AESD AES single round decryption AES single round decryption. This instruction is a data-independent-time instruction as described in About PSTATE.DIT. 0 1 0 0 1 1 1 0 0 0 1 0 1 0 0 0 0 1 0 1 1 0 AESD <Vd>.16B, <Vn>.16B if !IsFeatureImplemented(FEAT_AES) then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); <Vd> Is the name of the SIMD&FP source and destination register, encoded in the "Rd" field. <Vn> Is the name of the second SIMD&FP source register, encoded in the "Rn" field. AArch64_CheckFPAdvSIMDEnabled(); let operand1 : bits(128) = V{}(d); let operand2 : bits(128) = V{}(n); var result : bits(128) = operand1 XOR operand2; result = AESInvShiftRows(result); V{128}(d) = AESInvSubBytes(result); 2026-03-12 12:23:09 2025-09_rel_asl1