Block) {
383 ir_node *pred = get_irn_n(node, -1);
384 if (pred->visited < irg->visited)
385 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
387 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
388 ir_node *pred = get_irn_in_or_dep(node, i);
389 if (pred->visited < irg->visited)
390 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
399 * Intraprozedural graph walker. Follows dependency edges as well.
401 * @return number of visited nodes
404 irg_walk_in_or_dep_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
406 if (node->visited < current_ir_graph->visited) {
407 if (! post) return irg_walk_in_or_dep_2_pre (node, pre, env);
408 else if (! pre) return irg_walk_in_or_dep_2_post(node, post, env);
409 else return irg_walk_in_or_dep_2_both(node, pre, post, env);
415 * Generic graph walker. Follows dependency edges as well.
417 void irg_walk_in_or_dep(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
419 assert(is_ir_node(node));
421 if (get_interprocedural_view()) {
422 assert(0 && "This is not yet implemented.");
424 set_using_visited(current_ir_graph);
425 inc_irg_visited(current_ir_graph);
426 nodes_touched = irg_walk_in_or_dep_2(node, pre, post, env);
427 clear_using_visited(current_ir_graph);
433 * Walk over a graph. Follow all edges (including dependencies)
435 void irg_walk_in_or_dep_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
436 ir_graph * rem = current_ir_graph;
438 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
439 current_ir_graph = irg;
440 irg_walk_in_or_dep(get_irg_end(irg), pre, post, env);
441 irg->estimated_node_count = nodes_touched;
442 current_ir_graph = rem;
445 /***************************************************************************/
448 * Returns current_ir_graph and sets it to the irg of predecessor index
451 static INLINE ir_graph *
452 switch_irg(ir_node *n, int index) {
453 ir_graph *old_current = current_ir_graph;
455 if (get_interprocedural_view()) {
456 /* Only Filter and Block nodes can have predecessors in other graphs. */
457 if (get_irn_op(n) == op_Filter)
458 n = get_nodes_block(n);
459 if (get_irn_op(n) == op_Block) {
460 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
461 if (is_ip_cfop(cfop)) {
462 current_ir_graph = get_irn_irg(cfop);
471 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
474 ir_graph *rem = NULL;
477 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
478 set_irn_visited(node, get_irg_visited(current_ir_graph));
480 if (pre) pre(node, env);
482 if (is_no_Block(node))
483 cg_walk_2(get_nodes_block(node), pre, post, env);
484 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
485 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
486 switch to the irg of the predecessor, don't we? */
487 cg_walk_2(get_irn_n(node, i), pre, post, env);
488 current_ir_graph = rem;
491 if (post) post(node, env);
497 /* Walks all irgs in interprocedural view. Visits each node only once. */
498 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
500 ir_graph *rem = current_ir_graph;
501 int rem_view = get_interprocedural_view();
503 set_interprocedural_view(1);
505 inc_max_irg_visited();
506 /* Fix all irg_visited flags */
507 for (i = 0; i < get_irp_n_irgs(); i++)
508 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
510 /* Walk starting at unreachable procedures. Only these
511 * have End blocks visible in interprocedural view. */
512 for (i = 0; i < get_irp_n_irgs(); i++) {
514 current_ir_graph = get_irp_irg(i);
516 sb = get_irg_start_block(current_ir_graph);
518 if ((get_Block_n_cfgpreds(sb) > 1) ||
519 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
521 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
524 /* Check whether we walked all procedures: there could be procedures
525 with cyclic calls but no call from the outside. */
526 for (i = 0; i < get_irp_n_irgs(); i++) {
528 current_ir_graph = get_irp_irg(i);
530 /* Test start block: if inner procedure end and end block are not
531 * visible and therefore not marked. */
532 sb = get_irg_start_block(current_ir_graph);
533 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
534 cg_walk_2(sb, pre, post, env);
538 /* Walk all endless loops in inner procedures.
