OPCODE LENGTH CACHING

A computer system caches variable-length instructions in a data structure. The computer system locates a first copy of an instruction in the cached data structure using a current value of the instruction pointer as a key. The computer system determines a predictive length of the instruction, and reads a portion of the instruction from an instruction memory as a second copy. The second copy has the predictive length. Based on the comparison of the first copy with the second copy, the computer system determines whether or not to read the rest of the instruction from the instruction memory, and then interprets the instruction for use by the computer system.