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_t.h" /* visited flag */
30 # include "typewalk.h"
31 # include "firmstat.h"
32 # include "ircgcons.h"
37 /* walk over an interprocedural graph (callgraph). Visits only graphs in irg_set. */
38 static void irg_walk_cg(ir_node * node, int visited, eset * irg_set,
39 irg_walk_func *pre, irg_walk_func *post, void * env) {
41 ir_graph * rem = current_ir_graph;
44 assert(node && node->kind == k_ir_node);
45 if (get_irn_visited(node) >= visited) return;
47 set_irn_visited(node, visited);
49 pred = skip_Proj(node);
50 if (intern_get_irn_op(pred) == op_CallBegin
51 || intern_get_irn_op(pred) == op_EndReg
52 || intern_get_irn_op(pred) == op_EndExcept) {
53 current_ir_graph = get_irn_irg(pred);
56 if (pre) pre(node, env);
58 if (is_no_Block(node))
59 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
61 if (intern_get_irn_op(node) == op_Block) { /* block */
62 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i) {
63 ir_node * exec = intern_get_irn_n(node, i);
64 ir_node * pred = skip_Proj(exec);
65 if ((intern_get_irn_op(pred) != op_CallBegin
66 && intern_get_irn_op(pred) != op_EndReg
67 && intern_get_irn_op(pred) != op_EndExcept)
68 || eset_contains(irg_set, get_irn_irg(pred))) {
69 irg_walk_cg(exec, visited, irg_set, pre, post, env);
72 } else if (intern_get_irn_op(node) == op_Filter) {
73 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i) {
74 ir_node * pred = intern_get_irn_n(node, i);
75 if (intern_get_irn_op(pred) == op_Unknown || intern_get_irn_op(pred) == op_Bad) {
76 irg_walk_cg(pred, visited, irg_set, pre, post, env);
79 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
80 assert(intern_get_irn_op(exec) == op_CallBegin
81 || intern_get_irn_op(exec) == op_EndReg
82 || intern_get_irn_op(exec) == op_EndExcept);
83 if (eset_contains(irg_set, get_irn_irg(exec))) {
84 current_ir_graph = get_irn_irg(exec);
85 irg_walk_cg(pred, visited, irg_set, pre, post, env);
86 current_ir_graph = rem;
91 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i) {
92 irg_walk_cg(intern_get_irn_n(node, i), visited, irg_set, pre, post, env);
96 if (post) post(node, env);
98 current_ir_graph = rem;
102 /* Insert all ir_graphs in irg_set, that are (transitive) reachable. */
103 static void collect_irgs(ir_node * node, eset * irg_set) {
104 if (intern_get_irn_op(node) == op_Call) {
106 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
107 entity * ent = get_Call_callee(node, i);
108 ir_graph * irg = ent ? get_entity_irg(ent) : NULL;
109 if (irg && !eset_contains(irg_set, irg)) {
110 eset_insert(irg_set, irg);
111 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
118 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
121 assert(node && node->kind==k_ir_node);
123 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
124 set_irn_visited(node, get_irg_visited(current_ir_graph));
126 if (pre) pre(node, env);
128 if (is_no_Block(node))
129 irg_walk_2(get_nodes_block(node), pre, post, env);
130 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i)
131 irg_walk_2(intern_get_irn_n(node, i), pre, post, env);
133 if (post) post(node, env);
136 if (node->visited < current_ir_graph->visited) {
137 set_irn_visited(node, current_ir_graph->visited);
139 if (pre) pre(node, env);
141 if (node->op != op_Block)
142 irg_walk_2(intern_get_irn_n(node, -1), pre, post, env);
143 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i)
144 irg_walk_2(intern_get_irn_n(node, i), pre, post, env);
146 if (post) post(node, env);
152 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
154 assert(node && node->kind==k_ir_node);
156 if (interprocedural_view) {
157 eset * irg_set = eset_create();
160 assert(get_irp_ip_view_state() == ip_view_valid);
162 interprocedural_view = false;
163 eset_insert(irg_set, current_ir_graph);
164 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
165 interprocedural_view = true;
166 visited = get_max_irg_visited() + 1;
167 for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
168 set_irg_visited(irg, visited);
170 irg_walk_cg(node, visited, irg_set, pre, post, env);
171 eset_destroy(irg_set);
173 inc_irg_visited(current_ir_graph);
174 irg_walk_2(node, pre, post, env);
180 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
181 ir_graph * rem = current_ir_graph;
183 stat_irg_walk(irg, (void *)pre, (void *)post);
184 current_ir_graph = irg;
185 irg_walk(get_irg_end(irg), pre, post, env);
