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 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 .
81 #include <libcore/lc_opts.h>
82 #include <libcore/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);
431 if (arch_register_req_is(req, should_be_same)) {
432 ir_node *other = get_irn_n(skip_Proj(irn), req->other_same);
433 if(arch_irn_is(raenv->aenv, other, ignore)) {
434 vi2 = be_get_var_info(other);
436 fprintf(raenv->f, "(%d, %d, %d)\n", vi1->var_nr, vi2->var_nr, get_affinity_weight(irn));
443 static void dump_affinities(be_raext_env_t *raenv) {
444 fprintf(raenv->f, "\naffinities {\n");
445 irg_walk_graph(raenv->irg, NULL, dump_affinities_walker, raenv);
446 fprintf(raenv->f, "}\n");
450 * Dump all information needed by the external
451 * register allocator to a single file.
453 static void dump_to_file(be_raext_env_t *raenv, char *filename) {
456 if (!(f = fopen(filename, "wt"))) {
457 fprintf(stderr, "Could not open file %s for writing\n", filename);
463 /* dump register info */
464 fprintf(f, "regs %d\n", arch_register_class_n_regs(raenv->cls));
466 /* dump the interference graph */
468 dump_interferences(raenv);
469 dump_affinities(raenv);
474 /******************************************************************************
477 | |__ __ _____ ___ _ _| |_ ___
478 | __| \ \/ / _ \/ __| | | | __/ _ \
479 | |____ > < __/ (__| |_| | || __/
480 |______/_/\_\___|\___|\__,_|\__\___|
481 *****************************************************************************/
484 * Execute the external register allocator specified in the
485 * firm-option firm.be.ra.ext.callee
487 static void execute(char *prog_to_call, char *out_file, char *result_file) {
491 snprintf(cmd_line, sizeof(cmd_line), "%s -i %s -o %s", prog_to_call, out_file, result_file);
492 cmd_line[sizeof(cmd_line) - 1] = '\0';
494 ret_status = system(cmd_line);
495 assert(ret_status != -1 && "Invokation of external register allocator failed");
496 assert(ret_status == 0 && "External register allocator is unhappy with sth.");
499 /******************************************************************************
502 / \ _ __ _ __ | |_ _ | |__) |___ ___ _ _| | |_
503 / /\ \ | '_ \| '_ \| | | | | | _ // _ \/ __| | | | | __|
504 / ____ \| |_) | |_) | | |_| | | | \ \ __/\__ \ |_| | | |_
505 /_/ \_\ .__/| .__/|_|\__, | |_| \_\___||___/\__,_|_|\__|
508 *****************************************************************************/
511 * Spill a variable and add reloads before all uses.
513 static INLINE void var_add_spills_and_reloads(be_raext_env_t *raenv, int var_nr) {
514 be_var_info_t *vi = be_var_find(raenv->vars, var_nr);
515 ir_node *spill=NULL, *ctx, *irn;
517 const ir_edge_t *edge, *ne;
518 pset *spills = pset_new_ptr(4); /* the spills of this variable */
519 pset *reloads = pset_new_ptr(4); /* the reloads of this variable */
520 be_lv_t *lv = raenv->birg->lv;
521 be_dom_front_info_t *dom_front = raenv->birg->dom_front;
522 int new_size, n_spills, n_reloads;
524 assert(vi && "Variable nr does not exist!");
525 assert(pset_count(vi->values) && "There are no values associated to this variable");
527 /* the spill context is set to an arbitrary node of the phi-class,
528 * or the node itself if it is not member of a phi class
530 if (pset_count(vi->values) == 1)
531 ctx = get_first_non_phi(vi->values);
533 ctx = get_first_phi(vi->values);
535 DBG((raenv->dbg, LEVEL_2, "Spill context: %+F\n", ctx));
537 /* for each value of this variable insert the spills */
538 pset_foreach(vi->values, irn) {
544 /* all ordinary nodes must be spilled */
545 DBG((raenv->dbg, LEVEL_2, " spilling %+F\n", irn));
546 spill = be_spill(raenv->aenv, irn);
548 /* remember the spill */
549 pset_insert_ptr(spills, spill);
552 assert(spill && "There must be at least one non-phi-node");
554 mode = get_irn_mode(get_irn_n(spill, be_pos_Spill_val));
556 /* insert reloads and wire them arbitrary*/
557 pset_foreach(vi->values, irn) {
