pacga

Pointer Authentication Code Generic Address

PACGA <Xd>, <Xn>, <Xm>

Computes a pointer authentication code for an address and modifier.

Pseudocode Operation

pac ← ComputePAC(Xn, Xm, PAC_key_generic)
Xd ← SignExtend(pac, 64)

Example

PACGA x0, x1, x2

Encoding

Binary Layout

1

31

0

30

0

29

11010110

28:21

Rm

20:16

001100

15:10

Rn

9:5

Rd

4:0

 

Format Data Processing

Opcode 0x9AC03000

Extension PAC (Security)

Operands

• Xd
  Destination 64-bit integer register
• Xn
  Address
• Xm
  Modifier

Related

More in PAC (Security)

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0x9AC03000	PACGA <Xd>, <Xn>, <Xm|SP>		A64		1 | 0 | 0 | 11010110 | Rm | 001100 | Rn | Rd

Description

Pointer Authentication Code, using Generic key. This instruction computes the pointer authentication code for a 64-bit value in the first source register, using a modifier in the second source register, and the Generic key. The computed pointer authentication code is written to the most significant 32 bits of the destination register, and the least significant 32 bits of the destination register are set to zero.

Operation

if source_is_sp then
    X[d, 64] = AddPACGA(X[n, 64], SP[]);
else
    X[d, 64] = AddPACGA(X[n, 64], X[m, 64]);