gcc/analyzer/sm.cc

   1 /* Modeling API uses and misuses via state machines.
   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 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tree.h"
  25 #include "function.h"
  26 #include "basic-block.h"
  27 #include "gimple.h"
  28 #include "options.h"
  29 #include "function.h"
  30 #include "diagnostic-core.h"
  31 #include "pretty-print.h"
  32 #include "analyzer/analyzer.h"
  33 #include "analyzer/analyzer-logging.h"
  34 #include "analyzer/sm.h"
  35
  36 #if ENABLE_ANALYZER
  37
  38 namespace ana {
  39
  40 /* Return true if VAR has pointer or reference type.  */
  41
  42 bool
  43 any_pointer_p (tree var)
  44 {
  45   return POINTER_TYPE_P (TREE_TYPE (var));
  46 }
  47
  48
  49 /* class state_machine::state.  */
  50
  51 /* Base implementation of dump_to_pp vfunc.  */
  52
  53 void
  54 state_machine::state::dump_to_pp (pretty_printer *pp) const
  55 {
  56   pp_string (pp, m_name);
  57 }
  58
  59 /* class state_machine.  */
  60
  61 /* state_machine's ctor.  */
  62
  63 state_machine::state_machine (const char *name, logger *logger)
  64 : log_user (logger), m_name (name), m_next_state_id (0),
  65   m_start (add_state ("start"))
  66 {
  67 }
  68
  69 /* Add a state with name NAME to this state_machine.
  70    The string is required to outlive the state_machine.
  71
  72    Return the state_t for the new state.  */
  73
  74 state_machine::state_t
  75 state_machine::add_state (const char *name)
  76 {
  77   state *s = new state (name, alloc_state_id ());
  78   m_states.safe_push (s);
  79   return s;
  80 }
  81
  82 /* Get the state with name NAME, which must exist.
  83    This is purely intended for use in selftests.  */
  84
  85 state_machine::state_t
  86 state_machine::get_state_by_name (const char *name) const
  87 {
  88   unsigned i;
  89   state *s;
  90   FOR_EACH_VEC_ELT (m_states, i, s)
  91     if (!strcmp (name, s->get_name ()))
  92       return s;
  93   /* Name not found.  */
  94   gcc_unreachable ();
  95 }
  96
  97 /* Dump a multiline representation of this state machine to PP.  */
  98
  99 void
 100 state_machine::dump_to_pp (pretty_printer *pp) const
 101 {
 102   unsigned i;
 103   state *s;
 104   FOR_EACH_VEC_ELT (m_states, i, s)
 105     {
 106       pp_printf (pp, "  state %i: ", i);
 107       s->dump_to_pp (pp);
 108       pp_newline (pp);
 109     }
 110 }
 111
 112 /* Create instances of the various state machines, each using LOGGER,
 113    and populate OUT with them.  */
 114
 115 void
 116 make_checkers (auto_delete_vec <state_machine> &out, logger *logger)
 117 {
 118   out.safe_push (make_malloc_state_machine (logger));
 119   out.safe_push (make_fileptr_state_machine (logger));
 120   /* The "taint" checker must be explicitly enabled (as it currently
 121      leads to state explosions that stop the other checkers working).  */
 122   if (flag_analyzer_checker)
 123     out.safe_push (make_taint_state_machine (logger));
 124   out.safe_push (make_sensitive_state_machine (logger));
 125   out.safe_push (make_signal_state_machine (logger));
 126
 127   /* We only attempt to run the pattern tests if it might have been manually
 128      enabled (for DejaGnu purposes).  */
 129   if (flag_analyzer_checker)
 130     out.safe_push (make_pattern_test_state_machine (logger));
 131
 132   if (flag_analyzer_checker)
 133     {
 134       unsigned read_index, write_index;
 135       state_machine **sm;
 136
 137       /* TODO: this leaks the machines
 138          Would be nice to log the things that were removed.  */
 139       VEC_ORDERED_REMOVE_IF (out, read_index, write_index, sm,
 140                              0 != strcmp (flag_analyzer_checker,
 141                                           (*sm)->get_name ()));
 142     }
 143 }
 144
 145 } // namespace ana
 146
 147 #endif /* #if ENABLE_ANALYZER */