3 * File name: ir/ir/irgwalk.c
5 * Author: Boris Boesler
6 * Modified by: Goetz Lindenmaier, Michael Beck
9 * Copyright: (c) 1999-20036Universität Karlsruhe
10 * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
16 * traverse an ir graph
17 * - execute the pre function before recursion
18 * - execute the post function after recursion
31 #include "irgraph_t.h" /* visited flag */
42 * Walk over an interprocedural graph (callgraph).
43 * Visits only graphs in irg_set.
45 static void irg_walk_cg(ir_node * node, unsigned long visited, eset * irg_set,
46 irg_walk_func *pre, irg_walk_func *post, void * env) {
48 ir_graph * rem = current_ir_graph;
51 assert(node && node->kind == k_ir_node);
52 if (get_irn_visited(node) >= visited) return;
54 set_irn_visited(node, visited);
56 if (pre) pre(node, env);
58 pred = skip_Proj(node);
59 if (get_irn_op(pred) == op_CallBegin
60 || get_irn_op(pred) == op_EndReg
61 || get_irn_op(pred) == op_EndExcept) {
62 current_ir_graph = get_irn_irg(pred);
65 if (is_no_Block(node)) { /* not block */
66 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
69 if (get_irn_op(node) == op_Block) { /* block */
70 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
71 ir_node * exec = get_irn_n(node, i);
72 ir_node * pred = skip_Proj(exec);
73 if ((get_irn_op(pred) != op_CallBegin
74 && get_irn_op(pred) != op_EndReg
75 && get_irn_op(pred) != op_EndExcept)
76 || eset_contains(irg_set, get_irn_irg(pred))) {
77 irg_walk_cg(exec, visited, irg_set, pre, post, env);
80 } else if (get_irn_op(node) == op_Filter) { /* filter */
81 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
82 ir_node * pred = get_irn_n(node, i);
83 if (get_irn_op(pred) == op_Unknown || get_irn_op(pred) == op_Bad) {
84 irg_walk_cg(pred, visited, irg_set, pre, post, env);
87 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
89 if (op_Bad == get_irn_op (exec)) {
93 assert(get_irn_op(exec) == op_CallBegin
94 || get_irn_op(exec) == op_EndReg
95 || get_irn_op(exec) == op_EndExcept);
96 if (eset_contains(irg_set, get_irn_irg(exec))) {
97 current_ir_graph = get_irn_irg(exec);
98 irg_walk_cg(pred, visited, irg_set, pre, post, env);
99 current_ir_graph = rem;
103 } else { /* everything else */
104 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
105 irg_walk_cg(get_irn_n(node, i), visited, irg_set, pre, post, env);
109 if (post) post(node, env);
111 current_ir_graph = rem;
116 * Insert all ir_graphs in irg_set, that are (transitive) reachable.
118 static void collect_irgs(ir_node * node, eset * irg_set) {
121 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
122 ir_entity * ent = get_Call_callee(node, i);
123 ir_graph * irg = get_entity_irg(ent);
124 if (irg && !eset_contains(irg_set, irg)) {
125 eset_insert(irg_set, irg);
126 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
133 * specialized version of irg_walk_2, called if only pre callback exists
135 * @return number of visited nodes
138 irg_walk_2_pre(ir_node *node, irg_walk_func *pre, void * env) {
141 ir_graph *irg = current_ir_graph;
143 set_irn_visited(node, irg->visited);
147 if (node->op != op_Block) {
148 ir_node *pred = get_irn_n(node, -1);
149 if (pred->visited < irg->visited)
150 cnt += irg_walk_2_pre(pred, pre, env);
152 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
153 ir_node *pred = get_irn_n(node, i);
154 if (pred->visited < irg->visited)
155 cnt += irg_walk_2_pre(pred, pre, env);
161 * specialized version of irg_walk_2, called if only post callback exists
163 * @return number of visited nodes
166 irg_walk_2_post(ir_node *node, irg_walk_func *post, void * env) {
169 ir_graph *irg = current_ir_graph;
171 set_irn_visited(node, irg->visited);
173 if (node->op != op_Block) {
174 ir_node *pred = get_irn_n(node, -1);
175 if (pred->visited < irg->visited)
176 cnt += irg_walk_2_post(pred, post, env);
178 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
179 ir_node *pred = get_irn_n(node, i);
180 if (pred->visited < irg->visited)
181 cnt += irg_walk_2_post(pred, post, env);
190 * specialized version of irg_walk_2, called if pre and post callbacks exist
192 * @return number of visited nodes
195 irg_walk_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env) {
198 ir_graph *irg = current_ir_graph;
200 set_irn_visited(node, irg->visited);
204 if (node->op != op_Block) {
205 ir_node *pred = get_irn_n(node, -1);
206 if (pred->visited < irg->visited)
207 cnt += irg_walk_2_both(pred, pre, post, env);
209 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
210 ir_node *pred = get_irn_n(node, i);
211 if (pred->visited < irg->visited)
212 cnt += irg_walk_2_both(pred, pre, post, env);
221 * Intraprozedural graph walker.
