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  */
  24 #include "config.h"
  25
  26 #include <stdlib.h>
  27
  28 #include "besched.h"
  29 #include "belistsched.h"
  30 #include "belive_t.h"
  31 #include "beutil.h"
  32 #include "heights.h"
  33 #include "irgwalk.h"
  34 #include "benode.h"
  35 #include "bemodule.h"
  36 #include "util.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 /** An instance of the normal scheduler. */
  44 typedef struct instance_t {
  45         ir_graph*      irg;          /**< the IR graph of this instance */
  46         struct obstack obst;         /**< obstack for temporary data */
  47         ir_node*       curr_list;    /**< current block schedule list */
  48 } instance_t;
  49
  50 static int must_be_scheduled(const ir_node* const irn)
  51 {
  52         return !is_Proj(irn) && !arch_irn_is(irn, not_scheduled);
  53 }
  54
  55
  56 static ir_node *normal_select(void *block_env, ir_nodeset_t *ready_set)
  57 {
  58         instance_t* inst = (instance_t*)block_env;
  59         ir_node*    irn;
  60         ir_node*    next;
  61         ir_node*    last = NULL;
  62
  63         for (irn = inst->curr_list; irn != NULL; last = irn, irn = next) {
  64                 next = (ir_node*)get_irn_link(irn);
  65                 if (ir_nodeset_contains(ready_set, irn)) {
  66 #if defined NORMAL_DBG
  67                         ir_fprintf(stderr, "scheduling %+F\n", irn);
  68 #endif
  69                         if (last == NULL)
  70                                 inst->curr_list = next;
  71                         else
  72                                 set_irn_link(last, next);
  73                         return irn;
  74                 }
  75         }
  76
  77         return ir_nodeset_first(ready_set);
  78 }
  79
  80
  81 typedef struct irn_cost_pair {
  82         ir_node* irn;
  83         int      cost;
  84 } irn_cost_pair;
  85
  86 static int cost_cmp(const void* a, const void* b)
  87 {
  88         const irn_cost_pair* const a1 = (const irn_cost_pair*)a;
  89         const irn_cost_pair* const b1 = (const irn_cost_pair*)b;
  90         int ret = b1->cost - a1->cost;
  91         if (ret == 0)
  92                 ret = (int)get_irn_idx(a1->irn) - (int)get_irn_idx(b1->irn);
  93 #if defined NORMAL_DBG
  94         ir_fprintf(stderr, "cost %+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
  95 #endif
  96         return ret;
  97 }
  98
  99
 100 typedef struct flag_and_cost {
 101         int no_root;
 102         irn_cost_pair costs[];
 103 } flag_and_cost;
 104
 105 #define get_irn_fc(irn)     ((flag_and_cost*)get_irn_link(irn))
 106 #define set_irn_fc(irn, fc) set_irn_link(irn, fc)
 107
 108
 109 static int count_result(const ir_node* irn)
 110 {
 111         const ir_mode* mode = get_irn_mode(irn);
 112
 113         if (mode == mode_M || mode == mode_X)
 114                 return 0;
 115
 116         if (mode == mode_T)
 117                 return 1;
 118
 119         arch_register_req_t const *const req = arch_get_irn_register_req(irn);
 120         if (arch_register_req_is(req, ignore))
 121                 return 0;
 122
 123         return 1;
 124 }
 125
 126
 127 /* TODO high cost for store trees
 128  */
 129
 130 static int normal_tree_cost(ir_node* irn, instance_t *inst)
 131 {
 132         flag_and_cost* fc;
 133         int            arity;
 134         ir_node*       last;
 135         int            n_res;
 136         int            cost;
 137         int            n_op_res = 0;
 138         int            i;
 139
 140         if (be_is_Keep(irn))
 141                 return 0;
 142
 143         if (is_Proj(irn)) {
 144                 return normal_tree_cost(get_Proj_pred(irn), inst);
 145         }
 146
 147         arity = get_irn_arity(irn);
 148         fc    = get_irn_fc(irn);
 149
 150         if (fc == NULL) {
 151                 irn_cost_pair* costs;
 152                 ir_node*       block = get_nodes_block(irn);
 153
 154                 fc = OALLOCF(&inst->obst, flag_and_cost, costs, arity);
 155                 fc->no_root = 0;
 156                 costs = fc->costs;
 157
 158                 for (i = 0; i < arity; ++i) {
 159                         ir_node* pred = get_irn_n(irn, i);
 160
 161                         if (is_Phi(irn) || get_irn_mode(pred) == mode_M) {
 162                                 cost = 0;
 163                         } else if (get_nodes_block(pred) != block) {
 164                                 cost = 1;
 165                         } else {
 166                                 flag_and_cost* pred_fc;
 167                                 ir_node*       real_pred;
 168
 169                                 cost = normal_tree_cost(pred, inst);
 170                                 if (!arch_irn_is_ignore(pred)) {
 171                                         real_pred = (is_Proj(pred) ? get_Proj_pred(pred) : pred);
