nsz Git - libfirm/blob - ir/tr/tr_inheritance.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  * @file    tr_inheritance.c
  22  * @brief   Utility routines for inheritance representation
  23  * @author  Goetz Lindenmaier
  24  * @version $Id$
  25  */
  26 #include "config.h"
  27
  28 #include "debug.h"
  29 #include "typerep.h"
  30 #include "irgraph_t.h"
  31 #include "irprog_t.h"
  32 #include "irprintf.h"
  33 #include "pset.h"
  34 #include "set.h"
  35 #include "irgwalk.h"
  36 #include "irflag.h"
  37
  38 DEBUG_ONLY(static firm_dbg_module_t *dbg);
  39
  40 /* ----------------------------------------------------------------------- */
  41 /* Resolve implicit inheritance.                                           */
  42 /* ----------------------------------------------------------------------- */
  43
  44 ident *default_mangle_inherited_name(const ir_entity *super, const ir_type *clss)
  45 {
  46         return id_mangle_u(new_id_from_str("inh"), id_mangle_u(get_class_ident(clss), get_entity_ident(super)));
  47 }
  48
  49 /** Replicates all entities in all super classes that are not overwritten
  50     by an entity of this class. */
  51 static void copy_entities_from_superclass(ir_type *clss, void *env)
  52 {
  53         int i, j, k, l;
  54         int overwritten;
  55         ir_type *super, *inhenttype;
  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                 assert(is_Class_type(super) && "not a class");
  62                 for (j = 0; j < get_class_n_members(super); j++) {
  63                         inhent = get_class_member(super, j);
  64                         inhenttype = get_entity_type(inhent);
  65                         /* check whether inhent is already overwritten */
  66                         overwritten = 0;
  67                         for (k = 0; (k < get_class_n_members(clss)) && (overwritten == 0); k++) {
  68                                 thisent = get_class_member(clss, k);
  69                                 for (l = 0; l < get_entity_n_overwrites(thisent); l++) {
  70                                         if (inhent == get_entity_overwrites(thisent, l)) {
  71                                                 /* overwritten - do not copy */
  72                                                 overwritten = 1;
  73                                                 break;
  74                                         }
  75                                 }
  76                         }
  77                         /* Inherit entity */
  78                         if (!overwritten) {
  79                                 thisent = copy_entity_own(inhent, clss);
  80                                 add_entity_overwrites(thisent, inhent);
  81                                 if (get_entity_peculiarity(inhent) == peculiarity_existent)
  82                                         set_entity_peculiarity(thisent, peculiarity_inherited);
  83                                 set_entity_ld_ident(thisent, mfunc(inhent, clss));
  84                                 if (get_entity_linkage(inhent) & IR_LINKAGE_CONSTANT) {
  85                                         assert(is_atomic_entity(inhent) &&  /* @@@ */
  86                                                 "Inheritance of constant, compound entities not implemented");
  87                                         add_entity_linkage(thisent, IR_LINKAGE_CONSTANT);
  88                                         set_atomic_ent_value(thisent, get_atomic_ent_value(inhent));
  89                                 }
  90                         }
  91                 }
  92         }
  93 }
  94
  95 /* Resolve implicit inheritance.
  96  *
  97  *  Resolves the implicit inheritance supplied by firm.
