2 * Author: Christian Wuerdig
4 * Copyright: (c) Universitaet Karlsruhe
5 * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
8 * Performs lowering of perm nodes and spill/reload optimization.
23 #include "besched_t.h"
26 #include "irnodeset.h"
29 #include "iredges_t.h"
39 #undef KEEP_ALIVE_COPYKEEP_HACK
41 /* associates op with it's copy and CopyKeep */
43 ir_node *op; /* an irn which must be different */
44 ir_nodeset_t copies; /* all non-spillable copies of this irn */
45 const arch_register_class_t *cls;
48 /* environment for constraints */
53 DEBUG_ONLY(firm_dbg_module_t *dbg;)
56 /* lowering walker environment */
57 typedef struct _lower_env_t {
59 const arch_env_t *arch_env;
61 DEBUG_ONLY(firm_dbg_module_t *dbg_module;)
64 /* holds a perm register pair */
65 typedef struct _reg_pair_t {
66 const arch_register_t *in_reg; /**< a perm IN register */
67 ir_node *in_node; /**< the in node to which the register belongs */
69 const arch_register_t *out_reg; /**< a perm OUT register */
70 ir_node *out_node; /**< the out node to which the register belongs */
72 int checked; /**< indicates whether the pair was check for cycle or not */
75 typedef enum _perm_type_t {
82 /* structure to represent cycles or chains in a perm */
83 typedef struct _perm_cycle_t {
84 const arch_register_t **elems; /**< the registers in the cycle */
85 int n_elems; /**< number of elements in the cycle */
86 perm_type_t type; /**< type (CHAIN or CYCLE) */
89 /* Compare the two operands */
90 static int cmp_op_copy_assoc(const void *a, const void *b) {
91 const op_copy_assoc_t *op1 = a;
92 const op_copy_assoc_t *op2 = b;
94 return op1->op != op2->op;
97 /* Compare the in registers of two register pairs */
98 static int compare_reg_pair(const void *a, const void *b) {
99 const reg_pair_t *pair_a = a;
100 const reg_pair_t *pair_b = b;
102 if (pair_a->in_reg->index > pair_b->in_reg->index)
108 /* returns the number register pairs marked as checked */
109 static int get_n_checked_pairs(reg_pair_t *pairs, int n) {
110 int i, n_checked = 0;
112 for (i = 0; i < n; i++) {
113 if (pairs[i].checked)
121 * Gets the node corresponding to a register from an array of register pairs.
122 * NOTE: The given registers pairs and the register to look for must belong
123 * to the same register class.
125 * @param pairs The array of register pairs
126 * @param n The number of pairs
127 * @param reg The register to look for
128 * @param in_out 0 == look for IN register, 1 == look for OUT register
129 * @return The corresponding node or NULL if not found
131 static ir_node *get_node_for_register(reg_pair_t *pairs, int n, const arch_register_t *reg, int in_out) {
135 for (i = 0; i < n; i++) {
136 /* out register matches */
137 if (pairs[i].out_reg->index == reg->index)
138 return pairs[i].out_node;
142 for (i = 0; i < n; i++) {
143 /* in register matches */
144 if (pairs[i].in_reg->index == reg->index)
145 return pairs[i].in_node;
153 * Gets the index in the register pair array where the in/out register
154 * corresponds to reg_idx.
