def wrap_terminal(self, o):
v = self._expr2variable.get(o)
if v is None:
if o in self._duplications:
v = Variable(o)
self._expr2variable[o] = v
else:
v = o
return v
def reconstruct_variable(self, o):
# Check variable cache to reuse previously transformed variable if possible
e, l = o.operands()
v = self._variable_cache.get(l)
if v is not None:
return v
# Visit the expression our variable represents
e2 = self.visit(e)
# Always reconstruct Variable (with same label)
v = Variable(e2, l)
self._variable_cache[l] = v
return v
def expr(self, o, *ops):
v = self._expr2variable.get(o)
if v is None:
oo = o
# reconstruct if necessary
if not ops == o.operands():
o = o._uflclass(*ops)
if (oo in self._duplications) or (o in self._duplications):
v = Variable(o)
self._expr2variable[o] = v
self._expr2variable[oo] = v
else:
v = o
return v
def variable(self, o):
e, l = o.operands()
v = self._expr2variable.get(e)
if v is None:
e2 = self.visit(e)
# Unwrap expression from the newly created Variable wrapper
# unless the original expression was a Variable, in which
# case we possibly need to keep the label for correctness.
if (not isinstance(e, Variable)) and isinstance(e2, Variable):
e2 = e2._expression
v = self._expr2variable.get(e2)
if v is None:
v = Variable(e2, l)
self._expr2variable[e] = v
self._expr2variable[e2] = v
return v
def reuse_variable(self, o):
# Check variable cache to reuse previously transformed variable if possible
e, l = o.operands()
v = self._variable_cache.get(l)
if v is not None:
return v
# Visit the expression our variable represents
e2 = self.visit(e)
# If the expression is the same, reuse Variable object
if e == e2:
v = o
else:
# Recreate Variable (with same label)
v = Variable(e2, l)
# Cache variable
self._variable_cache[l] = v
return v