cprover
branch.cpp
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1 /*******************************************************************\
2 
3 Module: Branch Instrumentation
4 
5 Author: Daniel Kroening, kroening@kroening.com
6 
7 \*******************************************************************/
8 
11 
12 #include "branch.h"
13 
14 #include <util/cprover_prefix.h>
15 #include <util/expr_util.h>
16 #include <util/prefix.h>
17 
18 #include "function.h"
19 
20 void branch(
21  goto_modelt &goto_model,
22  const irep_idt &id)
23 {
24  for(auto &gf_entry : goto_model.goto_functions.function_map)
25  {
26  // don't instrument our internal functions
27  if(has_prefix(id2string(gf_entry.first), CPROVER_PREFIX))
28  continue;
29 
30  // don't instrument the function to be called,
31  // or otherwise this will be recursive
32  if(gf_entry.first == id)
33  continue;
34 
35  // patch in a call to `id' at the branch points
36  goto_programt &body = gf_entry.second.body;
37 
39  {
40  // if C goto T is transformed into:
41  //
42  // if !C goto T' i_it
43  // id("taken"); t1
44  // goto T t2
45  // T': id("not-taken"); t3
46  // ...
47 
48  if(i_it->is_goto() && !i_it->get_condition().is_constant())
49  {
50  // negate condition
51  i_it->set_condition(boolean_negate(i_it->get_condition()));
52 
54  i_it,
56  function_to_call(goto_model.symbol_table, id, "taken")));
57 
59  t1, goto_programt::make_goto(i_it->get_target(), true_exprt()));
60 
62  t2,
64  function_to_call(goto_model.symbol_table, id, "not-taken")));
65  i_it->targets.clear();
66  i_it->targets.push_back(t3);
67  }
68  }
69  }
70 }
void branch(goto_modelt &goto_model, const irep_idt &id)
Definition: branch.cpp:20
Branch Instrumentation.
dstringt has one field, an unsigned integer no which is an index into a static table of strings.
Definition: dstring.h:37
function_mapt function_map
symbol_tablet symbol_table
Symbol table.
Definition: goto_model.h:30
goto_functionst goto_functions
GOTO functions.
Definition: goto_model.h:33
A generic container class for the GOTO intermediate representation of one function.
Definition: goto_program.h:74
instructionst::iterator targett
Definition: goto_program.h:550
targett insert_after(const_targett target)
Insertion after the instruction pointed-to by the given instruction iterator target.
Definition: goto_program.h:626
static instructiont make_function_call(const code_function_callt &_code, const source_locationt &l=source_locationt::nil())
Create a function call instruction.
static instructiont make_goto(targett _target, const source_locationt &l=source_locationt::nil())
Definition: goto_program.h:969
The Boolean constant true.
Definition: std_expr.h:2717
bool has_prefix(const std::string &s, const std::string &prefix)
Definition: converter.cpp:13
#define CPROVER_PREFIX
exprt boolean_negate(const exprt &src)
negate a Boolean expression, possibly removing a not_exprt, and swapping false and true
Definition: expr_util.cpp:128
Deprecated expression utility functions.
code_function_callt function_to_call(symbol_tablet &symbol_table, const irep_idt &id, const irep_idt &argument)
Definition: function.cpp:22
Function Entering and Exiting.
#define Forall_goto_program_instructions(it, program)
const std::string & id2string(const irep_idt &d)
Definition: irep.h:49