2 * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
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.
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.
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
22 * @brief Simple copy minimization heuristics.
23 * @author Christian Wuerdig
27 * This is the C implementation of the mst algorithm
28 * originally written in Java by Sebastian Hack.
29 * (also known as "heur3" :)
30 * Performs simple copy minimization.
34 #define DISABLE_STATEV
41 #include "raw_bitset.h"
42 #include "irphase_t.h"
58 #include "becopyopt_t.h"
62 #define COL_COST_INFEASIBLE DBL_MAX
63 #define AFF_NEIGHBOUR_FIX_BENEFIT 128.0
64 #define NEIGHBOUR_CONSTR_COSTS 64.0
69 #define DBG_AFF_CHUNK(env, level, chunk) do { if (firm_dbg_get_mask(dbg) & (level)) dbg_aff_chunk((env), (chunk)); } while(0)
70 #define DBG_COL_COST(env, level, cost) do { if (firm_dbg_get_mask(dbg) & (level)) dbg_col_cost((env), (cost)); } while(0)
72 static firm_dbg_module_t *dbg = NULL;
76 #define DBG_AFF_CHUNK(env, level, chunk)
77 #define DBG_COL_COST(env, level, cost)
82 #define REAL(C) (C ## f)
84 static unsigned last_chunk_id = 0;
85 static int recolor_limit = 7;
86 static real_t dislike_influence = REAL(0.1);
88 typedef struct _col_cost_t {
96 typedef struct _aff_chunk_t {
97 const ir_node **n; /**< An ARR_F containing all nodes of the chunk. */
98 const ir_node **interfere; /**< An ARR_F containing all inference. */
99 int weight; /**< Weight of this chunk */
100 unsigned weight_consistent : 1; /**< Set if the weight is consistent. */
101 unsigned deleted : 1; /**< For debugging: Set if the was deleted. */
102 unsigned id; /**< An id of this chunk. */
104 col_cost_t color_affinity[1];
110 typedef struct _aff_edge_t {
111 const ir_node *src; /**< Source node. */
112 const ir_node *tgt; /**< Target node. */
113 int weight; /**< The weight of this edge. */
116 /* main coalescing environment */
117 typedef struct _co_mst_env_t {
118 int n_regs; /**< number of regs in class */
119 int k; /**< number of non-ignore registers in class */
120 bitset_t *ignore_regs; /**< set containing all global ignore registers */
121 ir_phase ph; /**< phase object holding data for nodes */
122 pqueue_t *chunks; /**< priority queue for chunks */
123 pset *chunkset; /**< set holding all chunks */
124 be_ifg_t *ifg; /**< the interference graph */
125 copy_opt_t *co; /**< the copy opt object */
126 unsigned chunk_visited;
127 col_cost_t **single_cols;
130 /* stores coalescing related information for a node */
131 typedef struct _co_mst_irn_t {
132 const ir_node *irn; /**< the irn this information belongs to */
133 aff_chunk_t *chunk; /**< the chunk this irn belongs to */
134 bitset_t *adm_colors; /**< set of admissible colors for this irn */
135 ir_node **int_neighs; /**< array of all interfering neighbours (cached for speed reasons) */
136 int n_neighs; /**< length of the interfering neighbours array. */
137 int int_aff_neigh; /**< number of interfering affinity neighbours */
138 int col; /**< color currently assigned */
139 int init_col; /**< the initial color */
140 int tmp_col; /**< a temporary assigned color */
141 unsigned fixed : 1; /**< the color is fixed */
142 struct list_head list; /**< Queue for coloring undo. */
143 real_t constr_factor;
146 #define get_co_mst_irn(mst_env, irn) (phase_get_or_set_irn_data(&(mst_env)->ph, (irn)))
148 typedef int decide_func_t(const co_mst_irn_t *node, int col);
153 * Write a chunk to stderr for debugging.
155 static void dbg_aff_chunk(const co_mst_env_t *env, const aff_chunk_t *c) {
158 if (c->weight_consistent)
159 ir_fprintf(stderr, " $%d ", c->weight);
160 ir_fprintf(stderr, "{");
161 for (i = 0, l = ARR_LEN(c->n); i < l; ++i) {
162 const ir_node *n = c->n[i];
163 ir_fprintf(stderr, " %+F,", n);
165 ir_fprintf(stderr, "}");
169 * Dump all admissible colors to stderr.
171 static void dbg_admissible_colors(const co_mst_env_t *env, const co_mst_irn_t *node) {
175 if (bitset_popcnt(node->adm_colors) < 1)
176 fprintf(stderr, "no admissible colors?!?");
178 bitset_foreach(node->adm_colors, idx) {
179 fprintf(stderr, " %d", idx);
185 * Dump color-cost pairs to stderr.
187 static void dbg_col_cost(const co_mst_env_t *env, const col_cost_t *cost) {
189 for (i = 0; i < env->n_regs; ++i)
190 fprintf(stderr, " (%d, %.4f)", cost[i].col, cost[i].cost);
193 #endif /* DEBUG_libfirm */
195 static inline int get_mst_irn_col(const co_mst_irn_t *node) {
196 return node->tmp_col >= 0 ? node->tmp_col : node->col;
200 * @return 1 if node @p node has color @p col, 0 otherwise.
202 static int decider_has_color(const co_mst_irn_t *node, int col) {
203 return get_mst_irn_col(node) == col;
207 * @return 1 if node @p node has not color @p col, 0 otherwise.
209 static int decider_hasnot_color(const co_mst_irn_t *node, int col) {
210 return get_mst_irn_col(node) != col;
214 * Always returns true.
