nsz Git - libfirm/blob - ir/tr/tr_inheritance.c

   1 /*
   2  * Copyright (C) 1995-2011 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  * @file    tr_inheritance.c
  22  * @brief   Utility routines for inheritance representation
  23  * @author  Goetz Lindenmaier
  24  */
  25 #include "config.h"
  26
  27 #include "debug.h"
  28 #include "typerep.h"
  29 #include "irgraph_t.h"
  30 #include "irprog_t.h"
  31 #include "irprintf.h"
  32 #include "pset.h"
  33 #include "set.h"
  34 #include "irgwalk.h"
  35 #include "irflag.h"
  36
  37 /* ----------------------------------------------------------------------- */
  38 /* Resolve implicit inheritance.                                           */
  39 /* ----------------------------------------------------------------------- */
  40
  41 ident *default_mangle_inherited_name(const ir_entity *super, const ir_type *clss)
  42 {
  43         return id_mangle_u(new_id_from_str("inh"), id_mangle_u(get_class_ident(clss), get_entity_ident(super)));
  44 }
  45
  46 /** Replicates all entities in all super classes that are not overwritten
  47     by an entity of this class. */
  48 static void copy_entities_from_superclass(ir_type *clss, void *env)
  49 {
  50         size_t i;
  51         size_t j;
  52         size_t k;
  53         size_t l;
  54         int overwritten;
  55         ir_type *super;
  56         ir_entity *inhent, *thisent;
  57         mangle_inherited_name_func *mfunc = *(mangle_inherited_name_func **)env;
  58
  59         for (i = 0; i < get_class_n_supertypes(clss); i++) {
  60                 super = get_class_supertype(clss, i);
  61                 for (j = 0; j < get_class_n_members(super); j++) {
  62                         inhent = get_class_member(super, j);
  63                         /* check whether inhent is already overwritten */
  64                         overwritten = 0;
  65                         for (k = 0; (k < get_class_n_members(clss)) && (overwritten == 0); k++) {
  66                                 thisent = get_class_member(clss, k);
  67                                 for (l = 0; l < get_entity_n_overwrites(thisent); l++) {
  68                                         if (inhent == get_entity_overwrites(thisent, l)) {
  69                                                 /* overwritten - do not copy */
  70                                                 overwritten = 1;
  71                                                 break;
  72                                         }
  73                                 }
  74                         }
  75                         /* Inherit entity */
  76                         if (!overwritten) {
  77                                 thisent = copy_entity_own(inhent, clss);
  78                                 add_entity_overwrites(thisent, inhent);
  79                                 if (get_entity_peculiarity(inhent) == peculiarity_existent)
  80                                         set_entity_peculiarity(thisent, peculiarity_inherited);
  81                                 set_entity_ld_ident(thisent, mfunc(inhent, clss));
  82                                 if (get_entity_linkage(inhent) & IR_LINKAGE_CONSTANT) {
  83                                         assert(is_atomic_entity(inhent) &&  /* @@@ */
  84                                                 "Inheritance of constant, compound entities not implemented");
  85                                         add_entity_linkage(thisent, IR_LINKAGE_CONSTANT);
  86                                         set_atomic_ent_value(thisent, get_atomic_ent_value(inhent));
  87                                 }
  88                         }
  89                 }
  90         }
  91 }
  92
  93 void resolve_inheritance(mangle_inherited_name_func *mfunc)
  94 {
  95         if (!mfunc)
  96                 mfunc = default_mangle_inherited_name;
  97         class_walk_super2sub(copy_entities_from_superclass, NULL, (void *)&mfunc);
  98 }
  99
 100
 101 /* ----------------------------------------------------------------------- */
 102 /* The transitive closure of the subclass/superclass and                   */
 103 /* overwrites/overwrittenby relation.                                      */
 104 /*                                                                         */