156 * @param pairs The array of register pairs
157 * @param n The number of pairs
158 * @param reg The register index to look for
159 * @param in_out 0 == look for IN register, 1 == look for OUT register
160 * @return The corresponding index in pairs or -1 if not found
162 static int get_pairidx_for_regidx(reg_pair_t *pairs, int n, int reg_idx, int in_out) {
166 for (i = 0; i < n; i++) {
167 /* out register matches */
168 if (pairs[i].out_reg->index == reg_idx)
173 for (i = 0; i < n; i++) {
174 /* in register matches */
175 if (pairs[i].in_reg->index == reg_idx)
184 * Gets an array of register pairs and tries to identify a cycle or chain starting
187 * @param cycle Variable to hold the cycle
188 * @param pairs Array of register pairs
189 * @param start Index to start
190 * @return The cycle or chain
192 static perm_cycle_t *get_perm_cycle(perm_cycle_t *cycle, reg_pair_t *pairs, int n, int start) {
193 int head = pairs[start].in_reg->index;
194 int cur_idx = pairs[start].out_reg->index;
195 int cur_pair_idx = start;
196 int n_pairs_done = get_n_checked_pairs(pairs, n);
198 perm_type_t cycle_tp = PERM_CYCLE;
200 /* We could be right in the middle of a chain, so we need to find the start */
201 while (head != cur_idx) {
202 /* goto previous register in cycle or chain */
203 cur_pair_idx = get_pairidx_for_regidx(pairs, n, head, 1);
205 if (cur_pair_idx < 0) {
206 cycle_tp = PERM_CHAIN;
210 head = pairs[cur_pair_idx].in_reg->index;
211 start = cur_pair_idx;
215 /* assume worst case: all remaining pairs build a cycle or chain */
216 cycle->elems = xcalloc((n - n_pairs_done) * 2, sizeof(cycle->elems[0]));
217 cycle->n_elems = 2; /* initial number of elements is 2 */
218 cycle->elems[0] = pairs[start].in_reg;
219 cycle->elems[1] = pairs[start].out_reg;
220 cycle->type = cycle_tp;
221 cur_idx = pairs[start].out_reg->index;
224 /* check for cycle or end of a chain */
225 while (cur_idx != head) {
226 /* goto next register in cycle or chain */
227 cur_pair_idx = get_pairidx_for_regidx(pairs, n, cur_idx, 0);
229 if (cur_pair_idx < 0)
232 cur_idx = pairs[cur_pair_idx].out_reg->index;
234 /* it's not the first element: insert it */
235 if (cur_idx != head) {
236 cycle->elems[idx++] = pairs[cur_pair_idx].out_reg;
240 /* we are there where we started -> CYCLE */
241 cycle->type = PERM_CYCLE;
245 /* mark all pairs having one in/out register with cycle in common as checked */
246 for (idx = 0; idx < cycle->n_elems; idx++) {
247 cur_pair_idx = get_pairidx_for_regidx(pairs, n, cycle->elems[idx]->index, 0);
249 if (cur_pair_idx >= 0)
250 pairs[cur_pair_idx].checked = 1;
252 cur_pair_idx = get_pairidx_for_regidx(pairs, n, cycle->elems[idx]->index, 1);
254 if (cur_pair_idx >= 0)
255 pairs[cur_pair_idx].checked = 1;
262 * Lowers a perm node. Resolves cycles and creates a bunch of
263 * copy and swap operations to permute registers.
264 * Note: The caller of this function has to make sure, that irn
267 * @param irn The perm node
268 * @param block The block the perm node belongs to
269 * @param walk_env The environment
271 static void lower_perm_node(ir_node *irn, void *walk_env) {
272 const arch_register_class_t *reg_class;
273 const arch_env_t *arch_env;
274 lower_env_t *env = walk_env;
277 int n, i, pn, do_copy, j, n_ops;
279 const ir_edge_t *edge;
281 ir_node *sched_point, *block, *in[2];
282 ir_node *arg1, *arg2, *res1, *res2;
283 ir_node *cpyxchg = NULL;
284 DEBUG_ONLY(firm_dbg_module_t *mod;)
286 arch_env = env->arch_env;
287 do_copy = env->do_copy;
288 DEBUG_ONLY(mod = env->dbg_module;)
