void cfg_dominatorst::construct_cfg(
const goto_programt &program,
goto_programt::const_targett PC)
{
nodet &node=node_map[PC];
node.PC=PC;
program.get_successors(PC, node.successors);
// now do backward edges
for(goto_programt::const_targetst::const_iterator
s_it=node.successors.begin();
s_it!=node.successors.end();
s_it++)
{
node_map[*s_it].predecessors.push_back(node.PC);
}
}
void remove_unreachable(goto_programt &goto_program)
{
std::set<goto_programt::targett> reachable;
std::stack<goto_programt::targett> working;
working.push(goto_program.instructions.begin());
while(!working.empty())
{
goto_programt::targett t=working.top();
working.pop();
if(reachable.find(t)==reachable.end() &&
t!=goto_program.instructions.end())
{
reachable.insert(t);
goto_programt::targetst successors;
goto_program.get_successors(t, successors);
for(goto_programt::targetst::const_iterator
s_it=successors.begin();
s_it!=successors.end();
s_it++)
working.push(*s_it);
}
}
// make all unreachable code a skip
// unless it's an 'end_function'
Forall_goto_program_instructions(it, goto_program)
{
if(reachable.find(it)==reachable.end() &&
!it->is_end_function())
it->make_skip();
}
}