Index

AUTDB, AUTDZB

Authenticate Data address, using key B. This instruction authenticates a data address, using a modifier and key B.

The address is in the general-purpose register that is specified by <Xd>.

The modifier is:

If the authentication passes, the upper bits of the address are restored to enable subsequent use of the address. For information on behavior if the authentication fails, see Faulting on pointer authentication.

Integer
(FEAT_PAuth)

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 1 0 1 0 1 1 0 0 0 0 0 1 0 0 Z 1 1 1 Rn Rd

AUTDB (Z == 0)

AUTDB <Xd>, <Xn|SP>

AUTDZB (Z == 1 && Rn == 11111)

AUTDZB <Xd>

boolean source_is_sp = FALSE;
integer d = UInt(Rd);
integer n = UInt(Rn);

if !IsFeatureImplemented(FEAT_PAuth) then
    UNDEFINED;

if Z == '0' then // AUTDB
    if n == 31 then source_is_sp = TRUE;
else // AUTDZB
    if n != 31 then UNDEFINED;

Assembler Symbols

<Xd>

Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.
<Xn|SP>

Is the 64-bit name of the general-purpose source register or stack pointer, encoded in the "Rn" field.

Operation

if IsFeatureImplemented(FEAT_PAuth) then
    if source_is_sp then
        X[d, 64] = AuthDB(X[d, 64], SP[], FALSE);
    else
        X[d, 64] = AuthDB(X[d, 64], X[n, 64], FALSE);