d6b4c7e5dbae8c98af4617c25210c8473da6c2f7
[libfirm] / ir / ir / iredges.c
1 /*
2  * Copyright (C) 1995-2011 University of Karlsruhe.  All right reserved.
3  *
4  * This file is part of libFirm.
5  *
6  * This file may be distributed and/or modified under the terms of the
7  * GNU General Public License version 2 as published by the Free Software
8  * Foundation and appearing in the file LICENSE.GPL included in the
9  * packaging of this file.
10  *
11  * Licensees holding valid libFirm Professional Edition licenses may use
12  * this file in accordance with the libFirm Commercial License.
13  * Agreement provided with the Software.
14  *
15  * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16  * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17  * PURPOSE.
18  */
19
20 /**
21  * @file
22  * @brief   Always available outs.
23  * @author  Sebastian Hack, Michael Beck, Andreas Schoesser
24  * @date    14.1.2005
25  * @brief
26  *   This are out-edges (also called def-use edges) that are dynamically
27  *   updated as the graph changes.
28  */
29 #include "config.h"
30
31 #include "irnode_t.h"
32 #include "iropt_t.h"
33 #include "iredgekinds.h"
34 #include "iredges_t.h"
35 #include "irgwalk.h"
36 #include "irdump_t.h"
37 #include "irprintf.h"
38 #include "debug.h"
39 #include "set.h"
40 #include "bitset.h"
41 #include "error.h"
42 #include "irpass_t.h"
43
44 #include "iredgeset.h"
45 #include "hashptr.h"
46
47 #define DO_REHASH
48 #define SCALAR_RETURN
49 #define HashSet                   ir_edgeset_t
50 #define HashSetIterator           ir_edgeset_iterator_t
51 #define ValueType                 ir_edge_t*
52 #define NullValue                 NULL
53 #define DeletedValue              ((ir_edge_t*)-1)
54 #define Hash(this,key)            (hash_ptr(key->src) ^ (key->pos * 40013))
55 #define KeysEqual(this,key1,key2) ((key1->src) == (key2->src) && (key1->pos == key2->pos))
56 #define SetRangeEmpty(ptr,size)   memset(ptr, 0, (size) * sizeof((ptr)[0]))
57
58 #define hashset_init            ir_edgeset_init
59 void ir_edgeset_init_size(ir_edgeset_t *self, size_t size);
60 #define hashset_init_size       ir_edgeset_init_size
61 #define hashset_destroy         ir_edgeset_destroy
62 #define hashset_insert          ir_edgeset_insert
63 #define hashset_remove          ir_edgeset_remove
64 ir_edge_t *ir_edgeset_find(const ir_edgeset_t *self, const ir_edge_t*);
65 #define hashset_find            ir_edgeset_find
66 size_t ir_edgeset_size(const ir_edgeset_t *self);
67 #define hashset_size            ir_edgeset_size
68 #define hashset_iterator_init   ir_edgeset_iterator_init
69 #define hashset_iterator_next   ir_edgeset_iterator_next
70 #define hashset_remove_iterator ir_edgeset_remove_iterator
71
72 #include "hashset.c.inl"
73
74 /**
75  * A function that allows for setting an edge.
76  * This abstraction is necessary since different edge kind have
77  * different methods of setting edges.
78  */
79 typedef void (set_edge_func_t)(ir_node *src, int pos, ir_node *tgt);
80
81 /**
82  * A function that returns the "arity" of a given edge kind
83  * for a node.
84  */
85 typedef int (get_edge_src_arity_func_t)(const ir_node *src);
86
87 /**
88  * A function that returns the pos'th edge of a given edge kind for a node.
89  */
90 typedef ir_node *(get_edge_src_n_func_t)(const ir_node *src, int pos);
91
92 /**
93  * Additional data for an edge kind.
94  */
95 typedef struct {
96         const char                *name;       /**< name of this edge kind */
97         set_edge_func_t           *set_edge;   /**< the set_edge function */
98         int                       first_idx;   /**< index of the first possible edge */
99         get_edge_src_arity_func_t *get_arity;  /**< the get_arity function */
100         get_edge_src_n_func_t     *get_n;      /**< the get_n function */
101 } ir_edge_kind_info_t;
102
103 /**
104  * Get the predecessor block.
