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"
51 * Walk over an interprocedural graph (callgraph).
52 * Visits only graphs in irg_set.
54 static void irg_walk_cg(ir_node * node, ir_visited_t visited,
55 pset_new_t *irg_set, irg_walk_func *pre,
56 irg_walk_func *post, void * env) {
58 ir_graph * rem = current_ir_graph;
61 assert(node && node->kind == k_ir_node);
62 if (get_irn_visited(node) >= visited) return;
64 set_irn_visited(node, visited);
66 if (pre) pre(node, env);
68 pred = skip_Proj(node);
69 if (is_CallBegin(pred) ||
70 get_irn_op(pred) == op_EndReg ||
71 get_irn_op(pred) == op_EndExcept) {
72 current_ir_graph = get_irn_irg(pred);
75 if (is_no_Block(node)) { /* not block */
76 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
79 if (is_Block(node)) { /* block */
80 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
81 ir_node * exec = get_irn_n(node, i);
82 ir_node * pred = skip_Proj(exec);
84 !is_CallBegin(pred) &&
85 get_irn_op(pred) != op_EndReg &&
86 get_irn_op(pred) != op_EndExcept
87 ) || pset_new_contains(irg_set, get_irn_irg(pred))) {
88 irg_walk_cg(exec, visited, irg_set, pre, post, env);
91 } else if (is_Filter(node)) { /* filter */
92 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
93 ir_node * pred = get_irn_n(node, i);
94 if (is_Unknown(pred) || is_Bad(pred)) {
95 irg_walk_cg(pred, visited, irg_set, pre, post, env);
98 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
104 assert(is_CallBegin(exec) ||
105 get_irn_op(exec) == op_EndReg ||
106 get_irn_op(exec) == op_EndExcept);
107 if (pset_new_contains(irg_set, get_irn_irg(exec))) {
108 current_ir_graph = get_irn_irg(exec);
109 irg_walk_cg(pred, visited, irg_set, pre, post, env);
110 current_ir_graph = rem;
114 } else { /* everything else */
115 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
116 irg_walk_cg(get_irn_n(node, i), visited, irg_set, pre, post, env);
120 if (post) post(node, env);
122 current_ir_graph = rem;
127 * Insert all ir_graphs in irg_set, that are (transitive) reachable.
129 static void collect_irgs(ir_node * node, pset_new_t *irg_set) {
132 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
133 ir_entity * ent = get_Call_callee(node, i);
134 ir_graph * irg = get_entity_irg(ent);
135 if (irg && !pset_new_contains(irg_set, irg)) {
136 pset_new_insert(irg_set, irg);
137 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
144 * specialized version of irg_walk_2, called if only pre callback exists
146 * @return number of visited nodes
149 irg_walk_2_pre(ir_node *node, irg_walk_func *pre, void * env) {
152 ir_graph *irg = current_ir_graph;
154 set_irn_visited(node, irg->visited);
158 if (node->op != op_Block) {
159 ir_node *pred = get_irn_n(node, -1);
160 if (pred->visited < irg->visited)
161 cnt += irg_walk_2_pre(pred, pre, env);
163 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
164 ir_node *pred = get_irn_n(node, i);
165 if (pred->visited < irg->visited)
166 cnt += irg_walk_2_pre(pred, pre, env);
172 * specialized version of irg_walk_2, called if only post callback exists
174 * @return number of visited nodes
177 irg_walk_2_post(ir_node *node, irg_walk_func *post, void * env) {
180 ir_graph *irg = current_ir_graph;
182 set_irn_visited(node, irg->visited);
184 if (node->op != op_Block) {
185 ir_node *pred = get_irn_n(node, -1);
186 if (pred->visited < irg->visited)
187 cnt += irg_walk_2_post(pred, post, env);
189 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
190 ir_node *pred = get_irn_n(node, i);
191 if (pred->visited < irg->visited)
192 cnt += irg_walk_2_post(pred, post, env);
201 * specialized version of irg_walk_2, called if pre and post callbacks exist
203 * @return number of visited nodes
206 irg_walk_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env) {
209 ir_graph *irg = current_ir_graph;
211 set_irn_visited(node, irg->visited);
215 if (node->op != op_Block) {
216 ir_node *pred = get_irn_n(node, -1);
217 if (pred->visited < irg->visited)
218 cnt += irg_walk_2_both(pred, pre, post, env);
220 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
221 ir_node *pred = get_irn_n(node, i);
222 if (pred->visited < irg->visited)
223 cnt += irg_walk_2_both(pred, pre, post, env);
232 * Intraprozedural graph walker.
