def build_return_statement(self, tree: grammerParser.RContext):
expression = self.build_assignment_expression(tree.getChild(1))
if expression.get_type() == self.symbol_table.get_function_symbol(
self.current_function).get_function_type():
return ReturnStatement(expression)
else:
raise CompilerError('return type error')
def build_init_declarator(self, tree: grammerParser.RContext, type):
if tree.getChildCount() == 3:
identifier, size_list = self.build_declarator(tree.getChild(0))
if len(size_list) > 0:
raise CompilerError('you can init a array')
else:
self.symbol_table.add_variable_name(identifier, type)
variable_expression = VariableExpression(
self.symbol_table.get_variable(identifier))
expression = self.build_assignment_expression(tree.getChild(2))
if variable_expression.get_type() != expression.get_type():
raise CompilerError('type error')
return AssignmentExpression(variable_expression, expression, '=')
else:
identifier, size_list = self.build_declarator(tree.getChild(0))
if len(size_list) > 0:
self.symbol_table.add_variable_name(identifier, type,
size_list)
symbol = self.symbol_table.get_variable(identifier)
code = []
length = reduce(lambda x, y: x * y, size_list)
for i in range(length):
code += [f'lda 0 {symbol.get_address()}']
code += [f'ldc i {i}']
code += [f'ixa 1']
if symbol.get_type() == 'int':
code += [f'ldc i 0']
code += [f'sto i']
elif symbol.get_type() == 'real':
code += [f'ldc r 0.0']
code += [f'sto r']
elif symbol.get_type() == 'bool':
code += [f'ldc b f']
code += [f'sto b']
return PcodeExpression(code)
else:
self.symbol_table.add_variable_name(identifier, type)
variable_expression = VariableExpression(
self.symbol_table.get_variable(identifier))
if type == 'int':
expression = ConstantExpression('0', 'int')
elif type == 'real':
expression = ConstantExpression('0.0', 'real')
else:
expression = ConstantExpression('false', 'bool')
return AssignmentExpression(variable_expression, expression,
'=')
def build_relational_expression(self, tree: grammerParser.RContext):
if tree.getChildCount() == 1:
return self.build_additive_expression(tree.getChild(0))
else:
left_expression = self.build_relational_expression(
tree.getChild(0))
right_expression = self.build_additive_expression(tree.getChild(2))
op = tree.getChild(1).getText()
if left_expression.get_type() == right_expression.get_type(
) and left_expression.get_type() != 'bool':
return ComparisonExpression(left_expression, right_expression,
op)
else:
if left_expression.get_type() != right_expression.get_type():
raise CompilerError('you can only compiler same type')
else:
raise CompilerError('you can only int or real')
def build_unary_expression(self, tree: grammerParser.RContext):
if tree.getChildCount() == 1:
return self.build_postfix_expression(tree.getChild(0))
elif tree.getChild(0).getChildCount() > 0:
op = self.build_unary_operator(tree.getChild(0))
expression = self.build_cast_expression(tree.getChild(1))
if op == '!':
if expression.get_type() == 'bool':
if isinstance(expression, ConstantExpression):
expression.not_value()
return expression
else:
return UnaryExpression(expression, op)
else:
raise CompilerError('！ except bool')
elif op == '-':
if expression.get_type() != 'bool':
if isinstance(expression, ConstantExpression):
expression.negetive_value()
return expression
else:
return UnaryExpression(expression, op)
else:
raise CompilerError('- except int or real')
else:
expression = self.build_unary_expression(tree.getChild(1))
if isinstance(
expression,
VariableExpression) and expression.get_type() == 'int':
return SelfIncrementUnaryExpression(expression,
tree.getChild(0).getText())
else:
raise CompilerError('type error')
def build_multiplicative_expression(self, tree: grammerParser.RContext):
if tree.getChildCount() == 1:
return self.build_cast_expression(tree.getChild(0))
else:
left_expression = self.build_multiplicative_expression(
tree.getChild(0))
right_expression = self.build_cast_expression(tree.getChild(2))
op = tree.getChild(1).getText()
if left_expression.get_type() == right_expression.get_type(
) and left_expression.get_type() != 'bool':
if isinstance(left_expression,
ConstantExpression) and isinstance(
right_expression, ConstantExpression):
if op == '*':
return ConstantExpression(
left_expression.get_value() *
right_expression.get_value(),
left_expression.get_type())
if left_expression.get_type() == 'int':
if op == '/':
return ConstantExpression(
left_expression.get_value() //
right_expression.get_value(),
left_expression.get_type())
elif op == '%':
return ConstantExpression(
left_expression.get_value() %
right_expression.get_value(),
left_expression.get_type())
else:
if op == '/':
return ConstantExpression(
left_expression.get_value() /
right_expression.get_value(),
left_expression.get_type())
else:
raise CompilerError('type error')
if op != '%' and left_expression.get_type() == 'real':
raise CompilerError('you can mod real')
else:
return ArithmeticExpression(left_expression,
right_expression, op)
else:
raise CompilerError('you can\'t calculate bool')
def build_seletion_statement(self, tree: grammerParser.RContext):
