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