  98  */
  99 void resolve_inheritance(mangle_inherited_name_func *mfunc)
 100 {
 101         if (!mfunc)
 102                 mfunc = default_mangle_inherited_name;
 103         class_walk_super2sub(copy_entities_from_superclass, NULL, (void *)&mfunc);
 104 }
 105
 106
 107 /* ----------------------------------------------------------------------- */
 108 /* The transitive closure of the subclass/superclass and                   */
 109 /* overwrites/overwrittenby relation.                                      */
 110 /*                                                                         */
 111 /* A walk over the ir (O(#types+#entities)) computes the transitive        */
 112 /* closure.  Adding a new type/entity or changing the basic relations in   */
 113 /* some other way invalidates the transitive closure, i.e., it is not      */
 114 /* updated by the basic functions.                                         */
 115 /*                                                                         */
 116 /* All functions are named as their counterparts for the basic relations,  */
 117 /* adding the infix 'trans_'.                                              */
 118 /* ----------------------------------------------------------------------- */
 119
 120 void                        set_irp_inh_transitive_closure_state(inh_transitive_closure_state s)
 121 {
 122         irp->inh_trans_closure_state = s;
 123 }
 124 void                        invalidate_irp_inh_transitive_closure_state(void)
 125 {
 126         if (irp->inh_trans_closure_state == inh_transitive_closure_valid)
 127                 irp->inh_trans_closure_state = inh_transitive_closure_invalid;
 128 }
 129 inh_transitive_closure_state get_irp_inh_transitive_closure_state(void)
 130 {
 131         return irp->inh_trans_closure_state;
 132 }
 133
 134 static void assert_valid_state(void)
 135 {
 136         assert(irp->inh_trans_closure_state == inh_transitive_closure_valid ||
 137                irp->inh_trans_closure_state == inh_transitive_closure_invalid);
 138 }
 139
 140 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
 141 /* There is a set that extends each entity/type with two new               */
 142 /* fields:  one for the upwards directed relation: 'up' (supertype,        */
 143 /* overwrites) and one for the downwards directed relation: 'down' (sub-   */
 144 /* type, overwrittenby.  These fields contain psets (and maybe later       */
 145 /* arrays) listing all subtypes...                                         */
 146 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
 147
 148 typedef enum {
 149         d_up   = 0,
 150         d_down = 1,
 151 } dir;
 152
 153 typedef struct {
 154         const firm_kind *kind;   /**< An entity or type. */
 155         pset *directions[2];
 156 } tr_inh_trans_tp;
 157
 158 /* We use this set for all types and entities.  */
 159 static set *tr_inh_trans_set = NULL;
 160
 161 /**
 162  * Compare two tr_inh_trans_tp entries.
 163  */
 164 static int tr_inh_trans_cmp(const void *e1, const void *e2, size_t size)
 165 {
 166         const tr_inh_trans_tp *ef1 = (const tr_inh_trans_tp*)e1;
 167         const tr_inh_trans_tp *ef2 = (const tr_inh_trans_tp*)e2;
 168         (void) size;
 169
 170         return ef1->kind != ef2->kind;
 171 }
 172
 173 /**
 174  * calculate the hash value of an tr_inh_trans_tp
 175  */
 176 static inline unsigned int tr_inh_trans_hash(const tr_inh_trans_tp *v)
 177 {
 178         return HASH_PTR(v->kind);
 179 }
 180
 181 /* This always completes successfully. */
 182 static tr_inh_trans_tp *get_firm_kind_entry(const firm_kind *k)
 183 {
 184         tr_inh_trans_tp a, *found;
 185         a.kind = k;
 186
 187         if (!tr_inh_trans_set) tr_inh_trans_set = new_set(tr_inh_trans_cmp, 128);
 188
 189         found = (tr_inh_trans_tp*)set_find(tr_inh_trans_set, &a, sizeof(a), tr_inh_trans_hash(&a));
 190         if (!found) {
 191                 a.directions[d_up]   = pset_new_ptr(16);
 192                 a.directions[d_down] = pset_new_ptr(16);
 193                 found = (tr_inh_trans_tp*)set_insert(tr_inh_trans_set, &a, sizeof(a), tr_inh_trans_hash(&a));
 194         }
 195         return found;
 196 }
 197
 198 static pset *get_entity_map(const ir_entity *ent, dir d)
 199 {
 200         tr_inh_trans_tp *found;
 201
 202         assert(is_entity(ent));
 203         found = get_firm_kind_entry((const firm_kind *)ent);
 204         return found->directions[d];
 205 }
 206
 207 static pset *get_type_map(const ir_type *tp, dir d)
 208 {
 209         tr_inh_trans_tp *found;
 210
 211         assert(is_type(tp));
 212         found = get_firm_kind_entry((const firm_kind *)tp);
 213         return found->directions[d];
 214 }
 215
 216
 217 /**
 218  * Walk over all types reachable from tp in the sub/supertype
 219  * relation and compute the closure for the two downwards directed
 220  * relations.