223 * @return number of visited nodes
226 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
228 if (node->visited < current_ir_graph->visited) {
229 if (!post) return irg_walk_2_pre (node, pre, env);
230 else if (!pre) return irg_walk_2_post(node, post, env);
231 else return irg_walk_2_both(node, pre, post, env);
237 static unsigned nodes_touched = 0;
240 * generic graph walker
242 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
244 assert(is_ir_node(node));
246 if (get_interprocedural_view()) {
247 eset * irg_set = eset_create();
248 unsigned long visited;
250 assert(get_irp_ip_view_state() == ip_view_valid);
252 set_interprocedural_view(0);
253 eset_insert(irg_set, current_ir_graph);
254 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
255 set_interprocedural_view(1);
256 visited = get_max_irg_visited() + 1;
257 for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
258 set_irg_visited(irg, visited);
260 irg_walk_cg(node, visited, irg_set, pre, post, env);
261 eset_destroy(irg_set);
263 assert(! inside_irg_walk(current_ir_graph)); /* we must not already be inside an irg walk */
264 set_inside_irg_walk(current_ir_graph);
265 inc_irg_visited(current_ir_graph);
266 nodes_touched = irg_walk_2(node, pre, post, env);
267 clear_inside_irg_walk(current_ir_graph);
275 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
276 ir_graph * rem = current_ir_graph;
278 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
279 current_ir_graph = irg;
280 irg_walk(get_irg_end(irg), pre, post, env);
281 irg->estimated_node_count = nodes_touched;
282 current_ir_graph = rem;
285 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
286 Sets current_ir_graph properly for each walk. Conserves current
288 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
292 rem = current_ir_graph;
294 for (i = 0; i < get_irp_n_irgs(); i++) {
295 irg = get_irp_irg(i);
296 current_ir_graph = irg;
297 irg_walk(get_irg_end(irg), pre, post, env);
299 current_ir_graph = rem;
302 /***************************************************************************/
305 * specialized version of irg_walk_in_or_dep_2, called if only pre callback exists
307 * @return number of visited nodes
310 irg_walk_in_or_dep_2_pre(ir_node *node, irg_walk_func *pre, void *env) {
313 ir_graph *irg = current_ir_graph;
315 set_irn_visited(node, irg->visited);
319 if (node->op != op_Block) {
320 ir_node *pred = get_irn_n(node, -1);
321 if (pred->visited < irg->visited)
322 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
324 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
325 ir_node *pred = get_irn_in_or_dep(node, i);
326 if (pred->visited < irg->visited)
327 cnt += irg_walk_in_or_dep_2_pre(pred, pre, env);
333 * specialized version of irg_walk_in_or_dep_2, called if only post callback exists
335 * @return number of visited nodes
338 irg_walk_in_or_dep_2_post(ir_node *node, irg_walk_func *post, void *env) {
341 ir_graph *irg = current_ir_graph;
343 set_irn_visited(node, irg->visited);
345 if (node->op != op_Block) {
346 ir_node *pred = get_irn_n(node, -1);
347 if (pred->visited < irg->visited)
348 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
350 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
351 ir_node *pred = get_irn_in_or_dep(node, i);
352 if (pred->visited < irg->visited)
353 cnt += irg_walk_in_or_dep_2_post(pred, post, env);
362 * specialized version of irg_walk_in_or_dep_2, called if pre and post callbacks exist
364 * @return number of visited nodes
367 irg_walk_in_or_dep_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env) {
370 ir_graph *irg = current_ir_graph;
372 set_irn_visited(node, irg->visited);
376 if (node->op != op_Block) {
377 ir_node *pred = get_irn_n(node, -1);
378 if (pred->visited < irg->visited)
379 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
381 for (i = get_irn_ins_or_deps(node) - 1; i >= 0; --i) {
382 ir_node *pred = get_irn_in_or_dep(node, i);
383 if (pred->visited < irg->visited)
384 cnt += irg_walk_in_or_dep_2_both(pred, pre, post, env);
393 * Intraprozedural graph walker. Follows dependency edges as well.
