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 int be_ifg_connected(const be_ifg_t *ifg, const ir_node *a, const ir_node *b)
42 be_lv_t *lv = be_get_irg_liveness(ifg->env->irg);
43 return be_values_interfere(lv, a, b);
46 static void nodes_walker(ir_node *bl, void *data)
48 nodes_iter_t *it = (nodes_iter_t*)data;
49 struct list_head *head = get_block_border_head(it->env, bl);
51 foreach_border_head(head, b) {
52 if (b->is_def && b->is_real) {
53 obstack_ptr_grow(&it->obst, b->irn);
59 static void find_nodes(const be_ifg_t *ifg, nodes_iter_t *iter)
61 obstack_init(&iter->obst);
66 irg_block_walk_graph(ifg->env->irg, nodes_walker, NULL, iter);
67 obstack_ptr_grow(&iter->obst, NULL);
68 iter->nodes = (ir_node**)obstack_finish(&iter->obst);
71 static inline void node_break(nodes_iter_t *it, int force)
73 if ((it->curr >= it->n || force) && it->nodes) {
74 obstack_free(&it->obst, NULL);
79 static ir_node *get_next_node(nodes_iter_t *it)
84 res = it->nodes[it->curr++];
91 ir_node *be_ifg_nodes_begin(const be_ifg_t *ifg, nodes_iter_t *iter)
93 find_nodes(ifg, iter);
94 return get_next_node(iter);
97 ir_node *be_ifg_nodes_next(nodes_iter_t *iter)
99 return get_next_node(iter);
102 void be_ifg_nodes_break(nodes_iter_t *iter)
107 static void find_neighbour_walker(ir_node *block, void *data)
109 neighbours_iter_t *it = (neighbours_iter_t*)data;
110 struct list_head *head = get_block_border_head(it->env, block);
111 be_lv_t *lv = be_get_irg_liveness(it->env->irg);
115 if (!be_is_live_in(lv, block, it->irn) && block != get_nodes_block(it->irn))
118 foreach_border_head(head, b) {
119 ir_node *irn = b->irn;
121 if (irn == it->irn) {
125 break; /* if we reached the end of the node's lifetime we can safely break */
127 else if (b->is_def) {
128 /* if any other node than the one in question starts living, add it to the set */
129 ir_nodeset_insert(&it->neighbours, irn);
131 else if (!has_started) {
132 /* we only delete, if the live range in question has not yet started */
133 ir_nodeset_remove(&it->neighbours, irn);
139 static void find_neighbours(const be_ifg_t *ifg, neighbours_iter_t *it, const ir_node *irn)
144 ir_nodeset_init(&it->neighbours);
146 dom_tree_walk(get_nodes_block(irn), find_neighbour_walker, NULL, it);
148 ir_nodeset_iterator_init(&it->iter, &it->neighbours);
151 static inline void neighbours_break(neighbours_iter_t *it, int force)
154 assert(it->valid == 1);
155 ir_nodeset_destroy(&it->neighbours);
159 static ir_node *get_next_neighbour(neighbours_iter_t *it)
161 ir_node *res = ir_nodeset_iterator_next(&it->iter);
164 ir_nodeset_destroy(&it->neighbours);
169 ir_node *be_ifg_neighbours_begin(const be_ifg_t *ifg, neighbours_iter_t *iter,
172 find_neighbours(ifg, iter, irn);
173 return get_next_neighbour(iter);
176 ir_node *be_ifg_neighbours_next(neighbours_iter_t *iter)
178 return get_next_neighbour(iter);
181 void be_ifg_neighbours_break(neighbours_iter_t *iter)
183 neighbours_break(iter, 1);
186 static inline void free_clique_iter(cliques_iter_t *it)
189 obstack_free(&it->ob, NULL);
190 del_pset(it->living);
193 static void get_blocks_dom_order(ir_node *blk, void *env)
195 cliques_iter_t *it = (cliques_iter_t*)env;
196 obstack_ptr_grow(&it->ob, blk);
200 * NOTE: Be careful when changing this function!
201 * First understand the control flow of consecutive calls.
