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 Chordal register allocation.
23 * @author Sebastian Hack
37 #include "raw_bitset.h"
39 #include "bipartite.h"
40 #include "hungarian.h"
43 #include "irgraph_t.h"
44 #include "irprintf_t.h"
56 #include "besched_t.h"
63 #include "bestatevent.h"
65 #include "beintlive_t.h"
67 #include "bechordal_t.h"
68 #include "bechordal_draw.h"
71 DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
75 #define DUMP_INTERVALS
77 /* new style assign routine without borders. */
78 #undef NEW_STYLE_ASSIGN
80 typedef struct _be_chordal_alloc_env_t {
81 be_chordal_env_t *chordal_env;
83 pset *pre_colored; /**< Set of precolored nodes. */
84 bitset_t *live; /**< A liveness bitset. */
85 bitset_t *tmp_colors; /**< An auxiliary bitset which is as long as the number of colors in the class. */
86 bitset_t *colors; /**< The color mask. */
87 bitset_t *in_colors; /**< Colors used by live in values. */
88 int colors_n; /**< The number of colors. */
89 } be_chordal_alloc_env_t;
93 /* Make a fourcc for border checking. */
94 #define BORDER_FOURCC FOURCC('B', 'O', 'R', 'D')
97 static void check_border_list(struct list_head *head)
100 list_for_each_entry(border_t, x, head, list) {
101 assert(x->magic == BORDER_FOURCC);
105 static void check_heads(be_chordal_env_t *env)
108 for(ent = pmap_first(env->border_heads); ent; ent = pmap_next(env->border_heads)) {
109 /* ir_printf("checking border list of block %+F\n", ent->key); */
110 check_border_list(ent->value);
116 * Add an interval border to the list of a block's list
117 * of interval border.
118 * @note You always have to create the use before the def.
119 * @param env The environment.
120 * @param head The list head to enqueue the borders.
121 * @param irn The node (value) the border belongs to.
122 * @param pressure The pressure at this point in time.
123 * @param step A time step for the border.
124 * @param is_def Is the border a use or a def.
125 * @return The created border.
127 static INLINE border_t *border_add(be_chordal_env_t *env, struct list_head *head,
128 ir_node *irn, unsigned step, unsigned pressure,
129 unsigned is_def, unsigned is_real)
136 b = obstack_alloc(env->obst, sizeof(*b));
138 /* also allocate the def and tie it to the use. */
139 def = obstack_alloc(env->obst, sizeof(*def));
140 memset(def, 0, sizeof(*def));
145 * Set the link field of the irn to the def.
146 * This strongly relies on the fact, that the use is always
147 * made before the def.
149 set_irn_link(irn, def);
151 DEBUG_ONLY(b->magic = BORDER_FOURCC);
152 DEBUG_ONLY(def->magic = BORDER_FOURCC);
156 * If the def is encountered, the use was made and so was the
157 * the def node (see the code above). It was placed into the
158 * link field of the irn, so we can get it there.
161 b = get_irn_link(irn);
163 assert(b && b->magic == BORDER_FOURCC && "Illegal border encountered");
166 b->pressure = pressure;
168 b->is_real = is_real;
171 list_add_tail(&b->list, head);
172 DBG((dbg, LEVEL_5, "\t\t%s adding %+F, step: %d\n", is_def ? "def" : "use", irn, step));
179 * Check, if an irn is of the register class currently under processing.
180 * @param env The chordal environment.
181 * @param irn The node.
182 * @return 1, if the node is of that register class, 0 if not.
