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"
36 /* walk over an interprocedural graph (callgraph). Visits only graphs in irg_set. */
37 static void irg_walk_cg(ir_node * node, int visited, eset * irg_set,
38 irg_walk_func *pre, irg_walk_func *post, void * env) {
40 ir_graph * rem = current_ir_graph;
43 assert(node && node->kind == k_ir_node);
44 if (get_irn_visited(node) >= visited) return;
46 set_irn_visited(node, visited);
48 pred = skip_Proj(node);
49 if (intern_get_irn_op(pred) == op_CallBegin
50 || intern_get_irn_op(pred) == op_EndReg
51 || intern_get_irn_op(pred) == op_EndExcept) {
52 current_ir_graph = get_irn_irg(pred);
55 if (pre) pre(node, env);
57 if (is_no_Block(node))
58 irg_walk_cg(get_nodes_block(node), visited, irg_set, pre, post, env);
60 if (intern_get_irn_op(node) == op_Block) { /* block */
61 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i) {
62 ir_node * exec = intern_get_irn_n(node, i);
63 ir_node * pred = skip_Proj(exec);
64 if ((intern_get_irn_op(pred) != op_CallBegin
65 && intern_get_irn_op(pred) != op_EndReg
66 && intern_get_irn_op(pred) != op_EndExcept)
67 || eset_contains(irg_set, get_irn_irg(pred))) {
68 irg_walk_cg(exec, visited, irg_set, pre, post, env);
71 } else if (intern_get_irn_op(node) == op_Filter) {
72 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i) {
73 ir_node * pred = intern_get_irn_n(node, i);
74 if (intern_get_irn_op(pred) == op_Unknown || intern_get_irn_op(pred) == op_Bad) {
75 irg_walk_cg(pred, visited, irg_set, pre, post, env);
78 exec = skip_Proj(get_Block_cfgpred(get_nodes_block(node), i));
79 assert(intern_get_irn_op(exec) == op_CallBegin
80 || intern_get_irn_op(exec) == op_EndReg
81 || intern_get_irn_op(exec) == op_EndExcept);
82 if (eset_contains(irg_set, get_irn_irg(exec))) {
83 current_ir_graph = get_irn_irg(exec);
84 irg_walk_cg(pred, visited, irg_set, pre, post, env);
85 current_ir_graph = rem;
90 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i) {
91 irg_walk_cg(intern_get_irn_n(node, i), visited, irg_set, pre, post, env);
95 if (post) post(node, env);
97 current_ir_graph = rem;
101 /* Insert all ir_graphs in irg_set, that are (transitive) reachable. */
102 static void collect_irgs(ir_node * node, eset * irg_set) {
103 if (intern_get_irn_op(node) == op_Call) {
105 for (i = get_Call_n_callees(node) - 1; i >= 0; --i) {
106 entity * ent = get_Call_callee(node, i);
107 ir_graph * irg = ent ? get_entity_irg(ent) : NULL;
108 if (irg && !eset_contains(irg_set, irg)) {
109 eset_insert(irg_set, irg);
110 irg_walk_graph(irg, (irg_walk_func *) collect_irgs, NULL, irg_set);
117 irg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
120 assert(node && node->kind==k_ir_node);
122 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
123 set_irn_visited(node, get_irg_visited(current_ir_graph));
125 if (pre) pre(node, env);
127 if (is_no_Block(node))
128 irg_walk_2(get_nodes_block(node), pre, post, env);
129 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i)
130 irg_walk_2(intern_get_irn_n(node, i), pre, post, env);
132 if (post) post(node, env);
135 if (node->visited < current_ir_graph->visited) {
136 set_irn_visited(node, current_ir_graph->visited);
138 if (pre) pre(node, env);
140 if (node->op != op_Block)
141 irg_walk_2(intern_get_irn_n(node, -1), pre, post, env);
142 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i)
143 irg_walk_2(intern_get_irn_n(node, i), pre, post, env);
145 if (post) post(node, env);
151 void irg_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
153 assert(node && node->kind==k_ir_node);
154 if (interprocedural_view) {
155 eset * irg_set = eset_create();
158 interprocedural_view = false;
159 eset_insert(irg_set, current_ir_graph);
160 irg_walk(node, (irg_walk_func *) collect_irgs, NULL, irg_set);
161 interprocedural_view = true;
162 visited = get_max_irg_visited() + 1;
163 for (irg = eset_first(irg_set); irg; irg = eset_next(irg_set)) {
164 set_irg_visited(irg, visited);
166 irg_walk_cg(node, visited, irg_set, pre, post, env);
167 eset_destroy(irg_set);
169 inc_irg_visited(current_ir_graph);
170 irg_walk_2(node, pre, post, env);
176 void irg_walk_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
177 ir_graph * rem = current_ir_graph;
179 stat_irg_walk(irg, (void *)pre, (void *)post);
180 current_ir_graph = irg;
181 irg_walk(get_irg_end(irg), pre, post, env);
182 current_ir_graph = rem;
185 /* Executes irg_walk(end, pre, post, env) for all irgraphs in irprog.
