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SYS

System instruction

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

This instruction is used by the aliases APAS, AT, BRB, CFP, COSP, CPP, DC, DVP, GCSPOPCX, GCSPOPX, GCSPUSHM, GCSPUSHX, GCSSS1, IC, TLBI, and TRCIT.

313029282726252423222120191817161514131211109876543210
1101010100001op1CRnCRmop2Rt
L

Encoding

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

Decode for this encoding

constant integer t = UInt(Rt); constant bits(1) sys_L = L; constant bits(2) sys_op0 = '01'; constant bits(3) sys_op1 = op1; constant bits(3) sys_op2 = op2; constant bits(4) sys_crn = CRn; constant bits(4) sys_crm = CRm;

Assembler Symbols

<op1>

Is a 3-bit unsigned immediate, in the range 0 to 7, encoded in the "op1" field.

<Cn>

Is a name 'Cn', with 'n' in the range 0 to 15, encoded in the "CRn" field.

<Cm>

Is a name 'Cm', with 'm' in the range 0 to 15, encoded in the "CRm" field.

<op2>

Is a 3-bit unsigned immediate, in the range 0 to 7, encoded in the "op2" field.

<Xt>

Is the 64-bit name of the optional general-purpose source register, defaulting to '11111', encoded in the "Rt" field.

Alias Conditions

AliasIs preferred when
APASop1 == '110' && CRn == '0111' && CRm == '0000' && op2 == '000'
ATCRn == '0111' && CRm IN {'100x'} && SysOp(op1, '0111', CRm, op2) == Sys_AT
BRBop1 == '001' && CRn == '0111' && CRm == '0010' && SysOp('001', '0111', '0010', op2) == Sys_BRB
CFPop1 == '011' && CRn == '0111' && CRm == '0011' && op2 == '100'
COSPop1 == '011' && CRn == '0111' && CRm == '0011' && op2 == '110'
CPPop1 == '011' && CRn == '0111' && CRm == '0011' && op2 == '111'
DCCRn == '0111' && SysOp(op1, '0111', CRm, op2) == Sys_DC
DVPop1 == '011' && CRn == '0111' && CRm == '0011' && op2 == '101'
GCSPOPCXop1 == '000' && CRn == '0111' && CRm == '0111' && op2 == '101'
GCSPOPXop1 == '000' && CRn == '0111' && CRm == '0111' && op2 == '110'
GCSPUSHMop1 == '011' && CRn == '0111' && CRm == '0111' && op2 == '000'
GCSPUSHXop1 == '000' && CRn == '0111' && CRm == '0111' && op2 == '100'
GCSSS1op1 == '011' && CRn == '0111' && CRm == '0111' && op2 == '010'
ICCRn == '0111' && SysOp(op1, '0111', CRm, op2) == Sys_IC
TLBICRn IN {'100x'} && SysOp(op1, CRn, CRm, op2) == Sys_TLBI
TRCITop1 == '011' && CRn == '0111' && CRm == '0010' && op2 == '111'

Operation

AArch64.CheckSystemAccess(sys_op0, sys_op1, sys_crn, sys_crm, sys_op2, t, sys_L); AArch64.SysInstr(sys_op0, sys_op1, sys_crn, sys_crm, sys_op2, t);