def primary(self, cursor: TokenOperator) -> Node:
"""
primary具象構文木
primary = num | identifier | "(" expression ")"
"""
# (expr)
if cursor.consume("("):
node = self.expression(cursor)
if cursor.consume(")") is False:
raise ValueError("トークンのカッコが左右で対応していません")
return node
# identifier
if cursor.chack_type(TokenKind.IDENTIFIER):
value = cursor.get_value()
cursor.proceed_cursor()
new_node = self.create_new_node(value, NodeKind.LOCAL_VAR, None,
None)
new_node.offset = (ord(value) - ord("a") + 1) * 8
return new_node
if cursor.chack_type(TokenKind.NUMBER) is False:
raise TypeError("数値型のトークンではありません")
# num
value = cursor.get_value()
cursor.proceed_cursor()
return self.create_new_node(value, NodeKind.NUMBER, None, None)
def mul(self, cursor: TokenOperator) -> Node:
"""
mul具象構文木
mul = unary("*" unary | "/" unary)*
"""
node = self.unary(cursor)
while 1:
if cursor.consume("*"):
node = self.create_new_node("*", NodeKind.MUL, node, self.unary(cursor))
elif cursor.consume("/"):
node = self.create_new_node("/", NodeKind.DIV, node, self.unary(cursor))
else:
return node
def add(self, cursor: TokenOperator) -> Node:
"""
add具象構文木
add = mul("+" mul| "-" mul)*
"""
node = self.mul(cursor)
while 1:
if cursor.consume("+"):
node = self.create_new_node("+", NodeKind.ADD, node, self.mul(cursor))
elif cursor.consume("-"):
node = self.create_new_node("-", NodeKind.SUB, node, self.mul(cursor))
else:
return node
def equality(self, cursor: TokenOperator) -> Node:
"""
equality具象構文木
equality = relation ("==" relation | "!=" relation)*
"""
node = self.relation(cursor)
while 1:
if cursor.consume("=="):
node = self.create_new_node("==", NodeKind.EQUAL, node, self.relation(cursor))
elif cursor.consume("!="):
node = self.create_new_node("!=", NodeKind.NOT_EQUAL, node, self.relation(cursor))
else:
return node
def unary(self, cursor: TokenOperator) -> Node:
"""
unary具象構文木
unary = ("+" | "-")? primary
"""
if cursor.consume("+"):
return self.primary(cursor)
if cursor.consume("-"):
return self.create_new_node(
None,
NodeKind.SUB,
self.create_new_node(0, NodeKind.NUMBER, None, None),
self.primary(cursor),
)
return self.primary(cursor)
def main(argv: list) -> int:
"""main関数"""
if len(argv) != 2:
raise ValueError("引数の個数が正しくありません")
operator = TokenOperator(tokenize(argv[1]))
parser = Parser(operator)
nodes = parser.run()
generate_code(nodes)
def relation(self, cursor: TokenOperator) -> Node:
"""
relation具象構文木
relation = add ("<" add | "<=" add | ">" add | ">=" add )*
"""
node = self.add(cursor)
while 1:
if cursor.consume(">="):
node = self.create_new_node(">=", NodeKind.GREATER_EQUAL, node, self.add(cursor))
elif cursor.consume(">"):
node = self.create_new_node(">", NodeKind.GREATER, node, self.add(cursor))
elif cursor.consume("<="):
node = self.create_new_node("<=", NodeKind.LOWER_EQUAL, node, self.add(cursor))
elif cursor.consume("<"):
node = self.create_new_node("<", NodeKind.LOWER, node, self.add(cursor))
else:
return node
def program(self, cursor: TokenOperator) -> List[Node]:
"""
program具象構文木
program = statement*
"""
nodes = []
while cursor.chack_type(TokenKind.EOF) is False:
nodes.append(self.statement(cursor))
return nodes
def statement(self, cursor: TokenOperator) -> Node:
"""
statement具象構文木
statement = expression ";"
"""
node = self.expression(cursor)
if cursor.consume(";") is False:
raise ValueError("プログラムの末尾が;で終わっていません")
return node
def assign(self, cursor: TokenOperator) -> Node:
"""
assign具象構文木
assign = equality ("=" assign)?
"""
node = self.equality(cursor)
if cursor.consume("="):
node = self.create_new_node("=", NodeKind.ASSIGN, node, self.assign(cursor))
return node