2 * Copyright (C) 1995-2007 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 Primitive list scheduling with different node selectors.
23 * @author Sebastian Hack
43 #include "iredges_t.h"
48 #include "irprintf_t.h"
54 #include "besched_t.h"
57 #include "belistsched.h"
58 #include "beschedmris.h"
59 #include "beschedrss.h"
64 #include <libcore/lc_opts.h>
65 #include <libcore/lc_opts_enum.h>
67 DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL);
69 #define BE_SCHED_NODE(irn) (be_is_Keep(irn) || be_is_CopyKeep(irn) || be_is_RegParams(irn))
72 BE_SCHED_SELECT_TRIVIAL = 0,
73 BE_SCHED_SELECT_REGPRESS = 1,
74 BE_SCHED_SELECT_MUCHNIK = 2,
75 BE_SCHED_SELECT_HEUR = 3,
76 BE_SCHED_SELECT_HMUCHNIK = 4,
77 BE_SCHED_SELECT_RANDOM = 5
81 BE_SCHED_PREP_NONE = 0,
82 BE_SCHED_PREP_MRIS = 2,
86 typedef struct _list_sched_options_t {
87 int select; /**< the node selector */
88 int prep; /**< schedule preparation */
89 } list_sched_options_t;
91 static list_sched_options_t list_sched_options = {
92 BE_SCHED_SELECT_HEUR, /* mueller heuristic selector */
93 BE_SCHED_PREP_NONE, /* no scheduling preparation */
96 /* schedule selector options. */
97 static const lc_opt_enum_int_items_t sched_select_items[] = {
98 { "trivial", BE_SCHED_SELECT_TRIVIAL },
99 { "random", BE_SCHED_SELECT_RANDOM },
100 { "regpress", BE_SCHED_SELECT_REGPRESS },
101 { "muchnik", BE_SCHED_SELECT_MUCHNIK },
102 { "heur", BE_SCHED_SELECT_HEUR },
103 { "hmuchnik", BE_SCHED_SELECT_HMUCHNIK },
107 /* schedule preparation options. */
108 static const lc_opt_enum_int_items_t sched_prep_items[] = {
109 { "none", BE_SCHED_PREP_NONE },
110 { "mris", BE_SCHED_PREP_MRIS },
111 { "rss", BE_SCHED_PREP_RSS },
115 static lc_opt_enum_int_var_t sched_select_var = {
116 &list_sched_options.select, sched_select_items
119 static lc_opt_enum_int_var_t sched_prep_var = {
120 &list_sched_options.prep, sched_prep_items
123 static const lc_opt_table_entry_t list_sched_option_table[] = {
124 LC_OPT_ENT_ENUM_PTR("prep", "schedule preparation", &sched_prep_var),
125 LC_OPT_ENT_ENUM_PTR("select", "node selector", &sched_select_var),
130 * All scheduling info needed per node.
132 typedef struct _sched_irn_t {
133 unsigned num_not_sched_user; /**< The number of not yet scheduled users of this node */
134 unsigned already_sched : 1; /**< Set if this node is already scheduled */
138 * Scheduling environment for the whole graph.
140 typedef struct _sched_env_t {
141 sched_irn_t *sched_info; /**< scheduling info per node */
142 const list_sched_selector_t *selector; /**< The node selector. */
143 const arch_env_t *arch_env; /**< The architecture environment. */
144 const ir_graph *irg; /**< The graph to schedule. */
145 void *selector_env; /**< A pointer to give to the selector. */
149 * Environment for a block scheduler.
151 typedef struct _block_sched_env_t {
152 sched_irn_t *sched_info; /**< scheduling info per node, copied from the global scheduler object */
153 ir_nodeset_t cands; /**< the set of candidates */
154 ir_node *block; /**< the current block */
155 sched_env_t *sched_env; /**< the scheduler environment */
156 ir_nodeset_t live; /**< simple liveness during scheduling */
157 const list_sched_selector_t *selector;
158 void *selector_block_env;
162 * Returns non-zero if a node must be placed in the schedule.