184 static INLINE int has_reg_class(const be_chordal_env_t *env, const ir_node *irn)
186 return arch_irn_consider_in_reg_alloc(env->birg->main_env->arch_env, env->cls, irn);
189 #define has_limited_constr(req, irn) \
190 (arch_get_register_req(arch_env, (req), irn, -1) && (req)->type == arch_register_req_type_limited)
192 static int get_next_free_reg(const be_chordal_alloc_env_t *alloc_env, bitset_t *colors)
194 bitset_t *tmp = alloc_env->tmp_colors;
195 bitset_copy(tmp, colors);
196 bitset_or(tmp, alloc_env->chordal_env->ignore_colors);
197 return bitset_next_clear(tmp, 0);
200 static bitset_t *get_decisive_partner_regs(bitset_t *bs, const be_operand_t *o1, const be_operand_t *o2)
205 bitset_copy(bs, o2->regs);
210 bitset_copy(bs, o1->regs);
214 assert(o1->req->cls == o2->req->cls || ! o1->req->cls || ! o2->req->cls);
216 if(bitset_contains(o1->regs, o2->regs))
217 bitset_copy(bs, o1->regs);
218 else if(bitset_contains(o2->regs, o1->regs))
219 bitset_copy(bs, o2->regs);
226 static be_insn_t *chordal_scan_insn(be_chordal_env_t *env, ir_node *irn)
230 ie.ignore_colors = env->ignore_colors;
231 ie.aenv = env->birg->main_env->arch_env;
234 return be_scan_insn(&ie, irn);
237 static ir_node *prepare_constr_insn(be_chordal_env_t *env, ir_node *irn)
239 const be_irg_t *birg = env->birg;
240 const arch_env_t *aenv = birg->main_env->arch_env;
241 bitset_t *tmp = bitset_alloca(env->cls->n_regs);
242 bitset_t *def_constr = bitset_alloca(env->cls->n_regs);
243 ir_node *bl = get_nodes_block(irn);
244 be_lv_t *lv = env->birg->lv;
249 for (i = get_irn_arity(irn) - 1; i >= 0; --i) {
250 ir_node *op = get_irn_n(irn, i);
252 const arch_register_t *reg;
253 const arch_register_req_t *req;
255 if (arch_get_irn_reg_class(aenv, irn, i) != env->cls)
258 reg = arch_get_irn_register(aenv, op);
260 if (reg == NULL || !arch_register_type_is(reg, ignore))
262 if(arch_register_type_is(reg, joker))
265 req = arch_get_register_req(aenv, irn, i);
266 if (!arch_register_req_is(req, limited))
269 if (rbitset_is_set(req->limited, reg->index))
272 copy = be_new_Copy(env->cls, env->irg, bl, op);
273 be_stat_ev("constr_copy", 1);
275 sched_add_before(irn, copy);
276 set_irn_n(irn, i, copy);
277 DBG((dbg, LEVEL_3, "inserting ignore arg copy %+F for %+F pos %d\n", copy, irn, i));
280 insn = chordal_scan_insn(env, irn);
282 if(!insn->has_constraints)
285 /* insert copies for nodes that occur constrained more than once. */
286 for(i = insn->use_start; i < insn->n_ops; ++i) {
287 be_operand_t *op = &insn->ops[i];
289 if(!op->has_constraints)
292 for(j = i + 1; j < insn->n_ops; ++j) {
294 be_operand_t *a_op = &insn->ops[j];
296 if(a_op->carrier != op->carrier || !a_op->has_constraints)
299 if (be_is_Copy(get_irn_n(insn->irn, a_op->pos)))
302 copy = be_new_Copy(env->cls, env->irg, bl, op->carrier);
303 be_stat_ev("constr_copy", 1);
305 sched_add_before(insn->irn, copy);
306 set_irn_n(insn->irn, a_op->pos, copy);
307 DBG((dbg, LEVEL_3, "inserting multiple constr copy %+F for %+F pos %d\n", copy, insn->irn, a_op->pos));
311 /* collect all registers occuring in out constraints. */
312 for(i = 0; i < insn->use_start; ++i) {
313 be_operand_t *op = &insn->ops[i];
314 if(op->has_constraints)
315 bitset_or(def_constr, op->regs);
319 insert copies for all constrained arguments living through the node
320 and being constrained to a register which also occurs in out constraints.
322 for(i = insn->use_start; i < insn->n_ops; ++i) {
324 be_operand_t *op = &insn->ops[i];
326 bitset_copy(tmp, op->regs);
327 bitset_and(tmp, def_constr);
331 1) the operand is constrained.
332 2) lives through the node.
333 3) is constrained to a register occuring in out constraints.
335 if(!op->has_constraints ||
336 !values_interfere(birg, insn->irn, op->carrier) ||
337 bitset_popcnt(tmp) == 0)
341 only create the copy if the operand is no copy.
342 this is necessary since the assure constraints phase inserts
343 Copies and Keeps for operands which must be different from the
344 results. Additional copies here would destroy this.
