3 * File name: ir/ir/iredges.c
4 * Purpose: Always available outs.
5 * Author: Sebastian Hack
6 * Modified by: Michael Beck
9 * Copyright: (c) 1998-2006 Universität Karlsruhe
10 * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
14 * Always available outs.
15 * @author Sebastian Hack
32 #include "iredges_t.h"
40 DEBUG_ONLY(static firm_dbg_module_t *dbg;)
43 * This flag is set to 1, if the edges get initialized for an irg.
44 * Then register additional data is forbidden.
46 static int edges_used = 0;
48 static int edges_private_size = 0;
50 int edges_register_private_data(size_t n)
52 int res = edges_private_size;
54 assert(!edges_used && "you cannot register private edge data, if edges have been initialized");
56 edges_private_size += n;
60 #define TIMES37(x) (((x) << 5) + ((x) << 2) + (x))
62 #define get_irn_out_list_head(irn) (&get_irn_out_info(irn)->outs)
64 static int edge_cmp(const void *p1, const void *p2, size_t len)
66 const ir_edge_t *e1 = p1;
67 const ir_edge_t *e2 = p2;
68 int res = e1->src == e2->src && e1->pos == e2->pos;
73 #define edge_hash(edge) (TIMES37((edge)->pos) + HASH_PTR((edge)->src))
76 * Initialize the out information for a graph.
77 * @note Dead node elimination can call this on an already initialized graph.
79 void edges_init_graph(ir_graph *irg)
81 if(edges_activated(irg)) {
82 irg_edge_info_t *info = _get_irg_edge_info(irg);
88 amount = set_count(info->edges);
92 info->edges = new_set(edge_cmp, amount);
96 #define EDGE_SIZE(src) \
97 (edges_private_size + (is_Block(src) ? sizeof(ir_block_edge_t) : sizeof(ir_edge_t)))
101 * Get the edge object of an outgoing edge at a node.
102 * @param irg The graph, the node is in.
103 * @param src The node at which the edge originates.
104 * @param pos The position of the edge.
105 * @return The corresponding edge object or NULL,
106 * if no such edge exists.
108 const ir_edge_t *get_irn_edge(ir_graph *irg, const ir_node *src, int pos)
110 if(edges_activated(irg)) {
111 irg_edge_info_t *info = _get_irg_edge_info(irg);
112 size_t size = EDGE_SIZE(src);
115 key.src = (ir_node *) src;
117 return set_find(info->edges, &key, size, edge_hash(&key));
124 * Change the out count
126 static INLINE void edge_change_cnt(ir_node *tgt, int ofs) {
127 irn_edge_info_t *info = _get_irn_edge_info(tgt);
128 info->out_count += ofs;
131 /* The edge from (src, pos) -> old_tgt is redirected to tgt */
132 void edges_notify_edge(ir_node *src, int pos, ir_node *tgt, ir_node *old_tgt, ir_graph *irg)
134 const char *msg = "";
136 if(!edges_activated(irg))
140 assert(node_is_in_irgs_storage(irg, src) && "source not in irg");
144 * Only do something, if the old and new target differ.
147 int is_block_edge = is_Block(src);
148 set *edges = _get_irg_edge_info(irg)->edges;
152 * This is scary, but:
153 * If two entries in a set do not have the same size, they are
154 * treated as unequal, ignoring the comparison function.
155 * So, edges from blocks have extra storage (they are
156 * ir_block_edge_t's).
158 * Also add the amount of registered private data to the
161 size_t size = EDGE_SIZE(src);
162 ir_edge_t *templ = alloca(size);
164 /* Initialize the edge template to search in the set. */
165 memset(templ, 0, size);
170 DEBUG_ONLY(templ->src_nr = get_irn_node_nr(src));
173 * If the target is NULL, the edge shall be deleted.
176 /* search the edge in the set. */
177 edge = set_find(edges, templ, size, edge_hash(templ));
179 /* mark the edge invalid if it was found */
181 ir_block_edge_t *block_edge = (ir_block_edge_t *) edge;
184 list_del(&edge->list);
190 * If the edge is a cf edge, we delete it also
191 * from the list of all block successor edges.
