Power Programmierung/Power-Programmierung (Tewi)(1994).iso/magazine/pctchnqs/1990/number5/tp6shift.pas

Pascal/Delphi Source File | 1990-10-19 | 609b | 15 lines

FUNCTION ShiftDWordRight(Target : LongInt;
                         ShiftBy : Integer) : LongInt;
                         ASSEMBLER;

ASM
    MOV DX, Target+2.WORD  { Move high order word into DX }
    MOV AX, Target.WORD    { Move low-order word into AX  }
    MOV CX, ShiftBy        { Move shift count into CX     }
    CLC                    { Clear the carry flag }
  @Shift:                  { Local label! }
    SHR DX,1               { Shift DX rightward }
    RCR AX,1               { Shift AX rightward with carry  }
    LOOP @Shift            { Loop back to @Shift if CX <> 0 }
END;