An apparatus and method for ensuring coherency of instructions within
stages of the pipeline microprocessor. The apparatus includes instruction
cache management logic and synchronization logic. The instruction cache
management logic receives an address corresponding to a next instruction
to be fetched, and detects that a part of a memory page corresponding to
the next instruction cannot be freely accessed without checking for
coherency of the instructions within the part of the memory page and,
upon detection, provides the address. The synchronization logic receives
the address from the instruction cache management logic. The
synchronization logic directs data cache management logic to check for
coherency of the instructions within the part of the memory page, and, if
the instructions are not coherent within the part of the memory page, the
synchronization logic directs the pipeline microprocessor to stall a
fetch of the next instruction until the stages of the pipeline.