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 if (pre) pre(node, env);
51 pred = skip_Proj(node);
52 if (get_irn_op(pred) == op_CallBegin
53 || get_irn_op(pred) == op_EndReg
54 || get_irn_op(pred) == op_EndExcept) {
55 current_ir_graph = get_irn_irg(pred);
58 if (is_no_Block(node)) { /* not block */
59 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
62 if (get_irn_op(node) == op_Block) { /* block */
63 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
64 ir_node * exec = get_irn_n(node, i);
65 ir_node * pred = skip_Proj(exec);
66 if ((get_irn_op(pred) != op_CallBegin
67 && get_irn_op(pred) != op_EndReg
68 && get_irn_op(pred) != op_EndExcept)
69 || eset_contains(irg_set, get_irn_irg(pred))) {
70 irg_walk_cg(exec, visited, irg_set, pre, post, env);
73 } else if (get_irn_op(node) == op_Filter) { /* filter */
74 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
75 ir_node * pred = get_irn_n(node, i);
76 if (get_irn_op(pred) == op_Unknown || get_irn_op(pred) == op_Bad) {
77 irg_walk_cg(pred, visited, irg_set, pre, post, env);
80 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
82 if (op_Bad == get_irn_op (exec)) {
86 assert(get_irn_op(exec) == op_CallBegin
87 || get_irn_op(exec) == op_EndReg
88 || get_irn_op(exec) == op_EndExcept);
89 if (eset_contains(irg_set, get_irn_irg(exec))) {
90 current_ir_graph = get_irn_irg(exec);
91 irg_walk_cg(pred, visited, irg_set, pre, post, env);
92 current_ir_graph = rem;
96 } else { /* everything else */
97 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
98 irg_walk_cg(get_irn_n(node, i), visited, irg_set, pre, post, env);
102 if (post) post(node, env);
104 current_ir_graph = rem;
108 /* Insert all ir_graphs in irg_set, that are (transitive) reachable. */
109 static void collect_irgs(ir_node * node, eset * irg_set) {
110 if (get_irn_op(node) == op_Call) {
112 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
113 entity * ent = get_Call_callee(node, i);
114 ir_graph * irg = ent ? get_entity_irg(ent) : NULL;
115 if (irg && !eset_contains(irg_set, irg)) {
116 eset_insert(irg_set, irg);
117 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
124 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
127 assert(node && node->kind==k_ir_node);
129 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
130 set_irn_visited(node, get_irg_visited(current_ir_graph));
132 if (pre) pre(node, env);
134 if (is_no_Block(node))
135 irg_walk_2(get_nodes_block(node), pre, post, env);
136 for (i = get_irn_arity(node) - 1; i >= 0; --i)
137 irg_walk_2(get_irn_n(node, i), pre, post, env);
139 if (post) post(node, env);
142 if (node->visited < current_ir_graph->visited) {
143 set_irn_visited(node, current_ir_graph->visited);
145 if (pre) pre(node, env);
147 if (node->op != op_Block)
148 irg_walk_2(get_irn_n(node, -1), pre, post, env);
149 for (i = get_irn_arity(node) - 1; i >= 0; --i)
150 irg_walk_2(get_irn_n(node, i), pre, post, env);
152 if (post) post(node, env);
158 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
160 assert(node && node->kind==k_ir_node);
162 if (interprocedural_view) {
163 eset * irg_set = eset_create();
166 assert(get_irp_ip_view_state() == ip_view_valid);
168 interprocedural_view = false;
169 eset_insert(irg_set, current_ir_graph);
170 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
171 interprocedural_view = true;
172 visited = get_max_irg_visited() + 1;
173 for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
174 set_irg_visited(irg, visited);
176 irg_walk_cg(node, visited, irg_set, pre, post, env);
177 eset_destroy(irg_set);
179 inc_irg_visited(current_ir_graph);
180 irg_walk_2(node, pre, post, env);
186 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
187 ir_graph * rem = current_ir_graph;
189 stat_irg_walk(irg, (void *)pre, (void *)post);
190 current_ir_graph = irg;
191 irg_walk(get_irg_end(irg), pre, post, env);
192 current_ir_graph = rem;
195 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
196 Sets current_ir_graph properly for each walk. Conserves current
198 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
202 rem = current_ir_graph;
204 for (i = 0; i < get_irp_n_irgs(); i++) {
205 irg = get_irp_irg(i);
206 current_ir_graph = irg;
207 irg_walk(get_irg_end(irg), pre, post, env);
209 current_ir_graph = rem;
212 /***************************************************************************/
214 /* Returns current_ir_graph and sets it to the irg of predecessor index
216 static INLINE ir_graph *
217 switch_irg (ir_node *n, int index) {
218 ir_graph *old_current = current_ir_graph;
220 if (interprocedural_view) {
221 /* Only Filter and Block nodes can have predecessors in other graphs. */
222 if (get_irn_op(n) == op_Filter)
223 n = get_nodes_block(n);
224 if (get_irn_op(n) == op_Block) {
225 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
226 if (is_ip_cfop(cfop)) {
227 current_ir_graph = get_irn_irg(cfop);
236 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
239 ir_graph *rem = NULL;
242 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
243 set_irn_visited(node, get_irg_visited(current_ir_graph));
245 if (pre) pre(node, env);
247 if (is_no_Block(node))
248 cg_walk_2(get_nodes_block(node), pre, post, env);
249 for (i = get_irn_arity(node) - 1; i >= 0; --i) {
250 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
251 switch to the irg of the predecessor, don't we? */
252 cg_walk_2(get_irn_n(node, i), pre, post, env);
253 current_ir_graph = rem;
256 if (post) post(node, env);
262 /* Walks all irgs in interprocedural view. Visits each node only once. */
263 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
265 ir_graph *rem = current_ir_graph;
266 int rem_view = interprocedural_view;
268 interprocedural_view = true;
270 inc_max_irg_visited();
271 /* Fix all irg_visited flags */
272 for (i = 0; i < get_irp_n_irgs(); i++)
273 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
275 /* Walk starting at unreachable procedures. Only these
276 * have End blocks visible in interprocedural view. */
277 for (i = 0; i < get_irp_n_irgs(); i++) {
279 current_ir_graph = get_irp_irg(i);
281 sb = get_irg_start_block(current_ir_graph);
283 if ((get_Block_n_cfgpreds(sb) > 1) ||
284 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
286 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
289 /* Check whether we walked all procedures: there could be procedures
290 with cyclic calls but no call from the outside. */
291 for (i = 0; i < get_irp_n_irgs(); i++) {
293 current_ir_graph = get_irp_irg(i);
295 /* Test start block: if inner procedure end and end block are not
296 * visible and therefore not marked. */
297 sb = get_irg_start_block(current_ir_graph);
298 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
299 cg_walk_2(sb, pre, post, env);
303 /* Walk all endless loops in inner procedures.
304 * We recognize an inner procedure if the End node is not visited. */
305 for (i = 0; i < get_irp_n_irgs(); i++) {
307 current_ir_graph = get_irp_irg(i);
308 e = get_irg_end(current_ir_graph);
309 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
311 /* Don't visit the End node. */
312 for (j = 0; j < get_End_n_keepalives(e); j++)
313 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
317 interprocedural_view = rem_view;
318 current_ir_graph = rem;
322 /***************************************************************************/
324 /* Walks back from n until it finds a real cf op. */
325 static ir_node *get_cf_op(ir_node *n) {
331 if (!(is_cfop(pred) || is_fragile_op(pred) ||
332 (get_irn_op(pred) == op_Bad)))
338 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
342 if(get_Block_block_visited(node) < get_irg_block_visited(current_ir_graph)) {
343 set_Block_block_visited(node, get_irg_block_visited(current_ir_graph));
345 if(pre) pre(node, env);
347 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
348 /* find the corresponding predecessor block. */
349 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
350 pred = get_nodes_block(pred);
351 if(get_irn_opcode(pred) == iro_Block) {
353 irg_block_walk_2(pred, pre, post, env);
356 assert(get_irn_opcode(pred) == iro_Bad);
360 if(post) post(node, env);
366 /* walks only over Block nodes in the graph. Has it's own visited
367 flag, so that it can be interleaved with the other walker. */
368 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
370 ir_node *block, *pred;