 172                                         pred_fc = get_irn_fc(real_pred);
 173                                         pred_fc->no_root = 1;
 174 #if defined NORMAL_DBG
 175                                         ir_fprintf(stderr, "%+F says that %+F is no root\n", irn, real_pred);
 176 #endif
 177                                 }
 178                         }
 179
 180                         costs[i].irn  = pred;
 181                         costs[i].cost = cost;
 182                 }
 183
 184                 qsort(costs, arity, sizeof(*costs), cost_cmp);
 185                 set_irn_link(irn, fc);
 186         }
 187
 188         cost = 0;
 189         last = 0;
 190         for (i = 0; i < arity; ++i) {
 191                 ir_node* op = fc->costs[i].irn;
 192                 ir_mode* mode;
 193                 if (op == last)
 194                         continue;
 195                 mode = get_irn_mode(op);
 196                 if (mode == mode_M)
 197                         continue;
 198                 if (arch_irn_is_ignore(op))
 199                         continue;
 200                 cost = MAX(fc->costs[i].cost + n_op_res, cost);
 201                 last = op;
 202                 ++n_op_res;
 203         }
 204         n_res = count_result(irn);
 205         cost = MAX(n_res, cost);
 206
 207 #if defined NORMAL_DBG
 208         ir_fprintf(stderr, "reguse of %+F is %d\n", irn, cost);
 209 #endif
 210
 211         return cost;
 212 }
 213
 214
 215 static void normal_cost_walker(ir_node* irn, void* env)
 216 {
 217         instance_t *inst = (instance_t*)env;
 218
 219 #if defined NORMAL_DBG
 220         ir_fprintf(stderr, "cost walking node %+F\n", irn);
 221 #endif
 222         if (is_Block(irn)) {
 223                 ir_node **const roots = NEW_ARR_F(ir_node*, 0);
 224                 set_irn_link(irn, roots);
 225                 return;
 226         }
 227         if (!must_be_scheduled(irn)) return;
 228         normal_tree_cost(irn, inst);
 229 }
 230
 231
 232 static void collect_roots(ir_node* irn, void* env)
 233 {
 234         int is_root;
 235
 236         (void)env;
 237
 238         if (!must_be_scheduled(irn)) return;
 239
 240         is_root = be_is_Keep(irn) || !get_irn_fc(irn)->no_root;
 241
 242 #if defined NORMAL_DBG
 243         ir_fprintf(stderr, "%+F is %sroot\n", irn, is_root ? "" : "no ");
 244 #endif
 245
 246         if (is_root) {
 247                 ir_node* block = get_nodes_block(irn);
 248                 ir_node** roots = (ir_node**)get_irn_link(block);
 249                 ARR_APP1(ir_node*, roots, irn);
 250                 set_irn_link(block, roots);
 251         }
 252 }
 253
 254
 255 static ir_node** sched_node(ir_node** sched, ir_node* irn)
 256 {
 257         if (irn_visited_else_mark(irn)) return sched;
 258
 259         if (!is_Phi(irn) && !be_is_Keep(irn)) {
 260                 ir_node*       block = get_nodes_block(irn);
 261                 int            arity = get_irn_arity(irn);
 262                 flag_and_cost* fc    = get_irn_fc(irn);
 263                 irn_cost_pair* irns  = fc->costs;
 264                 int            i;
 265
 266                 for (i = 0; i < arity; ++i) {
 267                         ir_node* pred = irns[i].irn;
 268                         if (get_nodes_block(pred) != block) continue;
 269                         if (get_irn_mode(pred) == mode_M) continue;
 270                         if (is_Proj(pred)) pred = get_Proj_pred(pred);
 271                         sched = sched_node(sched, pred);
 272                 }
 273         }
 274
 275         ARR_APP1(ir_node*, sched, irn);
 276         return sched;
 277 }
 278
 279
 280 static int root_cmp(const void* a, const void* b)
 281 {
 282         const irn_cost_pair* const a1 = (const irn_cost_pair*)a;
 283         const irn_cost_pair* const b1 = (const irn_cost_pair*)b;
 284         int ret;
 285         if (is_irn_forking(a1->irn) && !is_irn_forking(b1->irn)) {
 286                 ret = 1;
 287         } else if (is_irn_forking(b1->irn) && !is_irn_forking(a1->irn)) {
 288                 ret = -1;
 289         } else {
 290                 ret = b1->cost - a1->cost;
 291                 if (ret == 0) {
 292                         /* place live-out nodes later */
 293                         ret = (count_result(a1->irn) != 0) - (count_result(b1->irn) != 0);
 294                         if (ret == 0) {
 295                                 /* compare node idx */
 296                                 ret = get_irn_idx(a1->irn) - get_irn_idx(b1->irn);
 297                         }
 298                 }
 299         }
 300 #if defined NORMAL_DBG
 301         ir_fprintf(stderr, "root %+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
 302 #endif
 303         return ret;
 304 }
 305
 306
 307 static void normal_sched_block(ir_node* block, void* env)
 308 {
 309         ir_node**      roots = (ir_node**)get_irn_link(block);
