Patent attributes
A data processing device associates a test module with a sequence of instructions, the test module producing a test result by performing a test on a sequence of instructions. In the sequence of instructions, a first instruction comprising a target address is replaced with a second instruction having an instruction address in the sequence, the second instruction to transfer control to the test module. The target address is stored within an encrypted table, and the test module locates the target address in the table and transfers control to the target address when the test result indicates the sequence of instructions may proceed.