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 */
50 * Walk over an interprocedural graph (callgraph).
51 * Visits only graphs in irg_set.
53 static void irg_walk_cg(ir_node * node, unsigned long visited,
54 pset_new_t *irg_set, irg_walk_func *pre,
55 irg_walk_func *post, void * env) {
57 ir_graph * rem = current_ir_graph;
60 assert(node && node->kind == k_ir_node);
61 if (get_irn_visited(node) >= visited) return;
63 set_irn_visited(node, visited);
65 if (pre) pre(node, env);
67 pred = skip_Proj(node);
68 if (get_irn_op(pred) == op_CallBegin
69 || get_irn_op(pred) == op_EndReg
70 || get_irn_op(pred) == op_EndExcept) {
71 current_ir_graph = get_irn_irg(pred);
74 if (is_no_Block(node)) { /* not block */
75 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
78 if (get_irn_op(node) == op_Block) { /* block */
79 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
80 ir_node * exec = get_irn_n(node, i);
81 ir_node * pred = skip_Proj(exec);
82 if ((get_irn_op(pred) != op_CallBegin
83 && get_irn_op(pred) != op_EndReg
84 && get_irn_op(pred) != op_EndExcept)
85 || pset_new_contains(irg_set, get_irn_irg(pred))) {
86 irg_walk_cg(exec, visited, irg_set, pre, post, env);
89 } else if (get_irn_op(node) == op_Filter) { /* filter */
90 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
91 ir_node * pred = get_irn_n(node, i);
92 if (get_irn_op(pred) == op_Unknown || get_irn_op(pred) == op_Bad) {
93 irg_walk_cg(pred, visited, irg_set, pre, post, env);
96 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
98 if (op_Bad == get_irn_op (exec)) {
102 assert(get_irn_op(exec) == op_CallBegin
103 || get_irn_op(exec) == op_EndReg
104 || get_irn_op(exec) == op_EndExcept);
105 if (pset_new_contains(irg_set, get_irn_irg(exec))) {
106 current_ir_graph = get_irn_irg(exec);
107 irg_walk_cg(pred, visited, irg_set, pre, post, env);
108 current_ir_graph = rem;
112 } else { /* everything else */
113 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
114 irg_walk_cg(get_irn_n(node, i), visited, irg_set, pre, post, env);
118 if (post) post(node, env);
120 current_ir_graph = rem;
125 * Insert all ir_graphs in irg_set, that are (transitive) reachable.
127 static void collect_irgs(ir_node * node, pset_new_t *irg_set) {
130 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
131 ir_entity * ent = get_Call_callee(node, i);
132 ir_graph * irg = get_entity_irg(ent);
133 if (irg && !pset_new_contains(irg_set, irg)) {
134 pset_new_insert(irg_set, irg);
135 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
142 * specialized version of irg_walk_2, called if only pre callback exists
144 * @return number of visited nodes
147 irg_walk_2_pre(ir_node *node, irg_walk_func *pre, void * env) {
150 ir_graph *irg = current_ir_graph;
152 set_irn_visited(node, irg->visited);
156 if (node->op != op_Block) {
157 ir_node *pred = get_irn_n(node, -1);
158 if (pred->visited < irg->visited)
159 cnt += irg_walk_2_pre(pred, pre, env);
161 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
162 ir_node *pred = get_irn_n(node, i);
163 if (pred->visited < irg->visited)
164 cnt += irg_walk_2_pre(pred, pre, env);
170 * specialized version of irg_walk_2, called if only post callback exists
172 * @return number of visited nodes
175 irg_walk_2_post(ir_node *node, irg_walk_func *post, void * env) {
178 ir_graph *irg = current_ir_graph;
180 set_irn_visited(node, irg->visited);
182 if (node->op != op_Block) {
183 ir_node *pred = get_irn_n(node, -1);
184 if (pred->visited < irg->visited)
185 cnt += irg_walk_2_post(pred, post, env);
187 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
188 ir_node *pred = get_irn_n(node, i);
189 if (pred->visited < irg->visited)
190 cnt += irg_walk_2_post(pred, post, env);
199 * specialized version of irg_walk_2, called if pre and post callbacks exist
201 * @return number of visited nodes
204 irg_walk_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env) {
207 ir_graph *irg = current_ir_graph;
209 set_irn_visited(node, irg->visited);
213 if (node->op != op_Block) {
214 ir_node *pred = get_irn_n(node, -1);
215 if (pred->visited < irg->visited)
216 cnt += irg_walk_2_both(pred, pre, post, env);
218 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
219 ir_node *pred = get_irn_n(node, i);
220 if (pred->visited < irg->visited)
221 cnt += irg_walk_2_both(pred, pre, post, env);
230 * Intraprozedural graph walker.
