Commit 7ac3c5e7 authored by Alexandre Duret-Lutz's avatar Alexandre Duret-Lutz
Browse files

Remove prune_scc(), prune_acc(), and related fonctions.

* src/tgba/tgbareduc.cc, src/tgba/tgbareduc.hh (prune_scc,
prune_acc, remove_component, compute_scc, remove_acc,
is_not_accepting, delete_scc, is_terminal, remove_scc,
display_scc): Remove anything related to the simplification of
SCCs.
parent 7ea51cc6
2009-11-18 Alexandre Duret-Lutz <adl@lrde.epita.fr>
Remove prune_scc(), prune_acc(), and related fonctions.
* src/tgba/tgbareduc.cc, src/tgba/tgbareduc.hh (prune_scc,
prune_acc, remove_component, compute_scc, remove_acc,
is_not_accepting, delete_scc, is_terminal, remove_scc,
display_scc): Remove anything related to the simplification of
SCCs.
2009-11-18 Alexandre Duret-Lutz <adl@lrde.epita.fr>
Replace prune_scc() by scc_filter().
......
......@@ -29,19 +29,15 @@ namespace spot
typedef std::pair<const spot::state*, tgba_succ_iterator*> pair_state_iter;
}
tgba_reduc::tgba_reduc(const tgba* a,
const numbered_state_heap_factory* nshf)
tgba_reduc::tgba_reduc(const tgba* a)
: tgba_explicit_string(a->get_dict()),
tgba_reachable_iterator_breadth_first(a),
h_(nshf->build())
tgba_reachable_iterator_breadth_first(a)
{
dict_->register_all_variables_of(a, this);
run();
all_acceptance_conditions_ = a->all_acceptance_conditions();
all_acceptance_conditions_computed_ = true;
seen_ = 0;
scc_computed_ = false;
}
tgba_reduc::~tgba_reduc()
......@@ -52,8 +48,6 @@ namespace spot
{
delete i->second;
}
delete h_;
}
void
......@@ -130,17 +124,6 @@ namespace spot
this->merge_transitions();
}
void
tgba_reduc::prune_scc()
{
if (!scc_computed_)
this->compute_scc();
this->prune_acc();
this->delete_scc();
this->merge_transitions();
}
std::string
tgba_reduc::format_state(const spot::state* s) const
{
......@@ -148,15 +131,8 @@ namespace spot
const state_explicit* se = dynamic_cast<const state_explicit*>(s);
assert(se);
sn_map::const_iterator i = state_name_map_.find(se->get_state());
seen_map::const_iterator j = si_.find(s);
assert(i != state_name_map_.end());
if (j != si_.end()) // SCC have been computed
{
os << ", SCC " << j->second;
return i->second + std::string(os.str());
}
else
return i->second;
return i->second;
}
////////////////////////////////////////////
......@@ -443,381 +419,6 @@ namespace spot
// TO DO
}
/////////////////////////////////////////
/////////////////////////////////////////
// Compute SCC
// From gtec.cc
void
tgba_reduc::remove_component(const spot::state* from)
{
std::stack<tgba_succ_iterator*> to_remove;
numbered_state_heap::state_index_p spi = h_->index(from);
assert(spi.first);
assert(*spi.second != -1);
*spi.second = -1;
tgba_succ_iterator* i = this->succ_iter(from);
for (;;)
{
for (i->first(); !i->done(); i->next())
{
spot::state* s = i->current_state();
numbered_state_heap::state_index_p spi = h_->index(s);
if (!spi.first)
continue;
if (*spi.second != -1)
{
*spi.second = -1;
to_remove.push(this->succ_iter(spi.first));
}
}
delete i;
if (to_remove.empty())
break;
i = to_remove.top();
to_remove.pop();
}
}
// From gtec.cc
void
tgba_reduc::compute_scc()
{
std::stack<bdd> arc;
int num = 1;
std::stack<pair_state_iter> todo;
{
spot::state* init = this->get_init_state();
h_->insert(init, 1);
si_[init] = 1;
state_scc_.push(init);
root_.push(1);
arc.push(bddfalse);
tgba_succ_iterator* iter = this->succ_iter(init);
iter->first();
todo.push(pair_state_iter(init, iter));
}
while (!todo.empty())
{
assert(root_.size() == arc.size());
tgba_succ_iterator* succ = todo.top().second;
if (succ->done())
{
const spot::state* curr = todo.top().first;
todo.pop();
numbered_state_heap::state_index_p spi = h_->index(curr);
assert(spi.first);
assert(!root_.empty());
if (root_.top().index == *spi.second)
