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

## PACIB, PACIB1716, PACIBSP, PACIBZ, PACIZB

Pointer Authentication Code for Instruction address, using key B. This instruction computes and inserts a pointer authentication code for an instruction address, using a modifier and key B.

The address is:

- In the general-purpose register that is specified by <Xd> for PACIB and PACIZB.
- In X17, for PACIB1716.
- In X30, for PACIBSP and PACIBZ.

The modifier is:

- In the general-purpose register or stack pointer that is specified by <Xn|SP> for PACIB.
- The value zero, for PACIZB and PACIBZ.
- In X16, for PACIB1716.
- In SP, for PACIBSP.

It has encodings from 2 classes: Integer and System

### 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 | 0 | 1 | Rn | Rd

#### PACIB (Z == 0)

PACIB <Xd>, <Xn|SP>

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

PACIZB <Xd>

boolean source_is_sp = FALSE; integer d = UInt(Rd); integer n = UInt(Rn); if !HavePACExt() then UNDEFINED; if Z == '0' then // PACIB if n == 31 then source_is_sp = TRUE; else // PACIZB if n != 31 then UNDEFINED;

### System
(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 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | x | 1 | 0 | 1 | x | 1 | 1 | 1 | 1 | 1
|  |  |  |  | CRm | op2 |

#### PACIB1716 (CRm == 0001 && op2 == 010)

PACIB1716

#### PACIBSP (CRm == 0011 && op2 == 011)

PACIBSP

#### PACIBZ (CRm == 0011 && op2 == 010)

PACIBZ

integer d; integer n; boolean source_is_sp = FALSE; case CRm:op2 of when '0011 010' // PACIBZ d = 30; n = 31; when '0011 011' // PACIBSP d = 30; source_is_sp = TRUE; if HaveBTIExt() then // Check for branch target compatibility between PSTATE.BTYPE // and implicit branch target of PACIBSP instruction. SetBTypeCompatible(BTypeCompatible_PACIXSP()); when '0001 010' // PACIB1716 d = 17; n = 16; when '0001 000' SEE "PACIA"; when '0001 100' SEE "AUTIA"; when '0001 110' SEE "AUTIB"; when '0011 00x' SEE "PACIA"; when '0011 10x' SEE "AUTIA"; when '0011 11x' SEE "AUTIB"; when '0000 111' SEE "XPACLRI"; otherwise SEE "HINT";

### 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] = AddPACIB(X[d, 64], SP[]); else X[d, 64] = AddPACIB(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 v33.53, AdvSIMD v29.11, pseudocode v2022-09_rel, sve v2022-09_rel ; Build timestamp: 2022-09-30T16:37

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