RE: [PATCH 9/15] arm: Set again stack pointer as CFA reg when popping if necessary

[Kyrylo Tkachov via Gcc-patches]

> -----Original Message-----
> From: Andrea Corallo <andrea.cora...@arm.com>
> Sent: Tuesday, September 27, 2022 11:06 AM
> To: Kyrylo Tkachov <kyrylo.tkac...@arm.com>
> Cc: Andrea Corallo via Gcc-patches <gcc-patches@gcc.gnu.org>; Richard
> Earnshaw <richard.earns...@arm.com>; nd <n...@arm.com>
> Subject: Re: [PATCH 9/15] arm: Set again stack pointer as CFA reg when
> popping if necessary
> 
> Kyrylo Tkachov <kyrylo.tkac...@arm.com> writes:
> 
> > Hi Andrea,
> >
> >> -----Original Message-----
> >> From: Gcc-patches <gcc-patches-
> >> bounces+kyrylo.tkachov=arm....@gcc.gnu.org> On Behalf Of Andrea
> >> Corallo via Gcc-patches
> >> Sent: Friday, August 12, 2022 4:34 PM
> >> To: Andrea Corallo via Gcc-patches <gcc-patches@gcc.gnu.org>
> >> Cc: Richard Earnshaw <richard.earns...@arm.com>; nd <n...@arm.com>
> >> Subject: [PATCH 9/15] arm: Set again stack pointer as CFA reg when
> popping
> >> if necessary
> >>
> >> Hi all,
> >>
> >> this patch enables 'arm_emit_multi_reg_pop' to set again the stack
> >> pointer as CFA reg when popping if this is necessary.
> >>
> >
> > From what I can tell from similar functions this is correct, but could you
> elaborate on why this change is needed for my understanding please?
> > Thanks,
> > Kyrill
> 
> Hi Kyrill,
> 
> sure, if the frame pointer was set, than it is the current CFA register.
> If we request to adjust the current CFA register offset indicating it
> being SP (while it's actually FP) that is indeed not correct and the
> incoherence we will be detected by an assertion in the dwarf emission
> machinery.

Thanks,  the patch is ok
Kyrill

> 
> Best Regards
> 
>   Andrea