def visit_stm_wrapper(self, obj: StmWrapper):
stm = obj.to_stm()
stm.accept(self)
class IRBuilder(Visitor):
def __init__(self, table: Table):
Visitor.__init__(self)
self.table = table
self.main_subtree = None
self.trees = dict()
self.current_frame: IFrame = None
self.type_stack_visitor = TypeStackVisitor(table)
def parse(self, program: Program):
program.accept(self)
def get_parse_result(self):
return self.trees
def visit(self, obj: Visitable):
if isinstance(obj, BinaryExpr):
self.visit_binary_expr(obj)
elif isinstance(obj, Id):
self.visit_id(obj)
elif isinstance(obj, ClassDecl):
self.visit_class_decl(obj)
elif isinstance(obj, MainClass):
self.visit_main_class(obj)
elif isinstance(obj, MethodDecl):
self.visit_method_decl(obj)
elif isinstance(obj, Program):
self.visit_program(obj)
elif isinstance(obj, ValueExpr):
self.visit_value_expr(obj)
elif isinstance(obj, AssignStatement):
self.visit_assign_statement(obj)
elif isinstance(obj, IfStatement):
self.visit_if_statement(obj)
elif isinstance(obj, NotExpr):
self.visit_not_expr(obj)
elif isinstance(obj, CallMethodExpr):
self.visit_call_method_expr(obj)
elif isinstance(obj, NewIntArrExpr):
self.visit_new_int_array_expr(obj)
elif isinstance(obj, NewObjectExpr):
self.visit_new_object_expr(obj)
elif isinstance(obj, RandomAccessAssignStatement):
self.visit_random_access_assign_statement(obj)
elif isinstance(obj, LengthExpr):
self.visit_length_expr(obj)
elif isinstance(obj, PrintLineStatement):
self.visit_print_line_statement(obj)
elif isinstance(obj, WhileStatement):
self.visit_while_statement(obj)
elif isinstance(obj, Statements):
self.visit_statements(obj)
elif isinstance(obj, RandomAccessExpr):
self.visit_random_access_expr(obj)
elif isinstance(obj, ThisExpr):
self.visit_this_expr(obj)
elif isinstance(obj, ReturnStatement):
self.visit_return_statement(obj)
def visit_program(self, obj: Program):
obj.main.accept(self)
for class_decl in obj.class_decl_list:
class_decl.accept(self)
def visit_main_class(self, obj: MainClass):
for statement in obj.statement_list:
statement.accept(self)
assert self.main_subtree is not None
self.trees[obj.id.name + '@MAIN'] = self.main_subtree
self.main_subtree = None
def visit_class_decl(self, obj: ClassDecl):
switcher = TypeScopeSwitcher(
self.table.get_class(obj.id.name).type_info,
None,
self.table,
obj.position
)
for method_decl in obj.method_decl_list:
method_decl.accept(self)
switcher.destroy()
def visit_method_decl(self, obj: MethodDecl):
method_info = self.table.get_method(obj.id.name, obj.position)
switcher = MethodScopeSwitcher(
method_info,
None,
self.table,
obj.position
)
self.current_frame = method_info.get_frame()
stm = None
if len(obj.statement_list) > 0:
statements = []
for statement in obj.statement_list:
statement.accept(self)
statements.append(self.main_subtree.to_stm())
assert len(statements) > 0
if len(statements) == 1:
self.main_subtree = StmWrapper(statements[0])
else:
seq = Seq(statements[0], statements[1], obj.position)
for i in range(2, len(statements), 1):
seq = Seq(seq, statements[i], obj.position)
self.main_subtree = StmWrapper(seq)
stm = StmList(self.main_subtree.to_stm(), None, obj.position)
obj.return_statement.accept(self)
if stm is not None:
stm = StmList(stm, self.main_subtree.to_stm(), obj.position)
else:
stm = self.main_subtree.to_stm()
name = method_info.get_full_name()
self.trees[name] = StmWrapper(stm)
switcher.destroy()
def visit_binary_expr(self, obj: BinaryExpr):
obj.left.accept(self)
left = self.main_subtree.to_exp()
self.type_stack_visitor.pop_type_from_stack()
