nsz Git - libfirm/blob - ir/be/beschednormal.c

   1 /*
   2  * Copyright (C) 1995-2007 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 "irtools.h"
  36 #include "irgwalk.h"
  37
  38
  39 // XXX there is no one time init for schedulers
  40 //#define NORMAL_DBG
  41
  42
  43 static const arch_env_t *cur_arch_env;
  44
  45
  46 static ir_node *normal_select(void *block_env, ir_nodeset_t *ready_set,
  47                               ir_nodeset_t *live_set)
  48 {
  49         ir_nodeset_iterator_t iter;
  50         ir_node*  block;
  51         ir_node*  irn;
  52         ir_node** sched;
  53         int sched_count;
  54
  55         (void)block_env;
  56         (void)live_set;
  57
  58         ir_nodeset_iterator_init(&iter, ready_set);
  59         irn = ir_nodeset_iterator_next(&iter);
  60         block = get_nodes_block(irn);
  61         sched = get_irn_link(block);
  62         sched_count = ARR_LEN(sched);
  63         for (; sched_count-- != 0; ++sched) {
  64                 ir_node* irn = *sched;
  65                 if (ir_nodeset_contains(ready_set, irn) &&
  66                                 !arch_irn_class_is(cur_arch_env, irn, branch)) {
  67 #if defined NORMAL_DBG
  68                         ir_fprintf(stderr, "scheduling %+F\n", irn);
  69 #endif
  70                         return irn;
  71                 }
  72         }
  73
  74         return irn;
  75 }
  76
  77
  78 typedef struct irn_cost_pair {
  79         ir_node* irn;
  80         int      cost;
  81 } irn_cost_pair;
  82
  83
  84 static int cost_cmp(const void* a, const void* b)
  85 {
  86         const irn_cost_pair* a1 = a;
  87         const irn_cost_pair* b1 = b;
  88         return b1->cost - a1->cost;
  89 }
  90
  91
  92 typedef struct flag_and_cost {
  93         int no_root;
  94         irn_cost_pair costs[];
  95 } flag_and_cost;
  96
  97
  98 static int count_result(const ir_node* irn)
  99 {
 100         const ir_mode* mode = get_irn_mode(irn);
 101         return
 102                 mode != mode_M &&
 103                 mode != mode_X &&
 104                 !arch_irn_is(cur_arch_env, irn, ignore);
 105 }
 106
 107
 108 static int normal_tree_cost(ir_node* irn)
 109 {
 110         flag_and_cost* fc    = get_irn_link(irn);
 111         ir_node*       block = get_nodes_block(irn);
 112         int            arity = get_irn_arity(irn);
 113         int            cost_max  = 0;
 114         int            count_max = 0;
 115         int            n_res;
 116         int            cost;
 117         int            n_op_res = 0;
 118         int            i;
 119
 120         if (fc == NULL) {
 121                 irn_cost_pair* costs;
 122                 int            i;
 123
 124                 fc = malloc(sizeof(*fc) + sizeof(*fc->costs) * arity);
 125                 fc->no_root = 0;
 126                 costs = fc->costs;
 127
 128                 for (i = 0; i < arity; ++i) {
 129                         ir_node* pred = get_irn_n(irn, i);
 130                         int cost;
 131
 132                         if (is_Phi(irn) || get_irn_mode(pred) == mode_M || is_Block(pred)) {
 133                                 cost = 0;
 134                         } else if (get_nodes_block(pred) != block) {
 135                                 cost = 1;
 136                         } else {
 137                                 flag_and_cost* pred_fc;
 138
 139                                 cost = normal_tree_cost(pred);
 140                                 if (be_is_Barrier(pred)) cost = 1; // XXX hack: the barrier causes all users to have a reguse of #regs
 141                                 pred_fc = get_irn_link(pred);
 142                                 pred_fc->no_root = 1;
 143 #if defined NORMAL_DBG
 144                                 ir_fprintf(stderr, "%+F says that %+F is no root\n", irn, pred);
 145 #endif
 146                         }
 147
 148                         costs[i].irn  = pred;
 149                         costs[i].cost = cost;
 150
 151                         if (cost > cost_max) {
 152                                 cost_max  = cost;
 153                                 count_max = 1;
 154                         } else if (cost == cost_max) {
 155                                 ++count_max;
 156                         }
 157                 }
 158
 159                 qsort(costs, arity, sizeof(*costs), cost_cmp);
 160                 set_irn_link(irn, fc);
 161         } else {
 162                 irn_cost_pair* costs = fc->costs;
 163                 int            i;
 164
 165                 if (arity > 0) {
 166                         cost_max = costs[0].cost;
 167
 168                         for (i = 0; i < arity; ++i) {
 169                                 if (costs[i].cost < cost_max) break;
 170                                 ++count_max;
 171                         }
 172                 }
 173         }
 174
 175         cost = 0;
 176         for (i = 0; i < arity; ++i) {
 177                 if (get_irn_mode(fc->costs[i].irn) == mode_M) continue;
 178                 if (arch_irn_is(cur_arch_env, fc->costs[i].irn, ignore)) continue;
 179                 cost = MAX(fc->costs[i].cost + n_op_res, cost);
 180                 ++n_op_res;
 181         }
 182         n_res = count_result(irn);
 183         cost = MAX(n_res, cost);
 184
 185 #if defined NORMAL_DBG
 186         ir_fprintf(stderr, "reguse of %+F is %d\n", irn, cost);
 187 #endif
 188
 189         return cost;
 190 }
 191
 192
 193 static void normal_cost_walker(ir_node* irn, void* env)
 194 {
 195         (void)env;
 196
 197 #if defined NORMAL_DBG
 198         ir_fprintf(stderr, "cost walking node %+F\n", irn);
 199 #endif
 200         if (is_Block(irn)) return;
 201         normal_tree_cost(irn);
 202 }
 203
 204
 205 static void collect_roots(ir_node* irn, void* env)
 206 {
 207         flag_and_cost* fc;
 208
 209         (void)env;
 210
 211         if (is_Block(irn)) return;
 212
 213         fc = get_irn_link(irn);
 214
 215 #if defined NORMAL_DBG
 216         ir_fprintf(stderr, "%+F is %sroot\n", irn, fc->no_root ? "no " : "");
 217 #endif
 218
 219         if (!fc->no_root) {
 220                 ir_node* block = get_nodes_block(irn);
 221                 ir_node** roots = get_irn_link(block);
 222                 if (roots == NULL) {
 223                         roots = NEW_ARR_F(ir_node*, 0);
 224                 }
 225                 ARR_APP1(ir_node*, roots, irn);
 226                 set_irn_link(block, roots);
 227         }
 228 }
 229
 230
 231 static ir_node** sched_node(ir_node** sched, ir_node* irn)
 232 {
 233         ir_node*       block = get_nodes_block(irn);
 234         flag_and_cost* fc    = get_irn_link(irn);
 235         irn_cost_pair* irns  = fc->costs;
 236         int            arity = get_irn_arity(irn);
 237         int            i;
 238
 239         if (irn_visited(irn)) return sched;
 240
 241         if (is_End(irn)) return sched;
 242
 243         if (!is_Phi(irn)) {
 244                 for (i = 0; i < arity; ++i) {
 245                         ir_node* pred = irns[i].irn;
 246                         if (get_nodes_block(pred) != block) continue;
 247                         if (get_irn_mode(pred) == mode_M) continue;
 248                         sched = sched_node(sched, pred);
 249                 }
 250         }
 251
 252         mark_irn_visited(irn);
 253         ARR_APP1(ir_node*, sched, irn);
 254         return sched;
 255 }
 256
 257
 258 static void normal_sched_block(ir_node* block, void* env)
 259 {
 260         ir_node** roots = get_irn_link(block);
 261         int            root_count;
 262         irn_cost_pair* root_costs;
 263         int i;
 264         ir_node**      sched;
 265
 266         (void)env;
 267
 268 #if defined NORMAL_DBG
 269         ir_fprintf(stderr, "sched walking block %+F\n", block);
 270 #endif
 271
 272         if (roots == NULL) {
 273 #if defined NORMAL_DBG
 274                 fprintf(stderr, "has no roots\n");
 275 #endif
 276                 return;
 277         }
 278
 279         root_count = ARR_LEN(roots);
 280         NEW_ARR_A(irn_cost_pair, root_costs, root_count);
 281         for (i = 0; i < root_count; ++i) {
 282                 root_costs[i].irn  = roots[i];
 283                 root_costs[i].cost = normal_tree_cost(roots[i]);
 284         }
 285         qsort(root_costs, root_count, sizeof(*root_costs), cost_cmp);
 286
 287         sched = NEW_ARR_F(ir_node*, 0);
 288         for (i = 0; i < root_count; ++i) {
 289                 ir_node* irn = root_costs[i].irn;
 290                 sched = sched_node(sched, irn);
 291         }
 292         set_irn_link(block, sched);
 293         DEL_ARR_F(roots);
 294
 295 #if defined NORMAL_DBG
 296         {
 297                 int n = ARR_LEN(sched);
 298                 int i;
 299
 300                 ir_fprintf(stderr, "Scheduling of %+F:\n", block);
 301                 for (i = 0; i < n; ++i) {
 302                         ir_fprintf(stderr, "  %+F\n", sched[i]);
 303                 }
 304                 fprintf(stderr, "\n");
 305         }
 306 #endif
 307 }
 308
 309
 310 static void *normal_init_graph(const list_sched_selector_t *vtab,
 311                                const be_irg_t *birg)
 312 {
 313         ir_graph* irg = be_get_birg_irg(birg);
 314
 315         (void)vtab;
 316
 317         cur_arch_env = be_get_birg_arch_env(birg);
 318
 319         be_clear_links(irg);
 320
 321         irg_walk_graph(irg, normal_cost_walker,  NULL, NULL);
 322         irg_walk_graph(irg, collect_roots, NULL, NULL);
 323         inc_irg_visited(irg);
 324         irg_block_walk_graph(irg, normal_sched_block, NULL, NULL);
 325
 326         return NULL;
 327 }
 328
 329
 330 static void *normal_init_block(void *graph_env, ir_node *block)
 331 {
 332         (void)graph_env;
 333         (void)block;
 334
 335         return NULL;
 336 }
 337
 338
 339 const list_sched_selector_t normal_selector = {
 340         normal_init_graph,
 341         normal_init_block,
 342         normal_select,
 343         NULL,              /* to_appear_in_schedule */
 344         NULL,              /* node_ready */
 345         NULL,              /* node_selected */
 346         NULL,              /* exectime */
 347         NULL,              /* latency */
 348         NULL,              /* finish_block */
 349         NULL               /* finish_graph */
 350 };