186 current_ir_graph = rem;
189 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
190 Sets current_ir_graph properly for each walk. Conserves current
192 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
196 rem = current_ir_graph;
198 for (i = 0; i < get_irp_n_irgs(); i++) {
199 irg = get_irp_irg(i);
200 current_ir_graph = irg;
201 irg_walk(get_irg_end(irg), pre, post, env);
203 current_ir_graph = rem;
206 /***************************************************************************/
208 /* Returns current_ir_graph and sets it to the irg of predecessor index
210 static INLINE ir_graph *
211 switch_irg (ir_node *n, int index) {
212 ir_graph *old_current = current_ir_graph;
214 if (interprocedural_view) {
215 /* Only Filter and Block nodes can have predecessors in other graphs. */
216 if (intern_get_irn_op(n) == op_Filter)
217 n = get_nodes_block(n);
218 if (intern_get_irn_op(n) == op_Block) {
219 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
220 if (is_ip_cfop(cfop)) {
221 current_ir_graph = get_irn_irg(cfop);
230 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
233 ir_graph *rem = NULL;
236 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
237 set_irn_visited(node, get_irg_visited(current_ir_graph));
239 if (pre) pre(node, env);
241 if (is_no_Block(node))
242 cg_walk_2(get_nodes_block(node), pre, post, env);
243 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i) {
244 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
245 switch to the irg of the predecessor, don't we? */
246 cg_walk_2(intern_get_irn_n(node, i), pre, post, env);
247 current_ir_graph = rem;
250 if (post) post(node, env);
256 /* Walks all irgs in interprocedural view. Visits each node only once. */
257 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
259 ir_graph *rem = current_ir_graph;
260 int rem_view = interprocedural_view;
262 interprocedural_view = true;
264 inc_max_irg_visited();
265 /* Fix all irg_visited flags */
266 for (i = 0; i < get_irp_n_irgs(); i++)
267 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
269 /* Walk starting at unreachable procedures. Only these
270 * have End blocks visible in interprocedural view. */
271 for (i = 0; i < get_irp_n_irgs(); i++) {
273 current_ir_graph = get_irp_irg(i);
275 sb = get_irg_start_block(current_ir_graph);
277 if ((get_Block_n_cfgpreds(sb) > 1) ||
278 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
280 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
283 /* Check whether we walked all procedures: there could be procedures
284 with cyclic calls but no call from the outside. */
285 for (i = 0; i < get_irp_n_irgs(); i++) {
287 current_ir_graph = get_irp_irg(i);
289 /* Test start block: if inner procedure end and end block are not
290 * visible and therefore not marked. */
291 sb = get_irg_start_block(current_ir_graph);
292 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
293 cg_walk_2(sb, pre, post, env);
297 /* Walk all endless loops in inner procedures.
298 * We recognize an inner procedure if the End node is not visited. */
299 for (i = 0; i < get_irp_n_irgs(); i++) {
301 current_ir_graph = get_irp_irg(i);
302 e = get_irg_end(current_ir_graph);
303 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
305 /* Don't visit the End node. */
306 for (j = 0; j < get_End_n_keepalives(e); j++)
307 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
311 interprocedural_view = rem_view;
312 current_ir_graph = rem;
316 /***************************************************************************/
318 /* Walks back from n until it finds a real cf op. */
319 static ir_node *get_cf_op(ir_node *n) {
325 if (!(is_cfop(pred) || is_fragile_op(pred) ||
326 (intern_get_irn_op(pred) == op_Bad)))
332 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
336 if(get_Block_block_visited(node) < get_irg_block_visited(current_ir_graph)) {
337 set_Block_block_visited(node, get_irg_block_visited(current_ir_graph));
339 if(pre) pre(node, env);
341 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
342 /* find the corresponding predecessor block. */
343 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
344 pred = get_nodes_block(pred);
345 if(intern_get_irn_opcode(pred) == iro_Block) {
347 irg_block_walk_2(pred, pre, post, env);
350 assert(get_irn_opcode(pred) == iro_Bad);
354 if(post) post(node, env);
360 /* walks only over Block nodes in the graph. Has it's own visited