216 static int decider_always_yes(const co_mst_irn_t *node, int col) {
222 /** compares two affinity edges by its weight */
223 static int cmp_aff_edge(const void *a, const void *b) {
224 const aff_edge_t *e1 = a;
225 const aff_edge_t *e2 = b;
227 if (e2->weight == e1->weight) {
228 if (e2->src->node_idx == e1->src->node_idx)
229 return QSORT_CMP(e2->tgt->node_idx, e1->tgt->node_idx);
231 return QSORT_CMP(e2->src->node_idx, e1->src->node_idx);
233 /* sort in descending order */
234 return QSORT_CMP(e2->weight, e1->weight);
237 /** compares to color-cost pairs */
238 static __attribute__((unused)) int cmp_col_cost_lt(const void *a, const void *b) {
239 const col_cost_t *c1 = a;
240 const col_cost_t *c2 = b;
241 real_t diff = c1->cost - c2->cost;
242 return (diff > 0) - (diff < 0);
245 static int cmp_col_cost_gt(const void *a, const void *b) {
246 const col_cost_t *c1 = a;
247 const col_cost_t *c2 = b;
248 real_t diff = c2->cost - c1->cost;
249 return (diff > 0) - (diff < 0);
253 * Creates a new affinity chunk
255 static inline aff_chunk_t *new_aff_chunk(co_mst_env_t *env) {
256 aff_chunk_t *c = XMALLOCF(aff_chunk_t, color_affinity, env->n_regs);
257 c->n = NEW_ARR_F(const ir_node *, 0);
258 c->interfere = NEW_ARR_F(const ir_node *, 0);
260 c->weight_consistent = 0;
262 c->id = ++last_chunk_id;
264 pset_insert(env->chunkset, c, c->id);
269 * Frees all memory allocated by an affinity chunk.
271 static inline void delete_aff_chunk(co_mst_env_t *env, aff_chunk_t *c) {
272 pset_remove(env->chunkset, c, c->id);
273 DEL_ARR_F(c->interfere);
280 * binary search of sorted nodes.
282 * @return the position where n is found in the array arr or ~pos
283 * if the nodes is not here.
285 static inline int nodes_bsearch(const ir_node **arr, const ir_node *n) {
286 int hi = ARR_LEN(arr);
290 int md = lo + ((hi - lo) >> 1);
303 /** Check if a node n can be found inside arr. */
304 static int node_contains(const ir_node **arr, const ir_node *n) {
305 int i = nodes_bsearch(arr, n);
310 * Insert a node into the sorted nodes list.
312 * @return 1 if the node was inserted, 0 else
314 static int nodes_insert(const ir_node ***arr, const ir_node *irn) {
315 int idx = nodes_bsearch(*arr, irn);
318 int i, n = ARR_LEN(*arr);
321 ARR_APP1(const ir_node *, *arr, irn);
326 for (i = n - 1; i >= idx; --i)
335 * Adds a node to an affinity chunk
337 static inline void aff_chunk_add_node(aff_chunk_t *c, co_mst_irn_t *node) {
340 if (! nodes_insert(&c->n, node->irn))
343 c->weight_consistent = 0;
346 for (i = node->n_neighs - 1; i >= 0; --i) {
347 ir_node *neigh = node->int_neighs[i];
348 nodes_insert(&c->interfere, neigh);
353 * In case there is no phase information for irn, initialize it.
355 static void *co_mst_irn_init(ir_phase *ph, const ir_node *irn, void *old) {
356 co_mst_irn_t *res = old ? old : phase_alloc(ph, sizeof(res[0]));
357 co_mst_env_t *env = ph->priv;
360 const arch_register_req_t *req;
361 void *nodes_it = be_ifg_nodes_iter_alloca(env->ifg);
369 res->int_neighs = NULL;
370 res->int_aff_neigh = 0;
371 res->col = arch_register_get_index(arch_get_irn_register(irn));
372 res->init_col = res->col;
373 INIT_LIST_HEAD(&res->list);
375 DB((dbg, LEVEL_4, "Creating phase info for %+F\n", irn));
377 /* set admissible registers */
378 res->adm_colors = bitset_obstack_alloc(phase_obst(ph), env->n_regs);
380 /* Exclude colors not assignable to the irn */
381 req = arch_get_register_req_out(irn);
382 if (arch_register_req_is(req, limited))
383 rbitset_copy_to_bitset(req->limited, res->adm_colors);
385 bitset_set_all(res->adm_colors);
387 /* exclude global ignore registers as well */
388 bitset_andnot(res->adm_colors, env->ignore_regs);
390 /* compute the constraint factor */
391 res->constr_factor = (real_t) (1 + env->n_regs - bitset_popcnt(res->adm_colors)) / env->n_regs;
393 /* set the number of interfering affinity neighbours to -1, they are calculated later */
394 res->int_aff_neigh = -1;
396 /* build list of interfering neighbours */
398 be_ifg_foreach_neighbour(env->ifg, nodes_it, irn, neigh) {
399 if (!arch_irn_is(neigh, ignore)) {
400 obstack_ptr_grow(phase_obst(ph), neigh);
404 res->int_neighs = obstack_finish(phase_obst(ph));
411 * Check if affinity chunk @p chunk interferes with node @p irn.
413 static inline int aff_chunk_interferes(const aff_chunk_t *chunk, const ir_node *irn) {
414 return node_contains(chunk->interfere, irn);
418 * Check if there are interference edges from c1 to c2.
420 * @param c2 Another chunk
421 * @return 1 if there are interferences between nodes of c1 and c2, 0 otherwise.
423 static inline int aff_chunks_interfere(const aff_chunk_t *c1, const aff_chunk_t *c2) {
429 /* check if there is a node in c2 having an interfering neighbor in c1 */
430 for (i = ARR_LEN(c2->n) - 1; i >= 0; --i) {
431 const ir_node *irn = c2->n[i];
433 if (node_contains(c1->interfere, irn))
440 * Returns the affinity chunk of @p irn or creates a new
441 * one with @p irn as element if there is none assigned.