 105 /* A walk over the ir (O(#types+#entities)) computes the transitive        */
 106 /* closure.  Adding a new type/entity or changing the basic relations in   */
 107 /* some other way invalidates the transitive closure, i.e., it is not      */
 108 /* updated by the basic functions.                                         */
 109 /*                                                                         */
 110 /* All functions are named as their counterparts for the basic relations,  */
 111 /* adding the infix 'trans_'.                                              */
 112 /* ----------------------------------------------------------------------- */
 113
 114 void                        set_irp_inh_transitive_closure_state(inh_transitive_closure_state s)
 115 {
 116         irp->inh_trans_closure_state = s;
 117 }
 118 void                        invalidate_irp_inh_transitive_closure_state(void)
 119 {
 120         if (irp->inh_trans_closure_state == inh_transitive_closure_valid)
 121                 irp->inh_trans_closure_state = inh_transitive_closure_invalid;
 122 }
 123 inh_transitive_closure_state get_irp_inh_transitive_closure_state(void)
 124 {
 125         return irp->inh_trans_closure_state;
 126 }
 127
 128 static void assert_valid_state(void)
 129 {
 130         assert(irp->inh_trans_closure_state == inh_transitive_closure_valid ||
 131                irp->inh_trans_closure_state == inh_transitive_closure_invalid);
 132 }
 133
 134 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
 135 /* There is a set that extends each entity/type with two new               */
 136 /* fields:  one for the upwards directed relation: 'up' (supertype,        */
 137 /* overwrites) and one for the downwards directed relation: 'down' (sub-   */
 138 /* type, overwrittenby.  These fields contain psets (and maybe later       */
 139 /* arrays) listing all subtypes...                                         */
 140 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
 141
 142 typedef enum {
 143         d_up   = 0,
 144         d_down = 1,
 145 } dir;
 146
 147 typedef struct {
 148         const firm_kind *kind;   /**< An entity or type. */
 149         pset *directions[2];
 150 } tr_inh_trans_tp;
 151
 152 /* We use this set for all types and entities.  */
 153 static set *tr_inh_trans_set = NULL;
 154
 155 /**
 156  * Compare two tr_inh_trans_tp entries.
 157  */
 158 static int tr_inh_trans_cmp(const void *e1, const void *e2, size_t size)
 159 {
 160         const tr_inh_trans_tp *ef1 = (const tr_inh_trans_tp*)e1;
 161         const tr_inh_trans_tp *ef2 = (const tr_inh_trans_tp*)e2;
 162         (void) size;
 163
 164         return ef1->kind != ef2->kind;
 165 }
 166
 167 /**
 168  * calculate the hash value of an tr_inh_trans_tp
 169  */
 170 static inline unsigned int tr_inh_trans_hash(const tr_inh_trans_tp *v)
 171 {
 172         return hash_ptr(v->kind);
 173 }
 174
 175 /* This always completes successfully. */
 176 static tr_inh_trans_tp *get_firm_kind_entry(const firm_kind *k)
 177 {
 178         tr_inh_trans_tp a, *found;
 179         a.kind = k;
 180
 181         if (!tr_inh_trans_set) tr_inh_trans_set = new_set(tr_inh_trans_cmp, 128);
 182
 183         found = set_find(tr_inh_trans_tp, tr_inh_trans_set, &a, sizeof(a), tr_inh_trans_hash(&a));
 184         if (!found) {
 185                 a.directions[d_up]   = pset_new_ptr(16);
 186                 a.directions[d_down] = pset_new_ptr(16);
 187                 found = set_insert(tr_inh_trans_tp, tr_inh_trans_set, &a, sizeof(a), tr_inh_trans_hash(&a));
 188         }
 189         return found;
 190 }
 191
 192 static pset *get_entity_map(const ir_entity *ent, dir d)
 193 {
 194         tr_inh_trans_tp *found;
 195
 196         assert(is_entity(ent));
 197         found = get_firm_kind_entry((const firm_kind *)ent);
 198         return found->directions[d];
 199 }
 200
 201 static pset *get_type_map(const ir_type *tp, dir d)
 202 {
 203         tr_inh_trans_tp *found;
 204
 205         assert(is_type(tp));
 206         found = get_firm_kind_entry((const firm_kind *)tp);
 207         return found->directions[d];
 208 }
 209
 210
 211 /**
 212  * Walk over all types reachable from tp in the sub/supertype
 213  * relation and compute the closure for the two downwards directed
 214  * relations.
