nsz Git - libfirm/blob - ir/tr/tr_inheritance.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  * @file    tr_inheritance.c
  22  * @brief   Utility routines for inheritance representation
  23  * @author  Goetz Lindenmaier
  24  * @version $Id$
  25  */
  26 #ifdef HAVE_CONFIG_H
  27 # include "config.h"
  28 #endif
  29
  30 #include "typerep.h"
  31 #include "irgraph_t.h"
  32 #include "irprog_t.h"
  33 #include "irprintf.h"
  34 #include "pset.h"
  35 #include "set.h"
  36 #include "irgwalk.h"
  37 #include "irflag.h"
  38
  39
  40 /* ----------------------------------------------------------------------- */
  41 /* Resolve implicit inheritance.                                           */
  42 /* ----------------------------------------------------------------------- */
  43
  44 ident *default_mangle_inherited_name(ir_entity *super, ir_type *clss) {
  45         return mangle_u(new_id_from_str("inh"), mangle_u(get_type_ident(clss), get_entity_ident(super)));
  46 }
  47
  48 /** Replicates all entities in all super classes that are not overwritten
  49     by an entity of this class. */
  50 static void copy_entities_from_superclass(ir_type *clss, void *env)
  51 {
  52         int i, j, k, l;
  53         int overwritten;
  54         ir_type *super, *inhenttype;
  55         ir_entity *inhent, *thisent;
  56         mangle_inherited_name_func *mfunc = *(mangle_inherited_name_func **)env;
  57
  58         for(i = 0; i < get_class_n_supertypes(clss); i++) {
  59                 super = get_class_supertype(clss, i);
  60                 assert(is_Class_type(super) && "not a class");
  61                 for(j = 0; j < get_class_n_members(super); j++) {
  62                         inhent = get_class_member(super, j);
  63                         inhenttype = get_entity_type(inhent);
  64                         /* check whether inhent is already overwritten */
  65                         overwritten = 0;
  66                         for (k = 0; (k < get_class_n_members(clss)) && (overwritten == 0); k++) {
  67                                 thisent = get_class_member(clss, k);
  68                                 for(l = 0; l < get_entity_n_overwrites(thisent); l++) {
  69                                         if(inhent == get_entity_overwrites(thisent, l)) {
  70                                                 /* overwritten - do not copy */
  71                                                 overwritten = 1;
  72                                                 break;
  73                                         }
  74                                 }
  75                         }
  76                         /* Inherit entity */
  77                         if (!overwritten) {
  78                                 thisent = copy_entity_own(inhent, clss);
  79                                 add_entity_overwrites(thisent, inhent);
  80                                 if (get_entity_peculiarity(inhent) == peculiarity_existent)
  81                                         set_entity_peculiarity(thisent, peculiarity_inherited);
  82                                 set_entity_ld_ident(thisent, mfunc(inhent, clss));
  83                                 if (get_entity_variability(inhent) == variability_constant) {
  84                                         assert(is_atomic_entity(inhent) &&  /* @@@ */
  85                                                 "Inheritance of constant, compound entities not implemented");
  86                                         set_entity_variability(thisent, variability_constant);
  87                                         set_atomic_ent_value(thisent, get_atomic_ent_value(inhent));
  88                                 }
  89                         }
  90                 }
  91         }
  92 }
  93
  94 /* Resolve implicit inheritance.
  95  *
  96  *  Resolves the implicit inheritance supplied by firm.