443 static inline aff_chunk_t *get_aff_chunk(co_mst_env_t *env, const ir_node *irn) {
444 co_mst_irn_t *node = get_co_mst_irn(env, irn);
449 * Let chunk(src) absorb the nodes of chunk(tgt) (only possible when there
450 * are no interference edges from chunk(src) to chunk(tgt)).
451 * @return 1 if successful, 0 if not possible
453 static int aff_chunk_absorb(co_mst_env_t *env, const ir_node *src, const ir_node *tgt) {
454 aff_chunk_t *c1 = get_aff_chunk(env, src);
455 aff_chunk_t *c2 = get_aff_chunk(env, tgt);
458 DB((dbg, LEVEL_4, "Attempt to let c1 (id %u): ", c1 ? c1->id : 0));
460 DBG_AFF_CHUNK(env, LEVEL_4, c1);
462 DB((dbg, LEVEL_4, "{%+F}", src));
464 DB((dbg, LEVEL_4, "\n\tabsorb c2 (id %u): ", c2 ? c2->id : 0));
466 DBG_AFF_CHUNK(env, LEVEL_4, c2);
468 DB((dbg, LEVEL_4, "{%+F}", tgt));
470 DB((dbg, LEVEL_4, "\n"));
475 /* no chunk exists */
476 co_mst_irn_t *mirn = get_co_mst_irn(env, src);
479 for (i = mirn->n_neighs - 1; i >= 0; --i) {
480 if (mirn->int_neighs[i] == tgt)
484 /* create one containing both nodes */
485 c1 = new_aff_chunk(env);
486 aff_chunk_add_node(c1, get_co_mst_irn(env, src));
487 aff_chunk_add_node(c1, get_co_mst_irn(env, tgt));
491 /* c2 already exists */
492 if (! aff_chunk_interferes(c2, src)) {
493 aff_chunk_add_node(c2, get_co_mst_irn(env, src));
497 } else if (c2 == NULL) {
498 /* c1 already exists */
499 if (! aff_chunk_interferes(c1, tgt)) {
500 aff_chunk_add_node(c1, get_co_mst_irn(env, tgt));
503 } else if (c1 != c2 && ! aff_chunks_interfere(c1, c2)) {
506 for (idx = 0, len = ARR_LEN(c2->n); idx < len; ++idx)
507 aff_chunk_add_node(c1, get_co_mst_irn(env, c2->n[idx]));
509 for (idx = 0, len = ARR_LEN(c2->interfere); idx < len; ++idx) {
510 const ir_node *irn = c2->interfere[idx];
511 nodes_insert(&c1->interfere, irn);
514 c1->weight_consistent = 0;
516 delete_aff_chunk(env, c2);
519 DB((dbg, LEVEL_4, " ... c1 interferes with c2, skipped\n"));
523 DB((dbg, LEVEL_4, " ... absorbed\n"));
528 * Assures that the weight of the given chunk is consistent.
530 static void aff_chunk_assure_weight(co_mst_env_t *env, aff_chunk_t *c) {
531 if (! c->weight_consistent) {
535 for (i = 0; i < env->n_regs; ++i) {
536 c->color_affinity[i].col = i;
537 c->color_affinity[i].cost = REAL(0.0);
540 for (idx = 0, len = ARR_LEN(c->n); idx < len; ++idx) {
541 const ir_node *n = c->n[idx];
542 const affinity_node_t *an = get_affinity_info(env->co, n);
543 co_mst_irn_t *node = get_co_mst_irn(env, n);
546 if (node->constr_factor > REAL(0.0)) {
548 bitset_foreach (node->adm_colors, col)
549 c->color_affinity[col].cost += node->constr_factor;
554 co_gs_foreach_neighb(an, neigh) {
555 const ir_node *m = neigh->irn;
557 /* skip ignore nodes */
558 if (arch_irn_is(m, ignore))
561 w += node_contains(c->n, m) ? neigh->costs : 0;
566 for (i = 0; i < env->n_regs; ++i)
567 c->color_affinity[i].cost *= (REAL(1.0) / ARR_LEN(c->n));
570 // c->weight = bitset_popcnt(c->nodes);
571 c->weight_consistent = 1;
576 * Count the number of interfering affinity neighbours
578 static int count_interfering_aff_neighs(co_mst_env_t *env, const affinity_node_t *an) {
579 const neighb_t *neigh;
580 const ir_node *irn = an->irn;
581 const co_mst_irn_t *node = get_co_mst_irn(env, irn);
584 co_gs_foreach_neighb(an, neigh) {
585 const ir_node *n = neigh->irn;
588 /* skip ignore nodes */
589 if (arch_irn_is(n, ignore))
592 /* check if the affinity neighbour interfere */
593 for (i = 0; i < node->n_neighs; ++i) {
594 if (node->int_neighs[i] == n) {
605 * Build chunks of nodes connected by affinity edges.
606 * We start at the heaviest affinity edge.
607 * The chunks of the two edge-defining nodes will be
608 * merged if there are no interference edges from one
609 * chunk to the other.
611 static void build_affinity_chunks(co_mst_env_t *env) {
612 void *nodes_it = be_ifg_nodes_iter_alloca(env->ifg);
613 aff_edge_t *edges = NEW_ARR_F(aff_edge_t, 0);
616 aff_chunk_t *curr_chunk;
618 /* at first we create the affinity edge objects */
619 be_ifg_foreach_node(env->ifg, nodes_it, n) {
620 int n_idx = get_irn_idx(n);
624 /* skip ignore nodes */
625 if (arch_irn_is(n, ignore))
628 n1 = get_co_mst_irn(env, n);
629 an = get_affinity_info(env->co, n);
634 if (n1->int_aff_neigh < 0)
635 n1->int_aff_neigh = count_interfering_aff_neighs(env, an);
637 /* build the affinity edges */
638 co_gs_foreach_neighb(an, neigh) {
639 const ir_node *m = neigh->irn;
640 int m_idx = get_irn_idx(m);
642 /* record the edge in only one direction */
647 /* skip ignore nodes */
648 if (arch_irn_is(m, ignore))
654 n2 = get_co_mst_irn(env, m);
655 if (n2->int_aff_neigh < 0) {
656 affinity_node_t *am = get_affinity_info(env->co, m);
657 n2->int_aff_neigh = count_interfering_aff_neighs(env, am);
660 * these weights are pure hackery ;-).
