SB -- AArch32

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SB -- AArch32

SB

Speculation Barrier is a barrier that controls speculation. For more information and details of the semantics, see Speculation Barrier (SB).

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

A1
(FEAT_SB)

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
1	1	1	1	0	1	0	1	0	1	1	1	(1)	(1)	(1)	(1)	(1)	(1)	(1)	(1)	(0)	(0)	(0)	(0)	0	1	1	1	(0)	(0)	(0)	(0)
																								opcode				option

Encoding

SB{<q>}

Decode for this encoding

// No additional decoding required

T1
(FEAT_SB)

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	1	(1)	(1)	(1)	(1)	1	0	(0)	0	(1)	(1)	(1)	(1)	0	1	1	1	(0)	(0)	(0)	(0)
																								opc				option

Encoding

SB{<q>}

Decode for this encoding

if InITBlock() then UnpredictableProcedure(); end;

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

Assembler Symbols

<q>	See Standard assembler syntax fields.

Operation

if ConditionPassed() then EncodingSpecificOperations(); SpeculationBarrier(); end;

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

SB

A1(FEAT_SB)

Encoding

Decode for this encoding

T1(FEAT_SB)

Encoding

Decode for this encoding

Assembler Symbols

Operation

A1
(FEAT_SB)

T1
(FEAT_SB)