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.
14 * traverse an ir graph
15 * - execute the pre function before recursion
16 * - execute the post function after recursion
27 #include "irgraph_t.h" /* visited flag */
38 * Walk over an interprocedural graph (callgraph).
39 * Visits only graphs in irg_set.
41 static void irg_walk_cg(ir_node * node, int visited, eset * irg_set,
42 irg_walk_func *pre, irg_walk_func *post, void * env) {
44 ir_graph * rem = current_ir_graph;
47 assert(node && node->kind == k_ir_node);
48 if (get_irn_visited(node) >= visited) return;
50 set_irn_visited(node, visited);
52 if (pre) pre(node, env);
54 pred = skip_Proj(node);
55 if (get_irn_op(pred) == op_CallBegin
56 || get_irn_op(pred) == op_EndReg
57 || get_irn_op(pred) == op_EndExcept) {
58 current_ir_graph = get_irn_irg(pred);
61 if (is_no_Block(node)) { /* not block */
62 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
65 if (get_irn_op(node) == op_Block) { /* block */
66 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
67 ir_node * exec = get_irn_n(node, i);
68 ir_node * pred = skip_Proj(exec);
69 if ((get_irn_op(pred) != op_CallBegin
70 && get_irn_op(pred) != op_EndReg
71 && get_irn_op(pred) != op_EndExcept)
72 || eset_contains(irg_set, get_irn_irg(pred))) {
73 irg_walk_cg(exec, visited, irg_set, pre, post, env);
76 } else if (get_irn_op(node) == op_Filter) { /* filter */
77 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
78 ir_node * pred = get_irn_n(node, i);
79 if (get_irn_op(pred) == op_Unknown || get_irn_op(pred) == op_Bad) {
80 irg_walk_cg(pred, visited, irg_set, pre, post, env);
83 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
85 if (op_Bad == get_irn_op (exec)) {
89 assert(get_irn_op(exec) == op_CallBegin
90 || get_irn_op(exec) == op_EndReg
91 || get_irn_op(exec) == op_EndExcept);
92 if (eset_contains(irg_set, get_irn_irg(exec))) {
93 current_ir_graph = get_irn_irg(exec);
94 irg_walk_cg(pred, visited, irg_set, pre, post, env);
95 current_ir_graph = rem;
99 } else { /* everything else */
100 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
101 irg_walk_cg(get_irn_n(node, i), visited, irg_set, pre, post, env);
105 if (post) post(node, env);
107 current_ir_graph = rem;
112 * Insert all ir_graphs in irg_set, that are (transitive) reachable.
114 static void collect_irgs(ir_node * node, eset * irg_set) {
115 if (get_irn_op(node) == op_Call) {
117 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
118 entity * ent = get_Call_callee(node, i);
119 ir_graph * irg = get_entity_irg(ent);
120 if (irg && !eset_contains(irg_set, irg)) {
121 eset_insert(irg_set, irg);
122 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
129 * specialized version of irg_walk_2, called if only pre callback exists
132 irg_walk_2_pre(ir_node *node, irg_walk_func *pre, void * env) {
134 set_irn_visited(node, current_ir_graph->visited);
138 if (node->op != op_Block) {
139 ir_node *pred = get_irn_n(node, -1);
140 if (pred->visited < current_ir_graph->visited)
141 irg_walk_2_pre(pred, pre, env);
143 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
144 ir_node *pred = get_irn_n(node, i);
145 if (pred->visited < current_ir_graph->visited)
146 irg_walk_2_pre(pred, pre, env);
151 * specialized version of irg_walk_2, called if only post callback exists
154 irg_walk_2_post(ir_node *node, irg_walk_func *post, void * env) {
156 set_irn_visited(node, current_ir_graph->visited);
158 if (node->op != op_Block) {
159 ir_node *pred = get_irn_n(node, -1);
160 if (pred->visited < current_ir_graph->visited)
161 irg_walk_2_post(pred, post, 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 < current_ir_graph->visited)
166 irg_walk_2_post(pred, post, env);
173 * specialized version of irg_walk_2, called if pre and post callbacks exist
176 irg_walk_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env) {
178 set_irn_visited(node, current_ir_graph->visited);
182 if (node->op != op_Block) {
183 ir_node *pred = get_irn_n(node, -1);
184 if (pred->visited < current_ir_graph->visited)
185 irg_walk_2_both(pred, pre, post, env);
187 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
188 ir_node *pred = get_irn_n(node, i);
189 if (pred->visited < current_ir_graph->visited)
190 irg_walk_2_both(pred, pre, post, env);
197 * Intraprozedural graph walker.
