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 New approach to allocation and copy coalescing
23 * @author Matthias Braun
27 * ... WE NEED A NAME FOR THIS ...
29 * Only a proof of concept at this moment...
31 * The idea is to allocate registers in 2 passes:
32 * 1. A first pass to determine "preferred" registers for live-ranges. This
33 * calculates for each register and each live-range a value indicating
34 * the usefulness. (You can roughly think of the value as the negative
35 * costs needed for copies when the value is in the specific registers...)
37 * 2. Walk blocks and assigns registers in a greedy fashion. Preferring
38 * registers with high preferences. When register constraints are not met,
39 * add copies and split live-ranges.
42 * - make use of free registers in the permute_values code
43 * - think about a smarter sequence of visiting the blocks. Sorted by
44 * execfreq might be good, or looptree from inner to outermost loops going
45 * over blocks in a reverse postorder
46 * - propagate preferences through Phis
58 #include "iredges_t.h"
59 #include "irgraph_t.h"
64 #include "raw_bitset.h"
65 #include "unionfind.h"
67 #include "hungarian.h"
70 #include "bechordal_t.h"
79 #include "bespillutil.h"
83 #define USE_FACTOR 1.0f
84 #define DEF_FACTOR 1.0f
85 #define NEIGHBOR_FACTOR 0.2f
86 #define AFF_SHOULD_BE_SAME 0.5f
88 #define SPLIT_DELTA 1.0f
90 DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
92 static struct obstack obst;
93 static be_irg_t *birg;
95 static const arch_register_class_t *cls;
96 static const arch_register_req_t *default_cls_req;
98 static const ir_exec_freq *execfreqs;
99 static unsigned n_regs;
100 static unsigned *normal_regs;
101 static int *congruence_classes;
102 static ir_node **block_order;
103 static int n_block_order;
105 /** currently active assignments (while processing a basic block)
106 * maps registers to values(their current copies) */
107 static ir_node **assignments;
110 * allocation information: last_uses, register preferences
111 * the information is per firm-node.
113 struct allocation_info_t {
114 unsigned last_uses; /**< bitset indicating last uses (input pos) */
115 ir_node *current_value; /**< copy of the value that should be used */
116 ir_node *original_value; /**< for copies point to original value */
117 float prefs[0]; /**< register preferences */
119 typedef struct allocation_info_t allocation_info_t;
121 /** helper datastructure used when sorting register preferences */
126 typedef struct reg_pref_t reg_pref_t;
128 /** per basic-block information */
129 struct block_info_t {
130 bool processed; /**< indicate wether block is processed */
131 ir_node *assignments[0]; /**< register assignments at end of block */
133 typedef struct block_info_t block_info_t;
136 * Get the allocation info for a node.
137 * The info is allocated on the first visit of a node.
139 static allocation_info_t *get_allocation_info(ir_node *node)
141 allocation_info_t *info = get_irn_link(node);
143 info = OALLOCFZ(&obst, allocation_info_t, prefs, n_regs);
144 info->current_value = node;
145 info->original_value = node;
146 set_irn_link(node, info);
153 * Get allocation information for a basic block
155 static block_info_t *get_block_info(ir_node *block)
157 block_info_t *info = get_irn_link(block);
159 assert(is_Block(block));
161 info = OALLOCFZ(&obst, block_info_t, assignments, n_regs);
162 set_irn_link(block, info);
169 * Get default register requirement for the current register class
171 static const arch_register_req_t *get_default_req_current_cls(void)
173 if (default_cls_req == NULL) {
174 struct obstack *obst = get_irg_obstack(irg);
175 arch_register_req_t *req = OALLOCZ(obst, arch_register_req_t);
177 req->type = arch_register_req_type_normal;
180 default_cls_req = req;
182 return default_cls_req;
186 * Link the allocation info of a node to a copy.
187 * Afterwards, both nodes uses the same allocation info.
188 * Copy must not have an allocation info assigned yet.
190 * @param copy the node that gets the allocation info assigned
191 * @param value the original node
193 static void mark_as_copy_of(ir_node *copy, ir_node *value)
196 allocation_info_t *info = get_allocation_info(value);
197 allocation_info_t *copy_info = get_allocation_info(copy);
199 /* find original value */
200 original = info->original_value;
201 if (original != value) {
202 info = get_allocation_info(original);
205 assert(info->original_value == original);
206 info->current_value = copy;
208 /* the copy should not be linked to something else yet */
209 assert(copy_info->original_value == copy);
210 copy_info->original_value = original;
212 /* copy over allocation preferences */
213 memcpy(copy_info->prefs, info->prefs, n_regs * sizeof(copy_info->prefs[0]));
217 * Calculate the penalties for every register on a node and its live neighbors.
219 * @param live_nodes the set of live nodes at the current position, may be NULL
220 * @param penalty the penalty to subtract from
221 * @param limited a raw bitset containing the limited set for the node
222 * @param node the node
224 static void give_penalties_for_limits(const ir_nodeset_t *live_nodes,
225 float penalty, const unsigned* limited,
228 ir_nodeset_iterator_t iter;
230 allocation_info_t *info = get_allocation_info(node);
233 /* give penalty for all forbidden regs */
234 for (r = 0; r < n_regs; ++r) {
235 if (rbitset_is_set(limited, r))
238 info->prefs[r] -= penalty;
241 /* all other live values should get a penalty for allowed regs */
242 if (live_nodes == NULL)
245 /* TODO: reduce penalty if there are multiple allowed registers... */
246 penalty *= NEIGHBOR_FACTOR;
247 foreach_ir_nodeset(live_nodes, neighbor, iter) {
248 allocation_info_t *neighbor_info;
250 /* TODO: if op is used on multiple inputs we might not do a
252 if (neighbor == node)
255 neighbor_info = get_allocation_info(neighbor);
256 for (r = 0; r < n_regs; ++r) {
257 if (!rbitset_is_set(limited, r))
260 neighbor_info->prefs[r] -= penalty;
266 * Calculate the preferences of a definition for the current register class.
267 * If the definition uses a limited set of registers, reduce the preferences
268 * for the limited register on the node and its neighbors.