186 Sets current_ir_graph properly for each walk. Conserves current
188 void all_irg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
192 rem = current_ir_graph;
194 for (i = 0; i < get_irp_n_irgs(); i++) {
195 irg = get_irp_irg(i);
196 current_ir_graph = irg;
197 irg_walk(get_irg_end(irg), pre, post, env);
199 current_ir_graph = rem;
202 /***************************************************************************/
204 /* Returns current_ir_graph and sets it to the irg of predecessor index
206 static INLINE ir_graph *
207 switch_irg (ir_node *n, int index) {
208 ir_graph *old_current = current_ir_graph;
210 if (interprocedural_view) {
211 /* Only Filter and Block nodes can have predecessors in other graphs. */
212 if (intern_get_irn_op(n) == op_Filter)
213 n = get_nodes_block(n);
214 if (intern_get_irn_op(n) == op_Block) {
215 ir_node *cfop = skip_Proj(get_Block_cfgpred(n, index));
216 if (is_ip_cfop(cfop)) {
217 current_ir_graph = get_irn_irg(cfop);
226 cg_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void * env)
229 ir_graph *rem = NULL;
232 if (get_irn_visited(node) < get_irg_visited(current_ir_graph)) {
233 set_irn_visited(node, get_irg_visited(current_ir_graph));
235 if (pre) pre(node, env);
237 if (is_no_Block(node))
238 cg_walk_2(get_nodes_block(node), pre, post, env);
239 for (i = intern_get_irn_arity(node) - 1; i >= 0; --i) {
240 rem = switch_irg(node, i); /* @@@ AS: Is this wrong? We do have to
241 switch to the irg of the predecessor, don't we? */
242 cg_walk_2(intern_get_irn_n(node, i), pre, post, env);
243 current_ir_graph = rem;
246 if (post) post(node, env);
252 /* Walks all irgs in interprocedural view. Visits each node only once. */
253 void cg_walk(irg_walk_func *pre, irg_walk_func *post, void *env) {
255 ir_graph *rem = current_ir_graph;
256 int rem_view = interprocedural_view;
258 interprocedural_view = true;
260 inc_max_irg_visited();
261 /* Fix all irg_visited flags */
262 for (i = 0; i < get_irp_n_irgs(); i++)
263 set_irg_visited(get_irp_irg(i), get_max_irg_visited());
265 /* Walk starting at unreachable procedures. Only these
266 * have End blocks visible in interprocedural view. */
267 for (i = 0; i < get_irp_n_irgs(); i++) {
269 current_ir_graph = get_irp_irg(i);
271 sb = get_irg_start_block(current_ir_graph);
273 if ((get_Block_n_cfgpreds(sb) > 1) ||
274 (get_nodes_block(get_Block_cfgpred(sb, 0)) != sb)) continue;
276 cg_walk_2(get_irg_end(current_ir_graph), pre, post, env);
279 /* Check whether we walked all procedures: there could be procedures
280 with cyclic calls but no call from the outside. */
281 for (i = 0; i < get_irp_n_irgs(); i++) {
283 current_ir_graph = get_irp_irg(i);
285 /* Test start block: if inner procedure end and end block are not
286 * visible and therefore not marked. */
287 sb = get_irg_start_block(current_ir_graph);
288 if (get_irn_visited(sb) < get_irg_visited(current_ir_graph)) {
289 cg_walk_2(sb, pre, post, env);
293 /* Walk all endless loops in inner procedures.
