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 #include "array_t.h"
  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 ir_node *normal_select(void *block_env, ir_nodeset_t *ready_set,
  53                               ir_nodeset_t *live_set)
  54 {
  55         ir_nodeset_iterator_t iter;
  56         ir_node*  block;
  57         ir_node*  irn;
  58         ir_node** sched;
  59         int sched_count;
  60
  61         (void)block_env;
  62         (void)live_set;
  63
  64         ir_nodeset_iterator_init(&iter, ready_set);
  65         irn = ir_nodeset_iterator_next(&iter);
  66         block = get_nodes_block(irn);
  67         sched = get_irn_link(block);
  68         sched_count = ARR_LEN(sched);
  69         for (; sched_count-- != 0; ++sched) {
  70                 ir_node* irn = *sched;
  71                 if (ir_nodeset_contains(ready_set, irn) &&
  72                                 !arch_irn_class_is(irn, branch)) {
  73 #if defined NORMAL_DBG
  74                         ir_fprintf(stderr, "scheduling %+F\n", irn);
  75 #endif
  76                         return irn;
  77                 }
  78         }
  79
  80         return irn;
  81 }
  82
  83
  84 typedef struct irn_cost_pair {
  85         ir_node* irn;
  86         int      cost;
  87 } irn_cost_pair;
  88
  89
  90 static int cost_cmp(const void* a, const void* b)
  91 {
  92         const irn_cost_pair* const a1 = a;
  93         const irn_cost_pair* const b1 = 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
 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(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         ir_node*       last;
 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(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         last = 0;
 184         for (i = 0; i < arity; ++i) {
 185                 ir_node* op = fc->costs[i].irn;
 186                 if (op == last)                 continue;
 187                 if (get_irn_mode(op) == mode_M) continue;
 188                 if (arch_irn_is(op, ignore))    continue;
 189                 cost = MAX(fc->costs[i].cost + n_op_res, cost);
 190                 last = op;
 191                 ++n_op_res;
 192         }
 193         n_res = count_result(irn);
 194         cost = MAX(n_res, cost);
 195
 196 #if defined NORMAL_DBG
 197         ir_fprintf(stderr, "reguse of %+F is %d\n", irn, cost);
 198 #endif
 199
 200         return cost;
 201 }
 202
 203
 204 static void normal_cost_walker(ir_node* irn, void* env)
 205 {
 206         (void)env;
 207
 208 #if defined NORMAL_DBG
 209         ir_fprintf(stderr, "cost walking node %+F\n", irn);
 210 #endif
 211         if (is_Block(irn)) return;
 212         if (!must_be_scheduled(irn)) return;
 213         normal_tree_cost(irn);
 214 }
 215
 216
 217 static void collect_roots(ir_node* irn, void* env)
 218 {
 219         int is_root;
 220
 221         (void)env;
 222
 223         if (is_Block(irn)) return;
 224         if (!must_be_scheduled(irn)) return;
 225
 226         is_root = be_is_Keep(irn) || !((flag_and_cost*)get_irn_link(irn))->no_root;
 227
 228 #if defined NORMAL_DBG
 229         ir_fprintf(stderr, "%+F is %sroot\n", irn, is_root ? "" : "no ");
 230 #endif
 231
 232         if (is_root) {
 233                 ir_node* block = get_nodes_block(irn);
 234                 ir_node** roots = get_irn_link(block);
 235                 if (roots == NULL) {
 236                         roots = NEW_ARR_F(ir_node*, 0);
 237                 }
 238                 ARR_APP1(ir_node*, roots, irn);
 239                 set_irn_link(block, roots);
 240         }
 241 }
 242
 243
 244 static ir_node** sched_node(ir_node** sched, ir_node* irn)
 245 {
 246         ir_node*       block = get_nodes_block(irn);
 247         flag_and_cost* fc    = get_irn_link(irn);
 248         irn_cost_pair* irns  = fc->costs;
 249         int            arity = get_irn_arity(irn);
 250         int            i;
 251
 252         if (irn_visited_else_mark(irn)) return sched;
 253         if (is_End(irn))                return sched;
 254
 255         if (!is_Phi(irn) && !be_is_Keep(irn)) {
 256                 for (i = 0; i < arity; ++i) {
 257                         ir_node* pred = irns[i].irn;
 258                         if (get_nodes_block(pred) != block) continue;
 259                         if (get_irn_mode(pred) == mode_M) continue;
 260                         if (is_Proj(pred)) pred = get_Proj_pred(pred);
 261                         sched = sched_node(sched, pred);
 262                 }