 221  *
 222  * The walk in the dag formed by the relation is tricky:  We must visit
 223  * all subtypes before visiting the supertypes.  So we first walk down.
 224  * Then we can compute the closure for this type.  Then we walk up.
 225  * As we call ourselves recursive, and walk in both directions, there
 226  * can be cycles.  So we have to make sure, that if we visit a node
 227  * a second time (in a walk up) we do nothing.  For this we increment
 228  * the master visited flag twice.
 229  * If the type is marked with master_flag_visited-1 it is on the stack.
 230  * If it is marked with master_flag_visited it is fully processed.
 231  *
 232  * Well, we still miss some candidates ... */
 233 static void compute_down_closure(ir_type *tp)
 234 {
 235         pset *myset, *subset;
 236         int i, n_subtypes, n_members, n_supertypes;
 237         ir_visited_t master_visited = get_master_type_visited();
 238
 239         assert(is_Class_type(tp));
 240
 241         set_type_visited(tp, master_visited-1);
 242
 243         /* Recursive descend. */
 244         n_subtypes = get_class_n_subtypes(tp);
 245         for (i = 0; i < n_subtypes; ++i) {
 246                 ir_type *stp = get_class_subtype(tp, i);
 247                 if (get_type_visited(stp) < master_visited-1) {
 248                         compute_down_closure(stp);
 249                 }
 250         }
 251
 252         /* types */
 253         myset = get_type_map(tp, d_down);
 254         for (i = 0; i < n_subtypes; ++i) {
 255                 ir_type *stp = get_class_subtype(tp, i);
 256                 subset = get_type_map(stp, d_down);
 257                 pset_insert_ptr(myset, stp);
 258                 pset_insert_pset_ptr(myset, subset);
 259         }
 260
 261         /* entities */
 262         n_members = get_class_n_members(tp);
 263         for (i = 0; i < n_members; ++i) {
 264                 ir_entity *mem = get_class_member(tp, i);
 265                 int j, n_overwrittenby = get_entity_n_overwrittenby(mem);
 266
 267                 myset = get_entity_map(mem, d_down);
 268                 for (j = 0; j < n_overwrittenby; ++j) {
 269                         ir_entity *ov = get_entity_overwrittenby(mem, j);
 270                         subset = get_entity_map(ov, d_down);
 271                         pset_insert_ptr(myset, ov);
 272                         pset_insert_pset_ptr(myset, subset);
 273                 }
 274         }
 275
 276         mark_type_visited(tp);
 277
 278         /* Walk up. */
 279         n_supertypes = get_class_n_supertypes(tp);
 280         for (i = 0; i < n_supertypes; ++i) {
 281                 ir_type *stp = get_class_supertype(tp, i);
 282                 if (get_type_visited(stp) < master_visited-1) {
 283                         compute_down_closure(stp);
 284                 }
 285         }
 286 }
 287
 288 static void compute_up_closure(ir_type *tp)
 289 {
 290         pset *myset, *subset;
 291         int i, n_subtypes, n_members, n_supertypes;
 292         ir_visited_t master_visited = get_master_type_visited();
 293
 294         assert(is_Class_type(tp));
 295
 296         set_type_visited(tp, master_visited-1);
 297
 298         /* Recursive descend. */
 299         n_supertypes = get_class_n_supertypes(tp);
 300         for (i = 0; i < n_supertypes; ++i) {
 301                 ir_type *stp = get_class_supertype(tp, i);
 302                 if (get_type_visited(stp) < get_master_type_visited()-1) {
 303                         compute_up_closure(stp);
 304                 }
 305         }
 306
 307         /* types */
 308         myset = get_type_map(tp, d_up);
 309         for (i = 0; i < n_supertypes; ++i) {
 310                 ir_type *stp = get_class_supertype(tp, i);
 311                 subset = get_type_map(stp, d_up);
 312                 pset_insert_ptr(myset, stp);
 313                 pset_insert_pset_ptr(myset, subset);
 314         }
 315
 316         /* entities */
 317         n_members = get_class_n_members(tp);
 318         for (i = 0; i < n_members; ++i) {
 319                 ir_entity *mem = get_class_member(tp, i);
 320                 int j, n_overwrites = get_entity_n_overwrites(mem);
 321
 322                 myset = get_entity_map(mem, d_up);
 323                 for (j = 0; j < n_overwrites; ++j) {
 324                         ir_entity *ov = get_entity_overwrites(mem, j);
 325                         subset = get_entity_map(ov, d_up);
 326                         pset_insert_pset_ptr(myset, subset);
 327                         pset_insert_ptr(myset, ov);
 328                 }
 329         }
 330
 331         mark_type_visited(tp);
 332
 333         /* Walk down. */
 334         n_subtypes = get_class_n_subtypes(tp);
 335         for (i = 0; i < n_subtypes; ++i) {
 336                 ir_type *stp = get_class_subtype(tp, i);
 337                 if (get_type_visited(stp) < master_visited-1) {
 338                         compute_up_closure(stp);
 339                 }
 340         }
 341 }
 342
 343 /** Compute the transitive closure of the subclass/superclass and
 344  *  overwrites/overwrittenby relation.