289 block = get_nodes_block(irn);
292 Get the schedule predecessor node to the perm
293 NOTE: This works with auto-magic. If we insert the
294 new copy/exchange nodes after this node, everything
297 sched_point = sched_prev(irn);
298 DBG((mod, LEVEL_1, "sched point is %+F\n", sched_point));
299 assert(sched_point && "Perm is not scheduled or has no predecessor");
301 n = get_irn_arity(irn);
302 assert(n == get_irn_n_edges(irn) && "perm's in and out numbers different");
304 reg_class = arch_get_irn_register(arch_env, get_irn_n(irn, 0))->reg_class;
305 pairs = alloca(n * sizeof(pairs[0]));
307 /* build the list of register pairs (in, out) */
309 foreach_out_edge(irn, edge) {
310 pairs[i].out_node = get_edge_src_irn(edge);
311 pn = get_Proj_proj(pairs[i].out_node);
312 pairs[i].in_node = get_irn_n(irn, pn);
314 pairs[i].in_reg = arch_get_irn_register(arch_env, pairs[i].in_node);
315 pairs[i].out_reg = arch_get_irn_register(arch_env, pairs[i].out_node);
317 pairs[i].checked = 0;
321 /* sort the register pairs by the indices of the in registers */
322 qsort(pairs, n, sizeof(pairs[0]), compare_reg_pair);
324 /* Mark all equal pairs as checked, and exchange the OUT proj with
326 for (i = 0; i < n; i++) {
327 if (pairs[i].in_reg->index == pairs[i].out_reg->index) {
328 DBG((mod, LEVEL_1, "%+F removing equal perm register pair (%+F, %+F, %s)\n",
329 irn, pairs[i].in_node, pairs[i].out_node, pairs[i].out_reg->name));
331 /* We have to check for a special case:
332 The in-node could be a Proj from a Perm. In this case,
333 we need to correct the projnum */
334 if (be_is_Perm(pairs[i].in_node) && is_Proj(pairs[i].in_node)) {
335 set_Proj_proj(pairs[i].out_node, get_Proj_proj(pairs[i].in_node));
338 /* remove the proj from the schedule */
339 sched_remove(pairs[i].out_node);
341 /* reroute the edges from the proj to the argument */
342 exchange(pairs[i].out_node, pairs[i].in_node);
343 //edges_reroute(pairs[i].out_node, pairs[i].in_node, env->birg->irg);
344 //set_irn_n(pairs[i].out_node, 0, new_Bad());
346 pairs[i].checked = 1;
350 /* Set do_copy to 0 if it's on but we have no free register */
355 real_size = n - get_n_checked_pairs(pairs, n);
357 be_do_stat_perm(reg_class->name, reg_class->n_regs, irn, block, n, real_size);
359 /* check for cycles and chains */
360 while (get_n_checked_pairs(pairs, n) < n) {
363 /* go to the first not-checked pair */
364 while (pairs[i].checked) i++;
365 cycle = xcalloc(1, sizeof(*cycle));
366 cycle = get_perm_cycle(cycle, pairs, n, i);
368 DB((mod, LEVEL_1, "%+F: following %s created:\n ", irn, cycle->type == PERM_CHAIN ? "chain" : "cycle"));
369 for (j = 0; j < cycle->n_elems; j++) {
370 DB((mod, LEVEL_1, " %s", cycle->elems[j]->name));
372 DB((mod, LEVEL_1, "\n"));
375 We don't need to do anything if we have a Perm with two
376 elements which represents a cycle, because those nodes
377 already represent exchange nodes
379 if (n == 2 && cycle->type == PERM_CYCLE) {
385 //TODO: - iff PERM_CYCLE && do_copy -> determine free temp reg and insert copy to/from it before/after
386 // the copy cascade (this reduces the cycle into a chain)
388 /* build copy/swap nodes from back to front */
389 for (i = cycle->n_elems - 2; i >= 0; i--) {
390 arg1 = get_node_for_register(pairs, n, cycle->elems[i], 0);
391 arg2 = get_node_for_register(pairs, n, cycle->elems[i + 1], 0);
393 res1 = get_node_for_register(pairs, n, cycle->elems[i], 1);
394 res2 = get_node_for_register(pairs, n, cycle->elems[i + 1], 1);
396 If we have a cycle and don't copy: we need to create exchange nodes
