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 Implementation of the RA-Interface for an external, (non-SSA) register allocator.
23 * @author Daniel Grund
27 * The external register allocator is a program:
28 * PROG -i INPUTFILE -o OUTPUTFILE
30 * 1) Input file defines the interference graph
31 * 2) Output file contains the instructions to perform
36 ----------------------
38 inputfile ::= regs nodes interf affinities .
40 regs ::= 'regs' regcount . // Anzahl der register (0..regcount-1), die zur Verfuegung stehen
42 nodes ::= 'nodes' '{' node* '}' . // All nodes in the graph
45 | node-info '<' reg-nr '>' . // Reg-nr is present in case of constraints
47 node-info ::= node-nr spill-costs .
49 interf ::= 'interferences' '{' i-edge* '}' . // Interference edges of the graph
51 i-edge ::= '(' node-nr ',' node-nr ')' .
53 affinities ::= 'affinities' '{' a-edge* '}' . // Affinity edges of the graph
55 a-edge ::= '(' node-nr ',' node-nr ',' weight ')' .
58 weight, regcount, node-nr ::= int32 .
59 spill-costs ::= int32 . // negative spill costs indicate unspillable
61 The output file format
62 -----------------------
64 outputfile ::= spills | allocs .
66 spills ::= 'spills' node-nr+ .
68 allocs ::= 'allocs' alloc* .
70 alloc ::= node-nr reg-nr .
82 #include "lc_opts_enum.h"
88 #include "raw_bitset.h"
91 #include "irprintf_t.h"
93 #include "irgraph_t.h"
95 #include "iredges_t.h"
101 #include "bearch_t.h"
102 #include "benode_t.h"
103 #include "beirgmod.h"
104 #include "besched_t.h"
106 #include "belive_t.h"
107 #include "beinsn_t.h"
109 #include "bessadestrsimple.h"
114 * Environment with all the needed stuff
116 typedef struct _be_raext_env_t {
118 const arch_register_class_t *cls;
122 FILE *f; /**< file handle used for out- and input file */
123 set *vars; /**< contains all be_var_info_t */
124 int n_cls_vars; /**< length of the array cls_vars */
125 be_var_info_t **cls_vars; /**< only the var_infos for current cls. needed for double iterating */
126 DEBUG_ONLY(firm_dbg_module_t *dbg;)
131 /******************************************************************************
134 | |__| | ___| |_ __ ___ _ __ ___
135 | __ |/ _ \ | '_ \ / _ \ '__/ __|
136 | | | | __/ | |_) | __/ | \__ \
137 |_| |_|\___|_| .__/ \___|_| |___/
140 *****************************************************************************/
143 #define pset_foreach(pset, irn) for(irn=pset_first(pset); irn; irn=pset_next(pset))
144 #define set_foreach(set, e) for(e=set_first(set); e; e=set_next(set))
147 * Checks if _the_ result of the irn belongs to the
148 * current register class (raenv->cls)
149 * NOTE: Only the first result is checked.
