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 /* Add a state with name NAME to this state_machine.
  49    The string is required to outlive the state_machine.
  50
  51    Return the state_t for the new state.  */
  52
  53 state_machine::state_t
  54 state_machine::add_state (const char *name)
  55 {
  56   m_state_names.safe_push (name);
  57   return m_state_names.length () - 1;
  58 }
  59
  60 /* Get the name of state S within this state_machine.  */
  61
  62 const char *
  63 state_machine::get_state_name (state_t s) const
  64 {
  65   return m_state_names[s];
  66 }
  67
  68 /* Get the state with name NAME, which must exist.
  69    This is purely intended for use in selftests.  */
  70
  71 state_machine::state_t
  72 state_machine::get_state_by_name (const char *name)
  73 {
  74   unsigned i;
  75   const char *iter_name;
  76   FOR_EACH_VEC_ELT (m_state_names, i, iter_name)
  77     if (!strcmp (name, iter_name))
  78       return i;
  79   /* Name not found.  */
  80   gcc_unreachable ();
  81 }
  82
  83 /* Assert that S is a valid state for this state_machine.  */
  84
  85 void
  86 state_machine::validate (state_t s) const
  87 {
  88   gcc_assert (s < m_state_names.length ());
  89 }
  90
  91 /* Dump a multiline representation of this state machine to PP.  */
  92
  93 void
  94 state_machine::dump_to_pp (pretty_printer *pp) const
  95 {
  96   unsigned i;
  97   const char *name;
  98   FOR_EACH_VEC_ELT (m_state_names, i, name)
  99     pp_printf (pp, "  state %i: %qs\n", i, name);
 100 }
 101
 102 /* Create instances of the various state machines, each using LOGGER,
 103    and populate OUT with them.  */
 104
 105 void
 106 make_checkers (auto_delete_vec <state_machine> &out, logger *logger)
 107 {
 108   out.safe_push (make_malloc_state_machine (logger));
 109   out.safe_push (make_fileptr_state_machine (logger));
 110   /* The "taint" checker must be explicitly enabled (as it currently
 111      leads to state explosions that stop the other checkers working).  */
 112   if (flag_analyzer_checker)
 113     out.safe_push (make_taint_state_machine (logger));
 114   out.safe_push (make_sensitive_state_machine (logger));
 115   out.safe_push (make_signal_state_machine (logger));
 116
 117   /* We only attempt to run the pattern tests if it might have been manually
 118      enabled (for DejaGnu purposes).  */
 119   if (flag_analyzer_checker)
 120     out.safe_push (make_pattern_test_state_machine (logger));
 121
 122   if (flag_analyzer_checker)
 123     {
 124       unsigned read_index, write_index;
 125       state_machine **sm;
 126
 127       /* TODO: this leaks the machines
 128          Would be nice to log the things that were removed.  */
 129       VEC_ORDERED_REMOVE_IF (out, read_index, write_index, sm,
 130                              0 != strcmp (flag_analyzer_checker,
 131                                           (*sm)->get_name ()));
 132     }
 133 }
 134
 135 } // namespace ana
 136
 137 #endif /* #if ENABLE_ANALYZER */