232 * @return number of visited nodes
235 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
237 if (node->visited < current_ir_graph->visited) {
238 if (!post) return irg_walk_2_pre (node, pre, env);
239 else if (!pre) return irg_walk_2_post(node, post, env);
240 else return irg_walk_2_both(node, pre, post, env);
246 static unsigned nodes_touched = 0;
249 * generic graph walker
251 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
253 assert(is_ir_node(node));
255 if (get_interprocedural_view()) {
257 pset_new_iterator_t iter;
258 unsigned long visited;
260 assert(get_irp_ip_view_state() == ip_view_valid);
262 pset_new_init(&irg_set);
263 set_interprocedural_view(0);
264 pset_new_insert(&irg_set, current_ir_graph);
265 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, &irg_set);
266 set_interprocedural_view(1);
267 visited = get_max_irg_visited() + 1;
269 foreach_pset_new(&irg_set, irg, iter) {
270 set_irg_visited(irg, visited);
272 irg_walk_cg(node, visited, &irg_set, pre, post, env);
273 pset_new_destroy(&irg_set);
275 set_using_visited(current_ir_graph);
276 inc_irg_visited(current_ir_graph);
277 nodes_touched = irg_walk_2(node, pre, post, env);
278 clear_using_visited(current_ir_graph);
286 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
287 ir_graph * rem = current_ir_graph;
289 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
290 current_ir_graph = irg;
291 irg_walk(get_irg_end(irg), pre, post, env);
292 irg->estimated_node_count = nodes_touched;
293 current_ir_graph = rem;
296 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
297 Sets current_ir_graph properly for each walk. Conserves current
299 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
303 rem = current_ir_graph;
305 for (i = 0; i < get_irp_n_irgs(); i++) {
306 irg = get_irp_irg(i);
307 current_ir_graph = irg;
308 irg_walk(get_irg_end(irg), pre, post, env);
310 current_ir_graph = rem;
313 /***************************************************************************/
316 * specialized version of irg_walk_in_or_dep_2, called if only pre callback exists
318 * @return number of visited nodes
321 irg_walk_in_or_dep_2_pre(ir_node *node, irg_walk_func *pre, void *env) {
324 ir_graph *irg = current_ir_graph;
326 set_irn_visited(node, irg->visited);
330 if (node->op != op_Block) {
331 ir_node *pred = get_irn_n(node, -1);
332 if (pred->visited < irg->visited)
333 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
335 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
336 ir_node *pred = get_irn_in_or_dep(node, i);
337 if (pred->visited < irg->visited)
338 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
344 * specialized version of irg_walk_in_or_dep_2, called if only post callback exists
346 * @return number of visited nodes
349 irg_walk_in_or_dep_2_post(ir_node *node, irg_walk_func *post, void *env) {
352 ir_graph *irg = current_ir_graph;
354 set_irn_visited(node, irg->visited);
356 if (node->op != op_Block) {
357 ir_node *pred = get_irn_n(node, -1);
358 if (pred->visited < irg->visited)
359 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
361 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
362 ir_node *pred = get_irn_in_or_dep(node, i);
363 if (pred->visited < irg->visited)
364 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
373 * specialized version of irg_walk_in_or_dep_2, called if pre and post callbacks exist
375 * @return number of visited nodes
378 irg_walk_in_or_dep_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env) {
381 ir_graph *irg = current_ir_graph;
383 set_irn_visited(node, irg->visited);
387 if (node->op != op_Block) {
388 ir_node *pred = get_irn_n(node, -1);
389 if (pred->visited < irg->visited)
390 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
392 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
393 ir_node *pred = get_irn_in_or_dep(node, i);
394 if (pred->visited < irg->visited)
395 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
404 * Intraprozedural graph walker. Follows dependency edges as well.