661 * It's not chriswue's fault but mine.
663 edge.weight = neigh->costs;
664 ARR_APP1(aff_edge_t, edges, edge);
670 /* now: sort edges and build the affinity chunks */
671 len = ARR_LEN(edges);
672 qsort(edges, len, sizeof(edges[0]), cmp_aff_edge);
673 for (i = 0; i < len; ++i) {
674 DBG((dbg, LEVEL_1, "edge (%u,%u) %f\n", edges[i].src->node_idx, edges[i].tgt->node_idx, edges[i].weight));
676 (void)aff_chunk_absorb(env, edges[i].src, edges[i].tgt);
679 /* now insert all chunks into a priority queue */
680 foreach_pset(env->chunkset, curr_chunk) {
681 aff_chunk_assure_weight(env, curr_chunk);
683 DBG((dbg, LEVEL_1, "entry #%u", curr_chunk->id));
684 DBG_AFF_CHUNK(env, LEVEL_1, curr_chunk);
685 DBG((dbg, LEVEL_1, "\n"));
687 pqueue_put(env->chunks, curr_chunk, curr_chunk->weight);
690 foreach_phase_irn(&env->ph, n) {
691 co_mst_irn_t *mirn = get_co_mst_irn(env, n);
693 if (mirn->chunk == NULL) {
694 /* no chunk is allocated so far, do it now */
695 aff_chunk_t *curr_chunk = new_aff_chunk(env);
696 aff_chunk_add_node(curr_chunk, mirn);
698 aff_chunk_assure_weight(env, curr_chunk);
700 DBG((dbg, LEVEL_1, "entry #%u", curr_chunk->id));
701 DBG_AFF_CHUNK(env, LEVEL_1, curr_chunk);
702 DBG((dbg, LEVEL_1, "\n"));
704 pqueue_put(env->chunks, curr_chunk, curr_chunk->weight);
711 static __attribute__((unused)) void chunk_order_nodes(co_mst_env_t *env, aff_chunk_t *chunk)
713 pqueue_t *grow = new_pqueue();
714 const ir_node *max_node = NULL;
718 for (i = ARR_LEN(chunk->n) - 1; i >= 0; i--) {
719 const ir_node *irn = chunk->n[i];
720 affinity_node_t *an = get_affinity_info(env->co, irn);
724 if (arch_irn_is(irn, ignore))
728 co_gs_foreach_neighb(an, neigh)
731 if (w > max_weight) {
739 bitset_t *visited = bitset_irg_malloc(env->co->irg);
741 for (i = ARR_LEN(chunk->n) - 1; i >= 0; --i)
742 bitset_add_irn(visited, chunk->n[i]);
744 pqueue_put(grow, (void *) max_node, max_weight);
745 bitset_remv_irn(visited, max_node);
747 while (!pqueue_empty(grow)) {
748 ir_node *irn = pqueue_pop_front(grow);
749 affinity_node_t *an = get_affinity_info(env->co, irn);
752 if (arch_irn_is(irn, ignore))
755 assert(i <= ARR_LEN(chunk->n));
760 /* build the affinity edges */
761 co_gs_foreach_neighb(an, neigh) {
762 co_mst_irn_t *node = get_co_mst_irn(env, neigh->irn);
764 if (bitset_contains_irn(visited, node->irn)) {
765 pqueue_put(grow, (void *) neigh->irn, neigh->costs);
766 bitset_remv_irn(visited, node->irn);
772 bitset_free(visited);
777 * Greedy collect affinity neighbours into thew new chunk @p chunk starting at node @p node.
779 static void expand_chunk_from(co_mst_env_t *env, co_mst_irn_t *node, bitset_t *visited,
780 aff_chunk_t *chunk, aff_chunk_t *orig_chunk, decide_func_t *decider, int col)
782 waitq *nodes = new_waitq();
784 DBG((dbg, LEVEL_1, "\n\tExpanding new chunk (#%u) from %+F, color %d:", chunk->id, node->irn, col));
786 /* init queue and chunk */
787 waitq_put(nodes, node);
788 bitset_set(visited, get_irn_idx(node->irn));
789 aff_chunk_add_node(chunk, node);
790 DB((dbg, LEVEL_1, " %+F", node->irn));
792 /* as long as there are nodes in the queue */
793 while (! waitq_empty(nodes)) {
794 co_mst_irn_t *n = waitq_get(nodes);
795 affinity_node_t *an = get_affinity_info(env->co, n->irn);
797 /* check all affinity neighbors */
800 co_gs_foreach_neighb(an, neigh) {
801 const ir_node *m = neigh->irn;
802 int m_idx = get_irn_idx(m);
805 /* skip ignore nodes */
806 if (arch_irn_is(m, ignore))
809 n2 = get_co_mst_irn(env, m);
811 if (! bitset_is_set(visited, m_idx) &&
814 ! aff_chunk_interferes(chunk, m) &&
815 node_contains(orig_chunk->n, m))
818 following conditions are met:
819 - neighbour is not visited
820 - neighbour likes the color
821 - neighbour has not yet a fixed color
822 - the new chunk doesn't interfere with the neighbour
823 - neighbour belongs or belonged once to the original chunk
825 bitset_set(visited, m_idx);
826 aff_chunk_add_node(chunk, n2);
827 DB((dbg, LEVEL_1, " %+F", n2->irn));
828 /* enqueue for further search */
829 waitq_put(nodes, n2);
835 DB((dbg, LEVEL_1, "\n"));
841 * Fragment the given chunk into chunks having given color and not having given color.
