gcc/analyzer/exploded-graph.h

   1 /* Classes for managing a directed graph of <point, state> pairs.
   2    Copyright (C) 2019-2020 Free Software Foundation, Inc.
   3    Contributed by David Malcolm <dmalcolm@redhat.com>.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it
   8 under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful, but
  13 WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef GCC_ANALYZER_EXPLODED_GRAPH_H
  22 #define GCC_ANALYZER_EXPLODED_GRAPH_H
  23
  24 namespace ana {
  25
  26 /* Concrete implementation of region_model_context, wiring it up to the
  27    rest of the analysis engine.  */
  28
  29 class impl_region_model_context : public region_model_context
  30 {
  31  public:
  32   impl_region_model_context (exploded_graph &eg,
  33                              const exploded_node *enode_for_diag,
  34
  35                              /* TODO: should we be getting the ECs from the
  36                                 old state, rather than the new?  */
  37                              const program_state *old_state,
  38                              program_state *new_state,
  39                              state_change *change,
  40
  41                              const gimple *stmt,
  42                              stmt_finder *stmt_finder = NULL);
  43
  44   impl_region_model_context (program_state *state,
  45                              state_change *change,
  46                              const extrinsic_state &ext_state);
  47
  48   void warn (pending_diagnostic *d) FINAL OVERRIDE;
  49
  50   void remap_svalue_ids (const svalue_id_map &map) FINAL OVERRIDE;
  51
  52   int on_svalue_purge (svalue_id first_unused_sid,
  53                        const svalue_id_map &map) FINAL OVERRIDE;
  54
  55   logger *get_logger () FINAL OVERRIDE
  56   {
  57     return m_logger.get_logger ();
  58   }
  59
  60   void on_state_leak (const state_machine &sm,
  61                       int sm_idx,
  62                       svalue_id sid,
  63                       svalue_id first_unused_sid,
  64                       const svalue_id_map &map,
  65                       state_machine::state_t state);
  66
  67   void on_inherited_svalue (svalue_id parent_sid,
  68                             svalue_id child_sid) FINAL OVERRIDE;
  69
  70   void on_cast (svalue_id src_sid,
  71                 svalue_id dst_sid) FINAL OVERRIDE;
  72
  73   void on_condition (tree lhs, enum tree_code op, tree rhs) FINAL OVERRIDE;
  74
  75   void on_unknown_change (svalue_id sid ATTRIBUTE_UNUSED) FINAL OVERRIDE;
  76
  77   void on_phi (const gphi *phi, tree rhs) FINAL OVERRIDE;
  78
  79   void on_unknown_tree_code (path_var pv,
  80                              const dump_location_t &loc) FINAL OVERRIDE;
  81
  82   exploded_graph *m_eg;
  83   log_user m_logger;
  84   const exploded_node *m_enode_for_diag;
  85   const program_state *m_old_state;
  86   program_state *m_new_state;
  87   state_change *m_change;
  88   const gimple *m_stmt;
  89   stmt_finder *m_stmt_finder;
  90   const extrinsic_state &m_ext_state;
  91 };
  92
  93 /* A <program_point, program_state> pair, used internally by
  94    exploded_node as its immutable data, and as a key for identifying
  95    exploded_nodes we've already seen in the graph.  */
  96
  97 class point_and_state
  98 {
  99 public:
 100   point_and_state (const program_point &point,
 101                    const program_state &state)
 102   : m_point (point),
 103     m_state (state),
 104     m_hash (m_point.hash () ^ m_state.hash ())
 105   {
 106     /* We shouldn't be building point_and_states and thus exploded_nodes
 107        for states that aren't valid.  */
 108     gcc_assert (state.m_valid);
 109   }
 110
 111   hashval_t hash () const
 112   {
 113     return m_hash;
 114   }
 115   bool operator== (const point_and_state &other) const
 116   {
 117     return m_point == other.m_point && m_state == other.m_state;
 118   }
 119
 120   const program_point &get_point () const { return m_point; }
 121   const program_state &get_state () const { return m_state; }
 122
 123   void set_state (const program_state &state)
 124   {
 125     m_state = state;
 126     m_hash = m_point.hash () ^ m_state.hash ();
 127   }
 128
 129   void validate (const extrinsic_state &ext_state) const;
 130
 131 private:
 132   program_point m_point;
 133   program_state m_state;
 134   hashval_t m_hash;
 135 };
 136
 137 /* A traits class for exploded graphs and their nodes and edges.  */
 138
 139 struct eg_traits
 140 {
 141   typedef exploded_node node_t;
 142   typedef exploded_edge edge_t;
 143   typedef exploded_graph graph_t;
 144   struct dump_args_t
 145   {
 146     dump_args_t (const exploded_graph &eg) : m_eg (eg) {}
 147     const exploded_graph &m_eg;
 148   };
 149   typedef exploded_cluster cluster_t;
 150 };
 151
 152 /* An exploded_node is a unique, immutable <point, state> pair within the
 153    exploded_graph.