395 * @return number of visited nodes
398 irg_walk_in_or_dep_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
400 if (node->visited < current_ir_graph->visited) {
401 if (! post) return irg_walk_in_or_dep_2_pre (node, pre, env);
402 else if (! pre) return irg_walk_in_or_dep_2_post(node, post, env);
403 else return irg_walk_in_or_dep_2_both(node, pre, post, env);
409 * Generic graph walker. Follows dependency edges as well.
411 void irg_walk_in_or_dep(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
413 assert(is_ir_node(node));
415 if (get_interprocedural_view()) {
416 assert(0 && "This is not yet implemented.");
418 assert(! inside_irg_walk(current_ir_graph)); /* we must not already be inside an irg walk */
419 set_inside_irg_walk(current_ir_graph);
420 inc_irg_visited(current_ir_graph);
421 nodes_touched = irg_walk_in_or_dep_2(node, pre, post, env);
422 clear_inside_irg_walk(current_ir_graph);
428 * Walk over a graph. Follow all edges (including dependencies)
430 void irg_walk_in_or_dep_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
431 ir_graph * rem = current_ir_graph;
433 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
434 current_ir_graph = irg;
435 irg_walk_in_or_dep(get_irg_end(irg), pre, post, env);
436 irg->estimated_node_count = nodes_touched;
437 current_ir_graph = rem;
440 /***************************************************************************/
443 * Returns current_ir_graph and sets it to the irg of predecessor index
446 static INLINE ir_graph *
447 switch_irg (ir_node *n, int index) {
448 ir_graph *old_current = current_ir_graph;
450 if (get_interprocedural_view()) {
451 /* Only Filter and Block nodes can have predecessors in other graphs. */
452 if (get_irn_op(n) == op_Filter)
453 n = get_nodes_block(n);
454 if (get_irn_op(n) == op_Block) {
455 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
456 if (is_ip_cfop(cfop)) {
457 current_ir_graph = get_irn_irg(cfop);
466 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
469 ir_graph *rem = NULL;
472 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
473 set_irn_visited(node, get_irg_visited(current_ir_graph));
475 if (pre) pre(node, env);
477 if (is_no_Block(node))
478 cg_walk_2(get_nodes_block(node), pre, post, env);
479 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
480 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
481 switch to the irg of the predecessor, don't we? */
482 cg_walk_2(get_irn_n(node, i), pre, post, env);
483 current_ir_graph = rem;
486 if (post) post(node, env);
492 /* Walks all irgs in interprocedural view. Visits each node only once. */
493 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
495 ir_graph *rem = current_ir_graph;
496 int rem_view = get_interprocedural_view();
498 set_interprocedural_view(1);
500 inc_max_irg_visited();
501 /* Fix all irg_visited flags */
502 for (i = 0; i < get_irp_n_irgs(); i++)
503 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
505 /* Walk starting at unreachable procedures. Only these
506 * have End blocks visible in interprocedural view. */
507 for (i = 0; i < get_irp_n_irgs(); i++) {
509 current_ir_graph = get_irp_irg(i);
511 sb = get_irg_start_block(current_ir_graph);
513 if ((get_Block_n_cfgpreds(sb) > 1) ||
514 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
516 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
519 /* Check whether we walked all procedures: there could be procedures
520 with cyclic calls but no call from the outside. */
521 for (i = 0; i < get_irp_n_irgs(); i++) {
523 current_ir_graph = get_irp_irg(i);
525 /* Test start block: if inner procedure end and end block are not
526 * visible and therefore not marked. */
527 sb = get_irg_start_block(current_ir_graph);
528 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
529 cg_walk_2(sb, pre, post, env);
533 /* Walk all endless loops in inner procedures.