346 if (be_is_Copy(get_irn_n(insn->irn, op->pos)))
349 copy = be_new_Copy(env->cls, env->irg, bl, op->carrier);
351 sched_add_before(insn->irn, copy);
352 set_irn_n(insn->irn, op->pos, copy);
353 DBG((dbg, LEVEL_3, "inserting constr copy %+F for %+F pos %d\n", copy, insn->irn, op->pos));
354 be_liveness_update(lv, op->carrier);
358 obstack_free(env->obst, insn);
359 return insn->next_insn;
362 static void pre_spill_prepare_constr_walker(ir_node *bl, void *data)
364 be_chordal_env_t *env = data;
366 for(irn = sched_first(bl); !sched_is_end(irn);) {
367 irn = prepare_constr_insn(env, irn);
371 void be_pre_spill_prepare_constr(be_chordal_env_t *cenv) {
372 irg_block_walk_graph(cenv->irg, pre_spill_prepare_constr_walker, NULL, (void *) cenv);
375 static void pair_up_operands(const be_chordal_alloc_env_t *alloc_env, be_insn_t *insn)
377 const be_chordal_env_t *env = alloc_env->chordal_env;
379 int n_uses = be_insn_n_uses(insn);
380 int n_defs = be_insn_n_defs(insn);
381 bitset_t *bs = bitset_alloca(env->cls->n_regs);
382 int *pairing = alloca(MAX(n_defs, n_uses) * sizeof(pairing[0]));
387 For each out operand, try to find an in operand which can be assigned the
388 same register as the out operand.
390 for (j = 0; j < insn->use_start; ++j) {
392 int smallest_n_regs = 2 * env->cls->n_regs + 1;
393 be_operand_t *out_op = &insn->ops[j];
395 /* Try to find an in operand which has ... */
396 for(i = insn->use_start; i < insn->n_ops; ++i) {
398 const be_operand_t *op = &insn->ops[i];
400 if (op->partner != NULL)
402 if (values_interfere(env->birg, op->irn, op->carrier))
405 bitset_clear_all(bs);
406 bitset_copy(bs, op->regs);
407 bitset_and(bs, out_op->regs);
408 n_total = bitset_popcnt(op->regs) + bitset_popcnt(out_op->regs);
410 if (bitset_popcnt(bs) > 0 && n_total < smallest_n_regs) {
412 smallest_n_regs = n_total;
417 be_operand_t *partner = &insn->ops[smallest];
419 for(i = insn->use_start; i < insn->n_ops; ++i) {
420 if(insn->ops[i].carrier == partner->carrier)
421 insn->ops[i].partner = out_op;
424 out_op->partner = partner;
425 partner->partner = out_op;
431 static ir_node *pre_process_constraints(be_chordal_alloc_env_t *alloc_env,
432 be_insn_t **the_insn)
434 be_chordal_env_t *env = alloc_env->chordal_env;
435 const arch_env_t *aenv = env->birg->main_env->arch_env;
436 be_insn_t *insn = *the_insn;
437 ir_node *perm = NULL;
438 bitset_t *out_constr = bitset_alloca(env->cls->n_regs);
439 const ir_edge_t *edge;
442 assert(insn->has_constraints && "only do this for constrained nodes");
445 Collect all registers that occur in output constraints.
446 This is necessary, since if the insn has one of these as an input constraint
447 and the corresponding operand interferes with the insn, the operand must
450 for(i = 0; i < insn->use_start; ++i) {
451 be_operand_t *op = &insn->ops[i];
452 if(op->has_constraints)
453 bitset_or(out_constr, op->regs);
457 Make the Perm, recompute liveness and re-scan the insn since the
458 in operands are now the Projs of the Perm.
460 perm = insert_Perm_after(env->birg, env->cls, sched_prev(insn->irn));
462 /* Registers are propagated by insert_Perm_after(). Clean them here! */
466 be_stat_ev("constr_perm", get_irn_arity(perm));
467 foreach_out_edge(perm, edge) {
468 ir_node *proj = get_edge_src_irn(edge);
469 arch_set_irn_register(aenv, proj, NULL);
473 We also have to re-build the insn since the input operands are now the Projs of
474 the Perm. Recomputing liveness is also a good idea if a Perm is inserted, since
475 the live sets may change.
477 // be_liveness_recompute(lv);
478 obstack_free(env->obst, insn);
479 *the_insn = insn = chordal_scan_insn(env, insn->irn);
482 Copy the input constraints of the insn to the Perm as output
483 constraints. Succeeding phases (coalescing) will need that.
