Editing JMP (x86 instruction) (section)

== Far Jumps ==

=== Real-Address or Virtual-8086 Mode ===

* The target address includes both:
** A '''segment selector''' (loaded into <code>CS</code>), and
** An '''offset''' (loaded into <code>EIP</code>).

The target can be specified:

# '''Directly''': Encoded as a pointer (<code>ptr16:16</code> or <code>ptr16:32</code>) in the instruction.
# '''Indirectly''': Stored in memory (<code>m16:16</code> or <code>m16:32</code>) and fetched by the instruction.

=== Protected Mode ===
In protected mode, far jumps can be used for:

# '''Switching Code Segments'''
#* A jump to a '''conforming''' or '''non-conforming code segment'''.
#* The <code>CS</code> register is updated with the target segment selector, and <code>EIP</code> is updated with the offset.
# '''Using a Call Gate'''
#* The target operand specifies a '''call gate descriptor''', which defines the segment and offset to jump to.
#* This approach allows indirect jumps and is preferred for transitions between '''16-bit''' and '''32-bit''' segments.
# '''Performing a Task Switch'''
#* The target specifies a '''task gate''' or directly references a '''TSS'''.
#* The task's segment selectors (code and stack) and the <code>EIP</code> are loaded from the TSS.

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