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 * @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 #ifdef INTERPROCEDURAL_VIEW
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);
276 set_using_irn_visited(current_ir_graph);
277 inc_irg_visited(current_ir_graph);
278 nodes_touched = irg_walk_2(node, pre, post, env);
279 clear_using_irn_visited(current_ir_graph);
280 #ifdef INTERPROCEDURAL_VIEW
289 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
290 ir_graph * rem = current_ir_graph;
292 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
293 current_ir_graph = irg;
294 irg_walk(get_irg_end(irg), pre, post, env);
295 irg->estimated_node_count = nodes_touched;
296 current_ir_graph = rem;
299 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
300 Sets current_ir_graph properly for each walk. Conserves current
302 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
306 for (i = 0, n = get_irp_n_irgs(); i < n; i++) {
307 irg = get_irp_irg(i);
308 irg_walk_graph(irg, pre, post, env);
312 /***************************************************************************/
315 * specialized version of irg_walk_in_or_dep_2, called if only pre callback exists
317 * @return number of visited nodes
320 irg_walk_in_or_dep_2_pre(ir_node *node, irg_walk_func *pre, void *env) {
323 ir_graph *irg = current_ir_graph;
325 set_irn_visited(node, irg->visited);
329 if (node->op != op_Block) {
330 ir_node *pred = get_irn_n(node, -1);
331 if (pred->visited < irg->visited)
332 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
334 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
335 ir_node *pred = get_irn_in_or_dep(node, i);
336 if (pred->visited < irg->visited)
337 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
343 * specialized version of irg_walk_in_or_dep_2, called if only post callback exists
345 * @return number of visited nodes
348 irg_walk_in_or_dep_2_post(ir_node *node, irg_walk_func *post, void *env) {
351 ir_graph *irg = current_ir_graph;
353 set_irn_visited(node, irg->visited);
355 if (node->op != op_Block) {
356 ir_node *pred = get_irn_n(node, -1);
357 if (pred->visited < irg->visited)
358 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
360 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
361 ir_node *pred = get_irn_in_or_dep(node, i);
362 if (pred->visited < irg->visited)
363 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
372 * specialized version of irg_walk_in_or_dep_2, called if pre and post callbacks exist
374 * @return number of visited nodes
377 irg_walk_in_or_dep_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env) {
380 ir_graph *irg = current_ir_graph;
382 set_irn_visited(node, irg->visited);
386 if (node->op != op_Block) {
387 ir_node *pred = get_irn_n(node, -1);
388 if (pred->visited < irg->visited)
389 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
391 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
392 ir_node *pred = get_irn_in_or_dep(node, i);
393 if (pred->visited < irg->visited)
394 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
403 * Intraprozedural graph walker. Follows dependency edges as well.
405 * @return number of visited nodes
408 irg_walk_in_or_dep_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
410 if (node->visited < current_ir_graph->visited) {
411 if (! post) return irg_walk_in_or_dep_2_pre (node, pre, env);
412 else if (! pre) return irg_walk_in_or_dep_2_post(node, post, env);
413 else return irg_walk_in_or_dep_2_both(node, pre, post, env);
419 * Generic graph walker. Follows dependency edges as well.
421 void irg_walk_in_or_dep(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
423 assert(is_ir_node(node));
425 if (get_interprocedural_view()) {
426 assert(0 && "This is not yet implemented.");
428 set_using_irn_visited(current_ir_graph);
429 inc_irg_visited(current_ir_graph);
430 nodes_touched = irg_walk_in_or_dep_2(node, pre, post, env);
431 clear_using_irn_visited(current_ir_graph);
437 * Walk over a graph. Follow all edges (including dependencies)
439 void irg_walk_in_or_dep_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
440 ir_graph * rem = current_ir_graph;
442 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
443 current_ir_graph = irg;
444 irg_walk_in_or_dep(get_irg_end(irg), pre, post, env);
445 irg->estimated_node_count = nodes_touched;
446 current_ir_graph = rem;
449 /***************************************************************************/
452 * Returns current_ir_graph and sets it to the irg of predecessor index
455 static INLINE ir_graph *
456 switch_irg(ir_node *n, int index) {
457 ir_graph *old_current = current_ir_graph;
459 if (get_interprocedural_view()) {
460 /* Only Filter and Block nodes can have predecessors in other graphs. */
461 if (get_irn_op(n) == op_Filter)
462 n = get_nodes_block(n);
463 if (get_irn_op(n) == op_Block) {
464 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
465 if (is_ip_cfop(cfop)) {
466 current_ir_graph = get_irn_irg(cfop);
475 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
478 ir_graph *rem = NULL;
481 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
482 set_irn_visited(node, get_irg_visited(current_ir_graph));
484 if (pre) pre(node, env);
486 if (is_no_Block(node))
487 cg_walk_2(get_nodes_block(node), pre, post, env);
488 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
489 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
490 switch to the irg of the predecessor, don't we? */
491 cg_walk_2(get_irn_n(node, i), pre, post, env);
492 current_ir_graph = rem;
495 if (post) post(node, env);
500 #ifdef INTERPROCEDURAL_VIEW
501 /* Walks all irgs in interprocedural view. Visits each node only once. */
502 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
504 ir_graph *rem = current_ir_graph;
505 int rem_view = get_interprocedural_view();
507 set_interprocedural_view(1);
509 inc_max_irg_visited();
510 /* Fix all irg_visited flags */
511 for (i = 0; i < get_irp_n_irgs(); i++)
512 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
514 /* Walk starting at unreachable procedures. Only these
515 * have End blocks visible in interprocedural view. */
516 for (i = 0; i < get_irp_n_irgs(); i++) {
518 current_ir_graph = get_irp_irg(i);
520 sb = get_irg_start_block(current_ir_graph);
522 if ((get_Block_n_cfgpreds(sb) > 1) ||
523 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
525 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
528 /* Check whether we walked all procedures: there could be procedures
529 with cyclic calls but no call from the outside. */
530 for (i = 0; i < get_irp_n_irgs(); i++) {
532 current_ir_graph = get_irp_irg(i);
534 /* Test start block: if inner procedure end and end block are not
535 * visible and therefore not marked. */
536 sb = get_irg_start_block(current_ir_graph);
537 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
538 cg_walk_2(sb, pre, post, env);
542 /* Walk all endless loops in inner procedures.
