gcc/analyzer/trimmed-graph.cc

   1 /* Trimming an exploded graph to a subset of nodes and edges.
   2    Copyright (C) 2021-2024 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 #include "config.h"
  22 #define INCLUDE_MEMORY
  23 #define INCLUDE_VECTOR
  24 #include "system.h"
  25 #include "coretypes.h"
  26 #include "tree.h"
  27 #include "pretty-print.h"
  28 #include "gcc-rich-location.h"
  29 #include "gimple-pretty-print.h"
  30 #include "function.h"
  31 #include "diagnostic-core.h"
  32 #include "diagnostic-event-id.h"
  33 #include "diagnostic-path.h"
  34 #include "bitmap.h"
  35 #include "ordered-hash-map.h"
  36 #include "analyzer/analyzer.h"
  37 #include "analyzer/analyzer-logging.h"
  38 #include "analyzer/sm.h"
  39 #include "analyzer/pending-diagnostic.h"
  40 #include "analyzer/diagnostic-manager.h"
  41 #include "analyzer/call-string.h"
  42 #include "analyzer/program-point.h"
  43 #include "analyzer/store.h"
  44 #include "analyzer/region-model.h"
  45 #include "analyzer/constraint-manager.h"
  46 #include "analyzer/supergraph.h"
  47 #include "analyzer/program-state.h"
  48 #include "analyzer/exploded-graph.h"
  49 #include "analyzer/trimmed-graph.h"
  50
  51 #if ENABLE_ANALYZER
  52
  53 namespace ana {
  54
  55 /* class trimmed_node : public dnode<tg_traits>.  */
  56
  57 /* Implementation of dump_dot vfunc, delegating to the inner node.  */
  58
  59 void
  60 trimmed_node::dump_dot (graphviz_out *gv,
  61                         const dump_args_t &args) const
  62 {
  63   m_inner_node->dump_dot (gv, args.m_inner_args);
  64 }
  65
  66 /* class trimmed_edge : public dedge<tg_traits>.  */
  67
  68 /* trimmed_edge's ctor.  */
  69
  70 trimmed_edge::trimmed_edge (trimmed_node *src, trimmed_node *dest,
  71                             const exploded_edge *inner_edge)
  72 : dedge<tg_traits> (src, dest), m_inner_edge (inner_edge)
  73 {
  74 }
  75
  76 /* Implementation of dump_dot vfunc, delegating to the inner edge.  */
  77
  78 void
  79 trimmed_edge::dump_dot (graphviz_out *gv, const dump_args_t &args) const
  80 {
  81   m_inner_edge->dump_dot (gv, args.m_inner_args);
  82 }
  83
  84 /* class trimmed_graph : public digraph <tg_traits>.  */
  85
  86 /* Ctor for trimmed_graph: construct a graph equivalent to trimming
  87    INNER_GRAPH to all nodes that can reach INNER_DST_NODE.  */
  88
  89 trimmed_graph::trimmed_graph (const exploded_graph &inner_graph,
  90                               const exploded_node *inner_dst_node)
  91 : m_enodes (), m_eedges ()
  92 {
  93   /* Determine what subset of nodes and edges to include in the
  94      trimmed graph.
  95      Walk backwards from INNER_DST_NODE, finding nodes that reach it,
  96      iteratively building the set of nodes and edges.  */
  97   auto_vec <const exploded_node *> worklist;
  98   worklist.safe_push (inner_dst_node);
  99   m_enodes.add (inner_dst_node);
 100   while (worklist.length () > 0)
 101     {
 102       const exploded_node *inner_node = worklist.pop ();
 103       exploded_edge *inner_pred;
 104       unsigned i;
 105       FOR_EACH_VEC_ELT (inner_node->m_preds, i, inner_pred)
 106         {
 107           if (!m_enodes.contains (inner_pred->m_src))
 108             {
 109               worklist.safe_push (inner_pred->m_src);
 110               m_enodes.add (inner_pred->m_src);
 111             }
 112           m_eedges.add (inner_pred);
 113         }
 114     }
 115
 116   /* Create trimmed nodes for all enodes in the set.  */
 117   {
 118     /* Iterate over the vec rather than the hash_set
 119        to ensure deterministic order.  */
 120     exploded_node *inner_node;
 121     unsigned i;
 122     FOR_EACH_VEC_ELT (inner_graph.m_nodes, i, inner_node)
 123       if (m_enodes.contains (inner_node))
 124         {
 125           trimmed_node *tnode = new trimmed_node (inner_node);
 126           add_node (tnode);
 127           m_map_from_enode_to_tnode.put (inner_node, tnode);
 128         }
 129   }
 130
 131   /* Create trimmed edges for all edges in the set.  */
 132   {
 133     /* Iterate over the vec rather than the hash_set
 134        to ensure deterministic order.  */
 135     exploded_edge *inner_edge;
 136     unsigned i;
 137     FOR_EACH_VEC_ELT (inner_graph.m_edges, i, inner_edge)
 138       if (m_eedges.contains (inner_edge))
 139         {
 140           const exploded_node *inner_src = inner_edge->m_src;
 141           const exploded_node *inner_dest = inner_edge->m_dest;
 142           trimmed_node *tsrc = *m_map_from_enode_to_tnode.get (inner_src);
 143           trimmed_node *tdest = *m_map_from_enode_to_tnode.get (inner_dest);
 144           trimmed_edge *tedge = new trimmed_edge (tsrc, tdest, inner_edge);
 145           add_edge (tedge);
 146         }
 147   }
 148 }
 149
 150 /* Dump stats about this graph to LOGGER.  */
 151
 152 void
 153 trimmed_graph::log_stats (logger *logger) const
 154 {
 155   logger->log ("#nodes: %i", m_nodes.length ());
 156   logger->log ("#edges: %i", m_edges.length ());
 157 }
 158
 159 } // namespace ana
 160
 161 #endif /* #if ENABLE_ANALYZER */