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 #ifdef HAVE_CONFIG_H
  26 #include "config.h"
  27 #endif
  28
  29 #include <stdlib.h>
  30
  31 #include "besched_t.h"
  32 #include "belistsched.h"
  33 #include "belive_t.h"
  34 #include "beutil.h"
  35 #include "height.h"
  36 #include "irtools.h"
  37 #include "irgwalk.h"
  38 #include "benode_t.h"
  39
  40
  41 // XXX there is no one time init for schedulers
  42 //#define NORMAL_DBG
  43
  44
  45 static int must_be_scheduled(const ir_node* const irn)
  46 {
  47         return !is_Proj(irn) && !is_Sync(irn);
  48 }
  49
  50
  51 static const arch_env_t *cur_arch_env;
  52
  53
  54 static ir_node *normal_select(void *block_env, ir_nodeset_t *ready_set,
  55                               ir_nodeset_t *live_set)
  56 {
  57         ir_nodeset_iterator_t iter;
  58         ir_node*  block;
  59         ir_node*  irn;
  60         ir_node** sched;
  61         int sched_count;
  62
  63         (void)block_env;
  64         (void)live_set;
  65
  66         ir_nodeset_iterator_init(&iter, ready_set);
  67         irn = ir_nodeset_iterator_next(&iter);
  68         block = get_nodes_block(irn);
  69         sched = get_irn_link(block);
  70         sched_count = ARR_LEN(sched);
  71         for (; sched_count-- != 0; ++sched) {
  72                 ir_node* irn = *sched;
  73                 if (ir_nodeset_contains(ready_set, irn) &&
  74                                 !arch_irn_class_is(cur_arch_env, irn, branch)) {
  75 #if defined NORMAL_DBG
  76                         ir_fprintf(stderr, "scheduling %+F\n", irn);
  77 #endif
  78                         return irn;
  79                 }
  80         }
  81
  82         return irn;
  83 }
  84
  85
  86 typedef struct irn_cost_pair {
  87         ir_node* irn;
  88         int      cost;
  89 } irn_cost_pair;
  90
  91
  92 static int cost_cmp(const void* a, const void* b)
  93 {
  94         const irn_cost_pair* const a1 = a;
  95         const irn_cost_pair* const b1 = b;
  96         int ret = b1->cost - a1->cost;
  97 #if defined NORMAL_DBG
  98         ir_fprintf(stderr, "%+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
 110 static int count_result(const ir_node* irn)
 111 {
 112         const ir_mode* mode = get_irn_mode(irn);
 113         return
 114                 mode != mode_M &&
 115                 mode != mode_X &&
 116                 !arch_irn_is(cur_arch_env, irn, ignore);
 117 }
 118
 119
 120 /* TODO high cost for store trees
 121  */
 122
 123
 124 static int normal_tree_cost(ir_node* irn)
 125 {
 126         flag_and_cost* fc    = get_irn_link(irn);
 127         ir_node*       block = get_nodes_block(irn);
 128         int            arity = get_irn_arity(irn);
 129         int            n_res;
 130         int            cost;
 131         int            n_op_res = 0;
 132         int            i;
 133
 134         if (be_is_Keep(irn))
 135                 return 0;
 136
 137         if (is_Proj(irn)) {
 138                 return normal_tree_cost(get_Proj_pred(irn));
 139         }
 140
 141         if (fc == NULL) {
 142                 irn_cost_pair* costs;
 143                 int            i;
 144
 145                 fc = malloc(sizeof(*fc) + sizeof(*fc->costs) * arity);
 146                 fc->no_root = 0;
 147                 costs = fc->costs;
 148
 149                 for (i = 0; i < arity; ++i) {
 150                         ir_node* pred = get_irn_n(irn, i);
 151                         int cost;
 152
 153                         if (is_Phi(irn) || get_irn_mode(pred) == mode_M || is_Block(pred)) {
 154                                 cost = 0;
 155                         } else if (get_nodes_block(pred) != block) {
 156                                 cost = 1;
 157                         } else {
 158                                 flag_and_cost* pred_fc;
 159                                 ir_node*       real_pred;
 160
 161                                 cost = normal_tree_cost(pred);
 162                                 if (be_is_Barrier(pred)) cost = 1; // XXX hack: the barrier causes all users to have a reguse of #regs
