xpacd

Strip Pointer Authentication Code (Data)

XPACD <Xd>

Removes the PAC signature from a data pointer.

Pseudocode Operation

Xd ← StripPAC(Xd, DataPointer)

Example

XPACD x0

Encoding

Binary Layout

1

31

1

30

0

29

11010110

28:21

00001

20:16

01000

15:11

1

10

11111

9:5

Rd

4:0

 

Format Data Processing

Opcode 0xDAC147E0

Extension PAC (Security)

Operands

• Xd
  Ptr

Related

More in PAC (Security)

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0xDAC147E0	XPACD <Xd>		A64		1 | 1 | 0 | 11010110 | 00001 | 01000 | 1 | 11111 | Rd

Description

Strip Pointer Authentication Code. This instruction removes the pointer authentication code from an address. The address is in the specified general-purpose register for XPACI and XPACD, and is in LR for XPACLRI. The XPACD instruction is used for data addresses, and XPACI and XPACLRI are used for instruction addresses.

Operation

if IsFeatureImplemented(FEAT_PAuth) then
    X[d, 64] = Strip(X[d, 64], data);