void dep_graph_domaint::data_dependencies(
goto_programt::const_targett from,
goto_programt::const_targett to,
dependence_grapht &dep_graph,
const namespacet &ns)
{
// data dependencies using def-use pairs
data_deps.clear();
// TODO use (future) reaching-definitions-dereferencing rw_set
value_setst &value_sets=
dep_graph.reaching_definitions().get_value_sets();
rw_range_set_value_sett rw_set(ns, value_sets);
goto_rw(to, rw_set);
forall_rw_range_set_r_objects(it, rw_set)
{
const range_domaint &r_ranges=rw_set.get_ranges(it);
const rd_range_domaint::ranges_at_loct &w_ranges=
dep_graph.reaching_definitions()[to].get(it->first);
for(const auto &w_range : w_ranges)
{
bool found=false;
for(const auto &wr : w_range.second)
for(const auto &r_range : r_ranges)
if(!found &&
may_be_def_use_pair(wr.first, wr.second,
r_range.first, r_range.second))
{
// found a def-use pair
data_deps.insert(w_range.first);
found=true;
}
}
dep_graph.reaching_definitions()[to].clear_cache(it->first);
}
// add edges to the graph
for(const auto &d_dep : data_deps)
{
// *it might be handled in a future call call to visit only,
// depending on the sequence of successors; make sure it exists
dep_graph.get_state(d_dep);
dep_graph.add_dep(dep_edget::kindt::DATA, d_dep, to);
}
}
void rd_range_domaint::transform(
locationt from,
locationt to,
ai_baset &ai,
const namespacet &ns)
{
reaching_definitions_analysist *rd=
dynamic_cast<reaching_definitions_analysist*>(&ai);
assert(rd!=0);
assert(bv_container);
// kill values
if(from->is_dead())
transform_dead(ns, from);
// kill thread-local values
else if(from->is_start_thread())
transform_start_thread(ns, *rd);
// do argument-to-parameter assignments
else if(from->is_function_call())
transform_function_call(ns, from, to, *rd);
// cleanup parameters
else if(from->is_end_function())
transform_end_function(ns, from, to, *rd);
// lhs assignements
else if(from->is_assign())
transform_assign(ns, from, from, *rd);
// initial (non-deterministic) value
else if(from->is_decl())
transform_assign(ns, from, from, *rd);
#if 0
// handle return values
if(to->is_function_call())
{
const code_function_callt &code=to_code_function_call(to->code);
if(code.lhs().is_not_nil())
{
rw_range_set_value_sett rw_set(ns, rd->get_value_sets());
goto_rw(to, rw_set);
const bool is_must_alias=rw_set.get_w_set().size()==1;
forall_rw_range_set_w_objects(it, rw_set)
{
const irep_idt &identifier=it->first;
// ignore symex::invalid_object
const symbolt *symbol_ptr;
if(ns.lookup(identifier, symbol_ptr))
continue;
assert(symbol_ptr!=0);
const range_domaint &ranges=rw_set.get_ranges(it);
if(is_must_alias &&
(!rd->get_is_threaded()(from) ||
(!symbol_ptr->is_shared() &&
!rd->get_is_dirty()(identifier))))
for(const auto &range : ranges)
kill(identifier, range.first, range.second);
}
}
}
