def toConstraintTerm(self, maxTimeStamp=None):
if self.name == SymbolTable.MAXTIME:
assert maxTimeStamp is not None
yterm = Terms.get_by_name(SymbolTable.MAXTIME)
assert yterm is not None
return Terms.eq(yterm, YicesSignature.integer(maxTimeStamp))
def constrainVariable(maxValue):
if maxValue is not None:
ymax = None
if maxValue == SymbolTable.MAXTIME:
ymax = Terms.get_by_name(SymbolTable.MAXTIME)
else:
ymax = YicesSignature.integer(maxValue)
yterms = [ Terms.arith_leq_atom(YicesSignature.integer(0), self.yices_term),
Terms.arith_leq_atom(self.yices_term, ymax) ]
return Terms.yand(yterms)
return Terms.arith_leq_atom(YicesSignature.integer(0), self.yices_term)
if self.vartype.name == SymbolTable.TIME:
return constrainVariable(SymbolTable.MAXTIME)
if self.vartype.name == SymbolTable.STAGE:
return constrainVariable(Configuration.stage_count - 1)
if self.vartype.name == SymbolTable.NAT:
if self.yices_type == SymbolTable.BINDEX:
return constrainVariable(Configuration.bot_count - 1)
if self.yices_type == SymbolTable.OBINDEX:
return constrainVariable(Configuration.obs_count - 1)
if self.yices_type == SymbolTable.XAXIS:
return constrainVariable(Configuration.grid_dimension[0] - 1)
if self.yices_type == SymbolTable.YAXIS:
return constrainVariable(Configuration.grid_dimension[1] - 1)
return None
def constrainVariable(maxValue):
if maxValue is not None:
ymax = None
if maxValue == SymbolTable.MAXTIME:
ymax = Terms.get_by_name(SymbolTable.MAXTIME)
else:
ymax = YicesSignature.integer(maxValue)
yterms = [ Terms.arith_leq_atom(YicesSignature.integer(0), self.yices_term),
Terms.arith_leq_atom(self.yices_term, ymax) ]
return Terms.yand(yterms)
return Terms.arith_leq_atom(YicesSignature.integer(0), self.yices_term)
def declare_variable(var, bound_variables):
""" constructs the yices term associated with the logical variable.
In the case that bound_variables is not None, we are parsing an invariant,
so that any NEW variables that we see are taken to be bound by the implicit universal
quantifiers.
"""
varname = var.name
vartype = var.vartype
# check if it is bound and has already been seen
if bound_variables is not None and varname in bound_variables:
yvar = bound_variables[varname].yices_term
var.bound = True
return yvar
# check if it has already been seen
yvar = Terms.get_by_name(varname)
if yvar is not None:
#now we need to see if it is free or bound
tag = Terms.constructor(yvar)
if tag == Constructor.VARIABLE:
var.bound = True
bound_variables[varname] = var
return yvar
type_term = vartype.yices_term
type_name = vartype.name
var_term = None
if bound_variables is not None:
# we need to make a yices variable not an uninterpreted term
var_term = Terms.new_variable(type_term, varname)
if var_term is None:
sys.stderr.write(
f'declare_variable: Term.new_variable failed {Yices.error_string()}\n'
)
return None
bound_variables[varname] = var
var.bound = True
else:
var_term = Terms.new_uninterpreted_term(type_term, varname)
if var_term is None:
sys.stderr.write(
f'declare_variable: Term.new_uninterpreted_term failed {Yices.error_string()}\n'
)
return None
YicesSignature.types_to_variables[type_name].add(var)
return var_term