You copied the Doc URL to your clipboard.

17.52 PRFM (register)

Prefetch memory (register offset).

Syntax

PRFM prfop, [Xn|SP, Rm{, extend {amount}}]

Where:

prfop

Is the prefetch operation, and contains the following fields without spaces between them:

type target policy

type

Can be one of:

Table 17-15 PRFM (register) type options

optionmeaning
PLDprefetch for load
PSTprefetch for store
target

Can be one of:

Table 17-16 PRFM (register) target options

optionmeaning
L1Level 1 cache
L2Level 2 cache
L3Level 3 cache
policy

Can be one of:

Table 17-17 PRFM (register) policy options

optionmeaning
KEEPkeep in cache
STRMStreaming data

For example, PLDL1KEEP.

Xn|SP

Is the 64-bit name of the general-purpose base register or stack pointer.

R

Is the index width specifier, and can be either W or X.

m

Is the number [0-30] of the general-purpose index register or the name ZR (31).

extend

Is the index extend/shift specifier, defaulting to LSL, and can be one of the values shown in Usage.

amount

Is the index shift amount, optional and defaulting to #0 when extend is not LSL, and can be either #0 or #3.

Usage

The following table shows the valid specifier combinations:

Table 17-18 PRFM specifier combinations

Rextend
WSXTW
WUXTW
XLSL
XSXTX