gdb/745: 16 bit real-mode for the i386

[ac131313 at redhat dot com]

>Number:         745
>Category:       gdb
>Synopsis:       16 bit real-mode for the i386
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Fri Sep 27 13:48:01 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     ac131313@redhat.com
>Release:        unknown-1.0
>Organization:
>Environment:

>Description:
See:
http://sources.redhat.com/ml/gdb-patches/2002-08/msg00995.html
- needs doco
- needs a testcase

--

Hello,

The attached modifies i386-tdep.c so that there is a ``set i386 real-mode'' command (doco to go).

When real-mode is enabled, GDB computes the ``20 bit'' ``stop address'' (aka PC but not to be confused with $pc ... :-) from both the $cs and $pc registers.  That way, core GDB sees a cannonical PC address that (regardless of $cs) will match a ``20 bit'' breakpoint address.

Thoughts?

I'm desperatly trying to come up with a test-case mind.  This is a rewrite of an old old patch (that hacked breakpoint.c) and the original testcase has been lost :-(

Andrew


>How-To-Repeat:

>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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