294 * We recognize an inner procedure if the End node is not visited. */
295 for (i = 0; i < get_irp_n_irgs(); i++) {
297 current_ir_graph = get_irp_irg(i);
298 e = get_irg_end(current_ir_graph);
299 if (get_irn_visited(e) < get_irg_visited(current_ir_graph)) {
301 /* Don't visit the End node. */
302 for (j = 0; j < get_End_n_keepalives(e); j++)
303 cg_walk_2(get_End_keepalive(e, j), pre, post, env);
307 interprocedural_view = rem_view;
308 current_ir_graph = rem;
312 /***************************************************************************/
314 /* Walks back from n until it finds a real cf op. */
315 static ir_node *get_cf_op(ir_node *n) {
321 if (!(is_cfop(pred) || is_fragile_op(pred) ||
322 (intern_get_irn_op(pred) == op_Bad)))
328 static void irg_block_walk_2(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
332 if(get_Block_block_visited(node) < get_irg_block_visited(current_ir_graph)) {
333 set_Block_block_visited(node, get_irg_block_visited(current_ir_graph));
335 if(pre) pre(node, env);
337 for(i = get_Block_n_cfgpreds(node) - 1; i >= 0; --i) {
338 /* find the corresponding predecessor block. */
339 ir_node *pred = get_cf_op(get_Block_cfgpred(node, i));
340 pred = get_nodes_block(pred);
341 if(intern_get_irn_opcode(pred) == iro_Block) {
343 irg_block_walk_2(pred, pre, post, env);
346 assert(get_irn_opcode(pred) == iro_Bad);
350 if(post) post(node, env);
356 /* walks only over Block nodes in the graph. Has it's own visited
357 flag, so that it can be interleaved with the other walker. */
358 void irg_block_walk(ir_node *node, irg_walk_func *pre, irg_walk_func *post, void *env)
360 ir_node *block, *pred;
363 stat_irg_block_walk(current_ir_graph, node, (void *)pre, (void *)post);
366 assert(!interprocedural_view); /* interprocedural_view not implemented, because it
367 * interleaves with irg_walk */
368 inc_irg_block_visited(current_ir_graph);
369 if (is_no_Block(node)) block = get_nodes_block(node); else block = node;
370 assert(get_irn_opcode(block) == iro_Block);
371 irg_block_walk_2(block, pre, post, env);
372 /* keepalive: the endless loops ... */
373 if (intern_get_irn_op(node) == op_End) {
374 int arity = intern_get_irn_arity(node);
375 for (i = 0; i < arity; i++) {
376 pred = intern_get_irn_n(node, i);
377 if (intern_get_irn_op(pred) == op_Block)
378 irg_block_walk_2(pred, pre, post, env);
386 void irg_block_walk_graph(ir_graph *irg, irg_walk_func *pre,
387 irg_walk_func *post, void *env) {
388 ir_graph * rem = current_ir_graph;
389 current_ir_graph = irg;
390 irg_block_walk(get_irg_end(irg), pre, post, env);
391 current_ir_graph = rem;
394 /********************************************************************/
396 typedef struct walk_env {
402 /* Walk to all constant expressions in this entity. */
403 static void walk_entity(entity *ent, void *env)
405 walk_env *my_env = (walk_env *)env;
407 if (get_entity_variability(ent) != variability_uninitialized) {
408 if (is_atomic_entity(ent)) {
409 irg_walk(get_atomic_ent_value(ent), my_env->pre, my_env->post, my_env->env);
412 int i, n = get_compound_ent_n_values(ent);
414 for (i = 0; i < n; i++)
415 irg_walk(get_compound_ent_value(ent, i), my_env->pre, my_env->post, my_env->env);
420 /* Walks over all code in const_code_irg. */
421 void walk_const_code(irg_walk_func *pre, irg_walk_func *post, void *env) {
425 ir_graph *rem = current_ir_graph;
426 current_ir_graph = get_const_code_irg();
427 inc_irg_visited(current_ir_graph);
433 /* Walk all types that can contain constant entities. */
434 walk_types_entities(get_glob_type(), &walk_entity, &my_env);
