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         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 static int tr_inh_trans_cmp(const void *e1, const void *e2, size_t size) {
 156         tr_inh_trans_tp *ef1 = (tr_inh_trans_tp *)e1;
 157         tr_inh_trans_tp *ef2 = (tr_inh_trans_tp *)e2;
 158         return (ef1->kind != ef2->kind);
 159 }
 160
 161 static INLINE unsigned int tr_inh_trans_hash(void *e) {
 162         tr_inh_trans_tp *v = e;
 163         return HASH_PTR(v->kind);
 164 }
 165
 166 /* This always completes successfully. */
 167 static tr_inh_trans_tp* get_firm_kind_entry(firm_kind *k) {
 168         tr_inh_trans_tp a, *found;
 169         a.kind = k;
 170
 171         if (!tr_inh_trans_set) tr_inh_trans_set = new_set(tr_inh_trans_cmp, 128);
 172
 173         found = set_find(tr_inh_trans_set, &a, sizeof(a), tr_inh_trans_hash(&a));
 174         if (!found) {
 175                 a.directions[d_up]   = pset_new_ptr(16);
 176                 a.directions[d_down] = pset_new_ptr(16);
 177                 found = set_insert(tr_inh_trans_set, &a, sizeof(a), tr_inh_trans_hash(&a));
 178         }
 179         return found;
 180 }
 181
 182 static pset *get_entity_map(ir_entity *ent, dir d) {
 183         tr_inh_trans_tp *found;
 184
 185         assert(is_entity(ent));
 186         found = get_firm_kind_entry((firm_kind *)ent);
 187         return found->directions[d];
 188 }
 189 /*
 190 static void  add_entity_map(ir_entity *ent, dir d, ir_entity *new) {
 191         tr_inh_trans_tp *found;
 192
 193         assert(is_entity(ent) && is_entity(new));
 194         tr_inh_trans_tp *found = get_firm_kind_entry((firm_kind *)ent);
 195         pset_insert_ptr(found->directions[d], new);
 196 }
 197 */
 198 static pset *get_type_map(ir_type *tp, dir d) {
 199         tr_inh_trans_tp *found;
 200
 201         assert(is_type(tp));
 202         found = get_firm_kind_entry((firm_kind *)tp);
 203         return found->directions[d];
 204 }
 205 /*
 206 static void  add_type_map(ir_type *tp, dir d, type *new) {
 207         tr_inh_trans_tp *found;
 208
 209         assert(is_type(tp) && is_type(new));
 210         found = get_firm_kind_entry((firm_kind *)tp);
 211         pset_insert_ptr(found->directions[d], new);
 212 }
 213 */
 214
 215
 216 /**
 217  * Walk over all types reachable from tp in the sub/supertype
 218  * relation and compute the closure for the two downwards directed
 219  * relations.
 220  *
 221  * The walk in the dag formed by the relation is tricky:  We must visit
 222  * all subtypes before visiting the supertypes.  So we first walk down.
 223  * Then we can compute the closure for this type.  Then we walk up.
 224  * As we call ourselves recursive, and walk in both directions, there
 225  * can be cycles.  So we have to make sure, that if we visit a node
 226  * a second time (in a walk up) we do nothing.  For this we increment
 227  * the master visited flag twice.
 228  * If the type is marked with master_flag_visited-1 it is on the stack.
 229  * If it is marked with master_flag_visited it is fully processed.
