HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens

                     BSR - Bit Scan Reverse  (386+ only)


       Usage:  BSR     dest,src
       Modifies flags: ZF


       Scans source operand for first bit set.  Sets ZF if a bit is found
       set and loads the destination with an index to first set bit.  Clears
       ZF is no bits are found set.  BSF scans forward across bit pattern
       (0-n) while BSR scans in reverse (n-0).


                                Clocks                 Size
       Operands         808x  286   386   486          Bytes

       reg,reg           -     -   10+3n  6-103          3
       reg,mem           -     -   10+3n  7-104         3-7
       reg32,reg32       -     -   10+3n  6-103         3-7
       reg32,mem32       -     -   10+3n  7-104         3-7


       - see Instruction Timing

Esc or Alt-X to exit bsr Home/PgUp/PgDn/End ←↑↓→