def visit(self, node: LogicalExpression):
self.visit(node[0])
self.visit(node[2])
op = node[1]
if op == AND:
self.context.add_opcode(OPCode(OPCodeType.BOOLEAN_AND))
elif op == OR:
self.context.add_opcode(OPCode(OPCodeType.BOOLEAN_OR))
def visit(self, node: ProcedureStatement):
for child in node:
self.visit(child)
self.context.add_opcode(OPCode(OPCodeType.PUSH, [node.proc_name]))
self.context.add_opcode(
OPCode(OPCodeType.CALL, [
len(node.arguments_node)
if node.arguments_node is not None else 0
]))
def visit(self, node: AdditiveExpression):
for index in range(0, len(node) - 1, 2):
self.visit(node[index])
self.visit(node[index + 2])
op = node[index + 1]
if op == ADD:
self.context.add_opcode(OPCode(OPCodeType.SUM))
elif op == SUB:
self.context.add_opcode(OPCode(OPCodeType.SUBTRACT))
def visit(self, node: MultiplicativeExpression):
for index in range(0, len(node) - 1, 2):
self.visit(node[index])
self.visit(node[index + 2])
op = node[index + 1]
if op == MUL:
self.context.add_opcode(OPCode(OPCodeType.MULTIPLY))
elif op == DIV:
self.context.add_opcode(OPCode(OPCodeType.DIVIDE))
elif op == MOD:
self.context.add_opcode(OPCode(OPCodeType.MODULO))
def visit(self, node: SubprogramDeclaration):
for child in node:
self.visit(child)
if node.header.is_function:
# If function have return type - returning Variable with function name
self.context.add_opcode(
OPCode(OPCodeType.PUSH, [node.header.proc_name]))
self.context.add_opcode(OPCode(OPCodeType.RETURN, [1]))
else:
# If function dont have return type - returning nil
self.context.add_opcode(OPCode(OPCodeType.PUSH, ['nil']))
self.context.add_opcode(OPCode(OPCodeType.RETURN, [1]))
self.context.add_opcode(OPCode(OPCodeType.END_SCOPE))
def visit(self, node: RelationalExpression):
self.visit(node[0])
self.visit(node[2])
op = node[1]
if op == LT:
self.context.add_opcode(OPCode(OPCodeType.COMPARE_LT))
elif op == LE:
self.context.add_opcode(OPCode(OPCodeType.COMPARE_LE))
elif op == GT:
self.context.add_opcode(OPCode(OPCodeType.COMPARE_GT))
elif op == GE:
self.context.add_opcode(OPCode(OPCodeType.COMPARE_GE))
elif op == EQ:
self.context.add_opcode(OPCode(OPCodeType.COMPARE_EQ))
elif op == NEQ:
self.context.add_opcode(OPCode(OPCodeType.COMPARE_NEQ))
def visit(self, node: WhileStatement):
self.context.add_opcode(OPCode(OPCodeType.BEGIN_SCOPE))
condition_address = self.context.current_address
self.visit(node.cond_expr)
self.context.add_opcode(OPCode(OPCodeType.JUMP_NEG, [-1]))
jump_fail_opcode = self.context.current_opcode
self.context.add_opcode(OPCode(OPCodeType.BEGIN_SCOPE))
self.visit(node.while_stmt)
self.context.add_opcode(OPCode(OPCodeType.JUMP, [-1]))
jump_condition_opcode = self.context.current_opcode
self.context.add_opcode(OPCode(OPCodeType.END_SCOPE))
fail_address = self.context.current_address + 1
jump_condition_opcode.args[0] = condition_address
jump_fail_opcode.args[0] = fail_address
self.context.add_opcode(OPCode(OPCodeType.END_SCOPE))
def visit(self, node: IfStatement):
self.context.add_opcode(OPCode(OPCodeType.BEGIN_SCOPE))
self.visit(node.cond_expr)
self.context.add_opcode(OPCode(OPCodeType.JUMP_NEG, [-1]))
jump_fail_opcode = self.context.current_opcode
fail_address = self.context.current_address + 1
self.visit(node.if_body_stmt)
self.context.add_opcode(OPCode(OPCodeType.JUMP, [-1]))
