Introduce middle-end

.gitignore

@@ -45,3 +45,7 @@ tmp
 GPATH
 GRTAGS
 GTAGS
+
+__init__.py
+
+*.pyc

src/pysrc/requirements.txt

@@ -0,0 +1 @@
+llvmlite==0.41.0

src/pysrc/sysy/backend/x86_emitter.py

@@ -0,0 +1,27 @@
+class X86Emitter:
+    def __init__(self):
+        self.reg_pool = ["eax", "ebx", "ecx", "edx"]  # 简化寄存器分配
+    
+    def emit_function(self, func: MiddleFunction) -> str:
+        asm = [f".globl {func.name}", f"{func.name}:"]
+        for block in func.basic_blocks:
+            asm.append(f".{block.name}:")
+            for instr in block.instructions:
+                asm.append(self.emit_instruction(instr))
+        return "\n".join(asm)
+    
+    def emit_instruction(self, instr: MiddleInstruction) -> str:
+        op = instr.opcode
+        if op == "add":
+            dest, src1, src2 = instr.operands
+            return f"  addl {self.map_operand(src2)}, {self.map_operand(dest)}"
+        elif op == "ret":
+            return "  ret"
+        else:
+            raise NotImplementedError(f"Unsupported opcode: {op}")
+    
+    def map_operand(self, operand: str) -> str:
+        """将虚拟寄存器映射到物理寄存器（简化版）"""
+        if operand.startswith('%'):
+            return self.reg_pool[int(operand[1:]) % len(self.reg_pool)]
+        return operand

src/pysrc/sysy/middle_ir.py

@@ -0,0 +1,14 @@
+class MiddleFunction:
+    def __init__(self, name: str):
+        self.name = name
+        self.basic_blocks = []  # List[MiddleBasicBlock]
+
+class MiddleBasicBlock:
+    def __init__(self, name: str):
+        self.name = name
+        self.instructions = []  # List[MiddleInstruction]
+
+class MiddleInstruction:
+    def __init__(self, opcode: str, operands: list):
+        self.opcode = opcode    # e.g., 'add', 'ret'
+        self.operands = operands # e.g., ['%0', '%1', '%2']

src/pysrc/sysy/utils/ir_parser.py

@@ -0,0 +1,22 @@
+from llvmlite import ir
+
+def parse_llvm_ir(ir_text: str) -> MiddleFunction:
+    """将 LLVM IR 文本转换为 MiddleIR 结构（简化版）"""
+    module = ir.Module()
+    module.parse(ir_text)
+    
+    # 提取第一个函数
+    func = list(module.functions)[0]
+    middle_func = MiddleFunction(func.name)
+    
+    # 转换基本块和指令
+    for block in func.blocks:
+        mid_block = MiddleBasicBlock(block.name)
+        for instr in block.instructions:
+            opcode = instr.opcode
+            operands = [str(op) for op in instr.operands]
+            mid_instr = MiddleInstruction(opcode, operands)
+            mid_block.instructions.append(mid_instr)
+        middle_func.basic_blocks.append(mid_block)
+    
+    return middle_func

src/pysrc/sysyc.py

@@ -0,0 +1,23 @@
+import sys
+from sysy.utils.ir_parser import parse_llvm_ir
+from sysy.backend.x86_emitter import X86Emitter
+
+def main():
+    if len(sys.argv) != 3:
+        print("Usage: sysyc.py <input.ll> <output.s>")
+        sys.exit(1)
+    
+    # 读取 LLVM IR
+    with open(sys.argv[1], 'r') as f:
+        ir_text = f.read()
+    
+    # 解析并生成汇编
+    func = parse_llvm_ir(ir_text)
+    asm = X86Emitter().emit_function(func)
+    
+    # 写入文件
+    with open(sys.argv[2], 'w') as f:
+        f.write(asm)
+
+if __name__ == "__main__":
+    main()

src/pysrc/tests/test_add.ll

@@ -0,0 +1,5 @@
+define i32 @add(i32 %a, i32 %b) {
+entry:
+  %sum = add i32 %a, %b
+  ret i32 %sum
+}