435 for (i = 0; i < get_irp_n_types(); i++)
436 walk_types_entities(get_irp_type(i), &walk_entity, &my_env);
437 for (i = 0; i < get_irp_n_irgs(); i++)
438 walk_types_entities(get_irg_frame_type(get_irp_irg(i)), &walk_entity, &my_env);
440 /* Walk constant array bounds. */
441 for (i = 0; i < get_irp_n_types(); i++) {
442 type *tp = get_irp_type(i);
443 if (is_array_type(tp)) {
444 for (j = 0; j < get_array_n_dimensions(tp); j++) {
446 n = get_array_lower_bound(tp, j);
447 if (n) irg_walk(n, pre, post, env);
448 n = get_array_upper_bound(tp, j);
449 if (n) irg_walk(n, pre, post, env);
454 current_ir_graph = rem;
458 /********************************************************************/
459 /** Walking support for interprocedural analysis **/
461 /** @@@ Don't use, not operational yet, doesn't grok recursions!! **/
462 /** @@@ Header for irgwalk.h, here until it works. **/
464 /** Interprocedural walking should not walk all predecessors of **/
465 /** all nodes. When leaving a procedure the walker should only **/
466 /** follow the edge corresponding to the most recent entry of the **/
467 /** procedure. The following functions use an internal stack to **/
468 /** remember the current call site of a procedure. **/
469 /** They also set current_ir_graph correctly. **/
471 /** Usage example: **/
473 /** void init_ip_walk (); **/
474 /** work_on_graph(some_end_node); **/
475 /** void finish_ip_walk(); **/
477 /** work_on_graph(ir_node *n) { **/
478 /** for (i = 0; i < get_irn_arity(n); i++) { **/
479 /** if (...) continue; **/
480 /** ir_node *m = get_irn_ip_pred(n, i); **/
481 /** if !m continue; **/
482 /** work_on_graph(m); **/
483 /** return_recur(n, i); **/
486 /********************************************************************/
488 /* Call for i in {0|-1 ... get_irn_arity(n)}.
489 If n is a conventional node returns the same node as get_irn_n(n, i).
490 If the predecessors of n are in the callee of the procedure n belongs
491 to, returns get_irn_n(n, i) if this node is in the callee on the top
492 of the stack, else returns NULL.
493 If the predecessors of n are in a procedure called by the procedure n
494 belongs to pushes the caller on the caller stack in the callee.
495 Sets current_ir_graph to the graph the node returned is in. */
496 ir_node *get_irn_ip_pred(ir_node *n, int pos);
498 /* If get_irn_ip_pred() returned a node (not NULL) this must be
499 called to clear up the stacks.
500 Sets current_ir_graph to the graph n is in. */
501 void return_recur(ir_node *n, int pos);
504 /********************************************************************/
505 /** Walking support for interprocedural analysis **/
506 /********************************************************************/
508 #define MIN_STACK_SIZE 40
510 typedef struct callsite_stack {
515 /* Access the stack in the irg **************************************/
518 set_irg_callsite_stack(ir_graph *g, callsite_stack *s) {
522 static INLINE callsite_stack *
523 get_irg_callsite_stack(ir_graph *g) {
524 return (callsite_stack *) get_irg_link(g);
527 /* A stack of callsites *********************************************/
529 /* @@@ eventually change the implementation so the new_ only sets the field
530 to NULL, and the stack is only allocated if used. Saves Memory! */
531 static INLINE callsite_stack *
532 new_callsite_stack(ir_graph *g) {
533 callsite_stack *res = (callsite_stack *)malloc(sizeof(callsite_stack));
535 res->s = NEW_ARR_F (ir_node *, MIN_STACK_SIZE);
536 set_irg_callsite_stack(g, res);
541 free_callsite_stack(ir_graph *g) {