270 * @param live_nodes the set of live nodes at the current node
271 * @param weight the weight
272 * @param node the current node
274 static void check_defs(const ir_nodeset_t *live_nodes, float weight,
277 const arch_register_req_t *req;
279 if (get_irn_mode(node) == mode_T) {
280 const ir_edge_t *edge;
281 foreach_out_edge(node, edge) {
282 ir_node *proj = get_edge_src_irn(edge);
283 check_defs(live_nodes, weight, proj);
288 if (!arch_irn_consider_in_reg_alloc(cls, node))
291 req = arch_get_register_req_out(node);
292 if (req->type & arch_register_req_type_limited) {
293 const unsigned *limited = req->limited;
294 float penalty = weight * DEF_FACTOR;
295 give_penalties_for_limits(live_nodes, penalty, limited, node);
298 if (req->type & arch_register_req_type_should_be_same) {
299 ir_node *insn = skip_Proj(node);
300 allocation_info_t *info = get_allocation_info(node);
301 int arity = get_irn_arity(insn);
304 float factor = 1.0f / rbitset_popcnt(&req->other_same, arity);
305 for (i = 0; i < arity; ++i) {
308 allocation_info_t *op_info;
310 if (!rbitset_is_set(&req->other_same, i))
313 op = get_irn_n(insn, i);
315 /* if we the value at the should_be_same input doesn't die at the
316 * node, then it is no use to propagate the constraints (since a
317 * copy will emerge anyway) */
318 if (ir_nodeset_contains(live_nodes, op))
321 op_info = get_allocation_info(op);
322 for (r = 0; r < n_regs; ++r) {
323 op_info->prefs[r] += info->prefs[r] * factor;
330 * Walker: Runs an a block calculates the preferences for any
331 * node and every register from the considered register class.
333 static void analyze_block(ir_node *block, void *data)
335 float weight = get_block_execfreq(execfreqs, block);
336 ir_nodeset_t live_nodes;
340 ir_nodeset_init(&live_nodes);
341 be_liveness_end_of_block(lv, cls, block, &live_nodes);
343 sched_foreach_reverse(block, node) {
344 allocation_info_t *info;
351 check_defs(&live_nodes, weight, node);
354 arity = get_irn_arity(node);
356 /* the allocation info node currently only uses 1 unsigned value
357 to mark last used inputs. So we will fail for a node with more than
359 if (arity >= (int) sizeof(unsigned) * 8) {
360 panic("Node with more than %d inputs not supported yet",
361 (int) sizeof(unsigned) * 8);
364 info = get_allocation_info(node);
365 for (i = 0; i < arity; ++i) {
366 ir_node *op = get_irn_n(node, i);
367 if (!arch_irn_consider_in_reg_alloc(cls, op))
370 /* last usage of a value? */
371 if (!ir_nodeset_contains(&live_nodes, op)) {
372 rbitset_set(&info->last_uses, i);
376 be_liveness_transfer(cls, node, &live_nodes);
378 /* update weights based on usage constraints */
379 for (i = 0; i < arity; ++i) {
380 const arch_register_req_t *req;
381 const unsigned *limited;
382 ir_node *op = get_irn_n(node, i);
384 if (!arch_irn_consider_in_reg_alloc(cls, op))
387 req = arch_get_register_req(node, i);
388 if (!(req->type & arch_register_req_type_limited))
391 limited = req->limited;
392 give_penalties_for_limits(&live_nodes, weight * USE_FACTOR, limited,
397 ir_nodeset_destroy(&live_nodes);
400 static void congruence_def(ir_nodeset_t *live_nodes, ir_node *node)
402 const arch_register_req_t *req;
404 if (get_irn_mode(node) == mode_T) {
405 const ir_edge_t *edge;
406 foreach_out_edge(node, edge) {
407 ir_node *def = get_edge_src_irn(edge);
408 congruence_def(live_nodes, def);
413 if (!arch_irn_consider_in_reg_alloc(cls, node))
416 /* should be same constraint? */
417 req = arch_get_register_req_out(node);
418 if (req->type & arch_register_req_type_should_be_same) {
419 ir_node *insn = skip_Proj(node);
420 int arity = get_irn_arity(insn);
422 unsigned node_idx = get_irn_idx(node);
423 node_idx = uf_find(congruence_classes, node_idx);
425 for (i = 0; i < arity; ++i) {
429 ir_nodeset_iterator_t iter;
430 bool interferes = false;
432 if (!rbitset_is_set(&req->other_same, i))
435 op = get_irn_n(insn, i);
436 op_idx = get_irn_idx(op);
437 op_idx = uf_find(congruence_classes, op_idx);
439 /* do we interfere with the value */
440 foreach_ir_nodeset(live_nodes, live, iter) {
441 int lv_idx = get_irn_idx(live);
442 lv_idx = uf_find(congruence_classes, lv_idx);
443 if (lv_idx == op_idx) {
448 /* don't put in same affinity class if we interfere */
452 node_idx = uf_union(congruence_classes, node_idx, op_idx);
453 DB((dbg, LEVEL_3, "Merge %+F and %+F congruence classes\n",
455 /* one should_be_same is enough... */
461 static void create_congurence_class(ir_node *block, void *data)
463 ir_nodeset_t live_nodes;
467 ir_nodeset_init(&live_nodes);
468 be_liveness_end_of_block(lv, cls, block, &live_nodes);
470 /* check should be same constraints */
471 sched_foreach_reverse(block, node) {
475 congruence_def(&live_nodes, node);
476 be_liveness_transfer(cls, node, &live_nodes);
479 /* check phi congruence classes */
480 sched_foreach_reverse_from(node, node) {
484 assert(is_Phi(node));
486 if (!arch_irn_consider_in_reg_alloc(cls, node))
489 node_idx = get_irn_idx(node);
490 node_idx = uf_find(congruence_classes, node_idx);
492 arity = get_irn_arity(node);
493 for (i = 0; i < arity; ++i) {
494 bool interferes = false;
495 ir_nodeset_iterator_t iter;
498 ir_node *op = get_Phi_pred(node, i);
499 int op_idx = get_irn_idx(op);
500 op_idx = uf_find(congruence_classes, op_idx);
502 /* do we interfere with the value */
503 foreach_ir_nodeset(&live_nodes, live, iter) {
504 int lv_idx = get_irn_idx(live);
505 lv_idx = uf_find(congruence_classes, lv_idx);
506 if (lv_idx == op_idx) {
511 /* don't put in same affinity class if we interfere */
514 /* any other phi has the same input? */
515 sched_foreach(block, phi) {
520 if (!arch_irn_consider_in_reg_alloc(cls, phi))
522 oop = get_Phi_pred(phi, i);
525 oop_idx = get_irn_idx(oop);
526 oop_idx = uf_find(congruence_classes, oop_idx);
527 if (oop_idx == op_idx) {
535 node_idx = uf_union(congruence_classes, node_idx, op_idx);
536 DB((dbg, LEVEL_3, "Merge %+F and %+F congruence classes\n",
542 static void merge_congruence_prefs(ir_node *node, void *data)
544 allocation_info_t *info;
545 allocation_info_t *head_info;
546 unsigned node_idx = get_irn_idx(node);
547 unsigned node_set = uf_find(congruence_classes, node_idx);
552 /* head of congruence class or not in any class */
553 if (node_set == node_idx)
556 if (!arch_irn_consider_in_reg_alloc(cls, node))
559 head_info = get_allocation_info(get_idx_irn(irg, node_set));
560 info = get_allocation_info(node);
562 for (r = 0; r < n_regs; ++r) {
563 head_info->prefs[r] += info->prefs[r];
567 static void set_congruence_prefs(ir_node *node, void *data)
569 allocation_info_t *info;
570 allocation_info_t *head_info;
571 unsigned node_idx = get_irn_idx(node);
572 unsigned node_set = uf_find(congruence_classes, node_idx);
576 /* head of congruence class or not in any class */
577 if (node_set == node_idx)
580 if (!arch_irn_consider_in_reg_alloc(cls, node))
583 head_info = get_allocation_info(get_idx_irn(irg, node_set));
584 info = get_allocation_info(node);
586 memcpy(info->prefs, head_info->prefs, n_regs * sizeof(info->prefs[0]));
589 static void combine_congruence_classes(void)
591 size_t n = get_irg_last_idx(irg);
592 congruence_classes = XMALLOCN(int, n);
593 uf_init(congruence_classes, n);
595 /* create congruence classes */
596 irg_block_walk_graph(irg, create_congurence_class, NULL, NULL);
597 /* merge preferences */
598 irg_walk_graph(irg, merge_congruence_prefs, NULL, NULL);
599 irg_walk_graph(irg, set_congruence_prefs, NULL, NULL);
607 * Assign register reg to the given node.