 230  *
 231  * Well, we still miss some candidates ... */
 232 static void compute_down_closure(ir_type *tp) {
 233         pset *myset, *subset;
 234         int i, n_subtypes, n_members, n_supertypes;
 235         unsigned long master_visited = get_master_type_visited();
 236
 237         assert(is_Class_type(tp));
 238
 239         set_type_visited(tp, master_visited-1);
 240
 241         /* Recursive descend. */
 242         n_subtypes = get_class_n_subtypes(tp);
 243         for (i = 0; i < n_subtypes; ++i) {
 244                 ir_type *stp = get_class_subtype(tp, i);
 245                 if (get_type_visited(stp) < master_visited-1) {
 246                         compute_down_closure(stp);
 247                 }
 248         }
 249
 250         /* types */
 251         myset = get_type_map(tp, d_down);
 252         for (i = 0; i < n_subtypes; ++i) {
 253                 ir_type *stp = get_class_subtype(tp, i);
 254                 subset = get_type_map(stp, d_down);
 255                 pset_insert_ptr(myset, stp);
 256                 pset_insert_pset_ptr(myset, subset);
 257         }
 258
 259         /* entities */
 260         n_members = get_class_n_members(tp);
 261         for (i = 0; i < n_members; ++i) {
 262                 ir_entity *mem = get_class_member(tp, i);
 263                 int j, n_overwrittenby = get_entity_n_overwrittenby(mem);
 264
 265                 myset = get_entity_map(mem, d_down);
 266                 for (j = 0; j < n_overwrittenby; ++j) {
 267                         ir_entity *ov = get_entity_overwrittenby(mem, j);
 268                         subset = get_entity_map(ov, d_down);
 269                         pset_insert_ptr(myset, ov);
 270                         pset_insert_pset_ptr(myset, subset);
 271                 }
 272         }
 273
 274         mark_type_visited(tp);
 275
 276         /* Walk up. */
 277         n_supertypes = get_class_n_supertypes(tp);
 278         for (i = 0; i < n_supertypes; ++i) {
 279                 ir_type *stp = get_class_supertype(tp, i);
 280                 if (get_type_visited(stp) < master_visited-1) {
 281                         compute_down_closure(stp);
 282                 }
 283         }
 284 }
 285
 286 static void compute_up_closure(ir_type *tp) {
 287         pset *myset, *subset;
 288         int i, n_subtypes, n_members, n_supertypes;
 289         unsigned long master_visited = get_master_type_visited();
 290
 291         assert(is_Class_type(tp));
 292
 293         set_type_visited(tp, master_visited-1);
 294
 295         /* Recursive descend. */
 296         n_supertypes = get_class_n_supertypes(tp);
 297         for (i = 0; i < n_supertypes; ++i) {
 298                 ir_type *stp = get_class_supertype(tp, i);
 299                 if (get_type_visited(stp) < get_master_type_visited()-1) {
 300                         compute_up_closure(stp);
 301                 }
 302         }
 303
 304         /* types */
 305         myset = get_type_map(tp, d_up);
 306         for (i = 0; i < n_supertypes; ++i) {
 307                 ir_type *stp = get_class_supertype(tp, i);
 308                 subset = get_type_map(stp, d_up);
 309                 pset_insert_ptr(myset, stp);
 310                 pset_insert_pset_ptr(myset, subset);
 311         }
 312
 313         /* entities */
 314         n_members = get_class_n_members(tp);
 315         for (i = 0; i < n_members; ++i) {
 316                 ir_entity *mem = get_class_member(tp, i);
 317                 int j, n_overwrites = get_entity_n_overwrites(mem);
 318
 319                 myset = get_entity_map(mem, d_up);
 320                 for (j = 0; j < n_overwrites; ++j) {
 321                         ir_entity *ov = get_entity_overwrites(mem, j);
 322                         subset = get_entity_map(ov, d_up);
 323                         pset_insert_pset_ptr(myset, subset);
 324                         pset_insert_ptr(myset, ov);
 325                 }
 326         }
 327
 328         mark_type_visited(tp);
 329
 330         /* Walk down. */
 331         n_subtypes = get_class_n_subtypes(tp);
 332         for (i = 0; i < n_subtypes; ++i) {
 333                 ir_type *stp = get_class_subtype(tp, i);
 334                 if (get_type_visited(stp) < master_visited-1) {
 335                         compute_up_closure(stp);
 336                 }
 337         }
 338 }
 339
 340 /** Compute the transitive closure of the subclass/superclass and
 341  *  overwrites/overwrittenby relation.
