13.75 NOP

No Operation.




is an optional condition code.


NOP does nothing. If NOP is not implemented as a specific instruction on your target architecture, the assembler treats it as a pseudo-instruction and generates an alternative instruction that does nothing, such as MOV r0, r0 (A32) or MOV r8, r8 (T32).

NOP is not necessarily a time-consuming NOP. The processor might remove it from the pipeline before it reaches the execution stage.

You can use NOP for padding, for example to place the following instruction on a 64-bit boundary in A32, or a 32-bit boundary in T32.


This instruction is available in A32 and T32.

Non-ConfidentialPDF file icon PDF versionDUI0801J
Copyright © 2014–2017, 2019 Arm Limited or its affiliates. All rights reserved.