 345  *
 346  *  This function walks over the ir (O(#types+#entities)) to compute the
 347  *  transitive closure.    */
 348 void compute_inh_transitive_closure(void)
 349 {
 350         int i, n_types = get_irp_n_types();
 351         free_inh_transitive_closure();
 352
 353         /* The 'down' relation */
 354         irp_reserve_resources(irp, IR_RESOURCE_TYPE_VISITED);
 355         inc_master_type_visited();  /* Inc twice: one if on stack, second if values computed. */
 356         inc_master_type_visited();
 357         for (i = 0; i < n_types; ++i) {
 358                 ir_type *tp = get_irp_type(i);
 359                 if (is_Class_type(tp) && type_not_visited(tp)) { /* For others there is nothing to accumulate. */
 360                         int j, n_subtypes = get_class_n_subtypes(tp);
 361                         int has_unmarked_subtype = 0;
 362
 363                         assert(get_type_visited(tp) < get_master_type_visited()-1);
 364                         for (j = 0; j < n_subtypes; ++j) {
 365                                 ir_type *stp = get_class_subtype(tp, j);
 366                                 if (type_not_visited(stp)) {
 367                                         has_unmarked_subtype = 1;
 368                                         break;
 369                                 }
 370                         }
 371
 372                         /* This is a good starting point. */
 373                         if (!has_unmarked_subtype)
 374                                 compute_down_closure(tp);
 375                 }
 376         }
 377
 378         /* The 'up' relation */
 379         inc_master_type_visited();
 380         inc_master_type_visited();
 381         for (i = 0; i < n_types; ++i) {
 382                 ir_type *tp = get_irp_type(i);
 383                 if (is_Class_type(tp) && type_not_visited(tp)) { /* For others there is nothing to accumulate. */
 384                         int j, n_supertypes = get_class_n_supertypes(tp);
 385                         int has_unmarked_supertype = 0;
 386
 387                         assert(get_type_visited(tp) < get_master_type_visited()-1);
 388                         for (j = 0; j < n_supertypes; ++j) {
 389                                 ir_type *stp = get_class_supertype(tp, j);
 390                                 if (type_not_visited(stp)) {
 391                                         has_unmarked_supertype = 1;
 392                                         break;
 393                                 }
 394                         }
 395
 396                         /* This is a good starting point. */
 397                         if (!has_unmarked_supertype)
 398                                 compute_up_closure(tp);
 399                 }
 400         }
 401
 402         irp->inh_trans_closure_state = inh_transitive_closure_valid;
 403         irp_free_resources(irp, IR_RESOURCE_TYPE_VISITED);
 404 }
 405
 406 /** Free memory occupied by the transitive closure information. */
 407 void free_inh_transitive_closure(void)
 408 {
 409         if (tr_inh_trans_set) {
 410                 tr_inh_trans_tp *elt;
 411                 for (elt = (tr_inh_trans_tp*)set_first(tr_inh_trans_set); elt != NULL;
 412                      elt = (tr_inh_trans_tp*)set_next(tr_inh_trans_set)) {
 413                         del_pset(elt->directions[d_up]);
 414                         del_pset(elt->directions[d_down]);
 415                 }
 416                 del_set(tr_inh_trans_set);
 417                 tr_inh_trans_set = NULL;
 418         }
