[rs6000] -mno-sched-prolog vs .debug_frame

[David Edelsohn]

On Fri, Jul 1, 2011 at 8:31 PM, Richard Henderson <rth@redhat.com> wrote:
> The implementation of TARGET_SCHED_PROLOG is incompatible with
> some coming changes to how dwarf2 cfi is to be generated.
>
> Some suggested solutions are:
>
>  (1) Remove the option.  Is it really that interesting
>     beyond -mno-sched-insns2?
>
>  (2) Emit blockage insns at the end of the prologue
>     and the beginning of the epilogue.  That'll prevent
>     the majority of the changes that scheduling could
>     introduce.
>
>  (3) Emit the prologue and epilogue somewhere after
>     scheduling and before final.  E.g. md_reorg.
>
> I'd be delighted if someone could actually implement one
> of these changes at some point in the next week, but
> failing that please weigh in on the preferred solution.

As we discussed on IRC, (1) with and eventual implementation of (2) are okay.

Thanks, David