Consumption of Speculative Data Barrier is a memory barrier that controls speculative execution arising from data value prediction. For more information and details of the semantics, see Consumption of Speculative Data Barrier (CSDB).
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 |
| != 1111 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | (1) | (1) | (1) | (1) | (0) | (0) | (0) | (0) | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | |||
| cond | |||||||||||||||||||||||||||||||
if cond != '1110' then UNPREDICTABLE; // CSDB must be encoded with AL condition
If cond != '1110', then one of the following behaviors must occur:
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| 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 | 1 | 0 | 1 | 0 | 0 |
if InITBlock() then UNPREDICTABLE;
If InITBlock(), then one of the following behaviors must occur:
For more information about the constrained unpredictable behavior, see Architectural Constraints on UNPREDICTABLE behaviors.
if ConditionPassed() then EncodingSpecificOperations(); ConsumptionOfSpeculativeDataBarrier();
Internal version only: isa v01_31, pseudocode v2024-03_rel ; Build timestamp: 2024-03-25T10:05
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