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
26 # include "irnode_t.h"
27 # include "irgraph.h" /* visited flag */
30 # include "typewalk.h"
35 /* walk over an interprocedural graph (callgraph). Visits only graphs in irg_set. */
36 static void irg_walk_cg(ir_node * node, int visited, eset * irg_set,
37 irg_walk_func *pre, irg_walk_func *post, void * env) {
39 ir_graph * rem = current_ir_graph;
42 assert(node && node->kind == k_ir_node);
43 if (get_irn_visited(node) >= visited) return;
45 set_irn_visited(node, visited);
47 pred = skip_Proj(node);
48 if (get_irn_op(pred) == op_CallBegin
49 || get_irn_op(pred) == op_EndReg
50 || get_irn_op(pred) == op_EndExcept) {
51 current_ir_graph = get_irn_irg(pred);
54 if (pre) pre(node, env);
56 if (is_no_Block(node))
57 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
59 if (get_irn_op(node) == op_Block) { /* block */
60 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
61 ir_node * exec = get_irn_n(node, i);
62 ir_node * pred = skip_Proj(exec);
63 if ((get_irn_op(pred) != op_CallBegin
64 && get_irn_op(pred) != op_EndReg
65 && get_irn_op(pred) != op_EndExcept)
66 || eset_contains(irg_set, get_irn_irg(pred))) {
67 irg_walk_cg(exec, visited, irg_set, pre, post, env);
70 } else if (get_irn_op(node) == op_Filter) {
71 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
72 ir_node * pred = get_irn_n(node, i);
73 if (get_irn_op(pred) == op_Unknown || get_irn_op(pred) == op_Bad) {
74 irg_walk_cg(pred, visited, irg_set, pre, post, env);
77 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
78 assert(get_irn_op(exec) == op_CallBegin
79 || get_irn_op(exec) == op_EndReg
80 || get_irn_op(exec) == op_EndExcept);
81 if (eset_contains(irg_set, get_irn_irg(exec))) {
82 current_ir_graph = get_irn_irg(exec);
83 irg_walk_cg(pred, visited, irg_set, pre, post, env);
84 current_ir_graph = rem;
89 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
90 irg_walk_cg(get_irn_n(node, i), visited, irg_set, pre, post, env);
94 if (post) post(node, env);
96 current_ir_graph = rem;
100 /* Insert all ir_graphs in irg_set, that are (transitive) reachable. */
101 static void collect_irgs(ir_node * node, eset * irg_set) {
102 if (get_irn_op(node) == op_Call) {
104 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
105 entity * ent = get_Call_callee(node, i);
106 ir_graph * irg = ent ? get_entity_irg(ent) : NULL;
107 if (irg && !eset_contains(irg_set, irg)) {
108 eset_insert(irg_set, irg);
109 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
116 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
119 assert(node && node->kind==k_ir_node);
121 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
122 set_irn_visited(node, get_irg_visited(current_ir_graph));
124 if (pre) pre(node, env);
126 if (is_no_Block(node))
127 irg_walk_2(get_nodes_block(node), pre, post, env);
128 for (i = get_irn_arity(node) - 1; i >= 0; --i)
129 irg_walk_2(get_irn_n(node, i), pre, post, env);
131 if (post) post(node, env);
137 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
139 assert(node && node->kind==k_ir_node);
140 if (interprocedural_view) {
141 eset * irg_set = eset_create();
144 interprocedural_view = false;
145 eset_insert(irg_set, current_ir_graph);
146 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
147 interprocedural_view = true;
148 visited = get_max_irg_visited() + 1;
149 for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
150 set_irg_visited(irg, visited);
152 irg_walk_cg(node, visited, irg_set, pre, post, env);
153 eset_destroy(irg_set);
155 inc_irg_visited(current_ir_graph);
156 irg_walk_2(node, pre, post, env);
162 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
163 ir_graph * rem = current_ir_graph;
164 current_ir_graph = irg;
165 irg_walk(get_irg_end(irg), pre, post, env);
166 current_ir_graph = rem;
169 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
170 Sets current_ir_graph properly for each walk. Conserves current
172 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
176 rem = current_ir_graph;
178 for (i = 0; i < get_irp_n_irgs(); i++) {
179 irg = get_irp_irg(i);
180 current_ir_graph = irg;
