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, int 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
136 irg_walk_2_pre(ir_node *node, irg_walk_func *pre, void * env) {
138 set_irn_visited(node, current_ir_graph->visited);
142 if (node->op != op_Block) {
143 ir_node *pred = get_irn_n(node, -1);
144 if (pred->visited < current_ir_graph->visited)
145 irg_walk_2_pre(pred, pre, env);
147 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
148 ir_node *pred = get_irn_n(node, i);
149 if (pred->visited < current_ir_graph->visited)
150 irg_walk_2_pre(pred, pre, env);
155 * specialized version of irg_walk_2, called if only post callback exists
158 irg_walk_2_post(ir_node *node, irg_walk_func *post, void * env) {
160 set_irn_visited(node, current_ir_graph->visited);
162 if (node->op != op_Block) {
163 ir_node *pred = get_irn_n(node, -1);
164 if (pred->visited < current_ir_graph->visited)
165 irg_walk_2_post(pred, post, env);
167 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
168 ir_node *pred = get_irn_n(node, i);
169 if (pred->visited < current_ir_graph->visited)
170 irg_walk_2_post(pred, post, env);
177 * specialized version of irg_walk_2, called if pre and post callbacks exist
180 irg_walk_2_both(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env) {
182 set_irn_visited(node, current_ir_graph->visited);
186 if (node->op != op_Block) {
187 ir_node *pred = get_irn_n(node, -1);
188 if (pred->visited < current_ir_graph->visited)
189 irg_walk_2_both(pred, pre, post, env);
191 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
192 ir_node *pred = get_irn_n(node, i);
193 if (pred->visited < current_ir_graph->visited)
194 irg_walk_2_both(pred, pre, post, env);
201 * Intraprozedural graph walker.
204 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
206 if (node->visited < current_ir_graph->visited) {
207 if (!post) irg_walk_2_pre (node, pre, env);
208 else if (!pre) irg_walk_2_post(node, post, env);
209 else irg_walk_2_both(node, pre, post, env);
214 * generic graph walker
216 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
218 assert(node && node->kind==k_ir_node);
220 if (get_interprocedural_view()) {
221 eset * irg_set = eset_create();
224 assert(get_irp_ip_view_state() == ip_view_valid);
226 set_interprocedural_view(false);
227 eset_insert(irg_set, current_ir_graph);
228 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
229 set_interprocedural_view(true);
230 visited = get_max_irg_visited() + 1;
231 for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
232 set_irg_visited(irg, visited);
234 irg_walk_cg(node, visited, irg_set, pre, post, env);
235 eset_destroy(irg_set);
237 inc_irg_visited(current_ir_graph);
238 irg_walk_2(node, pre, post, env);
246 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
247 ir_graph * rem = current_ir_graph;
249 stat_irg_walk(irg, (void *)pre, (void *)post);
250 current_ir_graph = irg;
251 irg_walk(get_irg_end(irg), pre, post, env);
252 current_ir_graph = rem;
255 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
256 Sets current_ir_graph properly for each walk. Conserves current
258 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
262 rem = current_ir_graph;
264 for (i = 0; i < get_irp_n_irgs(); i++) {
265 irg = get_irp_irg(i);
266 current_ir_graph = irg;
267 irg_walk(get_irg_end(irg), pre, post, env);
269 current_ir_graph = rem;
272 /***************************************************************************/
274 /* Returns current_ir_graph and sets it to the irg of predecessor index
276 static INLINE ir_graph *
277 switch_irg (ir_node *n, int index) {
278 ir_graph *old_current = current_ir_graph;
280 if (get_interprocedural_view()) {
281 /* Only Filter and Block nodes can have predecessors in other graphs. */
282 if (get_irn_op(n) == op_Filter)
283 n = get_nodes_block(n);
284 if (get_irn_op(n) == op_Block) {
285 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
286 if (is_ip_cfop(cfop)) {
287 current_ir_graph = get_irn_irg(cfop);
296 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
299 ir_graph *rem = NULL;
302 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
303 set_irn_visited(node, get_irg_visited(current_ir_graph));
305 if (pre) pre(node, env);
307 if (is_no_Block(node))
308 cg_walk_2(get_nodes_block(node), pre, post, env);
309 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
310 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
311 switch to the irg of the predecessor, don't we? */
312 cg_walk_2(get_irn_n(node, i), pre, post, env);
313 current_ir_graph = rem;
316 if (post) post(node, env);
322 /* Walks all irgs in interprocedural view. Visits each node only once. */
323 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
325 ir_graph *rem = current_ir_graph;
326 int rem_view = get_interprocedural_view();
328 set_interprocedural_view(true);
330 inc_max_irg_visited();
331 /* Fix all irg_visited flags */
332 for (i = 0; i < get_irp_n_irgs(); i++)
333 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
335 /* Walk starting at unreachable procedures. Only these
336 * have End blocks visible in interprocedural view. */
337 for (i = 0; i < get_irp_n_irgs(); i++) {
339 current_ir_graph = get_irp_irg(i);
341 sb = get_irg_start_block(current_ir_graph);
343 if ((get_Block_n_cfgpreds(sb) > 1) ||
344 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
346 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
349 /* Check whether we walked all procedures: there could be procedures
350 with cyclic calls but no call from the outside. */
351 for (i = 0; i < get_irp_n_irgs(); i++) {
353 current_ir_graph = get_irp_irg(i);
355 /* Test start block: if inner procedure end and end block are not
356 * visible and therefore not marked. */
357 sb = get_irg_start_block(current_ir_graph);
358 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
359 cg_walk_2(sb, pre, post, env);
363 /* Walk all endless loops in inner procedures.