  97  */
  98 void resolve_inheritance(mangle_inherited_name_func *mfunc) {
  99         if (!mfunc)
 100                 mfunc = default_mangle_inherited_name;
 101         class_walk_super2sub(copy_entities_from_superclass, NULL, (void *)&mfunc);
 102 }
 103
 104
 105 /* ----------------------------------------------------------------------- */
 106 /* The transitive closure of the subclass/superclass and                   */
 107 /* overwrites/overwrittenby relation.                                      */
 108 /*                                                                         */
 109 /* A walk over the ir (O(#types+#entities)) computes the transitive        */
 110 /* closure.  Adding a new type/entity or changing the basic relations in   */
 111 /* some other way invalidates the transitive closure, i.e., it is not      */
 112 /* updated by the basic functions.                                         */
 113 /*                                                                         */
 114 /* All functions are named as their counterparts for the basic relations,  */
 115 /* adding the infix 'trans_'.                                              */
 116 /* ----------------------------------------------------------------------- */
 117
 118 void                        set_irp_inh_transitive_closure_state(inh_transitive_closure_state s) {
 119         irp->inh_trans_closure_state = s;
 120 }
 121 void                        invalidate_irp_inh_transitive_closure_state(void) {
 122         if (irp->inh_trans_closure_state == inh_transitive_closure_valid)
 123                 irp->inh_trans_closure_state = inh_transitive_closure_invalid;
 124 }
 125 inh_transitive_closure_state get_irp_inh_transitive_closure_state(void) {
 126         return irp->inh_trans_closure_state;
 127 }
 128
 129 static void assert_valid_state(void) {
 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         const tr_inh_trans_tp *ef1 = e1;
 160         const tr_inh_trans_tp *ef2 = e2;
 161         (void) size;
 162
 163         return ef1->kind != ef2->kind;
 164 }
 165
 166 /**
 167  * calculate the hash value of an tr_inh_trans_tp
 168  */
 169 static INLINE unsigned int tr_inh_trans_hash(const tr_inh_trans_tp *v) {
 170         return HASH_PTR(v->kind);
 171 }
 172
 173 /* This always completes successfully. */
 174 static tr_inh_trans_tp *get_firm_kind_entry(const firm_kind *k) {
 175         tr_inh_trans_tp a, *found;
 176         a.kind = k;
 177
 178         if (!tr_inh_trans_set) tr_inh_trans_set = new_set(tr_inh_trans_cmp, 128);
 179
 180         found = set_find(tr_inh_trans_set, &a, sizeof(a), tr_inh_trans_hash(&a));
 181         if (!found) {
 182                 a.directions[d_up]   = pset_new_ptr(16);
 183                 a.directions[d_down] = pset_new_ptr(16);
 184                 found = set_insert(tr_inh_trans_set, &a, sizeof(a), tr_inh_trans_hash(&a));
 185         }
 186         return found;
 187 }
 188
 189 static pset *get_entity_map(const ir_entity *ent, dir d) {
 190         tr_inh_trans_tp *found;
 191
 192         assert(is_entity(ent));
 193         found = get_firm_kind_entry((const firm_kind *)ent);
 194         return found->directions[d];
 195 }
 196
 197 static pset *get_type_map(const ir_type *tp, dir d) {
 198         tr_inh_trans_tp *found;
 199
 200         assert(is_type(tp));
 201         found = get_firm_kind_entry((const firm_kind *)tp);
 202         return found->directions[d];
 203 }
 204
 205
 206 /**
 207  * Walk over all types reachable from tp in the sub/supertype
 208  * relation and compute the closure for the two downwards directed
 209  * relations.
 210  *
 211  * The walk in the dag formed by the relation is tricky:  We must visit
 212  * all subtypes before visiting the supertypes.  So we first walk down.
 213  * Then we can compute the closure for this type.  Then we walk up.
 214  * As we call ourselves recursive, and walk in both directions, there
 215  * can be cycles.  So we have to make sure, that if we visit a node
 216  * a second time (in a walk up) we do nothing.  For this we increment
 217  * the master visited flag twice.
 218  * If the type is marked with master_flag_visited-1 it is on the stack.
 219  * If it is marked with master_flag_visited it is fully processed.
