Cache Prefetch Hint

Hint that a cache line should be brought closer to the core before it is used.

Memory System

Semantics

A performance hint with no architectural effect: it may be ignored, and it never faults on an inaccessible address.

Architecture Instructions Expressed as How this architecture does it
x86 one instruction The suffix selects a cache-level hint: T0 through T2 target the cache hierarchy, NTA marks the data as non-temporal.
ARM one instruction One instruction with a structured hint operand encoding type (load/store/instruction), target level, and retention policy, for example PRFM PLDL1KEEP.
RISC-V one instruction Zicbop. The read and write forms are separate instructions rather than a hint field.
PowerISA one instruction dcbt hints a read and dcbtst a forthcoming write; both are base data cache block touch instructions.