Re: [PATCH] Merge from LTO: eh_personality changes

[Richard Guenther <rguenther at suse dot de>]

On Thu, 10 Sep 2009, Richard Guenther wrote:

> On Tue, 8 Sep 2009, Richard Henderson wrote:
> 
> > On 09/08/2009 08:20 AM, Richard Guenther wrote:
> > > > Ok.  I'll modify the patch to make this a true langhook and maybe move
> > > > the eh-personality also to a langhook called from eh lowering.
> > > 
> > > The latter is difficult as C++ is playing some tricks with Java vs.
> > > non-Java personality, so I leave that alone for now.
> > 
> > Ew.
> > 
> > > FYI the following two patches would implement the above (untested).
> > 
> > Looks good.
> 
> I've been playing a bit with optimizing setting of 
> DECL_FUNCTION_EH_PERSONALITY only if the function uses EH types
> instead of just checking for an empty EH region tree.  It doesn't look
> like its very simple - even a catch (...) needs a personality routine.
> 
> So I am now testing the following - the ERT_ALLOWED_EXCEPTIONS case
> is required to get diagnostics from g++.dg/torture/pr34850.C which
> requires inlining memset into clear_mem.
> 
> If that doesn't work out I'll refrain from optimizing at all and
> just disable cross different EH personality TU inlining completely
> (that already passed bootstrapping and testing, it would be
> -  if (function_needs_eh_personality (cfun))
> -    DECL_FUNCTION_PERSONALITY (current_function_decl) = 
> eh_personality_decl;
> +  DECL_FUNCTION_PERSONALITY (current_function_decl) = 
> eh_personality_decl;
> meaning no functional change as far as trunk is concerned)

Doesn't seem to work.  Instead I tried to fall back to
the gcc personality for detecting empty type lists, again setting
a cfi personality for all functions we emit.  But that doesn't work
either (it seems catch (...) doesn't work with the gcc personality,
g++.dg/eh/loop1.C fails).

Bah.

So, ok without trying to be clever about inlining cross personality
for now?

Thanks,
Richard.