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