 154    Each exploded_node has a unique index within the graph
 155    (for ease of debugging).  */
 156
 157 class exploded_node : public dnode<eg_traits>
 158 {
 159  public:
 160   /* Has this enode had exploded_graph::process_node called on it?
 161      This allows us to distinguish enodes that were merged during
 162      worklist-handling, and thus never had process_node called on them
 163      (in favor of processing the merged node).  */
 164   enum status
 165   {
 166     /* Node is in the worklist.  */
 167     STATUS_WORKLIST,
 168
 169     /* Node has had exploded_graph::process_node called on it.  */
 170     STATUS_PROCESSED,
 171
 172     /* Node was left unprocessed due to merger; it won't have had
 173        exploded_graph::process_node called on it.  */
 174     STATUS_MERGER
 175   };
 176
 177   exploded_node (point_and_state ps,
 178                  int index)
 179   : m_ps (ps), m_status (STATUS_WORKLIST), m_index (index)
 180   {
 181     gcc_checking_assert (ps.get_state ().m_region_model->canonicalized_p ());
 182   }
 183
 184   hashval_t hash () const { return m_ps.hash (); }
 185
 186   void dump_dot (graphviz_out *gv, const dump_args_t &args)
 187     const FINAL OVERRIDE;
 188   void dump_dot_id (pretty_printer *pp) const;
 189
 190   void dump_to_pp (pretty_printer *pp, const extrinsic_state &ext_state) const;
 191   void dump (FILE *fp, const extrinsic_state &ext_state) const;
 192   void dump (const extrinsic_state &ext_state) const;
 193
 194   /* The result of on_stmt.  */
 195   struct on_stmt_flags
 196   {
 197     on_stmt_flags (bool sm_changes)
 198     : m_sm_changes (sm_changes),
 199       m_terminate_path (false)
 200     {}
 201
 202     static on_stmt_flags terminate_path ()
 203     {
 204       return on_stmt_flags (true, true);
 205     }
 206
 207     static on_stmt_flags state_change (bool any_sm_changes)
 208     {
 209       return on_stmt_flags (any_sm_changes, false);
 210     }
 211
 212     /* Did any sm-changes occur handling the stmt.  */
 213     bool m_sm_changes : 1;
 214
 215     /* Should we stop analyzing this path (on_stmt may have already
 216        added nodes/edges, e.g. when handling longjmp).  */
 217     bool m_terminate_path : 1;
 218
 219   private:
 220     on_stmt_flags (bool sm_changes,
 221                    bool terminate_path)
 222     : m_sm_changes (sm_changes),
 223       m_terminate_path (terminate_path)
 224     {}
 225   };
 226
 227   on_stmt_flags on_stmt (exploded_graph &eg,
 228                          const supernode *snode,
 229                          const gimple *stmt,
 230                          program_state *state,
 231                          state_change *change) const;
 232   bool on_edge (exploded_graph &eg,
 233                 const superedge *succ,
 234                 program_point *next_point,
 235                 program_state *next_state,
 236                 state_change *change) const;
 237   void on_longjmp (exploded_graph &eg,
 238                    const gcall *call,
 239                    program_state *new_state,
 240                    region_model_context *ctxt) const;
 241
 242   void detect_leaks (exploded_graph &eg) const;
 243
 244   const program_point &get_point () const { return m_ps.get_point (); }
 245   const supernode *get_supernode () const
 246   {
 247     return get_point ().get_supernode ();
 248   }
 249   function *get_function () const
 250   {
 251     return get_point ().get_function ();
 252   }
 253   int get_stack_depth () const
 254   {
 255     return get_point ().get_stack_depth ();
 256   }
 257   const gimple *get_stmt () const { return get_point ().get_stmt (); }
 258
 259   const program_state &get_state () const { return m_ps.get_state (); }
 260
 261   const point_and_state *get_ps_key () const { return &m_ps; }
 262   const program_point *get_point_key () const { return &m_ps.get_point (); }
 263
 264   void dump_succs_and_preds (FILE *outf) const;
 265
 266   enum status get_status () const { return m_status; }
 267   void set_status (enum status status)
 268   {
 269     gcc_assert (m_status == STATUS_WORKLIST);
 270     m_status = status;
 271   }
 272
 273 private:
 274   DISABLE_COPY_AND_ASSIGN (exploded_node);
 275
 276   const char * get_dot_fillcolor () const;
 277
 278   /* The <program_point, program_state> pair.  This is const, as it
 279      is immutable once the exploded_node has been created.  */
 280   const point_and_state m_ps;
 281
 282   enum status m_status;
 283
 284 public:
 285   /* The index of this exploded_node.  */
 286   const int m_index;
 287 };
 288
 289 /* An edge within the exploded graph.
