Virtual unifed instruction and data caches including storing program instructions and memory address in CAM indicated by store instruction containing bit directly indicating self modifying code

Execution of a store instruction to modify an instruction at a memory location identified by a memory address is requested. A cache controller stores the memory address and the modified data in an associative memory coupled to a data cache and an instruction cache. In addition, the modified data is stored in a second level cache without invalidating the memory location associated with the instruction cache.