 342  *
 343  *  This function walks over the ir (O(#types+#entities)) to compute the
 344  *  transitive closure.    */
 345 void compute_inh_transitive_closure(void) {
 346         int i, n_types = get_irp_n_types();
 347         free_inh_transitive_closure();
 348
 349         /* The 'down' relation */
 350         inc_master_type_visited();  /* Inc twice: one if on stack, second if values computed. */
 351         inc_master_type_visited();
 352         for (i = 0; i < n_types; ++i) {
 353                 ir_type *tp = get_irp_type(i);
 354                 if (is_Class_type(tp) && type_not_visited(tp)) { /* For others there is nothing to accumulate. */
 355                         int j, n_subtypes = get_class_n_subtypes(tp);
 356                         int has_unmarked_subtype = 0;
 357
 358                         assert(get_type_visited(tp) < get_master_type_visited()-1);
 359                         for (j = 0; j < n_subtypes; ++j) {
 360                                 ir_type *stp = get_class_subtype(tp, j);
 361                                 if (type_not_visited(stp)) {
 362                                         has_unmarked_subtype = 1;
 363                                         break;
 364                                 }
 365                         }
 366
 367                         /* This is a good starting point. */
 368                         if (!has_unmarked_subtype)
 369                                 compute_down_closure(tp);
 370                 }
 371         }
 372
 373         /* The 'up' relation */
 374         inc_master_type_visited();
 375         inc_master_type_visited();
 376         for (i = 0; i < n_types; ++i) {
 377                 ir_type *tp = get_irp_type(i);
 378                 if (is_Class_type(tp) && type_not_visited(tp)) { /* For others there is nothing to accumulate. */
 379                         int j, n_supertypes = get_class_n_supertypes(tp);
 380                         int has_unmarked_supertype = 0;
 381
 382                         assert(get_type_visited(tp) < get_master_type_visited()-1);
 383                         for (j = 0; j < n_supertypes; ++j) {
 384                                 ir_type *stp = get_class_supertype(tp, j);
 385                                 if (type_not_visited(stp)) {
 386                                         has_unmarked_supertype = 1;
 387                                         break;
 388                                 }
 389                         }
 390
 391                         /* This is a good starting point. */
 392                         if (!has_unmarked_supertype)
 393                                 compute_up_closure(tp);
 394                 }
 395         }
 396
 397         irp->inh_trans_closure_state = inh_transitive_closure_valid;
 398 }
 399
 400 /** Free memory occupied by the transitive closure information. */
 401 void free_inh_transitive_closure(void) {
 402         if (tr_inh_trans_set) {
 403                 tr_inh_trans_tp *elt;
 404                 for (elt = set_first(tr_inh_trans_set); elt; elt = set_next(tr_inh_trans_set)) {
 405                         del_pset(elt->directions[d_up]);
 406                         del_pset(elt->directions[d_down]);
 407                 }
 408                 del_set(tr_inh_trans_set);
 409                 tr_inh_trans_set = NULL;
 410         }
 411         irp->inh_trans_closure_state = inh_transitive_closure_none;
 412 }
 413
 414 /* - subtype ------------------------------------------------------------- */
 415
 416 ir_type *get_class_trans_subtype_first(ir_type *tp) {
 417         assert_valid_state();
 418         return pset_first(get_type_map(tp, d_down));
 419 }
 420
 421 ir_type *get_class_trans_subtype_next (ir_type *tp) {
 422         assert_valid_state();
 423         return pset_next(get_type_map(tp, d_down));
 424 }
 425
 426 int is_class_trans_subtype (ir_type *tp, ir_type *subtp) {
 427         assert_valid_state();
 428         return (pset_find_ptr(get_type_map(tp, d_down), subtp) != NULL);
 429 }
 430
 431 /* - supertype ----------------------------------------------------------- */
 432
 433 ir_type *get_class_trans_supertype_first(ir_type *tp) {
 434         assert_valid_state();
 435         return pset_first(get_type_map(tp, d_up));
 436 }
 437
 438 ir_type *get_class_trans_supertype_next (ir_type *tp) {
 439         assert_valid_state();
 440         return pset_next(get_type_map(tp, d_up));
 441 }
 442
 443 /* - overwrittenby ------------------------------------------------------- */
 444
 445 ir_entity *get_entity_trans_overwrittenby_first(ir_entity *ent) {
 446         assert_valid_state();
 447         return pset_first(get_entity_map(ent, d_down));
 448 }
 449
 450 ir_entity *get_entity_trans_overwrittenby_next (ir_entity *ent) {
 451         assert_valid_state();
 452         return pset_next(get_entity_map(ent, d_down));
 453 }
 454
 455 /* - overwrites ---------------------------------------------------------- */
 456
 457
 458 /** Iterate over all transitive overwritten entities. */
 459 ir_entity *get_entity_trans_overwrites_first(ir_entity *ent) {
 460         assert_valid_state();
 461         return pset_first(get_entity_map(ent, d_up));
 462 }
 463
 464 ir_entity *get_entity_trans_overwrites_next (ir_entity *ent) {
 465         assert_valid_state();
 466         return pset_next(get_entity_map(ent, d_up));
 467 }
 468
 469
 470
 471
 472
 473 /* ----------------------------------------------------------------------- */
 474 /* Classify pairs of types/entities in the inheritance relations.          */
 475 /* ----------------------------------------------------------------------- */
 476
 477 /** Returns true if low is subclass of high. */
 478 static int check_is_SubClass_of(ir_type *low, ir_type *high) {
 479         int i, n_subtypes;
 480
 481         /* depth first search from high downwards. */
 482         n_subtypes = get_class_n_subtypes(high);
 483         for (i = 0; i < n_subtypes; i++) {
 484                 ir_type *stp = get_class_subtype(high, i);
 485                 if (low == stp) return 1;
 486                 if (is_SubClass_of(low, stp))
 487                         return 1;
 488         }
 489         return 0;
 490 }
 491
 492 /* Returns true if low is subclass of high. */
 493 int is_SubClass_of(ir_type *low, ir_type *high) {
 494         assert(is_Class_type(low) && is_Class_type(high));
 495
 496         if (low == high) return 1;
 497
 498         if (get_irp_inh_transitive_closure_state() == inh_transitive_closure_valid) {
 499                 pset *m = get_type_map(high, d_down);
 500                 return pset_find_ptr(m, low) ? 1 : 0;
 501         }
 502         return check_is_SubClass_of(low, high);
 503 }
 504
 505
 506 /* Subclass check for pointers to classes.