 290    Some exploded_edges have an underlying superedge; others don't.  */
 291
 292 class exploded_edge : public dedge<eg_traits>
 293 {
 294  public:
 295   /* Abstract base class for associating custom data with an
 296      exploded_edge, for handling non-standard edges such as
 297      rewinding from a longjmp, signal handlers, etc.  */
 298   class custom_info_t
 299   {
 300   public:
 301     virtual ~custom_info_t () {}
 302
 303     /* Hook for making .dot label more readable .  */
 304     virtual void print (pretty_printer *pp) = 0;
 305
 306     /* Hook for updating MODEL within exploded_path::feasible_p.  */
 307     virtual void update_model (region_model *model,
 308                                const exploded_edge &eedge) = 0;
 309
 310     virtual void add_events_to_path (checker_path *emission_path,
 311                                      const exploded_edge &eedge) = 0;
 312   };
 313
 314   exploded_edge (exploded_node *src, exploded_node *dest,
 315                  const extrinsic_state &ext_state,
 316                  const superedge *sedge,
 317                  const state_change &change,
 318                  custom_info_t *custom_info);
 319   ~exploded_edge ();
 320   void dump_dot (graphviz_out *gv, const dump_args_t &args)
 321     const FINAL OVERRIDE;
 322
 323   //private:
 324   const superedge *const m_sedge;
 325
 326   const state_change m_change;
 327
 328   /* NULL for most edges; will be non-NULL for special cases
 329      such as an unwind from a longjmp to a setjmp, or when
 330      a signal is delivered to a signal-handler.
 331
 332      Owned by this class.  */
 333   custom_info_t *m_custom_info;
 334
 335 private:
 336   DISABLE_COPY_AND_ASSIGN (exploded_edge);
 337 };
 338
 339 /* Extra data for an exploded_edge that represents a rewind from a
 340    longjmp to a setjmp (or from a siglongjmp to a sigsetjmp).  */
 341
 342 class rewind_info_t : public exploded_edge::custom_info_t
 343 {
 344 public:
 345   rewind_info_t (const setjmp_record &setjmp_record,
 346                  const gcall *longjmp_call)
 347   : m_setjmp_record (setjmp_record),
 348     m_longjmp_call (longjmp_call)
 349   {}
 350
 351   void print (pretty_printer *pp) FINAL OVERRIDE
 352   {
 353     pp_string (pp, "rewind");
 354   }
 355
 356   void update_model (region_model *model,
 357                      const exploded_edge &eedge) FINAL OVERRIDE;
 358
 359   void add_events_to_path (checker_path *emission_path,
 360                            const exploded_edge &eedge) FINAL OVERRIDE;
 361
 362   const program_point &get_setjmp_point () const
 363   {
 364     const program_point &origin_point = get_enode_origin ()->get_point ();
 365
 366     /* "origin_point" ought to be before the call to "setjmp".  */
 367     gcc_assert (origin_point.get_kind () == PK_BEFORE_STMT);
 368
 369     /* TODO: assert that it's the final stmt in its supernode.  */
 370
 371     return origin_point;
 372   }
 373
 374   const gcall *get_setjmp_call () const
 375   {
 376     return m_setjmp_record.m_setjmp_call;
 377   }
 378
 379   const gcall *get_longjmp_call () const
 380   {
 381     return m_longjmp_call;
 382   }
 383
 384   const exploded_node *get_enode_origin () const
 385   {
 386     return m_setjmp_record.m_enode;
 387   }
 388
 389 private:
 390   setjmp_record m_setjmp_record;
 391   const gcall *m_longjmp_call;
 392 };
 393
 394 /* Statistics about aspects of an exploded_graph.  */
 395
 396 struct stats
 397 {
 398   stats (int num_supernodes);
 399   void log (logger *logger) const;
 400   void dump (FILE *out) const;
 401
