A.5.249 PREFETCHh: Prefetch Data Into Caches
PREFETCHNTA m8 ; 0F 18 /0 [KATMAI]
PREFETCHT0 m8 ; 0F 18 /1 [KATMAI]
PREFETCHT1 m8 ; 0F 18 /2 [KATMAI]
PREFETCHT2 m8 ; 0F 18 /3 [KATMAI]
The PREFETCHh instructions fetch the line of data from memory that
contains the specified byte. It is placed in the cache according to
rules specified by locality hints "h":
The hints are:
- T0 (temporal data) - prefetch data into all levels of the cache
hierarchy.
- T1 (temporal data with respect to first level cache) - prefetch data
into level 2 cache and higher.
- T2 (temporal data with respect to second level cache) - prefetch
data into level 2 cache and higher.
- NTA (non-temporal data with respect to all cache levels) - prefetch
data into non-temporal cache structure and into a location close to
the processor, minimizing cache pollution.
Note that this group of instructions doesn't provide a guarantee that
the data will be in the cache when it is needed. For more details, see
the Intel IA32 Software Developer Manual, Volume 2.