 507  *
 508  *  Dereferences at both types the same amount of pointer types (as
 509  *  many as possible).  If the remaining types are both class types
 510  *  and subclasses, returns true, else false.  Can also be called with
 511  *  two class types.  */
 512 int is_SubClass_ptr_of(ir_type *low, ir_type *high) {
 513         while (is_Pointer_type(low) && is_Pointer_type(high)) {
 514                 low  = get_pointer_points_to_type(low);
 515                 high = get_pointer_points_to_type(high);
 516         }
 517
 518         if (is_Class_type(low) && is_Class_type(high))
 519                 return is_SubClass_of(low, high);
 520         return 0;
 521 }
 522
 523 int is_overwritten_by(ir_entity *high, ir_entity *low) {
 524         int i, n_overwrittenby;
 525         assert(is_entity(low) && is_entity(high));
 526
 527         if (get_irp_inh_transitive_closure_state() == inh_transitive_closure_valid) {
 528                 pset *m = get_entity_map(high, d_down);
 529                 return pset_find_ptr(m, low) ? 1 : 0;
 530         }
 531
 532         /* depth first search from high downwards. */
 533         n_overwrittenby = get_entity_n_overwrittenby(high);
 534         for (i = 0; i < n_overwrittenby; i++) {
 535                 ir_entity *ov = get_entity_overwrittenby(high, i);
 536                 if (low == ov) return 1;
 537                 if (is_overwritten_by(low, ov))
 538                         return 1;
 539         }
 540         return 0;
 541 }
 542
 543 /** Resolve polymorphy in the inheritance relation.
 544  *
 545  * Returns the dynamically referenced entity if the static entity and the
 546  * dynamic type are given.
 547  * Search downwards in overwritten tree.
 548  *
 549  * Need two routines because I want to assert the result.
 550  */
 551 static ir_entity *do_resolve_ent_polymorphy(ir_type *dynamic_class, ir_entity *static_ent) {
 552         int i, n_overwrittenby;
 553
 554         if (get_entity_owner(static_ent) == dynamic_class) return static_ent;
 555
 556         n_overwrittenby = get_entity_n_overwrittenby(static_ent);
 557         for (i = 0; i < n_overwrittenby; ++i) {
 558                 ir_entity *ent = get_entity_overwrittenby(static_ent, i);
 559                 ent = do_resolve_ent_polymorphy(dynamic_class, ent);
 560                 if (ent) return ent;
 561         }
 562         return NULL;
 563 }
 564
 565 /* Resolve polymorphy in the inheritance relation.
 566  *
 567  * Returns the dynamically referenced entity if the static entity and the
 568  * dynamic type are given.
