integer d = UInt(Rd);
			integer n = UInt(Rn);
			integer size;
			case Q:imm5 of
			    when 'xxxxx1' size = 0;     // SMOV [WX]d, Vn.B
			    when 'xxxx10' size = 1;     // SMOV [WX]d, Vn.H
			    when '1xx100' size = 2;     // SMOV Xd, Vn.S
			    otherwise     UNDEFINED;
			integer idxdsize = if imm5<4> == '1' then 128 else 64;
			integer index = UInt(imm5<4:size+1>);
			integer esize = 8 << size;
			integer datasize = if Q == '1' then 64 else 32;