obj.right.accept(self)
right = self.main_subtree.to_exp()
self.type_stack_visitor.pop_type_from_stack()
if obj.binary_enum == BinaryEnum.MINUS:
result = Binop(BinopEnum.MINUS, left, right, obj.position)
elif obj.binary_enum == BinaryEnum.MULT:
result = Binop(BinopEnum.MUL, left, right, obj.position)
elif obj.binary_enum == BinaryEnum.PLUS:
result = Binop(BinopEnum.PLUS, left, right, obj.position)
elif obj.binary_enum == BinaryEnum.MOD:
result = Binop(BinopEnum.MOD, left, right, obj.position)
elif obj.binary_enum == BinaryEnum.LESS:
true_label = Label.get_next_enumerated_label()
false_label = Label.get_next_enumerated_label()
return_label = Label.get_next_enumerated_label()
condition = JumpC(JumpTypeEnum.LT, left, right, true_label, obj.position)
exp_value = Temp('exp_value', None, None, obj.position)
true_branch = Seq(
Seq(
LabelStm(
true_label,
obj.position
),
Move(
exp_value,
Const(
1,
obj.position
),
obj.position
),
obj.position
),
Jump(
return_label,
obj.position
),
obj.position
)
false_branch = Seq(
Seq(
LabelStm(
false_label,
obj.position
),
Move(
Temp(None, None, exp_value),
Const(
0,
obj.position
),
obj.position
),
obj.position
),
Jump(
return_label,
obj.position
),
obj.position
)
result = Eseq(
Seq(
Seq(
Seq(
condition,
false_branch,
obj.position
),
true_branch,
obj.position
),
LabelStm(
return_label,
obj.position
),
obj.position
),
Mem(
Temp(None, None, exp_value),
obj.position
),
obj.position
)
elif obj.binary_enum == BinaryEnum.AND:
true_label = Label.get_next_enumerated_label()
false_label = Label.get_next_enumerated_label()
return_label = Label.get_next_enumerated_label()
exp_value = Temp('exp_value', None, None, obj.position)
condition = JumpC(JumpTypeEnum.NEQ, left, Const(1, obj.position), false_label, obj.position)
true_branch = Seq(
JumpC(JumpTypeEnum.NEQ, right, Const(1, obj.position), false_label, obj.position),
Seq(
Move(exp_value, Const(1, obj.position), obj.position),
Jump(return_label, obj.position),
obj.position
),
obj.position
)
false_branch = Seq(
LabelStm(false_label, obj.position),
Seq(
Move(Temp(None, None, exp_value), Const(0, obj.position), obj.position),
Jump(return_label, obj.position),
obj.position
),
obj.position
)
result = Eseq(
Seq(
Seq(
Seq(
condition,
true_branch,
obj.position
),
false_branch,
obj.position
),
LabelStm(return_label, obj.position),
obj.position
),
Mem(Temp(None, None, exp_value), obj.position),
obj.position
)
elif obj.binary_enum == BinaryEnum.OR:
true_label = Label.get_next_enumerated_label()
false_label = Label.get_next_enumerated_label()
return_label = Label.get_next_enumerated_label()
exp_value = Temp('exp_value', None, None, obj.position)
condition = JumpC(JumpTypeEnum.EQ, left, Const(1, obj.position), true_label, obj.position)
true_branch = Seq(
JumpC(JumpTypeEnum.NEQ, right, Const(1, obj.position), false_label, obj.position),
Seq(
LabelStm(true_label, obj.position),
Seq(
Move(exp_value, Const(1, obj.position), obj.position),
Jump(return_label, obj.position),
obj.position
),
obj.position
),
obj.position
)
false_branch = Seq(
LabelStm(false_label, obj.position),
Seq(
Move(Temp(None, None, exp_value), Const(0, obj.position), obj.position),
Jump(return_label, obj.position),
obj.position
),
obj.position
)
result = Eseq(
Seq(
Seq(
Seq(
condition,
true_branch,
obj.position
),
false_branch,
obj.position
),
LabelStm(return_label, obj.position),
obj.position
),
Mem(Temp(None, None, exp_value), obj.position),
obj.position
)
else:
raise Exception('Hello there! - General Kenobi!')
