gcc/analyzer/feasible-graph.cc

   1 /* A graph for exploring trees of feasible paths through the egraph.
   2    Copyright (C) 2021-2022 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 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tree.h"
  26 #include "pretty-print.h"
  27 #include "gcc-rich-location.h"
  28 #include "gimple-pretty-print.h"
  29 #include "function.h"
  30 #include "diagnostic-core.h"
  31 #include "diagnostic-event-id.h"
  32 #include "diagnostic-path.h"
  33 #include "bitmap.h"
  34 #include "ordered-hash-map.h"
  35 #include "analyzer/analyzer.h"
  36 #include "analyzer/analyzer-logging.h"
  37 #include "analyzer/sm.h"
  38 #include "analyzer/pending-diagnostic.h"
  39 #include "analyzer/diagnostic-manager.h"
  40 #include "analyzer/call-string.h"
  41 #include "analyzer/program-point.h"
  42 #include "analyzer/store.h"
  43 #include "analyzer/region-model.h"
  44 #include "analyzer/constraint-manager.h"
  45 #include "cfg.h"
  46 #include "basic-block.h"
  47 #include "gimple.h"
  48 #include "gimple-iterator.h"
  49 #include "cgraph.h"
  50 #include "digraph.h"
  51 #include "analyzer/supergraph.h"
  52 #include "analyzer/program-state.h"
  53 #include "analyzer/exploded-graph.h"
  54 #include "analyzer/feasible-graph.h"
  55
  56 #if ENABLE_ANALYZER
  57
  58 namespace ana {
  59
  60 /* class base_feasible_node : public dnode<fg_traits>.  */
  61
  62 /* Print an id to PP for this node suitable for use in .dot dumps.  */
  63
  64 void
  65 base_feasible_node::dump_dot_id (pretty_printer *pp) const
  66 {
  67   pp_printf (pp, "fnode_%i", m_index);
  68 }
  69
  70 /* class feasible_node : public base_feasible_node.  */
  71
  72 /* Implementation of dump_dot vfunc for feasible_node.  */
  73
  74 void
  75 feasible_node::dump_dot (graphviz_out *gv,
  76                         const dump_args_t &) const
  77 {
  78   pretty_printer *pp = gv->get_pp ();
  79
  80   dump_dot_id (pp);
  81   pp_printf (pp, " [shape=none,margin=0,style=filled,fillcolor=%s,label=\"",
  82              m_inner_node->get_dot_fillcolor ());
  83   pp_write_text_to_stream (pp);
  84
  85   pp_printf (pp, "FN: %i (EN: %i); len=%i", m_index, m_inner_node->m_index,
  86              m_path_length);
  87   pp_newline (pp);
  88
  89   format f (true);
  90   m_inner_node->get_point ().print (pp, f);
  91   pp_newline (pp);
  92
  93   /* Show the model at this point along expansion of the feasible path,
  94      rather than the model within the enode.  */
  95   m_state.get_model ().dump_to_pp (pp, true, true);
  96   pp_newline (pp);
  97
  98   m_inner_node->dump_processed_stmts (pp);
  99   m_inner_node->dump_saved_diagnostics (pp);
 100
 101   pp_write_text_as_dot_label_to_stream (pp, /*for_record=*/true);
 102
 103   pp_string (pp, "\"];\n\n");
 104   pp_flush (pp);
 105 }
 106
 107 /* Implementation of dump_dot vfunc for infeasible_node.
 108    In particular, show the rejected constraint.  */
 109
 110 void
 111 infeasible_node::dump_dot (graphviz_out *gv,
 112                            const dump_args_t &) const
 113 {
 114   pretty_printer *pp = gv->get_pp ();
 115
 116   dump_dot_id (pp);
 117   pp_printf (pp, " [shape=none,margin=0,style=filled,fillcolor=%s,label=\"",
 118              m_inner_node->get_dot_fillcolor ());
 119   pp_write_text_to_stream (pp);
 120
 121   pp_printf (pp, "infeasible edge to EN: %i", m_inner_node->m_index);
 122   pp_newline (pp);
 123
 124   pp_string (pp, "rejected constraint:");
 125   pp_newline (pp);
 126   m_rc->dump_to_pp (pp);
 127
 128   pp_write_text_as_dot_label_to_stream (pp, /*for_record=*/true);
 129
 130   pp_string (pp, "\"];\n\n");
 131   pp_flush (pp);
 132 }
 133
 134 /* class base_feasible_edge : public dedge<fg_traits>.  */
 135
 136 /* Implementation of dump_dot vfunc for base_easible_edge.  */
 137
 138 void
 139 base_feasible_edge::dump_dot (graphviz_out *gv, const dump_args_t &) const
 140 {
 141   pretty_printer *pp = gv->get_pp ();
 142
 143   m_src->dump_dot_id (pp);
 144   pp_string (pp, " -> ");
 145   m_dest->dump_dot_id (pp);
 146
 147   m_inner_edge->dump_dot_label (pp);
 148 }
 149
 150 /* class feasible_graph : public digraph <fg_traits>.  */
 151
 152 /* Ctor for feasible_graph.  */
 153
 154 feasible_graph::feasible_graph ()
 155 : m_num_infeasible (0)
 156 {
 157 }
 158
 159 /* Add a feasible_node to this graph for ENODE, STATE with the
 160    given PATH_LENGTH. */
 161
 162 feasible_node *
 163 feasible_graph::add_node (const exploded_node *enode,
 164                           const feasibility_state &state,
 165                           unsigned path_length)
 166 {
 167   /* We don't attempt get_or_create here.  */
 168   feasible_node *fnode = new feasible_node (enode, m_nodes.length (),
 169                                             state, path_length);
 170   digraph<fg_traits>::add_node (fnode);
 171   return fnode;
 172 }
 173
 174 /* Add an infeasible_node to this graph and an infeasible_edge connecting
 175    to it from SRC_FNODE, capturing a failure of RC along EEDGE.
