Speculation Barrier is a barrier that controls speculation. For more information and details of the semantics, see Speculation Barrier (SB).
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| 1 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 1 | (0) | (0) | (0) | (0) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| CRm | opc | ||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_SB) then UNDEFINED;