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
 112         if (mode == mode_M || mode == mode_X)
 113                 return 0;
 114
 115         if (arch_get_register_req_out(irn)->type & arch_register_req_type_ignore)
 116                 return 0;
 117
 118         return 1;
 119 }
 120
 121
 122 /* TODO high cost for store trees
 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         ir_node*       last;
 131         int            n_res;
 132         int            cost;
 133         int            n_op_res = 0;
 134         int            i;
 135
 136         if (be_is_Keep(irn))
 137                 return 0;
 138
 139         if (is_Proj(irn)) {
 140                 return normal_tree_cost(get_Proj_pred(irn));
 141         }
 142
 143         if (fc == NULL) {
 144                 irn_cost_pair* costs;
 145                 int            i;
 146
 147                 fc = xmalloc(sizeof(*fc) + sizeof(*fc->costs) * arity);
 148                 fc->no_root = 0;
 149                 costs = fc->costs;
 150
 151                 for (i = 0; i < arity; ++i) {
 152                         ir_node* pred = get_irn_n(irn, i);
 153                         int cost;
 154
 155                         if (is_Phi(irn) || get_irn_mode(pred) == mode_M || is_Block(pred)) {
 156                                 cost = 0;
 157                         } else if (get_nodes_block(pred) != block) {
 158                                 cost = 1;
 159                         } else {
 160                                 flag_and_cost* pred_fc;
 161                                 ir_node*       real_pred;
 162
 163                                 cost = normal_tree_cost(pred);
 164                                 if (be_is_Barrier(pred)) cost = 1; // XXX hack: the barrier causes all users to have a reguse of #regs
 165                                 if (!arch_irn_is_ignore(pred)) {
 166                                         real_pred = (is_Proj(pred) ? get_Proj_pred(pred) : pred);
 167                                         pred_fc = get_irn_link(real_pred);
 168                                         pred_fc->no_root = 1;
 169 #if defined NORMAL_DBG
 170                                         ir_fprintf(stderr, "%+F says that %+F is no root\n", irn, real_pred);
 171 #endif
 172                                 }
 173                         }
 174
 175                         costs[i].irn  = pred;
 176                         costs[i].cost = cost;
 177                 }
 178
 179                 qsort(costs, arity, sizeof(*costs), cost_cmp);
 180                 set_irn_link(irn, fc);
 181         }
 182
 183         cost = 0;
 184         last = 0;
 185         for (i = 0; i < arity; ++i) {
 186                 ir_node* op = fc->costs[i].irn;
 187                 if (op == last)                 continue;
 188                 if (get_irn_mode(op) == mode_M) continue;
 189                 if (arch_irn_is_ignore(op))     continue;
 190                 cost = MAX(fc->costs[i].cost + n_op_res, cost);
 191                 last = op;
 192                 ++n_op_res;
 193         }
 194         n_res = count_result(irn);
 195         cost = MAX(n_res, cost);
 196
 197 #if defined NORMAL_DBG
 198         ir_fprintf(stderr, "reguse of %+F is %d\n", irn, cost);
 199 #endif
 200
 201         return cost;
 202 }
 203
 204
 205 static void normal_cost_walker(ir_node* irn, void* env)
 206 {
 207         (void)env;
 208
 209 #if defined NORMAL_DBG
 210         ir_fprintf(stderr, "cost walking node %+F\n", irn);
 211 #endif
 212         if (is_Block(irn)) return;
 213         if (!must_be_scheduled(irn)) return;
 214         normal_tree_cost(irn);
 215 }
 216
 217
 218 static void collect_roots(ir_node* irn, void* env)
 219 {
 220         int is_root;
 221
 222         (void)env;
 223
 224         if (is_Block(irn)) return;
 225         if (!must_be_scheduled(irn)) return;
 226
 227         is_root = be_is_Keep(irn) || !((flag_and_cost*)get_irn_link(irn))->no_root;
 228
 229 #if defined NORMAL_DBG
 230         ir_fprintf(stderr, "%+F is %sroot\n", irn, is_root ? "" : "no ");
 231 #endif
 232
 233         if (is_root) {
 234                 ir_node* block = get_nodes_block(irn);
 235                 ir_node** roots = get_irn_link(block);
 236                 if (roots == NULL) {
 237                         roots = NEW_ARR_F(ir_node*, 0);
 238                 }
 239                 ARR_APP1(ir_node*, roots, irn);
 240                 set_irn_link(block, roots);
 241         }
 242 }
 243
 244
 245 static ir_node** sched_node(ir_node** sched, ir_node* irn)
 246 {
 247         ir_node*       block = get_nodes_block(irn);
 248         flag_and_cost* fc    = get_irn_link(irn);
 249         irn_cost_pair* irns  = fc->costs;
 250         int            arity = get_irn_arity(irn);
 251         int            i;
 252
 253         if (irn_visited_else_mark(irn)) return sched;
 254         if (is_End(irn))                return sched;
 255
 256         if (!is_Phi(irn) && !be_is_Keep(irn)) {
 257                 for (i = 0; i < arity; ++i) {
 258                         ir_node* pred = irns[i].irn;
 259                         if (get_nodes_block(pred) != block) continue;
 260                         if (get_irn_mode(pred) == mode_M) continue;
 261                         if (is_Proj(pred)) pred = get_Proj_pred(pred);
 262                         sched = sched_node(sched, pred);
 263                 }
 264         }
 265
 266         ARR_APP1(ir_node*, sched, irn);
 267         return sched;
 268 }
 269
 270
 271 static int root_cmp(const void* a, const void* b)
 272 {
 273         const irn_cost_pair* const a1 = a;
 274         const irn_cost_pair* const b1 = b;
 275         int ret;
 276         if (is_irn_forking(a1->irn)) {
 277                 ret = 1;
 278         } else if (is_irn_forking(b1->irn)) {
 279                 ret = -1;
 280         } else {
 281                 ret = b1->cost - a1->cost;
 282                 if (ret == 0) {
 283                         /* place live-out nodes later */
 284                         ret = (count_result(a1->irn) != 0) - (count_result(b1->irn) != 0);
 285                 }
 286         }
 287 #if defined NORMAL_DBG
 288         ir_fprintf(stderr, "root %+F %s %+F\n", a1->irn, ret < 0 ? "<" : ret > 0 ? ">" : "=", b1->irn);
 289 #endif
 290         return ret;
 291 }
 292
 293
 294 static void normal_sched_block(ir_node* block, void* env)
 295 {
 296         heights_t*     heights = env;
 297         ir_node**      roots   = get_irn_link(block);
 298         int            root_count;
 299         irn_cost_pair* root_costs;
 300         int i;
 301         ir_node**      sched;
 302
 303 #if defined NORMAL_DBG
 304         ir_fprintf(stderr, "sched walking block %+F\n", block);
 305 #endif
 306
 307         if (roots == NULL) {
 308 #if defined NORMAL_DBG
 309                 fprintf(stderr, "has no roots\n");
 310 #endif
 311                 return;
 312         }
 313
 314         root_count = ARR_LEN(roots);
 315         NEW_ARR_A(irn_cost_pair, root_costs, root_count);
 316         for (i = 0; i < root_count; ++i) {
 317                 root_costs[i].irn  = roots[i];
 318                 root_costs[i].cost = get_irn_height(heights, roots[i]);
 319 #if defined NORMAL_DBG
 320                 ir_fprintf(stderr, "height of %+F is %u\n", roots[i], root_costs[i].cost);
 321 #endif
 322         }
 323         qsort(root_costs, root_count, sizeof(*root_costs), root_cmp);
 324 #if defined NORMAL_DBG
 325         {
 326                 int n = root_count;
 327                 int i;
 328
 329                 ir_fprintf(stderr, "Root Scheduling of %+F:\n", block);
 330                 for (i = 0; i < n; ++i) {
 331                         ir_fprintf(stderr, "  %+F\n", root_costs[i].irn);
 332                 }
 333                 fprintf(stderr, "\n");
 334         }
 335 #endif
 336
 337         sched = NEW_ARR_F(ir_node*, 0);
 338         for (i = 0; i < root_count; ++i) {
 339                 ir_node* irn = root_costs[i].irn;
 340                 assert(must_be_scheduled(irn));
 341                 sched = sched_node(sched, irn);
 342         }
 343         set_irn_link(block, sched);
 344         DEL_ARR_F(roots);
 345
 346 #if defined NORMAL_DBG
 347         {
 348                 int n = ARR_LEN(sched);
 349                 int i;
 350
 351                 ir_fprintf(stderr, "Scheduling of %+F:\n", block);
 352                 for (i = 0; i < n; ++i) {
 353                         ir_fprintf(stderr, "  %+F\n", sched[i]);
 354                 }
 355                 fprintf(stderr, "\n");
 356         }
 357 #endif
 358 }
 359
 360
 361 static void *normal_init_graph(const list_sched_selector_t *vtab,
 362                                const be_irg_t *birg)
 363 {
 364         ir_graph  *irg = be_get_birg_irg(birg);
 365         heights_t *heights;
 366
 367         (void)vtab;
 368
 369         be_clear_links(irg);
 370
 371         heights = heights_new(irg);
 372
 373         ir_reserve_resources(irg, IR_RESOURCE_IRN_LINK);
 374         irg_walk_graph(irg, normal_cost_walker,  NULL, NULL);
 375         irg_walk_graph(irg, collect_roots, NULL, NULL);
 376         inc_irg_visited(irg);
 377         ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
 378         irg_block_walk_graph(irg, normal_sched_block, NULL, heights);
 379         ir_free_resources(irg, IR_RESOURCE_IRN_LINK | IR_RESOURCE_IRN_VISITED);
 380
 381         heights_free(heights);
 382
 383         return NULL;
 384 }
 385
 386
 387 static void *normal_init_block(void *graph_env, ir_node *block)
 388 {
 389         (void)graph_env;
 390         (void)block;
 391
 392         return NULL;
 393 }
 394
 395
 396 const list_sched_selector_t normal_selector = {
 397         normal_init_graph,
 398         normal_init_block,
 399         normal_select,
 400         NULL,              /* to_appear_in_schedule */
 401         NULL,              /* node_ready */
 402         NULL,              /* node_selected */
 403         NULL,              /* exectime */
 404         NULL,              /* latency */
 405         NULL,              /* finish_block */
 406         NULL               /* finish_graph */
 407 };