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

   1 /**
   2  * @file   beifg_std.c
   3  * @date   18.11.2005
   4  * @author Sebastian Hack
   5  *
   6  * Copyright (C) 2005 Universitaet Karlsruhe
   7  * Released under the GPL
   8  */
   9
  10 #ifdef HAVE_CONFIG_H
  11 #include "config.h"
  12 #endif
  13
  14 #include <stdlib.h>
  15
  16 #include "list.h"
  17
  18 #include "irnode_t.h"
  19 #include "irnodeset.h"
  20 #include "irgraph_t.h"
  21 #include "irgwalk.h"
  22
  23 #include "be_t.h"
  24 #include "belive_t.h"
  25 #include "bera.h"
  26 #include "beifg_t.h"
  27 #include "bechordal_t.h"
  28
  29 #define MAX(x, y) ((x) > (y) ? (x) : (y))
  30
  31 typedef struct _ifg_std_t ifg_std_t;
  32
  33 struct _ifg_std_t {
  34         const be_ifg_impl_t *impl;
  35         const be_chordal_env_t *env;
  36 };
  37
  38 static void ifg_std_free(void *self)
  39 {
  40         free(self);
  41 }
  42
  43 static int ifg_std_connected(const void *self, const ir_node *a, const ir_node *b)
  44 {
  45         const ifg_std_t *ifg = self;
  46         be_lv_t *lv = ifg->env->birg->lv;
  47         return values_interfere(lv, a, b);
  48 }
  49
  50 typedef struct _nodes_iter_t {
  51         const be_chordal_env_t *env;
  52         struct obstack obst;
  53         int n;
  54         int curr;
  55         ir_node **nodes;
  56 } nodes_iter_t;
  57
  58 static void nodes_walker(ir_node *bl, void *data)
  59 {
  60         nodes_iter_t *it = data;
  61         struct list_head *head = get_block_border_head(it->env, bl);
  62
  63         border_t *b;
  64
  65         foreach_border_head(head, b) {
  66                 if(b->is_def && b->is_real) {
  67                         obstack_ptr_grow(&it->obst, b->irn);
  68                         it->n++;
  69                 }
  70         }
  71 }
  72
  73 static void find_nodes(const void *self, void *iter) {
  74         const ifg_std_t *ifg = self;
  75         nodes_iter_t *it = iter;
  76
  77         obstack_init(&it->obst);
  78         it->n     = 0;
  79         it->curr  = 0;
  80         it->env   = ifg->env;
  81
  82         irg_block_walk_graph(ifg->env->irg, nodes_walker, NULL, iter);
  83         obstack_ptr_grow(&it->obst, NULL);
  84         it->nodes = obstack_finish(&it->obst);
  85 }
  86
  87 static INLINE void node_break(nodes_iter_t *it, int force)
  88 {
  89         if((it->curr >= it->n || force) && it->nodes) {
  90                 obstack_free(&it->obst, NULL);
  91                 it->nodes = NULL;
  92         }
  93 }
  94
  95 static ir_node *get_next_node(void *iter)
  96 {
  97         nodes_iter_t *it = iter;
  98         ir_node *res     = NULL;
  99
 100         if(it->curr < it->n)
 101                 res = it->nodes[it->curr++];
 102
 103         node_break(it, 0);
 104
 105         return res;
 106 }
 107
 108 static ir_node *ifg_std_nodes_begin(const void *self, void *iter)
 109 {
 110         find_nodes(self, iter);
 111         return get_next_node(iter);
 112 }
 113
 114 static ir_node *ifg_std_nodes_next(const void *self, void *iter)
 115 {
 116         return get_next_node(iter);
 117 }
 118
 119 static void ifg_std_nodes_break(const void *self, void *iter)
 120 {
 121         node_break(iter, 1);
 122 }
 123
 124 typedef struct _adj_iter_t {
 125         const be_chordal_env_t *env;
 126         const ir_node        *irn;
 127         int                   valid;
 128         ir_nodeset_t          neighbours;
 129         ir_nodeset_iterator_t iter;
 130 } adj_iter_t;
 131
 132 static void find_neighbour_walker(ir_node *block, void *data)