361 flag, so that it can be interleaved with the other walker. */
362 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
364 ir_node *block, *pred;
367 stat_irg_block_walk(current_ir_graph, node, (void *)pre, (void *)post);
370 assert(!interprocedural_view); /* interprocedural_view not implemented, because it
371 * interleaves with irg_walk */
372 inc_irg_block_visited(current_ir_graph);
373 if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
374 assert(get_irn_opcode(block) == iro_Block);
375 irg_block_walk_2(block, pre, post, env);
376 /* keepalive: the endless loops ... */
377 if (intern_get_irn_op(node) == op_End) {
378 int arity = intern_get_irn_arity(node);
379 for (i = 0; i < arity; i++) {
380 pred = intern_get_irn_n(node, i);
381 if (intern_get_irn_op(pred) == op_Block)
382 irg_block_walk_2(pred, pre, post, env);
390 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
391 irg_walk_func *post, void *env) {
392 ir_graph * rem = current_ir_graph;
393 current_ir_graph = irg;
394 irg_block_walk(get_irg_end(irg), pre, post, env);
395 current_ir_graph = rem;
398 /********************************************************************/
400 typedef struct walk_env {
406 /* Walk to all constant expressions in this entity. */
407 static void walk_entity(entity *ent, void *env)
409 walk_env *my_env = (walk_env *)env;
411 if (get_entity_variability(ent) != variability_uninitialized) {
412 if (is_atomic_entity(ent)) {
413 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
416 int i, n = get_compound_ent_n_values(ent);
418 for (i = 0; i < n; i++)
419 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
424 /* Walks over all code in const_code_irg. */
425 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
429 ir_graph *rem = current_ir_graph;
430 current_ir_graph = get_const_code_irg();
431 inc_irg_visited(current_ir_graph);
437 /* Walk all types that can contain constant entities. */
438 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
439 for (i = 0; i < get_irp_n_types(); i++)
440 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
441 for (i = 0; i < get_irp_n_irgs(); i++)
442 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
444 /* Walk constant array bounds. */
445 for (i = 0; i < get_irp_n_types(); i++) {
446 type *tp = get_irp_type(i);
447 if (is_array_type(tp)) {
448 for (j = 0; j < get_array_n_dimensions(tp); j++) {
450 n = get_array_lower_bound(tp, j);
451 if (n) irg_walk(n, pre, post, env);
452 n = get_array_upper_bound(tp, j);
453 if (n) irg_walk(n, pre, post, env);
458 current_ir_graph = rem;
462 /********************************************************************/
463 /** Walking support for interprocedural analysis **/
465 /** @@@ Don't use, not operational yet, doesn't grok recursions!! **/
466 /** @@@ Header for irgwalk.h, here until it works. **/
468 /** Interprocedural walking should not walk all predecessors of **/
469 /** all nodes. When leaving a procedure the walker should only **/
470 /** follow the edge corresponding to the most recent entry of the **/
471 /** procedure. The following functions use an internal stack to **/
472 /** remember the current call site of a procedure. **/
473 /** They also set current_ir_graph correctly. **/
475 /** Usage example: **/
477 /** void init_ip_walk (); **/
478 /** work_on_graph(some_end_node); **/
479 /** void finish_ip_walk(); **/
481 /** work_on_graph(ir_node *n) { **/
482 /** for (i = 0; i < get_irn_arity(n); i++) { **/
483 /** if (...) continue; **/
484 /** ir_node *m = get_irn_ip_pred(n, i); **/
485 /** if !m continue; **/
486 /** work_on_graph(m); **/
487 /** return_recur(n, i); **/
490 /********************************************************************/
492 /* Call for i in {0|-1 ... get_irn_arity(n)}.
493 If n is a conventional node returns the same node as get_irn_n(n, i).
494 If the predecessors of n are in the callee of the procedure n belongs
495 to, returns get_irn_n(n, i) if this node is in the callee on the top
496 of the stack, else returns NULL.
497 If the predecessors of n are in a procedure called by the procedure n
498 belongs to pushes the caller on the caller stack in the callee.
499 Sets current_ir_graph to the graph the node returned is in. */
500 ir_node *get_irn_ip_pred(ir_node *n, int pos);
502 /* If get_irn_ip_pred() returned a node (not NULL) this must be
503 called to clear up the stacks.