{
assert(!arc.empty());
arc.pop();
root_.pop();
remove_component(curr);
}
delete succ;
continue;
}
const spot::state* dest = succ->current_state();
bdd acc = succ->current_acceptance_conditions();
succ->next();
numbered_state_heap::state_index_p spi = h_->find(dest);
if (!spi.first)
{
h_->insert(dest, ++num);
si_[dest] = num;
state_scc_.push(dest);
root_.push(num);
arc.push(acc);
tgba_succ_iterator* iter = this->succ_iter(dest);
iter->first();
todo.push(pair_state_iter(dest, iter));
continue;
}
if (*spi.second == -1)
continue;
int threshold = *spi.second;
while (threshold < root_.top().index)
{
assert(!root_.empty());
assert(!arc.empty());
acc |= root_.top().condition;
acc |= arc.top();
root_.pop();
arc.pop();
si_[state_scc_.top()] = threshold;
state_scc_.pop();
}
root_.top().condition |= acc;
}
seen_map::iterator i;
for (i = si_.begin(); i != si_.end(); ++i)
{
state_scc_v_[i->second] = i->first;
}
scc_computed_ = true;
}
///////////////////////////////////////////////////////
///////////////////////////////////////////////////////
void
tgba_reduc::prune_acc()
{
if (!scc_computed_)
this->compute_scc();
Sgi::hash_map<int, const spot::state*>::iterator i;
for (i = state_scc_v_.begin(); i != state_scc_v_.end(); ++i)
{
if (is_not_accepting(i->second))
remove_acc(i->second);
}
}
void
tgba_reduc::remove_acc(const spot::state* s)
{
tgba_explicit::state* s1;
seen_map::iterator sm = si_.find(s);
sm = si_.find(s);
int n = sm->second;
for (sm == si_.begin(); sm != si_.end(); ++sm)
{
if (sm->second == n)
{
s1 = name_state_map_[tgba_explicit_string::format_state(s)];
s1 = const_cast<tgba_explicit::state*>(s1);
for (state::iterator i = s1->begin();
i != s1->end(); ++i)
(*i)->acceptance_conditions = bddfalse;
}
}
}
bool
tgba_reduc::is_not_accepting(const spot::state* s,
int n)
{
bool b = false;
// First call of is_terminal //
seen_map::const_iterator i;
if (n == -1)
{
acc_ = bddfalse;
b = true;
assert(seen_ == 0);
seen_ = new seen_map();
i = si_.find(s);
assert(i->first != 0);
n = i->second;
}
///////////////////////////////
seen_map::const_iterator sm = seen_->find(s);
if (sm == seen_->end())
{
// this state is visited for the first time.
seen_->insert(std::pair<const spot::state*, int>(s, 1));
i = si_.find(s);
assert(i->first != 0);
if (n != i->second)
return true;
}
else
// This state is already visited.
{
delete s;
s = 0;
return true;
}
spot::state* s2;
tgba_succ_iterator* j = this->succ_iter(s);
for (j->first(); !j->done(); j->next())
{
s2 = j->current_state();
i = si_.find(s2);
assert(i->first != 0);
if (n == i->second)
{
acc_ |= j->current_acceptance_conditions();
this->is_not_accepting(s2, n);
}
}
delete j;
// First call of is_terminal //
if (b)
{
for (seen_map::iterator i = seen_->begin();
i != seen_->end(); ++i)
{
s2 = const_cast<spot::state*>(i->first);
assert(s2 != 0);
delete dynamic_cast<tgba_explicit*>(s2);
}
seen_->clear();
delete seen_;
seen_ = 0;
return acc_ != this->all_acceptance_conditions();
}
///////////////////////////////
return true;
}
void
tgba_reduc::delete_scc()
{
bool change = true;
Sgi::hash_map<int, const spot::state*>::iterator i;
spot::state* s;
// we check if there is a terminal SCC we can be remove while
// they have been one removed, because a terminal SCC removed
// can generate a new terminal SCC
while (change)
{
change = false;
for (i = state_scc_v_.begin(); i != state_scc_v_.end(); ++i)
{
s = (i->second)->clone();
if (is_terminal(s))
{
change = true;
remove_scc(const_cast<spot::state*>(i->second));
state_scc_v_.erase(i);
break;
}
delete s;
}
}
}
bool
tgba_reduc::is_terminal(const spot::state* s, int n)
{
// a SCC is terminal if there are no transition
// leaving the SCC AND she doesn't contain all
// the acceptance condition.