151 #define is_res_in_reg_class(irn) arch_irn_has_reg_class(raenv->aenv, irn, -1, raenv->cls)
153 static INLINE ir_node *get_first_non_phi(pset *s) {
162 assert(0 && "There must be a non-phi-irn in this");
166 static INLINE ir_node *get_first_phi(pset *s) {
175 assert(0 && "There must be a phi in this");
179 static int get_loop_weight(ir_node *irn) {
181 ir_loop *loop = get_irn_loop(get_nodes_block(irn));
184 int d = get_loop_depth(loop);
190 #define get_const_weight(irn) (1)
192 #define get_spill_weight(irn) get_loop_weight(irn)
193 #define get_reload_weight(irn) get_loop_weight(irn)
194 #define get_affinity_weight(irn) get_loop_weight(irn)
196 /******************************************************************************
198 / ____| | | / ____| (_)
199 | | ___ _ __ ___| |_ _ __ | | ___ _ __ _ ___ ___
200 | | / _ \| '_ \/ __| __| '__| | | / _ \| '_ \| |/ _ \/ __|
201 | |___| (_) | | | \__ \ |_| | | |___| (_) | |_) | | __/\__ \
202 \_____\___/|_| |_|___/\__|_| \_____\___/| .__/|_|\___||___/
205 *****************************************************************************/
207 static void handle_constraints_insn(be_raext_env_t *env, be_insn_t *insn)
209 ir_node *bl = get_nodes_block(insn->irn);
212 for(i = 0; i < insn->use_start; ++i) {
213 be_operand_t *op = &insn->ops[i];
215 if(op->has_constraints) {
216 ir_node *cpy = be_new_Copy(op->req->cls, env->irg, bl, op->carrier);
217 sched_add_before(insn->next_insn, cpy);
218 edges_reroute(op->carrier, cpy, env->irg);
222 for(i = insn->use_start; i < insn->n_ops; ++i) {
223 be_operand_t *op = &insn->ops[i];
225 if(op->has_constraints) {
226 ir_node *cpy = be_new_Copy(op->req->cls, env->irg, bl, op->carrier);
227 sched_add_before(insn->irn, cpy);
228 set_irn_n(insn->irn, op->pos, cpy);
229 be_set_constr_limited(cpy, BE_OUT_POS(0), op->req);
234 static void handle_constraints_block(ir_node *bl, void *data)
236 be_raext_env_t *raenv = data;
237 int active = bl != get_irg_start_block(raenv->irg);
244 ie.aenv = raenv->aenv;
246 ie.ignore_colors = NULL;
249 irn = sched_first(bl);
250 while(!sched_is_end(irn)) {
251 be_insn_t *insn = be_scan_insn(&ie, irn);
253 if(insn->has_constraints)
254 handle_constraints_insn(raenv, insn);
256 if(be_is_Barrier(irn))
259 irn = insn->next_insn;
260 obstack_free(&obst, insn);
264 static void handle_constraints(be_raext_env_t *raenv) {
265 irg_block_walk_graph(raenv->irg, NULL, handle_constraints_block, raenv);
271 /******************************************************************************
274 | | | |_ _ _ __ ___ _ __ ___ _ __
275 | | | | | | | '_ ` _ \| '_ \ / _ \ '__|
276 | |__| | |_| | | | | | | |_) | __/ |
277 |_____/ \__,_|_| |_| |_| .__/ \___|_|
280 *****************************************************************************/
283 static void extract_vars_of_cls(be_raext_env_t *raenv) {
287 raenv->cls_vars = xmalloc(set_count(raenv->vars) * sizeof(*raenv->cls_vars));
288 assert(raenv->cls_vars);
290 set_foreach(raenv->vars, vi)
291 if (is_res_in_reg_class(get_first_non_phi(vi->values)))
292 raenv->cls_vars[count++] = vi;
294 raenv->cls_vars = realloc(raenv->cls_vars, count * sizeof(*raenv->cls_vars));
295 assert(raenv->cls_vars);
297 raenv->n_cls_vars = count;
302 * Check if node irn has a limited-constraint at position pos.