406 * @return number of visited nodes
409 irg_walk_in_or_dep_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
411 if (node->visited < current_ir_graph->visited) {
412 if (! post) return irg_walk_in_or_dep_2_pre (node, pre, env);
413 else if (! pre) return irg_walk_in_or_dep_2_post(node, post, env);
414 else return irg_walk_in_or_dep_2_both(node, pre, post, env);
420 * Generic graph walker. Follows dependency edges as well.
422 void irg_walk_in_or_dep(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
424 assert(is_ir_node(node));
426 if (get_interprocedural_view()) {
427 assert(0 && "This is not yet implemented.");
429 set_using_visited(current_ir_graph);
430 inc_irg_visited(current_ir_graph);
431 nodes_touched = irg_walk_in_or_dep_2(node, pre, post, env);
432 clear_using_visited(current_ir_graph);
438 * Walk over a graph. Follow all edges (including dependencies)
440 void irg_walk_in_or_dep_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
441 ir_graph * rem = current_ir_graph;
443 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
444 current_ir_graph = irg;
445 irg_walk_in_or_dep(get_irg_end(irg), pre, post, env);
446 irg->estimated_node_count = nodes_touched;
447 current_ir_graph = rem;
450 /***************************************************************************/
453 * Returns current_ir_graph and sets it to the irg of predecessor index
456 static INLINE ir_graph *
457 switch_irg (ir_node *n, int index) {
458 ir_graph *old_current = current_ir_graph;
460 if (get_interprocedural_view()) {
461 /* Only Filter and Block nodes can have predecessors in other graphs. */
462 if (get_irn_op(n) == op_Filter)
463 n = get_nodes_block(n);
464 if (get_irn_op(n) == op_Block) {
465 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
466 if (is_ip_cfop(cfop)) {
467 current_ir_graph = get_irn_irg(cfop);
476 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
479 ir_graph *rem = NULL;
482 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
483 set_irn_visited(node, get_irg_visited(current_ir_graph));
485 if (pre) pre(node, env);
487 if (is_no_Block(node))
488 cg_walk_2(get_nodes_block(node), pre, post, env);
489 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
490 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
491 switch to the irg of the predecessor, don't we? */
492 cg_walk_2(get_irn_n(node, i), pre, post, env);
493 current_ir_graph = rem;
496 if (post) post(node, env);
502 /* Walks all irgs in interprocedural view. Visits each node only once. */
503 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
505 ir_graph *rem = current_ir_graph;
506 int rem_view = get_interprocedural_view();
508 set_interprocedural_view(1);
510 inc_max_irg_visited();
511 /* Fix all irg_visited flags */
512 for (i = 0; i < get_irp_n_irgs(); i++)
513 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
515 /* Walk starting at unreachable procedures. Only these
516 * have End blocks visible in interprocedural view. */
517 for (i = 0; i < get_irp_n_irgs(); i++) {
519 current_ir_graph = get_irp_irg(i);
521 sb = get_irg_start_block(current_ir_graph);
523 if ((get_Block_n_cfgpreds(sb) > 1) ||
524 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
526 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
529 /* Check whether we walked all procedures: there could be procedures
530 with cyclic calls but no call from the outside. */
531 for (i = 0; i < get_irp_n_irgs(); i++) {
533 current_ir_graph = get_irp_irg(i);
535 /* Test start block: if inner procedure end and end block are not
536 * visible and therefore not marked. */
537 sb = get_irg_start_block(current_ir_graph);
538 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
539 cg_walk_2(sb, pre, post, env);
543 /* Walk all endless loops in inner procedures.
