> On Wed, Feb 21, 2018 at 08:09:28PM +0100, Jan Hubicka wrote:
> > --- ipa-cp.c (revision 257844)
> > +++ ipa-cp.c (working copy)
> > @@ -630,6 +630,24 @@ determine_versionability (struct cgraph_
> > reason = "calls comdat-local function";
> > }
> >
> > + /* Functions calling BUILT_IN_VA_ARG_PACK and BUILT_IN_VA_ARG_PACK_LEN
> > + works only when inlined. Cloning them may still lead to better code
>
> s/works/work/
>
> > + becuase ipa-cp will not give up on cloning further. If the function
> > is
>
> s/becuase/because/
>
> > + external this however leads to wrong code becuase we may end up
> > producing
>
> s/becuase/because/
Thanks, fixed.
>
> > + offline copy of the function. */
> > + if (DECL_EXTERNAL (node->decl))
> > + for (cgraph_edge *edge = node->callees; !reason && edge;
> > + edge = edge->next_callee)
> > + if (DECL_BUILT_IN (edge->callee->decl)
> > + && DECL_BUILT_IN_CLASS (edge->callee->decl) == BUILT_IN_NORMAL)
> > + {
> > + if (DECL_FUNCTION_CODE (edge->callee->decl) == BUILT_IN_VA_ARG_PACK)
> > + reason = "external function which calls va_arg_pack";
> > + if (DECL_FUNCTION_CODE (edge->callee->decl)
> > + == BUILT_IN_VA_ARG_PACK_LEN)
> > + reason = "external function which calls va_arg_pack_len";
> > + }
> > +
> > if (reason && dump_file && !node->alias && !node->thunk.thunk_p)
> > fprintf (dump_file, "Function %s is not versionable, reason: %s.\n",
> > node->dump_name (), reason);
>
> Do you have a testcase for this, or is it LTO with too large input?
There is reduced testcase in the PR which probably should be rejected by C
frontend because it is uses va_arg_pack on non-variadic function.
I plan to send additional patches and then come with a testcase (because current
one should be early inlined and thus it will stop testing ipa-cp)
Honza