609 * @param node the node
610 * @param reg the register
612 static void use_reg(ir_node *node, const arch_register_t *reg)
614 unsigned r = arch_register_get_index(reg);
615 assignments[r] = node;
616 arch_set_irn_register(node, reg);
619 static void free_reg_of_value(ir_node *node)
621 const arch_register_t *reg;
624 if (!arch_irn_consider_in_reg_alloc(cls, node))
627 reg = arch_get_irn_register(node);
628 r = arch_register_get_index(reg);
629 /* assignment->value may be NULL if a value is used at 2 inputs
630 so it gets freed twice. */
631 assert(assignments[r] == node || assignments[r] == NULL);
632 assignments[r] = NULL;
636 * Compare two register preferences in decreasing order.
638 static int compare_reg_pref(const void *e1, const void *e2)
640 const reg_pref_t *rp1 = (const reg_pref_t*) e1;
641 const reg_pref_t *rp2 = (const reg_pref_t*) e2;
642 if (rp1->pref < rp2->pref)
644 if (rp1->pref > rp2->pref)
649 static void fill_sort_candidates(reg_pref_t *regprefs,
650 const allocation_info_t *info)
654 for (r = 0; r < n_regs; ++r) {
655 float pref = info->prefs[r];
657 regprefs[r].pref = pref;
659 /* TODO: use a stable sort here to avoid unnecessary register jumping */
660 qsort(regprefs, n_regs, sizeof(regprefs[0]), compare_reg_pref);
663 static bool try_optimistic_split(ir_node *to_split, ir_node *before,
664 float pref, float pref_delta,
665 unsigned *output_regs)
667 const arch_register_t *reg;
668 ir_node *original_insn;
673 allocation_info_t *info = get_allocation_info(to_split);
676 float split_threshold;
680 /* stupid hack: don't optimisticallt split don't spill nodes...
681 * (so we don't split away the values produced because of
682 * must_be_different constraints) */
683 original_insn = skip_Proj(info->original_value);
684 if (arch_irn_get_flags(original_insn) & arch_irn_flags_dont_spill)
687 /* find the best free position where we could move to */
688 prefs = ALLOCAN(reg_pref_t, n_regs);
689 fill_sort_candidates(prefs, info);
690 for (i = 0; i < n_regs; ++i) {
692 if (!rbitset_is_set(normal_regs, r))
694 if (rbitset_is_set(output_regs, r))
696 if (assignments[r] == NULL)
702 /* TODO: use execfreq somehow... */
703 block = get_nodes_block(before);
704 delta = pref_delta + prefs[i].pref;
705 split_threshold = get_block_execfreq(execfreqs, block) * SPLIT_DELTA;
706 if (delta < split_threshold) {
707 DB((dbg, LEVEL_3, "Not doing optimistical split, win %f too low\n",
712 reg = arch_register_for_index(cls, r);
713 copy = be_new_Copy(cls, block, to_split);
714 mark_as_copy_of(copy, to_split);
715 free_reg_of_value(to_split);
717 sched_add_before(before, copy);
720 "Optimistic live-range split %+F move %+F -> %s before %+F (win %f)\n",
721 copy, to_split, reg->name, before, delta));
726 * Determine and assign a register for node @p node
728 static void assign_reg(const ir_node *block, ir_node *node,
729 unsigned *output_regs)
731 const arch_register_t *reg;
732 allocation_info_t *info;
733 const arch_register_req_t *req;
734 reg_pref_t *reg_prefs;
737 const unsigned *allowed_regs;
740 assert(arch_irn_consider_in_reg_alloc(cls, node));
742 /* preassigned register? */
743 reg = arch_get_irn_register(node);
745 DB((dbg, LEVEL_2, "Preassignment %+F -> %s\n", node, reg->name));
750 /* give should_be_same boni */
751 info = get_allocation_info(node);
752 req = arch_get_register_req_out(node);
754 in_node = skip_Proj(node);
755 if (req->type & arch_register_req_type_should_be_same) {
756 float weight = get_block_execfreq(execfreqs, block);
757 int arity = get_irn_arity(in_node);
760 assert(arity <= (int) sizeof(req->other_same) * 8);
761 for (i = 0; i < arity; ++i) {
763 const arch_register_t *reg;
765 if (!rbitset_is_set(&req->other_same, i))
768 in = get_irn_n(in_node, i);
769 reg = arch_get_irn_register(in);
771 r = arch_register_get_index(reg);
773 /* if the value didn't die here then we should not propagate the
774 * should_be_same info */
775 if (assignments[r] == in)
778 info->prefs[r] += weight * AFF_SHOULD_BE_SAME;
782 /* create list of register candidates and sort by their preference */
783 DB((dbg, LEVEL_2, "Candidates for %+F:", node));
784 reg_prefs = alloca(n_regs * sizeof(reg_prefs[0]));
785 fill_sort_candidates(reg_prefs, info);
786 for (i = 0; i < n_regs; ++i) {
787 unsigned num = reg_prefs[i].num;
788 const arch_register_t *reg;
790 if (!rbitset_is_set(normal_regs, num))
793 reg = arch_register_for_index(cls, num);
794 DB((dbg, LEVEL_2, " %s(%f)", reg->name, reg_prefs[i].pref));
796 DB((dbg, LEVEL_2, "\n"));
798 allowed_regs = normal_regs;
799 if (req->type & arch_register_req_type_limited) {
800 allowed_regs = req->limited;
803 for (i = 0; i < n_regs; ++i) {
804 r = reg_prefs[i].num;
805 if (!rbitset_is_set(allowed_regs, r))
807 if (assignments[r] == NULL)
810 float pref = reg_prefs[i].pref;
811 float delta = i+1 < n_regs ? pref - reg_prefs[i+1].pref : 0;
812 ir_node *before = skip_Proj(node);
813 bool res = try_optimistic_split(assignments[r], before,
821 panic("No register left for %+F\n", node);
824 reg = arch_register_for_index(cls, r);
825 DB((dbg, LEVEL_2, "Assign %+F -> %s\n", node, reg->name));
830 * Add an permutation in front of a node and change the assignments
831 * due to this permutation.
