Data Synchronization Barrier is a memory barrier that ensures the completion of memory accesses, see Data Synchronization Barrier (DSB).
It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .
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 | 0 | 0 | option |
// No additional decoding required
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 | 0 | 0 | option |
// No additional decoding required
For more information about the constrained unpredictable behavior, see Architectural Constraints on UNPREDICTABLE behaviors.
<c> |
For encoding A1: see Standard assembler syntax fields. Must be AL or omitted. |
For encoding T1: see Standard assembler syntax fields. |
<q> |
if ConditionPassed() then EncodingSpecificOperations(); case option of when '0001' domain = MBReqDomain_OuterShareable; types = MBReqTypes_Reads; when '0010' domain = MBReqDomain_OuterShareable; types = MBReqTypes_Writes; when '0011' domain = MBReqDomain_OuterShareable; types = MBReqTypes_All; when '0101' domain = MBReqDomain_Nonshareable; types = MBReqTypes_Reads; when '0110' domain = MBReqDomain_Nonshareable; types = MBReqTypes_Writes; when '0111' domain = MBReqDomain_Nonshareable; types = MBReqTypes_All; when '1001' domain = MBReqDomain_InnerShareable; types = MBReqTypes_Reads; when '1010' domain = MBReqDomain_InnerShareable; types = MBReqTypes_Writes; when '1011' domain = MBReqDomain_InnerShareable; types = MBReqTypes_All; when '1101' domain = MBReqDomain_FullSystem; types = MBReqTypes_Reads; when '1110' domain = MBReqDomain_FullSystem; types = MBReqTypes_Writes; otherwise domain = MBReqDomain_FullSystem; types = MBReqTypes_All; if HaveEL(EL2) && !IsSecure() && PSTATE.EL IN {EL0,EL1} then if HCR.BSU == '11' then domain = MBReqDomain_FullSystem; if HCR.BSU == '10' && domain != MBReqDomain_FullSystem then domain = MBReqDomain_OuterShareable; if HCR.BSU == '01' && domain == MBReqDomain_Nonshareable then domain = MBReqDomain_InnerShareable; DataSynchronizationBarrier(domain, types);
Internal version only: isa v00_79, pseudocode v34.2 ; Build timestamp: 2017-12-19T15:42
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