Clear Branch History clears the branch history for the current context to the extent that branch history information created before the CLRBHB instruction cannot be used by code before the CLRBHB instruction to exploitatively control the execution of any indirect branches in code in the current context that appear in program order after the instruction.
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 | 1 | 0 | |||
| cond | |||||||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_CLRBHB) then EndOfInstruction(); // Instruction executes as NOP
| 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 | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 |
if !IsFeatureImplemented(FEAT_CLRBHB) then EndOfInstruction(); // Instruction executes as NOP
Internal version only: isa v01_31, pseudocode v2024-03_rel ; Build timestamp: 2024-03-25T10:05
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