Embodiments of the present disclosure provide an instruction processing apparatus, comprising a first register configured to store a source string, wherein the source string comprises at least one byte, and an execution circuitry, communicatively coupled to the first register and configured to execute a comparison instruction to compare the at least one byte in the source string with an ending identifier to obtain a result value corresponding to the source string, wherein the comparison instruction is executed on each of the at least one byte in the source string and the comparison instruction is an assembly code instruction.