194 list_del(&block_edge->succ_list);
195 edge_change_cnt(old_tgt, -1);
199 /* If the edge was not found issue a warning on the debug stream */
201 msg = "edge to delete not found!\n";
206 * The target is not NULL and the old target differs
207 * from the new target, the edge shall be moved (if the
208 * old target was != NULL) or added (if the old target was
212 struct list_head *head = _get_irn_outs_head(tgt);
215 * The list head in the block of the edges target.
216 * Therein all control flow edges directed at that block
219 struct list_head *succ_head =
220 is_block_edge ? _get_block_succ_head(get_nodes_block(tgt)) : NULL;
222 ir_block_edge_t *block_edge;
225 if(!node_is_in_irgs_storage(irg, tgt))
228 assert(head->next && head->prev &&
229 "target list head must have been initialized");
232 * insert the edge, if it is not yet in the set or return
233 * the instance in the set.
235 edge = set_insert(edges, templ, size, edge_hash(templ));
236 block_edge = (ir_block_edge_t *) edge;
239 assert(!edge->invalid && "Invalid edge encountered");
242 /* If the old target is not null, the edge is moved. */
246 list_move(&edge->list, head);
248 /* If the edge is a cf edge, move it from the successor list. */
250 list_move(&block_edge->succ_list, succ_head);
252 edge_change_cnt(old_tgt, -1);
255 /* The old target was null, thus, the edge is newly created. */
258 list_add(&edge->list, head);
261 * If the edge is cf edge, enter it into the successor list
262 * of the target node's block.
265 list_add(&block_edge->succ_list, succ_head);
268 edge_change_cnt(tgt, +1);
272 /* If the target and the old target are equal, nothing is done. */
273 DBG((dbg, LEVEL_5, "announce out edge: %+F %d-> %+F(%+F): %s\n",
274 src, pos, tgt, old_tgt, msg));
277 void edges_node_deleted(ir_node *old, ir_graph *irg)
279 if(edges_activated(irg)) {
280 int not_a_block = !is_Block(old);
283 DBG((dbg, LEVEL_5, "node deleted: %+F\n", old));
285 /* Change to get_irn_n */
286 for(i = -not_a_block, n = get_irn_arity(old); i < n; ++i) {
287 ir_node *old_tgt = get_irn_n(old, i);
288 DBG((dbg, LEVEL_5, "\tdelete to old target %+F\n", old_tgt));
289 edges_notify_edge(old, i, NULL, old_tgt, irg);
295 void edges_invalidate(ir_node *irn, ir_graph *irg) {
296 edges_node_deleted(irn, irg);
300 * Post-Walker: notify all edges
302 static void build_edges_walker(ir_node *irn, void *data) {
303 ir_graph *irg = data;
304 int not_a_block = !is_Block(irn);
307 for (i = -not_a_block, n = get_irn_arity(irn); i < n; ++i)
308 edges_notify_edge(irn, i, get_irn_n(irn, i), NULL, irg);
312 * Pre-Walker: initializes the list-heads and set the out-count
315 static void init_lh_walker(ir_node *irn, void *data) {
316 INIT_LIST_HEAD(_get_irn_outs_head(irn));
318 INIT_LIST_HEAD(_get_block_succ_head(irn));
319 _get_irn_edge_info(irn)->out_count = 0;
323 * Visitor: initializes the list-heads and set the out-count
324 * of all nodes to 0 of nodes that are not seen so far.
326 static void visitor(ir_node *irn, void *data) {
327 if (irn_not_visited(irn)) {
328 mark_irn_visited(irn);
329 init_lh_walker(irn, data);
334 * Build the initial edge set.
335 * Beware, this is not a simple task because it suffers from two
337 * - the anchor set allows access to Nodes that may not be reachable from
339 * - the identities add nodes to the "root set" that are not yet reachable
340 * from End. However, after some transformations, the CSE may revival these
343 * These problems can be fixed using different strategies:
344 * - Add an age flag to every node. Whenever the edge of a node is older
345 * then the current edge, invalidate the edges of this node.
346 * While this would help for revivaled nodes, it increases memory and runtime.
347 * - Delete the identities set.
