2 * This file is part of libFirm.
3 * Copyright (C) 2012 University of Karlsruhe.
8 * @brief Interface for interference graphs.
9 * @author Sebastian Hack
17 #include "lc_opts_enum.h"
29 #include "becopystat.h"
30 #include "becopyopt.h"
33 #include "beintlive_t.h"
35 void be_ifg_free(be_ifg_t *self)
40 static void nodes_walker(ir_node *bl, void *data)
42 nodes_iter_t *it = (nodes_iter_t*)data;
43 struct list_head *head = get_block_border_head(it->env, bl);
45 foreach_border_head(head, b) {
46 if (b->is_def && b->is_real) {
47 obstack_ptr_grow(&it->obst, b->irn);
53 nodes_iter_t be_ifg_nodes_begin(be_ifg_t const *const ifg)
56 obstack_init(&iter.obst);
61 irg_block_walk_graph(ifg->env->irg, nodes_walker, NULL, &iter);
62 obstack_ptr_grow(&iter.obst, NULL);
63 iter.nodes = (ir_node**)obstack_finish(&iter.obst);
67 ir_node *be_ifg_nodes_next(nodes_iter_t *const it)
69 if (it->curr < it->n) {
70 return it->nodes[it->curr++];
72 obstack_free(&it->obst, NULL);
77 static void find_neighbour_walker(ir_node *block, void *data)
79 neighbours_iter_t *it = (neighbours_iter_t*)data;
80 struct list_head *head = get_block_border_head(it->env, block);
81 be_lv_t *lv = be_get_irg_liveness(it->env->irg);
85 if (!be_is_live_in(lv, block, it->irn) && block != get_nodes_block(it->irn))
88 foreach_border_head(head, b) {
89 ir_node *irn = b->irn;
95 break; /* if we reached the end of the node's lifetime we can safely break */
98 /* if any other node than the one in question starts living, add it to the set */
99 ir_nodeset_insert(&it->neighbours, irn);
101 else if (!has_started) {
102 /* we only delete, if the live range in question has not yet started */
103 ir_nodeset_remove(&it->neighbours, irn);
109 static void find_neighbours(const be_ifg_t *ifg, neighbours_iter_t *it, const ir_node *irn)
114 ir_nodeset_init(&it->neighbours);
116 dom_tree_walk(get_nodes_block(irn), find_neighbour_walker, NULL, it);
118 ir_nodeset_iterator_init(&it->iter, &it->neighbours);
121 static inline void neighbours_break(neighbours_iter_t *it, int force)
124 assert(it->valid == 1);
125 ir_nodeset_destroy(&it->neighbours);
129 static ir_node *get_next_neighbour(neighbours_iter_t *it)
131 ir_node *res = ir_nodeset_iterator_next(&it->iter);
134 ir_nodeset_destroy(&it->neighbours);
139 ir_node *be_ifg_neighbours_begin(const be_ifg_t *ifg, neighbours_iter_t *iter,
142 find_neighbours(ifg, iter, irn);
143 return get_next_neighbour(iter);
146 ir_node *be_ifg_neighbours_next(neighbours_iter_t *iter)
148 return get_next_neighbour(iter);
151 void be_ifg_neighbours_break(neighbours_iter_t *iter)
153 neighbours_break(iter, 1);
156 static inline void free_clique_iter(cliques_iter_t *it)
159 obstack_free(&it->ob, NULL);
160 del_pset(it->living);
163 static void get_blocks_dom_order(ir_node *blk, void *env)
165 cliques_iter_t *it = (cliques_iter_t*)env;
166 obstack_ptr_grow(&it->ob, blk);
170 * NOTE: Be careful when changing this function!
171 * First understand the control flow of consecutive calls.
173 static inline int get_next_clique(cliques_iter_t *it)
176 /* continue in the block we left the last time */
177 for (; it->blk < it->n_blocks; it->blk++) {
178 int output_on_shrink = 0;
179 struct list_head *head = get_block_border_head(it->cenv, it->blocks[it->blk]);
181 /* on entry to a new block set the first border ... */
183 it->bor = head->prev;
185 /* ... otherwise continue with the border we left the last time */
186 for (; it->bor != head; it->bor = it->bor->prev) {
187 border_t *b = list_entry(it->bor, border_t, list);
189 /* if its a definition irn starts living */
191 pset_insert_ptr(it->living, b->irn);
193 output_on_shrink = 1;
196 /* if its the last usage the irn dies */
198 /* before shrinking the set, return the current maximal clique */
199 if (output_on_shrink) {
202 /* fill the output buffer */
203 foreach_pset(it->living, ir_node, irn) {
204 it->buf[count++] = irn;
207 assert(count > 0 && "We have a 'last usage', so there must be sth. in it->living");
212 pset_remove_ptr(it->living, b->irn);
217 assert(0 == pset_count(it->living) && "Something has survived! (At the end of the block it->living must be empty)");
220 if (it->n_blocks != -1)
221 free_clique_iter(it);
226 int be_ifg_cliques_begin(const be_ifg_t *ifg, cliques_iter_t *it,
229 obstack_init(&it->ob);
230 dom_tree_walk_irg(ifg->env->irg, get_blocks_dom_order, NULL, it);
234 it->n_blocks = obstack_object_size(&it->ob) / sizeof(void *);
235 it->blocks = (ir_node**)obstack_finish(&it->ob);
238 it->living = pset_new_ptr(2 * arch_register_class_n_regs(it->cenv->cls));
240 return get_next_clique(it);
243 int be_ifg_cliques_next(cliques_iter_t *iter)
245 return get_next_clique(iter);
248 void be_ifg_cliques_break(cliques_iter_t *iter)
250 free_clique_iter(iter);
253 int be_ifg_degree(const be_ifg_t *ifg, const ir_node *irn)
255 neighbours_iter_t it;
257 find_neighbours(ifg, &it, irn);
258 degree = ir_nodeset_size(&it.neighbours);
259 neighbours_break(&it, 1);
263 be_ifg_t *be_create_ifg(const be_chordal_env_t *env)
265 be_ifg_t *ifg = XMALLOC(be_ifg_t);
271 static bool consider_component_node(bitset_t *const seen, ir_node *const irn)
273 if (bitset_is_set(seen, get_irn_idx(irn)))
275 bitset_set(seen, get_irn_idx(irn));
277 arch_register_req_t const *const req = arch_get_irn_register_req(irn);
278 if (arch_register_req_is(req, ignore))
284 static void int_comp_rec(be_ifg_t *ifg, ir_node *n, bitset_t *seen)
286 neighbours_iter_t neigh_it;
288 be_ifg_foreach_neighbour(ifg, &neigh_it, n, m) {
289 if (consider_component_node(seen, m))
290 int_comp_rec(ifg, m, seen);
294 void be_ifg_stat(ir_graph *irg, be_ifg_t *ifg, be_ifg_stat_t *stat)
299 bitset_t *const seen = bitset_malloc(get_irg_last_idx(irg));
300 be_ifg_foreach_node(ifg, n) {
303 neighbours_iter_t neigh_it;
304 be_ifg_foreach_neighbour(ifg, &neigh_it, n, m) {
308 if (consider_component_node(seen, n)) {
310 int_comp_rec(ifg, n, seen);
315 stat->n_nodes = n_nodes;
316 /* Every interference edge was counted twice, once for each end. */
317 stat->n_edges = n_edges / 2;
318 stat->n_comps = n_comps;