485 for(i = insn->use_start; i < insn->n_ops; ++i) {
486 be_operand_t *op = &insn->ops[i];
487 ir_node *proj = op->carrier;
489 Note that the predecessor must not be a Proj of the Perm,
490 since ignore-nodes are not Perm'ed.
492 if(op->has_constraints && is_Proj(proj) && get_Proj_pred(proj) == perm) {
493 be_set_constr_limited(perm, BE_OUT_POS(get_Proj_proj(proj)), op->req);
500 static ir_node *handle_constraints(be_chordal_alloc_env_t *alloc_env,
501 ir_node *irn, int *silent)
503 const arch_env_t *aenv;
506 ir_node **alloc_nodes;
507 //hungarian_problem_t *bp;
512 const ir_edge_t *edge;
513 ir_node *perm = NULL;
515 be_chordal_env_t *env = alloc_env->chordal_env;
516 void *base = obstack_base(env->obst);
517 be_insn_t *insn = chordal_scan_insn(env, irn);
518 ir_node *res = insn->next_insn;
519 int be_silent = *silent;
520 be_irg_t *birg = env->birg;
523 if(insn->pre_colored) {
525 for(i = 0; i < insn->use_start; ++i)
526 pset_insert_ptr(alloc_env->pre_colored, insn->ops[i].carrier);
530 If the current node is a barrier toggle the silent flag.
531 If we are in the start block, we are ought to be silent at the beginning,
532 so the toggling activates the constraint handling but skips the barrier.
533 If we are in the end block we handle the in requirements of the barrier
534 and set the rest to silent.
536 if(be_is_Barrier(irn))
543 Perms inserted before the constraint handling phase are considered to be
544 correctly precolored. These Perms arise during the ABI handling phase.
546 if(!insn->has_constraints)
549 aenv = env->birg->main_env->arch_env;
550 n_regs = env->cls->n_regs;
551 bs = bitset_alloca(n_regs);
552 alloc_nodes = alloca(n_regs * sizeof(alloc_nodes[0]));
553 //bp = hungarian_new(n_regs, n_regs, 2, HUNGARIAN_MATCH_PERFECT);
554 bp = bipartite_new(n_regs, n_regs);
555 assignment = alloca(n_regs * sizeof(assignment[0]));
556 partners = pmap_create();
559 prepare the constraint handling of this node.
560 Perms are constructed and Copies are created for constrained values
561 interfering with the instruction.
563 perm = pre_process_constraints(alloc_env, &insn);
565 /* find suitable in operands to the out operands of the node. */
566 pair_up_operands(alloc_env, insn);
569 look at the in/out operands and add each operand (and its possible partner)
570 to a bipartite graph (left: nodes with partners, right: admissible colors).
572 for(i = 0, n_alloc = 0; i < insn->n_ops; ++i) {
573 be_operand_t *op = &insn->ops[i];
576 If the operand has no partner or the partner has not been marked
577 for allocation, determine the admissible registers and mark it
578 for allocation by associating the node and its partner with the
579 set of admissible registers via a bipartite graph.
581 if(!op->partner || !pmap_contains(partners, op->partner->carrier)) {
582 ir_node *partner = op->partner ? op->partner->carrier : NULL;
585 pmap_insert(partners, op->carrier, partner);
587 pmap_insert(partners, partner, op->carrier);
589 /* don't insert a node twice */
590 for(i = 0; i < n_alloc; ++i) {
591 if(alloc_nodes[i] == op->carrier) {
598 alloc_nodes[n_alloc] = op->carrier;
600 DBG((dbg, LEVEL_2, "\tassociating %+F and %+F\n", op->carrier,
603 bitset_clear_all(bs);
604 get_decisive_partner_regs(bs, op, op->partner);
606 DBG((dbg, LEVEL_2, "\tallowed registers for %+F: %B\n", op->carrier,
609 bitset_foreach(bs, col) {
610 //hungarian_add(bp, n_alloc, col, 1);
611 bipartite_add(bp, n_alloc, col);
619 Put all nodes which live through the constrained instruction also to the
620 allocation bipartite graph. They are considered unconstrained.