 220  *
 221  * Well, we still miss some candidates ... */
 222 static void compute_down_closure(ir_type *tp) {
 223         pset *myset, *subset;
 224         int i, n_subtypes, n_members, n_supertypes;
 225         unsigned long master_visited = get_master_type_visited();
 226
 227         assert(is_Class_type(tp));
 228
 229         set_type_visited(tp, master_visited-1);
 230
 231         /* Recursive descend. */
 232         n_subtypes = get_class_n_subtypes(tp);
 233         for (i = 0; i < n_subtypes; ++i) {
 234                 ir_type *stp = get_class_subtype(tp, i);
 235                 if (get_type_visited(stp) < master_visited-1) {
 236                         compute_down_closure(stp);
 237                 }
 238         }
 239
 240         /* types */
 241         myset = get_type_map(tp, d_down);
 242         for (i = 0; i < n_subtypes; ++i) {
 243                 ir_type *stp = get_class_subtype(tp, i);
 244                 subset = get_type_map(stp, d_down);
 245                 pset_insert_ptr(myset, stp);
 246                 pset_insert_pset_ptr(myset, subset);
 247         }
 248
 249         /* entities */
 250         n_members = get_class_n_members(tp);
 251         for (i = 0; i < n_members; ++i) {
 252                 ir_entity *mem = get_class_member(tp, i);
 253                 int j, n_overwrittenby = get_entity_n_overwrittenby(mem);
 254
 255                 myset = get_entity_map(mem, d_down);
 256                 for (j = 0; j < n_overwrittenby; ++j) {
 257                         ir_entity *ov = get_entity_overwrittenby(mem, j);
 258                         subset = get_entity_map(ov, d_down);
 259                         pset_insert_ptr(myset, ov);
 260                         pset_insert_pset_ptr(myset, subset);
 261                 }
 262         }
 263
 264         mark_type_visited(tp);
 265
 266         /* Walk up. */
 267         n_supertypes = get_class_n_supertypes(tp);
 268         for (i = 0; i < n_supertypes; ++i) {
 269                 ir_type *stp = get_class_supertype(tp, i);
 270                 if (get_type_visited(stp) < master_visited-1) {
 271                         compute_down_closure(stp);
 272                 }
 273         }
 274 }
 275
 276 static void compute_up_closure(ir_type *tp) {
 277         pset *myset, *subset;
 278         int i, n_subtypes, n_members, n_supertypes;
 279         unsigned long master_visited = get_master_type_visited();
 280
 281         assert(is_Class_type(tp));
 282
 283         set_type_visited(tp, master_visited-1);
 284
 285         /* Recursive descend. */
 286         n_supertypes = get_class_n_supertypes(tp);
 287         for (i = 0; i < n_supertypes; ++i) {
 288                 ir_type *stp = get_class_supertype(tp, i);
 289                 if (get_type_visited(stp) < get_master_type_visited()-1) {
 290                         compute_up_closure(stp);
 291                 }
 292         }
 293
 294         /* types */
 295         myset = get_type_map(tp, d_up);
 296         for (i = 0; i < n_supertypes; ++i) {
 297                 ir_type *stp = get_class_supertype(tp, i);
 298                 subset = get_type_map(stp, d_up);
 299                 pset_insert_ptr(myset, stp);
 300                 pset_insert_pset_ptr(myset, subset);
 301         }
 302
 303         /* entities */
 304         n_members = get_class_n_members(tp);
 305         for (i = 0; i < n_members; ++i) {
 306                 ir_entity *mem = get_class_member(tp, i);
 307                 int j, n_overwrites = get_entity_n_overwrites(mem);
 308
 309                 myset = get_entity_map(mem, d_up);
 310                 for (j = 0; j < n_overwrites; ++j) {
 311                         ir_entity *ov = get_entity_overwrites(mem, j);
 312                         subset = get_entity_map(ov, d_up);
 313                         pset_insert_pset_ptr(myset, subset);
 314                         pset_insert_ptr(myset, ov);
 315                 }
 316         }
 317
 318         mark_type_visited(tp);
 319
 320         /* Walk down. */
 321         n_subtypes = get_class_n_subtypes(tp);
 322         for (i = 0; i < n_subtypes; ++i) {
 323                 ir_type *stp = get_class_subtype(tp, i);
 324                 if (get_type_visited(stp) < master_visited-1) {
 325                         compute_up_closure(stp);
 326                 }
 327         }
 328 }
 329
 330 /** Compute the transitive closure of the subclass/superclass and
 331  *  overwrites/overwrittenby relation.