348 * Solves the revival problem, but may increase the memory consumption, as
349 * nodes cannot be revivaled at all.
350 * - Manually iterate over the identities root set. This did not consume more memory
351 * but increase the computation time because the |identies| >= |V|
353 * Currently, we use the last option.
355 void edges_activate(ir_graph *irg)
357 irg_edge_info_t *info = _get_irg_edge_info(irg);
360 edges_init_graph(irg);
361 irg_walk_graph(irg, init_lh_walker, build_edges_walker, irg);
362 irg_walk_anchors(irg, init_lh_walker, NULL, irg);
363 visit_all_identities(irg, visitor, irg);
366 void edges_deactivate(ir_graph *irg)
368 irg_edge_info_t *info = _get_irg_edge_info(irg);
372 del_set(info->edges);
377 int (edges_activated)(const ir_graph *irg)
379 return _edges_activated(irg);
384 * Reroute all use-edges from a node to another.
385 * @param from The node whose use-edges shall be withdrawn.
386 * @param to The node to which all the use-edges of @p from shall be
389 void edges_reroute(ir_node *from, ir_node *to, ir_graph *irg)
391 if(edges_activated(irg)) {
392 struct list_head *head = _get_irn_outs_head(from);
395 "reroute from %+F to %+F\n", from, to));
397 while(head != head->next) {
398 ir_edge_t *edge = list_entry(head->next, ir_edge_t, list);
399 // DBG((dbg, LEVEL_5, "\t%n %d\n", edge->src, edge->pos));
400 assert(edge->pos >= -1);
401 set_irn_n(edge->src, edge->pos, to);
406 static void verify_set_presence(ir_node *irn, void *data)
408 ir_graph *irg = data;
409 set *edges = _get_irg_edge_info(irg)->edges;
410 int not_a_block = !is_Block(irn);
413 for(i = 0, n = get_irn_arity(irn) + not_a_block; i < n; ++i) {
414 ir_block_edge_t space;
415 ir_edge_t *templ = (ir_edge_t *) &space;
417 size_t size = not_a_block ? sizeof(ir_edge_t) : sizeof(ir_block_edge_t);
420 templ->pos = i - not_a_block;
422 e = set_find(edges, templ, size, edge_hash(templ));
426 DBG((dbg, LEVEL_DEFAULT, "edge %+F,%d is missing\n", irn, templ->pos));
430 static void verify_list_presence(ir_node *irn, void *data)
434 foreach_out_edge(irn, e) {
435 ir_node *tgt = get_irn_n(e->src, e->pos);
437 DBG((dbg, LEVEL_DEFAULT, "edge %+F,%d is no out edge of %+F but of %+F\n",
438 e->src, e->pos, irn, tgt));
443 void edges_verify(ir_graph *irg)
445 set *edges = _get_irg_edge_info(irg)->edges;
448 /* Clear the present bit in all edges available. */
449 for(e = set_first(edges); e; e = set_next(edges))
452 irg_walk_graph(irg, verify_set_presence, verify_list_presence, irg);
455 * Dump all edges which are not invalid and not present.
456 * These edges are superfluous and their presence in the
459 for(e = set_first(edges); e; e = set_next(edges)) {
460 if(!e->invalid && !e->present)
461 DBG((dbg, LEVEL_DEFAULT, "edge %+F,%d is superfluous\n", e->src, e->pos));
465 void init_edges(void)
467 FIRM_DBG_REGISTER(dbg, DBG_EDGES);
468 /* firm_dbg_set_mask(dbg, -1); */
472 const ir_edge_t *(get_irn_out_edge_first)(const ir_node *irn)
474 return _get_irn_out_edge_first(irn);
477 const ir_edge_t *(get_irn_out_edge_next)(const ir_node *irn, const ir_edge_t *last)
479 return _get_irn_out_edge_next(irn, last);
482 ir_node *(get_edge_src_irn)(const ir_edge_t *edge)
484 return _get_edge_src_irn(edge);
487 int (get_edge_src_pos)(const ir_edge_t *edge)
489 return _get_edge_src_pos(edge);
492 int (get_irn_n_edges)(const ir_node *irn)
494 return _get_irn_n_edges(irn);