 215  *
 216  * The walk in the dag formed by the relation is tricky:  We must visit
 217  * all subtypes before visiting the supertypes.  So we first walk down.
 218  * Then we can compute the closure for this type.  Then we walk up.
 219  * As we call ourselves recursive, and walk in both directions, there
 220  * can be cycles.  So we have to make sure, that if we visit a node
 221  * a second time (in a walk up) we do nothing.  For this we increment
 222  * the master visited flag twice.
 223  * If the type is marked with master_flag_visited-1 it is on the stack.
 224  * If it is marked with master_flag_visited it is fully processed.
 225  *
 226  * Well, we still miss some candidates ... */
 227 static void compute_down_closure(ir_type *tp)
 228 {
 229         pset *myset, *subset;
 230         size_t i, n_subtypes, n_members, n_supertypes;
 231         ir_visited_t master_visited = get_master_type_visited();
 232
 233         set_type_visited(tp, master_visited-1);
 234
 235         /* Recursive descend. */
 236         n_subtypes = get_class_n_subtypes(tp);
 237         for (i = 0; i < n_subtypes; ++i) {
 238                 ir_type *stp = get_class_subtype(tp, i);
 239                 if (get_type_visited(stp) < master_visited-1) {
 240                         compute_down_closure(stp);
 241                 }
 242         }
 243
 244         /* types */
 245         myset = get_type_map(tp, d_down);
 246         for (i = 0; i < n_subtypes; ++i) {
 247                 ir_type *stp = get_class_subtype(tp, i);
 248                 subset = get_type_map(stp, d_down);
 249                 pset_insert_ptr(myset, stp);
 250                 pset_insert_pset_ptr(myset, subset);
 251         }
 252
 253         /* entities */
 254         n_members = get_class_n_members(tp);
 255         for (i = 0; i < n_members; ++i) {
 256                 ir_entity *mem = get_class_member(tp, i);
 257                 size_t j, n_overwrittenby = get_entity_n_overwrittenby(mem);
 258
 259                 myset = get_entity_map(mem, d_down);
 260                 for (j = 0; j < n_overwrittenby; ++j) {
 261                         ir_entity *ov = get_entity_overwrittenby(mem, j);
 262                         subset = get_entity_map(ov, d_down);
 263                         pset_insert_ptr(myset, ov);
 264                         pset_insert_pset_ptr(myset, subset);
 265                 }
 266         }
 267
 268         mark_type_visited(tp);
 269
 270         /* Walk up. */
 271         n_supertypes = get_class_n_supertypes(tp);
 272         for (i = 0; i < n_supertypes; ++i) {
 273                 ir_type *stp = get_class_supertype(tp, i);
 274                 if (get_type_visited(stp) < master_visited-1) {
 275                         compute_down_closure(stp);
 276                 }
 277         }
 278 }
 279
 280 static void compute_up_closure(ir_type *tp)
 281 {
 282         pset *myset, *subset;
 283         size_t i, n_subtypes, n_members, n_supertypes;
 284         ir_visited_t master_visited = get_master_type_visited();
 285
 286         set_type_visited(tp, master_visited-1);
 287
 288         /* Recursive descend. */
 289         n_supertypes = get_class_n_supertypes(tp);
 290         for (i = 0; i < n_supertypes; ++i) {
 291                 ir_type *stp = get_class_supertype(tp, i);
 292                 if (get_type_visited(stp) < get_master_type_visited()-1) {
 293                         compute_up_closure(stp);
 294                 }
 295         }
 296
 297         /* types */
 298         myset = get_type_map(tp, d_up);
 299         for (i = 0; i < n_supertypes; ++i) {
 300                 ir_type *stp = get_class_supertype(tp, i);
 301                 subset = get_type_map(stp, d_up);
 302                 pset_insert_ptr(myset, stp);
 303                 pset_insert_pset_ptr(myset, subset);
 304         }
 305
 306         /* entities */
