Assembly Language Help (alang.hlp) (Table of Contents; Topic list)
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REP Instruction
 Summary Key Example                    Up Contents Index Back
────────────────────────────────────────────────────────────────────────────
 
 11110011    1010010w
─────────────────────┬─────────────────────────┬────────────────────────────
 REP MOVS dest,src   │ rep   movs source,dest  │ 88/86 9+17n (W88=9+25n)
 REP MOVSB [dest,src]│ rep   movsw             │   286 5+4n
 REP MOVSW [dest,src]│                         │   386 7+4n
 REP MOVSD [dest,src]│                         │   486 12+3n
─────────────────────┴─────────────────────────┴────────────────────────────
 
 11110011    1010101w
─────────────────────┬─────────────────────────┬────────────────────────────
 REP STOS dest       │ rep   stosb             │ 88/86 9+10n (W88=9+14n)
 REP STOSB [dest]    │ rep   stos dest         │   286 4+3n
 REP STOSW [dest]    │                         │   386 5+5n
 REP STOSD [dest]    │                         │   486 7+4n
─────────────────────┴─────────────────────────┴────────────────────────────
 
 11110010    1010110w
─────────────────────┬─────────────────────────┬────────────────────────────
 REP LODS dest       │ rep   lodsb             │ 88/86 ──
 REP LODSB [dest]    │ rep   lods dest         │   286 ──
 REP LODSW [dest]    │                         │   386 ──
 REP LODSD [dest]    │                         │   486 7+4n
─────────────────────┴─────────────────────────┴────────────────────────────
 
 11110011    0110110w
─────────────────────┬─────────────────────────┬────────────────────────────
 REP INS  dest,DX    │ rep   insb              │ 88/86 ──
 REP INSB [dest,DX]  │ rep   ins dest,dx       │   286 5+4n
 REP INSW [dest,DX]  │                         │   386 13+6n,pm=(7,27)+6n*
 REP INSD [dest,DX]  │                         │   486 16+8n,pm=(10,30)+8n*
─────────────────────┴─────────────────────────┴────────────────────────────
 
 11110011    0110111w
─────────────────────┬─────────────────────────┬────────────────────────────
 REP OUTS DX,src     │ rep   outs dx,source    │ 88/86 ──
 REP OUTSB [src]     │ rep   outsw             │   286 5+4n
 REP OUTSW [src]     │                         │   386 12+5n,pm=(6,26)+5n*
 REP OUTSD [src]     │                         │   486 17+5n,pm=(11,31)+5n*
─────────────────────┴─────────────────────────┴────────────────────────────
  * First protected-mode timing: CPL <= IOPL. Second timing: CPL > IOPL.
 
    5 if n = 0, 13 if n = 1.
 
    5 if n = 0.
                                    -♦-