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MRS

Move Special register to general-purpose register moves the value of the APSR, CPSR, or SPSR_<current_mode> into a general-purpose register.

Arm recommends the APSR form when only the N, Z, C, V, Q, and GE[3:0] bits are being written. For more information, see APSR.

An MRS that accesses the SPSRs is UNPREDICTABLE if executed in User mode or System mode.

An MRS that is executed in User mode and accesses the CPSR returns an UNKNOWN value for the CPSR.{E, A, I, F, M} fields.

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .

A1

Decode for this encoding

let d : integer = UInt(Rd); let read_spsr : boolean = (R == '1'); if d == 15 then UnpredictableProcedure(); end;

T1

Decode for this encoding

let d : integer = UInt(Rd); let read_spsr : boolean = (R == '1'); // Armv8-A removes UNPREDICTABLE for R13 if d == 15 then UnpredictableProcedure(); end;

Assembler Symbols