303 * If yes, dump it to FILE raenv->f
305 static INLINE void dump_constraint(be_raext_env_t *raenv, ir_node *irn, int pos) {
306 const arch_register_req_t *req;
308 req = arch_get_register_req(raenv->aenv, irn, pos);
309 if (arch_register_req_is(req, limited)) {
312 reg_nr = rbitset_next(req->limited, 0, 1);
313 fprintf(raenv->f, "<%d>", reg_nr);
314 assert(rbitset_popcnt(req->limited, raenv->cls->n_regs) <= 1
315 && "Constraints with more than 1 possible register are not supported");
319 #define UNSPILLABLE -1
321 static INLINE int get_spill_costs(be_raext_env_t *raenv, be_var_info_t *vi) {
323 int c_spills=0, c_reloads=0;
325 pset_foreach(vi->values, irn) {
326 if (arch_irn_is(raenv->aenv, irn, ignore) || be_is_Reload(irn)) {
327 pset_break(vi->values);
332 /* number of reloads is the number of non-phi uses of all values of this var */
333 const ir_edge_t *edge;
334 foreach_out_edge(irn, edge)
335 if (!is_Phi(edge->src))
336 c_reloads += get_reload_weight(edge->src);
338 /* number of spills is the number of non-phi values for this var */
339 c_spills += get_spill_weight(irn);
343 return c_spills + c_reloads;
346 static void dump_nodes(be_raext_env_t *raenv) {
350 fprintf(f, "\nnodes {\n");
352 for (i=0; i<raenv->n_cls_vars; ++i) {
353 be_var_info_t *vi = raenv->cls_vars[i];
355 if (vi->var_nr == SET_REMOVED)
358 fprintf(f, "%d %d", vi->var_nr, get_spill_costs(raenv, vi));
359 dump_constraint(raenv, get_first_non_phi(vi->values), -1);
368 static void dump_interferences(be_raext_env_t *raenv) {
370 be_var_info_t *vi1, *vi2;
371 ir_node *irn1, *irn2;
373 be_lv_t *lv = raenv->birg->lv;
375 fprintf(f, "\ninterferences {\n");
377 for (i=0; i<raenv->n_cls_vars; ++i) {
378 vi1 = raenv->cls_vars[i];
380 if (vi1->var_nr == SET_REMOVED)
383 for (o=i+1; o<raenv->n_cls_vars; ++o) {
384 vi2 = raenv->cls_vars[o];
386 if (vi2->var_nr == SET_REMOVED)
389 pset_foreach(vi1->values, irn1)
390 pset_foreach(vi2->values, irn2)
391 if (values_interfere(lv, irn1, irn2)) {
392 pset_break(vi1->values);
393 pset_break(vi2->values);
394 fprintf(f, "(%d, %d)\n", vi1->var_nr, vi2->var_nr);
404 static void dump_affinities_walker(ir_node *irn, void *env) {
405 be_raext_env_t *raenv = env;
406 const arch_register_req_t *req;
408 be_var_info_t *vi1, *vi2;
410 if (arch_get_irn_reg_class(raenv->aenv, irn, -1) != raenv->cls || arch_irn_is(raenv->aenv, irn, ignore))
413 vi1 = be_get_var_info(irn);
415 /* copies have affinities */
416 if (arch_irn_class_is(raenv->aenv, irn, copy)) {
417 ir_node *other = be_get_Copy_op(irn);
419 if (! arch_irn_is(raenv->aenv, other, ignore)) {
420 vi2 = be_get_var_info(other);
422 fprintf(raenv->f, "(%d, %d, %d)\n", vi1->var_nr, vi2->var_nr, get_affinity_weight(irn));
427 /* should_be_equal constraints are affinites */
428 for (pos = 0, max = get_irn_arity(irn); pos<max; ++pos) {
429 req = arch_get_register_req(raenv->aenv, irn, pos);
430 if (arch_register_req_is(req, should_be_same)) {
432 for (i = req->other_same; i != ENDOF(req->other_same); ++i) {
437 other = get_irn_n(skip_Proj(irn), *i);
438 if(arch_irn_is(raenv->aenv, other, ignore)) {
439 vi2 = be_get_var_info(other);
440 fprintf(raenv->f, "(%d, %d, %d)\n", vi1->var_nr, vi2->var_nr, get_affinity_weight(irn));
448 static void dump_affinities(be_raext_env_t *raenv) {
449 fprintf(raenv->f, "\naffinities {\n");
450 irg_walk_graph(raenv->irg, NULL, dump_affinities_walker, raenv);
451 fprintf(raenv->f, "}\n");
455 * Dump all information needed by the external
456 * register allocator to a single file.