534 * We recognize an inner procedure if the End node is not visited. */
535 for (i = 0; i < get_irp_n_irgs(); i++) {
537 current_ir_graph = get_irp_irg(i);
538 e = get_irg_end(current_ir_graph);
539 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
541 /* Don't visit the End node. */
542 for (j = 0; j < get_End_n_keepalives(e); j++)
543 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
547 set_interprocedural_view(rem_view);
548 current_ir_graph = rem;
552 /***************************************************************************/
554 /* Walks back from n until it finds a real cf op. */
555 static ir_node *get_cf_op(ir_node *n) {
561 if (!(is_cfop(pred) || is_fragile_op(pred) || is_Bad(pred)))
567 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
571 if (Block_not_block_visited(node)) {
572 mark_Block_block_visited(node);
574 if(pre) pre(node, env);
576 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
577 /* find the corresponding predecessor block. */
578 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
579 pred = get_nodes_block(pred);
580 if(get_irn_opcode(pred) == iro_Block) {
582 irg_block_walk_2(pred, pre, post, env);
585 assert(get_irn_opcode(pred) == iro_Bad);
589 if(post) post(node, env);
595 /* walks only over Block nodes in the graph. Has it's own visited
596 flag, so that it can be interleaved with the other walker. */
597 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
599 ir_node *block, *pred;
602 hook_irg_block_walk(current_ir_graph, node, (generic_func *)pre, (generic_func *)post);
605 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
606 * interleaves with irg_walk */
607 assert(! inside_irg_walk(current_ir_graph)); /* we must not already be in a block walk */
608 inc_irg_block_visited(current_ir_graph);
609 set_inside_block_walk(current_ir_graph);
610 block = is_Block(node) ? node : get_nodes_block(node);
611 assert(get_irn_op(block) == op_Block);
612 irg_block_walk_2(block, pre, post, env);
614 /* keepalive: the endless loops ... */
615 if (get_irn_op(node) == op_End) {
616 int arity = get_irn_arity(node);
617 for (i = 0; i < arity; i++) {
618 pred = get_irn_n(node, i);
619 if (get_irn_op(pred) == op_Block)
620 irg_block_walk_2(pred, pre, post, env);
622 /* Sometimes the blocks died, but are still reachable through Phis.
623 * Make sure the algorithms that try to remove these reach them. */
624 for (i = 0; i < arity; i++) {
625 pred = get_irn_n(node, i);
626 if (get_irn_op(pred) == op_Phi) {
627 ir_node *block = get_nodes_block(pred);
630 irg_block_walk_2(block, pre, post, env);
635 clear_inside_block_walk(current_ir_graph);
640 * walk over a graph block wise
642 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
643 irg_walk_func *post, void *env) {
644 ir_graph * rem = current_ir_graph;
645 current_ir_graph = irg;
646 irg_block_walk(get_irg_end(irg), pre, post, env);
647 current_ir_graph = rem;
651 * Additionally walk over all anchors. Do NOT increase the visit flag.
653 void irg_walk_anchors(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
655 ir_graph * rem = current_ir_graph;
656 current_ir_graph = irg;
658 for (i = 0; i < anchor_max; ++i) {
659 ir_node *anchor = irg->anchors[i];
661 irg_walk_2(anchor, pre, post, env);
663 current_ir_graph = rem;
666 /********************************************************************/
668 typedef struct walk_env {
675 * Walk to all constant expressions in this entity.
677 static void walk_entity(ir_entity *ent, void *env)
679 walk_env *my_env = (walk_env *)env;
681 if (get_entity_variability(ent) != variability_uninitialized) {
682 if (is_atomic_entity(ent)) {
683 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
686 int i, n_vals = get_compound_ent_n_values(ent);
688 for (i = 0; i < n_vals; i++)
689 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
694 /* Walks over all code in const_code_irg. */
695 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
699 ir_graph *rem = current_ir_graph;
700 current_ir_graph = get_const_code_irg();
701 inc_irg_visited(current_ir_graph);
707 /* Walk all types that can contain constant entities. */
708 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
709 for (i = 0; i < get_irp_n_types(); i++)
710 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
711 for (i = 0; i < get_irp_n_irgs(); i++)
712 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
714 /* Walk constant array bounds. */
715 for (i = 0; i < get_irp_n_types(); i++) {
716 ir_type *tp = get_irp_type(i);
717 if (is_Array_type(tp)) {
718 for (j = 0; j < get_array_n_dimensions(tp); 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;