181 irg_walk(get_irg_end(irg), pre, post, env);
183 current_ir_graph = rem;
186 /***************************************************************************/
188 /* Returns current_ir_graph and sets it to the irg of predecessor index
190 static INLINE ir_graph *
191 switch_irg (ir_node *n, int index) {
192 ir_graph *old_current = current_ir_graph;
194 if (interprocedural_view) {
195 /* Only Filter and Block nodes can have predecessors in other graphs. */
196 if (get_irn_op(n) == op_Filter)
197 n = get_nodes_block(n);
198 if (get_irn_op(n) == op_Block) {
199 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
200 if (is_ip_cfop(cfop)) {
201 current_ir_graph = get_irn_irg(cfop);
210 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
213 ir_graph *rem = NULL;
216 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
217 set_irn_visited(node, get_irg_visited(current_ir_graph));
219 if (pre) pre(node, env);
221 if (is_no_Block(node))
222 cg_walk_2(get_nodes_block(node), pre, post, env);
223 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
224 rem = switch_irg(node, i);
225 cg_walk_2(get_irn_n(node, i), pre, post, env);
226 current_ir_graph = rem;
229 if (post) post(node, env);
235 /* Walks all irgs in interprocedural view. Visits each node only once. */
236 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
238 ir_graph *rem = current_ir_graph;
239 int rem_view = interprocedural_view;
241 interprocedural_view = true;
243 inc_max_irg_visited();
244 /* Fix all irg_visited flags */
245 for (i = 0; i < get_irp_n_irgs(); i++)
246 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
248 /* Walk starting at unreachable procedures. Only these
249 * have End blocks visible in interprocedural view. */
250 for (i = 0; i < get_irp_n_irgs(); i++) {
252 current_ir_graph = get_irp_irg(i);
254 sb = get_irg_start_block(current_ir_graph);
256 if ((get_Block_n_cfgpreds(sb) > 1) ||
257 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
259 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
262 /* Check whether we walked all procedures: there could be procedures
263 with cyclic calls but no call from the outside. */
264 for (i = 0; i < get_irp_n_irgs(); i++) {
266 current_ir_graph = get_irp_irg(i);
268 /* Test start block: if inner procedure end and end block are not
269 * visible and therefore not marked. */
270 sb = get_irg_start_block(current_ir_graph);
271 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
272 cg_walk_2(sb, pre, post, env);
276 /* Walk all endless loops in inner procedures.
277 * We recognize an inner procedure if the End node is not visited. */
278 for (i = 0; i < get_irp_n_irgs(); i++) {
280 current_ir_graph = get_irp_irg(i);
281 e = get_irg_end(current_ir_graph);
282 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
284 /* Don't visit the End node. */
285 for (j = 0; j < get_End_n_keepalives(e); j++)
286 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
290 interprocedural_view = rem_view;
291 current_ir_graph = rem;
295 /***************************************************************************/
297 /* Walks back from n until it finds a real cf op. */
298 static ir_node *get_cf_op(ir_node *n) {
304 if (!(is_cfop(pred) || is_fragile_op(pred) ||
305 (get_irn_op(pred) == op_Bad)))
311 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
314 assert(get_irn_opcode(node) == iro_Block);
316 if(get_Block_block_visited(node) < get_irg_block_visited(current_ir_graph)) {
317 set_Block_block_visited(node, get_irg_block_visited(current_ir_graph));
319 if(pre) pre(node, env);
321 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
322 /* find the corresponding predecessor block. */
323 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
324 pred = get_nodes_block(pred);
325 if(get_irn_opcode(pred) == iro_Block) {
327 irg_block_walk_2(pred, pre, post, env);
330 assert(get_irn_opcode(pred) == iro_Bad);
334 if(post) post(node, env);
340 /* walks only over Block nodes in the graph. Has it's own visited
341 flag, so that it can be interleaved with the other walker. */
342 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