397 NOTE: An exchange node is a perm node with 2 INs and 2 OUTs
398 IN_1 = in node with register i
399 IN_2 = in node with register i + 1
400 OUT_1 = out node with register i + 1
401 OUT_2 = out node with register i
403 if (cycle->type == PERM_CYCLE && !do_copy) {
407 /* At this point we have to handle the following problem: */
409 /* If we have a cycle with more than two elements, then */
410 /* this could correspond to the following Perm node: */
412 /* +----+ +----+ +----+ */
413 /* | r1 | | r2 | | r3 | */
414 /* +-+--+ +-+--+ +--+-+ */
417 /* +-+--------+---------+-+ */
419 /* +-+--------+---------+-+ */
422 /* +-+--+ +-+--+ +--+-+ */
423 /* |Proj| |Proj| |Proj| */
424 /* | r2 | | r3 | | r1 | */
425 /* +----+ +----+ +----+ */
427 /* This node is about to be split up into two 2x Perm's */
428 /* for which we need 4 Proj's and the one additional Proj */
429 /* of the first Perm has to be one IN of the second. So in */
430 /* general we need to create one additional Proj for each */
431 /* "middle" Perm and set this to one in node of the successor */
434 DBG((mod, LEVEL_1, "%+F creating exchange node (%+F, %s) and (%+F, %s) with\n",
435 irn, arg1, cycle->elems[i]->name, arg2, cycle->elems[i + 1]->name));
436 DBG((mod, LEVEL_1, "%+F (%+F, %s) and (%+F, %s)\n",
437 irn, res1, cycle->elems[i]->name, res2, cycle->elems[i + 1]->name));
439 cpyxchg = be_new_Perm(reg_class, env->birg->irg, block, 2, in);
443 /* cycle is not done yet */
444 int pidx = get_pairidx_for_regidx(pairs, n, cycle->elems[i]->index, 0);
446 /* create intermediate proj */
447 res1 = new_r_Proj(get_irn_irg(irn), block, cpyxchg, get_irn_mode(res1), 0);
449 /* set as in for next Perm */
450 pairs[pidx].in_node = res1;
458 set_Proj_pred(res2, cpyxchg);
459 set_Proj_proj(res2, 0);
460 set_Proj_pred(res1, cpyxchg);
461 set_Proj_proj(res1, 1);
463 sched_add_after(sched_point, res1);
464 sched_add_after(sched_point, res2);
466 arch_set_irn_register(arch_env, res2, cycle->elems[i + 1]);
467 arch_set_irn_register(arch_env, res1, cycle->elems[i]);
469 /* insert the copy/exchange node in schedule after the magic schedule node (see above) */
470 sched_add_after(sched_point, cpyxchg);
472 DBG((mod, LEVEL_1, "replacing %+F with %+F, placed new node after %+F\n", irn, cpyxchg, sched_point));
474 /* set the new scheduling point */
478 DBG((mod, LEVEL_1, "%+F creating copy node (%+F, %s) -> (%+F, %s)\n",
479 irn, arg1, cycle->elems[i]->name, res2, cycle->elems[i + 1]->name));
481 cpyxchg = be_new_Copy(reg_class, env->birg->irg, block, arg1);
482 arch_set_irn_register(arch_env, cpyxchg, cycle->elems[i + 1]);
485 /* remove the proj from the schedule */
488 /* exchange copy node and proj */
489 exchange(res2, cpyxchg);
491 /* insert the copy/exchange node in schedule after the magic schedule node (see above) */
492 sched_add_after(sched_point, cpyxchg);
494 /* set the new scheduling point */
495 sched_point = cpyxchg;
499 be_do_stat_permcycle(reg_class->name, irn, block, cycle->type == PERM_CHAIN, cycle->n_elems, n_ops);
501 free((void *) cycle->elems);
505 /* remove the perm from schedule */
514 static int get_n_out_edges(const ir_node *irn) {
515 const ir_edge_t *edge;
518 foreach_out_edge(irn, edge) {
525 static ir_node *belower_skip_proj(ir_node *irn) {
527 irn = get_Proj_pred(irn);
531 static ir_node *find_copy(constraint_env_t *env, ir_node *irn, ir_node *op) {
532 const arch_env_t *arch_env = env->birg->main_env->arch_env;
533 ir_node *block = get_nodes_block(irn);
536 for (cur_node = sched_prev(irn);
