Re: how to port insight to a new target

[Keith Seitz <keiths at redhat dot com>]

On 05/06/2010 03:33 AM, vincent chen wrote:

> I have ported GDB by adding a new target in sim,and the gdb appears to
> run properly on simulator.

You've already got most of the work done, then.

> I've no idea about which start by,it's better to show me the approach
> on porting insight,

Unfortunately, there is no documentation on how to do this, so you're 
just gong to have to tackle the problems one-by-one. Honestly, this 
sholudn't take very long at all.

The most important thing to do is add your target to the target database 
in TargetSelection::init_target_db 
(src/gdb/gdbtk/library/targetselection.itb). If your -tdep file is 
written correctly, that should be all that is necessary.

However, there are usually some minor problems. One of the most common 
is that insight doesn't notice that the target is "running" (the toolbar 
buttons Run/Stop, Step, Next, etc are all disabled/grayed out). This 
happens because the test "gdb_target_has_execution" fails (in Tcl). This 
command is implemented in src/gdb/gdbtk/generic/gdbtk-cmds.c in the 
function "gdb_target_has_execution_command". remote.c should contain 
bits of this that will demonstrate how to pass this test.

The only other thing that usually crops up is that while the target is 
running, the GUI locks up. This is because the (deprecated_)ui_loop_hook 
isn't being called to allow the Tcl event loop to run. [A sad 
consequence of the design of gdb at the time.] Make sure this function 
gets called at reasonable intervals in your simulator. Other simulators 
in the repository should already do this.

Of course, if there are any other problems, just send them to the list, 
and I'll try to help you through them.

Good luck,
Keith