 332  *
 333  *  This function walks over the ir (O(#types+#entities)) to compute the
 334  *  transitive closure.    */
 335 void compute_inh_transitive_closure(void) {
 336         int i, n_types = get_irp_n_types();
 337         free_inh_transitive_closure();
 338
 339         /* The 'down' relation */
 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                         int 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                         int 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 }
 389
 390 /** Free memory occupied by the transitive closure information. */
 391 void free_inh_transitive_closure(void) {
 392         if (tr_inh_trans_set) {
 393                 tr_inh_trans_tp *elt;
 394                 for (elt = set_first(tr_inh_trans_set); elt; elt = set_next(tr_inh_trans_set)) {
 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         assert_valid_state();
 408         return pset_first(get_type_map(tp, d_down));
 409 }
 410
 411 ir_type *get_class_trans_subtype_next(const ir_type *tp) {
 412         assert_valid_state();
 413         return pset_next(get_type_map(tp, d_down));
 414 }
 415
 416 int is_class_trans_subtype(const ir_type *tp, const ir_type *subtp) {
 417         assert_valid_state();
 418         return (pset_find_ptr(get_type_map(tp, d_down), subtp) != NULL);
 419 }
 420
 421 /* - supertype ----------------------------------------------------------- */
 422
 423 ir_type *get_class_trans_supertype_first(const ir_type *tp) {
 424         assert_valid_state();
 425         return pset_first(get_type_map(tp, d_up));
 426 }
 427
 428 ir_type *get_class_trans_supertype_next(const ir_type *tp) {
 429         assert_valid_state();
 430         return pset_next(get_type_map(tp, d_up));
 431 }
 432
 433 /* - overwrittenby ------------------------------------------------------- */
 434
 435 ir_entity *get_entity_trans_overwrittenby_first(const ir_entity *ent) {
 436         assert_valid_state();
 437         return pset_first(get_entity_map(ent, d_down));
 438 }
 439
 440 ir_entity *get_entity_trans_overwrittenby_next(const ir_entity *ent) {
 441         assert_valid_state();
 442         return pset_next(get_entity_map(ent, d_down));
 443 }
 444
 445 /* - overwrites ---------------------------------------------------------- */
 446
 447
 448 /** Iterate over all transitive overwritten entities. */
 449 ir_entity *get_entity_trans_overwrites_first(const ir_entity *ent) {
 450         assert_valid_state();
 451         return pset_first(get_entity_map(ent, d_up));
 452 }
 453
 454 ir_entity *get_entity_trans_overwrites_next(const ir_entity *ent) {
 455         assert_valid_state();
 456         return pset_next(get_entity_map(ent, d_up));
 457 }
 458
 459
 460 /* ----------------------------------------------------------------------- */
 461 /* Classify pairs of types/entities in the inheritance relations.          */
 462 /* ----------------------------------------------------------------------- */
 463
 464 /** Returns true if low is subclass of high. */
 465 static int check_is_SubClass_of(ir_type *low, ir_type *high) {
 466         int i, n_subtypes;
 467
 468         /* depth first search from high downwards. */
 469         n_subtypes = get_class_n_subtypes(high);
 470         for (i = 0; i < n_subtypes; i++) {
 471                 ir_type *stp = get_class_subtype(high, i);
 472                 if (low == stp) return 1;
 473                 if (is_SubClass_of(low, stp))
 474                         return 1;
 475         }
 476         return 0;
 477 }
 478
 479 /* Returns true if low is subclass of high. */
 480 int is_SubClass_of(ir_type *low, ir_type *high) {
 481         assert(is_Class_type(low) && is_Class_type(high));
 482
 483         if (low == high) return 1;
 484
 485         if (get_irp_inh_transitive_closure_state() == inh_transitive_closure_valid) {
 486                 pset *m = get_type_map(high, d_down);
 487                 return pset_find_ptr(m, low) ? 1 : 0;
 488         }
 489         return check_is_SubClass_of(low, high);
 490 }
 491
 492
 493 /* Subclass check for pointers to classes.