 419         irp->inh_trans_closure_state = inh_transitive_closure_none;
 420 }
 421
 422 /* - subtype ------------------------------------------------------------- */
 423
 424 ir_type *get_class_trans_subtype_first(const ir_type *tp)
 425 {
 426         assert_valid_state();
 427         return (ir_type*)pset_first(get_type_map(tp, d_down));
 428 }
 429
 430 ir_type *get_class_trans_subtype_next(const ir_type *tp)
 431 {
 432         assert_valid_state();
 433         return (ir_type*)pset_next(get_type_map(tp, d_down));
 434 }
 435
 436 int is_class_trans_subtype(const ir_type *tp, const ir_type *subtp)
 437 {
 438         assert_valid_state();
 439         return (pset_find_ptr(get_type_map(tp, d_down), subtp) != NULL);
 440 }
 441
 442 /* - supertype ----------------------------------------------------------- */
 443
 444 ir_type *get_class_trans_supertype_first(const ir_type *tp)
 445 {
 446         assert_valid_state();
 447         return (ir_type*)pset_first(get_type_map(tp, d_up));
 448 }
 449
 450 ir_type *get_class_trans_supertype_next(const ir_type *tp)
 451 {
 452         assert_valid_state();
 453         return (ir_type*)pset_next(get_type_map(tp, d_up));
 454 }
 455
 456 /* - overwrittenby ------------------------------------------------------- */
 457
 458 ir_entity *get_entity_trans_overwrittenby_first(const ir_entity *ent)
 459 {
 460         assert_valid_state();
 461         return (ir_entity*)pset_first(get_entity_map(ent, d_down));
 462 }
 463
 464 ir_entity *get_entity_trans_overwrittenby_next(const ir_entity *ent)
 465 {
 466         assert_valid_state();
 467         return (ir_entity*)pset_next(get_entity_map(ent, d_down));
 468 }
 469
 470 /* - overwrites ---------------------------------------------------------- */
 471
 472
 473 /** Iterate over all transitive overwritten entities. */
 474 ir_entity *get_entity_trans_overwrites_first(const ir_entity *ent)
 475 {
 476         assert_valid_state();
 477         return (ir_entity*)pset_first(get_entity_map(ent, d_up));
 478 }
 479
 480 ir_entity *get_entity_trans_overwrites_next(const ir_entity *ent)
 481 {
 482         assert_valid_state();
 483         return (ir_entity*)pset_next(get_entity_map(ent, d_up));
 484 }
 485
 486
 487 /* ----------------------------------------------------------------------- */
 488 /* Classify pairs of types/entities in the inheritance relations.          */
 489 /* ----------------------------------------------------------------------- */
 490
 491 /** Returns true if low is subclass of high. */
 492 static int check_is_SubClass_of(ir_type *low, ir_type *high)
 493 {
 494         int i, n_subtypes;
 495
 496         /* depth first search from high downwards. */
 497         n_subtypes = get_class_n_subtypes(high);
 498         for (i = 0; i < n_subtypes; i++) {
 499                 ir_type *stp = get_class_subtype(high, i);
 500                 if (low == stp) return 1;
 501                 if (is_SubClass_of(low, stp))
 502                         return 1;
 503         }
 504         return 0;
 505 }
 506
 507 /* Returns true if low is subclass of high. */
 508 int is_SubClass_of(ir_type *low, ir_type *high)
 509 {
 510         assert(is_Class_type(low) && is_Class_type(high));
 511
 512         if (low == high) return 1;
 513
 514         if (get_irp_inh_transitive_closure_state() == inh_transitive_closure_valid) {
 515                 pset *m = get_type_map(high, d_down);
 516                 return pset_find_ptr(m, low) ? 1 : 0;
 517         }
 518         return check_is_SubClass_of(low, high);
 519 }
 520
 521
 522 /* Subclass check for pointers to classes.
