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

## PACDA, PACDZA

Pointer Authentication Code for Data address, using key A. This instruction computes and inserts a pointer authentication code for 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 PACDA.
- The value zero, for PACDZA.

### 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 | 0 | 1 | 0 | Rn | Rd

#### PACDA (Z == 0)

PACDA <Xd>, <Xn|SP>

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

PACDZA <Xd>

boolean source_is_sp = FALSE; integer d = UInt(Rd); integer n = UInt(Rn); if !IsFeatureImplemented(FEAT_PAuth) then UNDEFINED; if Z == '0' then // PACDA if n == 31 then source_is_sp = TRUE; else // PACDZA 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 source_is_sp then X[d, 64] = AddPACDA(X[d, 64], SP[]); else X[d, 64] = AddPACDA(X[d, 64], X[n, 64]);

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

Internal version only: isa v33.74, AdvSIMD v29.23, pseudocode v2023-09_rel, sve v2023-09_rc3 ; Build timestamp: 2023-09-27T17:06

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