[Arm] Stack pointer setup thumb
Thu Mar 7 18:14:00 GMT 2019
On Thu, 7 Mar 2019 at 18:45, Nick Clifton <firstname.lastname@example.org> wrote:
> Hi Alex,
> > I hope you are have some memories on this fix :)
> Not really :-(
> > Is this still relevant ?
> The whole patch, or just part of it ?
That part below (with sp initialization)
> > The problem is that users complaining that it has different behavior
> > in ARM and Thumb modes for one Cortex-R core. And they do expected
> > that library will make some minimal initialization in both ISA
> > versions.
> Well to be honest I really do not remember what prompted this patch in
> the first place. So if you have a fix which makes the users happy and
> which does not break anything then I would say "go for it". :-)
> > Should we just remove this ?
> > +#ifdef __thumb2__
> > + /* XXX Fill in stack assignments for interrupt modes. */
> > +#else
> Sure - I would have no problems with that. The comment was more
> of a suggestion that someone needs to make sure that the stack
> pointer is set up before interrupts happen, but it does not have
> to be in this particular piece of code. Plus presumably this has
> already been done, or else many more people would be complaining
> about interrupts not working in Thumb mode.
Yep. Basic idea is to have sp initialization for exceptions as well.
Actually I already proposed a patch for this piece of code where I moved
initialuzation in weak subroutine. But I saved this ifdef there as well. I
will update patch then :)
Thsnk you Nick !
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