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Re: [RFA] Fix Ada bootstrap (was: 16: EH redirection)
> On Thu, Apr 30, 2009 at 12:50 PM, Jan Hubicka <hubicka@ucw.cz> wrote:
> > I do not know how to fix this properly. ?I can either make DCE to not
> > remove unreachable blocks and remove them somewhere later, or simply
> > drop DCE flag on DSE df_analyze or declare that it is up to caller to
> > cleanup CFG after calling df_analyze with DCE flag when df_analyze
> > somehow signalizes that it removed some throwing instructions or make
> > DCE to update the bitmap?
>
> I'd let DCE update the bitmap. It should know which blocks have
> disappeared (we're not running compact_blocks, right?)
That would imply passing the bitmap around to DCE, writting custom
version of delete_unreachable_blocks (that is not big deal given it is
single loop checking reachability flag and calling delete_block). But I
am bit concerned about fact that the passes calling df_analyze with a
bitmap often use the bitmap later. I don't think they expect the bitmap
to change? I.e. DSE itself it attaching info to BBs, computing the
bitmap, the calling analyze and I think it will just leak the info if
the BB disappears.
Honza
>
> Ciao!
> Steven