 176    Takes ownership of RC.  */
 177
 178 void
 179 feasible_graph::add_feasibility_problem (feasible_node *src_fnode,
 180                                          const exploded_edge *eedge,
 181                                          rejected_constraint *rc)
 182 {
 183   infeasible_node *dst_fnode
 184     = new infeasible_node (eedge->m_dest, m_nodes.length (), rc);
 185   digraph<fg_traits>::add_node (dst_fnode);
 186   add_edge (new infeasible_edge (src_fnode, dst_fnode, eedge));
 187   m_num_infeasible++;
 188 }
 189
 190 /* Make an exploded_path from the origin to FNODE's exploded_node,
 191    following the edges in the feasible_graph.  */
 192
 193 std::unique_ptr<exploded_path>
 194 feasible_graph::make_epath (feasible_node *fnode) const
 195 {
 196   std::unique_ptr<exploded_path> epath (new exploded_path ());
 197
 198   /* FG is actually a tree.  Built the path backwards, by walking
 199      backwards from FNODE until we reach the origin.  */
 200   while (fnode->get_inner_node ()->m_index != 0)
 201     {
 202       gcc_assert (fnode->m_preds.length () == 1);
 203       feasible_edge *pred_fedge
 204         = static_cast <feasible_edge *> (fnode->m_preds[0]);
 205       epath->m_edges.safe_push (pred_fedge->get_inner_edge ());
 206       fnode = static_cast <feasible_node *> (pred_fedge->m_src);
 207     }
 208
 209   /* Now reverse it.  */
 210   epath->m_edges.reverse ();
 211
 212   return epath;
 213 }
 214
 215 /* Dump the path to DST_FNODE in textual form to PP.  */
 216
 217 void
 218 feasible_graph::dump_feasible_path (const feasible_node &dst_fnode,
 219                                     pretty_printer *pp) const
 220 {
 221   const feasible_node *fnode = &dst_fnode;
 222
 223   auto_vec<const feasible_edge *> fpath;
 224
 225   /* FG is actually a tree.  Built the path backwards, by walking
 226      backwards from FNODE until we reach the origin.  */
 227   while (fnode->get_inner_node ()->m_index != 0)
 228     {
 229       gcc_assert (fnode->m_preds.length () == 1);
 230       feasible_edge *pred_fedge
 231         = static_cast <feasible_edge *> (fnode->m_preds[0]);
 232       fpath.safe_push (pred_fedge);
 233       fnode = static_cast <const feasible_node *> (pred_fedge->m_src);
 234     }
 235
 236   /* Now reverse it.  */
 237   fpath.reverse ();
 238
 239   for (unsigned i = 0; i < fpath.length (); i++)
 240     {
 241       const feasible_edge *fedge = fpath[i];
 242       const feasible_node *src_fnode
 243         = static_cast <const feasible_node *> (fedge->m_src);
 244       const feasible_node *dest_fnode
 245         = static_cast <const feasible_node *> (fedge->m_dest);
 246
 247       pp_printf (pp, "fpath[%i]: FN %i (EN %i) -> FN %i (EN %i)",
 248                  i,
 249                  src_fnode->get_index (),
 250                  src_fnode->get_inner_node ()->m_index,
 251                  dest_fnode->get_index (),
 252                  dest_fnode->get_inner_node ()->m_index);
 253       pp_newline (pp);
 254       pp_printf (pp, "  FN %i (EN %i):",
 255                  dest_fnode->get_index (),
 256                  dest_fnode->get_inner_node ()->m_index);
 257       pp_newline (pp);
 258       const program_point &point = dest_fnode->get_inner_node ()->get_point ();
 259       point.print (pp, format (true));
 260       dest_fnode->get_state ().dump_to_pp (pp, true, true);
 261       pp_newline (pp);
 262     }
 263 }
 264
 265 /* Dump the path to DST_FNODE in textual form to FILENAME.  */
 266
 267 void
 268 feasible_graph::dump_feasible_path (const feasible_node &dst_fnode,
 269                                     const char *filename) const
 270 {
 271   FILE *fp = fopen (filename, "w");
 272   pretty_printer pp;
 273   pp_format_decoder (&pp) = default_tree_printer;
 274   pp.buffer->stream = fp;
 275   dump_feasible_path (dst_fnode, &pp);
 276   pp_flush (&pp);
 277   fclose (fp);
 278 }
 279
 280 /* Dump stats about this graph to LOGGER.  */
 281
 282 void
 283 feasible_graph::log_stats (logger *logger) const
 284 {
 285   logger->log ("#nodes: %i", m_nodes.length ());
 286   logger->log ("#edges: %i", m_edges.length ());
 287   logger->log ("#feasible nodes: %i", m_nodes.length () - m_num_infeasible);
 288   logger->log ("#feasible edges: %i", m_edges.length () - m_num_infeasible);
 289   logger->log ("#infeasible nodes/edges: %i", m_num_infeasible);
 290 }
 291
 292 } // namespace ana
 293
 294 #endif /* #if ENABLE_ANALYZER */