537 ! is_Block(cur_node) && be_is_Copy(cur_node) && get_nodes_block(cur_node) == block;
538 cur_node = sched_prev(cur_node))
540 if (be_get_Copy_op(cur_node) == op && arch_irn_is(arch_env, cur_node, dont_spill))
547 static void gen_assure_different_pattern(ir_node *irn, ir_node *other_different, constraint_env_t *env) {
548 be_irg_t *birg = env->birg;
549 pset *op_set = env->op_set;
550 const arch_env_t *arch_env = birg->main_env->arch_env;
551 ir_node *block = get_nodes_block(irn);
552 const arch_register_class_t *cls = arch_get_irn_reg_class(arch_env, other_different, -1);
553 ir_node *in[2], *keep, *cpy;
554 op_copy_assoc_t key, *entry;
555 DEBUG_ONLY(firm_dbg_module_t *mod = env->dbg;)
557 if (arch_irn_is(arch_env, other_different, ignore) || ! mode_is_datab(get_irn_mode(other_different))) {
558 DBG((mod, LEVEL_1, "ignore constraint for %+F because other_irn is ignore or not a datab node\n", irn));
562 /* Make a not spillable copy of the different node */
563 /* this is needed because the different irn could be */
564 /* in block far far away */
565 /* The copy is optimized later if not needed */
567 /* check if already exists such a copy in the schedule immediatly before */
568 cpy = find_copy(env, belower_skip_proj(irn), other_different);
570 cpy = be_new_Copy(cls, birg->irg, block, other_different);
571 be_node_set_flags(cpy, BE_OUT_POS(0), arch_irn_flags_dont_spill);
572 DBG((mod, LEVEL_1, "created non-spillable %+F for value %+F\n", cpy, other_different));
575 DBG((mod, LEVEL_1, "using already existing %+F for value %+F\n", cpy, other_different));
581 /* Add the Keep resp. CopyKeep and reroute the users */
582 /* of the other_different irn in case of CopyKeep. */
583 if (get_n_out_edges(other_different) == 0) {
584 keep = be_new_Keep(cls, birg->irg, block, 2, in);
587 keep = be_new_CopyKeep_single(cls, birg->irg, block, cpy, irn, get_irn_mode(other_different));
588 be_node_set_reg_class(keep, 1, cls);
591 DBG((mod, LEVEL_1, "created %+F(%+F, %+F)\n\n", keep, irn, cpy));
593 /* insert copy and keep into schedule */
594 assert(sched_is_scheduled(irn) && "need schedule to assure constraints");
595 if (! sched_is_scheduled(cpy))
596 sched_add_before(belower_skip_proj(irn), cpy);
597 sched_add_after(irn, keep);
599 /* insert the other different and it's copies into the set */
600 key.op = other_different;
601 entry = pset_find(op_set, &key, nodeset_hash(other_different));
604 entry = obstack_alloc(&env->obst, sizeof(*entry));
605 ir_nodeset_init(&entry->copies);
606 entry->op = other_different;
611 ir_nodeset_insert(&entry->copies, cpy);
613 /* insert keep in case of CopyKeep */
614 if (be_is_CopyKeep(keep)) {
615 ir_nodeset_insert(&entry->copies, keep);
618 pset_insert(op_set, entry, nodeset_hash(other_different));
622 * Checks if node has a should_be_different constraint in output
623 * and adds a Keep then to assure the constraint.
625 static void assure_different_constraints(ir_node *irn, constraint_env_t *env) {
626 const arch_register_req_t *req;
628 req = arch_get_register_req(env->birg->main_env->arch_env, irn, -1);
630 if (arch_register_req_is(req, should_be_different)) {
631 ir_node *different_from = get_irn_n(irn, req->other_different);
632 gen_assure_different_pattern(irn, different_from, env);
633 } else if (arch_register_req_is(req, should_be_different_from_all)) {
634 int i, n = get_irn_arity(belower_skip_proj(irn));
635 for (i = 0; i < n; i++) {
636 gen_assure_different_pattern(irn, get_irn_n(belower_skip_proj(irn), i), env);
644 * Calls the functions to assure register constraints.
