nsz Git - libfirm/blob - ir/be/beschednormal.c

   1 /*
   2  * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
   3  *
   4  * This file is part of libFirm.
   5  *
   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.
  10  *
  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.
  14  *
  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
  17  * PURPOSE.
  18  */
  19
  20 /**
  21  * @brief   Use the strong normal form theorem (though it does not hold)
  22  * @author  Christoph Mallon
  23  */
  24 #include "config.h"
  25
  26 #include <stdlib.h>
  27
  28 #include "besched.h"
  29 #include "belistsched.h"
  30 #include "belive_t.h"
  31 #include "beutil.h"
  32 #include "heights.h"
  33 #include "irgwalk.h"
  34 #include "benode.h"
  35 #include "bemodule.h"
  36 #include "util.h"
  37 #include "array_t.h"
  38
  39 // XXX there is no one time init for schedulers
  40 //#define NORMAL_DBG
  41 #include "irprintf.h"
  42
  43 /** An instance of the normal scheduler. */
  44 typedef struct instance_t {
  45         ir_graph*      irg;          /**< the IR graph of this instance */
  46         struct obstack obst;         /**< obstack for temporary data */
  47         ir_node*       curr_list;    /**< current block schedule list */
  48 } instance_t;
  49
  50 static int must_be_scheduled(const ir_node* const irn)
  51 {
  52         return !is_Proj(irn) && !is_Sync(irn);
  53 }
  54
  55
  56 static ir_node *normal_select(void *block_env, ir_nodeset_t *ready_set)
  57 {
  58         instance_t* inst = (instance_t*)block_env;
  59         ir_node*    irn;
  60         ir_node*    next;
  61         ir_node*    last = NULL;
  62         ir_nodeset_iterator_t iter;
  63
  64         for (irn = inst->curr_list; irn != NULL; last = irn, irn = next) {
  65                 next = (ir_node*)get_irn_link(irn);
  66                 if (ir_nodeset_contains(ready_set, irn)) {
  67 #if defined NORMAL_DBG
  68                         ir_fprintf(stderr, "scheduling %+F\n", irn);
  69 #endif
  70                         if (last == NULL)
  71                                 inst->curr_list = next;
  72                         else
  73                                 set_irn_link(last, next);
  74                         return irn;
  75                 }
  76         }
  77
  78         ir_nodeset_iterator_init(&iter, ready_set);
  79         irn = ir_nodeset_iterator_next(&iter);
  80         return irn;
  81 }
  82
  83
  84 typedef struct irn_cost_pair {
  85         ir_node* irn;
  86         int      cost;
  87 } irn_cost_pair;
  88
  89 static int cost_cmp(const void* a, const void* b)
  90 {
  91         const irn_cost_pair* const a1 = (const irn_cost_pair*)a;
  92         const irn_cost_pair* const b1 = (const irn_cost_pair*)b;
  93         int ret = b1->cost - a1->cost;
  94         if (ret == 0)
  95                 ret = (int)get_irn_idx(a1->irn) - (int)get_irn_idx(b1->irn);
  96 #if defined NORMAL_DBG
  97         ir_fprintf(stderr, "cost %+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
  98 #endif
  99         return ret;
 100 }
 101
 102
 103 typedef struct flag_and_cost {
 104         int no_root;
 105         irn_cost_pair costs[];
 106 } flag_and_cost;
 107
 108 #define get_irn_fc(irn)     ((flag_and_cost*)get_irn_link(irn))
 109 #define set_irn_fc(irn, fc) set_irn_link(irn, fc)
 110
 111
 112 static int count_result(const ir_node* irn)
 113 {
 114         const ir_mode* mode = get_irn_mode(irn);
 115
 116         if (mode == mode_M || mode == mode_X)
 117                 return 0;
 118
 119         if (mode == mode_T)
 120                 return 1;
 121
 122         if (arch_get_irn_register_req(irn)->type & arch_register_req_type_ignore)
 123                 return 0;
 124
 125         return 1;
 126 }
 127
 128
 129 /* TODO high cost for store trees
 130  */
 131
 132 static int normal_tree_cost(ir_node* irn, instance_t *inst)
 133 {