623 foreach_out_edge(perm, edge) {
625 ir_node *proj = get_edge_src_irn(edge);
627 assert(is_Proj(proj));
629 if(!values_interfere(birg, proj, irn) || pmap_contains(partners, proj))
632 /* don't insert a node twice */
633 for(i = 0; i < n_alloc; ++i) {
634 if(alloc_nodes[i] == proj) {
642 assert(n_alloc < n_regs);
644 alloc_nodes[n_alloc] = proj;
645 pmap_insert(partners, proj, NULL);
647 bitset_clear_all(bs);
648 arch_put_non_ignore_regs(aenv, env->cls, bs);
649 bitset_andnot(bs, env->ignore_colors);
650 bitset_foreach(bs, col) {
651 //hungarian_add(bp, n_alloc, col, 1);
652 bipartite_add(bp, n_alloc, col);
659 /* Compute a valid register allocation. */
661 hungarian_prepare_cost_matrix(bp, HUNGARIAN_MODE_MAXIMIZE_UTIL);
662 match_res = hungarian_solve(bp, assignment, &cost, 1);
663 assert(match_res == 0 && "matching failed");
665 bipartite_matching(bp, assignment);
668 /* Assign colors obtained from the matching. */
669 for(i = 0; i < n_alloc; ++i) {
670 const arch_register_t *reg;
674 assert(assignment[i] >= 0 && "there must have been a register assigned");
675 reg = arch_register_for_index(env->cls, assignment[i]);
677 nodes[0] = alloc_nodes[i];
678 nodes[1] = pmap_get(partners, alloc_nodes[i]);
680 for(j = 0; j < 2; ++j) {
684 assert(! (reg->type & arch_register_type_ignore));
685 arch_set_irn_register(aenv, nodes[j], reg);
686 (void) pset_hinsert_ptr(alloc_env->pre_colored, nodes[j]);
687 DBG((dbg, LEVEL_2, "\tsetting %+F to register %s\n", nodes[j], reg->name));
691 /* Allocate the non-constrained Projs of the Perm. */
693 bitset_clear_all(bs);
695 /* Put the colors of all Projs in a bitset. */
696 foreach_out_edge(perm, edge) {
697 ir_node *proj = get_edge_src_irn(edge);
698 const arch_register_t *reg = arch_get_irn_register(aenv, proj);
701 bitset_set(bs, reg->index);
704 /* Assign the not yet assigned Projs of the Perm a suitable color. */
705 foreach_out_edge(perm, edge) {
706 ir_node *proj = get_edge_src_irn(edge);
707 const arch_register_t *reg = arch_get_irn_register(aenv, proj);
709 DBG((dbg, LEVEL_2, "\tchecking reg of %+F: %s\n", proj, reg ? reg->name : "<none>"));
712 col = get_next_free_reg(alloc_env, bs);
713 reg = arch_register_for_index(env->cls, col);
714 bitset_set(bs, reg->index);
715 arch_set_irn_register(aenv, proj, reg);
716 pset_insert_ptr(alloc_env->pre_colored, proj);
717 DBG((dbg, LEVEL_2, "\tsetting %+F to register %s\n", proj, reg->name));
723 //hungarian_free(bp);
724 pmap_destroy(partners);
727 obstack_free(env->obst, base);
732 * Handle constraint nodes in each basic block.
733 * handle_constraints() inserts Perm nodes which perm
734 * over all values live at the constrained node right in front
735 * of the constrained node. These Perms signal a constrained node.
736 * For further comments, refer to handle_constraints().
738 static void constraints(ir_node *bl, void *data)
740 be_chordal_alloc_env_t *env = data;
743 Start silent in the start block.
744 The silence remains until the first barrier is seen.
745 Each other block is begun loud.
747 int silent = bl == get_irg_start_block(get_irn_irg(bl));
751 If the block is the start block search the barrier and
752 start handling constraints from there.
755 for(irn = sched_first(bl); !sched_is_end(irn);) {
756 irn = handle_constraints(env, irn, &silent);
761 * Annotate the register pressure to the nodes and compute
762 * the liveness intervals.
763 * @param block The block to do it for.
764 * @param env_ptr The environment.
