3 * File name: ir/ir/irgwalk.c
5 * Author: Boris Boesler
6 * Modified by: Goetz Lindenmaier
9 * Copyright: (c) 1999-2003 Universität 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) {
119 if (get_irn_op(node) == op_Call) {
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) {
142 set_irn_visited(node, current_ir_graph->visited);
146 if (node->op != op_Block) {
147 ir_node *pred = get_irn_n(node, -1);
148 if (pred->visited < current_ir_graph->visited)
149 cnt += irg_walk_2_pre(pred, pre, env);
151 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
152 ir_node *pred = get_irn_n(node, i);
153 if (pred->visited < current_ir_graph->visited)
154 cnt += irg_walk_2_pre(pred, pre, env);
160 * specialized version of irg_walk_2, called if only post callback exists
162 * @return number of visited nodes
165 irg_walk_2_post(ir_node *node, irg_walk_func *post, void * env) {
169 set_irn_visited(node, current_ir_graph->visited);
171 if (node->op != op_Block) {
172 ir_node *pred = get_irn_n(node, -1);
173 if (pred->visited < current_ir_graph->visited)
174 cnt += irg_walk_2_post(pred, post, env);
176 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
177 ir_node *pred = get_irn_n(node, i);
178 if (pred->visited < current_ir_graph->visited)
179 cnt += irg_walk_2_post(pred, post, env);
188 * specialized version of irg_walk_2, called if pre and post callbacks exist
190 * @return number of visited nodes
193 irg_walk_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env) {
197 set_irn_visited(node, current_ir_graph->visited);
201 if (node->op != op_Block) {
202 ir_node *pred = get_irn_n(node, -1);
203 if (pred->visited < current_ir_graph->visited)
204 cnt += irg_walk_2_both(pred, pre, post, env);
206 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
207 ir_node *pred = get_irn_n(node, i);
208 if (pred->visited < current_ir_graph->visited)
209 cnt += irg_walk_2_both(pred, pre, post, env);
218 * Intraprozedural graph walker.
220 * @return number of visited nodes
223 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
225 if (node->visited < current_ir_graph->visited) {
226 if (!post) return irg_walk_2_pre (node, pre, env);
227 else if (!pre) return irg_walk_2_post(node, post, env);
228 else return irg_walk_2_both(node, pre, post, env);
234 static unsigned nodes_touched = 0;
237 * generic graph walker
239 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
241 assert(node && node->kind==k_ir_node);
243 if (get_interprocedural_view()) {
244 eset * irg_set = eset_create();
245 unsigned long visited;
247 assert(get_irp_ip_view_state() == ip_view_valid);
249 set_interprocedural_view(0);
250 eset_insert(irg_set, current_ir_graph);
251 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
252 set_interprocedural_view(1);
253 visited = get_max_irg_visited() + 1;
254 for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
255 set_irg_visited(irg, visited);
257 irg_walk_cg(node, visited, irg_set, pre, post, env);
258 eset_destroy(irg_set);
260 inc_irg_visited(current_ir_graph);
261 nodes_touched = irg_walk_2(node, pre, post, env);
269 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
270 ir_graph * rem = current_ir_graph;
272 hook_irg_walk(irg, (generic_func *)pre, (generic_func *)post);
273 current_ir_graph = irg;
274 irg_walk(get_irg_end(irg), pre, post, env);
275 irg->estimated_node_count = nodes_touched;
276 current_ir_graph = rem;
279 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
280 Sets current_ir_graph properly for each walk. Conserves current
282 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
286 rem = current_ir_graph;
288 for (i = 0; i < get_irp_n_irgs(); i++) {
289 irg = get_irp_irg(i);
290 current_ir_graph = irg;
291 irg_walk(get_irg_end(irg), pre, post, env);
293 current_ir_graph = rem;
296 /***************************************************************************/
299 * Returns current_ir_graph and sets it to the irg of predecessor index
302 static INLINE ir_graph *
303 switch_irg (ir_node *n, int index) {
304 ir_graph *old_current = current_ir_graph;
306 if (get_interprocedural_view()) {
307 /* Only Filter and Block nodes can have predecessors in other graphs. */
308 if (get_irn_op(n) == op_Filter)
309 n = get_nodes_block(n);
310 if (get_irn_op(n) == op_Block) {
311 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
312 if (is_ip_cfop(cfop)) {
313 current_ir_graph = get_irn_irg(cfop);
322 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
325 ir_graph *rem = NULL;
328 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
329 set_irn_visited(node, get_irg_visited(current_ir_graph));
331 if (pre) pre(node, env);
333 if (is_no_Block(node))
334 cg_walk_2(get_nodes_block(node), pre, post, env);
335 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
336 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
337 switch to the irg of the predecessor, don't we? */
338 cg_walk_2(get_irn_n(node, i), pre, post, env);
339 current_ir_graph = rem;
342 if (post) post(node, env);
348 /* Walks all irgs in interprocedural view. Visits each node only once. */
349 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
351 ir_graph *rem = current_ir_graph;
352 int rem_view = get_interprocedural_view();
354 set_interprocedural_view(1);
356 inc_max_irg_visited();
357 /* Fix all irg_visited flags */
358 for (i = 0; i < get_irp_n_irgs(); i++)
359 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
361 /* Walk starting at unreachable procedures. Only these
362 * have End blocks visible in interprocedural view. */
363 for (i = 0; i < get_irp_n_irgs(); i++) {
365 current_ir_graph = get_irp_irg(i);
367 sb = get_irg_start_block(current_ir_graph);
369 if ((get_Block_n_cfgpreds(sb) > 1) ||
370 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
372 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
375 /* Check whether we walked all procedures: there could be procedures
376 with cyclic calls but no call from the outside. */
377 for (i = 0; i < get_irp_n_irgs(); i++) {
379 current_ir_graph = get_irp_irg(i);
381 /* Test start block: if inner procedure end and end block are not
382 * visible and therefore not marked. */
383 sb = get_irg_start_block(current_ir_graph);
384 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
385 cg_walk_2(sb, pre, post, env);
389 /* Walk all endless loops in inner procedures.
390 * We recognize an inner procedure if the End node is not visited. */
391 for (i = 0; i < get_irp_n_irgs(); i++) {
393 current_ir_graph = get_irp_irg(i);
394 e = get_irg_end(current_ir_graph);
395 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
397 /* Don't visit the End node. */
398 for (j = 0; j < get_End_n_keepalives(e); j++)
399 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
403 set_interprocedural_view(rem_view);
404 current_ir_graph = rem;
408 /***************************************************************************/
410 /* Walks back from n until it finds a real cf op. */
411 static ir_node *get_cf_op(ir_node *n) {
417 if (!(is_cfop(pred) || is_fragile_op(pred) ||
418 (get_irn_op(pred) == op_Bad)))
424 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
428 if (Block_not_block_visited(node)) {
429 mark_Block_block_visited(node);
431 if(pre) pre(node, env);
433 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
434 /* find the corresponding predecessor block. */
435 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
436 pred = get_nodes_block(pred);
437 if(get_irn_opcode(pred) == iro_Block) {
439 irg_block_walk_2(pred, pre, post, env);
442 assert(get_irn_opcode(pred) == iro_Bad);
446 if(post) post(node, env);
452 /* walks only over Block nodes in the graph. Has it's own visited
453 flag, so that it can be interleaved with the other walker. */
454 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
456 ir_node *block, *pred;
459 hook_irg_block_walk(current_ir_graph, node, (generic_func *)pre, (generic_func *)post);
462 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
463 * interleaves with irg_walk */
464 inc_irg_block_visited(current_ir_graph);
465 if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
466 assert(get_irn_op(block) == op_Block);
467 irg_block_walk_2(block, pre, post, env);
469 /* keepalive: the endless loops ... */
470 if (get_irn_op(node) == op_End) {
471 int arity = get_irn_arity(node);
472 for (i = 0; i < arity; i++) {
473 pred = get_irn_n(node, i);
474 if (get_irn_op(pred) == op_Block)
475 irg_block_walk_2(pred, pre, post, env);
477 /* Sometimes the blocks died, but are still reachable through Phis.
478 * Make sure the algorithms that try to remove these reach them. */
479 for (i = 0; i < arity; i++) {
480 pred = get_irn_n(node, i);
481 if (get_irn_op(pred) == op_Phi) {
482 ir_node *block = get_nodes_block(pred);
485 irg_block_walk_2(block, pre, post, env);
494 * walk over a graph block wise
496 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
497 irg_walk_func *post, void *env) {
498 ir_graph * rem = current_ir_graph;
499 current_ir_graph = irg;
500 irg_block_walk(get_irg_end(irg), pre, post, env);
501 current_ir_graph = rem;
504 /********************************************************************/
506 typedef struct walk_env {
513 * Walk to all constant expressions in this entity.
515 static void walk_entity(entity *ent, void *env)
517 walk_env *my_env = (walk_env *)env;
519 if (get_entity_variability(ent) != variability_uninitialized) {
520 if (is_atomic_entity(ent)) {
521 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
524 int i, n_vals = get_compound_ent_n_values(ent);
526 for (i = 0; i < n_vals; i++)
527 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
532 /* Walks over all code in const_code_irg. */
533 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
537 ir_graph *rem = current_ir_graph;
538 current_ir_graph = get_const_code_irg();
539 inc_irg_visited(current_ir_graph);
545 /* Walk all types that can contain constant entities. */
546 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
547 for (i = 0; i < get_irp_n_types(); i++)
548 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
549 for (i = 0; i < get_irp_n_irgs(); i++)
550 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
552 /* Walk constant array bounds. */
553 for (i = 0; i < get_irp_n_types(); i++) {
554 type *tp = get_irp_type(i);
555 if (is_Array_type(tp)) {
556 for (j = 0; j < get_array_n_dimensions(tp); j++) {
557 ir_node *n = get_array_lower_bound(tp, j);
558 if (n) irg_walk(n, pre, post, env);
559 n = get_array_upper_bound(tp, j);
560 if (n) irg_walk(n, pre, post, env);
565 current_ir_graph = rem;