def __init__(self, symtable, threeAC):
self.symtable = symtable
self.code = threeAC.code
self.unused_register = unused_register_list.copy()
# 基本块
self.basic_blocks = []
# 接下来使用
self.next_use = []
# 每个基本块对应一个label名
self.block_label = {}
# {(startline, endline): label_name}
# symbol 被存在哪些寄存器里
self.symbol_register = {}
def handle_return(self, codeline):
line_num, _, lhs, _, _ = codeline
print("[This line]: ", codeline)
# 寄存器存回内存
for op in self.symbol_register:
reg = self.symbol_register[op]
self.asmcode.append(self.store_mem(op, reg, self.scopeStack))
self.symbol_register.clear()
self.allocReg.unused_register = unused_register_list.copy()
topDeleted = self.scopeStack.pop().lower()
# TODO 恢复参数 （引用传递
# : 将返回值放到v0
if lhs == None:
pass
else:
self.asmcode.append(
'lw $v0, -%d($fp)' %
self.symtable[topDeleted].get("_return").offset)
# 指针
self.asmcode.append('addi $sp, $sp, %d' %
(self.symtable[topDeleted].width + 76))
self.asmcode.append('lw $fp, 72($fp)')
# 恢复寄存器
for index in range(8, 24):
# SW R1, 0(R2)
# FIXME:
self.asmcode.append("lw $%s, %d($sp)" % (index, -12 -
(index - 8) * 4))
# 恢复返回地址 ra
self.asmcode.append('move $t8, $ra')
# ra'
self.asmcode.append('lw $ra, -8($sp)')
# FIXME: 需要填好返回值，然后放回ra，最后返还stack上分配的内存，返回
self.asmcode.append('jr $t8') # 这个地方不是跳转到ra，因为ra已经恢复成跳转之后的返回地址了
def tacToasm(self):
for i in range(len(self.allocReg.basic_blocks)):
start, end = self.allocReg.basic_blocks[i]
block_code = self.code[start:end + 1]
for codeline in block_code:
self.asmcode.append('\n# %s' %
' '.join(str(code) for code in codeline))
line_num, operation, lhs, op1, op2 = codeline
if hasattr(lhs, 'reference') and lhs.reference or \
hasattr(op1, 'reference') and op1.reference or \
hasattr(op2, 'reference') and op2.reference:
for op in self.symbol_register:
reg = self.symbol_register[op]
self.asmcode.append(
self.store_mem(op, reg, self.scopeStack))
self.symbol_register.clear()
self.allocReg.unused_register = unused_register_list.copy()
if operation in binary_list:
self.handle_binary(codeline)
elif operation in ['>', '<', '>=', '<=', '=']:
self.handle_cmp(codeline)
elif operation in ['BNE', 'BEQ', 'JMP']:
if codeline == block_code[-1]:
for op in self.symbol_register:
reg = self.symbol_register[op]
self.asmcode.append(
self.store_mem(op, reg, self.scopeStack))
self.handle_jmp(codeline)
self.symbol_register.clear()
self.allocReg.unused_register = unused_register_list.copy(
)
else:
self.handle_jmp(codeline)
elif operation == 'LABEL':
self.handle_label(codeline)
elif operation == 'CALL':
self.handle_call(codeline)
elif operation == 'PARAM':
self.handle_params(codeline)
elif operation == 'REFER':
self.handle_refers(codeline)
elif operation == 'RETURN':
self.handle_return(codeline)
elif operation == 'INPUT':
self.handle_input(codeline)
elif operation in ['PRINT', 'PRINTLN']:
self.handle_print(codeline)
elif operation == 'LOADREF':
self.handle_loadref(codeline)
elif operation == 'STOREREF':
self.handle_storeref(codeline)
if hasattr(lhs, 'reference') and lhs.reference or \
hasattr(op1, 'reference') and op1.reference or \
hasattr(op2, 'reference') and op2.reference:
for op in self.symbol_register:
reg = self.symbol_register[op]
self.asmcode.append(
self.store_mem(op, reg, self.scopeStack))
self.symbol_register.clear()
self.allocReg.unused_register = unused_register_list.copy()
if block_code[-1][1] not in ['JMP', 'BNE', 'BEQ']:
for op in self.symbol_register:
reg = self.symbol_register[op]
self.asmcode.append(
self.store_mem(op, reg, self.scopeStack))
self.symbol_register.clear()
self.allocReg.unused_register = unused_register_list.copy()
def handle_call(self, codeline):
print("[This line]: ", codeline)
for op in self.symbol_register.keys():
reg = self.symbol_register[op]
self.asmcode.append(self.store_mem(op, reg, self.scopeStack))
self.symbol_register.clear()
self.allocReg.unused_register = unused_register_list.copy()
self.paraCounter = 0
# TODO: 访问链：判断两个scope之间的关系
self.scopeStack[-1]
print("****")
print(codeline[4])
print(self.scopeStack[-1])
print('.'.join(self.scopeStack[-1].split('.')[:-1]))
# if codeline[4] == self.scopeStack[-1]:
# # 访问控制 = fp
# pass
if codeline[4] == '.'.join(self.scopeStack[-1].split('.')[:-1]):
# 访问控制 = 当前活动访问控制
# sp - 4 =
self.asmcode.append("# = parent's")
self.asmcode.append('lw $t8, 76($fp)')
self.asmcode.append('sw $t8, 0($sp)')
else:
self.asmcode.append('# = fp')
self.asmcode.append('sw $fp, 0($sp)')
# 访问控制 = fp
# 控制链
self.asmcode.append('sw $fp, -4($sp)')
# ra
self.asmcode.append('sw $ra, -8($sp)')
# sw $ra -8($sp)
# reg
for index in range(8, 24):
# SW R1, 0(R2)
# FIXME:
self.asmcode.append("sw $%s, %d($sp)" % (index, -12 -
(index - 8) * 4))
# param 参数中处理
#
self.asmcode.append('addi $fp $sp -76')
scope_width = self.symtable['%s.%s' %
(codeline[4], codeline[3].lower())].width
self.asmcode.append('addi $sp $sp %d' % -(scope_width + 76))
# jal
# self.asmcode.append("jal %s"%self.symtable[codeline[3]])
self.asmcode.append("jal %s" % codeline[3])
# 将返回值从 $v0 中取出
if codeline[2]:
block_index = self.allocReg.line_block(codeline[0])
reg_lhs = self.handle_term(codeline[2], block_index, codeline[0])
self.asmcode.append("move, {}, $v0".format(reg_lhs))