843 static aff_chunk_t *fragment_chunk(co_mst_env_t *env, int col, aff_chunk_t *c, waitq *tmp) {
844 bitset_t *visited = bitset_irg_malloc(env->co->irg);
846 aff_chunk_t *best = NULL;
848 for (idx = 0, len = ARR_LEN(c->n); idx < len; ++idx) {
851 aff_chunk_t *tmp_chunk;
852 decide_func_t *decider;
856 if (bitset_is_set(visited, get_irn_idx(irn)))
859 node = get_co_mst_irn(env, irn);
861 if (get_mst_irn_col(node) == col) {
862 decider = decider_has_color;
864 DBG((dbg, LEVEL_4, "\tcolor %d wanted\n", col));
867 decider = decider_hasnot_color;
869 DBG((dbg, LEVEL_4, "\tcolor %d forbidden\n", col));
872 /* create a new chunk starting at current node */
873 tmp_chunk = new_aff_chunk(env);
874 waitq_put(tmp, tmp_chunk);
875 expand_chunk_from(env, node, visited, tmp_chunk, c, decider, col);
876 assert(ARR_LEN(tmp_chunk->n) > 0 && "No nodes added to chunk");
878 /* remember the local best */
879 aff_chunk_assure_weight(env, tmp_chunk);
880 if (check_for_best && (! best || best->weight < tmp_chunk->weight))
884 assert(best && "No chunk found?");
885 bitset_free(visited);
890 * Resets the temporary fixed color of all nodes within wait queue @p nodes.
891 * ATTENTION: the queue is empty after calling this function!
893 static inline void reject_coloring(struct list_head *nodes) {
894 co_mst_irn_t *n, *temp;
895 DB((dbg, LEVEL_4, "\treject coloring for"));
896 list_for_each_entry_safe(co_mst_irn_t, n, temp, nodes, list) {
897 DB((dbg, LEVEL_4, " %+F", n->irn));
898 assert(n->tmp_col >= 0);
900 list_del_init(&n->list);
902 DB((dbg, LEVEL_4, "\n"));
905 static inline void materialize_coloring(struct list_head *nodes) {
906 co_mst_irn_t *n, *temp;
907 list_for_each_entry_safe(co_mst_irn_t, n, temp, nodes, list) {
908 assert(n->tmp_col >= 0);
911 list_del_init(&n->list);
915 static inline void set_temp_color(co_mst_irn_t *node, int col, struct list_head *changed)
918 assert(!node->fixed);
919 assert(node->tmp_col < 0);
920 assert(node->list.next == &node->list && node->list.prev == &node->list);
921 assert(bitset_is_set(node->adm_colors, col));
923 list_add_tail(&node->list, changed);
927 static inline int is_loose(co_mst_irn_t *node)
929 return !node->fixed && node->tmp_col < 0;
933 * Determines the costs for each color if it would be assigned to node @p node.
935 static void determine_color_costs(co_mst_env_t *env, co_mst_irn_t *node, col_cost_t *costs)
937 int *neigh_cols = ALLOCAN(int, env->n_regs);
942 for (i = 0; i < env->n_regs; ++i) {
945 costs[i].cost = bitset_is_set(node->adm_colors, i) ? node->constr_factor : REAL(0.0);
948 for (i = 0; i < node->n_neighs; ++i) {
949 co_mst_irn_t *n = get_co_mst_irn(env, node->int_neighs[i]);
950 int col = get_mst_irn_col(n);
955 costs[col].cost = REAL(0.0);
959 coeff = REAL(1.0) / n_loose;
960 for (i = 0; i < env->n_regs; ++i)
961 costs[i].cost *= REAL(1.0) - coeff * neigh_cols[i];
965 /* need forward declaration due to recursive call */
966 static int recolor_nodes(co_mst_env_t *env, co_mst_irn_t *node, col_cost_t *costs, struct list_head *changed_ones, int depth, int *max_depth, int *trip);
969 * Tries to change node to a color but @p explude_col.
970 * @return 1 if succeeded, 0 otherwise.
972 static int change_node_color_excluded(co_mst_env_t *env, co_mst_irn_t *node, int exclude_col, struct list_head *changed, int depth, int *max_depth, int *trip) {
973 int col = get_mst_irn_col(node);
976 /* neighbours has already a different color -> good, temporary fix it */
977 if (col != exclude_col) {
979 set_temp_color(node, col, changed);
983 /* The node has the color it should not have _and_ has not been visited yet. */
984 if (is_loose(node)) {
985 col_cost_t *costs = ALLOCAN(col_cost_t, env->n_regs);
987 /* Get the costs for giving the node a specific color. */
988 determine_color_costs(env, node, costs);
990 /* Since the node must not have the not_col, set the costs for that color to "infinity" */
991 costs[exclude_col].cost = REAL(0.0);
993 /* sort the colors according costs, cheapest first. */
994 qsort(costs, env->n_regs, sizeof(costs[0]), cmp_col_cost_gt);
996 /* Try recoloring the node using the color list. */
997 res = recolor_nodes(env, node, costs, changed, depth + 1, max_depth, trip);
1004 * Tries to bring node @p node to cheapest color and color all interfering neighbours with other colors.
1005 * ATTENTION: Expect @p costs already sorted by increasing costs.
1006 * @return 1 if coloring could be applied, 0 otherwise.