833 * To understand this imagine a permutation like this:
843 * First we count how many destinations a single value has. At the same time
844 * we can be sure that each destination register has at most 1 source register
845 * (it can have 0 which means we don't care what value is in it).
846 * We ignore all fullfilled permuations (like 7->7)
847 * In a first pass we create as much copy instructions as possible as they
848 * are generally cheaper than exchanges. We do this by counting into how many
849 * destinations a register has to be copied (in the example it's 2 for register
850 * 3, or 1 for the registers 1,2,4 and 7).
851 * We can then create a copy into every destination register when the usecount
852 * of that register is 0 (= noone else needs the value in the register).
854 * After this step we should have cycles left. We implement a cyclic permutation
855 * of n registers with n-1 transpositions.
857 * @param live_nodes the set of live nodes, updated due to live range split
858 * @param before the node before we add the permutation
859 * @param permutation the permutation array indices are the destination
860 * registers, the values in the array are the source
863 static void permute_values(ir_nodeset_t *live_nodes, ir_node *before,
864 unsigned *permutation)
866 unsigned *n_used = ALLOCANZ(unsigned, n_regs);
870 /* determine how often each source register needs to be read */
871 for (r = 0; r < n_regs; ++r) {
872 unsigned old_reg = permutation[r];
875 value = assignments[old_reg];
877 /* nothing to do here, reg is not live. Mark it as fixpoint
878 * so we ignore it in the next steps */
886 block = get_nodes_block(before);
888 /* step1: create copies where immediately possible */
889 for (r = 0; r < n_regs; /* empty */) {
892 const arch_register_t *reg;
893 unsigned old_r = permutation[r];
895 /* - no need to do anything for fixed points.
896 - we can't copy if the value in the dest reg is still needed */
897 if (old_r == r || n_used[r] > 0) {
903 src = assignments[old_r];
904 copy = be_new_Copy(cls, block, src);
905 sched_add_before(before, copy);
906 reg = arch_register_for_index(cls, r);
907 DB((dbg, LEVEL_2, "Copy %+F (from %+F, before %+F) -> %s\n",
908 copy, src, before, reg->name));
909 mark_as_copy_of(copy, src);
912 if (live_nodes != NULL) {
913 ir_nodeset_insert(live_nodes, copy);
916 /* old register has 1 user less, permutation is resolved */
917 assert(arch_register_get_index(arch_get_irn_register(src)) == old_r);
920 assert(n_used[old_r] > 0);
922 if (n_used[old_r] == 0) {
923 if (live_nodes != NULL) {
924 ir_nodeset_remove(live_nodes, src);
926 free_reg_of_value(src);
929 /* advance or jump back (if this copy enabled another copy) */
930 if (old_r < r && n_used[old_r] == 0) {
937 /* at this point we only have "cycles" left which we have to resolve with
939 * TODO: if we have free registers left, then we should really use copy
940 * instructions for any cycle longer than 2 registers...
941 * (this is probably architecture dependent, there might be archs where
942 * copies are preferable even for 2-cycles) */
944 /* create perms with the rest */
945 for (r = 0; r < n_regs; /* empty */) {
946 const arch_register_t *reg;
947 unsigned old_r = permutation[r];
959 /* we shouldn't have copies from 1 value to multiple destinations left*/
960 assert(n_used[old_r] == 1);
962 /* exchange old_r and r2; after that old_r is a fixed point */
963 r2 = permutation[old_r];
965 in[0] = assignments[r2];
966 in[1] = assignments[old_r];
967 perm = be_new_Perm(cls, block, 2, in);
968 sched_add_before(before, perm);
969 DB((dbg, LEVEL_2, "Perm %+F (perm %+F,%+F, before %+F)\n",
970 perm, in[0], in[1], before));
972 proj0 = new_r_Proj(block, perm, get_irn_mode(in[0]), 0);
973 mark_as_copy_of(proj0, in[0]);
974 reg = arch_register_for_index(cls, old_r);
977 proj1 = new_r_Proj(block, perm, get_irn_mode(in[1]), 1);
978 mark_as_copy_of(proj1, in[1]);
979 reg = arch_register_for_index(cls, r2);
982 /* 1 value is now in the correct register */
983 permutation[old_r] = old_r;
984 /* the source of r changed to r2 */
987 /* if we have reached a fixpoint update data structures */
988 if (live_nodes != NULL) {
989 ir_nodeset_remove(live_nodes, in[0]);
990 ir_nodeset_remove(live_nodes, in[1]);
991 ir_nodeset_remove(live_nodes, proj0);
992 ir_nodeset_insert(live_nodes, proj1);
997 /* now we should only have fixpoints left */
998 for (r = 0; r < n_regs; ++r) {
999 assert(permutation[r] == r);
1005 * Free regs for values last used.
1007 * @param live_nodes set of live nodes, will be updated
1008 * @param node the node to consider
1010 static void free_last_uses(ir_nodeset_t *live_nodes, ir_node *node)
1012 allocation_info_t *info = get_allocation_info(node);
1013 const unsigned *last_uses = &info->last_uses;
1014 int arity = get_irn_arity(node);
1017 for (i = 0; i < arity; ++i) {
1020 /* check if one operand is the last use */
1021 if (!rbitset_is_set(last_uses, i))
1024 op = get_irn_n(node, i);
1025 free_reg_of_value(op);
1026 ir_nodeset_remove(live_nodes, op);
1031 * change inputs of a node to the current value (copies/perms)
1033 static void rewire_inputs(ir_node *node)
1036 int arity = get_irn_arity(node);
1038 for (i = 0; i < arity; ++i) {
1039 ir_node *op = get_irn_n(node, i);
1040 allocation_info_t *info;
1042 if (!arch_irn_consider_in_reg_alloc(cls, op))
1045 info = get_allocation_info(op);
1046 info = get_allocation_info(info->original_value);
1047 if (info->current_value != op) {
1048 set_irn_n(node, i, info->current_value);
1054 * Create a bitset of registers occupied with value living through an
1057 static void determine_live_through_regs(unsigned *bitset, ir_node *node)
1059 const allocation_info_t *info = get_allocation_info(node);
1064 /* mark all used registers as potentially live-through */
1065 for (r = 0; r < n_regs; ++r) {
1066 if (assignments[r] == NULL)
1068 if (!rbitset_is_set(normal_regs, r))
1071 rbitset_set(bitset, r);
1074 /* remove registers of value dying at the instruction */
1075 arity = get_irn_arity(node);
1076 for (i = 0; i < arity; ++i) {
1078 const arch_register_t *reg;
1080 if (!rbitset_is_set(&info->last_uses, i))
1083 op = get_irn_n(node, i);
1084 reg = arch_get_irn_register(op);
1085 rbitset_clear(bitset, arch_register_get_index(reg));
1090 * Enforce constraints at a node by live range splits.
