MSR (immediate)

Move immediate value to special register

This instruction moves an immediate value to selected bits of the PSTATE. For more information, see Process state, PSTATE.

The bits that can be written by this instruction are:

• PSTATE.D, PSTATE.A, PSTATE.I, PSTATE.F, and PSTATE.SP.
• If FEAT_SSBS is implemented, PSTATE.SSBS.
• If FEAT_PAN is implemented, PSTATE.PAN.
• If FEAT_UAO is implemented, PSTATE.UAO.
• If FEAT_DIT is implemented, PSTATE.DIT.
• If FEAT_MTE is implemented, PSTATE.TCO.
• If FEAT_NMI is implemented, PSTATE.ALLINT.
• If FEAT_SME is implemented, PSTATE.SM and PSTATE.ZA.
• If FEAT_EBEP is implemented, PSTATE.PM.

If FEAT_MTE is implemented and FEAT_MTE2 is not implemented, it is IMPLEMENTATION DEFINED whether writes to PSTATE.TCO by this instruction are ignored.

This instruction is used by the aliases SMSTART, and SMSTOP.

Decode for this encoding

if op1 == '000' && op2 == '000' then See("CFINV"); end; if op1 == '000' && op2 == '001' then See("XAFLAG"); end; if op1 == '000' && op2 == '010' then See("AXFLAG"); end; var min_EL : bits(2); var need_secure : boolean = FALSE; case op1 of when '00x' => min_EL = EL1; when '010' => min_EL = EL1; when '011' => min_EL = EL0; when '100' => min_EL = EL2; when '101' => if !IsFeatureImplemented(FEAT_VHE) then EndOfDecode(Decode_UNDEF); end; min_EL = EL2; when '110' => min_EL = EL3; when '111' => min_EL = EL1; need_secure = TRUE; end; let operand : bits(4) = CRm; var field : PSTATEField; case op1::op2 of when '000 011' => if !IsFeatureImplemented(FEAT_UAO) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_UAO; when '000 100' => if !IsFeatureImplemented(FEAT_PAN) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_PAN; when '000 101' => field = PSTATEField_SP; when '001 000' => case CRm of when '000x' => if !IsFeatureImplemented(FEAT_NMI) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_ALLINT; when '001x' => if !IsFeatureImplemented(FEAT_EBEP) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_PM; otherwise => EndOfDecode(Decode_UNDEF); end; when '011 010' => if !IsFeatureImplemented(FEAT_DIT) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_DIT; when '011 011' => case CRm of when '001x' => if !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_SVCRSM; when '010x' => if !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_SVCRZA; when '011x' => if !IsFeatureImplemented(FEAT_SME) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_SVCRSMZA; otherwise => EndOfDecode(Decode_UNDEF); end; when '011 100' => if !IsFeatureImplemented(FEAT_MTE) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_TCO; when '011 110' => field = PSTATEField_DAIFSet; when '011 111' => field = PSTATEField_DAIFClr; when '011 001' => if !IsFeatureImplemented(FEAT_SSBS) then EndOfDecode(Decode_UNDEF); end; field = PSTATEField_SSBS; otherwise => EndOfDecode(Decode_UNDEF); end;