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 #include "irprintf.h"
  44
  45
  46 static int must_be_scheduled(const ir_node* const irn)
  47 {
  48         return !is_Proj(irn) && !is_Sync(irn);
  49 }
  50
  51
  52 static const arch_env_t *cur_arch_env;
  53
  54
  55 static ir_node *normal_select(void *block_env, ir_nodeset_t *ready_set,
  56                               ir_nodeset_t *live_set)
  57 {
  58         ir_nodeset_iterator_t iter;
  59         ir_node*  block;
  60         ir_node*  irn;
  61         ir_node** sched;
  62         int sched_count;
  63
  64         (void)block_env;
  65         (void)live_set;
  66
  67         ir_nodeset_iterator_init(&iter, ready_set);
  68         irn = ir_nodeset_iterator_next(&iter);
  69         block = get_nodes_block(irn);
  70         sched = get_irn_link(block);
  71         sched_count = ARR_LEN(sched);
  72         for (; sched_count-- != 0; ++sched) {
  73                 ir_node* irn = *sched;
  74                 if (ir_nodeset_contains(ready_set, irn) &&
  75                                 !arch_irn_class_is(cur_arch_env, irn, branch)) {
  76 #if defined NORMAL_DBG
  77                         ir_fprintf(stderr, "scheduling %+F\n", irn);
  78 #endif
  79                         return irn;
  80                 }
  81         }
  82
  83         return irn;
  84 }
  85
  86
  87 typedef struct irn_cost_pair {
  88         ir_node* irn;
  89         int      cost;
  90 } irn_cost_pair;
  91
  92
  93 static int cost_cmp(const void* a, const void* b)
  94 {
  95         const irn_cost_pair* const a1 = a;
  96         const irn_cost_pair* const b1 = b;
  97         int ret = b1->cost - a1->cost;
  98         if (ret == 0)
  99                 ret = (int)get_irn_idx(a1->irn) - (int)get_irn_idx(b1->irn);
 100 #if defined NORMAL_DBG
 101         ir_fprintf(stderr, "cost %+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
 102 #endif
 103         return ret;
 104 }
 105
 106
 107 typedef struct flag_and_cost {
 108         int no_root;
 109         irn_cost_pair costs[];
 110 } flag_and_cost;
 111
 112
 113 static int count_result(const ir_node* irn)
 114 {
 115         const ir_mode* mode = get_irn_mode(irn);
 116         return
 117                 mode != mode_M &&
 118                 mode != mode_X &&
 119                 !arch_irn_is(cur_arch_env, irn, ignore);
 120 }
 121
 122
 123 /* TODO high cost for store trees
 124  */
 125
 126
 127 static int normal_tree_cost(ir_node* irn)
 128 {
 129         flag_and_cost* fc    = get_irn_link(irn);
 130         ir_node*       block = get_nodes_block(irn);
 131         int            arity = get_irn_arity(irn);
 132         ir_node*       last;
 133         int            n_res;
 134         int            cost;
 135         int            n_op_res = 0;
 136         int            i;
 137
 138         if (be_is_Keep(irn))
 139                 return 0;
 140
 141         if (is_Proj(irn)) {
 142                 return normal_tree_cost(get_Proj_pred(irn));
 143         }
 144
 145         if (fc == NULL) {
 146                 irn_cost_pair* costs;
 147                 int            i;
 148
 149                 fc = malloc(sizeof(*fc) + sizeof(*fc->costs) * arity);
 150                 fc->no_root = 0;
 151                 costs = fc->costs;
 152
 153                 for (i = 0; i < arity; ++i) {
 154                         ir_node* pred = get_irn_n(irn, i);
 155                         int cost;
 156
 157                         if (is_Phi(irn) || get_irn_mode(pred) == mode_M || is_Block(pred)) {
 158                                 cost = 0;
 159                         } else if (get_nodes_block(pred) != block) {
 160                                 cost = 1;
 161                         } else {
 162                                 flag_and_cost* pred_fc;
 163                                 ir_node*       real_pred;
 164
 165                                 cost = normal_tree_cost(pred);
 166                                 if (be_is_Barrier(pred)) cost = 1; // XXX hack: the barrier causes all users to have a reguse of #regs
