Data processing system having branch instruction prefetching performance

Abstract

In a data processing system there are provided a main memory device for storing information, a plurality of buffer memory devices including a plurality of blocks for storing a copy of information stored in the main memory device, an arithmetic operation controller including at least one block corresponding to at least one of the blocks of the buffer memory devices for executing instructions including a branch instruction, a branch direction control memory device for storing branch direction information obtained by executing the branch instruction and a preceding controller. The preceding controller comprises a read out means for reading out from the buffer memory devices branch direction information together with a prefetched instruction predicting means for predicting whether a branching will be successful or not.