364 * We recognize an inner procedure if the End node is not visited. */
365 for (i = 0; i < get_irp_n_irgs(); i++) {
367 current_ir_graph = get_irp_irg(i);
368 e = get_irg_end(current_ir_graph);
369 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
371 /* Don't visit the End node. */
372 for (j = 0; j < get_End_n_keepalives(e); j++)
373 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
377 set_interprocedural_view(rem_view);
378 current_ir_graph = rem;
382 /***************************************************************************/
384 /* Walks back from n until it finds a real cf op. */
385 static ir_node *get_cf_op(ir_node *n) {
391 if (!(is_cfop(pred) || is_fragile_op(pred) ||
392 (get_irn_op(pred) == op_Bad)))
398 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
402 if(get_Block_block_visited(node) < get_irg_block_visited(current_ir_graph)) {
403 set_Block_block_visited(node, get_irg_block_visited(current_ir_graph));
405 if(pre) pre(node, env);
407 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
408 /* find the corresponding predecessor block. */
409 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
410 pred = get_nodes_block(pred);
411 if(get_irn_opcode(pred) == iro_Block) {
413 irg_block_walk_2(pred, pre, post, env);
416 assert(get_irn_opcode(pred) == iro_Bad);
420 if(post) post(node, env);
426 /* walks only over Block nodes in the graph. Has it's own visited
427 flag, so that it can be interleaved with the other walker. */
428 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
430 ir_node *block, *pred;
433 stat_irg_block_walk(current_ir_graph, node, (void *)pre, (void *)post);
436 assert(!get_interprocedural_view()); /* interprocedural_view not implemented, because it
437 * interleaves with irg_walk */
438 inc_irg_block_visited(current_ir_graph);
439 if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
440 assert(get_irn_opcode(block) == iro_Block);
441 irg_block_walk_2(block, pre, post, env);
443 /* keepalive: the endless loops ... */
444 if (get_irn_op(node) == op_End) {
445 int arity = get_irn_arity(node);
446 for (i = 0; i < arity; i++) {
447 pred = get_irn_n(node, i);
448 if (get_irn_op(pred) == op_Block)
449 irg_block_walk_2(pred, pre, post, env);
451 /* Sometimes the blocks died, but are still reachable through Phis.
452 * Make sure the algorithms that try to remove these reach them. */
453 for (i = 0; i < arity; i++) {
454 pred = get_irn_n(node, i);
455 if (get_irn_op(pred) == op_Phi) {
456 ir_node *block = get_nodes_block(pred);
459 irg_block_walk_2(block, pre, post, env);
468 * walk over a graph block wise
470 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
471 irg_walk_func *post, void *env) {
472 ir_graph * rem = current_ir_graph;
473 current_ir_graph = irg;
474 irg_block_walk(get_irg_end(irg), pre, post, env);
475 current_ir_graph = rem;
478 /********************************************************************/
480 typedef struct walk_env {
487 * Walk to all constant expressions in this entity.
489 static void walk_entity(entity *ent, void *env)
491 walk_env *my_env = (walk_env *)env;
493 if (get_entity_variability(ent) != variability_uninitialized) {
494 if (is_atomic_entity(ent)) {
495 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
498 int i, n_vals = get_compound_ent_n_values(ent);
500 for (i = 0; i < n_vals; i++)
501 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
506 /* Walks over all code in const_code_irg. */
507 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
511 ir_graph *rem = current_ir_graph;
512 current_ir_graph = get_const_code_irg();
513 inc_irg_visited(current_ir_graph);
519 /* Walk all types that can contain constant entities. */
520 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
521 for (i = 0; i < get_irp_n_types(); i++)
522 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
523 for (i = 0; i < get_irp_n_irgs(); i++)
524 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
526 /* Walk constant array bounds. */
527 for (i = 0; i < get_irp_n_types(); i++) {
528 type *tp = get_irp_type(i);
529 if (is_array_type(tp)) {
530 for (j = 0; j < get_array_n_dimensions(tp); j++) {
531 ir_node *n = get_array_lower_bound(tp, j);
532 if (n) irg_walk(n, pre, post, env);
533 n = get_array_upper_bound(tp, j);
534 if (n) irg_walk(n, pre, post, env);
539 current_ir_graph = rem;