 402   int m_num_nodes[NUM_POINT_KINDS];
 403   int m_node_reuse_count;
 404   int m_node_reuse_after_merge_count;
 405   int m_num_supernodes;
 406 };
 407
 408 /* Traits class for ensuring uniqueness of point_and_state data within
 409    an exploded_graph.  */
 410
 411 struct eg_hash_map_traits
 412 {
 413   typedef const point_and_state *key_type;
 414   typedef exploded_node *value_type;
 415   typedef exploded_node *compare_type;
 416
 417   static inline hashval_t hash (const key_type &k)
 418   {
 419     gcc_assert (k != NULL);
 420     gcc_assert (k != reinterpret_cast<key_type> (1));
 421     return k->hash ();
 422   }
 423   static inline bool equal_keys (const key_type &k1, const key_type &k2)
 424   {
 425     gcc_assert (k1 != NULL);
 426     gcc_assert (k2 != NULL);
 427     gcc_assert (k1 != reinterpret_cast<key_type> (1));
 428     gcc_assert (k2 != reinterpret_cast<key_type> (1));
 429     if (k1 && k2)
 430       return *k1 == *k2;
 431     else
 432       /* Otherwise they must both be non-NULL.  */
 433       return k1 == k2;
 434   }
 435   template <typename T>
 436   static inline void remove (T &)
 437   {
 438     /* empty; the nodes are handled elsewhere.  */
 439   }
 440   template <typename T>
 441   static inline void mark_deleted (T &entry)
 442   {
 443     entry.m_key = reinterpret_cast<key_type> (1);
 444   }
 445   template <typename T>
 446   static inline void mark_empty (T &entry)
 447   {
 448     entry.m_key = NULL;
 449   }
 450   template <typename T>
 451   static inline bool is_deleted (const T &entry)
 452   {
 453     return entry.m_key == reinterpret_cast<key_type> (1);
 454   }
 455   template <typename T>
 456   static inline bool is_empty (const T &entry)
 457   {
 458     return entry.m_key == NULL;
 459   }
 460   static const bool empty_zero_p = false;
 461 };
 462
 463 /* Per-program_point data for an exploded_graph.  */
 464
 465 struct per_program_point_data
 466 {
 467   per_program_point_data (const program_point &key)
 468   : m_key (key)
 469   {}
 470
 471   const program_point m_key;
 472   auto_vec<exploded_node *> m_enodes;
 473 };
 474
 475 /* Traits class for storing per-program_point data within
 476    an exploded_graph.  */
 477
 478 struct eg_point_hash_map_traits
 479 {
 480   typedef const program_point *key_type;
 481   typedef per_program_point_data *value_type;
 482   typedef per_program_point_data *compare_type;
 483
 484   static inline hashval_t hash (const key_type &k)
 485   {
 486     gcc_assert (k != NULL);
 487     gcc_assert (k != reinterpret_cast<key_type> (1));
 488     return k->hash ();
 489   }
 490   static inline bool equal_keys (const key_type &k1, const key_type &k2)
 491   {
 492     gcc_assert (k1 != NULL);
 493     gcc_assert (k2 != NULL);
 494     gcc_assert (k1 != reinterpret_cast<key_type> (1));
 495     gcc_assert (k2 != reinterpret_cast<key_type> (1));
 496     if (k1 && k2)
 497       return *k1 == *k2;
 498     else
 499       /* Otherwise they must both be non-NULL.  */
 500       return k1 == k2;
 501   }
 502   template <typename T>
 503   static inline void remove (T &)
 504   {
 505     /* empty; the nodes are handled elsewhere.  */
 506   }
 507   template <typename T>
 508   static inline void mark_deleted (T &entry)
 509   {
 510     entry.m_key = reinterpret_cast<key_type> (1);
 511   }
 512   template <typename T>
 513   static inline void mark_empty (T &entry)
 514   {
 515     entry.m_key = NULL;
 516   }
 517   template <typename T>
 518   static inline bool is_deleted (const T &entry)
 519   {
 520     return entry.m_key == reinterpret_cast<key_type> (1);