105  */
106 static ir_node *get_block_n(const ir_node *block, int pos)
107 {
108         if (is_Block(block))
109                 return get_Block_cfgpred_block(block, pos);
110         /* might be a Bad */
111         return NULL;
112 }
113
114 static ir_node *get_irn_safe_n(const ir_node *node, int n)
115 {
116         if (n == -1 && is_Block(node))
117                 return NULL;
118         return get_irn_n(node, n);
119 }
120
121 static const ir_edge_kind_info_t edge_kind_info[EDGE_KIND_LAST] = {
122         { "normal"     , set_irn_n,   -1, get_irn_arity,  get_irn_safe_n },
123         { "block succs", NULL,         0, get_irn_arity,  get_block_n    },
124         { "dependency",  set_irn_dep,  0, get_irn_deps,   get_irn_dep    }
125 };
126
127 #define foreach_tgt(irn, i, n, kind) for (i = edge_kind_info[kind].first_idx, n = edge_kind_info[kind].get_arity(irn); i < n; ++i)
128 #define get_n(irn, pos, kind)        (edge_kind_info[kind].get_n(irn, pos))
129 #define get_kind_str(kind)           (edge_kind_info[kind].name)
130
131 DEBUG_ONLY(static firm_dbg_module_t *dbg;)
132
133 /**
134  * This flag is set to 1, if the edges get initialized for an irg.
135  * Then register additional data is forbidden.
136  */
137 static int edges_used = 0;
138
139 /**
140  * If set to 1, the list heads are checked every time an edge is changed.
141  */
142 static int edges_dbg = 0;
143
144 /**
145  * Returns an ID for the given edge.
146  */
147 static inline long edge_get_id(const ir_edge_t *e)
148 {
149         return (long)e;
150 }
151
152 void edges_init_graph_kind(ir_graph *irg, ir_edge_kind_t kind)
153 {
154         if (edges_activated_kind(irg, kind)) {
155                 irg_edge_info_t *info = get_irg_edge_info(irg, kind);
156                 size_t amount = get_irg_last_idx(irg) * 5 / 4;
157
158                 edges_used = 1;
159                 if (info->allocated) {
160                         amount = ir_edgeset_size(&info->edges);
161                         ir_edgeset_destroy(&info->edges);
162                         obstack_free(&info->edges_obst, NULL);
163                 }
164                 obstack_init(&info->edges_obst);
165                 INIT_LIST_HEAD(&info->free_edges);
166                 ir_edgeset_init_size(&info->edges, amount);
167                 info->allocated = 1;
168         }
169 }
170
171 const ir_edge_t *get_irn_edge_kind(const ir_node *src, int pos, ir_edge_kind_t kind)
172 {
173         ir_graph *irg = get_irn_irg(src);
174         if (edges_activated_kind(irg, kind)) {
175                 irg_edge_info_t *info = get_irg_edge_info(irg, kind);
176                 ir_edge_t       key;
177
178                 key.src = (ir_node *)src;
179                 key.pos = pos;
180
181                 return ir_edgeset_find(&info->edges, &key);
182         }
183
184         return NULL;
185 }
186
187 /**
188  * Change the out count
189  *
190  * @param tgt  the edge target
191  * @param kind the kind of the edge
192  */
193 static inline void edge_change_cnt(ir_node *tgt, ir_edge_kind_t kind, int ofs)
194 {
195         irn_edge_info_t *info = get_irn_edge_info(tgt, kind);
196         info->out_count += ofs;
197 }
198
199 /**
200  * Verify the edge list of a node, ie. ensure it's a loop:
201  * head -> e_1 -> ... -> e_n -> head
202  */
203 static inline void verify_list_head(ir_node *irn, ir_edge_kind_t kind)
204 {
205         int                    err     = 0;
206         int                    num     = 0;
207         pset                   *lh_set = pset_new_ptr(16);
208         const struct list_head *head   = &get_irn_edge_info(irn, kind)->outs_head;
209         const struct list_head *pos;
210
211         list_for_each(pos, head) {
212                 if (pset_find_ptr(lh_set, pos)) {
213                         const ir_edge_t *edge = list_entry(pos, ir_edge_t, list);
214
215                         ir_fprintf(stderr, "EDGE Verifier: edge list broken (self loop not to head) for %+F:\n", irn);
216                         fprintf(stderr, "- at list entry %d\n", num);
217                         if (edge->invalid)
218                                 fprintf(stderr, "- edge(%ld) is invalid\n", edge_get_id(edge));
219                         if (edge->src)
220                                 ir_fprintf(stderr, "- edge(%ld) %+F(%d)\n", edge_get_id(edge), edge->src, edge->pos);
221                         err = 1;
222                         break;
223                 }
224                 num++;
225                 pset_insert_ptr(lh_set, pos);
226         }
227
228         del_pset(lh_set);
229
230         assert(err == 0);
231 }
232
233 void edges_dump_kind(ir_graph *irg, ir_edge_kind_t kind)
234 {
235         irg_edge_info_t *info;
236         ir_edgeset_t    *edges;
237         ir_edgeset_iterator_t iter;
238         ir_edge_t      *e;
239
240         if (!edges_activated_kind(irg, kind))
241                 return;
242
243         info  = get_irg_edge_info(irg, kind);
244         edges = &info->edges;
245         foreach_ir_edgeset(edges, e, iter) {
246                 ir_printf("%+F %d %d\n", e->src, e->pos, e->invalid);
247         }
248 }
249
250 void edges_notify_edge_kind(ir_node *src, int pos, ir_node *tgt,
251                             ir_node *old_tgt, ir_edge_kind_t kind,
252                             ir_graph *irg)
253 {
254         const char      *msg = "";
255         irg_edge_info_t *info;
256         ir_edgeset_t    *edges;
257         ir_edge_t        templ;
258
259         assert(edges_activated_kind(irg, kind));
260
261         /*
262          * Only do something, if the old and new target differ.
