// in the original obj/i386, and it would encode
				// (using a valid, shorter form) as 3c 00 if we enabled
				// the call to bytereg here.
				if ctxt.Arch.Family == sys.AMD64 {
					bytereg(&p.From, &p.Ft)
					bytereg(&p.To, &p.Tt)
				}

			case P32: // 32 bit but illegal if 64-bit mode
				if ctxt.Arch.Family == sys.AMD64 {