544 * We recognize an inner procedure if the End node is not visited. */
545 for (i = 0; i < get_irp_n_irgs(); i++) {
547 current_ir_graph = get_irp_irg(i);
548 e = get_irg_end(current_ir_graph);
549 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
551 /* Don't visit the End node. */
552 for (j = 0; j < get_End_n_keepalives(e); j++)
553 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
557 set_interprocedural_view(rem_view);
558 current_ir_graph = rem;
562 /***************************************************************************/
564 /* Walks back from n until it finds a real cf op. */
565 static ir_node *get_cf_op(ir_node *n) {
571 if (!(is_cfop(pred) || is_fragile_op(pred) || is_Bad(pred)))
577 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
581 if (Block_not_block_visited(node)) {
582 mark_Block_block_visited(node);
584 if(pre) pre(node, env);
586 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
587 /* find the corresponding predecessor block. */
588 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
589 pred = get_nodes_block(pred);
590 if(get_irn_opcode(pred) == iro_Block) {
592 irg_block_walk_2(pred, pre, post, env);
595 assert(get_irn_opcode(pred) == iro_Bad);
599 if(post) post(node, env);
605 /* walks only over Block nodes in the graph. Has it's own visited
606 flag, so that it can be interleaved with the other walker. */
607 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
609 ir_node *block, *pred;
612 hook_irg_block_walk(current_ir_graph, node, (generic_func *)pre, (generic_func *)post);
615 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
616 * interleaves with irg_walk */
617 set_using_block_visited(current_ir_graph);
618 inc_irg_block_visited(current_ir_graph);
619 block = is_Block(node) ? node : get_nodes_block(node);
620 assert(get_irn_op(block) == op_Block);
621 irg_block_walk_2(block, pre, post, env);
623 /* keepalive: the endless loops ... */
624 if (get_irn_op(node) == op_End) {
625 int arity = get_irn_arity(node);
626 for (i = 0; i < arity; i++) {
627 pred = get_irn_n(node, i);
628 if (get_irn_op(pred) == op_Block)
629 irg_block_walk_2(pred, pre, post, env);
631 /* Sometimes the blocks died, but are still reachable through Phis.
632 * Make sure the algorithms that try to remove these reach them. */
633 for (i = 0; i < arity; i++) {
634 pred = get_irn_n(node, i);
635 if (get_irn_op(pred) == op_Phi) {
636 ir_node *block = get_nodes_block(pred);
639 irg_block_walk_2(block, pre, post, env);
644 clear_using_block_visited(current_ir_graph);
648 * walk over a graph block wise
650 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
651 irg_walk_func *post, void *env) {
652 ir_graph * rem = current_ir_graph;
653 current_ir_graph = irg;
654 irg_block_walk(get_irg_end(irg), pre, post, env);
655 current_ir_graph = rem;
659 * Additionally walk over all anchors. Do NOT increase the visit flag.
661 void irg_walk_anchors(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
663 ir_graph * rem = current_ir_graph;
664 current_ir_graph = irg;
666 for (i = 0; i < anchor_max; ++i) {
667 ir_node *anchor = irg->anchors[i];
669 irg_walk_2(anchor, pre, post, env);
671 current_ir_graph = rem;
674 /********************************************************************/
676 typedef struct walk_env {
683 * Walk to all constant expressions in this entity.
685 static void walk_entity(ir_entity *ent, void *env)
687 walk_env *my_env = (walk_env *)env;
689 if (get_entity_variability(ent) != variability_uninitialized) {
690 if (is_atomic_entity(ent)) {
691 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
694 int i, n_vals = get_compound_ent_n_values(ent);
696 for (i = 0; i < n_vals; i++)
697 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
702 /* Walks over all code in const_code_irg. */
703 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
707 ir_graph *rem = current_ir_graph;
708 current_ir_graph = get_const_code_irg();
709 inc_irg_visited(current_ir_graph);
715 /* Walk all types that can contain constant entities. */
716 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
717 for (i = 0; i < get_irp_n_types(); i++)
718 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
719 for (i = 0; i < get_irp_n_irgs(); i++)
720 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
722 /* Walk constant array bounds. */
723 for (i = 0; i < get_irp_n_types(); i++) {
724 ir_type *tp = get_irp_type(i);
725 if (is_Array_type(tp)) {
726 for (j = 0; j < get_array_n_dimensions(tp); j++) {
727 ir_node *n = get_array_lower_bound(tp, j);
728 if (n) irg_walk(n, pre, post, env);
729 n = get_array_upper_bound(tp, j);
730 if (n) irg_walk(n, pre, post, env);
735 current_ir_graph = rem;