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  Title:    Rotate                                Flags: O D I T S Z A P C
                                                         ═════════════════
  Syntax:   RCL dest,count                               ±               ±
            ROL dest,count
            RCR dest,count
            ROR dest,count
 
  See also: SHL, SHLD
 
  Description:
 
     Rotates the bits in the destination operand the number of times
     specified in the source operand. RCL and ROL rotate the bits left;
     RCR and ROR rotate right.
 
     ROL and ROR rotate the number of bits in the operand. For each
     rotation, the leftmost or rightmost bit is copied to the carry
     flag as well as rotated.
 
     RCL and RCR rotate through the carry flag. The carry flag becomes
     an extension of the operand so that a 9-bit rotation is done for
     8-bit operands, or a 17-bit rotation for 16-bit operands.
 
     On the 8088 and 8086, the source operand can be either CL or 1.
     On the 80186-80486, the source operand can be CL or an 8-bit
     constant. On the 80186-80486, rotate counts larger than 31 are
     masked off, but on the 8088 and 8086, larger rotate counts can be
     performed despite the inefficiency involved.
 
     The overflow flag is modified only by single-bit variations of
     the instruction; for multiple-bit variations, it is undefined.
                                    -♦-