1092 * @param live_nodes the set of live nodes, might be changed
1093 * @param node the current node
1095 static void enforce_constraints(ir_nodeset_t *live_nodes, ir_node *node,
1096 unsigned *output_regs)
1098 int arity = get_irn_arity(node);
1100 hungarian_problem_t *bp;
1102 unsigned *assignment;
1104 /* construct a list of register occupied by live-through values */
1105 unsigned *live_through_regs = NULL;
1107 /* see if any use constraints are not met */
1109 for (i = 0; i < arity; ++i) {
1110 ir_node *op = get_irn_n(node, i);
1111 const arch_register_t *reg;
1112 const arch_register_req_t *req;
1113 const unsigned *limited;
1116 if (!arch_irn_consider_in_reg_alloc(cls, op))
1119 /* are there any limitations for the i'th operand? */
1120 req = arch_get_register_req(node, i);
1121 if (!(req->type & arch_register_req_type_limited))
1124 limited = req->limited;
1125 reg = arch_get_irn_register(op);
1126 r = arch_register_get_index(reg);
1127 if (!rbitset_is_set(limited, r)) {
1128 /* found an assignment outside the limited set */
1134 /* is any of the live-throughs using a constrained output register? */
1135 if (get_irn_mode(node) == mode_T) {
1136 const ir_edge_t *edge;
1138 foreach_out_edge(node, edge) {
1139 ir_node *proj = get_edge_src_irn(edge);
1140 const arch_register_req_t *req;
1142 if (!arch_irn_consider_in_reg_alloc(cls, proj))
1145 req = arch_get_register_req_out(proj);
1146 if (!(req->type & arch_register_req_type_limited))
1149 if (live_through_regs == NULL) {
1150 rbitset_alloca(live_through_regs, n_regs);
1151 determine_live_through_regs(live_through_regs, node);
1154 rbitset_or(output_regs, req->limited, n_regs);
1155 if (rbitsets_have_common(req->limited, live_through_regs, n_regs)) {
1160 if (arch_irn_consider_in_reg_alloc(cls, node)) {
1161 const arch_register_req_t *req = arch_get_register_req_out(node);
1162 if (req->type & arch_register_req_type_limited) {
1163 rbitset_alloca(live_through_regs, n_regs);
1164 determine_live_through_regs(live_through_regs, node);
1165 if (rbitsets_have_common(req->limited, live_through_regs, n_regs)) {
1167 rbitset_or(output_regs, req->limited, n_regs);
1176 /* create these arrays if we haven't yet */
1177 if (live_through_regs == NULL) {
1178 rbitset_alloca(live_through_regs, n_regs);
1181 /* at this point we have to construct a bipartite matching problem to see
1182 * which values should go to which registers
1183 * Note: We're building the matrix in "reverse" - source registers are
1184 * right, destinations left because this will produce the solution
1185 * in the format required for permute_values.
1187 bp = hungarian_new(n_regs, n_regs, HUNGARIAN_MATCH_PERFECT);
1189 /* add all combinations, then remove not allowed ones */
1190 for (l = 0; l < n_regs; ++l) {
1191 if (!rbitset_is_set(normal_regs, l)) {
1192 hungarian_add(bp, l, l, 1);
1196 for (r = 0; r < n_regs; ++r) {
1197 if (!rbitset_is_set(normal_regs, r))
1199 /* livethrough values may not use constrainted output registers */
1200 if (rbitset_is_set(live_through_regs, l)
1201 && rbitset_is_set(output_regs, r))
1204 hungarian_add(bp, r, l, l == r ? 9 : 8);
1208 for (i = 0; i < arity; ++i) {
1209 ir_node *op = get_irn_n(node, i);
1210 const arch_register_t *reg;
1211 const arch_register_req_t *req;
1212 const unsigned *limited;
1213 unsigned current_reg;
1215 if (!arch_irn_consider_in_reg_alloc(cls, op))
1218 req = arch_get_register_req(node, i);
1219 if (!(req->type & arch_register_req_type_limited))
1222 limited = req->limited;
1223 reg = arch_get_irn_register(op);
1224 current_reg = arch_register_get_index(reg);
1225 for (r = 0; r < n_regs; ++r) {
1226 if (rbitset_is_set(limited, r))
1228 hungarian_remv(bp, r, current_reg);
1232 //hungarian_print_cost_matrix(bp, 1);
1233 hungarian_prepare_cost_matrix(bp, HUNGARIAN_MODE_MAXIMIZE_UTIL);
1235 assignment = ALLOCAN(unsigned, n_regs);
1236 res = hungarian_solve(bp, (int*) assignment, NULL, 0);
1240 fprintf(stderr, "Swap result:");
1241 for (i = 0; i < (int) n_regs; ++i) {
1242 fprintf(stderr, " %d", assignment[i]);
1244 fprintf(stderr, "\n");
1249 permute_values(live_nodes, node, assignment);
1252 /** test wether a node @p n is a copy of the value of node @p of */
1253 static bool is_copy_of(ir_node *value, ir_node *test_value)
1255 allocation_info_t *test_info;
1256 allocation_info_t *info;
1258 if (value == test_value)
1261 info = get_allocation_info(value);
1262 test_info = get_allocation_info(test_value);
1263 return test_info->original_value == info->original_value;
1267 * find a value in the end-assignment of a basic block
1268 * @returns the index into the assignment array if found
1271 static int find_value_in_block_info(block_info_t *info, ir_node *value)
1274 ir_node **assignments = info->assignments;
1275 for (r = 0; r < n_regs; ++r) {
1276 ir_node *a_value = assignments[r];
1278 if (a_value == NULL)
1280 if (is_copy_of(a_value, value))
1288 * Create the necessary permutations at the end of a basic block to fullfill
1289 * the register assignment for phi-nodes in the next block