 521   }
 522   template <typename T>
 523   static inline bool is_empty (const T &entry)
 524   {
 525     return entry.m_key == NULL;
 526   }
 527   static const bool empty_zero_p = false;
 528 };
 529
 530 /* Data about a particular call_string within an exploded_graph.  */
 531
 532 struct per_call_string_data
 533 {
 534   per_call_string_data (const call_string &key, int num_supernodes)
 535   : m_key (key), m_stats (num_supernodes)
 536   {}
 537
 538   const call_string m_key;
 539   stats m_stats;
 540 };
 541
 542 /* Traits class for storing per-call_string data within
 543    an exploded_graph.  */
 544
 545 struct eg_call_string_hash_map_traits
 546 {
 547   typedef const call_string *key_type;
 548   typedef per_call_string_data *value_type;
 549   typedef per_call_string_data *compare_type;
 550
 551   static inline hashval_t hash (const key_type &k)
 552   {
 553     gcc_assert (k != NULL);
 554     gcc_assert (k != reinterpret_cast<key_type> (1));
 555     return k->hash ();
 556   }
 557   static inline bool equal_keys (const key_type &k1, const key_type &k2)
 558   {
 559     gcc_assert (k1 != NULL);
 560     gcc_assert (k2 != NULL);
 561     gcc_assert (k1 != reinterpret_cast<key_type> (1));
 562     gcc_assert (k2 != reinterpret_cast<key_type> (1));
 563     if (k1 && k2)
 564       return *k1 == *k2;
 565     else
 566       /* Otherwise they must both be non-NULL.  */
 567       return k1 == k2;
 568   }
 569   template <typename T>
 570   static inline void remove (T &)
 571   {
 572     /* empty; the nodes are handled elsewhere.  */
 573   }
 574   template <typename T>
 575   static inline void mark_deleted (T &entry)
 576   {
 577     entry.m_key = reinterpret_cast<key_type> (1);
 578   }
 579   template <typename T>
 580   static inline void mark_empty (T &entry)
 581   {
 582     entry.m_key = NULL;
 583   }
 584   template <typename T>
 585   static inline bool is_deleted (const T &entry)
 586   {
 587     return entry.m_key == reinterpret_cast<key_type> (1);
 588   }
 589   template <typename T>
 590   static inline bool is_empty (const T &entry)
 591   {
 592     return entry.m_key == NULL;
 593   }
 594   static const bool empty_zero_p = false;
 595 };
 596
 597 /* Data about a particular function within an exploded_graph.  */
 598
 599 struct per_function_data
 600 {
 601   per_function_data () {}
 602
 603   void add_call_summary (exploded_node *node)
 604   {
 605     m_summaries.safe_push (node);
 606   }
 607
 608   auto_vec<exploded_node *> m_summaries;
 609 };
 610
 611
 612 /* The strongly connected components of a supergraph.
 613    In particular, this allows us to compute a partial ordering
 614    of supernodes.  */
 615
 616 class strongly_connected_components
 617 {
 618 public:
 619   strongly_connected_components (const supergraph &sg, logger *logger);
 620
 621   int get_scc_id (int node_index) const
 622   {
 623     return m_per_node[node_index].m_lowlink;
 624   }
 625
 626   void dump () const;
 627
 628 private:
 629   struct per_node_data
 630   {
 631     per_node_data ()
 632       : m_index (-1), m_lowlink (-1), m_on_stack (false)
 633     {}
 634
 635     int m_index;
 636     int m_lowlink;
 637     bool m_on_stack;
 638   };
 639
 640   void strong_connect (unsigned index);
 641
 642   const supergraph &m_sg;
 643   auto_vec<unsigned> m_stack;
 644   auto_vec<per_node_data> m_per_node;
 645 };
 646
 647 /* The worklist of exploded_node instances that have been added to
 648    an exploded_graph, but that haven't yet been processed to find
 649    their successors (or warnings).