344 ir_node *block, *pred;
348 assert(!interprocedural_view); /* interprocedural_view not implemented, because it
349 * interleaves with irg_walk */
350 inc_irg_block_visited(current_ir_graph);
351 if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
352 assert(get_irn_opcode(block) == iro_Block);
353 irg_block_walk_2(block, pre, post, env);
354 /* keepalive: the endless loops ... */
355 if (get_irn_op(node) == op_End)
356 for (i = 0; i < get_irn_arity(node); i++) {
357 pred = get_irn_n(node, i);
358 if (get_irn_op(pred) == op_Block)
359 irg_block_walk_2(pred, pre, post, env);
366 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
367 irg_walk_func *post, void *env) {
368 ir_graph * rem = current_ir_graph;
369 current_ir_graph = irg;
370 irg_block_walk(get_irg_end(irg), pre, post, env);
371 current_ir_graph = rem;
374 /********************************************************************/
376 typedef struct walk_env {
382 /* Walk to all constant expressions in this entity. */
383 static void walk_entity(entity *ent, void *env)
385 walk_env *my_env = (walk_env *)env;
387 if (get_entity_variability(ent) != variability_uninitialized) {
388 if (is_atomic_entity(ent)) {
389 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
392 int i, n = get_compound_ent_n_values(ent);
394 for (i = 0; i < n; i++)
395 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
400 /* Walks over all code in const_code_irg. */
401 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
405 ir_graph *rem = current_ir_graph;
406 current_ir_graph = get_const_code_irg();
407 inc_irg_visited(current_ir_graph);
413 /* Walk all types that can contain constant entities. */
414 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
415 for (i = 0; i < get_irp_n_types(); i++)
416 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
417 for (i = 0; i < get_irp_n_irgs(); i++)
418 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
420 /* Walk constant array bounds. */
421 for (i = 0; i < get_irp_n_types(); i++) {
422 type *tp = get_irp_type(i);
423 if (is_array_type(tp)) {
424 for (j = 0; j < get_array_n_dimensions(tp); j++) {
426 n = get_array_lower_bound(tp, j);
427 if (n) irg_walk(n, pre, post, env);
428 n = get_array_upper_bound(tp, j);
429 if (n) irg_walk(n, pre, post, env);
434 current_ir_graph = rem;
438 /********************************************************************/
439 /** Walking support for interprocedural analysis **/
441 /** @@@ Don't use, not operational yet, doesn't grok recursions!! **/
442 /** @@@ Header for irgwalk.h, here until it works. **/
444 /** Interprocedural walking should not walk all predecessors of **/
445 /** all nodes. When leaving a procedure the walker should only **/
446 /** follow the edge corresponding to the most recent entry of the **/
447 /** procedure. The following functions use an internal stack to **/
448 /** remember the current call site of a procedure. **/
449 /** They also set current_ir_graph correctly. **/
451 /** Usage example: **/
453 /** void init_ip_walk (); **/
454 /** work_on_graph(some_end_node); **/
455 /** void finish_ip_walk(); **/
457 /** work_on_graph(ir_node *n) { **/
458 /** for (i = 0; i < get_irn_arity(n); i++) { **/
459 /** if (...) continue; **/
460 /** ir_node *m = get_irn_ip_pred(n, i); **/
461 /** if !m continue; **/
462 /** work_on_graph(m); **/
463 /** return_recur(n, i); **/
466 /********************************************************************/
468 /* Call for i in {0|-1 ... get_irn_arity(n)}.
469 If n is a conventional node returns the same node as get_irn_n(n, i).
470 If the predecessors of n are in the callee of the procedure n belongs
471 to, returns get_irn_n(n, i) if this node is in the callee on the top
472 of the stack, else returns NULL.
473 If the predecessors of n are in a procedure called by the procedure n
474 belongs to pushes the caller on the caller stack in the callee.
475 Sets current_ir_graph to the graph the node returned is in. */
476 ir_node *get_irn_ip_pred(ir_node *n, int pos);
478 /* If get_irn_ip_pred() returned a node (not NULL) this must be
479 called to clear up the stacks.