 163                                 if (!arch_irn_is(cur_arch_env, pred, ignore)) {
 164                                         real_pred = (is_Proj(pred) ? get_Proj_pred(pred) : pred);
 165                                         pred_fc = get_irn_link(real_pred);
 166                                         pred_fc->no_root = 1;
 167 #if defined NORMAL_DBG
 168                                         ir_fprintf(stderr, "%+F says that %+F is no root\n", irn, real_pred);
 169 #endif
 170                                 }
 171                         }
 172
 173                         costs[i].irn  = pred;
 174                         costs[i].cost = cost;
 175                 }
 176
 177                 qsort(costs, arity, sizeof(*costs), cost_cmp);
 178                 set_irn_link(irn, fc);
 179         }
 180
 181         cost = 0;
 182         for (i = 0; i < arity; ++i) {
 183                 if (get_irn_mode(fc->costs[i].irn) == mode_M) continue;
 184                 if (arch_irn_is(cur_arch_env, fc->costs[i].irn, ignore)) continue;
 185                 cost = MAX(fc->costs[i].cost + n_op_res, cost);
 186                 ++n_op_res;
 187         }
 188         n_res = count_result(irn);
 189         cost = MAX(n_res, cost);
 190
 191 #if defined NORMAL_DBG
 192         ir_fprintf(stderr, "reguse of %+F is %d\n", irn, cost);
 193 #endif
 194
 195         return cost;
 196 }
 197
 198
 199 static void normal_cost_walker(ir_node* irn, void* env)
 200 {
 201         (void)env;
 202
 203 #if defined NORMAL_DBG
 204         ir_fprintf(stderr, "cost walking node %+F\n", irn);
 205 #endif
 206         if (is_Block(irn)) return;
 207         if (!must_be_scheduled(irn)) return;
 208         normal_tree_cost(irn);
 209 }
 210
 211
 212 static void collect_roots(ir_node* irn, void* env)
 213 {
 214         int is_root;
 215
 216         (void)env;
 217
 218         if (is_Block(irn)) return;
 219         if (!must_be_scheduled(irn)) return;
 220
 221         is_root = be_is_Keep(irn) || !((flag_and_cost*)get_irn_link(irn))->no_root;
 222
 223 #if defined NORMAL_DBG
 224         ir_fprintf(stderr, "%+F is %sroot\n", irn, is_root ? "" : "no ");
 225 #endif
 226
 227         if (is_root) {
 228                 ir_node* block = get_nodes_block(irn);
 229                 ir_node** roots = get_irn_link(block);
 230                 if (roots == NULL) {
 231                         roots = NEW_ARR_F(ir_node*, 0);
 232                 }
 233                 ARR_APP1(ir_node*, roots, irn);
 234                 set_irn_link(block, roots);
 235         }
 236 }
 237
 238
 239 static ir_node** sched_node(ir_node** sched, ir_node* irn)
 240 {
 241         ir_node*       block = get_nodes_block(irn);
 242         flag_and_cost* fc    = get_irn_link(irn);
 243         irn_cost_pair* irns  = fc->costs;
 244         int            arity = get_irn_arity(irn);
 245         int            i;
 246
 247         if (irn_visited(irn)) return sched;
 248         if (is_End(irn))      return sched;
 249
 250         if (!is_Phi(irn) && !be_is_Keep(irn)) {
 251                 for (i = 0; i < arity; ++i) {
 252                         ir_node* pred = irns[i].irn;
 253                         if (get_nodes_block(pred) != block) continue;
 254                         if (get_irn_mode(pred) == mode_M) continue;
 255                         if (is_Proj(pred)) pred = get_Proj_pred(pred);
 256                         sched = sched_node(sched, pred);
 257                 }
 258         }
 259
 260         mark_irn_visited(irn);
 261         ARR_APP1(ir_node*, sched, irn);
 262         return sched;
 263 }
 264
 265
 266 static int root_cmp(const void* a, const void* b)
 267 {
 268         const irn_cost_pair* const a1 = a;
 269         const irn_cost_pair* const b1 = b;
 270         int ret;
 271         if (is_irn_forking(a1->irn)) {
 272                 ret = 1;
 273         } else if (is_irn_forking(b1->irn)) {
 274                 ret = -1;
 275         } else {
 276                 ret = b1->cost - a1->cost;