condition = self.build_assignment_expression(tree.getChild(2))
if condition.get_type() != 'bool':
raise CompilerError('condition must be bool')
then_statement = self.build_statement(tree.getChild(4))
if not isinstance(then_statement, list):
then_statement = [then_statement]
if tree.getChildCount() == 7:
else_statement = self.build_statement(tree.getChild(6))
if not isinstance(else_statement, list):
else_statement = [else_statement]
self.label += 2
return SelectionStatement(condition, then_statement,
'label' + str(self.label - 2),
else_statement,
'label' + str(self.label - 1))
else:
self.label += 1
return SelectionStatement(condition, then_statement,
'label' + str(self.label - 1))
def build_assignment_expression(self, tree: grammerParser.RContext):
if tree.getChildCount() == 1:
return self.build_logical_or_expression(tree.getChild(0))
else:
identifier, expression_list = self.build_variable_expression(
tree.getChild(0))
op = self.build_assignment_operator(tree.getChild(1))
expression = self.build_assignment_expression(tree.getChild(2))
if self.symbol_table.is_variable_existed(identifier):
symbol = self.symbol_table.get_variable(identifier)
if symbol.get_type() == expression.get_type():
if len(expression_list) > 0:
variable_expression = VariableExpression(
symbol, expression_list)
else:
variable_expression = VariableExpression(symbol)
return AssignmentExpression(variable_expression,
expression, op)
else:
raise CompilerError('type error')
else:
raise CompilerError('variable is not defined')
def build_postfix_expression(self, tree: grammerParser.RContext):
if tree.getChildCount() == 1:
expression = self.build_primary_expression(tree.getChild(0))
return expression
elif tree.getChildCount() == 2:
expression = self.build_postfix_expression(tree.getChild(0))
if isinstance(
expression,
VariableExpression) and expression.get_type() == 'int':
return SelfIncrementPostfixExpression(
expression,
tree.getChild(1).getText())
else:
raise CompilerError('++ except variable')
elif tree.getChildCount() == 3:
function_name = self.build_postfix_expression(tree.getChild(0))
if self.symbol_table.is_function_existed(function_name):
function_symbol = self.symbol_table.get_function_symbol(
function_name)
if function_symbol.is_argument_right([]):
return FunctionCallExpression(function_symbol, [])
else:
raise CompilerError('parameter error')
else:
raise CompilerError('function is not defined')
else:
function_name = self.build_postfix_expression(tree.getChild(0))
argument_expression_list = self.build_argument_expression_list(
tree.getChild(2))
if self.symbol_table.is_function_existed(function_name):
function_symbol = self.symbol_table.get_function_symbol(
function_name)
if function_symbol.is_argument_right(argument_expression_list):
return FunctionCallExpression(function_symbol,
argument_expression_list)
else:
raise CompilerError('parameter error')
else:
raise CompilerError('function is not defined')
def build_statement(self, tree: grammerParser.RContext):
sub_tree: grammerParser.RContext = tree.getChild(0)
if sub_tree.getRuleIndex() == grammerParser.RULE_expression_statement:
return [self.build_expression_statement(sub_tree)]
elif sub_tree.getRuleIndex(
) == grammerParser.RULE_declaration_statement:
return self.build_declaration_statement(sub_tree)
elif sub_tree.getRuleIndex() == grammerParser.RULE_compound_statement:
self.symbol_table.open_scope()
ret = self.build_compound_statement(sub_tree)
self.symbol_table.close_scope()
return ret
elif sub_tree.getRuleIndex() == grammerParser.RULE_return_statement:
return [self.build_return_statement(sub_tree)]
elif sub_tree.getRuleIndex() == grammerParser.RULE_output_statement:
return [self.build_output_statement(sub_tree)]
elif sub_tree.getRuleIndex() == grammerParser.RULE_selection_statement:
return [self.build_seletion_statement(sub_tree)]
elif sub_tree.getRuleIndex() == grammerParser.RULE_iteration_statement:
return [self.build_iteration_statement(sub_tree)]
def build_iteration_statement(self, tree: grammerParser.RContext):
if tree.getChild(0).getText() == 'while':
condition = self.build_assignment_expression(tree.getChild(2))
if condition.get_type() != 'bool':
raise CompilerError('condition must be bool')
after_start = self.build_statement(tree.getChild(4))
if not isinstance(after_start, list):
after_start = [after_start]
self.label += 2
return IterationStatement(condition, f'label{self.label - 2}',
f'label{self.label - 1}', [],
after_start, [])
if tree.getChild(0).getText() == 'do':
condition = self.build_assignment_expression(tree.getChild(4))
if condition.get_type() != 'bool':
raise CompilerError('condition must be bool')
after_start = self.build_statement(tree.getChild(1))
if not isinstance(after_start, list):
after_start = [after_start]
self.label += 2
return IterationStatement(condition, f'label{self.label - 2}',
f'label{self.label - 1}', after_start,
after_start, [])
if tree.getChild(0).getText() == 'repeat':
condition = self.build_assignment_expression(tree.getChild(4))
if condition.get_type() != 'bool':
raise CompilerError('condition must be bool')
condition = UnaryExpression(condition, '!')
