Massage the AST so that identical sub-formula share the same

reference-counted formula*.  One can't call constructors for AST
items anymore, everything need to be acquired through instance()
class methods.

* src/ltlast/formula.cc, src/ltlast/refformula.cc,
src/ltlast/refformula.hh: New files.
* src/ltlast/Makefile.am (libltlast_la_SOURCES): Add them.
* src/ltlast/atomic_prop.cc, src/ltlast/atomic_prop.hh,
src/ltlast/unop.cc, src/ltlast/unop.hh,
src/ltlast/binop.cc, src/ltlast/binop.hh: Make the constructor
and destructor protected.  Define a static function `instance()'
to get an instance with specific argument.  Use a map called
`instances' to store all known instances.  Inherit from
ref_formula.
* src/ltlast/constant.hh, src/ltlast/constant.cc: Protect
the constructor and destructor.  Provide the false_instance()
and true_instance() functions instead.
* src/formula.hh (ref, unref, ref_, unref_): New methods.
* src/ltlast/multop.cc, src/ltlast/multop.hh: Protect
the constructor, destructor, as well as the add() method.
Provides the instance(), and add() class methods instead.
Store children_ as a pointer.
* src/ltlenv/defaultenv.cc (require): Adjust to
call atomic_prop::instance.
* src/ltlparse/ltlparse.yy: Adjust to call instance() functions
instead of constructors.
* src/ltltest/Makefile.am (LDADD): Tweak library ordering.
* src/ltlvisit/clone.hh (clone_visitor): Inherit from visitor,
not const_visitor, and adjust all prototypes appropriately.
* src/ltlvisit/clone.cc (clone_visitor): Likewise.
Call ref() or instance() methods instead of copy constructors.
* src/ltlvisit/equals.cc: Simplify atomic_prop and constant
cases.
* src/ltlvisit/lunabbrev.hh, src/ltlvisit/lunabbrev.cc,
src/ltlvisit/tunabbrev.hh, src/ltlvisit/tunabbrev.cc,
src/ltlvisit/nenoform.hh, src/ltlvisit/nenoform.cc: Use instance()
methods instead of constructor.  Make these children of visitor, not
const_visitor.
* src/ltltest/readltl.c (main): Do not delete the formula.
This commit is contained in:
Alexandre Duret-Lutz 2003-05-15 13:39:39 +00:00
parent f1838ab8ef
commit 5f6d8b6234
29 changed files with 548 additions and 253 deletions

View file

@ -5,7 +5,7 @@ namespace spot
{
namespace ltl
{
atomic_prop::atomic_prop(const std::string& name, environment& env)
: name_(name), env_(&env)
{
@ -15,29 +15,45 @@ namespace spot
{
}
void
void
atomic_prop::accept(visitor& v)
{
v.visit(this);
}
void
atomic_prop::accept(const_visitor& v) const
{
v.visit(this);
}
}
const std::string&
atomic_prop::name() const
{
return name_;
}
environment&
environment&
atomic_prop::env() const
{
return *env_;
}
atomic_prop::map atomic_prop::instances;
atomic_prop*
atomic_prop::instance(const std::string& name, environment& env)
{
pair p(name, &env);
map::iterator i = instances.find(p);
if (i != instances.end())
{
return static_cast<atomic_prop*>(i->second->ref());
}
atomic_prop* ap = new atomic_prop(name, env);
instances[p] = ap;
return static_cast<atomic_prop*>(ap->ref());
}
}
}