 277                 if (ret == 0) {
 278                         /* place live-out nodes later */
 279                         ret = (count_result(a1->irn) != 0) - (count_result(b1->irn) != 0);
 280                 }
 281         }
 282 #if defined NORMAL_DBG
 283         ir_fprintf(stderr, "%+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
 284 #endif
 285         return ret;
 286 }
 287
 288
 289 static void normal_sched_block(ir_node* block, void* env)
 290 {
 291         heights_t*     heights = env;
 292         ir_node**      roots   = get_irn_link(block);
 293         int            root_count;
 294         irn_cost_pair* root_costs;
 295         int i;
 296         ir_node**      sched;
 297
 298 #if defined NORMAL_DBG
 299         ir_fprintf(stderr, "sched walking block %+F\n", block);
 300 #endif
 301
 302         if (roots == NULL) {
 303 #if defined NORMAL_DBG
 304                 fprintf(stderr, "has no roots\n");
 305 #endif
 306                 return;
 307         }
 308
 309         root_count = ARR_LEN(roots);
 310         NEW_ARR_A(irn_cost_pair, root_costs, root_count);
 311         for (i = 0; i < root_count; ++i) {
 312                 root_costs[i].irn  = roots[i];
 313                 root_costs[i].cost = get_irn_height(heights, roots[i]);
 314 #if defined NORMAL_DBG
 315                 ir_fprintf(stderr, "height of %+F is %u\n", roots[i], root_costs[i].cost);
 316 #endif
 317         }
 318         qsort(root_costs, root_count, sizeof(*root_costs), root_cmp);
 319 #if defined NORMAL_DBG
 320         {
 321                 int n = root_count;
 322                 int i;
 323
 324                 ir_fprintf(stderr, "Root Scheduling of %+F:\n", block);
 325                 for (i = 0; i < n; ++i) {
 326                         ir_fprintf(stderr, "  %+F\n", root_costs[i].irn);
 327                 }
 328                 fprintf(stderr, "\n");
 329         }
 330 #endif
 331
 332         sched = NEW_ARR_F(ir_node*, 0);
 333         for (i = 0; i < root_count; ++i) {
 334                 ir_node* irn = root_costs[i].irn;
 335                 assert(must_be_scheduled(irn));
 336                 sched = sched_node(sched, irn);
 337         }
 338         set_irn_link(block, sched);
 339         DEL_ARR_F(roots);
 340
 341 #if defined NORMAL_DBG
 342         {
 343                 int n = ARR_LEN(sched);
 344                 int i;
 345
 346                 ir_fprintf(stderr, "Scheduling of %+F:\n", block);
 347                 for (i = 0; i < n; ++i) {
 348                         ir_fprintf(stderr, "  %+F\n", sched[i]);
 349                 }
 350                 fprintf(stderr, "\n");
 351         }
 352 #endif
 353 }
 354
 355
 356 static void *normal_init_graph(const list_sched_selector_t *vtab,
 357                                const be_irg_t *birg)
 358 {
 359         ir_graph  *irg = be_get_birg_irg(birg);
 360         heights_t *heights;
 361
 362         (void)vtab;
 363
 364         cur_arch_env = be_get_birg_arch_env(birg);
 365
 366         be_clear_links(irg);
 367
 368         heights = heights_new(irg);
 369
 370         irg_walk_graph(irg, normal_cost_walker,  NULL, NULL);
 371         irg_walk_graph(irg, collect_roots, NULL, NULL);
 372         inc_irg_visited(irg);
 373         irg_block_walk_graph(irg, normal_sched_block, NULL, heights);
 374
 375         heights_free(heights);
 376
 377         return NULL;
 378 }
 379
 380
 381 static void *normal_init_block(void *graph_env, ir_node *block)
 382 {
 383         (void)graph_env;
 384         (void)block;
 385
 386         return NULL;
 387 }
 388
 389
 390 const list_sched_selector_t normal_selector = {
 391         normal_init_graph,
 392         normal_init_block,
 393         normal_select,
 394         NULL,              /* to_appear_in_schedule */
 395         NULL,              /* node_ready */
 396         NULL,              /* node_selected */
 397         NULL,              /* exectime */
 398         NULL,              /* latency */
 399         NULL,              /* finish_block */
 400         NULL               /* finish_graph */
 401 };