164 static INLINE int must_appear_in_schedule(const list_sched_selector_t *sel, void *block_env, const ir_node *irn)
168 /* if there are no uses, don't schedule */
169 if (get_irn_n_edges(irn) < 1)
172 /* else ask the scheduler */
173 if (sel->to_appear_in_schedule)
174 res = sel->to_appear_in_schedule(block_env, irn);
176 return res >= 0 ? res : ((to_appear_in_schedule(irn) || BE_SCHED_NODE(irn)) && ! is_Unknown(irn));
180 * Returns non-zero if the node is already scheduled
182 static INLINE int is_already_scheduled(block_sched_env_t *env, ir_node *n)
184 int idx = get_irn_idx(n);
186 assert(idx < ARR_LEN(env->sched_info));
187 return env->sched_info[idx].already_sched;
191 * Mark a node as already scheduled
193 static INLINE void set_already_scheduled(block_sched_env_t *env, ir_node *n)
195 int idx = get_irn_idx(n);
197 assert(idx < ARR_LEN(env->sched_info));
198 env->sched_info[idx].already_sched = 1;
201 static void add_to_sched(block_sched_env_t *env, ir_node *irn);
204 * Try to put a node in the ready set.
205 * @param env The block scheduler environment.
206 * @param pred The previous scheduled node.
207 * @param irn The node to make ready.
208 * @return 1, if the node could be made ready, 0 else.
210 static INLINE int make_ready(block_sched_env_t *env, ir_node *pred, ir_node *irn)
214 /* Blocks cannot be scheduled. */
215 if (is_Block(irn) || get_irn_n_edges(irn) == 0)
219 * Check, if the given ir node is in a different block as the
220 * currently scheduled one. If that is so, don't make the node ready.
222 if (env->block != get_nodes_block(irn))
225 for (i = 0, n = get_irn_ins_or_deps(irn); i < n; ++i) {
226 ir_node *op = get_irn_in_or_dep(irn, i);
228 /* if irn is an End we have keep-alives and op might be a block, skip that */
230 assert(get_irn_op(irn) == op_End);
234 /* If the operand is local to the scheduled block and not yet
235 * scheduled, this nodes cannot be made ready, so exit. */
236 if (! is_already_scheduled(env, op) && get_nodes_block(op) == env->block)
240 if (! must_appear_in_schedule(env->selector, env, irn)) {
241 add_to_sched(env, irn);
242 DB((dbg, LEVEL_3, "\tmaking immediately available: %+F\n", irn));
244 ir_nodeset_insert(&env->cands, irn);
246 /* Notify selector about the ready node. */
247 if (env->selector->node_ready)
248 env->selector->node_ready(env->selector_block_env, irn, pred);
250 DB((dbg, LEVEL_2, "\tmaking ready: %+F\n", irn));
257 * Try, to make all users of a node ready.
258 * In fact, a usage node can only be made ready, if all its operands
259 * have already been scheduled yet. This is checked by make_ready().
260 * @param env The block schedule environment.
261 * @param irn The node, which usages (successors) are to be made ready.
263 static void make_users_ready(block_sched_env_t *env, ir_node *irn)
265 const ir_edge_t *edge;
267 /* make all data users ready */
268 foreach_out_edge(irn, edge) {
269 ir_node *user = get_edge_src_irn(edge);
272 make_ready(env, irn, user);
275 /* and the dependent nodes as well */
276 foreach_out_edge_kind(irn, edge, EDGE_KIND_DEP) {
277 ir_node *user = get_edge_src_irn(edge);
280 make_ready(env, irn, user);
285 * Returns the number of not yet schedules users.
287 static INLINE int get_irn_not_sched_user(block_sched_env_t *env, ir_node *n) {
288 int idx = get_irn_idx(n);
290 assert(idx < ARR_LEN(env->sched_info));
291 return env->sched_info[idx].num_not_sched_user;
295 * Sets the number of not yet schedules users.