self.main_subtree = ExpWrapper(result)
self.type_stack_visitor.visit(obj)
def visit_id(self, obj: Id):
var_access: IAccess = self.current_frame.find_local_or_formal(obj.name)
if var_access is not None:
var_exp = var_access.get_exp(
Temp(
fp_name,
None, None,
obj.position
),
obj.position
)
else:
assert self.table.get_scoped_class() is not None
var_exp = self.table.get_scoped_class().class_struct.get_field_from(
obj.name,
self.current_frame.find_local_or_formal(THIS_NAME).get_exp(
Temp(
fp_name,
None, None,
obj.position
),
obj.position
),
obj.position
)
self.type_stack_visitor.visit(obj)
self.main_subtree = ExpWrapper(var_exp)
def visit_value_expr(self, obj: ValueExpr):
self.main_subtree = ExpWrapper(Const(obj.value, obj.position))
self.type_stack_visitor.visit(obj)
def visit_assign_statement(self, obj: AssignStatement):
obj.right.accept(self)
access = self.current_frame.find_local_or_formal(obj.left.name)
if access is not None:
base_address = access.get_exp(
Temp(fp_name, None, None, obj.position),
obj.position
)
else:
base_address = self.table.get_scoped_class().class_struct.get_field_from(
obj.left.name,
self.current_frame.find_local_or_formal(
THIS_NAME,
).get_exp(Temp(fp_name, None, None, obj.position), obj.position),
obj.position
)
self.main_subtree = StmWrapper(Move(base_address, self.main_subtree.to_exp(), obj.position))
def visit_not_expr(self, obj: NotExpr):
obj.right.accept(self)
self.type_stack_visitor.pop_type_from_stack()
self.main_subtree = ExpWrapper(UnaryOp(UnaryOpEnum.NOT, self.main_subtree.to_exp(), obj.position))
self.type_stack_visitor.visit(obj)
def visit_call_method_expr(self, obj: CallMethodExpr):
obj.expr.accept(self)
base_address = Temp(None, 0, None, obj.position)
base_exp = Eseq(
Move(
base_address,
self.main_subtree.to_exp(),
obj.position
),
Mem(
Temp(
None, None, base_address, obj.position
),
obj.position
)
)
info: TypeInfo = self.type_stack_visitor.get_type_from_stack()
assert info is not None
assert info.type_enum == TypeEnum.USER_CLASS
type_switcher = TypeScopeSwitcher(info, None, self.table, obj.position)
arguments = ExpList(base_exp, None, obj.position)
for expr in obj.expr_list:
expr.accept(self)
arguments = ExpList(
self.main_subtree.to_exp(),
arguments,
obj.position
)
self.type_stack_visitor.pop_type_from_stack()
class_info = self.table.get_class(info.user_class_name)
method_address = class_info.class_struct.get_virtual_method_address(
obj.id.name,
Temp(None, None, base_address),
obj.position,
)
self.main_subtree = ExpWrapper(Call(method_address, arguments, obj.position))
self.type_stack_visitor.visit(obj)
type_switcher.destroy()
def visit_new_int_array_expr(self, obj: NewIntArrExpr):
obj.size.accept(self)
self.type_stack_visitor.pop_type_from_stack()
number_of_elements = self.main_subtree.to_exp()
args = ExpList(
Binop(
BinopEnum.MUL,
number_of_elements,
Const(
self.current_frame.type_size(TypeEnum.INT),
obj.position
),
obj.position
)
)
self.main_subtree = ExpWrapper(Call(Name(MALLOC_NAME, obj.position), args, obj.position))
self.type_stack_visitor.visit(obj)
def visit_new_object_expr(self, obj: NewObjectExpr):
class_info = self.table.get_class(obj.id.name)
alloc_actions = class_info.class_struct.allocate_new(obj.position)
self.main_subtree = ExpWrapper(alloc_actions)
self.type_stack_visitor.visit(obj)
def visit_random_access_assign_statement(self, obj: RandomAccessAssignStatement):
obj.position_in_arr.accept(self)
self.type_stack_visitor.pop_type_from_stack()
position_in_arr_expr = self.main_subtree
self.main_subtree = None
obj.expr.accept(self)
access = self.current_frame.find_local_or_formal(obj.id.name)
if access is not None:
base_address = access.get_exp(
Temp(
fp_name, None, None,
obj.position
),
obj.position
)
else:
base_address = self.table.get_scoped_class().class_struct.get_field_from(
