CFP

Control Flow Prediction Restriction by Context prevents control flow predictions that predict execution addresses based on information gathered from earlier execution within a particular execution context. Control flow predictions determined by the actions of code in the target execution context or contexts appearing in program order before the instruction cannot be used to exploitatively control speculative execution occurring after the instruction is complete and synchronized.

For more information, see CFP RCTX, Control Flow Prediction Restriction by Context.

This is an alias of SYS. This means:

System
(FEAT_SPECRES)

313029282726252423222120191817161514131211109876543210
110101010000101101110011100Rt
Lop1CRnCRmop2

CFP RCTX, <Xt>

is equivalent to

SYS #3, C7, C3, #4, <Xt>

and is always the preferred disassembly.

Assembler Symbols

<Xt>

Is the 64-bit name of the general-purpose source register, encoded in the "Rt" field.

Operation

The description of SYS gives the operational pseudocode for this instruction.


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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