 523  *
 524  *  Dereferences at both types the same amount of pointer types (as
 525  *  many as possible).  If the remaining types are both class types
 526  *  and subclasses, returns true, else false.  Can also be called with
 527  *  two class types.  */
 528 int is_SubClass_ptr_of(ir_type *low, ir_type *high)
 529 {
 530         while (is_Pointer_type(low) && is_Pointer_type(high)) {
 531                 low  = get_pointer_points_to_type(low);
 532                 high = get_pointer_points_to_type(high);
 533         }
 534
 535         if (is_Class_type(low) && is_Class_type(high))
 536                 return is_SubClass_of(low, high);
 537         return 0;
 538 }
 539
 540 int is_overwritten_by(ir_entity *high, ir_entity *low)
 541 {
 542         int i, n_overwrittenby;
 543         assert(is_entity(low) && is_entity(high));
 544
 545         if (get_irp_inh_transitive_closure_state() == inh_transitive_closure_valid) {
 546                 pset *m = get_entity_map(high, d_down);
 547                 return pset_find_ptr(m, low) ? 1 : 0;
 548         }
 549
 550         /* depth first search from high downwards. */
 551         n_overwrittenby = get_entity_n_overwrittenby(high);
 552         for (i = 0; i < n_overwrittenby; i++) {
 553                 ir_entity *ov = get_entity_overwrittenby(high, i);
 554                 if (low == ov) return 1;
 555                 if (is_overwritten_by(low, ov))
 556                         return 1;
 557         }
 558         return 0;
 559 }
 560
 561 /** Resolve polymorphy in the inheritance relation.
 562  *
 563  * Returns the dynamically referenced entity if the static entity and the
 564  * dynamic type are given.
 565  * Search downwards in overwritten tree.
 566  *
 567  * Need two routines because I want to assert the result.
 568  */
 569 static ir_entity *do_resolve_ent_polymorphy(ir_type *dynamic_class, ir_entity *static_ent)
 570 {
 571         int i, n_overwrittenby;
 572
 573         if (get_entity_owner(static_ent) == dynamic_class) return static_ent;
 574
 575         n_overwrittenby = get_entity_n_overwrittenby(static_ent);
 576         for (i = 0; i < n_overwrittenby; ++i) {
 577                 ir_entity *ent = get_entity_overwrittenby(static_ent, i);
 578                 ent = do_resolve_ent_polymorphy(dynamic_class, ent);
 579                 if (ent) return ent;
 580         }
 581         return NULL;
 582 }
 583
 584 /* Resolve polymorphy in the inheritance relation.
 585  *
 586  * Returns the dynamically referenced entity if the static entity and the
 587  * dynamic type are given.
 588  * Search downwards in overwritten tree.
 589  */
 590 ir_entity *resolve_ent_polymorphy(ir_type *dynamic_class, ir_entity *static_ent)
 591 {
 592         ir_entity *res;
 593         assert(static_ent && is_entity(static_ent));
 594
 595         res = do_resolve_ent_polymorphy(dynamic_class, static_ent);
 596         assert(res);
 597
 598         return res;
 599 }
 600
 601
 602
 603 /* ----------------------------------------------------------------------- */
 604 /* Class cast state handling.                                              */
 605 /* ----------------------------------------------------------------------- */
 606
 607 /* - State handling. ----------------------------------------- */
 608
 609 void set_irg_class_cast_state(ir_graph *irg, ir_class_cast_state s)
 610 {
 611         if (get_irp_class_cast_state() > s)
 612                 set_irp_class_cast_state(s);
 613         irg->class_cast_state = s;
 614 }
 615
 616 ir_class_cast_state get_irg_class_cast_state(const ir_graph *irg)
 617 {
 618         return irg->class_cast_state;
 619 }
 620
 621 void set_irp_class_cast_state(ir_class_cast_state s)
 622 {
 623 #ifndef NDEBUG
 624         int i;
 625         for (i = get_irp_n_irgs() - 1; i >= 0; --i)
 626                 assert(get_irg_class_cast_state(get_irp_irg(i)) >= s);
 627 #endif
 628         irp->class_cast_state = s;
 629 }
 630
 631 ir_class_cast_state get_irp_class_cast_state(void)
 632 {
 633         return irp->class_cast_state;
 634 }
 635
 636 const char *get_class_cast_state_string(ir_class_cast_state s)
 637 {
 638 #define X(a)    case a: return #a
 639         switch (s) {
 640         X(ir_class_casts_any);
 641         X(ir_class_casts_transitive);
 642         X(ir_class_casts_normalized);
 643         X(ir_class_casts_state_max);
 644         default: return "invalid class cast state";
 645         }
 646 #undef X
 647 }
 648
 649 /* - State verification. ------------------------------------- */
 650
 651 typedef struct ccs_env {
 652         ir_class_cast_state expected_state;
 653         ir_class_cast_state worst_situation;
 654 } ccs_env;
 655
 656 /**
 657  * Walker: check Casts.