 263         }
 264
 265         ARR_APP1(ir_node*, sched, irn);
 266         return sched;
 267 }
 268
 269
 270 static int root_cmp(const void* a, const void* b)
 271 {
 272         const irn_cost_pair* const a1 = a;
 273         const irn_cost_pair* const b1 = b;
 274         int ret;
 275         if (is_irn_forking(a1->irn)) {
 276                 ret = 1;
 277         } else if (is_irn_forking(b1->irn)) {
 278                 ret = -1;
 279         } else {
 280                 ret = b1->cost - a1->cost;
 281                 if (ret == 0) {
 282                         /* place live-out nodes later */
 283                         ret = (count_result(a1->irn) != 0) - (count_result(b1->irn) != 0);
 284                 }
 285         }
 286 #if defined NORMAL_DBG
 287         ir_fprintf(stderr, "root %+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
 288 #endif
 289         return ret;
 290 }
 291
 292
 293 static void normal_sched_block(ir_node* block, void* env)
 294 {
 295         heights_t*     heights = env;
 296         ir_node**      roots   = get_irn_link(block);
 297         int            root_count;
 298         irn_cost_pair* root_costs;
 299         int i;
 300         ir_node**      sched;
 301
 302 #if defined NORMAL_DBG
 303         ir_fprintf(stderr, "sched walking block %+F\n", block);
 304 #endif
 305
 306         if (roots == NULL) {
 307 #if defined NORMAL_DBG
 308                 fprintf(stderr, "has no roots\n");
 309 #endif
 310                 return;
 311         }
 312
 313         root_count = ARR_LEN(roots);
 314         NEW_ARR_A(irn_cost_pair, root_costs, root_count);
 315         for (i = 0; i < root_count; ++i) {
 316                 root_costs[i].irn  = roots[i];
 317                 root_costs[i].cost = get_irn_height(heights, roots[i]);
 318 #if defined NORMAL_DBG
 319                 ir_fprintf(stderr, "height of %+F is %u\n", roots[i], root_costs[i].cost);
 320 #endif
 321         }
 322         qsort(root_costs, root_count, sizeof(*root_costs), root_cmp);
 323 #if defined NORMAL_DBG
 324         {
 325                 int n = root_count;
 326                 int i;
 327
 328                 ir_fprintf(stderr, "Root Scheduling of %+F:\n", block);
 329                 for (i = 0; i < n; ++i) {
 330                         ir_fprintf(stderr, "  %+F\n", root_costs[i].irn);
 331                 }
 332                 fprintf(stderr, "\n");
 333         }
 334 #endif
 335
 336         sched = NEW_ARR_F(ir_node*, 0);
 337         for (i = 0; i < root_count; ++i) {
 338                 ir_node* irn = root_costs[i].irn;
 339                 assert(must_be_scheduled(irn));
 340                 sched = sched_node(sched, irn);
 341         }
 342         set_irn_link(block, sched);
 343         DEL_ARR_F(roots);
 344
 345 #if defined NORMAL_DBG
 346         {
 347                 int n = ARR_LEN(sched);
 348                 int i;
 349
 350                 ir_fprintf(stderr, "Scheduling of %+F:\n", block);
 351                 for (i = 0; i < n; ++i) {
 352                         ir_fprintf(stderr, "  %+F\n", sched[i]);
 353                 }
 354                 fprintf(stderr, "\n");
 355         }
 356 #endif
 357 }
 358
 359
 360 static void *normal_init_graph(const list_sched_selector_t *vtab,
 361                                const be_irg_t *birg)
 362 {
 363         ir_graph  *irg = be_get_birg_irg(birg);
 364         heights_t *heights;
 365
 366         (void)vtab;
 367
 368         be_clear_links(irg);
 369
 370         heights = heights_new(irg);
 371
 372         irg_walk_graph(irg, normal_cost_walker,  NULL, NULL);
 373         irg_walk_graph(irg, collect_roots, NULL, NULL);
 374         inc_irg_visited(irg);
 375         irg_block_walk_graph(irg, normal_sched_block, NULL, heights);
 376
 377         heights_free(heights);
 378
 379         return NULL;
 380 }
 381
 382
 383 static void *normal_init_block(void *graph_env, ir_node *block)
 384 {
 385         (void)graph_env;
 386         (void)block;
 387
 388         return NULL;
 389 }
 390
 391
 392 const list_sched_selector_t normal_selector = {
 393         normal_init_graph,
 394         normal_init_block,
 395         normal_select,
 396         NULL,              /* to_appear_in_schedule */
 397         NULL,              /* node_ready */
 398         NULL,              /* node_selected */
 399         NULL,              /* exectime */
 400         NULL,              /* latency */
 401         NULL,              /* finish_block */
 402         NULL               /* finish_graph */
 403 };