766 static void pressure(ir_node *block, void *env_ptr)
768 /* Convenience macro for a def */
769 #define border_def(irn, step, real) \
770 border_add(env, head, irn, step, pressure--, 1, real)
772 /* Convenience macro for a use */
773 #define border_use(irn, step, real) \
774 border_add(env, head, irn, step, ++pressure, 0, real)
776 be_chordal_alloc_env_t *alloc_env = env_ptr;
777 be_chordal_env_t *env = alloc_env->chordal_env;
778 bitset_t *live = alloc_env->live;
780 be_lv_t *lv = env->birg->lv;
785 unsigned pressure = 0;
786 struct list_head *head;
788 DBG((dbg, LEVEL_1, "Computing pressure in block %+F\n", block));
789 bitset_clear_all(live);
791 /* Set up the border list in the block info */
792 head = obstack_alloc(env->obst, sizeof(*head));
793 INIT_LIST_HEAD(head);
794 assert(pmap_get(env->border_heads, block) == NULL);
795 pmap_insert(env->border_heads, block, head);
798 * Make final uses of all values live out of the block.
799 * They are necessary to build up real intervals.
801 be_lv_foreach(lv, block, be_lv_state_end, i) {
802 ir_node *irn = be_lv_get_irn(lv, block, i);
803 if(has_reg_class(env, irn)) {
804 DBG((dbg, LEVEL_3, "\tMaking live: %+F/%d\n", irn, get_irn_idx(irn)));
805 bitset_set(live, get_irn_idx(irn));
806 border_use(irn, step, 0);
812 * Determine the last uses of a value inside the block, since they are
813 * relevant for the interval borders.
815 sched_foreach_reverse(block, irn) {
816 DBG((dbg, LEVEL_1, "\tinsn: %+F, pressure: %d\n", irn, pressure));
817 DBG((dbg, LEVEL_2, "\tlive: %B\n", live));
819 #ifndef SCHEDULE_PROJS
820 if (get_irn_mode(irn) == mode_T) {
821 const ir_edge_t *edge;
823 foreach_out_edge(irn, edge) {
824 ir_node *proj = get_edge_src_irn(edge);
827 * If the node defines some value, which can put into a
828 * register of the current class, make a border for it.
830 if(has_reg_class(env, proj)) {
831 int nr = get_irn_idx(proj);
833 bitset_clear(live, nr);
834 border_def(proj, step, 1);
840 * If the node defines some value, which can put into a
841 * register of the current class, make a border for it.
843 if(has_reg_class(env, irn)) {
844 int nr = get_irn_idx(irn);
846 bitset_clear(live, nr);
847 border_def(irn, step, 1);
851 * If the node is no phi node we can examine the uses.
854 for(i = 0, n = get_irn_arity(irn); i < n; ++i) {
855 ir_node *op = get_irn_n(irn, i);
857 if(has_reg_class(env, op)) {
858 int nr = get_irn_idx(op);
859 const char *msg = "-";
861 if(!bitset_is_set(live, nr)) {
862 border_use(op, step, 1);
863 bitset_set(live, nr);
867 DBG((dbg, LEVEL_4, "\t\t%s pos: %d, use: %+F\n", msg, i, op));
874 bitset_foreach(live, elm) {
875 ir_node *irn = get_idx_irn(env->irg, elm);
876 if (be_is_live_in(lv, block, irn))
877 border_def(irn, step, 0);
881 static void assign(ir_node *block, void *env_ptr)
883 be_chordal_alloc_env_t *alloc_env = env_ptr;
884 be_chordal_env_t *env = alloc_env->chordal_env;
885 bitset_t *live = alloc_env->live;
886 bitset_t *colors = alloc_env->colors;
887 bitset_t *in_colors = alloc_env->in_colors;
888 const arch_env_t *arch_env = env->birg->main_env->arch_env;
889 struct list_head *head = get_block_border_head(env, block);
890 be_lv_t *lv = env->birg->lv;
891 pset *live_in = be_lv_pset_put_in(lv, block, pset_new_ptr_default());
896 bitset_clear_all(colors);
897 bitset_clear_all(live);
898 bitset_clear_all(in_colors);
900 DBG((dbg, LEVEL_4, "Assigning colors for block %+F\n", block));
901 DBG((dbg, LEVEL_4, "\tusedef chain for block\n"));
902 list_for_each_entry(border_t, b, head, list) {
903 DBG((dbg, LEVEL_4, "\t%s %+F/%d\n", b->is_def ? "def" : "use",
904 b->irn, get_irn_idx(b->irn)));
908 * Add initial defs for all values live in.
909 * Since their colors have already been assigned (The dominators were
910 * allocated before), we have to mark their colors as used also.
