Exception return
This instruction restores PSTATE from the SPSR, and branches to the address held in the ELR.
The SPSR is checked for the current Exception level for an illegal return event. See Illegal exception returns from AArch64 state.
ERET is UNDEFINED at EL0.
| 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 |
| 1 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 |
| opc | op2 | A | M | Rn | op4 | ||||||||||||||||||||||||||
constant boolean pac = FALSE; constant boolean use_key_a = TRUE;
if PSTATE.EL == EL0 then UNDEFINED; AArch64.CheckForERetTrap(pac, use_key_a); constant bits(64) target = ELR_ELx[]; AArch64.ExceptionReturn(target, SPSR_ELx[]);
Internal version only: aarchmrs v2024-12_rel, pseudocode v2024-12_rel ; Build timestamp: 2024-12-15T22:18
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