542 callsite_stack *s = get_irg_callsite_stack(g);
548 push_callsite(ir_graph *callee, ir_node *callsite) {
549 callsite_stack *s = get_irg_callsite_stack(callee);
550 if (s->tos == ARR_LEN(s->s)) {
551 int nlen = ARR_LEN (s->s) * 2;
552 ARR_RESIZE (ir_node *, s->s, nlen);
554 s->s[s->tos] = callsite;
558 static INLINE ir_node *
559 get_top_of_callsite_stack(ir_graph *callee) {
560 callsite_stack *s = get_irg_callsite_stack(callee);
561 return (s->s[s->tos-1]);
565 ir_node * pop_callsite(ir_graph *callee) {
566 callsite_stack *s = get_irg_callsite_stack(callee);
568 return (s->s[s->tos]);
572 /* Initialization routines ******************************************/
574 void init_ip_walk (void) {
576 for (i = 0; i < get_irp_n_irgs(); i++)
577 new_callsite_stack(get_irp_irg(i));
580 void finish_ip_walk(void) {
582 for (i = 0; i < get_irp_n_irgs(); i++)
583 free_callsite_stack(get_irp_irg(i));
584 set_irg_link(get_irp_irg(i), NULL);
587 /* walker routines **************************************************/
589 /* cf_pred is End* */
591 enter_procedure(ir_node *block, ir_node *cf_pred, int pos) {
593 ir_graph *irg = get_irn_irg(cf_pred);
595 assert(interprocedural_view);
597 interprocedural_view = 0;
598 callbegin = skip_Proj(intern_get_irn_n(block, 0));
599 assert(intern_get_irn_op(callbegin) == op_CallBegin);
600 interprocedural_view = 1;
602 push_callsite(irg, callbegin);
603 current_ir_graph = irg;
606 /* cf_pred is CallBegin */
608 leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
609 ir_node *tos = get_top_of_callsite_stack(current_ir_graph);
611 assert(get_irn_op(cf_pred) == op_CallBegin);
613 if (tos == cf_pred) {
614 /* We entered this procedure by the call pred pos refers to. */
615 pop_callsite(current_ir_graph);
616 current_ir_graph = get_CallBegin_irg(cf_pred);
624 ir_node *get_irn_ip_pred(ir_node *n, int pos) {
626 if (interprocedural_view) {
628 /* Find the cf_pred refering to pos. */
631 if (intern_get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
632 cf_pred = skip_Proj(intern_get_irn_n(block, pos));
634 /* Check whether we enter or leave a procedure and act according. */
635 if ((intern_get_irn_op(cf_pred) == op_EndReg) ||
636 (intern_get_irn_op(cf_pred) == op_EndExcept))
637 enter_procedure(block, cf_pred, pos);
638 if (intern_get_irn_op(cf_pred) == op_CallBegin)
639 if (!leave_procedure(block, cf_pred, pos)) return NULL;
642 return intern_get_irn_n(n, pos);
646 re_enter_procedure(ir_node *block, ir_node *cf_pred, int pos) {
647 ir_node *callbegin = pop_callsite(current_ir_graph);
648 assert(interprocedural_view);
649 current_ir_graph = get_CallBegin_irg(callbegin);
653 re_leave_procedure(ir_node *block, ir_node *cf_pred, int pos) {
657 assert(get_irn_op(cf_pred) == op_CallBegin);
659 /* Find the irg block is in. */
660 proj = get_Block_cg_cfgpred(block, pos);
661 assert(is_Proj(proj));
662 callee = get_entity_irg(get_Call_callee(get_CallBegin_call(cf_pred),
663 get_Proj_proj(proj)));
664 current_ir_graph = callee;
665 push_callsite(callee, cf_pred);
669 return_recur(ir_node *n, int pos) {
673 if (!interprocedural_view) return;
675 /* Find the cf_pred refering to pos. */
677 if (intern_get_irn_opcode(n) == iro_Filter) block = get_nodes_block(n);
678 cf_pred = skip_Proj(intern_get_irn_n(block, pos));
680 /* Check whether we re_enter or re_leave a procedure and act according. */
681 if ((intern_get_irn_op(cf_pred) == op_EndReg) ||
682 (intern_get_irn_op(cf_pred) == op_EndExcept))
683 re_enter_procedure(block, cf_pred, pos);
684 if (intern_get_irn_op(cf_pred) == op_CallBegin)
685 re_leave_procedure(block, cf_pred, pos);