Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

## AUTDA, AUTDZA

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

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

The modifier is:

- In the general-purpose register or stack pointer that is specified by <Xn|SP> for AUTDA.
- The value zero, for AUTDZA.

If the authentication passes, the upper bits of the address are restored to enable subsequent use of the address. If the authentication fails, the upper bits are corrupted and any subsequent use of the address results in a Translation fault.

### 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 | 0 | Rn | Rd

#### AUTDA (Z == 0)

AUTDA <Xd>, <Xn|SP>

#### AUTDZA (Z == 1 && Rn == 11111)

AUTDZA <Xd>

boolean source_is_sp = FALSE; integer d = UInt(Rd); integer n = UInt(Rn); if !HavePACExt() then UNDEFINED; if Z == '0' then // AUTDA if n == 31 then source_is_sp = TRUE; else // AUTDZA 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 HavePACExt() then if source_is_sp then X[d, 64] = AuthDA(X[d, 64], SP[], FALSE); else X[d, 64] = AuthDA(X[d, 64], X[n, 64], FALSE);

Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

Internal version only: isa v33.53, AdvSIMD v29.11, pseudocode v2022-09_rel, sve v2022-09_rel ; Build timestamp: 2022-09-30T16:37

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