 307         n_members = get_class_n_members(tp);
 308         for (i = 0; i < n_members; ++i) {
 309                 ir_entity *mem = get_class_member(tp, i);
 310                 size_t j, n_overwrites = get_entity_n_overwrites(mem);
 311
 312                 myset = get_entity_map(mem, d_up);
 313                 for (j = 0; j < n_overwrites; ++j) {
 314                         ir_entity *ov = get_entity_overwrites(mem, j);
 315                         subset = get_entity_map(ov, d_up);
 316                         pset_insert_pset_ptr(myset, subset);
 317                         pset_insert_ptr(myset, ov);
 318                 }
 319         }
 320
 321         mark_type_visited(tp);
 322
 323         /* Walk down. */
 324         n_subtypes = get_class_n_subtypes(tp);
 325         for (i = 0; i < n_subtypes; ++i) {
 326                 ir_type *stp = get_class_subtype(tp, i);
 327                 if (get_type_visited(stp) < master_visited-1) {
 328                         compute_up_closure(stp);
 329                 }
 330         }
 331 }
 332
 333 void compute_inh_transitive_closure(void)
 334 {
 335         size_t i, n_types = get_irp_n_types();
 336         free_inh_transitive_closure();
 337
 338         /* The 'down' relation */
 339         irp_reserve_resources(irp, IRP_RESOURCE_TYPE_VISITED);
 340         inc_master_type_visited();  /* Inc twice: one if on stack, second if values computed. */
 341         inc_master_type_visited();
 342         for (i = 0; i < n_types; ++i) {
 343                 ir_type *tp = get_irp_type(i);
 344                 if (is_Class_type(tp) && type_not_visited(tp)) { /* For others there is nothing to accumulate. */
 345                         size_t j, n_subtypes = get_class_n_subtypes(tp);
 346                         int has_unmarked_subtype = 0;
 347
 348                         assert(get_type_visited(tp) < get_master_type_visited()-1);
 349                         for (j = 0; j < n_subtypes; ++j) {
 350                                 ir_type *stp = get_class_subtype(tp, j);
 351                                 if (type_not_visited(stp)) {
 352                                         has_unmarked_subtype = 1;
 353                                         break;
 354                                 }
 355                         }
 356
 357                         /* This is a good starting point. */
 358                         if (!has_unmarked_subtype)
 359                                 compute_down_closure(tp);
 360                 }
 361         }
 362
 363         /* The 'up' relation */
 364         inc_master_type_visited();
 365         inc_master_type_visited();
 366         for (i = 0; i < n_types; ++i) {
 367                 ir_type *tp = get_irp_type(i);
 368                 if (is_Class_type(tp) && type_not_visited(tp)) { /* For others there is nothing to accumulate. */
 369                         size_t j, n_supertypes = get_class_n_supertypes(tp);
 370                         int has_unmarked_supertype = 0;
 371
 372                         assert(get_type_visited(tp) < get_master_type_visited()-1);
 373                         for (j = 0; j < n_supertypes; ++j) {
 374                                 ir_type *stp = get_class_supertype(tp, j);
 375                                 if (type_not_visited(stp)) {
 376                                         has_unmarked_supertype = 1;
 377                                         break;
 378                                 }
 379                         }
 380
 381                         /* This is a good starting point. */
 382                         if (!has_unmarked_supertype)
 383                                 compute_up_closure(tp);
 384                 }
 385         }
 386
 387         irp->inh_trans_closure_state = inh_transitive_closure_valid;
 388         irp_free_resources(irp, IRP_RESOURCE_TYPE_VISITED);
 389 }
 390