263          */
264         if (tgt == old_tgt)
265                 return;
266
267         info  = get_irg_edge_info(irg, kind);
268         edges = &info->edges;
269
270         /* Initialize the edge template to search in the set. */
271         templ.src = src;
272         templ.pos = pos;
273
274         /*
275          * If the target is NULL, the edge shall be deleted.
276          */
277         if (tgt == NULL) {
278                 /* search the edge in the set. */
279                 ir_edge_t *edge = ir_edgeset_find(edges, &templ);
280
281                 /* mark the edge invalid if it was found */
282                 if (edge) {
283                         msg = "deleting";
284                         list_del(&edge->list);
285                         ir_edgeset_remove(edges, edge);
286                         list_add(&edge->list, &info->free_edges);
287                         edge->invalid = 1;
288                         edge->pos = -2;
289                         edge->src = NULL;
290                         edge_change_cnt(old_tgt, kind, -1);
291                 } else {
292                         /* If the edge was not found issue a warning on the debug stream */
293                         msg = "edge to delete not found!\n";
294                 }
295         } else {
296                 /*
297                  * The target is not NULL and the old target differs
298                  * from the new target, the edge shall be moved (if the
299                  * old target was != NULL) or added (if the old target was
300                  * NULL).
301                  */
302                 struct list_head *head = &get_irn_edge_info(tgt, kind)->outs_head;
303
304                 assert(head->next && head->prev &&
305                                 "target list head must have been initialized");
306
307                 /* If the old target is not null, the edge is moved. */
308                 if (old_tgt) {
309                         ir_edge_t *edge = ir_edgeset_find(edges, &templ);
310                         assert(edge && "edge to redirect not found!");
311                         assert(! edge->invalid && "Invalid edge encountered");
312
313                         msg = "redirecting";
314
315                         list_move(&edge->list, head);
316                         edge_change_cnt(old_tgt, kind, -1);
317                 } else {
318                         /* The old target was NULL, thus, the edge is newly created. */
319                         ir_edge_t *new_edge;
320                         ir_edge_t *edge;
321
322                         if (list_empty(&info->free_edges)) {
323                                 edge = OALLOC(&info->edges_obst, ir_edge_t);
324                         } else {
325                                 edge = list_entry(info->free_edges.next, ir_edge_t, list);
326                                 list_del(&edge->list);
327                         }
328
329                         edge->src       = src;
330                         edge->pos       = pos;
331                         edge->invalid   = 0;
332                         edge->present   = 0;
333                         edge->kind      = kind;
334                         edge->list.next = NULL;
335                         edge->list.prev = NULL;
336
337                         new_edge = ir_edgeset_insert(edges, edge);
338                         if (new_edge != edge) {
339                                 panic("new edge exists already");
340                         }
341
342                         msg = "adding";
343                         list_add(&edge->list, head);
344                 }
345
346                 edge_change_cnt(tgt, kind, +1);
347         }
348
349 #ifndef DEBUG_libfirm
350         /* verify list heads */
351         if (edges_dbg) {
352                 if (tgt)
353                         verify_list_head(tgt, kind);
354                 if (old_tgt)
355                         verify_list_head(old_tgt, kind);
356         }
357 #endif
358
359         DBG((dbg, LEVEL_5, "announce out edge: %+F %d-> %+F(%+F): %s\n", src, pos, tgt, old_tgt, msg));
360 }
361
362 void edges_notify_edge(ir_node *src, int pos, ir_node *tgt, ir_node *old_tgt,
363                        ir_graph *irg)
364 {
365         if (edges_activated_kind(irg, EDGE_KIND_NORMAL)) {
366                 edges_notify_edge_kind(src, pos, tgt, old_tgt, EDGE_KIND_NORMAL, irg);
367         }
368
369         if (edges_activated_kind(irg, EDGE_KIND_BLOCK)) {
370                 if (is_Block(src)) {
371                         ir_node *bl_old = old_tgt ? get_nodes_block(old_tgt) : NULL;
372                         ir_node *bl_tgt = NULL;
373
374                         if (tgt)
375                                 bl_tgt = is_Bad(tgt) ? tgt : get_nodes_block(tgt);
376
377                         edges_notify_edge_kind(src, pos, bl_tgt, bl_old, EDGE_KIND_BLOCK, irg);
378                 } else if (get_irn_mode(src) == mode_X && old_tgt != NULL && is_Block(old_tgt)) {
379                         /* moving a jump node from one block to another */
380                         foreach_out_edge_kind_safe(old_tgt, edge, EDGE_KIND_BLOCK) {
381                                 ir_node *succ       = get_edge_src_irn(edge);
382                                 int      succ_pos   = get_edge_src_pos(edge);
383                                 ir_node *block_pred = get_Block_cfgpred(succ, succ_pos);
384                                 if (block_pred != src)
385                                         continue;
386                                 edges_notify_edge_kind(succ, succ_pos, tgt, old_tgt,
387                                                        EDGE_KIND_BLOCK, irg);
388                         }
389                 }
390         }
391 }
392
393 /**
394  * Delete all in edges of a given kind from the node old.