646 * @param irn The node to be checked for lowering
647 * @param walk_env The walker environment
649 static void assure_constraints_walker(ir_node *irn, void *walk_env) {
653 if (sched_is_scheduled(irn) && mode_is_datab(get_irn_mode(irn)))
654 assure_different_constraints(irn, walk_env);
660 * Melt all copykeeps pointing to the same node
661 * (or Projs of the same node), copying the same operand.
663 static void melt_copykeeps(constraint_env_t *cenv) {
664 op_copy_assoc_t *entry;
667 foreach_pset(cenv->op_set, entry) {
671 ir_nodeset_iterator_t iter;
672 ir_node **ck_arr, **melt_arr;
676 /* collect all copykeeps */
678 foreach_ir_nodeset(&entry->copies, cp, iter) {
679 if (be_is_CopyKeep(cp)) {
680 obstack_grow(&obst, &cp, sizeof(cp));
683 #ifdef KEEP_ALIVE_COPYKEEP_HACK
685 set_irn_mode(cp, mode_ANY);
688 #endif /* KEEP_ALIVE_COPYKEEP_HACK */
691 /* compare each copykeep with all other copykeeps */
692 ck_arr = (ir_node **)obstack_finish(&obst);
693 for (idx = 0; idx < num_ck; ++idx) {
694 ir_node *ref, *ref_mode_T;
700 ir_node *sched_pt = NULL;
704 ref_mode_T = skip_Proj(get_irn_n(ref, 1));
705 obstack_grow(&obst, &ref, sizeof(ref));
707 DBG((cenv->dbg, LEVEL_1, "Trying to melt %+F:\n", ref));
709 /* check for copykeeps pointing to the same mode_T node as the reference copykeep */
710 for (j = 0; j < num_ck; ++j) {
711 ir_node *cur_ck = ck_arr[j];
713 if (j != idx && cur_ck && skip_Proj(get_irn_n(cur_ck, 1)) == ref_mode_T) {
714 obstack_grow(&obst, &cur_ck, sizeof(cur_ck));
715 ir_nodeset_remove(&entry->copies, cur_ck);
716 DBG((cenv->dbg, LEVEL_1, "\t%+F\n", cur_ck));
719 sched_remove(cur_ck);
724 /* check, if we found some candidates for melting */
726 DBG((cenv->dbg, LEVEL_1, "\tno candidate found\n"));
730 ir_nodeset_remove(&entry->copies, ref);
733 melt_arr = (ir_node **)obstack_finish(&obst);
734 /* melt all found copykeeps */
735 NEW_ARR_A(ir_node *, new_ck_in, n_melt);
736 for (j = 0; j < n_melt; ++j) {
737 new_ck_in[j] = get_irn_n(melt_arr[j], 1);
739 /* now, we can kill the melted keep, except the */
740 /* ref one, we still need some information */
741 if (melt_arr[j] != ref)
742 be_kill_node(melt_arr[j]);
745 #ifdef KEEP_ALIVE_COPYKEEP_HACK
746 new_ck = be_new_CopyKeep(entry->cls, cenv->birg->irg, get_nodes_block(ref), be_get_CopyKeep_op(ref), n_melt, new_ck_in, mode_ANY);
749 new_ck = be_new_CopyKeep(entry->cls, cenv->birg->irg, get_nodes_block(ref), be_get_CopyKeep_op(ref), n_melt, new_ck_in, get_irn_mode(ref));
750 #endif /* KEEP_ALIVE_COPYKEEP_HACK */
752 /* set register class for all keeped inputs */
753 for (j = 1; j <= n_melt; ++j)
754 be_node_set_reg_class(new_ck, j, entry->cls);
756 ir_nodeset_insert(&entry->copies, new_ck);
758 /* find scheduling point */
759 if (get_irn_mode(ref_mode_T) == mode_T) {
760 /* walk along the Projs */
761 for (sched_pt = sched_next(ref_mode_T); is_Proj(sched_pt) || be_is_Keep(sched_pt) || be_is_CopyKeep(sched_pt); sched_pt = sched_next(sched_pt))
762 /* just walk along the schedule until a non-Proj/Keep/CopyKeep node is found*/ ;
765 sched_pt = ref_mode_T;
768 sched_add_before(sched_pt, new_ck);
769 DBG((cenv->dbg, LEVEL_1, "created %+F, scheduled before %+F\n", new_ck, sched_pt));
771 /* finally: kill the reference copykeep */
776 obstack_free(&obst, NULL);
781 * Walks over all nodes to assure register constraints.
