cprover
symex_bmc_incremental_one_loop.cpp
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1 /*******************************************************************\
2 
3 Module: Incremental Bounded Model Checking for ANSI-C
4 
5 Author: Peter Schrammel, Daniel Kroening, kroening@kroening.com
6 
7 \*******************************************************************/
8 
9 #include <limits>
10 
11 #include <util/source_location.h>
12 #include <util/xml.h>
13 
15 
17  message_handlert &message_handler,
18  const symbol_tablet &outer_symbol_table,
19  symex_target_equationt &target,
20  const optionst &options,
21  path_storaget &path_storage,
22  guard_managert &guard_manager)
23  : symex_bmct(
24  message_handler,
25  outer_symbol_table,
26  target,
27  options,
28  path_storage,
29  guard_manager),
30  incr_loop_id(options.get_option("incremental-loop")),
31  incr_max_unwind(
32  options.is_set("unwind-max") ? options.get_signed_int_option("unwind-max")
33  : std::numeric_limits<unsigned>::max()),
34  incr_min_unwind(
35  options.is_set("unwind-min") ? options.get_signed_int_option("unwind-min")
36  : 0)
37 {
39  incr_min_unwind >= 1 &&
40  options.get_bool_option("ignore-properties-before-unwind-min");
41 }
42 
44  const symex_targett::sourcet &source,
45  const call_stackt &context,
46  unsigned unwind)
47 {
48  const irep_idt id = goto_programt::loop_id(source.function_id, *source.pc);
49 
50  tvt abort_unwind_decision;
51  unsigned this_loop_limit = std::numeric_limits<unsigned>::max();
52 
53  // use the incremental limits if it is the specified incremental loop
54  if(id == incr_loop_id)
55  {
56  this_loop_limit = incr_max_unwind;
57  if(unwind + 1 >= incr_min_unwind)
58  ignore_assertions = false;
59  abort_unwind_decision = tvt(unwind >= this_loop_limit);
60  }
61  else
62  {
63  for(auto handler : loop_unwind_handlers)
64  {
65  abort_unwind_decision =
66  handler(context, source.pc->loop_number, unwind, this_loop_limit);
67  if(abort_unwind_decision.is_known())
68  break;
69  }
70 
71  // If no handler gave an opinion, use standard command-line --unwindset
72  // / --unwind options to decide:
73  if(abort_unwind_decision.is_unknown())
74  {
75  auto limit = unwindset.get_limit(id, source.thread_nr);
76 
77  if(!limit.has_value())
78  abort_unwind_decision = tvt(false);
79  else
80  abort_unwind_decision = tvt(unwind >= *limit);
81  }
82  }
83 
84  INVARIANT(
85  abort_unwind_decision.is_known(), "unwind decision should be taken by now");
86  bool abort = abort_unwind_decision.is_true();
87 
88  log.statistics() << (abort ? "Not unwinding" : "Unwinding") << " loop " << id
89  << " iteration " << unwind;
90 
91  if(this_loop_limit != std::numeric_limits<unsigned>::max())
92  log.statistics() << " (" << this_loop_limit << " max)";
93 
94  log.statistics() << " " << source.pc->source_location << " thread "
95  << source.thread_nr << log.eom;
96 
97  return abort;
98 }
99 
104  const irep_idt &loop_id,
105  unsigned unwind)
106 {
107  if(unwind < incr_min_unwind)
108  return false;
109 
110  // loop specified by incremental-loop
111  return (loop_id == incr_loop_id);
112 }
113 
115  const get_goto_functiont &get_goto_function,
116  symbol_tablet &new_symbol_table)
117 {
119 
120  symex_with_state(*state, get_goto_function, new_symbol_table);
121 
122  return should_pause_symex;
123 }
124 
126  const get_goto_functiont &get_goto_function)
127 {
128  should_pause_symex = false;
129 
130  symex_with_state(*state, get_goto_function, state->symbol_table);
131 
132  return should_pause_symex;
133 }
goto_symext::symex_with_state
virtual void symex_with_state(statet &state, const get_goto_functiont &get_goto_functions, symbol_tablet &new_symbol_table)
Symbolically execute the entire program starting from entry point.
Definition: symex_main.cpp:322
dstringt
dstringt has one field, an unsigned integer no which is an index into a static table of strings.
Definition: dstring.h:37
symbol_tablet
The symbol table.
Definition: symbol_table.h:20
symex_bmct::loop_unwind_handlers
std::vector< loop_unwind_handlert > loop_unwind_handlers
Callbacks that may provide an unwind/do-not-unwind decision for a loop.
Definition: symex_bmc.h:89
symex_bmct::unwindset
unwindsett unwindset
Definition: symex_bmc.h:85
optionst
Definition: options.h:23
symex_bmc_incremental_one_loop.h
symex_targett::sourcet::pc
goto_programt::const_targett pc
Definition: symex_target.h:43
path_storaget
Storage for symbolic execution paths to be resumed later.
