DBG -- AArch32

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DBG -- AArch32

DBG

DBG executes as a NOP. Arm deprecates any use of the DBG instruction.

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

A1

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)	1	1	1	1	option
cond									R			imm4

Encoding

DBG{<c>}{<q>} #<option>

Decode for this encoding

// DBG executes as a NOP. The 'option' field is ignored

T1

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	1	1	1	1	option
																								hint

Encoding

DBG{<c>}{<q>} #<option>

Decode for this encoding

// DBG executes as a NOP. The 'option' field is ignored

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

Assembler Symbols

<c>	See Standard assembler syntax fields.

<q>	See Standard assembler syntax fields.

Is a 4-bit unsigned immediate, in the range 0 to 15, encoded in the "option" field.

Operation

if ConditionPassed() then EncodingSpecificOperations(); end;

2025-09_rel_asl1 2026-03-12 12:57:38