 391 void free_inh_transitive_closure(void)
 392 {
 393         if (tr_inh_trans_set) {
 394                 foreach_set(tr_inh_trans_set, tr_inh_trans_tp, elt) {
 395                         del_pset(elt->directions[d_up]);
 396                         del_pset(elt->directions[d_down]);
 397                 }
 398                 del_set(tr_inh_trans_set);
 399                 tr_inh_trans_set = NULL;
 400         }
 401         irp->inh_trans_closure_state = inh_transitive_closure_none;
 402 }
 403
 404 /* - subtype ------------------------------------------------------------- */
 405
 406 ir_type *get_class_trans_subtype_first(const ir_type *tp)
 407 {
 408         assert_valid_state();
 409         return pset_first(ir_type, get_type_map(tp, d_down));
 410 }
 411
 412 ir_type *get_class_trans_subtype_next(const ir_type *tp)
 413 {
 414         assert_valid_state();
 415         return pset_next(ir_type, get_type_map(tp, d_down));
 416 }
 417
 418 int is_class_trans_subtype(const ir_type *tp, const ir_type *subtp)
 419 {
 420         assert_valid_state();
 421         return (pset_find_ptr(get_type_map(tp, d_down), subtp) != NULL);
 422 }
 423
 424 /* - supertype ----------------------------------------------------------- */
 425
 426 ir_type *get_class_trans_supertype_first(const ir_type *tp)
 427 {
 428         assert_valid_state();
 429         return pset_first(ir_type, get_type_map(tp, d_up));
 430 }
 431
 432 ir_type *get_class_trans_supertype_next(const ir_type *tp)
 433 {
 434         assert_valid_state();
 435         return pset_next(ir_type, get_type_map(tp, d_up));
 436 }
 437
 438 /* - overwrittenby ------------------------------------------------------- */
 439
 440 ir_entity *get_entity_trans_overwrittenby_first(const ir_entity *ent)
 441 {
 442         assert_valid_state();
 443         return pset_first(ir_entity, get_entity_map(ent, d_down));
 444 }
 445
 446 ir_entity *get_entity_trans_overwrittenby_next(const ir_entity *ent)
 447 {
 448         assert_valid_state();
 449         return pset_next(ir_entity, get_entity_map(ent, d_down));
 450 }
 451
 452 /* - overwrites ---------------------------------------------------------- */
 453
 454
 455 ir_entity *get_entity_trans_overwrites_first(const ir_entity *ent)
 456 {
 457         assert_valid_state();
 458         return pset_first(ir_entity, get_entity_map(ent, d_up));
 459 }
 460
 461 ir_entity *get_entity_trans_overwrites_next(const ir_entity *ent)
 462 {
 463         assert_valid_state();
 464         return pset_next(ir_entity, get_entity_map(ent, d_up));
 465 }
 466
 467
 468 /* ----------------------------------------------------------------------- */
 469 /* Classify pairs of types/entities in the inheritance relations.          */
 470 /* ----------------------------------------------------------------------- */
 471
 472 /** Returns true if low is subclass of high. */
 473 static int check_is_SubClass_of(ir_type *low, ir_type *high)
 474 {
 475         size_t i, n_subtypes;
 476
 477         /* depth first search from high downwards. */
 478         n_subtypes = get_class_n_subtypes(high);
 479         for (i = 0; i < n_subtypes; i++) {
 480                 ir_type *stp = get_class_subtype(high, i);
 481                 if (low == stp) return 1;
 482                 if (is_SubClass_of(low, stp))
 483                         return 1;
 484         }
 485         return 0;
 486 }
 487
 488 int is_SubClass_of(ir_type *low, ir_type *high)
 489 {
 490         assert(is_Class_type(low) && is_Class_type(high));
 491
 492         if (low == high) return 1;
 493
 494         if (get_irp_inh_transitive_closure_state() == inh_transitive_closure_valid) {
 495                 pset *m = get_type_map(high, d_down);
 496                 return pset_find_ptr(m, low) ? 1 : 0;
 497         }
 498         return check_is_SubClass_of(low, high);
 499 }
 500
 501 int is_SubClass_ptr_of(ir_type *low, ir_type *high)
