Exception Return, with pointer authentication.
Supported in ARMv8.3.
Exception Return, with pointer authentication. This instruction authenticates the address in ELR, using SP as the modifier and the specified key, the PE restores PSTATE from the SPSR for the current Exception level, and branches to the authenticated address.
Key A is used for
ERETAA, and key B is used for
If the authentication passes, the PE continues execution at the target of the branch. If the authentication fails, a Translation fault is generated.
The authenticated address is not written back to ELR.
The PE checks the SPSR for the current Exception level for an illegal return event. See Illegal return events from AArch64 state in the ARMv8-A Architecture Reference Manual.
ERET is undefined at EL0.