6.3.7. Prefetching memory

Prefetch from Memory (PRFM) enables code to provide a hint to the memory system that data from a particular address will be used by the program soon. The effect of this hint is implementation defined, but typically, it results in data or instructions being loaded into one of the caches.

The instruction syntax is:

  PRFM <prfop>, <addr> | label

Where prfop is a concatenation of the following options:


PLD or PST (prefetch for load or store).


L1, L2, or L3 (which cache to target).


KEEP or STRM (keep in cache, or streaming data).

For example, PLDL1KEEP.

These instructions are similar to the A32 PLD and PLI instructions.

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