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 1111011w    mod,100,r/m      disp (0, 1, or 2)
─────────────────┬────────────────────────┬─────────────────────────────────
 MUL  reg        │ mul   bx               │ 88/86 b=70-77,w=118-133
                 │ mul   dl               │   286 b=13,w=21
                 │                        │   386 b=9-14,w=9-22,d=9-38
                 │                        │   486 b=13-18,w=13-26,d=13-42
─────────────────┼────────────────────────┼─────────────────────────────────
 MUL  mem        │ mul   factor           │ 88/86 (b=76-83,w=124-139)+EA*
                 │ mul   WORD PTR [bx]    │   286 b=16,w=24
                 │                        │   386 b=12-17,w=12-25,d=12-41
                 │                        │   486 b=13-18,w=13-26,d=13-42
─────────────────┴────────────────────────┴─────────────────────────────────
  * Word memory operands on the 8088 take (128-143)+EA clocks.
 
    The 80386/486 has an early-out multiplication algorithm. Therefore,
    multiplying an 8-bit or 16-bit value in EAX takes the same time as
    multiplying the value in AL or AX.
                                    -♦-