obj.id.name,
self.current_frame.find_local_or_formal(THIS_NAME).get_exp(
Temp(fp_name, None, None, obj.position),
obj.position
),
obj.position
)
address = Mem(
Binop(
BinopEnum.PLUS,
base_address,
Binop(
BinopEnum.MUL,
Const(
self.current_frame.type_size(self.current_frame.word_type().type_enum),
obj.position
),
position_in_arr_expr.to_exp(),
obj.position
),
obj.position
),
obj.position
)
self.main_subtree = StmWrapper(Move(address, self.main_subtree.to_exp(), obj.position))
def visit_length_expr(self, obj: LengthExpr):
obj.obj.accept(self)
array_base = self.main_subtree.to_exp()
self.main_subtree = ExpWrapper(array_struct.get_length(array_base, obj.position))
self.type_stack_visitor.visit(obj)
def visit_print_line_statement(self, obj: PrintLineStatement):
obj.obj.accept(self)
self.type_stack_visitor.pop_type_from_stack()
self.main_subtree = ExpWrapper(
Call(
Name(
println_name,
obj.position
),
ExpList(self.main_subtree.to_exp(), None, obj.position),
obj.position
)
)
def visit_if_statement(self, obj: IfStatement):
obj.condition.accept(self)
self.type_stack_visitor.pop_type_from_stack()
else_branch_label = Label.get_next_enumerated_label()
exit_label = Label.get_next_enumerated_label()
condition = self.main_subtree.to_conditional(JumpTypeEnum.NEQ, else_branch_label)
obj.if_true.accept(self)
if_part = Seq(
self.main_subtree.to_stm(),
Jump(exit_label, obj.position),
obj.position
)
obj.if_false.accept(self)
else_part = Seq(
Seq(
LabelStm(else_branch_label, obj.position),
self.main_subtree.to_stm(),
obj.position
),
Jump(exit_label, obj.position),
obj.position
)
self.main_subtree = StmWrapper(
Seq(
Seq(
condition,
Seq(
if_part,
else_part,
obj.position
),
obj.position
),
LabelStm(exit_label, obj.position),
obj.position
)
)
def visit_while_statement(self, obj: WhileStatement):
obj.condition.accept(self)
condition_label = Label.get_next_enumerated_label()
exit_label = Label.get_next_enumerated_label()
condition = self.main_subtree.to_conditional(JumpTypeEnum.NEQ, exit_label)
condition_part = Seq(LabelStm(condition_label, obj.position),
condition, obj.position)
obj.action.accept(self)
body_part = Seq(
self.main_subtree.to_stm(),
Jump(condition_label, obj.position),
obj.position
)
self.main_subtree = StmWrapper(
Seq(
Seq(
condition_part,
body_part,
obj.position
),
LabelStm(
exit_label,
obj.position
),
obj.position
)
)
def visit_statements(self, obj: Statements):
statements = []
for statement in obj.statement_list:
statement.accept(self)
statements.append(self.main_subtree.to_stm())
assert len(statements) > 0
if len(statements) == 1:
self.main_subtree = StmWrapper(statements[0])
else:
seq = Seq(statements[0], statements[1], obj.position)
for i in range(2, len(statements), 1):
seq = Seq(seq, statements[i], obj.position)
self.main_subtree = StmWrapper(seq)
def visit_random_access_expr(self, obj: RandomAccessExpr):
obj.object.accept(self)
array_base = self.main_subtree.to_exp()
obj.position_in_arr.accept(self)
element_number = self.main_subtree.to_exp()
self.main_subtree = ExpWrapper(array_struct.get_element(array_base, element_number, obj.position))
self.type_stack_visitor.visit(obj)
def visit_this_expr(self, obj: ThisExpr):
self.main_subtree = ExpWrapper(
Mem(
self.current_frame.find_local_or_formal(THIS_NAME).get_exp(
Temp(fp_name, None, None, obj.position),
obj.position
),
obj.position
)
)
self.type_stack_visitor.visit(obj)
def visit_return_statement(self, obj: ReturnStatement):
obj.expression.accept(self)
self.type_stack_visitor.pop_type_from_stack()
return_address = self.current_frame.return_address.get_exp(
Temp(fp_name, None, None, obj.position),
obj.position
)
self.main_subtree = StmWrapper(Move(return_address, self.main_subtree.to_exp(), obj.position))
def visit_stm_wrapper(self, obj: StmWrapper):
obj.to_stm().accept(self)