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         return res;
 187 }
 188
 189 static ir_node *ifg_std_neighbours_begin(const void *self, void *iter, const ir_node *irn)
 190 {
 191         adj_iter_t *it = iter;
 192         find_neighbours(self, iter, irn);
 193         return ir_nodeset_iterator_next(&it->iter);
 194 }
 195
 196 static ir_node *ifg_std_neighbours_next(const void *self, void *iter)
 197 {
 198         return get_next_neighbour(iter);
 199 }
 200
 201 static void ifg_std_neighbours_break(const void *self, void *iter)
 202 {
 203         neighbours_break(iter, 1);
 204 }
 205
 206 typedef struct _cliques_iter_t {
 207         struct obstack ob;
 208         const be_chordal_env_t *cenv;
 209         ir_node **buf;
 210         ir_node **blocks;
 211         int n_blocks, blk;
 212         struct list_head *bor;
 213         pset *living;
 214 } cliques_iter_t;
 215
 216 static INLINE void free_clique_iter(cliques_iter_t *it) {
 217         it->n_blocks = -1;
 218         obstack_free(&it->ob, NULL);
 219         del_pset(it->living);
 220 }
 221
 222 static void get_blocks_dom_order(ir_node *blk, void *env) {
 223         cliques_iter_t *it = env;
 224         obstack_ptr_grow(&it->ob, blk);
 225 }
 226
 227 #define pset_foreach(pset, irn)  for(irn=pset_first(pset); irn; irn=pset_next(pset))
 228
 229
 230 /**
 231  * NOTE: Be careful when changing this function!
 232  *       First understand the control flow of consecutive calls.
 233  */
 234 static INLINE int get_next_clique(cliques_iter_t *it) {
 235
 236         /* continue in the block we left the last time */
 237         for (; it->blk < it->n_blocks; it->blk++) {
 238                 int output_on_shrink = 0;
 239                 struct list_head *head = get_block_border_head(it->cenv, it->blocks[it->blk]);
 240
 241                 /* on entry to a new block set the first border ... */
 242                 if (!it->bor)
 243                         it->bor = head->prev;
 244
 245                 /* ... otherwise continue with the border we left the last time */
 246                 for (; it->bor != head; it->bor = it->bor->prev) {
 247                         border_t *b = list_entry(it->bor, border_t, list);
 248
 249                         /* if its a definition irn starts living */
 250                         if (b->is_def) {
 251                                 pset_insert_ptr(it->living, b->irn);
 252                                 if (b->is_real)
 253                                         output_on_shrink = 1;
 254                         } else
 255
 256                         /* if its the last usage the irn dies */
 257                         {
 258                                 /* before shrinking the set, return the current maximal clique */
 259                                 if (output_on_shrink) {
 260                                         int count = 0;
 261                                         ir_node *irn;
 262
 263                                         /* fill the output buffer */
 264                                         pset_foreach(it->living, irn)
 265                                                 it->buf[count++] = irn;
 266
 267                                         assert(count > 0 && "We have a 'last usage', so there must be sth. in it->living");
 268
 269                                         return count;
 270                                 }
 271
 272                                 pset_remove_ptr(it->living, b->irn);
 273                         }
 274                 }
 275
 276                 it->bor = NULL;
 277                 assert(0 == pset_count(it->living) && "Something has survived! (At the end of the block it->living must be empty)");
 278         }
 279
 280         if (it->n_blocks != -1)
 281                 free_clique_iter(it);
 282
 283         return -1;
 284 }
 285
 286 static int ifg_std_cliques_begin(const void *self, void *iter, ir_node **buf)
 287 {
 288         const ifg_std_t *ifg = self;
 289         cliques_iter_t *it = iter;
 290         ir_node *start_bl = get_irg_start_block(ifg->env->irg);
 291
 292         obstack_init(&it->ob);
 293         dom_tree_walk(start_bl, get_blocks_dom_order, NULL, it);
 294
 295         it->cenv     = ifg->env;
 296         it->buf      = buf;
 297         it->n_blocks = obstack_object_size(&it->ob) / sizeof(void *);
 298         it->blocks   = obstack_finish(&it->ob);
 299         it->blk      = 0;
 300         it->bor      = NULL;
 301         it->living   = pset_new_ptr(2 * arch_register_class_n_regs(it->cenv->cls));
 302
 303         return get_next_clique(it);
 304 }
 305
 306 static int ifg_std_cliques_next(const void *self, void *iter)
 307 {
 308         return get_next_clique(iter);
 309 }
 310
 311 static void ifg_std_cliques_break(const void *self, void *iter)
 312 {
 313         free_clique_iter(iter);
 314 }
 315
 316
 317 static int ifg_std_degree(const void *self, const ir_node *irn)
 318 {
 319         adj_iter_t it;
 320         int degree;
 321         find_neighbours(self, &it, irn);
 322         degree = ir_nodeset_size(&it.neighbours);
 323         neighbours_break(&it, 1);
 324         return degree;
 325 }
 326
 327 static const be_ifg_impl_t ifg_std_impl = {
 328         sizeof(nodes_iter_t),
 329         sizeof(adj_iter_t),
 330         sizeof(cliques_iter_t),
 331
 332         ifg_std_free,
 333         ifg_std_connected,
 334         ifg_std_neighbours_begin,
 335         ifg_std_neighbours_next,
 336         ifg_std_neighbours_break,
 337         ifg_std_nodes_begin,
 338         ifg_std_nodes_next,
 339         ifg_std_nodes_break,
 340         ifg_std_cliques_begin,
 341         ifg_std_cliques_next,
 342         ifg_std_cliques_break,
 343         ifg_std_degree
 344 };
 345
 346 be_ifg_t *be_ifg_std_new(const be_chordal_env_t *env)
 347 {
 348         ifg_std_t *ifg = xmalloc(sizeof(*ifg));
 349
 350         ifg->impl = &ifg_std_impl;
 351         ifg->env  = env;
 352
 353         return (be_ifg_t *) ifg;
 354 }