373 stat_irg_block_walk(current_ir_graph, node, (void *)pre, (void *)post);
376 assert(!interprocedural_view); /* interprocedural_view not implemented, because it
377 * interleaves with irg_walk */
378 inc_irg_block_visited(current_ir_graph);
379 if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
380 assert(get_irn_opcode(block) == iro_Block);
381 irg_block_walk_2(block, pre, post, env);
382 /* keepalive: the endless loops ... */
383 if (get_irn_op(node) == op_End) {
384 int arity = get_irn_arity(node);
385 for (i = 0; i < arity; i++) {
386 pred = get_irn_n(node, i);
387 if (get_irn_op(pred) == op_Block)
388 irg_block_walk_2(pred, pre, post, env);
396 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
397 irg_walk_func *post, void *env) {
398 ir_graph * rem = current_ir_graph;
399 current_ir_graph = irg;
400 irg_block_walk(get_irg_end(irg), pre, post, env);
401 current_ir_graph = rem;
404 /********************************************************************/
406 typedef struct walk_env {
412 /* Walk to all constant expressions in this entity. */
413 static void walk_entity(entity *ent, void *env)
415 walk_env *my_env = (walk_env *)env;
417 if (get_entity_variability(ent) != variability_uninitialized) {
418 if (is_atomic_entity(ent)) {
419 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
422 int i, n = get_compound_ent_n_values(ent);
424 for (i = 0; i < n; i++)
425 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
430 /* Walks over all code in const_code_irg. */
431 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
435 ir_graph *rem = current_ir_graph;
436 current_ir_graph = get_const_code_irg();
437 inc_irg_visited(current_ir_graph);
443 /* Walk all types that can contain constant entities. */
444 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
445 for (i = 0; i < get_irp_n_types(); i++)
446 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
447 for (i = 0; i < get_irp_n_irgs(); i++)
448 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
450 /* Walk constant array bounds. */
451 for (i = 0; i < get_irp_n_types(); i++) {
452 type *tp = get_irp_type(i);
453 if (is_array_type(tp)) {
454 for (j = 0; j < get_array_n_dimensions(tp); j++) {
456 n = get_array_lower_bound(tp, j);
457 if (n) irg_walk(n, pre, post, env);
458 n = get_array_upper_bound(tp, j);
459 if (n) irg_walk(n, pre, post, env);
464 current_ir_graph = rem;
468 /********************************************************************/
469 /** Walking support for interprocedural analysis **/
471 /** @@@ Don't use, not operational yet, doesn't grok recursions!! **/
472 /** @@@ Header for irgwalk.h, here until it works. **/
474 /** Interprocedural walking should not walk all predecessors of **/
475 /** all nodes. When leaving a procedure the walker should only **/
476 /** follow the edge corresponding to the most recent entry of the **/
477 /** procedure. The following functions use an internal stack to **/
478 /** remember the current call site of a procedure. **/
479 /** They also set current_ir_graph correctly. **/
481 /** Usage example: **/
483 /** void init_ip_walk (); **/
484 /** work_on_graph(some_end_node); **/
485 /** void finish_ip_walk(); **/
487 /** work_on_graph(ir_node *n) { **/
488 /** for (i = 0; i < get_irn_arity(n); i++) { **/
489 /** if (...) continue; **/
490 /** ir_node *m = get_irn_ip_pred(n, i); **/
491 /** if !m continue; **/
492 /** work_on_graph(m); **/
493 /** return_recur(n, i); **/
496 /********************************************************************/
498 /* Call for i in {0|-1 ... get_irn_arity(n)}.
499 If n is a conventional node returns the same node as get_irn_n(n, i).
500 If the predecessors of n are in the callee of the procedure n belongs
501 to, returns get_irn_n(n, i) if this node is in the callee on the top
502 of the stack, else returns NULL.
503 If the predecessors of n are in a procedure called by the procedure n
504 belongs to pushes the caller on the caller stack in the callee.
505 Sets current_ir_graph to the graph the node returned is in. */
506 ir_node *get_irn_ip_pred(ir_node *n, int pos);
508 /* If get_irn_ip_pred() returned a node (not NULL) this must be
509 called to clear up the stacks.