504 Sets current_ir_graph to the graph n is in. */
505 void return_recur(ir_node *n, int pos);
508 /********************************************************************/
509 /** Walking support for interprocedural analysis **/
510 /********************************************************************/
512 #define MIN_STACK_SIZE 40
514 typedef struct callsite_stack {
519 /* Access the stack in the irg **************************************/
522 set_irg_callsite_stack(ir_graph *g, callsite_stack *s) {
526 static INLINE callsite_stack *
527 get_irg_callsite_stack(ir_graph *g) {
528 return (callsite_stack *) get_irg_link(g);
531 /* A stack of callsites *********************************************/
533 /* @@@ eventually change the implementation so the new_ only sets the field
534 to NULL, and the stack is only allocated if used. Saves Memory! */
535 static INLINE callsite_stack *
536 new_callsite_stack(ir_graph *g) {
537 callsite_stack *res = (callsite_stack *)malloc(sizeof(callsite_stack));
539 res->s = NEW_ARR_F (ir_node *, MIN_STACK_SIZE);
540 set_irg_callsite_stack(g, res);
545 free_callsite_stack(ir_graph *g) {
546 callsite_stack *s = get_irg_callsite_stack(g);
552 push_callsite(ir_graph *callee, ir_node *callsite) {
553 callsite_stack *s = get_irg_callsite_stack(callee);
554 if (s->tos == ARR_LEN(s->s)) {
555 int nlen = ARR_LEN (s->s) * 2;
556 ARR_RESIZE (ir_node *, s->s, nlen);
558 s->s[s->tos] = callsite;
562 static INLINE ir_node *
563 get_top_of_callsite_stack(ir_graph *callee) {
564 callsite_stack *s = get_irg_callsite_stack(callee);
565 return (s->s[s->tos-1]);
569 ir_node * pop_callsite(ir_graph *callee) {
570 callsite_stack *s = get_irg_callsite_stack(callee);
572 return (s->s[s->tos]);
576 /* Initialization routines ******************************************/
578 void init_ip_walk (void) {
580 for (i = 0; i < get_irp_n_irgs(); i++)
581 new_callsite_stack(get_irp_irg(i));
584 void finish_ip_walk(void) {
586 for (i = 0; i < get_irp_n_irgs(); i++)
587 free_callsite_stack(get_irp_irg(i));
588 set_irg_link(get_irp_irg(i), NULL);
591 /* walker routines **************************************************/
593 /* cf_pred is End* */
595 enter_procedure(ir_node *block, ir_node *cf_pred, int pos) {
597 ir_graph *irg = get_irn_irg(cf_pred);
599 assert(interprocedural_view);
601 interprocedural_view = 0;
602 callbegin = skip_Proj(intern_get_irn_n(block, 0));
603 assert(intern_get_irn_op(callbegin) == op_CallBegin);
604 interprocedural_view = 1;
606 push_callsite(irg, callbegin);
607 current_ir_graph = irg;
610 /* cf_pred is CallBegin */
612 leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
613 ir_node *tos = get_top_of_callsite_stack(current_ir_graph);
615 assert(get_irn_op(cf_pred) == op_CallBegin);
617 if (tos == cf_pred) {
618 /* We entered this procedure by the call pred pos refers to. */
619 pop_callsite(current_ir_graph);
620 current_ir_graph = get_CallBegin_irg(cf_pred);
628 ir_node *get_irn_ip_pred(ir_node *n, int pos) {
630 if (interprocedural_view) {
632 /* Find the cf_pred refering to pos. */
635 if (intern_get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
636 cf_pred = skip_Proj(intern_get_irn_n(block, pos));
638 /* Check whether we enter or leave a procedure and act according. */
639 if ((intern_get_irn_op(cf_pred) == op_EndReg) ||
640 (intern_get_irn_op(cf_pred) == op_EndExcept))
641 enter_procedure(block, cf_pred, pos);
642 if (intern_get_irn_op(cf_pred) == op_CallBegin)
643 if (!leave_procedure(block, cf_pred, pos)) return NULL;
646 return intern_get_irn_n(n, pos);
650 re_enter_procedure(ir_node *block, ir_node *cf_pred, int pos) {
651 ir_node *callbegin = pop_callsite(current_ir_graph);
652 assert(interprocedural_view);
653 current_ir_graph = get_CallBegin_irg(callbegin);
657 re_leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
661 assert(get_irn_op(cf_pred) == op_CallBegin);
663 /* Find the irg block is in. */
664 proj = get_Block_cg_cfgpred(block, pos);
665 assert(is_Proj(proj));
666 callee = get_entity_irg(get_Call_callee(get_CallBegin_call(cf_pred),
667 get_Proj_proj(proj)));
668 current_ir_graph = callee;
669 push_callsite(callee, cf_pred);
673 return_recur(ir_node *n, int pos) {
677 if (!interprocedural_view) return;
679 /* Find the cf_pred refering to pos. */
681 if (intern_get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
682 cf_pred = skip_Proj(intern_get_irn_n(block, pos));
684 /* Check whether we re_enter or re_leave a procedure and act according. */
685 if ((intern_get_irn_op(cf_pred) == op_EndReg) ||
686 (intern_get_irn_op(cf_pred) == op_EndExcept))
687 re_enter_procedure(block, cf_pred, pos);
688 if (intern_get_irn_op(cf_pred) == op_CallBegin)
689 re_leave_procedure(block, cf_pred, pos);