297 static INLINE void set_irn_not_sched_user(block_sched_env_t *env, ir_node *n, int num) {
298 int idx = get_irn_idx(n);
300 assert(idx < ARR_LEN(env->sched_info));
301 env->sched_info[idx].num_not_sched_user = num;
305 * Add @p num to the number of not yet schedules users and returns the result.
307 static INLINE int add_irn_not_sched_user(block_sched_env_t *env, ir_node *n, int num) {
308 int idx = get_irn_idx(n);
310 assert(idx < ARR_LEN(env->sched_info));
311 env->sched_info[idx].num_not_sched_user += num;
312 return env->sched_info[idx].num_not_sched_user;
316 * Returns the number of users of a node having mode datab.
318 static int get_num_successors(ir_node *irn) {
320 const ir_edge_t *edge;
322 if (get_irn_mode(irn) == mode_T) {
323 /* for mode_T nodes: count the users of all Projs */
324 foreach_out_edge(irn, edge) {
325 ir_node *proj = get_edge_src_irn(edge);
326 ir_mode *mode = get_irn_mode(proj);
328 if (mode == mode_T) {
329 sum += get_num_successors(proj);
330 } else if (mode_is_datab(mode)) {
331 sum += get_irn_n_edges(proj);
336 /* do not count keep-alive edges */
337 foreach_out_edge(irn, edge) {
338 if (get_irn_opcode(get_edge_src_irn(edge)) != iro_End)
347 * Adds irn to @p live, updates all inputs that this user is scheduled
348 * and counts all of its non scheduled users.
350 static void update_sched_liveness(block_sched_env_t *env, ir_node *irn) {
357 for (i = get_irn_ins_or_deps(irn) - 1; i >= 0; --i) {
358 ir_node *in = get_irn_in_or_dep(irn, i);
360 /* if in is a proj: update predecessor */
363 /* if in is still in the live set: reduce number of users by one */
364 if (ir_nodeset_contains(&env->live, in)) {
365 if (add_irn_not_sched_user(env, in, -1) <= 0)
366 ir_nodeset_remove(&env->live, in);
371 get_num_successors returns the number of all users. This includes
372 users in different blocks as well. As the each block is scheduled separately
373 the liveness info of those users will not be updated and so these
374 users will keep up the register pressure as it is desired.
376 i = get_num_successors(irn);
378 set_irn_not_sched_user(env, irn, i);
379 ir_nodeset_insert(&env->live, irn);
384 * Append an instruction to a schedule.
385 * @param env The block scheduling environment.
386 * @param irn The node to add to the schedule.
387 * @return The given node.
389 static void add_to_sched(block_sched_env_t *env, ir_node *irn)
391 /* If the node consumes/produces data, it is appended to the schedule
392 * list, otherwise, it is not put into the list */
393 if (must_appear_in_schedule(env->selector, env->selector_block_env, irn)) {
394 update_sched_liveness(env, irn);
395 sched_add_before(env->block, irn);
397 DBG((dbg, LEVEL_2, "\tadding %+F\n", irn));
399 /* Remove the node from the ready set */
400 ir_nodeset_remove(&env->cands, irn);
403 /* notify the selector about the finally selected node. */
404 if (env->selector->node_selected)
405 env->selector->node_selected(env->selector_block_env, irn);
407 /* Insert the node in the set of all available scheduled nodes. */
408 set_already_scheduled(env, irn);
410 make_users_ready(env, irn);
414 * Perform list scheduling on a block.
416 * Note, that the caller must compute a linked list of nodes in the block
417 * using the link field before calling this function.
419 * Also the outs must have been computed.
421 * @param block The block node.
422 * @param env Scheduling environment.
424 static void list_sched_block(ir_node *block, void *env_ptr)
426 sched_env_t *env = env_ptr;
427 const list_sched_selector_t *selector = env->selector;
428 ir_node *start_node = get_irg_start(get_irn_irg(block));
430 block_sched_env_t be;
431 const ir_edge_t *edge;
435 /* Initialize the block's list head that will hold the schedule. */
436 sched_init_block(block);
438 /* Initialize the block scheduling environment */
439 be.sched_info = env->sched_info;
441 ir_nodeset_init_size(&be.cands, get_irn_n_edges(block));
442 ir_nodeset_init_size(&be.live, get_irn_n_edges(block));
443 be.selector = selector;
446 DBG((dbg, LEVEL_1, "scheduling %+F\n", block));
448 if (selector->init_block)
449 be.selector_block_env = selector->init_block(env->selector_env, block);
451 /* Then one can add all nodes are ready to the set. */
452 foreach_out_edge(block, edge) {
453 ir_node *irn = get_edge_src_irn(edge);
455 /* Skip the end node because of keepalive edges. */
456 if (get_irn_opcode(irn) == iro_End)
459 if (get_irn_n_edges(irn) == 0)
464 Phi functions are scheduled immediately, since they only
465 transfer data flow from the predecessors to this block.
467 add_to_sched(&be, irn);
469 else if (irn == start_node) {
470 /* The start block will be scheduled as the first node */
471 add_to_sched(&be, irn);
472 #ifdef SCHEDULE_PROJS
473 add_tuple_projs(&be, irn);
477 /* Other nodes must have all operands in other blocks to be made
481 /* Check, if the operands of a node are not local to this block */
482 for (j = 0, m = get_irn_ins_or_deps(irn); j < m; ++j) {
483 ir_node *operand = get_irn_in_or_dep(irn, j);
485 if (get_nodes_block(operand) == block) {
489 /* live in values increase register pressure */
490 ir_nodeset_insert(&be.live, operand);
494 /* Make the node ready, if all operands live in a foreign block */
496 DBG((dbg, LEVEL_2, "\timmediately ready: %+F\n", irn));
497 make_ready(&be, NULL, irn);
502 /* Iterate over all remaining nodes */
503 while (ir_nodeset_size(&be.cands) > 0) {
504 ir_nodeset_iterator_t iter;
505 /* collect statistics about amount of ready nodes */
506 be_do_stat_sched_ready(block, &be.cands);
508 /* Keeps must be scheduled immediately */
509 foreach_ir_nodeset(&be.cands, irn, iter) {
510 if (be_is_Keep(irn) || be_is_CopyKeep(irn) || is_Sync(irn)) {
516 /* Keeps must be immediately scheduled */
517 irn = be.selector->select(be.selector_block_env, &be.cands, &be.live);
520 DB((dbg, LEVEL_2, "\tpicked node %+F\n", irn));
522 /* Add the node to the schedule. */
523 add_to_sched(&be, irn);
525 /* remove the scheduled node from the ready list. */
526 ir_nodeset_remove(&be.cands, irn);
529 if (selector->finish_block)
530 selector->finish_block(be.selector_block_env);
532 ir_nodeset_destroy(&be.cands);
533 ir_nodeset_destroy(&be.live);
536 /* List schedule a graph. */
537 void list_sched(be_irg_t *birg, be_options_t *be_opts)
539 const arch_env_t *arch_env = birg->main_env->arch_env;
540 ir_graph *irg = birg->irg;
544 mris_env_t *mris = NULL;
545 list_sched_selector_t sel;
549 /* Select a scheduler based on backend options */
550 switch (list_sched_options.select) {
551 case BE_SCHED_SELECT_TRIVIAL:
552 memcpy(&sel, trivial_selector, sizeof(sel));
554 case BE_SCHED_SELECT_RANDOM:
555 memcpy(&sel, random_selector, sizeof(sel));
557 case BE_SCHED_SELECT_REGPRESS:
558 memcpy(&sel, reg_pressure_selector, sizeof(sel));
560 case BE_SCHED_SELECT_MUCHNIK:
561 memcpy(&sel, muchnik_selector, sizeof(sel));
563 case BE_SCHED_SELECT_HEUR:
564 memcpy(&sel, heuristic_selector, sizeof(sel));
566 case BE_SCHED_SELECT_HMUCHNIK:
568 memcpy(&sel, trivial_selector, sizeof(sel));
572 /* Matze: This is very slow, we should avoid it to improve backend speed,
573 * we just have to make sure that we have no dangling out-edges at this
577 /* Assure, that we have no dangling out-edges to deleted stuff */
578 edges_deactivate(birg->irg);
579 edges_activate(birg->irg);
582 switch (list_sched_options.prep) {
583 case BE_SCHED_PREP_MRIS:
584 mris = be_sched_mris_preprocess(birg);
586 case BE_SCHED_PREP_RSS:
587 rss_schedule_preparation(birg);
593 num_nodes = get_irg_last_idx(irg);
595 /* initialize environment for list scheduler */
596 memset(&env, 0, sizeof(env));
597 env.selector = arch_env->isa->impl->get_list_sched_selector(arch_env->isa, &sel);
598 env.arch_env = arch_env;
600 env.sched_info = NEW_ARR_F(sched_irn_t, num_nodes);
602 memset(env.sched_info, 0, num_nodes * sizeof(env.sched_info[0]));
604 if (env.selector->init_graph)
605 env.selector_env = env.selector->init_graph(env.selector, arch_env, irg);
607 /* Schedule each single block. */
608 irg_block_walk_graph(irg, list_sched_block, NULL, &env);
610 if (env.selector->finish_graph)
611 env.selector->finish_graph(env.selector_env);
613 if (list_sched_options.prep == BE_SCHED_PREP_MRIS)
614 be_sched_mris_free(mris);
616 DEL_ARR_F(env.sched_info);
619 /* List schedule a block. */
620 void list_sched_single_block(const be_irg_t *birg, ir_node *block,
621 be_options_t *be_opts)
623 const arch_env_t *arch_env = birg->main_env->arch_env;
624 ir_graph *irg = birg->irg;
628 list_sched_selector_t sel;
632 /* Select a scheduler based on backend options */
633 switch (list_sched_options.select) {
634 case BE_SCHED_SELECT_TRIVIAL:
635 memcpy(&sel, trivial_selector, sizeof(sel));
637 case BE_SCHED_SELECT_RANDOM:
638 memcpy(&sel, random_selector, sizeof(sel));
640 case BE_SCHED_SELECT_REGPRESS:
641 memcpy(&sel, reg_pressure_selector, sizeof(sel));
643 case BE_SCHED_SELECT_MUCHNIK:
644 memcpy(&sel, muchnik_selector, sizeof(sel));
646 case BE_SCHED_SELECT_HEUR:
647 memcpy(&sel, heuristic_selector, sizeof(sel));
649 case BE_SCHED_SELECT_HMUCHNIK:
651 memcpy(&sel, trivial_selector, sizeof(sel));
654 /* Assure, that the out edges are computed */
655 edges_deactivate(birg->irg);
656 edges_activate(birg->irg);
658 num_nodes = get_irg_last_idx(irg);
660 /* initialize environment for list scheduler */
661 memset(&env, 0, sizeof(env));
662 env.selector = arch_env->isa->impl->get_list_sched_selector(arch_env->isa, &sel);
663 env.arch_env = arch_env;
665 env.sched_info = NEW_ARR_F(sched_irn_t, num_nodes);
667 memset(env.sched_info, 0, num_nodes * sizeof(env.sched_info[0]));
669 if (env.selector->init_graph)
670 env.selector_env = env.selector->init_graph(env.selector, arch_env, irg);
672 /* Schedule block. */
673 list_sched_block(block, &env);
675 if (env.selector->finish_graph)
676 env.selector->finish_graph(env.selector_env);
678 DEL_ARR_F(env.sched_info);
682 * Register list scheduler options.
684 void be_init_listsched(void) {
685 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
686 lc_opt_entry_t *sched_grp = lc_opt_get_grp(be_grp, "listsched");
688 lc_opt_add_table(sched_grp, list_sched_option_table);
690 FIRM_DBG_REGISTER(dbg, "firm.be.sched");
693 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_listsched);