 167                                 if (!arch_irn_is(cur_arch_env, pred, ignore)) {
 168                                         real_pred = (is_Proj(pred) ? get_Proj_pred(pred) : pred);
 169                                         pred_fc = get_irn_link(real_pred);
 170                                         pred_fc->no_root = 1;
 171 #if defined NORMAL_DBG
 172                                         ir_fprintf(stderr, "%+F says that %+F is no root\n", irn, real_pred);
 173 #endif
 174                                 }
 175                         }
 176
 177                         costs[i].irn  = pred;
 178                         costs[i].cost = cost;
 179                 }
 180
 181                 qsort(costs, arity, sizeof(*costs), cost_cmp);
 182                 set_irn_link(irn, fc);
 183         }
 184
 185         cost = 0;
 186         last = 0;
 187         for (i = 0; i < arity; ++i) {
 188                 ir_node* op = fc->costs[i].irn;
 189                 if (op == last)                            continue;
 190                 if (get_irn_mode(op) == mode_M)            continue;
 191                 if (arch_irn_is(cur_arch_env, op, ignore)) continue;
 192                 cost = MAX(fc->costs[i].cost + n_op_res, cost);
 193                 last = op;
 194                 ++n_op_res;
 195         }
 196         n_res = count_result(irn);
 197         cost = MAX(n_res, cost);
 198
 199 #if defined NORMAL_DBG
 200         ir_fprintf(stderr, "reguse of %+F is %d\n", irn, cost);
 201 #endif
 202
 203         return cost;
 204 }
 205
 206
 207 static void normal_cost_walker(ir_node* irn, void* env)
 208 {
 209         (void)env;
 210
 211 #if defined NORMAL_DBG
 212         ir_fprintf(stderr, "cost walking node %+F\n", irn);
 213 #endif
 214         if (is_Block(irn)) return;
 215         if (!must_be_scheduled(irn)) return;
 216         normal_tree_cost(irn);
 217 }
 218
 219
 220 static void collect_roots(ir_node* irn, void* env)
 221 {
 222         int is_root;
 223
 224         (void)env;
 225
 226         if (is_Block(irn)) return;
 227         if (!must_be_scheduled(irn)) return;
 228
 229         is_root = be_is_Keep(irn) || !((flag_and_cost*)get_irn_link(irn))->no_root;
 230
 231 #if defined NORMAL_DBG
 232         ir_fprintf(stderr, "%+F is %sroot\n", irn, is_root ? "" : "no ");
 233 #endif
 234
 235         if (is_root) {
 236                 ir_node* block = get_nodes_block(irn);
 237                 ir_node** roots = get_irn_link(block);
 238                 if (roots == NULL) {
 239                         roots = NEW_ARR_F(ir_node*, 0);
 240                 }
 241                 ARR_APP1(ir_node*, roots, irn);
 242                 set_irn_link(block, roots);
 243         }
 244 }
 245
 246
 247 static ir_node** sched_node(ir_node** sched, ir_node* irn)
 248 {
 249         ir_node*       block = get_nodes_block(irn);
 250         flag_and_cost* fc    = get_irn_link(irn);
 251         irn_cost_pair* irns  = fc->costs;
 252         int            arity = get_irn_arity(irn);
 253         int            i;
 254
 255         if (irn_visited(irn)) return sched;
 256         if (is_End(irn))      return sched;
 257
 258         if (!is_Phi(irn) && !be_is_Keep(irn)) {
 259                 for (i = 0; i < arity; ++i) {
 260                         ir_node* pred = irns[i].irn;
 261                         if (get_nodes_block(pred) != block) continue;
 262                         if (get_irn_mode(pred) == mode_M) continue;
 263                         if (is_Proj(pred)) pred = get_Proj_pred(pred);
 264                         sched = sched_node(sched, pred);
 265                 }
 266         }
 267
 268         mark_irn_visited(irn);
 269         ARR_APP1(ir_node*, sched, irn);
 270         return sched;
 271 }
 272
 273
 274 static int root_cmp(const void* a, const void* b)
 275 {
 276         const irn_cost_pair* const a1 = a;
 277         const irn_cost_pair* const b1 = b;
 278         int ret;
 279         if (is_irn_forking(a1->irn)) {
 280                 ret = 1;
 281         } else if (is_irn_forking(b1->irn)) {
 282                 ret = -1;
 283         } else {