 658  */
 659 static void verify_irn_class_cast_state(ir_node *n, void *env)
 660 {
 661         ccs_env             *ccs = (ccs_env *)env;
 662         ir_class_cast_state this_state = ir_class_casts_any;
 663         ir_type             *fromtype, *totype;
 664         int                 ref_depth = 0;
 665
 666         if (!is_Cast(n)) return;
 667
 668         fromtype = get_irn_typeinfo_type(get_Cast_op(n));
 669         totype   = get_Cast_type(n);
 670
 671         while (is_Pointer_type(totype) && is_Pointer_type(fromtype)) {
 672                 totype   = get_pointer_points_to_type(totype);
 673                 fromtype = get_pointer_points_to_type(fromtype);
 674                 ref_depth++;
 675         }
 676
 677         if (!is_Class_type(totype)) return;
 678
 679         if (is_SubClass_of(totype, fromtype) ||
 680                 is_SubClass_of(fromtype, totype)   ) {
 681                 this_state = ir_class_casts_transitive;
 682                 if ((get_class_supertype_index(totype, fromtype) != -1) ||
 683                     (get_class_supertype_index(fromtype, totype) != -1) ||
 684                     fromtype == totype) {
 685                         /*   Das ist doch alt?  Aus dem cvs aufgetaucht ...
 686                         if ((get_class_supertype_index(totype, fromtype) == -1) &&
 687                             (get_class_supertype_index(fromtype, totype) == -1) ) {  */
 688                         this_state = ir_class_casts_normalized;
 689                 }
 690         }
 691
 692         if (!(this_state >= ccs->expected_state)) {
 693                 ir_printf("  Node is %+F\n", n);
 694                 ir_printf("    totype   %+F\n", totype);
 695                 ir_printf("    fromtype %+F\n", fromtype);
 696                 ir_printf("    this_state: %s, exp. state: %s\n",
 697                         get_class_cast_state_string(this_state),
 698                         get_class_cast_state_string(ccs->expected_state));
 699                 assert(this_state >= ccs->expected_state &&
 700                         "invalid state class cast state setting in graph");
 701         }
 702
 703         if (this_state < ccs->worst_situation)
 704                 ccs->worst_situation = this_state;
 705 }
 706
 707 /** Verify that the graph meets requirements of state set. */
 708 void verify_irg_class_cast_state(ir_graph *irg)
 709 {
 710         ccs_env env;
 711
 712         FIRM_DBG_REGISTER(dbg, "firm.tr.inheritance");
 713
 714         env.expected_state  = get_irg_class_cast_state(irg);
 715         env.worst_situation = ir_class_casts_normalized;
 716
 717         irg_walk_graph(irg, NULL, verify_irn_class_cast_state, &env);
 718
 719         if ((env.worst_situation > env.expected_state)) {
 720                 DB((dbg, LEVEL_1, "Note:  class cast state is set lower than reqired "
 721                     "in graph \n\t%+F\n", irg));
 722                 DB((dbg, LEVEL_1, "       state is %s, reqired is %s\n",
 723                         get_class_cast_state_string(env.expected_state),
 724                         get_class_cast_state_string(env.worst_situation)));
 725         }
 726 }