510 Sets current_ir_graph to the graph n is in. */
511 void return_recur(ir_node *n, int pos);
514 /********************************************************************/
515 /** Walking support for interprocedural analysis **/
516 /********************************************************************/
518 #define MIN_STACK_SIZE 40
520 typedef struct callsite_stack {
525 /* Access the stack in the irg **************************************/
528 set_irg_callsite_stack(ir_graph *g, callsite_stack *s) {
532 static INLINE callsite_stack *
533 get_irg_callsite_stack(ir_graph *g) {
534 return (callsite_stack *) get_irg_link(g);
537 /* A stack of callsites *********************************************/
539 /* @@@ eventually change the implementation so the new_ only sets the field
540 to NULL, and the stack is only allocated if used. Saves Memory! */
541 static INLINE callsite_stack *
542 new_callsite_stack(ir_graph *g) {
543 callsite_stack *res = (callsite_stack *)malloc(sizeof(callsite_stack));
545 res->s = NEW_ARR_F (ir_node *, MIN_STACK_SIZE);
546 set_irg_callsite_stack(g, res);
551 free_callsite_stack(ir_graph *g) {
552 callsite_stack *s = get_irg_callsite_stack(g);
558 push_callsite(ir_graph *callee, ir_node *callsite) {
559 callsite_stack *s = get_irg_callsite_stack(callee);
560 if (s->tos == ARR_LEN(s->s)) {
561 int nlen = ARR_LEN (s->s) * 2;
562 ARR_RESIZE (ir_node *, s->s, nlen);
564 s->s[s->tos] = callsite;
568 static INLINE ir_node *
569 get_top_of_callsite_stack(ir_graph *callee) {
570 callsite_stack *s = get_irg_callsite_stack(callee);
571 return (s->s[s->tos-1]);
575 ir_node * pop_callsite(ir_graph *callee) {
576 callsite_stack *s = get_irg_callsite_stack(callee);
578 return (s->s[s->tos]);
582 /* Initialization routines ******************************************/
584 void init_ip_walk (void) {
586 for (i = 0; i < get_irp_n_irgs(); i++)
587 new_callsite_stack(get_irp_irg(i));
590 void finish_ip_walk(void) {
592 for (i = 0; i < get_irp_n_irgs(); i++)
593 free_callsite_stack(get_irp_irg(i));
594 set_irg_link(get_irp_irg(i), NULL);
597 /* walker routines **************************************************/
599 /* cf_pred is End* */
601 enter_procedure(ir_node *block, ir_node *cf_pred, int pos) {
603 ir_graph *irg = get_irn_irg(cf_pred);
605 assert(interprocedural_view);
607 interprocedural_view = 0;
608 callbegin = skip_Proj(get_irn_n(block, 0));
609 assert(get_irn_op(callbegin) == op_CallBegin);
610 interprocedural_view = 1;
612 push_callsite(irg, callbegin);
613 current_ir_graph = irg;
616 /* cf_pred is CallBegin */
618 leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
619 ir_node *tos = get_top_of_callsite_stack(current_ir_graph);
621 assert(get_irn_op(cf_pred) == op_CallBegin);
623 if (tos == cf_pred) {
624 /* We entered this procedure by the call pred pos refers to. */
625 pop_callsite(current_ir_graph);
626 current_ir_graph = get_CallBegin_irg(cf_pred);
634 ir_node *get_irn_ip_pred(ir_node *n, int pos) {
636 if (interprocedural_view) {
638 /* Find the cf_pred refering to pos. */
641 if (get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
642 cf_pred = skip_Proj(get_irn_n(block, pos));
644 /* Check whether we enter or leave a procedure and act according. */
645 if ((get_irn_op(cf_pred) == op_EndReg) ||
646 (get_irn_op(cf_pred) == op_EndExcept))
647 enter_procedure(block, cf_pred, pos);
648 if (get_irn_op(cf_pred) == op_CallBegin)
649 if (!leave_procedure(block, cf_pred, pos)) return NULL;
652 return get_irn_n(n, pos);
656 re_enter_procedure(ir_node *block, ir_node *cf_pred, int pos) {
657 ir_node *callbegin = pop_callsite(current_ir_graph);
658 assert(interprocedural_view);
659 current_ir_graph = get_CallBegin_irg(callbegin);
663 re_leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
667 assert(get_irn_op(cf_pred) == op_CallBegin);
669 /* Find the irg block is in. */
670 proj = get_Block_cg_cfgpred(block, pos);
671 assert(is_Proj(proj));
672 callee = get_entity_irg(get_Call_callee(get_CallBegin_call(cf_pred),
673 get_Proj_proj(proj)));
674 current_ir_graph = callee;
675 push_callsite(callee, cf_pred);
679 return_recur(ir_node *n, int pos) {
683 if (!interprocedural_view) return;
685 /* Find the cf_pred refering to pos. */
687 if (get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
688 cf_pred = skip_Proj(get_irn_n(block, pos));
690 /* Check whether we re_enter or re_leave a procedure and act according. */
691 if ((get_irn_op(cf_pred) == op_EndReg) ||
692 (get_irn_op(cf_pred) == op_EndExcept))
693 re_enter_procedure(block, cf_pred, pos);
694 if (get_irn_op(cf_pred) == op_CallBegin)
695 re_leave_procedure(block, cf_pred, pos);