// So we can remove it safely without change the
// automaton language.
bool b = false;
// First call of is_terminal //
seen_map::const_iterator i;
if (n == -1)
{
acc_ = bddfalse;
b = true;
assert(seen_ == 0);
seen_ = new seen_map();
i = si_.find(s);
assert(i->first != 0);
n = i->second;
}
///////////////////////////////
seen_map::const_iterator sm = seen_->find(s);
if (sm == seen_->end())
{
// this state is visited for the first time.
seen_->insert(std::pair<const spot::state*, int>(s, 1));
i = si_.find(s);
assert(i->first != 0);
if (n != i->second)
return false;
}
else
{
// This state is already visited.
delete s;
s = 0;
return true;
}
bool ret = true;
spot::state* s2;
tgba_succ_iterator* j = this->succ_iter(s);
for (j->first(); !j->done(); j->next())
{
s2 = j->current_state();
acc_ |= j->current_acceptance_conditions();
ret &= this->is_terminal(s2, n);
if (!ret)
break;
}
delete j;
// First call of is_terminal //
if (b)
{
for (seen_map::iterator i = seen_->begin();
i != seen_->end(); ++i)
{
s2 = const_cast<spot::state*>(i->first);
assert(s2 != 0);
delete dynamic_cast<tgba_explicit*>(s2);
}
seen_->clear();
delete seen_;
seen_ = 0;
if (acc_ == this->all_acceptance_conditions())
ret = false;
}
///////////////////////////////
return ret;
}
void
tgba_reduc::remove_scc(spot::state* s)
{
// To remove a scc, we remove all its states.
seen_map::iterator sm = si_.find(s);
sm = si_.find(s);
int n = sm->second;
for (sm == si_.begin(); sm != si_.end(); ++sm)
{
if (sm->second == n)
{
this->remove_state(const_cast<spot::state*>(sm->first));
sm->second = -1;
}
}
}
int
tgba_reduc::nb_set_acc_cond() const
{
......@@ -858,41 +459,4 @@ namespace spot
}
}
void
tgba_reduc::display_scc(std::ostream& os)
{
while (!root_.empty())
{
os << "index : " << root_.top().index << std::endl;
root_.pop();
}
seen_map::iterator i;
for (i = si_.begin(); i != si_.end(); ++i)
{
os << " [label=\""
<< this->format_state(i->first)
<< "\"]"
<< " scc : "
<< i->second
<< std::endl;
}
os << " Root of each SCC :"
<< std::endl;
Sgi::hash_map<int, const spot::state*>::iterator j;
for (j = state_scc_v_.begin(); j != state_scc_v_.end(); ++j)
{
os << " [label=\""
<< this->format_state(j->second)
<< "\"]"
<< std::endl;
state_scc_.pop();
}
}
}
......@@ -24,8 +24,6 @@
#include "tgbaexplicit.hh"
#include "tgbaalgos/reachiter.hh"
#include "tgbaalgos/gtec/explscc.hh"
#include "tgbaalgos/gtec/nsheap.hh"
#include <list>
#include <vector>
......@@ -54,9 +52,7 @@ namespace spot
public tgba_explicit_string, public tgba_reachable_iterator_breadth_first
{
public:
tgba_reduc(const tgba* a,
const numbered_state_heap_factory* nshf
= numbered_state_heap_hash_map_factory::instance());
tgba_reduc(const tgba* a);
~tgba_reduc();
......@@ -72,15 +68,6 @@ namespace spot
/// relation.
void delete_transitions(simulation_relation* rel);
/// Remove all state which not lead to an accepting cycle.
void prune_scc();
/// Remove some useless acceptance condition.
void prune_acc();
/// Compute the maximal SCC of the automata.
void compute_scc();
/// Add the SCC index to the display of the state \a state.
virtual std::string format_state(const spot::state* state) const;
......@@ -89,25 +76,11 @@ namespace spot
void display_scc(std::ostream& os);
protected:
bool scc_computed_;
scc_stack root_;
numbered_state_heap* h_;
std::stack<const spot::state*> state_scc_;
Sgi::hash_map<int, const spot::state*> state_scc_v_;
typedef Sgi::hash_map<const tgba_explicit::state*,
std::list<state*>*,
ptr_hash<tgba_explicit::state> > sp_map;
sp_map state_predecessor_map_;
// For reduction using scc.
typedef Sgi::hash_map<const spot::state*, int,
state_ptr_hash, state_ptr_equal> seen_map;
seen_map si_;
seen_map* seen_;
bdd acc_;
// Interface of tgba_reachable_iterator_breadth_first
void start();
void end();
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment