Re: [PATCH] PR 32475 stack setup code being deleted.

["Seongbae Park (박성배, 朴成培)" <seongbae dot park at gmail dot com>]

On 7/3/07, Paolo Bonzini <paolo.bonzini@lu.unisi.ch> wrote:
> Seongbae Park wrote:
> > Attached is the patch to fix 32475
> > where the stack pointer becomes dead after epilogue generation,
> > due to the stack pointer restoration codein the epilogue.
> > The patch adds a df_ref of use of the stack pointer
> > for every write to the stack pointer - which essentially keeps
> > the stack pointer alive always.
>
> So, why not munging the live bitmaps directly, so that when the frame
> pointer is live, the stack pointer is too?
>
> Paolo

I'd like to avoid munging the live bitmaps for various reasons:
1) munging the live vector doesn't give us the correct reg chain.
2) munging is more fragile - scanning is the lower layer than live analysis,
and this fix is very small in the size, with effectively the same outcome.
--
#pragma ident "Seongbae Park, compiler, http://seongbae.blogspot.com";