Function:

LAR Loads the Access rights of a descriptor in the Global Descriptor Table,
whose selector is reg/mem into reg1. When successful, ZF=1, otherwise ZF=0.

Some 386es allow access to selector 0 in the GDT leaving ZF=1.
Normally this should not be possible and produce the condition ZF=0.

Workaround would be to create an entry 0 in the GDT that consists of only
zeroes. This will cause access with a selector of 0 to fail and
produce ZF=0.

A data breakpoint set to the mem16 operand of LAR can be missed on some
386es if the segment with the selector at mem16 is not accessible.
(see also <debugging>)




286-LOADALL / 386-LOADALL
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