 310         ir_heights_t*  heights = (ir_heights_t*)env;
 311         irn_cost_pair* root_costs;
 312         int i;
 313         ir_node**      sched;
 314
 315 #if defined NORMAL_DBG
 316         ir_fprintf(stderr, "sched walking block %+F\n", block);
 317 #endif
 318
 319         int const root_count = ARR_LEN(roots);
 320         if (root_count == 0) {
 321 #if defined NORMAL_DBG
 322                 fprintf(stderr, "has no roots\n");
 323 #endif
 324                 return;
 325         }
 326
 327         NEW_ARR_A(irn_cost_pair, root_costs, root_count);
 328         for (i = 0; i < root_count; ++i) {
 329                 root_costs[i].irn  = roots[i];
 330                 root_costs[i].cost = get_irn_height(heights, roots[i]);
 331 #if defined NORMAL_DBG
 332                 ir_fprintf(stderr, "height of %+F is %u\n", roots[i], root_costs[i].cost);
 333 #endif
 334         }
 335         qsort(root_costs, root_count, sizeof(*root_costs), root_cmp);
 336 #if defined NORMAL_DBG
 337         {
 338                 int n = root_count;
 339                 int i;
 340
 341                 ir_fprintf(stderr, "Root Scheduling of %+F:\n", block);
 342                 for (i = 0; i < n; ++i) {
 343                         ir_fprintf(stderr, "  %+F\n", root_costs[i].irn);
 344                 }
 345                 fprintf(stderr, "\n");
 346         }
 347 #endif
 348
 349         sched = NEW_ARR_F(ir_node*, 0);
 350         for (i = 0; i < root_count; ++i) {
 351                 ir_node* irn = root_costs[i].irn;
 352                 assert(must_be_scheduled(irn));
 353                 sched = sched_node(sched, irn);
 354         }
 355         set_irn_link(block, sched);
 356         DEL_ARR_F(roots);
 357
 358 #if defined NORMAL_DBG
 359         {
 360                 int n = ARR_LEN(sched);
 361                 int i;
 362
 363                 ir_fprintf(stderr, "Scheduling of %+F:\n", block);
 364                 for (i = 0; i < n; ++i) {
 365                         ir_fprintf(stderr, "  %+F\n", sched[i]);
 366                 }
 367                 fprintf(stderr, "\n");
 368         }
 369 #endif
 370 }
 371
 372
 373 static void *normal_init_graph(ir_graph *irg)
 374 {
 375         instance_t   *inst = XMALLOC(instance_t);
 376         ir_heights_t *heights;
 377
 378         be_clear_links(irg);
 379
 380         obstack_init(&inst->obst);
 381         inst->irg         = irg;
 382
 383         heights = heights_new(irg);
 384
 385         ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
 386         irg_walk_graph(irg, normal_cost_walker,  NULL, inst);
 387         irg_walk_graph(irg, collect_roots, NULL, NULL);
 388         inc_irg_visited(irg);
 389         ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
 390         irg_block_walk_graph(irg, normal_sched_block, NULL, heights);
 391         ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
 392
 393         heights_free(heights);
 394
 395         return inst;
 396 }
 397
 398 static void *normal_init_block(void *graph_env, ir_node *block)
 399 {
 400         instance_t* inst  = (instance_t*)graph_env;
 401         ir_node**   sched = (ir_node**)get_irn_link(block);
 402         ir_node*    first = NULL;
 403         int         i;
 404
 405         /* turn into a list, so we can easily remove nodes.
 406            The link field is used anyway. */
 407         for (i = ARR_LEN(sched) - 1; i >= 0; --i) {
 408                 ir_node* irn = sched[i];
 409                 if (!is_cfop(irn)) {
 410                         set_irn_link(irn, first);
 411                         first = irn;
 412                 }
 413         }
 414         /* note: we can free sched here, there should be no attempt to schedule
 415            a block twice */
 416         DEL_ARR_F(sched);
 417         set_irn_link(block, sched);
 418         inst->curr_list = first;
 419         return inst;
 420 }
 421
 422 static void normal_finish_graph(void *env)
 423 {
 424         instance_t *inst = (instance_t*)env;
 425
 426         /* block uses the link field to store the schedule */
 427         ir_free_resources(inst->irg, IR_RESOURCE_IRN_LINK);
 428         obstack_free(&inst->obst, NULL);
 429         xfree(inst);
 430 }
 431
 432 static void sched_normal(ir_graph *irg)
 433 {
 434         static const list_sched_selector_t normal_selector = {
 435                 normal_init_graph,
 436                 normal_init_block,
 437                 normal_select,
 438                 NULL,              /* node_ready */
 439                 NULL,              /* node_selected */
 440                 NULL,              /* finish_block */
 441                 normal_finish_graph
 442         };
 443         be_list_sched_graph(irg, &normal_selector);
 444 }
 445
 446 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_sched_normal)
 447 void be_init_sched_normal(void)
 448 {
 449         be_register_scheduler("normal", sched_normal);
 450 }