395  *
396  * @param old   the node
397  * @param kind  the kind of edges to remove
398  * @param irg   the irg of the old node
399  */
400 static void edges_node_deleted_kind(ir_node *old, ir_edge_kind_t kind)
401 {
402         int i, n;
403         ir_graph *irg = get_irn_irg(old);
404
405         if (!edges_activated_kind(irg, kind))
406                 return;
407
408         DBG((dbg, LEVEL_5, "node deleted (kind: %s): %+F\n", get_kind_str(kind), old));
409
410         foreach_tgt(old, i, n, kind) {
411                 ir_node *old_tgt = get_n(old, i, kind);
412                 edges_notify_edge_kind(old, i, NULL, old_tgt, kind, irg);
413         }
414 }
415
416 /**
417  * A node might be revivaled by CSE. Assure its edges.
418  *
419  * @param irn   the node
420  * @param kind  the kind of edges to remove
421  * @param irg   the irg of the old node
422  */
423 static void edges_node_revival_kind(ir_node *irn, ir_edge_kind_t kind)
424 {
425         irn_edge_info_t *info;
426         int             i, n;
427         ir_graph        *irg = get_irn_irg(irn);
428
429         if (!edges_activated_kind(irg, kind))
430                 return;
431
432         info = get_irn_edge_info(irn, kind);
433         if (info->edges_built)
434                 return;
435
436         DBG((dbg, LEVEL_5, "node revivaled (kind: %s): %+F\n", get_kind_str(kind), irn));
437
438         foreach_tgt(irn, i, n, kind) {
439                 ir_node *tgt = get_n(irn, i, kind);
440                 edges_notify_edge_kind(irn, i, tgt, NULL, kind, irg);
441         }
442         info->edges_built = 1;
443 }
444
445 typedef struct build_walker {
446         ir_edge_kind_t kind;
447         bitset_t       *reachable;
448         unsigned       problem_found;
449 } build_walker;
450
451 /**
452  * Post-Walker: notify all edges
453  */
454 static void build_edges_walker(ir_node *irn, void *data)
455 {
456         build_walker          *w = (build_walker*)data;
457         int                   i, n;
458         ir_edge_kind_t        kind = w->kind;
459         ir_graph              *irg = get_irn_irg(irn);
460
461         foreach_tgt(irn, i, n, kind) {
462                 ir_node *pred = get_n(irn, i, kind);
463                 edges_notify_edge_kind(irn, i, pred, NULL, kind, irg);
464         }
465         get_irn_edge_info(irn, kind)->edges_built = 1;
466 }
467
468 /**
469  * Pre-Walker: initializes the list-heads and set the out-count
470  * of all nodes to 0.
471  */
472 static void init_lh_walker(ir_node *irn, void *data)
473 {
474         build_walker   *w    = (build_walker*)data;
475         ir_edge_kind_t  kind = w->kind;
476         list_head      *head = &get_irn_edge_info(irn, kind)->outs_head;
477         INIT_LIST_HEAD(head);
478         get_irn_edge_info(irn, kind)->edges_built = 0;
479         get_irn_edge_info(irn, kind)->out_count   = 0;
480 }
481
482 /**
483  * Pre-Walker: initializes the list-heads and set the out-count
484  * of all nodes to 0.
485  *
486  * Additionally touches DEP nodes, as they might be DEAD.