 133 {
 134         adj_iter_t *it          = data;
 135         struct list_head *head  = get_block_border_head(it->env, block);
 136
 137         border_t *b;
 138         int has_started = 0;
 139
 140         if(!be_is_live_in(it->env->birg->lv, block, it->irn) && block != get_nodes_block(it->irn))
 141                 return;
 142
 143         foreach_border_head(head, b) {
 144                 ir_node *irn = b->irn;
 145
 146                 if(irn == it->irn) {
 147                         if(b->is_def)
 148                                 has_started = 1;
 149                         else
 150                                 break; /* if we reached the end of the node's lifetime we can safely break */
 151                 }
 152                 else if(b->is_def) {
 153                         /* if any other node than the one in question starts living, add it to the set */
 154                         ir_nodeset_insert(&it->neighbours, irn);
 155                 }
 156                 else if(!has_started) {
 157                         /* we only delete, if the live range in question has not yet started */
 158                         ir_nodeset_remove(&it->neighbours, irn);
 159                 }
 160
 161         }
 162 }
 163
 164 static void find_neighbours(const ifg_std_t *ifg, adj_iter_t *it, const ir_node *irn)
 165 {
 166         it->env         = ifg->env;
 167         it->irn         = irn;
 168         it->valid       = 1;
 169         ir_nodeset_init(&it->neighbours);
 170
 171         dom_tree_walk(get_nodes_block(irn), find_neighbour_walker, NULL, it);
 172
 173         ir_nodeset_iterator_init(&it->iter, &it->neighbours);
 174 }
 175
 176 static INLINE void neighbours_break(adj_iter_t *it, int force)
 177 {
 178         assert(it->valid == 1);
 179         ir_nodeset_destroy(&it->neighbours);
 180         it->valid = 0;
 181 }
 182
 183 static ir_node *get_next_neighbour(adj_iter_t *it) {
 184         ir_node *res = ir_nodeset_iterator_next(&it->iter);
 185
 186         if (res == NULL) {
 187                 ir_nodeset_destroy(&it->neighbours);
 188         }
 189         return res;
 190 }
 191
 192 static ir_node *ifg_std_neighbours_begin(const void *self, void *iter, const ir_node *irn)
 193 {
 194         adj_iter_t *it = iter;
 195         find_neighbours(self, iter, irn);
 196         return ir_nodeset_iterator_next(&it->iter);
 197 }
 198
 199 static ir_node *ifg_std_neighbours_next(const void *self, void *iter)
 200 {
 201         return get_next_neighbour(iter);
 202 }
 203
 204 static void ifg_std_neighbours_break(const void *self, void *iter)
 205 {
 206         neighbours_break(iter, 1);
 207 }
 208
 209 typedef struct _cliques_iter_t {
 210         struct obstack ob;
 211         const be_chordal_env_t *cenv;
 212         ir_node **buf;
 213         ir_node **blocks;
 214         int n_blocks, blk;
 215         struct list_head *bor;
 216         pset *living;
 217 } cliques_iter_t;
 218
 219 static INLINE void free_clique_iter(cliques_iter_t *it) {
 220         it->n_blocks = -1;
 221         obstack_free(&it->ob, NULL);
 222         del_pset(it->living);
 223 }
 224
 225 static void get_blocks_dom_order(ir_node *blk, void *env) {
 226         cliques_iter_t *it = env;
 227         obstack_ptr_grow(&it->ob, blk);
 228 }
 229
 230 #define pset_foreach(pset, irn)  for(irn=pset_first(pset); irn; irn=pset_next(pset))
 231
 232
 233 /**
 234  * NOTE: Be careful when changing this function!
 235  *       First understand the control flow of consecutive calls.
