gcc/analyzer/feasible-graph.h

   1 /* A graph for exploring trees of feasible paths through the egraph.
   2    Copyright (C) 2021-2023 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_FEASIBLE_GRAPH_H
  22 #define GCC_ANALYZER_FEASIBLE_GRAPH_H
  23
  24 #include "analyzer/exploded-graph.h"
  25
  26 namespace ana {
  27
  28 /* Forward decls.  */
  29
  30 class base_feasible_node;
  31   class feasible_node;
  32   class infeasible_node;
  33 class base_feasible_edge;
  34   class feasible_edge;
  35   class infeasible_edge;
  36 class feasible_graph;
  37 class feasible_cluster;
  38
  39 /* A traits class for feasible_graph.  */
  40
  41 struct fg_traits
  42 {
  43   typedef base_feasible_node node_t;
  44   typedef base_feasible_edge edge_t;
  45   typedef feasible_graph graph_t;
  46   struct dump_args_t
  47   {
  48     typedef typename eg_traits::dump_args_t inner_args_t;
  49
  50     dump_args_t (const inner_args_t &inner_args)
  51     : m_inner_args (inner_args)
  52     {
  53     }
  54
  55     const inner_args_t &m_inner_args;
  56   };
  57   typedef feasible_cluster cluster_t;
  58 };
  59
  60 /* Base class of node within a feasible_graph.
  61    There can be 0 or more base_feasible_nodes per exploded_node.  */
  62
  63 class base_feasible_node : public dnode<fg_traits>
  64 {
  65  public:
  66   void dump_dot_id (pretty_printer *pp) const;
  67
  68   const exploded_node *get_inner_node () const { return m_inner_node; }
  69   unsigned get_index () const { return m_index; }
  70
  71  protected:
  72   base_feasible_node (const exploded_node *inner_node, unsigned index)
  73   : m_inner_node (inner_node), m_index (index)
  74   {}
  75
  76   const exploded_node *m_inner_node;
  77   unsigned m_index;
  78 };
  79
  80 /* Subclass of base_feasible_node for a node that is reachable via a
  81    feasible path, with a particular state.  */
  82
  83 class feasible_node : public base_feasible_node
  84 {
  85 public:
  86   feasible_node (const exploded_node *inner_node, unsigned index,
  87                  const feasibility_state &state,
  88                  unsigned path_length)
  89   : base_feasible_node (inner_node, index),
  90     m_state (state),
  91     m_path_length (path_length)
  92   {
  93   }
  94
  95   void dump_dot (graphviz_out *gv,
  96                  const dump_args_t &args) const final override;
  97
  98   const feasibility_state &get_state () const { return m_state; }
  99   const region_model &get_model () const { return m_state.get_model (); }
 100   const auto_sbitmap &get_snodes_visited () const
 101   {
 102     return m_state.get_snodes_visited ();
 103   }
 104
 105   unsigned get_path_length () const { return m_path_length; }
 106
 107   bool get_state_at_stmt (const gimple *target_stmt,
 108                           region_model *out) const;
 109
 110 private:
 111   feasibility_state m_state;
 112   unsigned m_path_length;
 113 };
 114
 115 /* Subclass of base_feasible_node for a node that requires following
 116    an infeasible edge to reach (and thus terminating this part of the
 117    exploration).  */
 118
 119 class infeasible_node : public base_feasible_node
 120 {
 121 public:
 122   infeasible_node (const exploded_node *inner_node, unsigned index,
 123                    rejected_constraint *rc)
 124   : base_feasible_node (inner_node, index),
 125     m_rc (rc)
 126   {
 127   }
 128   ~infeasible_node () { delete m_rc; }
 129
 130   void dump_dot (graphviz_out *gv,
 131                  const dump_args_t &args) const final override;
 132
 133 private:
 134   rejected_constraint *m_rc;
 135 };
 136
 137 /* Base class of edge within a feasible_graph.  */
 138
 139 class base_feasible_edge : public dedge<fg_traits>
 140 {
 141  public:
 142   void dump_dot (graphviz_out *gv,
 143                  const dump_args_t &args) const final override;
 144
 145   const exploded_edge *get_inner_edge () const { return m_inner_edge; }
 146
 147  protected:
 148   base_feasible_edge (base_feasible_node *src, base_feasible_node *dest,
 149                       const exploded_edge *inner_edge)
 150   : dedge<fg_traits> (src, dest), m_inner_edge (inner_edge)
 151   {
 152   }
 153
 154   const exploded_edge *m_inner_edge;
 155 };
 156
 157 /* Subclass of base_feasible_edge for connecting two feasible_nodes.  */
 158
 159 class feasible_edge : public base_feasible_edge
 160 {
 161  public:
 162   feasible_edge (feasible_node *src, feasible_node *dest,
 163                  const exploded_edge *inner_edge)
 164   : base_feasible_edge (src, dest, inner_edge)
 165   {
 166   }
 167 };
 168
 169 /* Subclass of base_feasible_edge for connecting a feasible_node
 170    to an infeasible_node (and thus terminating this part of the
 171    exploration).  */
 172
 173 class infeasible_edge : public base_feasible_edge
 174 {
 175  public:
 176   infeasible_edge (feasible_node *src, infeasible_node *dest,
 177                    const exploded_edge *inner_edge)
 178   : base_feasible_edge (src, dest, inner_edge)
 179   {
 180   }
 181 };
 182
 183 /* A digraph subclass for exploring trees of feasible paths through
 184    the egraph.  This is actually a tree.
 185
 186    The paths within the graph of feasible_nodes express feasible paths
 187    through the graph, and it also captures known infeasible edges,
 188    which is invaluable for debugging.  */
 189
 190 class feasible_graph : public digraph <fg_traits>
 191 {
 192  public:
 193   feasible_graph ();
 194
 195   feasible_node *add_node (const exploded_node *enode,
 196                            const feasibility_state &state,
 197                            unsigned path_length);
 198
 199   void add_feasibility_problem (feasible_node *src_fnode,
 200                                 const exploded_edge *eedge,
 201                                 rejected_constraint *rc);
 202
 203   std::unique_ptr<exploded_path> make_epath (feasible_node *fnode) const;
 204
 205   void dump_feasible_path (const feasible_node &dst_fnode,
 206                            const char *filename) const;
 207
 208   unsigned get_num_infeasible () const { return m_num_infeasible; }
 209
 210   void log_stats (logger *logger) const;
 211
 212 private:
 213   void dump_feasible_path (const feasible_node &dst_fnode,
 214                            pretty_printer *pp) const;
 215
 216   unsigned m_num_infeasible;
 217 };
 218
 219 class feasible_cluster : public cluster <fg_traits>
 220 {
 221 };
 222
 223 } // namespace ana
 224
 225 #endif /* GCC_ANALYZER_FEASIBLE_GRAPH_H */