487  * THIS IS UGLY, but I don't find a better way until we
488  *
489  * a) ensure that dead nodes are not used as input
490  * b) it might be sufficient to add those stupid NO_REG nodes
491  * to the anchor
492  */
493 static void init_lh_walker_dep(ir_node *irn, void *data)
494 {
495         build_walker   *w    = (build_walker*)data;
496         ir_edge_kind_t  kind = w->kind;
497         list_head      *head = &get_irn_edge_info(irn, kind)->outs_head;
498         int             i;
499
500         INIT_LIST_HEAD(head);
501         get_irn_edge_info(irn, kind)->edges_built = 0;
502         get_irn_edge_info(irn, kind)->out_count   = 0;
503
504         for (i = get_irn_deps(irn) - 1; i >= 0; --i) {
505                 ir_node *dep = get_irn_dep(irn, i);
506
507                 head = &get_irn_edge_info(dep, kind)->outs_head;
508
509                 INIT_LIST_HEAD(head);
510                 get_irn_edge_info(dep, kind)->edges_built = 0;
511                 get_irn_edge_info(dep, kind)->out_count   = 0;
512         }
513 }
514
515 typedef struct visitor_info_t {
516         irg_walk_func *visit;
517         void *data;
518 } visitor_info_t;
519
520 /**
521  * Visitor: initializes the list-heads and set the out-count
522  * of all nodes to 0 of nodes that are not seen so far.
523  */
524 static void visitor(ir_node *irn, void *data)
525 {
526         visitor_info_t *info = (visitor_info_t*)data;
527
528         if (is_Deleted(irn))
529                 return;
530         if (!is_Block(irn) && is_Deleted(get_nodes_block(irn)))
531                 return;
532
533         if (!irn_visited_else_mark(irn)) {
534                 info->visit(irn, info->data);
535         }
536 }
537
538 void edges_activate_kind(ir_graph *irg, ir_edge_kind_t kind)
539 {
540         /*
541          * Build the initial edge set.
542          * Beware, this is not a simple task because it suffers from two
543          * difficulties:
544          * - the anchor set allows access to Nodes that may not be reachable from
545          *   the End node
546          * - the identities add nodes to the "root set" that are not yet reachable
547          *   from End. However, after some transformations, the CSE may revival these
548          *   nodes
549          *
550          * These problems can be fixed using different strategies:
551          * - Add an age flag to every node. Whenever the edge of a node is older
552          *   then the current edge, invalidate the edges of this node.
553          *   While this would help for revivaled nodes, it increases memory and runtime.
554          * - Delete the identities set.
555          *   Solves the revival problem, but may increase the memory consumption, as
556          *   nodes cannot be revivaled at all.
557          * - Manually iterate over the identities root set. This did not consume more memory
558          *   but increase the computation time because the |identities| >= |V|
559          *
560          * Currently, we use the last option.
561          */
562         struct build_walker w;
563         irg_edge_info_t     *info = get_irg_edge_info(irg, kind);
564         visitor_info_t      visit;
565
566         w.kind = kind;
567
568         visit.data = &w;
569
570         assert(!info->activated);
571
572         info->activated = 1;
573         edges_init_graph_kind(irg, kind);
574         if (kind == EDGE_KIND_DEP) {
575                 irg_walk_anchors(irg, init_lh_walker_dep, NULL, &w);
576                 /* Argh: Dep nodes might be dead, so we MUST visit identities first */
577                 visit.visit = init_lh_walker_dep;
578                 visit_all_identities(irg, visitor, &visit);
579                 irg_walk_anchors(irg, NULL, build_edges_walker, &w);
580         } else {
581                 visit.visit = init_lh_walker;
582                 visit_all_identities(irg, visitor, &visit);
583                 irg_walk_anchors(irg, init_lh_walker, build_edges_walker, &w);
584         }
585 }
586
587 void edges_deactivate_kind(ir_graph *irg, ir_edge_kind_t kind)
588 {
589         irg_edge_info_t *info = get_irg_edge_info(irg, kind);
590
591         info->activated = 0;
592         if (info->allocated) {
593                 obstack_free(&info->edges_obst, NULL);
594                 ir_edgeset_destroy(&info->edges);
595                 info->allocated = 0;
596         }
597         clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUT_EDGES);
598 }
599
600 int (edges_activated_kind)(const ir_graph *irg, ir_edge_kind_t kind)
601 {
602         return edges_activated_kind_(irg, kind);
603 }
604
605 int (edges_activated)(const ir_graph *irg)
606 {
607         return edges_activated_(irg);
608 }
609
610 void edges_reroute_kind(ir_node *from, ir_node *to, ir_edge_kind_t kind)
611 {
612         ir_graph *irg = get_irn_irg(from);
613         set_edge_func_t *set_edge = edge_kind_info[kind].set_edge;
614
