Instructions by mnemonic mnemonic:
opcode: processor:  remark & remedy:

AAA            i80286 & i80386 & i80486

CMPS                    i80286
CMPXCHG                 i80486
FINIT
FSTSW
FSTCW


INS                     i80286 &
                        i80386 &
                        i80486

INVD                    i80486



MOV to SS        n/a    early 8088  Some early 8088 would not properly
                                    disable interrupts after a move to
                                    the SS register. Workaround would
                                    be to explicitly clear the
                                    interrupts, update SS and SP and
                                    then re-enable the interrupts.
                                    Typically this would occur in a
                                    situation where one would relocate
                                    a stack in memory, more than 64Kb
                                    from the original one, updating
                                    both SS and SP like in:
                                      MOV SS,AX  ; would disable
                                                   interrupts
                                                   automatically during
                                                   this and next
                                                   instruction.
                                      MOV SP,DX  ; interrupts disabled
                                      ...        ; interrupts enabled.


multiple prefixes
with REPx               8088 & 8086 They would not properly restart at
                                    the first prefix byte after an
                                    interrupt. when more than one
                                    prefix is used. e.g. LOCK REP MOVSW
                                    CS:[bx]. A workaround is to test
                                    after the instruction for CX==0,
                                    here: LOCK REP MOVSW CS:[BX] OR
                                    CX,CX JNZ here because of the CS
                                    override, the REP and LOCK prefixes
                                    would not be recognised to be part
                                    of the instruction and the REP MOVSW
                                    would be aborted. This also seems to
                                    be the case for a REP MOVSW CS:[BX]
                                    Note that this also implies that
                                    REPZ, REPNZ are affected in SCASW
                                    for instance.

                                                                                                                
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