458 static void dump_to_file(be_raext_env_t *raenv, char *filename) {
461 if (!(f = fopen(filename, "wt"))) {
462 fprintf(stderr, "Could not open file %s for writing\n", filename);
467 /* dump register info */
468 fprintf(f, "regs %d\n", arch_register_class_n_regs(raenv->cls));
470 /* dump the interference graph */
472 dump_interferences(raenv);
473 dump_affinities(raenv);
478 /******************************************************************************
481 | |__ __ _____ ___ _ _| |_ ___
482 | __| \ \/ / _ \/ __| | | | __/ _ \
483 | |____ > < __/ (__| |_| | || __/
484 |______/_/\_\___|\___|\__,_|\__\___|
485 *****************************************************************************/
488 * Execute the external register allocator specified in the
489 * firm-option firm.be.ra.ext.callee
491 static void execute(char *prog_to_call, char *out_file, char *result_file) {
495 snprintf(cmd_line, sizeof(cmd_line), "%s -i %s -o %s", prog_to_call, out_file, result_file);
496 cmd_line[sizeof(cmd_line) - 1] = '\0';
498 ret_status = system(cmd_line);
499 assert(ret_status != -1 && "Invokation of external register allocator failed");
500 assert(ret_status == 0 && "External register allocator is unhappy with sth.");
503 /******************************************************************************
506 / \ _ __ _ __ | |_ _ | |__) |___ ___ _ _| | |_
507 / /\ \ | '_ \| '_ \| | | | | | _ // _ \/ __| | | | | __|
508 / ____ \| |_) | |_) | | |_| | | | \ \ __/\__ \ |_| | | |_
509 /_/ \_\ .__/| .__/|_|\__, | |_| \_\___||___/\__,_|_|\__|
512 *****************************************************************************/
515 * Spill a variable and add reloads before all uses.
517 static INLINE void var_add_spills_and_reloads(be_raext_env_t *raenv, int var_nr) {
518 be_var_info_t *vi = be_var_find(raenv->vars, var_nr);
519 ir_node *spill=NULL, *ctx, *irn;
521 const ir_edge_t *edge, *ne;
522 pset *spills = pset_new_ptr(4); /* the spills of this variable */
523 pset *reloads = pset_new_ptr(4); /* the reloads of this variable */
524 be_lv_t *lv = raenv->birg->lv;
525 be_dom_front_info_t *dom_front = raenv->birg->dom_front;
526 int new_size, n_spills, n_reloads;
528 assert(vi && "Variable nr does not exist!");
529 assert(pset_count(vi->values) && "There are no values associated to this variable");
531 /* the spill context is set to an arbitrary node of the phi-class,
532 * or the node itself if it is not member of a phi class
534 if (pset_count(vi->values) == 1)
535 ctx = get_first_non_phi(vi->values);
537 ctx = get_first_phi(vi->values);
539 DBG((raenv->dbg, LEVEL_2, "Spill context: %+F\n", ctx));
541 /* for each value of this variable insert the spills */
542 pset_foreach(vi->values, irn) {
548 /* all ordinary nodes must be spilled */
549 DBG((raenv->dbg, LEVEL_2, " spilling %+F\n", irn));
550 spill = be_spill(raenv->aenv, irn);
552 /* remember the spill */
553 pset_insert_ptr(spills, spill);
556 assert(spill && "There must be at least one non-phi-node");
558 mode = get_irn_mode(get_irn_n(spill, be_pos_Spill_val));
560 /* insert reloads and wire them arbitrary*/
561 pset_foreach(vi->values, irn) {
562 foreach_out_edge_safe(irn, edge, ne) {
563 ir_node *reload, *src = edge->src;
564 if (is_Phi(src) || be_is_Spill(src))
567 /* all real uses must be reloaded */
568 DBG((raenv->dbg, LEVEL_2, " reloading before %+F\n", src));
569 reload = be_reload(raenv->aenv, raenv->cls, edge->src, mode, spill);
570 set_irn_n(edge->src, edge->pos, reload);
572 /* remember the reload */
573 pset_insert_ptr(reloads, reload);
577 /* correct the reload->spill pointers... */
