DATA PROCESSING METHOD, DATA PROCESSING DEVICE, COMPUTER PROGRAM AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To detect an invalid code by revealing an essential structure thereof. SOLUTION: A branch source address and a branch destination address of a branch instruction (jmp instruction) are stored (S4), and whether the branch destination address is connected with a call instruction for calling an instruction code group for executing an external command or not is determined (S6). If the branch destination address is connected with a call instruction, whether the call destination is between the branch source address and the branch destination address or not is determined (S9). If the call destination of the call instruction is between the branch source address and the branch destination address, information to the effect that an invalid code is detected is generated (S10). COPYRIGHT: (C)2004,JPO