912 foreach_pset(live_in, irn) {
913 if(has_reg_class(env, irn)) {
914 const arch_register_t *reg = arch_get_irn_register(arch_env, irn);
917 assert(reg && "Node must have been assigned a register");
918 col = arch_register_get_index(reg);
920 DBG((dbg, LEVEL_4, "%+F has reg %s\n", irn, reg->name));
922 /* Mark the color of the live in value as used. */
923 bitset_set(colors, col);
924 bitset_set(in_colors, col);
926 /* Mark the value live in. */
927 bitset_set(live, get_irn_idx(irn));
932 * Mind that the sequence of defs from back to front defines a perfect
933 * elimination order. So, coloring the definitions from first to last
936 list_for_each_entry_reverse(border_t, b, head, list) {
937 ir_node *irn = b->irn;
938 int nr = get_irn_idx(irn);
939 int ignore = arch_irn_is(arch_env, irn, ignore);
942 * Assign a color, if it is a local def. Global defs already have a
945 if(b->is_def && !be_is_live_in(lv, block, irn)) {
946 const arch_register_t *reg;
949 if(ignore || pset_find_ptr(alloc_env->pre_colored, irn)) {
950 reg = arch_get_irn_register(arch_env, irn);
952 assert(!bitset_is_set(colors, col) && "pre-colored register must be free");
954 col = get_next_free_reg(alloc_env, colors);
955 reg = arch_register_for_index(env->cls, col);
956 assert(arch_get_irn_register(arch_env, irn) == NULL && "This node must not have been assigned a register yet");
957 assert(!arch_register_type_is(reg, ignore) && "Must not assign ignore register");
960 bitset_set(colors, col);
961 arch_set_irn_register(arch_env, irn, reg);
963 DBG((dbg, LEVEL_1, "\tassigning register %s(%d) to %+F\n", arch_register_get_name(reg), col, irn));
965 assert(!bitset_is_set(live, nr) && "Value's definition must not have been encountered");
966 bitset_set(live, nr);
969 /* Clear the color upon a use. */
970 else if(!b->is_def) {
971 const arch_register_t *reg = arch_get_irn_register(arch_env, irn);
974 assert(reg && "Register must have been assigned");
976 col = arch_register_get_index(reg);
978 if(!arch_register_type_is(reg, ignore)) {
979 assert(bitset_is_set(live, nr) && "Cannot have a non live use");
983 bitset_clear(colors, col);
984 bitset_clear(live, nr);
994 static void assign_new(ir_node *block, be_chordal_alloc_env_t *alloc_env, bitset_t *live_end_dom)
996 be_chordal_env_t *env = alloc_env->chordal_env;
997 bitset_t *colors = alloc_env->colors;
998 bitset_t *in_colors = alloc_env->in_colors;
999 bitset_t *live = bitset_irg_malloc(env->irg);
1000 const arch_env_t *arch_env = env->birg->main_env->arch_env;
1001 be_irg_t *birg = env->birg;
1006 bitset_clear_all(colors);
1007 bitset_clear_all(in_colors);
1010 * All variables which are live in to this block are live out
1011 * of the immediate dominator thanks to SSA properties. As we
1012 * have already visited the immediate dominator, we know these
1013 * variables. The only tjing left is to check wheather they are live
1014 * in here (they also could be phi arguments to some ohi not
1015 * in this block, hence we have to check).