203 static inline int get_next_clique(cliques_iter_t *it)
206 /* continue in the block we left the last time */
207 for (; it->blk < it->n_blocks; it->blk++) {
208 int output_on_shrink = 0;
209 struct list_head *head = get_block_border_head(it->cenv, it->blocks[it->blk]);
211 /* on entry to a new block set the first border ... */
213 it->bor = head->prev;
215 /* ... otherwise continue with the border we left the last time */
216 for (; it->bor != head; it->bor = it->bor->prev) {
217 border_t *b = list_entry(it->bor, border_t, list);
219 /* if its a definition irn starts living */
221 pset_insert_ptr(it->living, b->irn);
223 output_on_shrink = 1;
226 /* if its the last usage the irn dies */
228 /* before shrinking the set, return the current maximal clique */
229 if (output_on_shrink) {
232 /* fill the output buffer */
233 foreach_pset(it->living, ir_node, irn) {
234 it->buf[count++] = irn;
237 assert(count > 0 && "We have a 'last usage', so there must be sth. in it->living");
242 pset_remove_ptr(it->living, b->irn);
247 assert(0 == pset_count(it->living) && "Something has survived! (At the end of the block it->living must be empty)");
250 if (it->n_blocks != -1)
251 free_clique_iter(it);
256 int be_ifg_cliques_begin(const be_ifg_t *ifg, cliques_iter_t *it,
259 obstack_init(&it->ob);
260 dom_tree_walk_irg(ifg->env->irg, get_blocks_dom_order, NULL, it);
264 it->n_blocks = obstack_object_size(&it->ob) / sizeof(void *);
265 it->blocks = (ir_node**)obstack_finish(&it->ob);
268 it->living = pset_new_ptr(2 * arch_register_class_n_regs(it->cenv->cls));
270 return get_next_clique(it);
273 int be_ifg_cliques_next(cliques_iter_t *iter)
275 return get_next_clique(iter);
278 void be_ifg_cliques_break(cliques_iter_t *iter)
280 free_clique_iter(iter);
283 int be_ifg_degree(const be_ifg_t *ifg, const ir_node *irn)
285 neighbours_iter_t it;
287 find_neighbours(ifg, &it, irn);
288 degree = ir_nodeset_size(&it.neighbours);
289 neighbours_break(&it, 1);
293 be_ifg_t *be_create_ifg(const be_chordal_env_t *env)
295 be_ifg_t *ifg = XMALLOC(be_ifg_t);
301 static void int_comp_rec(be_ifg_t *ifg, ir_node *n, bitset_t *seen)
303 neighbours_iter_t neigh_it;
305 be_ifg_foreach_neighbour(ifg, &neigh_it, n, m) {
306 if (bitset_is_set(seen, get_irn_idx(m)))
309 arch_register_req_t const *const req = arch_get_irn_register_req(m);
310 if (arch_register_req_is(req, ignore))
313 bitset_set(seen, get_irn_idx(m));
314 int_comp_rec(ifg, m, seen);
319 static int int_component_stat(ir_graph *irg, be_ifg_t *ifg)
322 nodes_iter_t nodes_it;
323 bitset_t *seen = bitset_malloc(get_irg_last_idx(irg));
325 be_ifg_foreach_node(ifg, &nodes_it, n) {
326 if (bitset_is_set(seen, get_irn_idx(n)))
329 arch_register_req_t const *const req = arch_get_irn_register_req(n);
330 if (arch_register_req_is(req, ignore))
334 bitset_set(seen, get_irn_idx(n));
335 int_comp_rec(ifg, n, seen);
342 void be_ifg_stat(ir_graph *irg, be_ifg_t *ifg, be_ifg_stat_t *stat)
344 nodes_iter_t nodes_it;
345 neighbours_iter_t neigh_it;
347 memset(stat, 0, sizeof(stat[0]));
350 be_ifg_foreach_node(ifg, &nodes_it, n) {
352 be_ifg_foreach_neighbour(ifg, &neigh_it, n, m) {
357 /* Every interference edge was counted twice, once for each end. */
358 stat->n_edges = n_edges / 2;
359 stat->n_comps = int_component_stat(irg, ifg);