Processor instructions for data compression and decompression

A processor that includes compression instructions to compress multiple adjacent data blocks of uncompressed read-only data stored in memory into one compressed read-only data block and store the compressed read-only data block in multiple adjacent blocks in the memory is provided. During execution of an application to operate on the read-only data, one of the multiple adjacent blocks storing the compressed read-only block is read from memory, stored in a prefetch buffer and decompressed in the memory controller. In response to a subsequent request during execution of the application for an adjacent data block in the compressed read-only data block, the uncompressed adjacent block is read directly from the prefetch buffer.