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Assembler Reference
NOP
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| Home > ARM and Thumb Instructions > NOP | |||
No Operation.
SyntaxNOP 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 (ARM)
or MOV r8, r8 (Thumb).
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 ARM, or a 32-bit
boundary in Thumb.
This ARM instructions are available in ARMv6K and above.
This 32-bit Thumb instruction is available in ARMv6T2 and above.
This 16-bit Thumb instruction is available in ARMv6T2 and above.
NOP is available on all other ARM and Thumb architectures
as a pseudo-instruction.
- Reference
| Copyright © 2011-2012 ARM. All rights reserved. | ARM DUI 0588B |
| Non-Confidential | ID062912 |
 PDF version | |
| Home > ARM and Thumb Instructions > NOP |
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