NOP -- AArch32

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NOP

No Operation does nothing. This instruction can be used for instruction alignment purposes.

Note

The timing effects of including a NOP instruction in a program are not guaranteed. It can increase execution time, leave it unchanged, or even reduce it. Therefore, NOP instructions are not suitable for timing loops.

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 and T2 ) .

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
!= 1111				0	0	1	1	0	0	1	0	0	0	0	0	(1)	(1)	(1)	(1)	(0)	(0)	(0)	(0)	0	0	0	0	0	0	0	0
cond									R			imm4								imm12

Decode for this encoding

15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
1	0	1	1	1	1	1	1	0	0	0	0	0	0	0	0
		hint

15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
1	1	1	1	0	0	1	1	1	0	1	0	(1)	(1)	(1)	(1)	1	0	(0)	0	(0)	0	0	0	0	0	0	0	0	0	0	0
																								hint				option

Decode for this encoding

For more information about the CONSTRAINED UNPREDICTABLE behavior of this instruction, see Architectural Constraints on UNPREDICTABLE behaviors.

Assembler Symbols

Operation

if ConditionPassed() then EncodingSpecificOperations(); // Do nothing end;

Operational information

This instruction is a data-independent-time instruction as described in About the DIT bit.

2026-03_rel 2026-03-26 20:48:11