578 be_ssa_constr_set_ignore(dom_front, lv, spills, NULL);
581 /****** correct the variable <--> values mapping: ******
583 * - if we had a phi class it gets split into several new variables
584 * - all reloads are new variables
586 n_spills = pset_count(spills);
587 n_reloads = pset_count(reloads);
589 /* first make room for new pointers in the cls_var array */
590 new_size = raenv->n_cls_vars + n_reloads + ((n_spills>1) ? n_spills : 0);
591 raenv->cls_vars = realloc(raenv->cls_vars, (new_size) * sizeof(*raenv->cls_vars));
592 assert(raenv->cls_vars && "Out of mem!?");
594 /* if we had a real phi-class, we must... */
595 if (pset_count(spills) > 1) {
596 /* ...remove the old variable corresponding to the phi class */
597 vi->var_nr = SET_REMOVED;
599 /* ...add new vars for each non-phi-member */
600 pset_foreach(spills, irn) {
601 ir_node *spilled = get_irn_n(irn, be_pos_Spill_val);
602 raenv->cls_vars[raenv->n_cls_vars++] = be_var_add_value(raenv->vars, get_irn_node_nr(spilled), spilled);
606 /* add new variables for all reloads */
607 pset_foreach(reloads, irn) {
608 assert(get_irn_node_nr(irn) != 1089);
609 raenv->cls_vars[raenv->n_cls_vars++] = be_var_add_value(raenv->vars, get_irn_node_nr(irn), irn);
616 #define INVALID_FILE_FORMAT assert(0 && "Invalid file format.")
618 #define BUFCONV " %32s "
621 * Read in the actions performed by the external allocator.
622 * Apply these transformations to the irg.
623 * @return 1 if an allocation was read in. 0 otherwise.
625 static int read_and_apply_results(be_raext_env_t *raenv, char *filename) {
628 int is_allocation = 0;
630 if (!(f = fopen(filename, "rt"))) {
631 fprintf(stderr, "Could not open file %s for reading\n", filename);
636 /* read the action */
637 if (fscanf(f, BUFCONV, buf) != 1)
641 if (!strcmp(buf, "spills")) {
643 while (fscanf(f, " %d ", &var_nr) == 1)
644 var_add_spills_and_reloads(raenv, var_nr);
647 /* or do we allocate */
648 if (!strcmp(buf, "allocs")) {
652 while (fscanf(f, " %d %d ", &var_nr, ®_nr) == 2) {
654 pset *vals = be_get_var_values(raenv->vars, var_nr);
656 assert(vals && "Variable nr does not exist!");
657 pset_foreach(vals, irn)
658 arch_set_irn_register(raenv->aenv, irn, arch_register_for_index(raenv->cls, reg_nr));
668 return is_allocation;
671 static void check_allocation(be_raext_env_t *raenv) {
673 be_lv_t *lv = raenv->birg->lv;
675 for (i=0; i<raenv->n_cls_vars; ++i) {
676 be_var_info_t *vi1 = raenv->cls_vars[i];
678 if (vi1->var_nr == SET_REMOVED)
681 for (o=0; o<i; ++o) {
682 be_var_info_t *vi2 = raenv->cls_vars[o];
683 ir_node *irn1, *irn2;
685 if (vi2->var_nr == SET_REMOVED)
688 pset_foreach(vi1->values, irn1)
689 pset_foreach(vi2->values, irn2)
690 if (values_interfere(lv, irn1, irn2) && arch_get_irn_register(raenv->aenv, irn1) == arch_get_irn_register(raenv->aenv, irn2)) {
691 dump_ir_block_graph_sched(raenv->irg, "ERROR");
692 ir_fprintf(stdout, "SSA values %+F and %+F interfere. They belong to variable %d and %d respectively.\n", irn1, irn2, vi1->var_nr, vi2->var_nr);
693 assert(0 && "ERROR graph dumped");
699 /******************************************************************************
703 | |\/| |/ _` | | '_ \
704 | | | | (_| | | | | |
705 |_| |_|\__,_|_|_| |_|
706 *****************************************************************************/
709 * Default values for options
711 static char callee[128] = "\"E:/user/kimohoff/public/register allocator\"";
712 //static char callee[128] = "/ben/kimohoff/ipd-registerallocator/register_allocator";
716 * Allocate registers with an external program using a text-file interface.