200 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
202 if (node->visited < current_ir_graph->visited) {
203 if (!post) irg_walk_2_pre (node, pre, env);
204 else if (!pre) irg_walk_2_post(node, post, env);
205 else irg_walk_2_both(node, pre, post, env);
210 * generic graph walker
212 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
214 assert(node && node->kind==k_ir_node);
216 if (get_interprocedural_view()) {
217 eset * irg_set = eset_create();
220 assert(get_irp_ip_view_state() == ip_view_valid);
222 set_interprocedural_view(false);
223 eset_insert(irg_set, current_ir_graph);
224 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
225 set_interprocedural_view(true);
226 visited = get_max_irg_visited() + 1;
227 for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
228 set_irg_visited(irg, visited);
230 irg_walk_cg(node, visited, irg_set, pre, post, env);
231 eset_destroy(irg_set);
233 inc_irg_visited(current_ir_graph);
234 irg_walk_2(node, pre, post, env);
242 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
243 ir_graph * rem = current_ir_graph;
245 stat_irg_walk(irg, (void *)pre, (void *)post);
246 current_ir_graph = irg;
247 irg_walk(get_irg_end(irg), pre, post, env);
248 current_ir_graph = rem;
251 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
252 Sets current_ir_graph properly for each walk. Conserves current
254 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
258 rem = current_ir_graph;
260 for (i = 0; i < get_irp_n_irgs(); i++) {
261 irg = get_irp_irg(i);
262 current_ir_graph = irg;
263 irg_walk(get_irg_end(irg), pre, post, env);
265 current_ir_graph = rem;
268 /***************************************************************************/
270 /* Returns current_ir_graph and sets it to the irg of predecessor index
272 static INLINE ir_graph *
273 switch_irg (ir_node *n, int index) {
274 ir_graph *old_current = current_ir_graph;
276 if (get_interprocedural_view()) {
277 /* Only Filter and Block nodes can have predecessors in other graphs. */
278 if (get_irn_op(n) == op_Filter)
279 n = get_nodes_block(n);
280 if (get_irn_op(n) == op_Block) {
281 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
282 if (is_ip_cfop(cfop)) {
283 current_ir_graph = get_irn_irg(cfop);
292 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
295 ir_graph *rem = NULL;
298 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
299 set_irn_visited(node, get_irg_visited(current_ir_graph));
301 if (pre) pre(node, env);
303 if (is_no_Block(node))
304 cg_walk_2(get_nodes_block(node), pre, post, env);
305 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
306 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
307 switch to the irg of the predecessor, don't we? */
308 cg_walk_2(get_irn_n(node, i), pre, post, env);
309 current_ir_graph = rem;
312 if (post) post(node, env);
318 /* Walks all irgs in interprocedural view. Visits each node only once. */
319 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
321 ir_graph *rem = current_ir_graph;
322 int rem_view = get_interprocedural_view();
324 set_interprocedural_view(true);
326 inc_max_irg_visited();
327 /* Fix all irg_visited flags */
328 for (i = 0; i < get_irp_n_irgs(); i++)
329 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
331 /* Walk starting at unreachable procedures. Only these
332 * have End blocks visible in interprocedural view. */
333 for (i = 0; i < get_irp_n_irgs(); i++) {
335 current_ir_graph = get_irp_irg(i);
337 sb = get_irg_start_block(current_ir_graph);
339 if ((get_Block_n_cfgpreds(sb) > 1) ||
340 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
342 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
345 /* Check whether we walked all procedures: there could be procedures
346 with cyclic calls but no call from the outside. */
347 for (i = 0; i < get_irp_n_irgs(); i++) {
349 current_ir_graph = get_irp_irg(i);
351 /* Test start block: if inner procedure end and end block are not
352 * visible and therefore not marked. */
353 sb = get_irg_start_block(current_ir_graph);
354 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
355 cg_walk_2(sb, pre, post, env);
359 /* Walk all endless loops in inner procedures.