 569  * Search downwards in overwritten tree. */
 570 ir_entity *resolve_ent_polymorphy(ir_type *dynamic_class, ir_entity *static_ent) {
 571         ir_entity *res;
 572         assert(static_ent && is_entity(static_ent));
 573
 574         res = do_resolve_ent_polymorphy(dynamic_class, static_ent);
 575         assert(res);
 576
 577         return res;
 578 }
 579
 580
 581
 582 /* ----------------------------------------------------------------------- */
 583 /* Class cast state handling.                                              */
 584 /* ----------------------------------------------------------------------- */
 585
 586 /* - State handling. ----------------------------------------- */
 587
 588 void set_irg_class_cast_state(ir_graph *irg, ir_class_cast_state s) {
 589         if (get_irp_class_cast_state() > s) set_irp_class_cast_state(s);
 590         irg->class_cast_state = s;
 591 }
 592
 593 ir_class_cast_state get_irg_class_cast_state(ir_graph *irg) {
 594         return irg->class_cast_state;
 595 }
 596
 597 void set_irp_class_cast_state(ir_class_cast_state s) {
 598         int i;
 599         for (i = 0; i < get_irp_n_irgs(); ++i)
 600                 assert(get_irg_class_cast_state(get_irp_irg(i)) >= s);
 601         irp->class_cast_state = s;
 602 }
 603
 604 ir_class_cast_state get_irp_class_cast_state(void) {
 605         return irp->class_cast_state;
 606 }
 607
 608 char *get_class_cast_state_string(ir_class_cast_state s) {
 609 #define X(a)    case a: return #a
 610         switch(s) {
 611         X(ir_class_casts_any);
 612         X(ir_class_casts_transitive);
 613         X(ir_class_casts_normalized);
 614         X(ir_class_casts_state_max);
 615         default: return "invalid class cast state";
 616         }
 617 #undef X
 618 }
 619
 620 /* - State verification. ------------------------------------- */
 621
 622 typedef struct ccs_env {
 623         ir_class_cast_state expected_state;
 624         ir_class_cast_state worst_situation;
 625 } ccs_env;
 626
 627 void verify_irn_class_cast_state(ir_node *n, void *env) {
 628         ccs_env             *ccs = (ccs_env *)env;
 629         ir_class_cast_state this_state = ir_class_casts_any;
 630         ir_type             *fromtype, *totype;
 631         int                 ref_depth = 0;
 632
 633         if (get_irn_op(n) != op_Cast) return;
 634
 635         fromtype = get_irn_typeinfo_type(get_Cast_op(n));
 636         totype   = get_Cast_type(n);
 637
 638         while (is_Pointer_type(totype) && is_Pointer_type(fromtype)) {
 639                 totype   = get_pointer_points_to_type(totype);
 640                 fromtype = get_pointer_points_to_type(fromtype);
 641                 ref_depth++;
 642         }
 643
 644         if (!is_Class_type(totype)) return;
 645
 646         if (is_SubClass_of(totype, fromtype) ||
 647                 is_SubClass_of(fromtype, totype)   ) {
 648                 this_state = ir_class_casts_transitive;
 649                 if ((get_class_supertype_index(totype, fromtype) != -1) ||
 650                     (get_class_supertype_index(fromtype, totype) != -1) ||
 651                     fromtype == totype) {
 652                         /*   Das ist doch alt?  Aus dem cvs aufgetaucht ...
 653                         if ((get_class_supertype_index(totype, fromtype) == -1) &&
 654                             (get_class_supertype_index(fromtype, totype) == -1) ) {  */
 655                         this_state = ir_class_casts_normalized;
 656                 }
 657         }
 658
 659         if (!(this_state >= ccs->expected_state)) {
 660                 ir_printf("  Node is %+F\n", n);
 661                 ir_printf("    totype   %+F\n", totype);
 662                 ir_printf("    fromtype %+F\n", fromtype);
 663                 ir_printf("    this_state: %s, exp. state: %s\n",
 664                         get_class_cast_state_string(this_state),
 665                         get_class_cast_state_string(ccs->expected_state));
 666                 assert(this_state >= ccs->expected_state &&
 667                         "invalid state class cast state setting in graph");
 668         }
 669
 670         if (this_state < ccs->worst_situation)
 671                 ccs->worst_situation = this_state;
 672 }
 673
 674
 675 /** Verify that the graph meets requirements of state set. */
 676 void verify_irg_class_cast_state(ir_graph *irg) {
 677         ccs_env env;
 678
 679         env.expected_state  = get_irg_class_cast_state(irg);
 680         env.worst_situation = ir_class_casts_normalized;
 681
 682         irg_walk_graph(irg, NULL, verify_irn_class_cast_state, &env);
 683
 684         if ((env.worst_situation > env.expected_state) && get_firm_verbosity()) {
 685                 ir_printf("Note:  class cast state is set lower than reqired in graph \n\t%+F\n", irg);
 686                 printf("       state is %s, reqired is %s\n",
 687                         get_class_cast_state_string(env.expected_state),
 688                         get_class_cast_state_string(env.worst_situation));
 689         }
 690 }