615         if (set_edge && edges_activated_kind(irg, kind)) {
616                 struct list_head *head = &get_irn_edge_info(from, kind)->outs_head;
617
618                 DBG((dbg, LEVEL_5, "reroute from %+F to %+F\n", from, to));
619
620                 while (head != head->next) {
621                         ir_edge_t *edge = list_entry(head->next, ir_edge_t, list);
622                         assert(edge->pos >= -1);
623                         set_edge(edge->src, edge->pos, to);
624                 }
625         }
626 }
627
628 void edges_reroute(ir_node *from, ir_node *to)
629 {
630         edges_reroute_kind(from, to, EDGE_KIND_NORMAL);
631 }
632
633 void edges_reroute_except(ir_node *from, ir_node *to, ir_node *exception)
634 {
635         foreach_out_edge_safe(from, edge) {
636                 ir_node *src = get_edge_src_irn(edge);
637                 if (src == exception)
638                         continue;
639                 set_irn_n(src, edge->pos, to);
640         }
641 }
642
643 static void verify_set_presence(ir_node *irn, void *data)
644 {
645         build_walker *w     = (build_walker*)data;
646         ir_graph     *irg   = get_irn_irg(irn);
647         ir_edgeset_t *edges = &get_irg_edge_info(irg, w->kind)->edges;
648         int i, n;
649
650         foreach_tgt(irn, i, n, w->kind) {
651                 ir_edge_t templ, *e;
652
653                 templ.src = irn;
654                 templ.pos = i;
655
656                 e = ir_edgeset_find(edges, &templ);
657                 if (e != NULL) {
658                         e->present = 1;
659                 } else {
660                         w->problem_found = 1;
661                 }
662         }
663 }
664
665 static void verify_list_presence(ir_node *irn, void *data)
666 {
667         build_walker *w = (build_walker*)data;
668
669         bitset_set(w->reachable, get_irn_idx(irn));
670
671         /* check list heads */
672         verify_list_head(irn, w->kind);
673
674         foreach_out_edge_kind(irn, e, w->kind) {
675                 ir_node *tgt;
676
677                 if (w->kind == EDGE_KIND_NORMAL && get_irn_arity(e->src) <= e->pos) {
678                         w->problem_found = 1;
679                         continue;
680                 }
681
682                 tgt = get_n(e->src, e->pos, w->kind);
683
684                 if (irn != tgt) {
685                         w->problem_found = 1;
686                 }
687         }
688 }
689
690 int edges_verify_kind(ir_graph *irg, ir_edge_kind_t kind)
691 {
692         struct build_walker w;
693         ir_edgeset_t        *edges = &get_irg_edge_info(irg, kind)->edges;
694         ir_edge_t           *e;
695         ir_edgeset_iterator_t  iter;
696
697         w.kind          = kind;
698         w.reachable     = bitset_alloca(get_irg_last_idx(irg));
699         w.problem_found = 0;
700
701         /* Clear the present bit in all edges available. */
702         foreach_ir_edgeset(edges, e, iter) {
703                 e->present = 0;
704         }
705
706         irg_walk_graph(irg, verify_set_presence, verify_list_presence, &w);
707
708         /*
709          * Dump all edges which are not invalid and not present.
710          * These edges are superfluous and their presence in the
711          * edge set is wrong.
712          */
713         foreach_ir_edgeset(edges, e, iter) {
714                 if (! e->invalid && ! e->present && bitset_is_set(w.reachable, get_irn_idx(e->src))) {
715                         w.problem_found = 1;
716                         ir_fprintf(stderr, "Edge Verifier: edge(%ld) %+F,%d is superfluous\n", edge_get_id(e), e->src, e->pos);
717                 }
718         }
719
720         return w.problem_found;
721 }
722
723 #define IGNORE_NODE(irn) (is_Bad((irn)) || is_Block((irn)))
724
725 /**
726  * Clear link field of all nodes.
727  */
728 static void clear_links(ir_node *irn, void *env)
729 {
730         bitset_t     *bs;
731         ir_graph     *irg;
732         (void) env;
733
734         if (IGNORE_NODE(irn)) {
735                 set_irn_link(irn, NULL);
736                 return;
737         }
738
739         irg = get_irn_irg(irn);
740         bs  = bitset_malloc(get_irg_last_idx(irg));
741         set_irn_link(irn, bs);
742 }
743
744 /**
745  * Increases count (stored in link field) for all operands of a node.
746  */
747 static void count_user(ir_node *irn, void *env)
748 {
749         int i;
750         int first;
751         (void) env;
752
753         first = is_Block(irn) ? 0 : -1;
754         for (i = get_irn_arity(irn) - 1; i >= first; --i) {
755                 ir_node  *op = get_irn_n(irn, i);
756                 bitset_t *bs = (bitset_t*)get_irn_link(op);
757
758                 if (bs)
759                         bitset_set(bs, get_irn_idx(irn));
760         }
761 }
762
763 /**
764  * Verifies if collected count, number of edges in list and stored edge count are in sync.