 494  *
 495  *  Dereferences at both types the same amount of pointer types (as
 496  *  many as possible).  If the remaining types are both class types
 497  *  and subclasses, returns true, else false.  Can also be called with
 498  *  two class types.  */
 499 int is_SubClass_ptr_of(ir_type *low, ir_type *high) {
 500         while (is_Pointer_type(low) && is_Pointer_type(high)) {
 501                 low  = get_pointer_points_to_type(low);
 502                 high = get_pointer_points_to_type(high);
 503         }
 504
 505         if (is_Class_type(low) && is_Class_type(high))
 506                 return is_SubClass_of(low, high);
 507         return 0;
 508 }
 509
 510 int is_overwritten_by(ir_entity *high, ir_entity *low) {
 511         int i, n_overwrittenby;
 512         assert(is_entity(low) && is_entity(high));
 513
 514         if (get_irp_inh_transitive_closure_state() == inh_transitive_closure_valid) {
 515                 pset *m = get_entity_map(high, d_down);
 516                 return pset_find_ptr(m, low) ? 1 : 0;
 517         }
 518
 519         /* depth first search from high downwards. */
 520         n_overwrittenby = get_entity_n_overwrittenby(high);
 521         for (i = 0; i < n_overwrittenby; i++) {
 522                 ir_entity *ov = get_entity_overwrittenby(high, i);
 523                 if (low == ov) return 1;
 524                 if (is_overwritten_by(low, ov))
 525                         return 1;
 526         }
 527         return 0;
 528 }
 529
 530 /** Resolve polymorphy in the inheritance relation.
 531  *
 532  * Returns the dynamically referenced entity if the static entity and the
 533  * dynamic type are given.
 534  * Search downwards in overwritten tree.
 535  *
 536  * Need two routines because I want to assert the result.
 537  */
 538 static ir_entity *do_resolve_ent_polymorphy(ir_type *dynamic_class, ir_entity *static_ent) {
 539         int i, n_overwrittenby;
 540
 541         if (get_entity_owner(static_ent) == dynamic_class) return static_ent;
 542
 543         n_overwrittenby = get_entity_n_overwrittenby(static_ent);
 544         for (i = 0; i < n_overwrittenby; ++i) {
 545                 ir_entity *ent = get_entity_overwrittenby(static_ent, i);
 546                 ent = do_resolve_ent_polymorphy(dynamic_class, ent);
 547                 if (ent) return ent;
 548         }
 549         return NULL;
 550 }
 551
 552 /* Resolve polymorphy in the inheritance relation.
 553  *
 554  * Returns the dynamically referenced entity if the static entity and the
 555  * dynamic type are given.