539 * We recognize an inner procedure if the End node is not visited. */
540 for (i = 0; i < get_irp_n_irgs(); i++) {
542 current_ir_graph = get_irp_irg(i);
543 e = get_irg_end(current_ir_graph);
544 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
546 /* Don't visit the End node. */
547 for (j = 0; j < get_End_n_keepalives(e); j++)
548 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
552 set_interprocedural_view(rem_view);
553 current_ir_graph = rem;
557 /***************************************************************************/
559 /* Walks back from n until it finds a real cf op. */
560 static ir_node *get_cf_op(ir_node *n) {
566 if (!(is_cfop(pred) || is_fragile_op(pred) || is_Bad(pred)))
572 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
576 if (Block_not_block_visited(node)) {
577 mark_Block_block_visited(node);
579 if(pre) pre(node, env);
581 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
582 /* find the corresponding predecessor block. */
583 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
584 pred = get_nodes_block(pred);
585 if(get_irn_opcode(pred) == iro_Block) {
587 irg_block_walk_2(pred, pre, post, env);
590 assert(get_irn_opcode(pred) == iro_Bad);
594 if(post) post(node, env);
599 /* walks only over Block nodes in the graph. Has it's own visited
600 flag, so that it can be interleaved with the other walker. */
601 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
603 ir_node *block, *pred;
606 hook_irg_block_walk(current_ir_graph, node, (generic_func *)pre, (generic_func *)post);
609 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
610 * interleaves with irg_walk */
611 set_using_block_visited(current_ir_graph);
612 inc_irg_block_visited(current_ir_graph);
613 block = is_Block(node) ? node : get_nodes_block(node);
614 assert(get_irn_op(block) == op_Block);
615 irg_block_walk_2(block, pre, post, env);
617 /* keepalive: the endless loops ... */
618 if (get_irn_op(node) == op_End) {
619 int arity = get_irn_arity(node);
620 for (i = 0; i < arity; i++) {
621 pred = get_irn_n(node, i);
622 if (get_irn_op(pred) == op_Block)
623 irg_block_walk_2(pred, pre, post, env);
625 /* Sometimes the blocks died, but are still reachable through Phis.
626 * Make sure the algorithms that try to remove these reach them. */
627 for (i = 0; i < arity; i++) {
628 pred = get_irn_n(node, i);
629 if (get_irn_op(pred) == op_Phi) {
630 ir_node *block = get_nodes_block(pred);
633 irg_block_walk_2(block, pre, post, env);
638 clear_using_block_visited(current_ir_graph);
642 * walk over a graph block wise
644 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
645 irg_walk_func *post, void *env) {
646 ir_graph * rem = current_ir_graph;
647 current_ir_graph = irg;
648 irg_block_walk(get_irg_end(irg), pre, post, env);
649 current_ir_graph = rem;
653 * Additionally walk over all anchors. Do NOT increase the visit flag.
655 void irg_walk_anchors(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
656 ir_graph * rem = current_ir_graph;
657 current_ir_graph = irg;
659 inc_irg_visited(irg);
660 irg_walk_2(irg->anchor, pre, post, env);
662 current_ir_graph = rem;
665 /********************************************************************/
667 typedef struct walk_env {
674 * Walk to all constant expressions in this entity.
676 static void walk_entity(ir_entity *ent, void *env)
678 walk_env *my_env = (walk_env *)env;
680 if (get_entity_variability(ent) != variability_uninitialized) {
681 if (is_atomic_entity(ent)) {
682 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
684 int i, n_vals = get_compound_ent_n_values(ent);
686 for (i = 0; i < n_vals; i++)
687 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
692 /* Walks over all code in const_code_irg. */
693 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
697 ir_graph *rem = current_ir_graph;
698 current_ir_graph = get_const_code_irg();
699 inc_irg_visited(current_ir_graph);
705 /* Walk all types that can contain constant entities. */
706 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
707 n_types = get_irp_n_types();
708 for (i = 0; i < n_types; i++)
709 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
710 for (i = 0; i < get_irp_n_irgs(); i++)
711 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
713 /* Walk constant array bounds. */
714 for (i = 0; i < n_types; i++) {
715 ir_type *tp = get_irp_type(i);
716 if (is_Array_type(tp)) {
717 int n_dim = get_array_n_dimensions(tp);
718 for (j = 0; j < n_dim; j++) {
719 ir_node *n = get_array_lower_bound(tp, j);
720 if (n) irg_walk(n, pre, post, env);
721 n = get_array_upper_bound(tp, j);
722 if (n) irg_walk(n, pre, post, env);
727 current_ir_graph = rem;