558 foreach_out_edge_safe(irn, edge, ne) {
559 ir_node *reload, *src = edge->src;
560 if (is_Phi(src) || be_is_Spill(src))
563 /* all real uses must be reloaded */
564 DBG((raenv->dbg, LEVEL_2, " reloading before %+F\n", src));
565 reload = be_reload(raenv->aenv, raenv->cls, edge->src, mode, spill);
566 set_irn_n(edge->src, edge->pos, reload);
568 /* remember the reload */
569 pset_insert_ptr(reloads, reload);
573 /* correct the reload->spill pointers... */
574 be_ssa_constr_set_ignore(dom_front, lv, spills, NULL);
577 /****** correct the variable <--> values mapping: ******
579 * - if we had a phi class it gets split into several new variables
580 * - all reloads are new variables
582 n_spills = pset_count(spills);
583 n_reloads = pset_count(reloads);
585 /* first make room for new pointers in the cls_var array */
586 new_size = raenv->n_cls_vars + n_reloads + ((n_spills>1) ? n_spills : 0);
587 raenv->cls_vars = realloc(raenv->cls_vars, (new_size) * sizeof(*raenv->cls_vars));
588 assert(raenv->cls_vars && "Out of mem!?");
590 /* if we had a real phi-class, we must... */
591 if (pset_count(spills) > 1) {
592 /* ...remove the old variable corresponding to the phi class */
593 vi->var_nr = SET_REMOVED;
595 /* ...add new vars for each non-phi-member */
596 pset_foreach(spills, irn) {
597 ir_node *spilled = get_irn_n(irn, be_pos_Spill_val);
598 raenv->cls_vars[raenv->n_cls_vars++] = be_var_add_value(raenv->vars, get_irn_node_nr(spilled), spilled);
602 /* add new variables for all reloads */
603 pset_foreach(reloads, irn) {
604 assert(get_irn_node_nr(irn) != 1089);
605 raenv->cls_vars[raenv->n_cls_vars++] = be_var_add_value(raenv->vars, get_irn_node_nr(irn), irn);
612 #define INVALID_FILE_FORMAT assert(0 && "Invalid file format.")
614 #define BUFCONV " %32s "
617 * Read in the actions performed by the external allocator.
618 * Apply these transformations to the irg.
619 * @return 1 if an allocation was read in. 0 otherwise.
621 static int read_and_apply_results(be_raext_env_t *raenv, char *filename) {
624 int is_allocation = 0;
626 if (!(f = fopen(filename, "rt"))) {
627 fprintf(stderr, "Could not open file %s for reading\n", filename);
633 /* read the action */
634 if (fscanf(f, BUFCONV, buf) != 1)
638 if (!strcmp(buf, "spills")) {
640 while (fscanf(f, " %d ", &var_nr) == 1)
641 var_add_spills_and_reloads(raenv, var_nr);
644 /* or do we allocate */
645 if (!strcmp(buf, "allocs")) {
649 while (fscanf(f, " %d %d ", &var_nr, ®_nr) == 2) {
651 pset *vals = be_get_var_values(raenv->vars, var_nr);
653 assert(vals && "Variable nr does not exist!");
654 pset_foreach(vals, irn)
655 arch_set_irn_register(raenv->aenv, irn, arch_register_for_index(raenv->cls, reg_nr));
665 return is_allocation;
668 static void check_allocation(be_raext_env_t *raenv) {
670 be_lv_t *lv = raenv->birg->lv;
672 for (i=0; i<raenv->n_cls_vars; ++i) {
673 be_var_info_t *vi1 = raenv->cls_vars[i];
675 if (vi1->var_nr == SET_REMOVED)
678 for (o=0; o<i; ++o) {
679 be_var_info_t *vi2 = raenv->cls_vars[o];
680 ir_node *irn1, *irn2;
682 if (vi2->var_nr == SET_REMOVED)
685 pset_foreach(vi1->values, irn1)
686 pset_foreach(vi2->values, irn2)
687 if (values_interfere(lv, irn1, irn2) && arch_get_irn_register(raenv->aenv, irn1) == arch_get_irn_register(raenv->aenv, irn2)) {
688 dump_ir_block_graph_sched(raenv->irg, "ERROR");
689 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);
690 assert(0 && "ERROR graph dumped");
696 /******************************************************************************
700 | |\/| |/ _` | | '_ \
701 | | | | (_| | | | | |
702 |_| |_|\__,_|_|_| |_|
703 *****************************************************************************/
706 * Default values for options
708 static char callee[128] = "\"E:/user/kimohoff/public/register allocator\"";
709 //static char callee[128] = "/ben/kimohoff/ipd-registerallocator/register_allocator";
713 * Allocate registers with an external program using a text-file interface.