 502 {
 503         while (is_Pointer_type(low) && is_Pointer_type(high)) {
 504                 low  = get_pointer_points_to_type(low);
 505                 high = get_pointer_points_to_type(high);
 506         }
 507
 508         if (is_Class_type(low) && is_Class_type(high))
 509                 return is_SubClass_of(low, high);
 510         return 0;
 511 }
 512
 513 int is_overwritten_by(ir_entity *high, ir_entity *low)
 514 {
 515         size_t i, n_overwrittenby;
 516         assert(is_entity(low) && is_entity(high));
 517
 518         if (get_irp_inh_transitive_closure_state() == inh_transitive_closure_valid) {
 519                 pset *m = get_entity_map(high, d_down);
 520                 return pset_find_ptr(m, low) ? 1 : 0;
 521         }
 522
 523         /* depth first search from high downwards. */
 524         n_overwrittenby = get_entity_n_overwrittenby(high);
 525         for (i = 0; i < n_overwrittenby; i++) {
 526                 ir_entity *ov = get_entity_overwrittenby(high, i);
 527                 if (low == ov) return 1;
 528                 if (is_overwritten_by(low, ov))
 529                         return 1;
 530         }
 531         return 0;
 532 }
 533
 534 /** Resolve polymorphy in the inheritance relation.
 535  *
 536  * Returns the dynamically referenced entity if the static entity and the
 537  * dynamic type are given.
 538  * Search downwards in overwritten tree.
 539  *
 540  * Need two routines because I want to assert the result.
 541  */
 542 static ir_entity *do_resolve_ent_polymorphy(ir_type *dynamic_class, ir_entity *static_ent)
 543 {
 544         size_t i, n_overwrittenby;
 545
 546         ir_type *owner = get_entity_owner(static_ent);
 547         if (owner == dynamic_class) return static_ent;
 548
 549         // if the owner of the static_ent already is more special than the dynamic
 550         // type to check against - stop here.
 551         if (! is_SubClass_of(dynamic_class, owner)) return NULL;
 552
 553         n_overwrittenby = get_entity_n_overwrittenby(static_ent);
 554         for (i = 0; i < n_overwrittenby; ++i) {
 555                 ir_entity *ent = get_entity_overwrittenby(static_ent, i);
 556                 ent = do_resolve_ent_polymorphy(dynamic_class, ent);
 557                 if (ent) return ent;
 558         }
 559
 560         // No further specialization of static_ent has been found
 561         return static_ent;
 562 }
 563
 564 ir_entity *resolve_ent_polymorphy(ir_type *dynamic_class, ir_entity *static_ent)
 565 {
 566         ir_entity *res;
 567         assert(static_ent && is_entity(static_ent));
 568
 569         res = do_resolve_ent_polymorphy(dynamic_class, static_ent);
 570         assert(res);
 571
 572         return res;
 573 }
 574
 575
 576
 577 /* ----------------------------------------------------------------------- */
 578 /* Class cast state handling.                                              */
 579 /* ----------------------------------------------------------------------- */
 580
 581 /* - State handling. ----------------------------------------- */
 582
 583 void set_irg_class_cast_state(ir_graph *irg, ir_class_cast_state s)
 584 {
 585         if (get_irp_class_cast_state() > s)
 586                 set_irp_class_cast_state(s);
 587         irg->class_cast_state = s;
 588 }
 589
 590 ir_class_cast_state get_irg_class_cast_state(const ir_graph *irg)
 591 {
 592         return irg->class_cast_state;
 593 }
 594
 595 void set_irp_class_cast_state(ir_class_cast_state s)
 596 {
 597 #ifndef NDEBUG
 598         size_t i, n;
 599         for (i = 0, n = get_irp_n_irgs(); i < n; ++i)
 600                 assert(get_irg_class_cast_state(get_irp_irg(i)) >= s);
 601 #endif
 602         irp->class_cast_state = s;
 603 }
 604
 605 ir_class_cast_state get_irp_class_cast_state(void)
 606 {
 607         return irp->class_cast_state;
 608 }