 650
 651    The enodes are stored in a priority queue, ordered by a topological
 652    sort of the SCCs in the supergraph, so that enodes for the same
 653    program_point should appear at the front of the queue together.
 654    This allows for state-merging at CFG join-points, so that
 655    sufficiently-similar enodes can be merged into one.  */
 656
 657 class worklist
 658 {
 659 public:
 660   worklist (const exploded_graph &eg, const analysis_plan &plan);
 661   unsigned length () const;
 662   exploded_node *take_next ();
 663   exploded_node *peek_next ();
 664   void add_node (exploded_node *enode);
 665
 666 private:
 667   class key_t
 668   {
 669   public:
 670     key_t (const worklist &w, exploded_node *enode)
 671     : m_worklist (w), m_enode (enode)
 672     {}
 673
 674     bool operator< (const key_t &other) const
 675     {
 676       return cmp (*this, other) < 0;
 677     }
 678
 679     bool operator== (const key_t &other) const
 680     {
 681       return cmp (*this, other) == 0;
 682     }
 683
 684     bool operator> (const key_t &other) const
 685     {
 686       return !(*this == other || *this < other);
 687     }
 688
 689   private:
 690     static int cmp (const key_t &ka, const key_t &kb);
 691
 692     int get_scc_id (const exploded_node *enode) const
 693     {
 694       const supernode *snode = enode->get_supernode ();
 695       if (snode == NULL)
 696         return 0;
 697       return m_worklist.m_scc.get_scc_id (snode->m_index);
 698     }
 699
 700     const worklist &m_worklist;
 701     exploded_node *m_enode;
 702   };
 703
 704   /* The order is important here: m_scc needs to stick around
 705      until after m_queue has finished being cleaned up (the dtor
 706      calls the ordering fns).  */
 707   const exploded_graph &m_eg;
 708   strongly_connected_components m_scc;
 709   const analysis_plan &m_plan;
 710
 711   /* Priority queue, backed by a fibonacci_heap.  */
 712   typedef fibonacci_heap<key_t, exploded_node> queue_t;
 713   queue_t m_queue;
 714 };
 715
 716 /* An exploded_graph is a directed graph of unique <point, state> pairs.
 717    It also has a worklist of nodes that are waiting for their successors
 718    to be added to the graph.  */
 719
 720 class exploded_graph : public digraph<eg_traits>
 721 {
 722 public:
 723   typedef hash_map <const call_string *, per_call_string_data *,
 724                     eg_call_string_hash_map_traits> call_string_data_map_t;
 725
 726   exploded_graph (const supergraph &sg, logger *logger,
 727                   const extrinsic_state &ext_state,
 728                   const state_purge_map *purge_map,
 729                   const analysis_plan &plan,
 730                   int verbosity);
 731   ~exploded_graph ();
 732
 733   logger *get_logger () const { return m_logger.get_logger (); }
 734
 735   const supergraph &get_supergraph () const { return m_sg; }
 736   const extrinsic_state &get_ext_state () const { return m_ext_state; }
 737   const state_purge_map *get_purge_map () const { return m_purge_map; }
 738   const analysis_plan &get_analysis_plan () const { return m_plan; }
 739
 740   exploded_node *get_origin () const { return m_origin; }
 741
 742   exploded_node *add_function_entry (function *fun);
 743
 744   void build_initial_worklist ();
 745   void process_worklist ();
 746   void process_node (exploded_node *node);
 747
 748   exploded_node *get_or_create_node (const program_point &point,
 749                                      const program_state &state,
 750                                      state_change *change);
 751   exploded_edge *add_edge (exploded_node *src, exploded_node *dest,
 752                            const superedge *sedge,
 753                            const state_change &change,
 754                            exploded_edge::custom_info_t *custom = NULL);
 755
 756   per_program_point_data *
 757   get_or_create_per_program_point_data (const program_point &);
 758
 759   per_call_string_data *
 760   get_or_create_per_call_string_data (const call_string &);
 761
 762   per_function_data *
 763   get_or_create_per_function_data (function *);
 764   per_function_data *get_per_function_data (function *) const;
 765
 766   void save_diagnostic (const state_machine &sm,
 767                         const exploded_node *enode,
 768                         const supernode *node, const gimple *stmt,
 769                         stmt_finder *finder,
 770                         tree var, state_machine::state_t state,
 771                         pending_diagnostic *d);
 772
 773   diagnostic_manager &get_diagnostic_manager ()
 774   {
 775     return m_diagnostic_manager;
 776   }
 777   const diagnostic_manager &get_diagnostic_manager () const
 778   {
 779     return m_diagnostic_manager;
 780   }
 781
 782   stats *get_global_stats () { return &m_global_stats; }
 783   stats *get_or_create_function_stats (function *fn);
 784   void log_stats () const;
 785   void dump_stats (FILE *) const;
 786   void dump_states_for_supernode (FILE *, const supernode *snode) const;
 787   void dump_exploded_nodes () const;
 788
 789   const call_string_data_map_t *get_per_call_string_data () const
 790   { return &m_per_call_string_data; }
 791
 792 private:
 793   DISABLE_COPY_AND_ASSIGN (exploded_graph);
 794
 795   const supergraph &m_sg;
 796
 797   log_user m_logger;
 798
 799   /* Map from point/state to exploded node.
