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 
19 
20 #include "function.h"
21 
22 void branch(
23  goto_modelt &goto_model,
24  const irep_idt &id)
25 {
26  for(auto &gf_entry : goto_model.goto_functions.function_map)
27  {
28  // don't instrument our internal functions
29  if(has_prefix(id2string(gf_entry.first), CPROVER_PREFIX))
30  continue;
31 
32  // don't instrument the function to be called,
33  // or otherwise this will be recursive
34  if(gf_entry.first == id)
35  continue;
36 
37  // patch in a call to `id' at the branch points
38  goto_programt &body = gf_entry.second.body;
39 
41  {
42  // if C goto T is transformed into:
43  //
44  // if !C goto T' i_it
45  // id("taken"); t1
46  // goto T t2
47  // T': id("not-taken"); t3
48  // ...
49 
50  if(i_it->is_goto() && !i_it->get_condition().is_constant())
51  {
52  // negate condition
53  i_it->set_condition(boolean_negate(i_it->get_condition()));
54 
56  i_it,
58  function_to_call(goto_model.symbol_table, id, "taken")));
59 
61  t1, goto_programt::make_goto(i_it->get_target(), true_exprt()));
62 
64  t2,
66  function_to_call(goto_model.symbol_table, id, "not-taken")));
67  i_it->targets.clear();
68  i_it->targets.push_back(t3);
69  }
70  }
71  }
72 }
void branch(goto_modelt &goto_model, const irep_idt &id)
Definition: branch.cpp:22
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:71
instructionst::iterator targett
Definition: goto_program.h:646
targett insert_after(const_targett target)
Insertion after the instruction pointed-to by the given instruction iterator target.
Definition: goto_program.h:722
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())
The Boolean constant true.
Definition: std_expr.h:2802
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:125
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:25
Function Entering and Exiting.
Symbol Table + CFG.
#define Forall_goto_program_instructions(it, program)
const std::string & id2string(const irep_idt &d)
Definition: irep.h:49