765  */
766 static void verify_edge_counter(ir_node *irn, void *env)
767 {
768         build_walker *w = (build_walker*)env;
769         if (IGNORE_NODE(irn))
770                 return;
771
772         bitset_t *bs       = (bitset_t*)get_irn_link(irn);
773         int       list_cnt = 0;
774         int       edge_cnt = get_irn_edge_info(irn, EDGE_KIND_NORMAL)->out_count;
775         const struct list_head *head
776                 = &get_irn_edge_info(irn, EDGE_KIND_NORMAL)->outs_head;
777
778         /* We can iterate safely here, list heads have already been verified. */
779         const struct list_head *pos;
780         list_for_each(pos, head) {
781                 ++list_cnt;
782         }
783
784         /* check all nodes that reference us and count edges that point number
785          * of ins that actually point to us */
786         ir_graph *irg     = get_irn_irg(irn);
787         int       ref_cnt = 0;
788         bitset_foreach(bs, idx) {
789                 int i, arity;
790                 ir_node *src = get_idx_irn(irg, idx);
791
792                 arity = get_irn_arity(src);
793                 for (i = 0; i < arity; ++i) {
794                         ir_node *in = get_irn_n(src, i);
795                         if (in == irn)
796                                 ++ref_cnt;
797                 }
798         }
799
800         if (edge_cnt != list_cnt) {
801                 w->problem_found = 1;
802                 ir_fprintf(stderr, "Edge Verifier: edge count is %d, but %d edge(s) are recorded in list at %+F\n",
803                         edge_cnt, list_cnt, irn);
804         }
805
806         if (ref_cnt != list_cnt) {
807                 w->problem_found = 1;
808                 ir_fprintf(stderr, "Edge Verifier: %+F reachable by %d node(s), but the list contains %d edge(s)\n",
809                         irn, ref_cnt, list_cnt);
810         }
811
812         bitset_free(bs);
813 }
814
815 int edges_verify(ir_graph *irg)
816 {
817         struct build_walker w;
818         int    problem_found = 0;
819
820         /* verify normal edges only */
821         problem_found  = edges_verify_kind(irg, EDGE_KIND_NORMAL);
822
823         w.kind          = EDGE_KIND_NORMAL;
824         w.problem_found = 0;
825
826         /* verify counter */
827         irg_walk_anchors(irg, clear_links, count_user, &w);
828         irg_walk_anchors(irg, NULL, verify_edge_counter, &w);
829
830         return problem_found ? 1 : w.problem_found;
831 }
832
833 typedef struct pass_t {
834         ir_graph_pass_t pass;
835         unsigned        assert_on_problem;
836 } pass_t;
837
838 /**
839  * Wrapper to edges_verify to be run as an ir_graph pass.
840  */
841 static int edges_verify_wrapper(ir_graph *irg, void *context)
842 {
843         pass_t *pass           = (pass_t*)context;
844         int     problems_found = edges_verify(irg);
845         /* do NOT rerun the pass if verify is ok :-) */
846         assert(problems_found && pass->assert_on_problem);
847         return 0;
848 }
849
850 ir_graph_pass_t *irg_verify_edges_pass(const char *name, unsigned assert_on_problem)
851 {
852         pass_t *pass = XMALLOCZ(pass_t);
853
854         def_graph_pass_constructor(
855                 &pass->pass, name ? name : "edges_verify", edges_verify_wrapper);
856
857         /* neither dump nor verify */
858         pass->pass.dump_irg   = (DUMP_ON_IRG_FUNC)ir_prog_no_dump;
859         pass->pass.verify_irg = (RUN_ON_IRG_FUNC)ir_prog_no_verify;
860
861         pass->assert_on_problem = assert_on_problem;
862         return &pass->pass;
863 }
864
865 void init_edges(void)
866 {
867         FIRM_DBG_REGISTER(dbg, "firm.ir.edges");
868 }
869
870 void edges_init_dbg(int do_dbg)
871 {
872         edges_dbg = do_dbg;
873 }
874
875 void edges_activate(ir_graph *irg)
876 {
877         edges_activate_kind(irg, EDGE_KIND_NORMAL);
878         edges_activate_kind(irg, EDGE_KIND_BLOCK);
879         edges_activate_kind(irg, EDGE_KIND_DEP);
880 }
881
882 void edges_deactivate(ir_graph *irg)
883 {
884         edges_deactivate_kind(irg, EDGE_KIND_DEP);
885         edges_deactivate_kind(irg, EDGE_KIND_BLOCK);
886         edges_deactivate_kind(irg, EDGE_KIND_NORMAL);
887 }
888
889 void assure_edges(ir_graph *irg)
