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