after_start = self.build_statement(tree.getChild(1))
if not isinstance(after_start, list):
after_start = [after_start]
self.label += 2
return IterationStatement(condition, f'label{self.label - 2}',
f'label{self.label - 1}', after_start,
after_start, [])
if tree.getChild(0).getText() == 'for' and tree.getChildCount() == 7:
condition = self.build_expression_statement(tree.getChild(3))
if condition.get_type() != 'bool':
raise CompilerError('condition must be bool')
after_start = self.build_statement(tree.getChild(6))
if not isinstance(after_start, list):
after_start = [after_start]
before_end = self.build_assignment_expression(tree.getChild(4))
if not isinstance(before_end, list):
before_end = [before_end]
before_start = self.build_expression_statement(tree.getChild(2))
if not isinstance(before_start, list):
before_start = [before_start]
self.label += 2
return IterationStatement(condition, f'label{self.label - 2}',
f'label{self.label - 1}', before_start,
after_start, before_end)
else:
condition = self.build_expression_statement(tree.getChild(3))
if condition.get_type() != 'bool':
raise CompilerError('condition must be bool')
after_start = self.build_statement(tree.getChild(5))
if not isinstance(after_start, list):
after_start = [after_start]
before_start = self.build_expression_statement(tree.getChild(2))
if not isinstance(before_start, list):
before_start = [before_start]
self.label += 2
return IterationStatement(condition, f'label{self.label - 2}',
f'label{self.label - 1}', before_start,
after_start, [])
def build_output_statement(self, tree: grammerParser.RContext):
expression = self.build_expression_statement(tree.getChild(1))
return OutputStatement(expression)
def build_parameter_declaration(self, tree: grammerParser.RContext):
identifier_type = self.build_declaration_specifiers(tree.getChild(0))
identifier_name = self.build_parameter_declarator(tree.getChild(1))
self.symbol_table.add_variable_name(identifier_name, identifier_type)
return [identifier_type]
def build_unary_operator(self, tree: grammerParser.RContext):
return tree.getText()
def build_assignment_operator(self, tree: grammerParser.RContext):
return tree.getText()
def build_expression_statement(self, tree: grammerParser.RContext):
if tree.getChildCount() == 2:
return self.build_assignment_expression(tree.getChild(0))
else:
return PcodeExpression([])
def build_declaration_specifiers(self, tree: grammerParser.RContext):
return tree.getText()
def build_function_name(self, tree: grammerParser.RContext):
if tree.getPayload().type == grammerLexer.IDENTIFIER:
return tree.getText()
else:
raise
def build_declaration_statement(self, tree: grammerParser.RContext):
if tree.getChildCount() == 3:
type = self.build_declaration_specifiers(tree.getChild(0))
return self.build_init_declarator_list(tree.getChild(1), type)
def build_parameter_declarator(self, tree: grammerParser.RContext):
if tree.getChildCount() != 1:
pass # TODO 函数参数出错
else:
return tree.getText()
def build_compound_statement(self, tree: grammerParser.RContext):
if tree.getChildCount() == 3:
return self.build_statement_list(tree.getChild(1))
else:
pass # TODO 语句为空所做的事情