1291 static void add_phi_permutations(ir_node *block, int p)
1294 unsigned *permutation;
1295 ir_node **old_assignments;
1296 bool need_permutation;
1298 ir_node *pred = get_Block_cfgpred_block(block, p);
1300 block_info_t *pred_info = get_block_info(pred);
1302 /* predecessor not processed yet? nothing to do */
1303 if (!pred_info->processed)
1306 permutation = ALLOCAN(unsigned, n_regs);
1307 for (r = 0; r < n_regs; ++r) {
1311 /* check phi nodes */
1312 need_permutation = false;
1313 node = sched_first(block);
1314 for ( ; is_Phi(node); node = sched_next(node)) {
1315 const arch_register_t *reg;
1320 if (!arch_irn_consider_in_reg_alloc(cls, node))
1323 op = get_Phi_pred(node, p);
1324 if (!arch_irn_consider_in_reg_alloc(cls, op))
1327 a = find_value_in_block_info(pred_info, op);
1330 reg = arch_get_irn_register(node);
1331 regn = arch_register_get_index(reg);
1333 permutation[regn] = a;
1334 need_permutation = true;
1338 if (need_permutation) {
1339 /* permute values at end of predecessor */
1340 old_assignments = assignments;
1341 assignments = pred_info->assignments;
1342 permute_values(NULL, be_get_end_of_block_insertion_point(pred),
1344 assignments = old_assignments;
1347 /* change phi nodes to use the copied values */
1348 node = sched_first(block);
1349 for ( ; is_Phi(node); node = sched_next(node)) {
1353 if (!arch_irn_consider_in_reg_alloc(cls, node))
1356 op = get_Phi_pred(node, p);
1357 /* no need to do anything for Unknown inputs */
1358 if (!arch_irn_consider_in_reg_alloc(cls, op))
1361 /* we have permuted all values into the correct registers so we can
1362 simply query which value occupies the phis register in the
1364 a = arch_register_get_index(arch_get_irn_register(node));
1365 op = pred_info->assignments[a];
1366 set_Phi_pred(node, p, op);
1371 * Set preferences for a phis register based on the registers used on the
1374 static void adapt_phi_prefs(ir_node *phi)
1377 int arity = get_irn_arity(phi);
1378 ir_node *block = get_nodes_block(phi);
1379 allocation_info_t *info = get_allocation_info(phi);
1381 for (i = 0; i < arity; ++i) {
1382 ir_node *op = get_irn_n(phi, i);
1383 const arch_register_t *reg = arch_get_irn_register(op);
1384 ir_node *pred_block;
1385 block_info_t *pred_block_info;
1391 /* we only give the bonus if the predecessor already has registers
1392 * assigned, otherwise we only see a dummy value
1393 * and any conclusions about its register are useless */
1394 pred_block = get_Block_cfgpred_block(block, i);
1395 pred_block_info = get_block_info(pred_block);
1396 if (!pred_block_info->processed)
1399 /* give bonus for already assigned register */
1400 weight = get_block_execfreq(execfreqs, pred_block);
1401 r = arch_register_get_index(reg);
1402 info->prefs[r] += weight * AFF_PHI;
1407 * After a phi has been assigned a register propagate preference inputs
1408 * to the phi inputs.
1410 static void propagate_phi_register(ir_node *phi, unsigned r)
1413 ir_node *block = get_nodes_block(phi);
1414 int arity = get_irn_arity(phi);
1416 for (i = 0; i < arity; ++i) {
1417 ir_node *op = get_Phi_pred(phi, i);
1418 allocation_info_t *info = get_allocation_info(op);
1419 ir_node *pred_block = get_Block_cfgpred_block(block, i);
1421 = get_block_execfreq(execfreqs, pred_block) * AFF_PHI;
1423 if (info->prefs[r] >= weight)
1426 /* promote the prefered register */
1427 info->prefs[r] = AFF_PHI * weight;
1429 propagate_phi_register(op, r);
1433 static void assign_phi_registers(ir_node *block)
1440 hungarian_problem_t *bp;
1442 /* count phi nodes */
1443 sched_foreach(block, node) {
1446 if (!arch_irn_consider_in_reg_alloc(cls, node))
1454 /* build a bipartite matching problem for all phi nodes */
1455 bp = hungarian_new(n_phis, n_regs, HUNGARIAN_MATCH_PERFECT);
1457 sched_foreach(block, node) {
1460 allocation_info_t *info;
1463 if (!arch_irn_consider_in_reg_alloc(cls, node))
1466 /* give boni for predecessor colorings */
1467 adapt_phi_prefs(node);
1468 /* add stuff to bipartite problem */
1469 info = get_allocation_info(node);
1470 DB((dbg, LEVEL_3, "Prefs for %+F: ", node));
1471 for (r = 0; r < n_regs; ++r) {
1474 if (!rbitset_is_set(normal_regs, r))
1477 costs = info->prefs[r];
1478 costs = costs < 0 ? -logf(-costs+1) : logf(costs+1);
1481 hungarian_add(bp, n, r, costs);
1482 DB((dbg, LEVEL_3, " %s(%f)", arch_register_for_index(cls, r)->name,
1485 DB((dbg, LEVEL_3, "\n"));
1489 //hungarian_print_cost_matrix(bp, 7);
1490 hungarian_prepare_cost_matrix(bp, HUNGARIAN_MODE_MAXIMIZE_UTIL);
1492 assignment = ALLOCAN(int, n_regs);
1493 res = hungarian_solve(bp, assignment, NULL, 0);
1498 sched_foreach(block, node) {
1500 const arch_register_t *reg;
1504 if (!arch_irn_consider_in_reg_alloc(cls, node))
1507 r = assignment[n++];
1508 assert(rbitset_is_set(normal_regs, r));
1509 reg = arch_register_for_index(cls, r);
1510 DB((dbg, LEVEL_2, "Assign %+F -> %s\n", node, reg->name));
1513 /* adapt preferences for phi inputs */
1514 propagate_phi_register(node, r);
1519 * Walker: assign registers to all nodes of a block that
1520 * need registers from the currently considered register class.
1522 static void allocate_coalesce_block(ir_node *block, void *data)
1525 ir_nodeset_t live_nodes;
1526 ir_nodeset_iterator_t iter;
1529 block_info_t *block_info;
1530 block_info_t **pred_block_infos;
1532 unsigned *output_regs; /**< collects registers which must not
1533 be used for optimistic splits */
1536 DB((dbg, LEVEL_2, "* Block %+F\n", block));
1538 /* clear assignments */
1539 block_info = get_block_info(block);
1540 assignments = block_info->assignments;
1542 ir_nodeset_init(&live_nodes);
1544 /* gather regalloc infos of predecessor blocks */
1545 n_preds = get_Block_n_cfgpreds(block);
1546 pred_block_infos = ALLOCAN(block_info_t*, n_preds);
1547 for (i = 0; i < n_preds; ++i) {
1548 ir_node *pred = get_Block_cfgpred_block(block, i);
1549 block_info_t *pred_info = get_block_info(pred);
1550 pred_block_infos[i] = pred_info;
1553 phi_ins = ALLOCAN(ir_node*, n_preds);
1555 /* collect live-in nodes and preassigned values */
1556 be_lv_foreach(lv, block, be_lv_state_in, i) {
1557 const arch_register_t *reg;
1559 bool need_phi = false;
1561 node = be_lv_get_irn(lv, block, i);
1562 if (!arch_irn_consider_in_reg_alloc(cls, node))
1565 /* check all predecessors for this value, if it is not everywhere the
1566 same or unknown then we have to construct a phi
1567 (we collect the potential phi inputs here) */
1568 for (p = 0; p < n_preds; ++p) {
1569 block_info_t *pred_info = pred_block_infos[p];
1571 if (!pred_info->processed) {
1572 /* use node for now, it will get fixed later */
1576 int a = find_value_in_block_info(pred_info, node);
1578 /* must live out of predecessor */
1580 phi_ins[p] = pred_info->assignments[a];
1581 /* different value from last time? then we need a phi */
1582 if (p > 0 && phi_ins[p-1] != phi_ins[p]) {
1589 ir_mode *mode = get_irn_mode(node);
1590 const arch_register_req_t *req = get_default_req_current_cls();
1594 phi = new_r_Phi(block, n_preds, phi_ins, mode);
1595 be_set_phi_reg_req(phi, req);
1597 DB((dbg, LEVEL_3, "Create Phi %+F (for %+F) -", phi, node));
1598 #ifdef DEBUG_libfirm
1599 for (i = 0; i < n_preds; ++i) {
1600 DB((dbg, LEVEL_3, " %+F", phi_ins[i]));
1602 DB((dbg, LEVEL_3, "\n"));
1604 mark_as_copy_of(phi, node);
1605 sched_add_after(block, phi);
1609 allocation_info_t *info = get_allocation_info(node);
1610 info->current_value = phi_ins[0];
1612 /* Grab 1 of the inputs we constructed (might not be the same as
1613 * "node" as we could see the same copy of the value in all
1618 /* if the node already has a register assigned use it */
1619 reg = arch_get_irn_register(node);
1621 /* TODO: consult pred-block infos here. The value could be copied
1622 away in some/all predecessor blocks. We need to construct
1623 phi-nodes in this case.
1624 We even need to construct some Phi_0 like constructs in cases
1625 where the predecessor allocation is not determined yet. */
1629 /* remember that this node is live at the beginning of the block */
1630 ir_nodeset_insert(&live_nodes, node);
1633 rbitset_alloca(output_regs, n_regs);
1635 /* handle phis... */
1636 assign_phi_registers(block);
1638 /* assign regs for live-in values */
1639 foreach_ir_nodeset(&live_nodes, node, iter) {
1640 const arch_register_t *reg = arch_get_irn_register(node);
1644 assign_reg(block, node, output_regs);
1645 /* shouldn't happen if we color in dominance order */
1646 assert (!is_Phi(node));
1649 /* assign instructions in the block */
1650 sched_foreach(block, node) {
1653 /* phis are already assigned */
1657 rewire_inputs(node);
1659 /* enforce use constraints */
1660 rbitset_clear_all(output_regs, n_regs);
1661 enforce_constraints(&live_nodes, node, output_regs);
1662 /* we may not use registers occupied here for optimistic splits */
1663 for (r = 0; r < n_regs; ++r) {
1664 if (assignments[r] != NULL)
1665 rbitset_set(output_regs, r);
1668 rewire_inputs(node);
1670 /* free registers of values last used at this instruction */
1671 free_last_uses(&live_nodes, node);
1673 /* assign output registers */
1674 /* TODO: 2 phases: first: pre-assigned ones, 2nd real regs */
1675 if (get_irn_mode(node) == mode_T) {
1676 const ir_edge_t *edge;
1677 foreach_out_edge(node, edge) {
1678 ir_node *proj = get_edge_src_irn(edge);
1679 if (!arch_irn_consider_in_reg_alloc(cls, proj))
1681 assign_reg(block, proj, output_regs);
1683 } else if (arch_irn_consider_in_reg_alloc(cls, node)) {
1684 assign_reg(block, node, output_regs);
1688 ir_nodeset_destroy(&live_nodes);
1691 block_info->processed = true;
1693 /* permute values at end of predecessor blocks in case of phi-nodes */
1696 for (p = 0; p < n_preds; ++p) {
1697 add_phi_permutations(block, p);
1701 /* if we have exactly 1 successor then we might be able to produce phi
1703 if (get_irn_n_edges_kind(block, EDGE_KIND_BLOCK) == 1) {
1704 const ir_edge_t *edge
1705 = get_irn_out_edge_first_kind(block, EDGE_KIND_BLOCK);
1706 ir_node *succ = get_edge_src_irn(edge);
1707 int p = get_edge_src_pos(edge);
1708 block_info_t *succ_info = get_block_info(succ);
1710 if (succ_info->processed) {
1711 add_phi_permutations(succ, p);
1716 typedef struct block_costs_t block_costs_t;
1717 struct block_costs_t {
1718 float costs; /**< costs of the block */
1719 int dfs_num; /**< depth first search number (to detect backedges) */
1722 static int cmp_block_costs(const void *d1, const void *d2)
1724 const ir_node * const *block1 = d1;
1725 const ir_node * const *block2 = d2;
1726 const block_costs_t *info1 = get_irn_link(*block1);
1727 const block_costs_t *info2 = get_irn_link(*block2);
1728 return QSORT_CMP(info2->costs, info1->costs);
1731 static void determine_block_order(void)
1734 ir_node **blocklist = be_get_cfgpostorder(irg);
1735 int n_blocks = ARR_LEN(blocklist);
1737 pdeq *worklist = new_pdeq();
1738 ir_node **order = XMALLOCN(ir_node*, n_blocks);
1741 /* clear block links... */
1742 for (i = 0; i < n_blocks; ++i) {
1743 ir_node *block = blocklist[i];
1744 set_irn_link(block, NULL);
1747 /* walk blocks in reverse postorder, the costs for each block are the
1748 * sum of the costs of its predecessors (excluding the costs on backedges
1749 * which we can't determine) */
1750 for (i = n_blocks-1; i >= 0; --i) {
1751 block_costs_t *cost_info;
1752 ir_node *block = blocklist[i];
1754 float execfreq = get_block_execfreq(execfreqs, block);
1755 float costs = execfreq;
1756 int n_cfgpreds = get_Block_n_cfgpreds(block);
1758 for (p = 0; p < n_cfgpreds; ++p) {
1759 ir_node *pred_block = get_Block_cfgpred_block(block, p);
1760 block_costs_t *pred_costs = get_irn_link(pred_block);
1761 /* we don't have any info for backedges */
1762 if (pred_costs == NULL)
1764 costs += pred_costs->costs;
1767 cost_info = OALLOCZ(&obst, block_costs_t);
1768 cost_info->costs = costs;
1769 cost_info->dfs_num = dfs_num++;
1770 set_irn_link(block, cost_info);
1773 /* sort array by block costs */
1774 qsort(blocklist, n_blocks, sizeof(blocklist[0]), cmp_block_costs);
1776 ir_reserve_resources(irg, IR_RESOURCE_BLOCK_VISITED);
1777 inc_irg_block_visited(irg);
1779 for (i = 0; i < n_blocks; ++i) {
1780 ir_node *block = blocklist[i];
1781 if (Block_block_visited(block))
1784 /* continually add predecessors with highest costs to worklist
1785 * (without using backedges) */
1787 block_costs_t *info = get_irn_link(block);
1788 ir_node *best_pred = NULL;
1789 float best_costs = -1;
1790 int n_cfgpred = get_Block_n_cfgpreds(block);
1793 pdeq_putr(worklist, block);
1794 mark_Block_block_visited(block);
1795 for (i = 0; i < n_cfgpred; ++i) {
1796 ir_node *pred_block = get_Block_cfgpred_block(block, i);
1797 block_costs_t *pred_info = get_irn_link(pred_block);
1799 /* ignore backedges */
1800 if (pred_info->dfs_num > info->dfs_num)
1803 if (info->costs > best_costs) {
1804 best_costs = info->costs;
1805 best_pred = pred_block;
1809 } while(block != NULL && !Block_block_visited(block));
1811 /* now put all nodes in the worklist in our final order */
1812 while (!pdeq_empty(worklist)) {
1813 ir_node *pblock = pdeq_getr(worklist);
1814 assert(order_p < n_blocks);
1815 order[order_p++] = pblock;
1818 assert(order_p == n_blocks);
1821 ir_free_resources(irg, IR_RESOURCE_BLOCK_VISITED);
1823 DEL_ARR_F(blocklist);
1825 obstack_free(&obst, NULL);
1826 obstack_init(&obst);
1828 block_order = order;
1829 n_block_order = n_blocks;
1833 * Run the register allocator for the current register class.
1835 static void be_straight_alloc_cls(void)
1839 lv = be_assure_liveness(birg);
1840 be_liveness_assure_sets(lv);
1841 be_liveness_assure_chk(lv);
1843 ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
1845 DB((dbg, LEVEL_2, "=== Allocating registers of %s ===\n", cls->name));
1847 be_clear_links(irg);
1848 irg_block_walk_graph(irg, NULL, analyze_block, NULL);
1849 combine_congruence_classes();
1851 for (i = 0; i < n_block_order; ++i) {
1852 ir_node *block = block_order[i];
1853 allocate_coalesce_block(block, NULL);
1856 ir_free_resources(irg, IR_RESOURCE_IRN_LINK);
1859 static void dump(int mask, ir_graph *irg, const char *suffix,
1860 void (*dumper)(ir_graph *, const char *))
1862 if(birg->main_env->options->dump_flags & mask)
1863 be_dump(irg, suffix, dumper);
1867 * Run the spiller on the current graph.
1869 static void spill(void)
1871 /* make sure all nodes show their real register pressure */
1872 BE_TIMER_PUSH(t_ra_constr);
1873 be_pre_spill_prepare_constr(birg, cls);
1874 BE_TIMER_POP(t_ra_constr);
1876 dump(DUMP_RA, irg, "-spillprepare", dump_ir_block_graph_sched);
1879 BE_TIMER_PUSH(t_ra_spill);
1880 be_do_spill(birg, cls);
1881 BE_TIMER_POP(t_ra_spill);
1883 BE_TIMER_PUSH(t_ra_spill_apply);
1884 check_for_memory_operands(irg);
1885 BE_TIMER_POP(t_ra_spill_apply);
1887 dump(DUMP_RA, irg, "-spill", dump_ir_block_graph_sched);
1891 * The straight register allocator for a whole procedure.
1893 static void be_straight_alloc(be_irg_t *new_birg)
1895 const arch_env_t *arch_env = new_birg->main_env->arch_env;
1896 int n_cls = arch_env_get_n_reg_class(arch_env);
1899 obstack_init(&obst);
1902 irg = be_get_birg_irg(birg);
1903 execfreqs = birg->exec_freq;
1905 /* determine a good coloring order */
1906 determine_block_order();
1908 for (c = 0; c < n_cls; ++c) {
1909 cls = arch_env_get_reg_class(arch_env, c);
1910 default_cls_req = NULL;
1911 if (arch_register_class_flags(cls) & arch_register_class_flag_manual_ra)
1914 stat_ev_ctx_push_str("regcls", cls->name);
1916 n_regs = arch_register_class_n_regs(cls);
1917 normal_regs = rbitset_malloc(n_regs);
1918 be_abi_set_non_ignore_regs(birg->abi, cls, normal_regs);
1922 /* verify schedule and register pressure */
1923 BE_TIMER_PUSH(t_verify);
1924 if (birg->main_env->options->vrfy_option == BE_VRFY_WARN) {
1925 be_verify_schedule(birg);
1926 be_verify_register_pressure(birg, cls, irg);
1927 } else if (birg->main_env->options->vrfy_option == BE_VRFY_ASSERT) {
1928 assert(be_verify_schedule(birg) && "Schedule verification failed");
1929 assert(be_verify_register_pressure(birg, cls, irg)
1930 && "Register pressure verification failed");
1932 BE_TIMER_POP(t_verify);
1934 BE_TIMER_PUSH(t_ra_color);
1935 be_straight_alloc_cls();
1936 BE_TIMER_POP(t_ra_color);
1938 /* we most probably constructed new Phis so liveness info is invalid
1940 /* TODO: test liveness_introduce */
1941 be_liveness_invalidate(lv);
1944 stat_ev_ctx_pop("regcls");
1947 BE_TIMER_PUSH(t_ra_spill_apply);
1948 be_abi_fix_stack_nodes(birg->abi);
1949 BE_TIMER_POP(t_ra_spill_apply);
1951 BE_TIMER_PUSH(t_verify);
1952 if (birg->main_env->options->vrfy_option == BE_VRFY_WARN) {
1953 be_verify_register_allocation(birg);
1954 } else if (birg->main_env->options->vrfy_option == BE_VRFY_ASSERT) {
1955 assert(be_verify_register_allocation(birg)
1956 && "Register allocation invalid");
1958 BE_TIMER_POP(t_verify);
1960 obstack_free(&obst, NULL);
1964 * Initializes this module.
1966 void be_init_straight_alloc(void)
1968 static be_ra_t be_ra_straight = {
1972 FIRM_DBG_REGISTER(dbg, "firm.be.straightalloc");
1974 be_register_allocator("straight", &be_ra_straight);
1977 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_straight_alloc);