OPCODES = {}

def add_opcode (*opcode_names):
	def wrapped (func):
		for name in opcode_names:
			OPCODES[name] = func
	return wrapped

################################################################################

# Stack

@add_opcode("push","pushq")
def push(emu, value):
	emu.pushToStack(emu.getVal(value))

@add_opcode("pop","popq")
def pop(emu, target_reg):
	emu.registers[target_reg] = emu.popFromStack()
	emu.changedRegisters((target_reg,"change"))

# Arithmetic

@add_opcode("mov","movq")
def mov(emu, from_reg, target_reg):
	emu.registers[target_reg] = emu.getVal(from_reg)
	emu.changedRegisters((target_reg,"change"))

@add_opcode("add","addq")
def add(emu, add_val, target_reg):
	emu.registers[target_reg] += emu.getVal(add_val)
	emu.changedRegisters((target_reg,"change"))

@add_opcode("sub","subq")
def sub(emu, sub_val, target_reg):
	emu.registers[target_reg] -= emu.getVal(sub_val)
	emu.changedRegisters((target_reg,"change"))

# Comparison and conditional jumping

@add_opcode("cmp","cmpq")
def comp(emu, val1, val2):
	emu.compareVal(val1, val2)

@add_opcode("jg")
def jg(emu, label):
	emu.jump(label, g=True)

@add_opcode("jl")
def jl(emu, label):
	emu.jump(label, l=True)

@add_opcode("je")
def je(emu, label):
	emu.jump(label, e=True)

@add_opcode("jge")
def jge(emu, label):
	emu.jump(label, "or", g=True, e=True)

@add_opcode("jle")
def jle(emu, label):
	emu.jump(label, "or", l=True, e=True)

@add_opcode("jne")
def jne(emu, label):
	emu.jump(label, e=False)

# Unconditional Jumping

@add_opcode("jmp")
def jmp(emu, label):
	emu.registers['%rip'] = emu.labels[label]

@add_opcode("call")
def call(emu, label):
	emu.pushToStack(emu.registers['%rip']+1)
	emu.registers['%rip'] = emu.labels[label]

@add_opcode("leave")
def leave(emu):
	emu.registers["%rsp"] = emu.registers["%rbp"]
	emu.registers["%rbp"] = emu.popFromStack()

@add_opcode("ret")
def ret(emu):
	emu.registers['%rip'] = emu.popFromStack()