234 * @return number of visited nodes
237 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
239 if (node->visited < current_ir_graph->visited) {
240 if (!post) return irg_walk_2_pre (node, pre, env);
241 else if (!pre) return irg_walk_2_post(node, post, env);
242 else return irg_walk_2_both(node, pre, post, env);
248 static unsigned nodes_touched = 0;
251 * generic graph walker
253 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
255 assert(is_ir_node(node));
257 #ifdef INTERPROCEDURAL_VIEW
258 if (get_interprocedural_view()) {
260 pset_new_iterator_t iter;
261 ir_visited_t visited;
263 assert(get_irp_ip_view_state() == ip_view_valid);
265 pset_new_init(&irg_set);
266 set_interprocedural_view(0);
267 pset_new_insert(&irg_set, current_ir_graph);
268 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, &irg_set);
269 set_interprocedural_view(1);
270 visited = get_max_irg_visited() + 1;
272 foreach_pset_new(&irg_set, irg, iter) {
273 set_irg_visited(irg, visited);
275 irg_walk_cg(node, visited, &irg_set, pre, post, env);
276 pset_new_destroy(&irg_set);
279 ir_reserve_resources(current_ir_graph, IR_RESOURCE_IRN_VISITED);
280 inc_irg_visited(current_ir_graph);
281 nodes_touched = irg_walk_2(node, pre, post, env);
282 ir_free_resources(current_ir_graph, IR_RESOURCE_IRN_VISITED);
283 #ifdef INTERPROCEDURAL_VIEW
291 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
292 ir_graph * rem = current_ir_graph;
294 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
295 current_ir_graph = irg;
296 irg_walk(get_irg_end(irg), pre, post, env);
297 irg->estimated_node_count = nodes_touched;
298 current_ir_graph = rem;
301 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
302 Sets current_ir_graph properly for each walk. Conserves current
304 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
308 for (i = 0, n = get_irp_n_irgs(); i < n; i++) {
309 irg = get_irp_irg(i);
310 irg_walk_graph(irg, pre, post, env);
314 /***************************************************************************/
317 * specialized version of irg_walk_in_or_dep_2, called if only pre callback exists
319 * @return number of visited nodes
322 irg_walk_in_or_dep_2_pre(ir_node *node, irg_walk_func *pre, void *env) {
325 ir_graph *irg = current_ir_graph;
327 set_irn_visited(node, irg->visited);
331 if (node->op != op_Block) {
332 ir_node *pred = get_irn_n(node, -1);
333 if (pred->visited < irg->visited)
334 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
336 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
337 ir_node *pred = get_irn_in_or_dep(node, i);
338 if (pred->visited < irg->visited)
339 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
345 * specialized version of irg_walk_in_or_dep_2, called if only post callback exists
347 * @return number of visited nodes
350 irg_walk_in_or_dep_2_post(ir_node *node, irg_walk_func *post, void *env) {
353 ir_graph *irg = current_ir_graph;
355 set_irn_visited(node, irg->visited);
357 if (node->op != op_Block) {
358 ir_node *pred = get_irn_n(node, -1);
359 if (pred->visited < irg->visited)
360 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
362 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
363 ir_node *pred = get_irn_in_or_dep(node, i);
364 if (pred->visited < irg->visited)
365 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
374 * specialized version of irg_walk_in_or_dep_2, called if pre and post callbacks exist
376 * @return number of visited nodes
379 irg_walk_in_or_dep_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env) {
382 ir_graph *irg = current_ir_graph;
384 set_irn_visited(node, irg->visited);
388 if (node->op != op_Block) {
389 ir_node *pred = get_irn_n(node, -1);
390 if (pred->visited < irg->visited)
391 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
393 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
394 ir_node *pred = get_irn_in_or_dep(node, i);
395 if (pred->visited < irg->visited)
396 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
405 * Intraprozedural graph walker. Follows dependency edges as well.
407 * @return number of visited nodes
410 irg_walk_in_or_dep_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
412 if (node->visited < current_ir_graph->visited) {
413 if (! post) return irg_walk_in_or_dep_2_pre (node, pre, env);
414 else if (! pre) return irg_walk_in_or_dep_2_post(node, post, env);
415 else return irg_walk_in_or_dep_2_both(node, pre, post, env);
421 * Generic graph walker. Follows dependency edges as well.
423 void irg_walk_in_or_dep(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
425 assert(is_ir_node(node));
427 if (get_interprocedural_view()) {
428 assert(0 && "This is not yet implemented.");
430 ir_reserve_resources(current_ir_graph, IR_RESOURCE_IRN_VISITED);
431 inc_irg_visited(current_ir_graph);
432 nodes_touched = irg_walk_in_or_dep_2(node, pre, post, env);
433 ir_free_resources(current_ir_graph, IR_RESOURCE_IRN_VISITED);
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. */
463 n = get_nodes_block(n);
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);
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) {
566 while (!is_cfop(n) && !is_fragile_op(n) && !is_Bad(n)) {
574 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
578 if (!Block_block_visited(node)) {
579 mark_Block_block_visited(node);
581 if(pre) pre(node, env);
583 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
584 /* find the corresponding predecessor block. */
585 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
586 pred = get_nodes_block(pred);
587 if(get_irn_opcode(pred) == iro_Block) {
589 irg_block_walk_2(pred, pre, post, env);
592 assert(get_irn_opcode(pred) == iro_Bad);
596 if(post) post(node, env);
601 /* walks only over Block nodes in the graph. Has it's own visited
602 flag, so that it can be interleaved with the other walker. */
603 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
605 ir_graph *irg = current_ir_graph;
606 ir_node *block, *pred;
609 hook_irg_block_walk(irg, node, (generic_func *)pre, (generic_func *)post);
612 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
613 * interleaves with irg_walk */
614 ir_reserve_resources(irg, IR_RESOURCE_BLOCK_VISITED);
615 inc_irg_block_visited(irg);
616 block = is_Block(node) ? node : get_nodes_block(node);
617 assert(is_Block(block));
618 irg_block_walk_2(block, pre, post, env);
620 /* keepalive: the endless loops ... */
622 int arity = get_irn_arity(node);
623 for (i = 0; i < arity; i++) {
624 pred = get_irn_n(node, i);
626 irg_block_walk_2(pred, pre, post, env);
628 /* Sometimes the blocks died, but are still reachable through Phis.
629 * Make sure the algorithms that try to remove these reach them. */
630 for (i = 0; i < arity; i++) {
631 pred = get_irn_n(node, i);
632 if (get_irn_op(pred) == op_Phi) {
633 ir_node *block = get_nodes_block(pred);
636 irg_block_walk_2(block, pre, post, env);
641 ir_free_resources(irg, IR_RESOURCE_BLOCK_VISITED);
645 * walk over a graph block wise
647 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
648 irg_walk_func *post, void *env) {
649 ir_graph * rem = current_ir_graph;
650 current_ir_graph = irg;
651 irg_block_walk(get_irg_end(irg), pre, post, env);
652 current_ir_graph = rem;
656 * Additionally walk over all anchors. Do NOT increase the visit flag.
658 void irg_walk_anchors(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
659 ir_graph * rem = current_ir_graph;
660 current_ir_graph = irg;
662 inc_irg_visited(irg);
663 irg_walk_2(irg->anchor, pre, post, env);
665 current_ir_graph = rem;
668 /********************************************************************/
670 typedef struct walk_env {
676 static void walk_initializer(ir_initializer_t *initializer, walk_env *env)
678 switch(initializer->kind) {
679 case IR_INITIALIZER_CONST:
680 irg_walk(initializer->consti.value, env->pre, env->post, env->env);
682 case IR_INITIALIZER_TARVAL:
683 case IR_INITIALIZER_NULL:
686 case IR_INITIALIZER_COMPOUND: {
688 for(i = 0; i < initializer->compound.n_initializers; ++i) {
689 ir_initializer_t *subinitializer
690 = initializer->compound.initializers[i];
691 walk_initializer(subinitializer, env);
696 panic("invalid initializer found");
700 * Walk to all constant expressions in this entity.
702 static void walk_entity(ir_entity *ent, void *env)
704 walk_env *my_env = (walk_env *)env;
706 if (get_entity_variability(ent) != variability_uninitialized) {
707 if (ent->has_initializer) {
708 walk_initializer(ent->attr.initializer, my_env);
709 } else if (is_atomic_entity(ent)) {
710 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
712 int i, n_vals = get_compound_ent_n_values(ent);
714 for (i = 0; i < n_vals; i++)
715 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
720 /* Walks over all code in const_code_irg. */
721 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
725 ir_graph *rem = current_ir_graph;
726 current_ir_graph = get_const_code_irg();
727 inc_irg_visited(current_ir_graph);
733 /* Walk all types that can contain constant entities. */
734 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
735 n_types = get_irp_n_types();
736 for (i = 0; i < n_types; i++)
737 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
738 for (i = 0; i < get_irp_n_irgs(); i++)
739 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
741 /* Walk constant array bounds. */
742 for (i = 0; i < n_types; i++) {
743 ir_type *tp = get_irp_type(i);
744 if (is_Array_type(tp)) {
745 int n_dim = get_array_n_dimensions(tp);
746 for (j = 0; j < n_dim; j++) {
747 ir_node *n = get_array_lower_bound(tp, j);
748 if (n) irg_walk(n, pre, post, env);
749 n = get_array_upper_bound(tp, j);
750 if (n) irg_walk(n, pre, post, env);
755 current_ir_graph = rem;