715 * Do some computations (SSA-destruction and mapping of values--vars)
717 * Execute external program
718 * Read in results and apply them
721 static void be_ra_extern_main(be_irg_t *birg) {
722 be_main_env_t *env = birg->main_env;
723 ir_graph *irg = birg->irg;
725 be_raext_env_t raenv;
728 be_assure_dom_front(birg);
729 be_assure_liveness(birg);
734 raenv.aenv = env->arch_env;
735 FIRM_DBG_REGISTER(raenv.dbg, "firm.be.raextern");
737 /* Insert copies for constraints */
738 for(clsnr = 0, clss = arch_isa_get_n_reg_class(raenv.aenv->isa); clsnr < clss; ++clsnr) {
739 raenv.cls = arch_isa_get_reg_class(raenv.aenv->isa, clsnr);
740 handle_constraints(&raenv);
743 be_dump(irg, "-extern-constr", dump_ir_block_graph_sched);
745 /* SSA destruction respectively transformation into "Conventional SSA" */
746 raenv.vars = be_ssa_destr_simple(irg, env->arch_env);
747 be_dump(irg, "-extern-ssadestr", dump_ir_block_graph_sched);
750 /* For all register classes */
751 for(clsnr = 0, clss = arch_isa_get_n_reg_class(raenv.aenv->isa); clsnr < clss; ++clsnr) {
753 char out[256], in[256];
755 raenv.cls = arch_isa_get_reg_class(raenv.aenv->isa, clsnr);
757 extract_vars_of_cls(&raenv);
760 ir_snprintf(out, sizeof(out), "%F-%s-%d.ra", irg, raenv.cls->name, round);
761 ir_snprintf(in, sizeof(in), "%F-%s-%d.ra.res", irg, raenv.cls->name, round);
765 dump_to_file(&raenv, out);
766 execute(callee, out, in);
767 done = read_and_apply_results(&raenv, in);
768 be_abi_fix_stack_nodes(birg->abi);
770 ir_snprintf(in, sizeof(in), "-extern-%s-round-%d", raenv.cls->name, round);
771 be_dump(irg, in, dump_ir_block_graph_sched);
776 check_allocation(&raenv);
778 free(raenv.cls_vars);
781 be_dump(irg, "-extern-alloc", dump_ir_block_graph_sched);
784 free_ssa_destr_simple(raenv.vars);
786 be_invalidate_liveness(birg);
789 /******************************************************************************
792 | | | |_ __ | |_ _ ___ _ __ ___
793 | | | | '_ \| __| |/ _ \| '_ \/ __|
794 | |__| | |_) | |_| | (_) | | | \__ \
795 \____/| .__/ \__|_|\___/|_| |_|___/
798 *****************************************************************************/
800 static const lc_opt_enum_func_ptr_items_t ssa_destr_items[] = {
801 { "simple", (int (*)(void)) be_ssa_destr_simple }, /* TODO make (void*) casts nicer */
805 static set* (*ssa_destr)(ir_graph*,const arch_env_t*) = be_ssa_destr_simple;
807 static lc_opt_enum_func_ptr_var_t ssa_destr_var = {
808 (int (**)(void)) &ssa_destr, ssa_destr_items
811 static const lc_opt_table_entry_t be_ra_extern_options[] = {
812 LC_OPT_ENT_ENUM_FUNC_PTR("ssa_destr", "SSA destruction flavor", &ssa_destr_var),
813 LC_OPT_ENT_STR("callee", "The external program to call", callee, sizeof(callee)),
817 static be_ra_t be_ra_external_allocator = {
821 void be_init_raextern(void) {
822 lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
823 lc_opt_entry_t *blocksched_grp = lc_opt_get_grp(be_grp, "ra");
824 lc_opt_entry_t *ext_grp = lc_opt_get_grp(blocksched_grp, "ext");
826 lc_opt_add_table(ext_grp, be_ra_extern_options);
828 be_register_allocator("ext", &be_ra_external_allocator);
830 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_raextern);
832 #endif /* NOT_PORTED */