sys

System Instruction

SYS #<op1>, Cn, Cm, #<op2> {, <Xt>}

Executes a system instruction (cache/TLB maintenance).

Pseudocode Operation

IMPLEMENTATION_DEFINED system operation based on (op1, Cn, Cm, op2); if Xt is present then Xt ← system_register_value or system_register_value ← Xt

Example

SYS #op1, Cn, Cm, #op2

Encoding

Binary Layout

1101010100

31:22

0

21

01

20:19

op1

18:16

CRn

15:12

CRm

11:8

op2

7:5

Rt

4:0

 

Format System

Opcode 0xD5080000

Extension System

Operands

• op1
  Op1
• Cn
  CRn
• Cm
  CRm
• op2
  Op2

Related

More in System

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0xD5080000	SYS #<op1>, <Cn>, <Cm>, #<op2>{, <Xt>}		A64		1101010100 | 0 | 01 | op1 | CRn | CRm | op2 | Rt

Description

System instruction. For more information, see Op0 equals 0b01, cache maintenance, TLB maintenance, and address translation instructions for the encodings of System instructions.

Operation

AArch64.SysInstr(1, sys_op1, sys_crn, sys_crm, sys_op2, t);