1008 static int recolor_nodes(co_mst_env_t *env, co_mst_irn_t *node, col_cost_t *costs, struct list_head *changed, int depth, int *max_depth, int *trip) {
1010 struct list_head local_changed;
1013 if (depth > *max_depth)
1016 DBG((dbg, LEVEL_4, "\tRecoloring %+F with color-costs", node->irn));
1017 DBG_COL_COST(env, LEVEL_4, costs);
1018 DB((dbg, LEVEL_4, "\n"));
1020 if (depth >= recolor_limit) {
1021 DBG((dbg, LEVEL_4, "\tHit recolor limit\n"));
1025 for (i = 0; i < env->n_regs; ++i) {
1026 int tgt_col = costs[i].col;
1030 /* If the costs for that color (and all successive) are infinite, bail out we won't make it anyway. */
1031 if (costs[i].cost == REAL(0.0)) {
1032 DBG((dbg, LEVEL_4, "\tAll further colors forbidden\n"));
1036 /* Set the new color of the node and mark the node as temporarily fixed. */
1037 assert(node->tmp_col < 0 && "Node must not have been temporary fixed.");
1038 INIT_LIST_HEAD(&local_changed);
1039 set_temp_color(node, tgt_col, &local_changed);
1040 DBG((dbg, LEVEL_4, "\tTemporary setting %+F to color %d\n", node->irn, tgt_col));
1042 /* try to color all interfering neighbours with current color forbidden */
1043 for (j = 0; j < node->n_neighs; ++j) {
1047 neigh = node->int_neighs[j];
1049 /* skip ignore nodes */
1050 if (arch_irn_is(neigh, ignore))
1053 nn = get_co_mst_irn(env, neigh);
1054 DB((dbg, LEVEL_4, "\tHandling neighbour %+F, at position %d (fixed: %d, tmp_col: %d, col: %d)\n",
1055 neigh, j, nn->fixed, nn->tmp_col, nn->col));
1058 Try to change the color of the neighbor and record all nodes which
1059 get changed in the tmp list. Add this list to the "changed" list for
1060 that color. If we did not succeed to change the color of the neighbor,
1061 we bail out and try the next color.
1063 if (get_mst_irn_col(nn) == tgt_col) {
1064 /* try to color neighbour with tgt_col forbidden */
1065 neigh_ok = change_node_color_excluded(env, nn, tgt_col, &local_changed, depth + 1, max_depth, trip);
1073 We managed to assign the target color to all neighbors, so from the perspective
1074 of the current node, every thing was ok and we can return safely.
1077 /* append the local_changed ones to global ones */
1078 list_splice(&local_changed, changed);
1082 /* coloring of neighbours failed, so we try next color */
1083 reject_coloring(&local_changed);
1087 DBG((dbg, LEVEL_4, "\tAll colors failed\n"));
1092 * Tries to bring node @p node and all it's neighbours to color @p tgt_col.
1093 * @return 1 if color @p col could be applied, 0 otherwise
1095 static int change_node_color(co_mst_env_t *env, co_mst_irn_t *node, int tgt_col, struct list_head *changed) {
1096 int col = get_mst_irn_col(node);
1098 /* if node already has the target color -> good, temporary fix it */
1099 if (col == tgt_col) {
1100 DBG((dbg, LEVEL_4, "\t\tCNC: %+F has already color %d, fix temporary\n", node->irn, tgt_col));
1102 set_temp_color(node, tgt_col, changed);
1107 Node has not yet a fixed color and target color is admissible
1108 -> try to recolor node and it's affinity neighbours
1110 if (is_loose(node) && bitset_is_set(node->adm_colors, tgt_col)) {
1111 col_cost_t *costs = env->single_cols[tgt_col];
1112 int res, max_depth, trip;
1117 DBG((dbg, LEVEL_4, "\t\tCNC: Attempt to recolor %+F ===>>\n", node->irn));
1118 res = recolor_nodes(env, node, costs, changed, 0, &max_depth, &trip);
1119 DBG((dbg, LEVEL_4, "\t\tCNC: <<=== Recoloring of %+F %s\n", node->irn, res ? "succeeded" : "failed"));
1120 stat_ev_int("heur4_recolor_depth_max", max_depth);
1121 stat_ev_int("heur4_recolor_trip", trip);
1127 #ifdef DEBUG_libfirm
1128 if (firm_dbg_get_mask(dbg) & LEVEL_4) {
1129 if (!is_loose(node))
1130 DB((dbg, LEVEL_4, "\t\tCNC: %+F has already fixed color %d\n", node->irn, col));
1132 DB((dbg, LEVEL_4, "\t\tCNC: color %d not admissible for %+F (", tgt_col, node->irn));
1133 dbg_admissible_colors(env, node);
1134 DB((dbg, LEVEL_4, ")\n"));
1143 * Tries to color an affinity chunk (or at least a part of it).
1144 * Inserts uncolored parts of the chunk as a new chunk into the priority queue.
1146 static void color_aff_chunk(co_mst_env_t *env, aff_chunk_t *c) {
1147 aff_chunk_t *best_chunk = NULL;
1148 int n_nodes = ARR_LEN(c->n);
1149 int best_color = -1;
1150 int n_int_chunks = 0;
1151 waitq *tmp_chunks = new_waitq();
1152 waitq *best_starts = NULL;
1153 col_cost_t *order = ALLOCANZ(col_cost_t, env->n_regs);
1155 int idx, len, i, nidx, pos;
1156 struct list_head changed;
1158 DB((dbg, LEVEL_2, "fragmentizing chunk #%u", c->id));
1159 DBG_AFF_CHUNK(env, LEVEL_2, c);
1160 DB((dbg, LEVEL_2, "\n"));
1162 stat_ev_ctx_push_fmt("heur4_color_chunk", "%u", c->id);
1164 ++env->chunk_visited;
1166 /* compute color preference */
1167 for (pos = 0, len = ARR_LEN(c->interfere); pos < len; ++pos) {
1168 const ir_node *n = c->interfere[pos];
1169 co_mst_irn_t *node = get_co_mst_irn(env, n);
1170 aff_chunk_t *chunk = node->chunk;
1172 if (is_loose(node) && chunk && chunk->visited < env->chunk_visited) {
1173 assert(!chunk->deleted);
1174 chunk->visited = env->chunk_visited;
1177 aff_chunk_assure_weight(env, chunk);
1178 for (i = 0; i < env->n_regs; ++i)
1179 order[i].cost += chunk->color_affinity[i].cost;
1183 for (i = 0; i < env->n_regs; ++i) {
1184 real_t dislike = n_int_chunks > 0 ? REAL(1.0) - order[i].cost / n_int_chunks : REAL(0.0);
1186 order[i].cost = (REAL(1.0) - dislike_influence) * c->color_affinity[i].cost + dislike_influence * dislike;
1189 qsort(order, env->n_regs, sizeof(order[0]), cmp_col_cost_gt);
1191 DBG_COL_COST(env, LEVEL_2, order);
1192 DB((dbg, LEVEL_2, "\n"));
1194 /* check which color is the "best" for the given chunk.