480 Sets current_ir_graph to the graph n is in. */
481 void return_recur(ir_node *n, int pos);
484 /********************************************************************/
485 /** Walking support for interprocedural analysis **/
486 /********************************************************************/
488 #define MIN_STACK_SIZE 40
490 typedef struct callsite_stack {
495 /* Access the stack in the irg **************************************/
498 set_irg_callsite_stack(ir_graph *g, callsite_stack *s) {
502 static INLINE callsite_stack *
503 get_irg_callsite_stack(ir_graph *g) {
504 return (callsite_stack *) get_irg_link(g);
507 /* A stack of callsites *********************************************/
509 /* @@@ eventually change the implementation so the new_ only sets the field
510 to NULL, and the stack is only allocated if used. Saves Memory! */
511 static INLINE callsite_stack *
512 new_callsite_stack(ir_graph *g) {
513 callsite_stack *res = (callsite_stack *)malloc(sizeof(callsite_stack));
515 res->s = NEW_ARR_F (ir_node *, MIN_STACK_SIZE);
516 set_irg_callsite_stack(g, res);
521 free_callsite_stack(ir_graph *g) {
522 callsite_stack *s = get_irg_callsite_stack(g);
528 push_callsite(ir_graph *callee, ir_node *callsite) {
529 callsite_stack *s = get_irg_callsite_stack(callee);
530 if (s->tos == ARR_LEN(s->s)) {
531 int nlen = ARR_LEN (s->s) * 2;
532 ARR_RESIZE (ir_node *, s->s, nlen);
534 s->s[s->tos] = callsite;
538 static INLINE ir_node *
539 get_top_of_callsite_stack(ir_graph *callee) {
540 callsite_stack *s = get_irg_callsite_stack(callee);
541 return (s->s[s->tos-1]);
545 ir_node * pop_callsite(ir_graph *callee) {
546 callsite_stack *s = get_irg_callsite_stack(callee);
548 return (s->s[s->tos]);
552 /* Initialization routines ******************************************/
554 void init_ip_walk (void) {
556 for (i = 0; i < get_irp_n_irgs(); i++)
557 new_callsite_stack(get_irp_irg(i));
560 void finish_ip_walk(void) {
562 for (i = 0; i < get_irp_n_irgs(); i++)
563 free_callsite_stack(get_irp_irg(i));
564 set_irg_link(get_irp_irg(i), NULL);
567 /* walker routines **************************************************/
569 /* cf_pred is End* */
571 enter_procedure(ir_node *block, ir_node *cf_pred, int pos) {
573 ir_graph *irg = get_irn_irg(cf_pred);
575 assert(interprocedural_view);
577 interprocedural_view = 0;
578 callbegin = skip_Proj(get_irn_n(block, 0));
579 assert(get_irn_op(callbegin) == op_CallBegin);
580 interprocedural_view = 1;
582 push_callsite(irg, callbegin);
583 current_ir_graph = irg;
586 /* cf_pred is CallBegin */
588 leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
589 ir_node *tos = get_top_of_callsite_stack(current_ir_graph);
591 assert(get_irn_op(cf_pred) == op_CallBegin);
593 if (tos == cf_pred) {
594 /* We entered this procedure by the call pred pos refers to. */
595 pop_callsite(current_ir_graph);
596 current_ir_graph = get_CallBegin_irg(cf_pred);
604 ir_node *get_irn_ip_pred(ir_node *n, int pos) {
606 if (interprocedural_view) {
608 /* Find the cf_pred refering to pos. */
611 if (get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
612 cf_pred = skip_Proj(get_irn_n(block, pos));
614 /* Check whether we enter or leave a procedure and act according. */
615 if ((get_irn_op(cf_pred) == op_EndReg) ||
616 (get_irn_op(cf_pred) == op_EndExcept))
617 enter_procedure(block, cf_pred, pos);
618 if (get_irn_op(cf_pred) == op_CallBegin)
619 if (!leave_procedure(block, cf_pred, pos)) return NULL;
622 return get_irn_n(n, pos);
626 re_enter_procedure(ir_node *block, ir_node *cf_pred, int pos) {
627 ir_node *callbegin = pop_callsite(current_ir_graph);
628 assert(interprocedural_view);
629 current_ir_graph = get_CallBegin_irg(callbegin);
633 re_leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
637 assert(get_irn_op(cf_pred) == op_CallBegin);
639 /* Find the irg block is in. */
640 proj = get_Block_cg_cfgpred(block, pos);
641 assert(is_Proj(proj));
642 callee = get_entity_irg(get_Call_callee(get_CallBegin_call(cf_pred),
643 get_Proj_proj(proj)));
644 current_ir_graph = callee;
645 push_callsite(callee, cf_pred);
649 return_recur(ir_node *n, int pos) {
653 if (!interprocedural_view) return;
655 /* Find the cf_pred refering to pos. */
657 if (get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
658 cf_pred = skip_Proj(get_irn_n(block, pos));
660 /* Check whether we re_enter or re_leave a procedure and act according. */
661 if ((get_irn_op(cf_pred) == op_EndReg) ||
662 (get_irn_op(cf_pred) == op_EndExcept))
663 re_enter_procedure(block, cf_pred, pos);
664 if (get_irn_op(cf_pred) == op_CallBegin)
665 re_leave_procedure(block, cf_pred, pos);