Patent ID: 7412593

Claim:
A processor for processing a program with commands, the program comprises a mother program with a sub-program jump command and a sub-program, which is to be executed in response to the sub-program jump command, comprising: a command processor adapted to, upon the occurrence of the sub-program jump command in the mother program, extract, from the sub-program jump command, back-up information about data required in the mother program after processing the sub-program; back-up, based on the back-up information, the data required in the mother program after processing the sub-program; extract a destination address referring to the sub-program from the sub-program jump command; effect, based on the destination address, the processing of the program to be continued with the sub-program; and a log unit adapted to set a mark for every memory location, to which an intermediate value has been stored during the processing of the mother program, wherein the command processor is adapted to back up the intermediate results of those memory locations during back up for which a mark is set, minus the intermediate result of those memory locations which are indicated by the back-up information.