* SHA (zpg),Y and SHA abs,Y (opcodes 93, 9F) are broken versions of SAX (zpg),Y and SAX abs,Y
* NOP zpg,X (opcodes D4, F4) are broken versions of CPY zpg,X and CPX zpg,X
* NOP abs,X (opcodes DC, FC) are broken versions of CPY abs,X and CPY CPX abs,X
* NOP # (opcodes 80, 82, 89) are the useless instructions STY #, STX #, STA #
* NOP # (opcodes C2, E2) are the useless instructions DEC #, INC #