890 {
891         assure_edges_kind(irg, EDGE_KIND_BLOCK);
892         assure_edges_kind(irg, EDGE_KIND_NORMAL);
893         assure_edges_kind(irg, EDGE_KIND_DEP);
894         add_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUT_EDGES);
895 }
896
897 void assure_edges_kind(ir_graph *irg, ir_edge_kind_t kind)
898 {
899         if (!edges_activated_kind(irg, kind))
900                 edges_activate_kind(irg, kind);
901 }
902
903 void edges_node_deleted(ir_node *irn)
904 {
905         edges_node_deleted_kind(irn, EDGE_KIND_NORMAL);
906         edges_node_deleted_kind(irn, EDGE_KIND_BLOCK);
907         edges_node_deleted_kind(irn, EDGE_KIND_DEP);
908 }
909
910 void edges_node_revival(ir_node *irn)
911 {
912         edges_node_revival_kind(irn, EDGE_KIND_NORMAL);
913         edges_node_revival_kind(irn, EDGE_KIND_BLOCK);
914 }
915
916 const ir_edge_t *(get_irn_out_edge_first_kind)(const ir_node *irn, ir_edge_kind_t kind)
917 {
918         return get_irn_out_edge_first_kind_(irn, kind);
919 }
920
921 const ir_edge_t *(get_irn_out_edge_first)(const ir_node *irn)
922 {
923         return get_irn_out_edge_first_kind_(irn, EDGE_KIND_NORMAL);
924 }
925
926 const ir_edge_t *(get_block_succ_first)(const ir_node *block)
927 {
928         return get_irn_out_edge_first_kind_(block, EDGE_KIND_BLOCK);
929 }
930
931 const ir_edge_t *(get_irn_out_edge_next)(const ir_node *irn, const ir_edge_t *last)
932 {
933         return get_irn_out_edge_next_(irn, last);
934 }
935
936 ir_node *(get_edge_src_irn)(const ir_edge_t *edge)
937 {
938         return get_edge_src_irn_(edge);
939 }
940
941 int (get_edge_src_pos)(const ir_edge_t *edge)
942 {
943         return get_edge_src_pos_(edge);
944 }
945
946 int (get_irn_n_edges_kind)(const ir_node *irn, ir_edge_kind_t kind)
947 {
948         return get_irn_n_edges_kind_(irn, kind);
949 }
950
951 static void irg_walk_edges2(ir_node *node, irg_walk_func *pre,
952                             irg_walk_func *post, void *env)
953 {
954         if (irn_visited_else_mark(node))
955                 return;
956
957         if (pre != NULL)
958                 pre(node, env);
959
960         foreach_out_edge_kind_safe(node, edge, EDGE_KIND_NORMAL) {
961                 /* find the corresponding successor block. */
962                 ir_node *pred = get_edge_src_irn(edge);
963                 irg_walk_edges2(pred, pre, post, env);
964         }
965
966         if (post != NULL)
967                 post(node, env);
968 }
969
970 void irg_walk_edges(ir_node *node, irg_walk_func *pre, irg_walk_func *post,
971                     void *env)
972 {
973         ir_graph *irg = get_irn_irg(node);
974
975         assert(edges_activated(irg));
976         assert(is_Block(node));
977
978         ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
979
980         inc_irg_visited(irg);
981         irg_walk_edges2(node, pre, post, env);
982
983         ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
984 }
985
986 static void irg_block_edges_walk2(ir_node *bl, irg_walk_func *pre,
987                                   irg_walk_func *post, void *env)
988 {
989         if (!Block_block_visited(bl)) {
990                 mark_Block_block_visited(bl);
991
992                 if (pre)
993                         pre(bl, env);
994
995                 foreach_out_edge_kind_safe(bl, edge, EDGE_KIND_BLOCK) {
996                         /* find the corresponding successor block. */
997                         ir_node *pred = get_edge_src_irn(edge);
998                         irg_block_edges_walk2(pred, pre, post, env);
999                 }
1000
1001                 if (post)
1002                         post(bl, env);
1003         }
1004 }
1005
1006 void irg_block_edges_walk(ir_node *node, irg_walk_func *pre,
1007                           irg_walk_func *post, void *env)
1008 {
1009         ir_graph *irg = get_irn_irg(node);
1010
1011         assert(edges_activated(irg));
1012         assert(is_Block(node));
1013
1014         ir_reserve_resources(irg, IR_RESOURCE_BLOCK_VISITED);
1015
1016         inc_irg_block_visited(irg);
1017         irg_block_edges_walk2(node, pre, post, env);
1018
1019         ir_free_resources(irg, IR_RESOURCE_BLOCK_VISITED);
1020 }