def decode_var_int(data, size):
"""
LEB128有符号整数解码
:param data: 解码后的整数
:param size: 实际消耗的字节数
:return:
"""
result = 0
for i, b in enumerate(data):
if i == int(size / 7):
if b & 0x80 != 0:
raise ErrIntTooLong
if b & 0x40 == 0 and b >> (size - i * 7 - 1) != 0 or \
b & 0x40 != 0 and int8(b | 0x80) >> (size - i * 7 - 1) != -1:
raise ErrIntTooLarge
result |= (b & 0x7f) << (i * 7)
if b & 0x80 == 0:
if (i * 7 < size) and (b & 0x40 != 0):
result |= -1 << ((i + 1) * 7)
return result, i + 1
raise ErrUnexpectedEnd
def i64_load_8s(vm, mem_arg):
val = read_u8(vm, mem_arg)
vm.push_s64(int64(int8(val)))
def i32_load_8s(vm, mem_arg):
val = read_u8(vm, mem_arg)
vm.push_u32(int32(int8(val)))
def i64_extend_8s(vm, _):
vm.push_s64(int64(int8(vm.pop_s64())))
def i32_extend_8s(vm, _):
vm.push_s32(int32(int8(vm.pop_s32())))