PURPOSE: To decrease the quantity of information transferred between a main storage part and a processor by providing a storing part for the pre-fetch information on the destination branched by a branch instruction at each stage of a pre-fetching process in order to reproduce the branch instruction executed previously at a high speed and also performing the transfer of data between a storing part serving as an internal memory part and a register.

CONSTITUTION: A storing part which stores the information on the branch processing is provided together with an associative memory part 19 which registers a storage for branch processing information with the address of a registered branch instruction used as a key ann then delivers it when the registered branch instruction is delivered, and an executing part 13 which judges a registered or non-registered branch instruction and controls it. If the branch instruction is registered in the first branch processing mode, it is transferred to the storing part from a temporary storing part. Then the branch instruction is transferred to the temporary storing part from the storing part thereafter by the output information on the part 19.