360 * We recognize an inner procedure if the End node is not visited. */
361 for (i = 0; i < get_irp_n_irgs(); i++) {
363 current_ir_graph = get_irp_irg(i);
364 e = get_irg_end(current_ir_graph);
365 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
367 /* Don't visit the End node. */
368 for (j = 0; j < get_End_n_keepalives(e); j++)
369 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
373 set_interprocedural_view(rem_view);
374 current_ir_graph = rem;
378 /***************************************************************************/
380 /* Walks back from n until it finds a real cf op. */
381 static ir_node *get_cf_op(ir_node *n) {
387 if (!(is_cfop(pred) || is_fragile_op(pred) ||
388 (get_irn_op(pred) == op_Bad)))
394 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
398 if(get_Block_block_visited(node) < get_irg_block_visited(current_ir_graph)) {
399 set_Block_block_visited(node, get_irg_block_visited(current_ir_graph));
401 if(pre) pre(node, env);
403 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
404 /* find the corresponding predecessor block. */
405 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
406 pred = get_nodes_block(pred);
407 if(get_irn_opcode(pred) == iro_Block) {
409 irg_block_walk_2(pred, pre, post, env);
412 assert(get_irn_opcode(pred) == iro_Bad);
416 if(post) post(node, env);
422 /* walks only over Block nodes in the graph. Has it's own visited
423 flag, so that it can be interleaved with the other walker. */
424 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
426 ir_node *block, *pred;
429 stat_irg_block_walk(current_ir_graph, node, (void *)pre, (void *)post);
432 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
433 * interleaves with irg_walk */
434 inc_irg_block_visited(current_ir_graph);
435 if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
436 assert(get_irn_opcode(block) == iro_Block);
437 irg_block_walk_2(block, pre, post, env);
439 /* keepalive: the endless loops ... */
440 if (get_irn_op(node) == op_End) {
441 int arity = get_irn_arity(node);
442 for (i = 0; i < arity; i++) {
443 pred = get_irn_n(node, i);
444 if (get_irn_op(pred) == op_Block)
445 irg_block_walk_2(pred, pre, post, env);
447 /* Sometimes the blocks died, but are still reachable through Phis.
448 * Make sure the algorithms that try to remove these reach them. */
449 for (i = 0; i < arity; i++) {
450 pred = get_irn_n(node, i);
451 if (get_irn_op(pred) == op_Phi) {
452 ir_node *block = get_nodes_block(pred);
455 irg_block_walk_2(block, pre, post, env);
464 * walk over a graph block wise
466 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
467 irg_walk_func *post, void *env) {
468 ir_graph * rem = current_ir_graph;
469 current_ir_graph = irg;
470 irg_block_walk(get_irg_end(irg), pre, post, env);
471 current_ir_graph = rem;
474 /********************************************************************/
476 typedef struct walk_env {
483 * Walk to all constant expressions in this entity.
485 static void walk_entity(entity *ent, void *env)
487 walk_env *my_env = (walk_env *)env;
489 if (get_entity_variability(ent) != variability_uninitialized) {
490 if (is_atomic_entity(ent)) {
491 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
494 int i, n_vals = get_compound_ent_n_values(ent);
496 for (i = 0; i < n_vals; i++)
497 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
502 /* Walks over all code in const_code_irg. */
503 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
507 ir_graph *rem = current_ir_graph;
508 current_ir_graph = get_const_code_irg();
509 inc_irg_visited(current_ir_graph);
515 /* Walk all types that can contain constant entities. */
516 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
517 for (i = 0; i < get_irp_n_types(); i++)
518 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
519 for (i = 0; i < get_irp_n_irgs(); i++)
520 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
522 /* Walk constant array bounds. */
523 for (i = 0; i < get_irp_n_types(); i++) {
524 type *tp = get_irp_type(i);
525 if (is_array_type(tp)) {
526 for (j = 0; j < get_array_n_dimensions(tp); j++) {
527 ir_node *n = get_array_lower_bound(tp, j);
528 if (n) irg_walk(n, pre, post, env);
529 n = get_array_upper_bound(tp, j);
530 if (n) irg_walk(n, pre, post, env);
535 current_ir_graph = rem;