let t : integer{} = UInt(Rt); let n : integer{} = UInt(Rn); let regsize : integer{} = 64 >> UInt(opc[0]); let nontemporal : boolean = FALSE; let tagchecked : boolean = wback || n != 31; var c : Constraint; var wb_unknown : boolean = FALSE; if wback && n == t && n != 31 then c = ConstrainUnpredictable(Unpredictable_WBOVERLAPLD); assert c IN {Constraint_WBSUPPRESS, Constraint_UNKNOWN, Constraint_UNDEF, Constraint_NOP}; case c of when Constraint_WBSUPPRESS => wback = FALSE; // Writeback is suppressed when Constraint_UNKNOWN => wb_unknown = TRUE; // Writeback is UNKNOWN when Constraint_UNDEF => EndOfDecode(Decode_UNDEF); when Constraint_NOP => EndOfDecode(Decode_NOP); end; end;

var address : bits(64); let privileged : boolean = PSTATE.EL != EL0; let accdesc : AccessDescriptor = CreateAccDescGPR(MemOp_LOAD, nontemporal, privileged, tagchecked, t); if n == 31 then CheckSPAlignment(); address = SP{64}(); else address = X{64}(n); end; if !postindex then address = AddressAdd(address, offset, accdesc); end; let data : bits(16) = Mem{16}(address, accdesc); X{regsize}(t) = SignExtend{regsize}(data); if wback then if wb_unknown then address = ARBITRARY : bits(64); elsif postindex then address = AddressAdd(address, offset, accdesc); end; if n == 31 then SP{64}() = address; else X{64}(n) = address; end; end;