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Intel 253666-024US User Manual

Page 579

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Vol. 2A 3-533

INSTRUCTION SET REFERENCE, A-M

LDS/LES/LFS/LGS/LSS—Load Far Pointer

#SS

If a memory operand effective address is outside the SS

segment limit.

#UD

If source operand is not a memory location.
If the LOCK prefix is used.

Virtual-8086 Mode Exceptions

#UD

If source operand is not a memory location.
If the LOCK prefix is used.

#GP(0)

If a memory operand effective address is outside the CS, DS,

ES, FS, or GS segment limit.

#SS(0)

If a memory operand effective address is outside the SS

segment limit.

#PF(fault-code)

If a page fault occurs.

#AC(0)

If alignment checking is enabled and an unaligned memory

reference is made.

Compatibility Mode Exceptions

Same exceptions as in protected mode.

64-Bit Mode Exceptions

#GP(0)

If the memory address is in a non-canonical form.
If a NULL selector is attempted to be loaded into the SS register

in compatibility mode.

If a NULL selector is attempted to be loaded into the SS register

in CPL3 and 64-bit mode.

If a NULL selector is attempted to be loaded into the SS register

in non-CPL3 and 64-bit mode where its RPL is not equal to CPL.

#GP(Selector)

If the FS, or GS register is being loaded with a non-NULL

segment selector and any of the following is true: the segment
selector index is not within descriptor table limits, the memory
address of the descriptor is non-canonical, the segment is
neither a data nor a readable code segment, or the segment is a
data or nonconforming-code segment and both RPL and CPL are
greater than DPL.

If the SS register is being loaded and any of the following is true:

the segment selector index is not within the descriptor table
limits, the memory address of the descriptor is non-canonical,
the segment selector RPL is not equal to CPL, the segment is a
nonwritable data segment, or DPL is not equal to CPL.

#SS(0)

If a memory operand effective address is non-canonical

#SS(Selector)

If the SS register is being loaded and the segment is marked not

present.