Legacy Document

Inside Macintosh: Memory /

Chapter 4 - Memory Management Utilities / Memory Management Utilities Reference

Routines / Manipulating the Processor Caches

FlushInstructionCache

You can use the FlushInstructionCache procedure to flush the instruction cache.

PROCEDURE FlushInstructionCache;

DESCRIPTION

The FlushInstructionCache procedure flushes the current contents of the instruction cache. Because flushing this cache degrades performance of the CPU, you should call this routine only when absolutely necessary. See "Stale Instructions" on page 4-9 for details on when to call this procedure.

ASSEMBLY-LANGUAGE INFORMATION

The trap macro and routine selector for FlushInstructionCache are

Trap macro	Selector
_HWPriv	$0001

SPECIAL CONSIDERATIONS

On processors with a copy-back data cache, FlushInstructionCache also flushes the data cache before it flushes the instruction cache, to ensure that any instructions subsequently copied to the instruction cache are not copied from stale RAM.