543 * We recognize an inner procedure if the End node is not visited. */
544 for (i = 0; i < get_irp_n_irgs(); i++) {
546 current_ir_graph = get_irp_irg(i);
547 e = get_irg_end(current_ir_graph);
548 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
550 /* Don't visit the End node. */
551 for (j = 0; j < get_End_n_keepalives(e); j++)
552 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
556 set_interprocedural_view(rem_view);
557 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);
604 /* walks only over Block nodes in the graph. Has it's own visited
605 flag, so that it can be interleaved with the other walker. */
606 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
608 ir_node *block, *pred;
611 hook_irg_block_walk(current_ir_graph, node, (generic_func *)pre, (generic_func *)post);
614 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
615 * interleaves with irg_walk */
616 set_using_block_visited(current_ir_graph);
617 inc_irg_block_visited(current_ir_graph);
618 block = is_Block(node) ? node : get_nodes_block(node);
619 assert(get_irn_op(block) == op_Block);
620 irg_block_walk_2(block, pre, post, env);
622 /* keepalive: the endless loops ... */
623 if (get_irn_op(node) == op_End) {
624 int arity = get_irn_arity(node);
625 for (i = 0; i < arity; i++) {
626 pred = get_irn_n(node, i);
627 if (get_irn_op(pred) == op_Block)
628 irg_block_walk_2(pred, pre, post, env);
630 /* Sometimes the blocks died, but are still reachable through Phis.
631 * Make sure the algorithms that try to remove these reach them. */
632 for (i = 0; i < arity; i++) {
633 pred = get_irn_n(node, i);
634 if (get_irn_op(pred) == op_Phi) {
635 ir_node *block = get_nodes_block(pred);
638 irg_block_walk_2(block, pre, post, env);
643 clear_using_block_visited(current_ir_graph);
647 * walk over a graph block wise
649 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
650 irg_walk_func *post, void *env) {
651 ir_graph * rem = current_ir_graph;
652 current_ir_graph = irg;
653 irg_block_walk(get_irg_end(irg), pre, post, env);
654 current_ir_graph = rem;
658 * Additionally walk over all anchors. Do NOT increase the visit flag.
660 void irg_walk_anchors(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
661 ir_graph * rem = current_ir_graph;
662 current_ir_graph = irg;
664 inc_irg_visited(irg);
665 irg_walk_2(irg->anchor, pre, post, env);
667 current_ir_graph = rem;
670 /********************************************************************/
672 typedef struct walk_env {
679 * Walk to all constant expressions in this entity.
681 static void walk_entity(ir_entity *ent, void *env)
683 walk_env *my_env = (walk_env *)env;
685 if (get_entity_variability(ent) != variability_uninitialized) {
686 if (is_atomic_entity(ent)) {
687 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
689 int i, n_vals = get_compound_ent_n_values(ent);
691 for (i = 0; i < n_vals; i++)
692 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
697 /* Walks over all code in const_code_irg. */
698 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
702 ir_graph *rem = current_ir_graph;
703 current_ir_graph = get_const_code_irg();
704 inc_irg_visited(current_ir_graph);
710 /* Walk all types that can contain constant entities. */
711 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
712 n_types = get_irp_n_types();
713 for (i = 0; i < n_types; i++)
714 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
715 for (i = 0; i < get_irp_n_irgs(); i++)
716 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
718 /* Walk constant array bounds. */
719 for (i = 0; i < n_types; i++) {
720 ir_type *tp = get_irp_type(i);
721 if (is_Array_type(tp)) {
722 int n_dim = get_array_n_dimensions(tp);
723 for (j = 0; j < n_dim; j++) {
724 ir_node *n = get_array_lower_bound(tp, j);
725 if (n) irg_walk(n, pre, post, env);
726 n = get_array_upper_bound(tp, j);
727 if (n) irg_walk(n, pre, post, env);
732 current_ir_graph = rem;