1195 * if we found a color which was ok for all nodes, we take it
1196 * and do not look further. (see did_all flag usage below.)
1197 * If we have many colors which fit all nodes it is hard to decide
1198 * which one to take anyway.
1199 * TODO Sebastian: Perhaps we should at all nodes and figure out
1200 * a suitable color using costs as done above (determine_color_costs).
1202 for (i = 0; i < env->k; ++i) {
1203 int col = order[i].col;
1204 waitq *good_starts = new_waitq();
1205 aff_chunk_t *local_best;
1208 /* skip ignore colors */
1209 if (bitset_is_set(env->ignore_regs, col))
1212 DB((dbg, LEVEL_2, "\ttrying color %d\n", col));
1216 /* try to bring all nodes of given chunk to the current color. */
1217 for (idx = 0, len = ARR_LEN(c->n); idx < len; ++idx) {
1218 const ir_node *irn = c->n[idx];
1219 co_mst_irn_t *node = get_co_mst_irn(env, irn);
1222 assert(! node->fixed && "Node must not have a fixed color.");
1223 DB((dbg, LEVEL_4, "\t\tBringing %+F from color %d to color %d ...\n", irn, node->col, col));
1226 The order of the colored nodes is important, so we record the successfully
1227 colored ones in the order they appeared.
1229 INIT_LIST_HEAD(&changed);
1231 good = change_node_color(env, node, col, &changed);
1232 stat_ev_tim_pop("heur4_recolor");
1234 waitq_put(good_starts, node);
1235 materialize_coloring(&changed);
1240 reject_coloring(&changed);
1242 n_succeeded += good;
1243 DB((dbg, LEVEL_4, "\t\t... %+F attempt from %d to %d %s\n", irn, node->col, col, good ? "succeeded" : "failed"));
1246 /* unfix all nodes */
1247 for (idx = 0, len = ARR_LEN(c->n); idx < len; ++idx) {
1248 co_mst_irn_t *node = get_co_mst_irn(env, c->n[idx]);
1252 /* try next color when failed */
1253 if (n_succeeded == 0)
1256 /* fragment the chunk according to the coloring */
1257 local_best = fragment_chunk(env, col, c, tmp_chunks);
1259 /* search the best of the good list
1260 and make it the new best if it is better than the current */
1262 aff_chunk_assure_weight(env, local_best);
1264 DB((dbg, LEVEL_3, "\t\tlocal best chunk (id %u) for color %d: ", local_best->id, col));
1265 DBG_AFF_CHUNK(env, LEVEL_3, local_best);
1267 if (! best_chunk || best_chunk->weight < local_best->weight) {
1268 best_chunk = local_best;
1271 del_waitq(best_starts);
1272 best_starts = good_starts;
1273 DB((dbg, LEVEL_3, "\n\t\t... setting global best chunk (id %u), color %d\n", best_chunk->id, best_color));
1275 DB((dbg, LEVEL_3, "\n\t\t... omitting, global best is better\n"));
1276 del_waitq(good_starts);
1280 del_waitq(good_starts);
1283 /* if all nodes were recolored, bail out */
1284 if (n_succeeded == n_nodes)
1288 stat_ev_int("heur4_colors_tried", i);
1290 /* free all intermediate created chunks except best one */
1291 while (! waitq_empty(tmp_chunks)) {
1292 aff_chunk_t *tmp = waitq_get(tmp_chunks);
1293 if (tmp != best_chunk)
1294 delete_aff_chunk(env, tmp);
1296 del_waitq(tmp_chunks);
1298 /* return if coloring failed */
1301 del_waitq(best_starts);
1305 DB((dbg, LEVEL_2, "\tbest chunk #%u ", best_chunk->id));
1306 DBG_AFF_CHUNK(env, LEVEL_2, best_chunk);
1307 DB((dbg, LEVEL_2, "using color %d\n", best_color));
1309 for (idx = 0, len = ARR_LEN(best_chunk->n); idx < len; ++idx) {
1310 const ir_node *irn = best_chunk->n[idx];
1311 co_mst_irn_t *node = get_co_mst_irn(env, irn);
1314 /* bring the node to the color. */
1315 DB((dbg, LEVEL_4, "\tManifesting color %d for %+F, chunk #%u\n", best_color, node->irn, best_chunk->id));
1316 INIT_LIST_HEAD(&changed);
1318 res = change_node_color(env, node, best_color, &changed);
1319 stat_ev_tim_pop("heur4_recolor");
1321 materialize_coloring(&changed);
1324 assert(list_empty(&changed));
1327 /* remove the nodes in best chunk from original chunk */
1328 len = ARR_LEN(best_chunk->n);
1329 for (idx = 0; idx < len; ++idx) {
1330 const ir_node *irn = best_chunk->n[idx];
1331 int pos = nodes_bsearch(c->n, irn);
1336 len = ARR_LEN(c->n);
1337 for (idx = nidx = 0; idx < len; ++idx) {
1338 const ir_node *irn = c->n[idx];
1344 ARR_SHRINKLEN(c->n, nidx);