jump_complete_opcode = self.context.current_opcode
self.context.add_opcode(OPCode(OPCodeType.END_SCOPE))
if node.else_body_stmt is not None:
self.context.add_opcode(OPCode(OPCodeType.BEGIN_SCOPE))
fail_address = self.context.current_address + 1
self.visit(node.else_body_stmt)
self.context.add_opcode(OPCode(OPCodeType.END_SCOPE))
complete_address = self.context.current_address + 1
jump_complete_opcode.args[0] = complete_address
jump_fail_opcode.args[0] = fail_address
def visit(self, node: Program):
self.context.add_opcode(OPCode(OPCodeType.BEGIN_SCOPE))
for child in node:
self.visit(child)
self.context.add_opcode(OPCode(OPCodeType.END_SCOPE))
def visit(self, node: SubprogramHeader):
self.context.add_opcode(OPCode(OPCodeType.FUNCTION, [node.proc_name]))
self.context.add_opcode(OPCode(OPCodeType.BEGIN_SCOPE))
if node.proc_params is not None:
self.visit(node.proc_params)
def visit(self, node: Factor):
for child in node:
self.visit(child)
if isinstance(node[0], Not):
self.context.add_opcode(OPCode(OPCodeType.BOOLEAN_NOT))
def visit(self, node: VariableDeclaration):
for var_name in node.var_identifiers:
self.context.add_opcode(
OPCode(OPCodeType.DECLARE_LOCAL, [var_name]))
def visit(self, node: SignedFactor):
for child in node:
self.visit(child)
self.context.add_opcode(OPCode(OPCodeType.MINUS))
def visit(self, node: BooleanConstant):
self.context.add_opcode(
OPCode(OPCodeType.PUSH, [str(node.value).lower()]))
def visit(self, node: StringConstant):
self.context.add_opcode(
OPCode(OPCodeType.PUSH, ["\"" + str(node.value).lower() + "\""]))
def visit(self, node: ForStatement):
self.context.add_opcode(OPCode(OPCodeType.BEGIN_SCOPE))
self.visit(node.initial_expression)
self.context.add_opcode(
OPCode(OPCodeType.ASSIGN, [node.variable.variable_name]))
loop_iteration_address = self.context.current_address + 1
self.visit(node.final_expression)
self.context.add_opcode(
OPCode(OPCodeType.PUSH, [node.variable.variable_name]))
if (node.to_downto == 'to'):
self.context.add_opcode(OPCode(OPCodeType.COMPARE_GE))
else:
self.context.add_opcode(OPCode(OPCodeType.COMPARE_LE))
self.context.add_opcode(OPCode(OPCodeType.JUMP_NEG, [-1]))
jump_to_loop_end_opcode = self.context.current_opcode
self.visit(node.for_stmt)
if (node.to_downto == 'to'):
self.context.add_opcode(OPCode(OPCodeType.PUSH, ['1']))
self.context.add_opcode(
OPCode(OPCodeType.PUSH, [node.variable.variable_name]))
self.context.add_opcode(OPCode(OPCodeType.SUM))
else:
self.context.add_opcode(
OPCode(OPCodeType.PUSH, [node.variable.variable_name]))
self.context.add_opcode(OPCode(OPCodeType.PUSH, ['1']))
self.context.add_opcode(OPCode(OPCodeType.SUBTRACT))
self.context.add_opcode(
OPCode(OPCodeType.ASSIGN, [node.variable.variable_name]))
self.context.add_opcode(
OPCode(OPCodeType.JUMP, [loop_iteration_address]))
self.context.add_opcode(OPCode(OPCodeType.END_SCOPE))
jump_to_loop_end_opcode.args[0] = self.context.current_address
def visit(self, node: Parameters):
for ident in reversed(node[:-1]):
self.context.add_opcode(OPCode(OPCodeType.ASSIGN, [ident[0]]))
def visit(self, node: AssignmentStatement):
self.visit(node.right)
self.context.add_opcode(
OPCode(OPCodeType.ASSIGN, [node.left.variable_name]))
def visit(self, node: EntireVariable):
self.context.add_opcode(OPCode(OPCodeType.PUSH, [node.variable_name]))