Python 代码优化 ➢要求能自动对输入的四元式进行基本块的划分，并对基本块内的代码利用DAG进行优化，生成优化后的四元式代码。可视化基本块的连接以及DAG图

好的，下面是一个能自动对输入的四元式进行基本块划分并利用 DAG 进行优化的 Python 代码： ```python from typing import List from collections import deque class Quadruple: def __init__(self, op: str, arg1: str, arg2: str, res: str): self.op = op self.arg1 = arg1 self.arg2 = arg2 self.res = res def __str__(self): return f'({self.op}, {self.arg1}, {self.arg2}, {self.res})' def split_basic_blocks(quadruples: List[Quadruple]) -> List[List[Quadruple]]: basic_blocks = [] current_block = [] for q in quadruples: current_block.append(q) if q.op == 'goto' or q.op == 'if': basic_blocks.append(current_block) current_block = [] if current_block: basic_blocks.append(current_block) return basic_blocks class DAGNode: def __init__(self, op: str, arg1: str, arg2: str, res: str): self.op = op self.arg1 = arg1 self.arg2 = arg2 self.res = res self.parents = [] self.children = [] def __str__(self): return f'({self.op}, {self.arg1}, {self.arg2}, {self.res})' class DAG: def __init__(self, quadruples: List[Quadruple]): self.nodes = {} self.roots = [] for q in quadruples: if q.op == '=': node = DAGNode(q.op, q.arg1, None, q.res) else: node = DAGNode(q.op, q.arg1, q.arg2, q.res) if node.res in self.nodes: existing_node = self.nodes[node.res] existing_node.parents.append(node) node.children.append(existing_node) self.nodes[node.res] = node else: self.nodes[node.res] = node self.roots.append(node) def generate_code(self) -> List[Quadruple]: optimized_quadruples = [] visited = set() for root in self.roots: