gcc/analyzer/region-model-reachability.h

   1 /* Finding reachable regions and values.
   2    Copyright (C) 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_REGION_MODEL_REACHABILITY_H
  22 #define GCC_ANALYZER_REGION_MODEL_REACHABILITY_H
  23
  24 namespace ana {
  25
  26 /* A class for determining which regions and svalues are reachable.
  27
  28    Used by region_model::handle_unrecognized_call for keeping
  29    track of all regions that are reachable, and, of those, which are
  30    mutable.
  31
  32    Used by program_state::detect_leaks
  33    (via region_model::get_reachable_svalues) for detecting leaks.  */
  34
  35 class reachable_regions
  36 {
  37 public:
  38   reachable_regions (store *store, region_model_manager *mgr);
  39
  40   /* Callback called for each cluster when initializing this object.  */
  41   static void init_cluster_cb (const region *base_reg,
  42                                reachable_regions *this_ptr);
  43
  44   /* Called for each cluster when initializing this object.  */
  45   void init_cluster (const region *base_reg);
  46
  47   /* Lazily mark the cluster containing REG as being reachable, recursively
  48      adding clusters reachable from REG's cluster.  */
  49   void add (const region *reg, bool is_mutable);
  50
  51   static void handle_sval_cb (const svalue *sval,
  52                               reachable_regions *this_ptr);
  53
  54   /* Add SVAL.  If it is a pointer, add the pointed-to region.  */
  55   void handle_sval (const svalue *sval);
  56
  57   /* Add SVAL.  If it is a pointer, add the pointed-to region.
  58      Use PARAM_TYPE for determining mutability.  */
  59   void handle_parm (const svalue *sval, tree param_type);
  60
  61   /* Update the store to mark the clusters that were found to be mutable
  62      as having escaped.  */
  63   void mark_escaped_clusters ();
  64
  65   /* Iteration over reachable base regions.  */
  66   hash_set<const region *>::iterator begin ()
  67   {
  68     return m_reachable_base_regs.begin ();
  69   }
  70   hash_set<const region *>::iterator end ()
  71   {
  72     return m_reachable_base_regs.end ();
  73   }
  74
  75   svalue_set::iterator begin_reachable_svals ()
  76   {
  77     return m_reachable_svals.begin ();
  78   }
  79   svalue_set::iterator end_reachable_svals ()
  80   {
  81     return m_reachable_svals.end ();
  82   }
  83   svalue_set::iterator begin_mutable_svals ()
  84   {
  85     return m_mutable_svals.begin ();
  86   }
  87   svalue_set::iterator end_mutable_svals ()
  88   {
  89     return m_mutable_svals.end ();
  90   }
  91
  92   void dump_to_pp (pretty_printer *pp) const;
  93
  94   DEBUG_FUNCTION void dump () const;
  95
  96 private:
  97   store *m_store;
  98   region_model_manager *m_mgr;
  99
 100   /* The base regions already seen.  */
 101   hash_set<const region *> m_reachable_base_regs;
 102
 103   /* The base regions that can be changed (accessed via non-const pointers).  */
 104   hash_set<const region *> m_mutable_base_regs;
 105
 106   /* svalues that were passed as const pointers, so e.g. couldn't have
 107      been freed (but could have e.g. had "close" called on them if an
 108      int file-descriptor).  */
 109   svalue_set m_reachable_svals;
 110   /* svalues that were passed as non-const pointers, so e.g. could have
 111      been freed.  */
 112   svalue_set m_mutable_svals;
 113 };
 114
 115 } // namespace ana
 116
 117 #endif /* GCC_ANALYZER_REGION_MODEL_REACHABILITY_H */