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