1347 /* we have to get the nodes back into the original chunk because they are scattered over temporary chunks */
1348 for (idx = 0, len = ARR_LEN(c->n); idx < len; ++idx) {
1349 const ir_node *n = c->n[idx];
1350 co_mst_irn_t *nn = get_co_mst_irn(env, n);
1354 /* fragment the remaining chunk */
1355 visited = bitset_irg_malloc(env->co->irg);
1356 for (idx = 0, len = ARR_LEN(best_chunk->n); idx < len; ++idx)
1357 bitset_set(visited, get_irn_idx(best_chunk->n[idx]));
1359 for (idx = 0, len = ARR_LEN(c->n); idx < len; ++idx) {
1360 const ir_node *irn = c->n[idx];
1361 if (! bitset_is_set(visited, get_irn_idx(irn))) {
1362 aff_chunk_t *new_chunk = new_aff_chunk(env);
1363 co_mst_irn_t *node = get_co_mst_irn(env, irn);
1365 expand_chunk_from(env, node, visited, new_chunk, c, decider_always_yes, 0);
1366 aff_chunk_assure_weight(env, new_chunk);
1367 pqueue_put(env->chunks, new_chunk, new_chunk->weight);
1371 for (idx = 0, len = ARR_LEN(best_chunk->n); idx < len; ++idx) {
1372 const ir_node *n = best_chunk->n[idx];
1373 co_mst_irn_t *nn = get_co_mst_irn(env, n);
1377 /* clear obsolete chunks and free some memory */
1378 delete_aff_chunk(env, best_chunk);
1379 bitset_free(visited);
1381 del_waitq(best_starts);
1383 stat_ev_ctx_pop("heur4_color_chunk");
1387 * Main driver for mst safe coalescing algorithm.
1389 int co_solve_heuristic_mst(copy_opt_t *co) {
1390 unsigned n_regs = co->cls->n_regs;
1391 bitset_t *ignore_regs = bitset_alloca(n_regs);
1394 co_mst_env_t mst_env;
1401 phase_init(&mst_env.ph, "co_mst", co->irg, PHASE_DEFAULT_GROWTH, co_mst_irn_init, &mst_env);
1403 k = be_put_ignore_regs(co->cenv->birg, co->cls, ignore_regs);
1406 mst_env.n_regs = n_regs;
1408 mst_env.chunks = new_pqueue();
1410 mst_env.ignore_regs = ignore_regs;
1411 mst_env.ifg = co->cenv->ifg;
1412 mst_env.chunkset = pset_new_ptr(512);
1413 mst_env.chunk_visited = 0;
1414 mst_env.single_cols = phase_alloc(&mst_env.ph, sizeof(*mst_env.single_cols) * n_regs);
1416 for (i = 0; i < n_regs; ++i) {
1417 col_cost_t *vec = phase_alloc(&mst_env.ph, sizeof(*vec) * n_regs);
1419 mst_env.single_cols[i] = vec;
1420 for (j = 0; j < n_regs; ++j) {
1422 vec[j].cost = REAL(0.0);
1426 vec[0].cost = REAL(1.0);
1429 DBG((dbg, LEVEL_1, "==== Coloring %+F, class %s ====\n", co->irg, co->cls->name));
1431 /* build affinity chunks */
1433 build_affinity_chunks(&mst_env);
1434 stat_ev_tim_pop("heur4_initial_chunk");
1436 /* color chunks as long as there are some */
1437 while (! pqueue_empty(mst_env.chunks)) {
1438 aff_chunk_t *chunk = pqueue_pop_front(mst_env.chunks);
1440 color_aff_chunk(&mst_env, chunk);
1441 DB((dbg, LEVEL_4, "<<<====== Coloring chunk (%u) done\n", chunk->id));
1442 delete_aff_chunk(&mst_env, chunk);
1445 /* apply coloring */
1446 foreach_phase_irn(&mst_env.ph, irn) {
1448 const arch_register_t *reg;
1450 if (arch_irn_is(irn, ignore))
1453 mirn = get_co_mst_irn(&mst_env, irn);
1454 // assert(mirn->fixed && "Node should have fixed color");
1456 /* skip nodes where color hasn't changed */
1457 if (mirn->init_col == mirn->col)
1460 reg = arch_register_for_index(co->cls, mirn->col);
1461 arch_set_irn_register(irn, reg);
1462 DB((dbg, LEVEL_1, "%+F set color from %d to %d\n", irn, mirn->init_col, mirn->col));
1465 /* free allocated memory */
1466 del_pqueue(mst_env.chunks);
1467 phase_free(&mst_env.ph);
1468 del_pset(mst_env.chunkset);
1470 stat_ev_tim_pop("heur4_total");
1475 static const lc_opt_table_entry_t options[] = {
1476 LC_OPT_ENT_INT ("limit", "limit recoloring", &recolor_limit),
1477 LC_OPT_ENT_DBL ("di", "dislike influence", &dislike_influence),
1482 void be_init_copyheur4(void) {
1483 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
1484 lc_opt_entry_t *ra_grp = lc_opt_get_grp(be_grp, "ra");
1485 lc_opt_entry_t *chordal_grp = lc_opt_get_grp(ra_grp, "chordal");
1486 lc_opt_entry_t *co_grp = lc_opt_get_grp(chordal_grp, "co");
1487 lc_opt_entry_t *heur4_grp = lc_opt_get_grp(co_grp, "heur4");
1489 lc_opt_add_table(heur4_grp, options);
1490 FIRM_DBG_REGISTER(dbg, "firm.be.co.heur4");
1494 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_copyheur4);