 800      To avoid duplication we store point_and_state
 801      *pointers* as keys, rather than point_and_state, using the
 802      instance from within the exploded_node, with a custom hasher.  */
 803   typedef hash_map <const point_and_state *, exploded_node *,
 804                     eg_hash_map_traits> map_t;
 805   map_t m_point_and_state_to_node;
 806
 807   /* Map from program_point to per-program_point data.  */
 808   typedef hash_map <const program_point *, per_program_point_data *,
 809                     eg_point_hash_map_traits> point_map_t;
 810   point_map_t m_per_point_data;
 811
 812   worklist m_worklist;
 813
 814   exploded_node *m_origin;
 815
 816   const extrinsic_state &m_ext_state;
 817
 818   const state_purge_map *const m_purge_map;
 819
 820   const analysis_plan &m_plan;
 821
 822   typedef hash_map<function *, per_function_data *> per_function_data_t;
 823   per_function_data_t m_per_function_data;
 824
 825   diagnostic_manager m_diagnostic_manager;
 826
 827   /* Stats.  */
 828   stats m_global_stats;
 829   typedef ordered_hash_map<function *, stats *> function_stat_map_t;
 830   function_stat_map_t m_per_function_stats;
 831   stats m_functionless_stats;
 832
 833   call_string_data_map_t m_per_call_string_data;
 834
 835   auto_vec<int> m_PK_AFTER_SUPERNODE_per_snode;
 836 };
 837
 838 /* A path within an exploded_graph: a sequence of edges.  */
 839
 840 class exploded_path
 841 {
 842 public:
 843   exploded_path () : m_edges () {}
 844   exploded_path (const exploded_path &other);
 845   exploded_path & operator= (const exploded_path &other);
 846
 847   unsigned length () const { return m_edges.length (); }
 848
 849   bool find_stmt_backwards (const gimple *search_stmt,
 850                             int *out_idx) const;
 851
 852   exploded_node *get_final_enode () const;
 853
 854   void dump_to_pp (pretty_printer *pp) const;
 855   void dump (FILE *fp) const;
 856   void dump () const;
 857
 858   bool feasible_p (logger *logger) const;
 859
 860   auto_vec<const exploded_edge *> m_edges;
 861 };
 862
 863 /* Finding the shortest exploded_path within an exploded_graph.  */
 864
 865 typedef shortest_paths<eg_traits, exploded_path> shortest_exploded_paths;
 866
 867 /* Abstract base class for use when passing NULL as the stmt for
 868    a possible warning, allowing the choice of stmt to be deferred
 869    until after we have an emission path (and know we're emitting a
 870    warning).  */
 871
 872 class stmt_finder
 873 {
 874 public:
 875   virtual ~stmt_finder () {}
 876   virtual stmt_finder *clone () const = 0;
 877   virtual const gimple *find_stmt (const exploded_path &epath) = 0;
 878 };
 879
 880 // TODO: split the above up?
 881
 882 } // namespace ana
 883
 884 #endif /* GCC_ANALYZER_EXPLODED_GRAPH_H */