 556  * Search downwards in overwritten tree. */
 557 ir_entity *resolve_ent_polymorphy(ir_type *dynamic_class, ir_entity *static_ent) {
 558         ir_entity *res;
 559         assert(static_ent && is_entity(static_ent));
 560
 561         res = do_resolve_ent_polymorphy(dynamic_class, static_ent);
 562         assert(res);
 563
 564         return res;
 565 }
 566
 567
 568
 569 /* ----------------------------------------------------------------------- */
 570 /* Class cast state handling.                                              */
 571 /* ----------------------------------------------------------------------- */
 572
 573 /* - State handling. ----------------------------------------- */
 574
 575 void set_irg_class_cast_state(ir_graph *irg, ir_class_cast_state s) {
 576         if (get_irp_class_cast_state() > s) set_irp_class_cast_state(s);
 577         irg->class_cast_state = s;
 578 }
 579
 580 ir_class_cast_state get_irg_class_cast_state(ir_graph *irg) {
 581         return irg->class_cast_state;
 582 }
 583
 584 void set_irp_class_cast_state(ir_class_cast_state s) {
 585 #ifndef NDEBUG
 586         int i;
 587         for (i = get_irp_n_irgs() - 1; i >= 0; --i)
 588                 assert(get_irg_class_cast_state(get_irp_irg(i)) >= s);
 589 #endif
 590         irp->class_cast_state = s;
 591 }
 592
 593 ir_class_cast_state get_irp_class_cast_state(void) {
 594         return irp->class_cast_state;
 595 }
 596
 597 char *get_class_cast_state_string(ir_class_cast_state s) {
 598 #define X(a)    case a: return #a
 599         switch(s) {
 600         X(ir_class_casts_any);
 601         X(ir_class_casts_transitive);
 602         X(ir_class_casts_normalized);
 603         X(ir_class_casts_state_max);
 604         default: return "invalid class cast state";
 605         }
 606 #undef X
 607 }
 608
 609 /* - State verification. ------------------------------------- */
 610
 611 typedef struct ccs_env {
 612         ir_class_cast_state expected_state;
 613         ir_class_cast_state worst_situation;
 614 } ccs_env;
 615
 616 void verify_irn_class_cast_state(ir_node *n, void *env) {
 617         ccs_env             *ccs = (ccs_env *)env;
 618         ir_class_cast_state this_state = ir_class_casts_any;
 619         ir_type             *fromtype, *totype;
 620         int                 ref_depth = 0;
 621
 622         if (get_irn_op(n) != op_Cast) return;
 623
 624         fromtype = get_irn_typeinfo_type(get_Cast_op(n));
 625         totype   = get_Cast_type(n);
 626
 627         while (is_Pointer_type(totype) && is_Pointer_type(fromtype)) {
 628                 totype   = get_pointer_points_to_type(totype);
 629                 fromtype = get_pointer_points_to_type(fromtype);
 630                 ref_depth++;
 631         }
 632
 633         if (!is_Class_type(totype)) return;
 634
 635         if (is_SubClass_of(totype, fromtype) ||
 636                 is_SubClass_of(fromtype, totype)   ) {
 637                 this_state = ir_class_casts_transitive;
 638                 if ((get_class_supertype_index(totype, fromtype) != -1) ||
 639                     (get_class_supertype_index(fromtype, totype) != -1) ||
 640                     fromtype == totype) {
 641                         /*   Das ist doch alt?  Aus dem cvs aufgetaucht ...
 642                         if ((get_class_supertype_index(totype, fromtype) == -1) &&
 643                             (get_class_supertype_index(fromtype, totype) == -1) ) {  */
 644                         this_state = ir_class_casts_normalized;
 645                 }
 646         }
 647
 648         if (!(this_state >= ccs->expected_state)) {
 649                 ir_printf("  Node is %+F\n", n);
 650                 ir_printf("    totype   %+F\n", totype);
 651                 ir_printf("    fromtype %+F\n", fromtype);
 652                 ir_printf("    this_state: %s, exp. state: %s\n",
 653                         get_class_cast_state_string(this_state),
 654                         get_class_cast_state_string(ccs->expected_state));
 655                 assert(this_state >= ccs->expected_state &&
 656                         "invalid state class cast state setting in graph");
 657         }
 658
 659         if (this_state < ccs->worst_situation)
 660                 ccs->worst_situation = this_state;
 661 }
 662
 663 /** Verify that the graph meets requirements of state set. */
 664 void verify_irg_class_cast_state(ir_graph *irg) {
 665         ccs_env env;
 666
 667         env.expected_state  = get_irg_class_cast_state(irg);
 668         env.worst_situation = ir_class_casts_normalized;
 669
 670         irg_walk_graph(irg, NULL, verify_irn_class_cast_state, &env);
 671
 672         if ((env.worst_situation > env.expected_state) && get_firm_verbosity()) {
 673                 ir_printf("Note:  class cast state is set lower than reqired in graph \n\t%+F\n", irg);
 674                 printf("       state is %s, reqired is %s\n",
 675                         get_class_cast_state_string(env.expected_state),
 676                         get_class_cast_state_string(env.worst_situation));
 677         }
 678 }