1017 bitset_foreach (live_end_dom, elm) {
1018 ir_node *irn = get_idx_irn(env->irg, elm);
1019 if (be_is_live_in(birg->lv, block, irn)) {
1020 const arch_register_t *reg = arch_get_irn_register(arch_env, irn);
1023 assert(be_is_live_in(env->birg->lv, block, irn));
1024 assert(reg && "Node must have been assigned a register");
1025 col = arch_register_get_index(reg);
1027 DBG((dbg, LEVEL_4, "%+F has reg %s\n", irn, reg->name));
1029 /* Mark the color of the live in value as used. */
1030 bitset_set(colors, col);
1031 bitset_set(in_colors, col);
1033 /* Mark the value live in. */
1034 bitset_set(live, elm);
1038 assert(!be_is_live_in(env->birg->lv, block, irn));
1043 * Mind that the sequence of defs from back to front defines a perfect
1044 * elimination order. So, coloring the definitions from first to last
1047 sched_foreach (block, irn) {
1048 int nr = get_irn_idx(irn);
1049 int ignore = arch_irn_is(arch_env, irn, ignore);
1051 /* Clear the color upon a last use. */
1054 for (i = get_irn_arity(irn) - 1; i >= 0; --i) {
1055 ir_node *op = get_irn_n(irn, i);
1058 * If the reg class matches and the operand is not live after
1059 * the node, irn is a last use of op and the register can
1062 if (has_reg_class(env, op)) {
1063 if (!be_lv_chk_after_irn(birg, op, irn)) {
1064 const arch_register_t *reg = arch_get_irn_register(arch_env, op);
1067 assert(reg && "Register must have been assigned");
1068 col = arch_register_get_index(reg);
1069 bitset_clear(colors, col);
1070 bitset_clear(live, nr);
1076 if (has_reg_class(env, irn)) {
1077 const arch_register_t *reg;
1081 * Assign a color, if it is a local def. Global defs already have a
1084 if(ignore || pset_find_ptr(alloc_env->pre_colored, irn)) {
1085 reg = arch_get_irn_register(arch_env, irn);
1087 assert(!bitset_is_set(colors, col) && "pre-colored register must be free");
1089 col = get_next_free_reg(alloc_env, colors);
1090 reg = arch_register_for_index(env->cls, col);
1091 assert(arch_get_irn_register(arch_env, irn) == NULL && "This node must not have been assigned a register yet");
1092 assert(!arch_register_type_is(reg, ignore) && "Must not assign ignore register");
1095 bitset_set(colors, col);
1096 arch_set_irn_register(arch_env, irn, reg);
1098 DBG((dbg, LEVEL_1, "\tassigning register %s(%d) to %+F\n", arch_register_get_name(reg), col, irn));
1100 assert(!bitset_is_set(live, nr) && "Value's definition must not have been encountered");
1101 bitset_set(live, nr);
1106 dominates_for_each (block, irn) {
1107 assign_new(irn, alloc_env, live);
1113 void be_ra_chordal_color(be_chordal_env_t *chordal_env)
1115 be_chordal_alloc_env_t env;
1118 be_irg_t *birg = chordal_env->birg;
1119 const arch_register_class_t *cls = chordal_env->cls;
1121 int colors_n = arch_register_class_n_regs(cls);
1122 ir_graph *irg = chordal_env->irg;
1123 int allocatable_regs = colors_n - be_put_ignore_regs(birg, cls, NULL);
1125 /* some special classes contain only ignore regs, no work to be done */
1126 if(allocatable_regs == 0)
1129 be_assure_dom_front(birg);
1130 lv = be_assure_liveness(birg);
1131 be_liveness_assure_sets(lv);
1132 be_liveness_assure_chk(lv);
1136 env.chordal_env = chordal_env;
1137 env.colors_n = colors_n;
1138 env.colors = bitset_alloca(colors_n);
1139 env.tmp_colors = bitset_alloca(colors_n);
1140 env.in_colors = bitset_alloca(colors_n);
1141 env.pre_colored = pset_new_ptr_default();
1143 /* Handle register targeting constraints */
1144 dom_tree_walk_irg(irg, constraints, NULL, &env);
1146 if(chordal_env->opts->dump_flags & BE_CH_DUMP_CONSTR) {
1147 snprintf(buf, sizeof(buf), "-%s-constr", chordal_env->cls->name);
1148 be_dump(chordal_env->irg, buf, dump_ir_block_graph_sched);
1151 env.live = bitset_malloc(get_irg_last_idx(chordal_env->irg));
1153 /* First, determine the pressure */
1154 dom_tree_walk_irg(irg, pressure, NULL, &env);
1156 /* Assign the colors */
1157 #ifdef NEW_STYLE_ASSIGN
1158 assign_new(get_irg_start_block(irg), &env, env.live);
1160 dom_tree_walk_irg(irg, assign, NULL, &env);
1163 if(chordal_env->opts->dump_flags & BE_CH_DUMP_TREE_INTV) {
1165 ir_snprintf(buf, sizeof(buf), "ifg_%s_%F.eps", chordal_env->cls->name, irg);
1166 plotter = new_plotter_ps(buf);
1167 draw_interval_tree(&draw_chordal_def_opts, chordal_env, plotter);
1168 plotter_free(plotter);
1171 bitset_free(env.live);
1172 del_pset(env.pre_colored);
1175 void be_init_chordal(void)
1177 FIRM_DBG_REGISTER(dbg, "firm.be.chordal");
1180 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_chordal);