16.66 DC

Data Cache operation.

This instruction is an alias of SYS.

The equivalent instruction is SYS #op1, C7, Cm, #op2, Xt.


DC <dc_op>, Xt


Is a DC instruction name, as listed for the DC system instruction group, and can be one of the values shown in Usage.
Is a 3-bit unsigned immediate, in the range 0 to 7.
Is a name Cm, with m in the range 0 to 15.
Is a 3-bit unsigned immediate, in the range 0 to 7.
Is the 64-bit name of the general-purpose source register.


Data Cache operation. For more information, see A64 system instructions for cache maintenance in the ARM Architecture Reference Manual ARMv8, for ARMv8-A architecture profile.

The following table shows the valid specifier combinations:

Table 16-7 SYS parameter values corresponding to DC operations

<dc_op> op1 Cm op2
CISW 0 14 2
CIVAC 3 14 1
CSW 0 10 2
CVAC 3 10 1
CVAP 3 12 1
CVAU 3 11 1
ISW 0 6 2
IVAC 0 6 1
ZVA 3 4 1
Non-ConfidentialPDF file icon PDF versionARM 100069_0608_00_en
Copyright © 2014–2017 ARM Limited or its affiliates. All rights reserved.