783 * @param birg The birg structure containing the irg
785 void assure_constraints(be_irg_t *birg) {
786 constraint_env_t cenv;
787 op_copy_assoc_t *entry;
789 FIRM_DBG_REGISTER(firm_dbg_module_t *mod, "firm.be.lower.constr");
791 be_assure_dom_front(birg);
793 DEBUG_ONLY(cenv.dbg = mod;)
795 cenv.op_set = new_pset(cmp_op_copy_assoc, 16);
796 obstack_init(&cenv.obst);
798 irg_walk_blkwise_graph(birg->irg, NULL, assure_constraints_walker, &cenv);
800 /* melt copykeeps, pointing to projs of */
801 /* the same mode_T node and keeping the */
803 melt_copykeeps(&cenv);
806 foreach_pset(cenv.op_set, entry) {
809 ir_nodeset_iterator_t iter;
811 n = ir_nodeset_size(&entry->copies);
812 nodes = alloca(n * sizeof(nodes[0]));
814 /* put the node in an array */
815 DBG((mod, LEVEL_1, "introduce copies for %+F ", entry->op));
817 /* collect all copies */
819 foreach_ir_nodeset(&entry->copies, cp, iter) {
821 DB((mod, LEVEL_1, ", %+F ", cp));
824 DB((mod, LEVEL_1, "\n"));
826 /* introduce the copies for the operand and it's copies */
827 be_ssa_construction(birg->dom_front, NULL, entry->op,
831 /* Could be that not all CopyKeeps are really needed, */
832 /* so we transform unnecessary ones into Keeps. */
833 foreach_ir_nodeset(&entry->copies, cp, iter) {
834 if (be_is_CopyKeep(cp) && get_irn_n_edges(cp) < 1) {
836 int n = get_irn_arity(cp);
838 keep = be_new_Keep(arch_get_irn_reg_class(birg->main_env->arch_env, cp, -1),
839 birg->irg, get_nodes_block(cp), n, (ir_node **)&get_irn_in(cp)[1]);
840 sched_add_before(cp, keep);
842 /* Set all ins (including the block) of the CopyKeep BAD to keep the verifier happy. */
848 ir_nodeset_destroy(&entry->copies);
851 del_pset(cenv.op_set);
852 obstack_free(&cenv.obst, NULL);
853 be_invalidate_liveness(birg);
859 * Calls the corresponding lowering function for the node.
861 * @param irn The node to be checked for lowering
862 * @param walk_env The walker environment
864 static void lower_nodes_after_ra_walker(ir_node *irn, void *walk_env) {
865 if (! is_Block(irn) && ! is_Proj(irn)) {
866 if (be_is_Perm(irn)) {
867 lower_perm_node(irn, walk_env);
875 * Walks over all blocks in an irg and performs lowering need to be
876 * done after register allocation (e.g. perm lowering).
878 * @param birg The birg object
879 * @param do_copy 1 == resolve cycles with a free reg if available
881 void lower_nodes_after_ra(be_irg_t *birg, int do_copy) {
885 env.arch_env = birg->main_env->arch_env;
886 env.do_copy = do_copy;
887 FIRM_DBG_REGISTER(env.dbg_module, "firm.be.lower");
889 irg_walk_blkwise_graph(birg->irg, NULL, lower_nodes_after_ra_walker, &env);