718 * Do some computations (SSA-destruction and mapping of values--vars)
720 * Execute external program
721 * Read in results and apply them
724 static void be_ra_extern_main(be_irg_t *birg) {
725 be_main_env_t *env = birg->main_env;
726 ir_graph *irg = birg->irg;
728 be_raext_env_t raenv;
731 be_assure_dom_front(birg);
732 be_assure_liveness(birg);
737 raenv.aenv = env->arch_env;
738 FIRM_DBG_REGISTER(raenv.dbg, "firm.be.raextern");
740 /* Insert copies for constraints */
741 for(clsnr = 0, clss = arch_isa_get_n_reg_class(raenv.aenv->isa); clsnr < clss; ++clsnr) {
742 raenv.cls = arch_isa_get_reg_class(raenv.aenv->isa, clsnr);
743 handle_constraints(&raenv);
746 be_dump(irg, "-extern-constr", dump_ir_block_graph_sched);
748 /* SSA destruction respectively transformation into "Conventional SSA" */
749 raenv.vars = be_ssa_destr_simple(irg, env->arch_env);
750 be_dump(irg, "-extern-ssadestr", dump_ir_block_graph_sched);
753 /* For all register classes */
754 for(clsnr = 0, clss = arch_isa_get_n_reg_class(raenv.aenv->isa); clsnr < clss; ++clsnr) {
756 char out[256], in[256];
758 raenv.cls = arch_isa_get_reg_class(raenv.aenv->isa, clsnr);
760 extract_vars_of_cls(&raenv);
763 ir_snprintf(out, sizeof(out), "%F-%s-%d.ra", irg, raenv.cls->name, round);
764 ir_snprintf(in, sizeof(in), "%F-%s-%d.ra.res", irg, raenv.cls->name, round);
768 dump_to_file(&raenv, out);
769 execute(callee, out, in);
770 done = read_and_apply_results(&raenv, in);
771 be_abi_fix_stack_nodes(birg->abi);
773 ir_snprintf(in, sizeof(in), "-extern-%s-round-%d", raenv.cls->name, round);
774 be_dump(irg, in, dump_ir_block_graph_sched);
779 check_allocation(&raenv);
781 free(raenv.cls_vars);
784 be_dump(irg, "-extern-alloc", dump_ir_block_graph_sched);
787 free_ssa_destr_simple(raenv.vars);
789 be_liveness_invalidate(be_get_birg_liveness(birg));
792 /******************************************************************************
795 | | | |_ __ | |_ _ ___ _ __ ___
796 | | | | '_ \| __| |/ _ \| '_ \/ __|
797 | |__| | |_) | |_| | (_) | | | \__ \
798 \____/| .__/ \__|_|\___/|_| |_|___/
801 *****************************************************************************/
803 static const lc_opt_enum_func_ptr_items_t ssa_destr_items[] = {
804 { "simple", (int (*)(void)) be_ssa_destr_simple }, /* TODO make (void*) casts nicer */
808 static set* (*ssa_destr)(ir_graph*,const arch_env_t*) = be_ssa_destr_simple;
810 static lc_opt_enum_func_ptr_var_t ssa_destr_var = {
811 (int (**)(void)) &ssa_destr, ssa_destr_items
814 static const lc_opt_table_entry_t be_ra_extern_options[] = {
815 LC_OPT_ENT_ENUM_FUNC_PTR("ssa_destr", "SSA destruction flavor", &ssa_destr_var),
816 LC_OPT_ENT_STR("callee", "The external program to call", callee, sizeof(callee)),
820 static be_ra_t be_ra_external_allocator = {
824 void be_init_raextern(void) {
825 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
826 lc_opt_entry_t *blocksched_grp = lc_opt_get_grp(be_grp, "ra");
827 lc_opt_entry_t *ext_grp = lc_opt_get_grp(blocksched_grp, "ext");
829 lc_opt_add_table(ext_grp, be_ra_extern_options);
831 be_register_allocator("ext", &be_ra_external_allocator);
833 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_raextern);
835 #endif /* NOT_PORTED */