In this paper we first present two tagging mechanisms; the SCISM and IA-64; thereafter we describe the mapping of IA-64 ISA to a SCISM configuration without changing or reassigning the IA-64 instructions to preserve the original architectural properties. Under this limiting SCISM scenario, opcode reassignment will improve even more the SCISM performance, it is shown that SCISM tagging will significantly improve (between 21 and 29%) static code density. The results are based on analysis of various SPECINT2000 executables.