[RFC PATCH v1] arm: lib: add __gnu_thumb1_case_si

[Pali Rohár]

On Saturday 01 April 2023 15:17:59 Tony Dinh wrote:
> Hi Francis,
> 
> On Sat, Apr 1, 2023 at 2:55 PM Francis Laniel
> <francis.laniel at amarulasolutions.com> wrote:
> >
> > The assembly for __gnu_thumb1_case_si was taken from upstream gcc and adapted
> > as width suffix was removed for the add instruction [1].
> >
> > Signed-off-by: Francis Laniel <francis.laniel at amarulasolutions.com>
> > Tested-by: Tony Dinh <mibodhi at gmail.com>
> > [1] https://github.com/gcc-mirror/gcc/blob/4f181f9c7ee3efc509d185fdfda33be9018f1611/libgcc/config/arm/lib1funcs.S#L2156
> 
> Thanks for the patch! I've added Tom, Pali, and Stefan.

Looks good,

Acked-by: Pali Rohár <pali at kernel.org>

> I think we need to do some more testing for other boards that have
> CONFIG_HAS_THUMB2 and CONFIG_SPL_SYS_THUMB_BUILD. My test target
> (Marvell Armada 385 SoC) is somewhat broken right now. So it will take
> some time for me to get that back running to run this test.
> 
> All the best,
> Tony
> 
> > ---
> >  arch/arm/lib/lib1funcs.S | 17 +++++++++++++++++
> >  1 file changed, 17 insertions(+)
> >
> > diff --git a/arch/arm/lib/lib1funcs.S b/arch/arm/lib/lib1funcs.S
> > index 7ff4446dd6..79cedc0aad 100644
> > --- a/arch/arm/lib/lib1funcs.S
> > +++ b/arch/arm/lib/lib1funcs.S
> > @@ -424,4 +424,21 @@ ENTRY(__gnu_thumb1_case_uhi)
> >         ret     lr
> >  ENDPROC(__gnu_thumb1_case_uhi)
> >  .popsection
> > +
> > +/* Taken and adapted from: https://github.com/gcc-mirror/gcc/blob/4f181f9c7ee3efc509d185fdfda33be9018f1611/libgcc/config/arm/lib1funcs.S#L2156 */
> > +.pushsection .text.__gnu_thumb1_case_si, "ax"
> > +ENTRY(__gnu_thumb1_case_si)
> > +       push    {r0, r1}
> > +       mov     r1, lr
> > +       adds    r1, r1, #2      /* Align to word.  */
> > +       lsrs    r1, r1, #2
> > +       lsls    r0, r0, #2
> > +       lsls    r1, r1, #2
> > +       ldr     r0, [r1, r0]
> > +       adds    r0, r0, r1
> > +       mov     lr, r0
> > +       pop     {r0, r1}
> > +       mov     pc, lr          /* We know we were called from thumb code.  */
> > +ENDPROC(__gnu_thumb1_case_si)
> > +.popsection
> >  #endif
> > --
> > 2.34.1
> >