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 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 inc_irg_visited(current_ir_graph);
264 nodes_touched = irg_walk_2(node, pre, post, env);
272 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
273 ir_graph * rem = current_ir_graph;
275 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
276 current_ir_graph = irg;
277 irg_walk(get_irg_end(irg), pre, post, env);
278 irg->estimated_node_count = nodes_touched;
279 current_ir_graph = rem;
282 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
283 Sets current_ir_graph properly for each walk. Conserves current
285 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
289 rem = current_ir_graph;
291 for (i = 0; i < get_irp_n_irgs(); i++) {
292 irg = get_irp_irg(i);
293 current_ir_graph = irg;
294 irg_walk(get_irg_end(irg), pre, post, env);
296 current_ir_graph = rem;
299 /***************************************************************************/
302 * Returns current_ir_graph and sets it to the irg of predecessor index
305 static INLINE ir_graph *
306 switch_irg (ir_node *n, int index) {
307 ir_graph *old_current = current_ir_graph;
309 if (get_interprocedural_view()) {
310 /* Only Filter and Block nodes can have predecessors in other graphs. */
311 if (get_irn_op(n) == op_Filter)
312 n = get_nodes_block(n);
313 if (get_irn_op(n) == op_Block) {
314 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
315 if (is_ip_cfop(cfop)) {
316 current_ir_graph = get_irn_irg(cfop);
325 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
328 ir_graph *rem = NULL;
331 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
332 set_irn_visited(node, get_irg_visited(current_ir_graph));
334 if (pre) pre(node, env);
336 if (is_no_Block(node))
337 cg_walk_2(get_nodes_block(node), pre, post, env);
338 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
339 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
340 switch to the irg of the predecessor, don't we? */
341 cg_walk_2(get_irn_n(node, i), pre, post, env);
342 current_ir_graph = rem;
345 if (post) post(node, env);
351 /* Walks all irgs in interprocedural view. Visits each node only once. */
352 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
354 ir_graph *rem = current_ir_graph;
355 int rem_view = get_interprocedural_view();
357 set_interprocedural_view(1);
359 inc_max_irg_visited();
360 /* Fix all irg_visited flags */
361 for (i = 0; i < get_irp_n_irgs(); i++)
362 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
364 /* Walk starting at unreachable procedures. Only these
365 * have End blocks visible in interprocedural view. */
366 for (i = 0; i < get_irp_n_irgs(); i++) {
368 current_ir_graph = get_irp_irg(i);
370 sb = get_irg_start_block(current_ir_graph);
372 if ((get_Block_n_cfgpreds(sb) > 1) ||
373 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
375 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
378 /* Check whether we walked all procedures: there could be procedures
379 with cyclic calls but no call from the outside. */
380 for (i = 0; i < get_irp_n_irgs(); i++) {
382 current_ir_graph = get_irp_irg(i);
384 /* Test start block: if inner procedure end and end block are not
385 * visible and therefore not marked. */
386 sb = get_irg_start_block(current_ir_graph);
387 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
388 cg_walk_2(sb, pre, post, env);
392 /* Walk all endless loops in inner procedures.
393 * We recognize an inner procedure if the End node is not visited. */
394 for (i = 0; i < get_irp_n_irgs(); i++) {
396 current_ir_graph = get_irp_irg(i);
397 e = get_irg_end(current_ir_graph);
398 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
400 /* Don't visit the End node. */
401 for (j = 0; j < get_End_n_keepalives(e); j++)
402 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
406 set_interprocedural_view(rem_view);
407 current_ir_graph = rem;
411 /***************************************************************************/
413 /* Walks back from n until it finds a real cf op. */
414 static ir_node *get_cf_op(ir_node *n) {
420 if (!(is_cfop(pred) || is_fragile_op(pred) ||
421 (get_irn_op(pred) == op_Bad)))
427 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
431 if (Block_not_block_visited(node)) {
432 mark_Block_block_visited(node);
434 if(pre) pre(node, env);
436 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
437 /* find the corresponding predecessor block. */
438 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
439 pred = get_nodes_block(pred);
440 if(get_irn_opcode(pred) == iro_Block) {
442 irg_block_walk_2(pred, pre, post, env);
445 assert(get_irn_opcode(pred) == iro_Bad);
449 if(post) post(node, env);
455 /* walks only over Block nodes in the graph. Has it's own visited
456 flag, so that it can be interleaved with the other walker. */
457 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
459 ir_node *block, *pred;
462 hook_irg_block_walk(current_ir_graph, node, (generic_func *)pre, (generic_func *)post);
465 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
466 * interleaves with irg_walk */
467 inc_irg_block_visited(current_ir_graph);
468 if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
469 assert(get_irn_op(block) == op_Block);
470 irg_block_walk_2(block, pre, post, env);
472 /* keepalive: the endless loops ... */
473 if (get_irn_op(node) == op_End) {
474 int arity = get_irn_arity(node);
475 for (i = 0; i < arity; i++) {
476 pred = get_irn_n(node, i);
477 if (get_irn_op(pred) == op_Block)
478 irg_block_walk_2(pred, pre, post, env);
480 /* Sometimes the blocks died, but are still reachable through Phis.
481 * Make sure the algorithms that try to remove these reach them. */
482 for (i = 0; i < arity; i++) {
483 pred = get_irn_n(node, i);
484 if (get_irn_op(pred) == op_Phi) {
485 ir_node *block = get_nodes_block(pred);
488 irg_block_walk_2(block, pre, post, env);
497 * walk over a graph block wise
499 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
500 irg_walk_func *post, void *env) {
501 ir_graph * rem = current_ir_graph;
502 current_ir_graph = irg;
503 irg_block_walk(get_irg_end(irg), pre, post, env);
504 current_ir_graph = rem;
508 * Additionally walk over all anchors. Do NOT increase the visit flag.
510 void irg_walk_anchors(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
512 ir_graph * rem = current_ir_graph;
513 current_ir_graph = irg;
515 for (i = 0; i < anchor_max; ++i) {
516 ir_node *anchor = irg->anchors[i];
518 irg_walk_2(anchor, pre, post, env);
520 current_ir_graph = rem;
523 /********************************************************************/
525 typedef struct walk_env {
532 * Walk to all constant expressions in this entity.
534 static void walk_entity(entity *ent, void *env)
536 walk_env *my_env = (walk_env *)env;
538 if (get_entity_variability(ent) != variability_uninitialized) {
539 if (is_atomic_entity(ent)) {
540 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
543 int i, n_vals = get_compound_ent_n_values(ent);
545 for (i = 0; i < n_vals; i++)
546 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
551 /* Walks over all code in const_code_irg. */
552 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
556 ir_graph *rem = current_ir_graph;
557 current_ir_graph = get_const_code_irg();
558 inc_irg_visited(current_ir_graph);
564 /* Walk all types that can contain constant entities. */
565 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
566 for (i = 0; i < get_irp_n_types(); i++)
567 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
568 for (i = 0; i < get_irp_n_irgs(); i++)
569 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
571 /* Walk constant array bounds. */
572 for (i = 0; i < get_irp_n_types(); i++) {
573 ir_type *tp = get_irp_type(i);
574 if (is_Array_type(tp)) {
575 for (j = 0; j < get_array_n_dimensions(tp); j++) {
576 ir_node *n = get_array_lower_bound(tp, j);
577 if (n) irg_walk(n, pre, post, env);
578 n = get_array_upper_bound(tp, j);
579 if (n) irg_walk(n, pre, post, env);
584 current_ir_graph = rem;