Definition: path_storage.h:38
goto_symext::ignore_assertions
bool ignore_assertions
If this flag is set to true then assertions will be temporarily ignored by the symbolic executions.
Definition: goto_symex.h:169
symex_bmc_incremental_one_loopt::check_break
bool check_break(const irep_idt &loop_id, unsigned unwind) override
Defines condition for interrupting symbolic execution for incremental BMC.
Definition: symex_bmc_incremental_one_loop.cpp:103
symex_targett::sourcet::thread_nr
unsigned thread_nr
Definition: symex_target.h:39
tvt::is_unknown
bool is_unknown() const
Definition: threeval.h:27
messaget::eom
static eomt eom
Definition: message.h:283
call_stackt
Definition: call_stack.h:15
xml.h
goto_symext::initialize_entry_point_state
std::unique_ptr< statet > initialize_entry_point_state(const get_goto_functiont &get_goto_function)
Initialize the symbolic execution and the given state with the beginning of the entry point function.
Definition: symex_main.cpp:401
tvt::is_known
bool is_known() const
Definition: threeval.h:28
unwindsett::get_limit
optionalt< unsigned > get_limit(const irep_idt &loop, unsigned thread_id) const
Definition: unwindset.cpp:73
goto_programt::loop_id
static irep_idt loop_id(const irep_idt &function_id, const instructiont &instruction)
Human-readable loop name.
Definition: goto_program.h:755
goto_symext::log
messaget log
The messaget to write log messages to.
Definition: goto_symex.h:276
guard_expr_managert
This is unused by this implementation of guards, but can be used by other implementations of the same...
Definition: guard_expr.h:23
symex_bmc_incremental_one_loopt::state
std::unique_ptr< goto_symext::statet > state
Definition: symex_bmc_incremental_one_loop.h:38
source_location.h
message_handlert
Definition: message.h:27
symex_bmc_incremental_one_loopt::incr_max_unwind
const unsigned incr_max_unwind
Definition: symex_bmc_incremental_one_loop.h:35
tvt
Definition: threeval.h:20
symex_target_equationt
Inheriting the interface of symex_targett this class represents the SSA form of the input program as ...
Definition: symex_target_equation.h:39
symex_bmc_incremental_one_loopt::should_stop_unwind
bool should_stop_unwind(const symex_targett::sourcet &source, const call_stackt &context, unsigned unwind) override
Determine whether to unwind a loop.
Definition: symex_bmc_incremental_one_loop.cpp:43
optionst::get_bool_option
bool get_bool_option(const std::string &option) const
Definition: options.cpp:44
goto_symext::get_goto_function
static get_goto_functiont get_goto_function(abstract_goto_modelt &goto_model)
Return a function to get/load a goto function from the given goto model Create a default delegate to ...
Definition: symex_main.cpp:491
symex_bmc_incremental_one_loopt::incr_min_unwind
const unsigned incr_min_unwind
Definition: symex_bmc_incremental_one_loop.h:36
symex_bmc_incremental_one_loopt::incr_loop_id
const irep_idt incr_loop_id
Definition: symex_bmc_incremental_one_loop.h:34
symex_bmc_incremental_one_loopt::resume
bool resume(const get_goto_functiont &get_goto_function)
Return true if symex can be resumed.
Definition: symex_bmc_incremental_one_loop.cpp:125
goto_symext::get_goto_functiont
std::function< const goto_functionst::goto_functiont &(const irep_idt &)> get_goto_functiont
The type of delegate functions that retrieve a goto_functiont for a particular function identifier.
Definition: goto_symex.h:95
symex_bmct
Definition: symex_bmc.h:26
symex_targett::sourcet
Identifies source in the context of symbolic execution.
Definition: symex_target.h:38
symex_bmc_incremental_one_loopt::symex_bmc_incremental_one_loopt
symex_bmc_incremental_one_loopt(message_handlert &, const symbol_tablet &outer_symbol_table, symex_target_equationt &, const optionst &, path_storaget &, guard_managert &)
Definition: symex_bmc_incremental_one_loop.cpp:16
symex_bmc_incremental_one_loopt::from_entry_point_of
bool from_entry_point_of(const get_goto_functiont &get_goto_function, symbol_tablet &new_symbol_table)
Return true if symex can be resumed.
Definition: symex_bmc_incremental_one_loop.cpp:114
symex_targett::sourcet::function_id
irep_idt function_id
Definition: symex_target.h:40
validation_modet::INVARIANT
@ INVARIANT
tvt::is_true
bool is_true() const
Definition: threeval.h:25
messaget::statistics
mstreamt & statistics() const
Definition: message.h:405
goto_symext::should_pause_symex
bool should_pause_symex
Set when states are pushed onto the workqueue If this flag is set at the end of a symbolic execution ...
Definition: goto_symex.h:165