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LAR             Load Access Rights                   Flags: O D I T S Z A P C
                                                            - - - - - * - - -
LAR destination,source                               CPU: 286+ p

        Logic   dest16 . (bits 32-47 of descriptor) AND FF00h
             or dest32 . (bits 32-63 of descriptor) AND 00F0FF00h
                if error
                   ZF . 0
                else
                   ZF . 1
                endif

    This instruction reads a masked form of a segment descriptor and
    returns the following bits to the destination register:

                Bits    Contents
    dest32   |  23      Granularity
             |  22      Default Operation Size
             |  20      Programmer-available
             |  15      Segment Present        |
             |  14-13   DPL                    |
             |  12      Segment                |  dest16
             |  11-9    Type                   |
             |  8       Accessed               |
             |  (Other bits zero)              |


    The descriptor specified by the selector in the first operand must
    be within the descriptor table limits, have a valid type field,
    and be accessible at both CPL (Current Privilege Level) and RPL
    (Requestor's Privilege Level) of the selector in the second
    operand compared to DPL (Descriptor Privilege Level). If so, ZF is
    set to 1 and the segment attributes are loaded to the first
    operand. If not, ZF is set to zero, and the first operand is
    unmodified (due to privilege or GDT or LDT limits).

    If the 32-bit operand size is specified, the entire 32-bit value
    is loaded into the 32-bit destination. If the 16-bit operand size
    is specified, the lower 16 bits of this value are stored in the
    16-bit destination register.

    The following special-segment and gate-descriptor types are valid
    for LAR: 1,2,3,4,5,6,7,9,B,C,E,F. All application code and data
    segment descriptors are valid.


        Example:        sub     eax,eax
                        mov     ax,cs
                        mov     ebx,eax
                        lar     eax,ebx


    Opcode      Format
    0F 02 /r    LAR  r16,r/m16
    0F 02 /r    LAR  r32,r/m32


    Length and timing
    Operands    Bytes   8088    186     286     386     486     Pentium
    r16, r16     3                      14      15      11       8   NP
    r32, r32     3                       -      15      11       8   NP
    r16, m16     3                      16      16      11       8   NP
    r32, m32     3                       -      16      11       8   NP