 284                 ret = b1->cost - a1->cost;
 285                 if (ret == 0) {
 286                         /* place live-out nodes later */
 287                         ret = (count_result(a1->irn) != 0) - (count_result(b1->irn) != 0);
 288                 }
 289         }
 290 #if defined NORMAL_DBG
 291         ir_fprintf(stderr, "root %+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
 292 #endif
 293         return ret;
 294 }
 295
 296
 297 static void normal_sched_block(ir_node* block, void* env)
 298 {
 299         heights_t*     heights = env;
 300         ir_node**      roots   = get_irn_link(block);
 301         int            root_count;
 302         irn_cost_pair* root_costs;
 303         int i;
 304         ir_node**      sched;
 305
 306 #if defined NORMAL_DBG
 307         ir_fprintf(stderr, "sched walking block %+F\n", block);
 308 #endif
 309
 310         if (roots == NULL) {
 311 #if defined NORMAL_DBG
 312                 fprintf(stderr, "has no roots\n");
 313 #endif
 314                 return;
 315         }
 316
 317         root_count = ARR_LEN(roots);
 318         NEW_ARR_A(irn_cost_pair, root_costs, root_count);
 319         for (i = 0; i < root_count; ++i) {
 320                 root_costs[i].irn  = roots[i];
 321                 root_costs[i].cost = get_irn_height(heights, roots[i]);
 322 #if defined NORMAL_DBG
 323                 ir_fprintf(stderr, "height of %+F is %u\n", roots[i], root_costs[i].cost);
 324 #endif
 325         }
 326         qsort(root_costs, root_count, sizeof(*root_costs), root_cmp);
 327 #if defined NORMAL_DBG
 328         {
 329                 int n = root_count;
 330                 int i;
 331
 332                 ir_fprintf(stderr, "Root Scheduling of %+F:\n", block);
 333                 for (i = 0; i < n; ++i) {
 334                         ir_fprintf(stderr, "  %+F\n", root_costs[i].irn);
 335                 }
 336                 fprintf(stderr, "\n");
 337         }
 338 #endif
 339
 340         sched = NEW_ARR_F(ir_node*, 0);
 341         for (i = 0; i < root_count; ++i) {
 342                 ir_node* irn = root_costs[i].irn;
 343                 assert(must_be_scheduled(irn));
 344                 sched = sched_node(sched, irn);
 345         }
 346         set_irn_link(block, sched);
 347         DEL_ARR_F(roots);
 348
 349 #if defined NORMAL_DBG
 350         {
 351                 int n = ARR_LEN(sched);
 352                 int i;
 353
 354                 ir_fprintf(stderr, "Scheduling of %+F:\n", block);
 355                 for (i = 0; i < n; ++i) {
 356                         ir_fprintf(stderr, "  %+F\n", sched[i]);
 357                 }
 358                 fprintf(stderr, "\n");
 359         }
 360 #endif
 361 }
 362
 363
 364 static void *normal_init_graph(const list_sched_selector_t *vtab,
 365                                const be_irg_t *birg)
 366 {
 367         ir_graph  *irg = be_get_birg_irg(birg);
 368         heights_t *heights;
 369
 370         (void)vtab;
 371
 372         cur_arch_env = be_get_birg_arch_env(birg);
 373
 374         be_clear_links(irg);
 375
 376         heights = heights_new(irg);
 377
 378         irg_walk_graph(irg, normal_cost_walker,  NULL, NULL);
 379         irg_walk_graph(irg, collect_roots, NULL, NULL);
 380         inc_irg_visited(irg);
 381         irg_block_walk_graph(irg, normal_sched_block, NULL, heights);
 382
 383         heights_free(heights);
 384
 385         return NULL;
 386 }
 387
 388
 389 static void *normal_init_block(void *graph_env, ir_node *block)
 390 {
 391         (void)graph_env;
 392         (void)block;
 393
 394         return NULL;
 395 }
 396
 397
 398 const list_sched_selector_t normal_selector = {
 399         normal_init_graph,
 400         normal_init_block,
 401         normal_select,
 402         NULL,              /* to_appear_in_schedule */
 403         NULL,              /* node_ready */
 404         NULL,              /* node_selected */
 405         NULL,              /* exectime */
 406         NULL,              /* latency */
 407         NULL,              /* finish_block */
 408         NULL               /* finish_graph */
 409 };