 236  */
 237 static INLINE int get_next_clique(cliques_iter_t *it) {
 238
 239         /* continue in the block we left the last time */
 240         for (; it->blk < it->n_blocks; it->blk++) {
 241                 int output_on_shrink = 0;
 242                 struct list_head *head = get_block_border_head(it->cenv, it->blocks[it->blk]);
 243
 244                 /* on entry to a new block set the first border ... */
 245                 if (!it->bor)
 246                         it->bor = head->prev;
 247
 248                 /* ... otherwise continue with the border we left the last time */
 249                 for (; it->bor != head; it->bor = it->bor->prev) {
 250                         border_t *b = list_entry(it->bor, border_t, list);
 251
 252                         /* if its a definition irn starts living */
 253                         if (b->is_def) {
 254                                 pset_insert_ptr(it->living, b->irn);
 255                                 if (b->is_real)
 256                                         output_on_shrink = 1;
 257                         } else
 258
 259                         /* if its the last usage the irn dies */
 260                         {
 261                                 /* before shrinking the set, return the current maximal clique */
 262                                 if (output_on_shrink) {
 263                                         int count = 0;
 264                                         ir_node *irn;
 265
 266                                         /* fill the output buffer */
 267                                         pset_foreach(it->living, irn)
 268                                                 it->buf[count++] = irn;
 269
 270                                         assert(count > 0 && "We have a 'last usage', so there must be sth. in it->living");
 271
 272                                         return count;
 273                                 }
 274
 275                                 pset_remove_ptr(it->living, b->irn);
 276                         }
 277                 }
 278
 279                 it->bor = NULL;
 280                 assert(0 == pset_count(it->living) && "Something has survived! (At the end of the block it->living must be empty)");
 281         }
 282
 283         if (it->n_blocks != -1)
 284                 free_clique_iter(it);
 285
 286         return -1;
 287 }
 288
 289 static int ifg_std_cliques_begin(const void *self, void *iter, ir_node **buf)
 290 {
 291         const ifg_std_t *ifg = self;
 292         cliques_iter_t *it = iter;
 293         ir_node *start_bl = get_irg_start_block(ifg->env->irg);
 294
 295         obstack_init(&it->ob);
 296         dom_tree_walk(start_bl, get_blocks_dom_order, NULL, it);
 297
 298         it->cenv     = ifg->env;
 299         it->buf      = buf;
 300         it->n_blocks = obstack_object_size(&it->ob) / sizeof(void *);
 301         it->blocks   = obstack_finish(&it->ob);
 302         it->blk      = 0;
 303         it->bor      = NULL;
 304         it->living   = pset_new_ptr(2 * arch_register_class_n_regs(it->cenv->cls));
 305
 306         return get_next_clique(it);
 307 }
 308
 309 static int ifg_std_cliques_next(const void *self, void *iter)
 310 {
 311         return get_next_clique(iter);
 312 }
 313
 314 static void ifg_std_cliques_break(const void *self, void *iter)
 315 {
 316         free_clique_iter(iter);
 317 }
 318
 319
 320 static int ifg_std_degree(const void *self, const ir_node *irn)
 321 {
 322         adj_iter_t it;
 323         int degree;
 324         find_neighbours(self, &it, irn);
 325         degree = ir_nodeset_size(&it.neighbours);
 326         neighbours_break(&it, 1);
 327         return degree;
 328 }
 329
 330 static const be_ifg_impl_t ifg_std_impl = {
 331         sizeof(nodes_iter_t),
 332         sizeof(adj_iter_t),
 333         sizeof(cliques_iter_t),
 334
 335         ifg_std_free,
 336         ifg_std_connected,
 337         ifg_std_neighbours_begin,
 338         ifg_std_neighbours_next,
 339         ifg_std_neighbours_break,
 340         ifg_std_nodes_begin,
 341         ifg_std_nodes_next,
 342         ifg_std_nodes_break,
 343         ifg_std_cliques_begin,
 344         ifg_std_cliques_next,
 345         ifg_std_cliques_break,
 346         ifg_std_degree
 347 };
 348
 349 be_ifg_t *be_ifg_std_new(const be_chordal_env_t *env)
 350 {
 351         ifg_std_t *ifg = xmalloc(sizeof(*ifg));
 352
 353         ifg->impl = &ifg_std_impl;
 354         ifg->env  = env;
 355
 356         return (be_ifg_t *) ifg;
 357 }