 134         flag_and_cost* fc;
 135         int            arity;
 136         ir_node*       last;
 137         int            n_res;
 138         int            cost;
 139         int            n_op_res = 0;
 140         int            i;
 141
 142         if (be_is_Keep(irn))
 143                 return 0;
 144
 145         if (is_Proj(irn)) {
 146                 return normal_tree_cost(get_Proj_pred(irn), inst);
 147         }
 148
 149         arity = get_irn_arity(irn);
 150         fc    = get_irn_fc(irn);
 151
 152         if (fc == NULL) {
 153                 irn_cost_pair* costs;
 154                 ir_node*       block = get_nodes_block(irn);
 155
 156                 fc = OALLOCF(&inst->obst, flag_and_cost, costs, arity);
 157                 fc->no_root = 0;
 158                 costs = fc->costs;
 159
 160                 for (i = 0; i < arity; ++i) {
 161                         ir_node* pred = get_irn_n(irn, i);
 162
 163                         if (is_Phi(irn) || get_irn_mode(pred) == mode_M || is_Block(pred)) {
 164                                 cost = 0;
 165                         } else if (get_nodes_block(pred) != block) {
 166                                 cost = 1;
 167                         } else {
 168                                 flag_and_cost* pred_fc;
 169                                 ir_node*       real_pred;
 170
 171                                 cost = normal_tree_cost(pred, inst);
 172                                 if (!arch_irn_is_ignore(pred)) {
 173                                         real_pred = (is_Proj(pred) ? get_Proj_pred(pred) : pred);
 174                                         pred_fc = get_irn_fc(real_pred);
 175                                         pred_fc->no_root = 1;
 176 #if defined NORMAL_DBG
 177                                         ir_fprintf(stderr, "%+F says that %+F is no root\n", irn, real_pred);
 178 #endif
 179                                 }
 180                         }
 181
 182                         costs[i].irn  = pred;
 183                         costs[i].cost = cost;
 184                 }
 185
 186                 qsort(costs, arity, sizeof(*costs), cost_cmp);
 187                 set_irn_link(irn, fc);
 188         }
 189
 190         cost = 0;
 191         last = 0;
 192         for (i = 0; i < arity; ++i) {
 193                 ir_node* op = fc->costs[i].irn;
 194                 ir_mode* mode;
 195                 if (op == last)
 196                         continue;
 197                 mode = get_irn_mode(op);
 198                 if (mode == mode_M)
 199                         continue;
 200                 if (arch_get_irn_flags(op) & arch_irn_flags_not_scheduled)
 201                         continue;
 202                 if (mode != mode_T && arch_irn_is_ignore(op))
 203                         continue;
 204                 cost = MAX(fc->costs[i].cost + n_op_res, cost);
 205                 last = op;
 206                 ++n_op_res;
 207         }
 208         n_res = count_result(irn);
 209         cost = MAX(n_res, cost);
 210
 211 #if defined NORMAL_DBG
 212         ir_fprintf(stderr, "reguse of %+F is %d\n", irn, cost);
 213 #endif
 214
 215         return cost;
 216 }
 217
 218
 219 static void normal_cost_walker(ir_node* irn, void* env)
 220 {
 221         instance_t *inst = (instance_t*)env;
 222
 223 #if defined NORMAL_DBG
 224         ir_fprintf(stderr, "cost walking node %+F\n", irn);
 225 #endif
 226         if (is_Block(irn)) return;
 227         if (!must_be_scheduled(irn)) return;
 228         normal_tree_cost(irn, inst);
 229 }
 230
 231
 232 static void collect_roots(ir_node* irn, void* env)
 233 {
 234         int is_root;
 235
 236         (void)env;
 237
 238         if (is_Block(irn)) return;
 239         if (!must_be_scheduled(irn)) return;
 240
 241         is_root = be_is_Keep(irn) || !get_irn_fc(irn)->no_root;
 242
 243 #if defined NORMAL_DBG
 244         ir_fprintf(stderr, "%+F is %sroot\n", irn, is_root ? "" : "no ");
 245 #endif
 246
 247         if (is_root) {
 248                 ir_node* block = get_nodes_block(irn);
 249                 ir_node** roots = (ir_node**)get_irn_link(block);
 250                 if (roots == NULL) {
 251                         roots = NEW_ARR_F(ir_node*, 0);
 252                 }
 253                 ARR_APP1(ir_node*, roots, irn);
 254                 set_irn_link(block, roots);
 255         }
 256 }
 257
 258
 259 static ir_node** sched_node(ir_node** sched, ir_node* irn)
 260 {
 261         if (irn_visited_else_mark(irn)) return sched;
 262         if (is_End(irn))                return sched;
 263
 264         if (!is_Phi(irn) && !be_is_Keep(irn)) {
 265                 ir_node*       block = get_nodes_block(irn);
 266                 int            arity = get_irn_arity(irn);
 267                 flag_and_cost* fc    = get_irn_fc(irn);
 268                 irn_cost_pair* irns  = fc->costs;
 269                 int            i;
 270
 271                 for (i = 0; i < arity; ++i) {
 272                         ir_node* pred = irns[i].irn;
 273                         if (get_nodes_block(pred) != block) continue;
 274                         if (get_irn_mode(pred) == mode_M) continue;
 275                         if (is_Proj(pred)) pred = get_Proj_pred(pred);
 276                         sched = sched_node(sched, pred);
 277                 }
 278         }
 279
 280         ARR_APP1(ir_node*, sched, irn);
 281         return sched;
 282 }
 283
 284
 285 static int root_cmp(const void* a, const void* b)
 286 {
 287         const irn_cost_pair* const a1 = (const irn_cost_pair*)a;
 288         const irn_cost_pair* const b1 = (const irn_cost_pair*)b;
 289         int ret;
 290         if (is_irn_forking(a1->irn) && !is_irn_forking(b1->irn)) {
 291                 ret = 1;
 292         } else if (is_irn_forking(b1->irn) && !is_irn_forking(a1->irn)) {
 293                 ret = -1;
 294         } else {
 295                 ret = b1->cost - a1->cost;
 296                 if (ret == 0) {
 297                         /* place live-out nodes later */
 298                         ret = (count_result(a1->irn) != 0) - (count_result(b1->irn) != 0);
 299                         if (ret == 0) {
 300                                 /* compare node idx */
 301                                 ret = get_irn_idx(a1->irn) - get_irn_idx(b1->irn);
 302                         }
 303                 }
 304         }
 305 #if defined NORMAL_DBG
 306         ir_fprintf(stderr, "root %+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
 307 #endif
 308         return ret;
 309 }
 310
 311
 312 static void normal_sched_block(ir_node* block, void* env)
 313 {
 314         ir_node**      roots = (ir_node**)get_irn_link(block);
 315         ir_heights_t*  heights = (ir_heights_t*)env;
 316         int            root_count;
 317         irn_cost_pair* root_costs;
 318         int i;
 319         ir_node**      sched;
 320
 321 #if defined NORMAL_DBG
 322         ir_fprintf(stderr, "sched walking block %+F\n", block);
 323 #endif
 324
 325         if (roots == NULL) {
 326 #if defined NORMAL_DBG
 327                 fprintf(stderr, "has no roots\n");
 328 #endif
 329                 return;
 330         }
 331
 332         root_count = ARR_LEN(roots);
 333         NEW_ARR_A(irn_cost_pair, root_costs, root_count);
 334         for (i = 0; i < root_count; ++i) {
 335                 root_costs[i].irn  = roots[i];
 336                 root_costs[i].cost = get_irn_height(heights, roots[i]);
 337 #if defined NORMAL_DBG
 338                 ir_fprintf(stderr, "height of %+F is %u\n", roots[i], root_costs[i].cost);
 339 #endif
 340         }
 341         qsort(root_costs, root_count, sizeof(*root_costs), root_cmp);
 342 #if defined NORMAL_DBG
 343         {
 344                 int n = root_count;
 345                 int i;
 346
 347                 ir_fprintf(stderr, "Root Scheduling of %+F:\n", block);
 348                 for (i = 0; i < n; ++i) {
 349                         ir_fprintf(stderr, "  %+F\n", root_costs[i].irn);
 350                 }
 351                 fprintf(stderr, "\n");
 352         }
 353 #endif
 354
 355         sched = NEW_ARR_F(ir_node*, 0);
 356         for (i = 0; i < root_count; ++i) {
 357                 ir_node* irn = root_costs[i].irn;
 358                 assert(must_be_scheduled(irn));
 359                 sched = sched_node(sched, irn);
 360         }
 361         set_irn_link(block, sched);
 362         DEL_ARR_F(roots);
 363
 364 #if defined NORMAL_DBG
 365         {
 366                 int n = ARR_LEN(sched);
 367                 int i;
 368
 369                 ir_fprintf(stderr, "Scheduling of %+F:\n", block);
 370                 for (i = 0; i < n; ++i) {
 371                         ir_fprintf(stderr, "  %+F\n", sched[i]);
 372                 }
 373                 fprintf(stderr, "\n");
 374         }
 375 #endif
 376 }
 377
 378
 379 static void *normal_init_graph(ir_graph *irg)
 380 {
 381         instance_t   *inst = XMALLOC(instance_t);
 382         ir_heights_t *heights;
 383
 384         be_clear_links(irg);
 385
 386         obstack_init(&inst->obst);
 387         inst->irg         = irg;
 388
 389         heights = heights_new(irg);
 390
 391         ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
 392         irg_walk_graph(irg, normal_cost_walker,  NULL, inst);
 393         irg_walk_graph(irg, collect_roots, NULL, NULL);
 394         inc_irg_visited(irg);
 395         ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
 396         irg_block_walk_graph(irg, normal_sched_block, NULL, heights);
 397         ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
 398
 399         heights_free(heights);
 400
 401         return inst;
 402 }
 403
 404 static void *normal_init_block(void *graph_env, ir_node *block)
 405 {
 406         instance_t* inst  = (instance_t*)graph_env;
 407         ir_node**   sched = (ir_node**)get_irn_link(block);
 408         ir_node*    first = NULL;
 409         int         i;
 410
 411         /* turn into a list, so we can easily remove nodes.
 412            The link field is used anyway. */
 413         for (i = ARR_LEN(sched) - 1; i >= 0; --i) {
 414                 ir_node* irn = sched[i];
 415                 if (!is_cfop(irn)) {
 416                         set_irn_link(irn, first);
 417                         first = irn;
 418                 }
 419         }
 420         /* note: we can free sched here, there should be no attempt to schedule
 421            a block twice */
 422         DEL_ARR_F(sched);
 423         set_irn_link(block, sched);
 424         inst->curr_list = first;
 425         return inst;
 426 }
 427
 428 static void normal_finish_graph(void *env)
 429 {
 430         instance_t *inst = (instance_t*)env;
 431
 432         /* block uses the link field to store the schedule */
 433         ir_free_resources(inst->irg, IR_RESOURCE_IRN_LINK);
 434         obstack_free(&inst->obst, NULL);
 435         xfree(inst);
 436 }
 437
 438 static void sched_normal(ir_graph *irg)
 439 {
 440         static const list_sched_selector_t normal_selector = {
 441                 normal_init_graph,
 442                 normal_init_block,
 443                 normal_select,
 444                 NULL,              /* node_ready */
 445                 NULL,              /* node_selected */
 446                 NULL,              /* finish_block */
 447                 normal_finish_graph
 448         };
 449         be_list_sched_graph(irg, &normal_selector);
 450 }
 451
 452 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_sched_normal)
 453 void be_init_sched_normal(void)
 454 {
 455         be_register_scheduler("normal", sched_normal);
 456 }