Re: [PATCH] Fix ICEs with "omp declare simd" attribute on versioned fns or omp_fn* (PR middle-end/83977)

[Richard Biener <rguenther at suse dot de>]

On January 24, 2018 5:16:45 PM GMT+01:00, Jakub Jelinek <jakub@redhat.com> wrote:
>On Wed, Jan 24, 2018 at 05:08:10PM +0100, Richard Biener wrote:
>> >The "omp declare simd" attribute refers to argument numbers of the
>> >functions, so trying to apply it on versioned functions that can
>> >perhaps
>> >have different number and types of arguments results in ICEs or
>> >wrong-code.
>> >Unfortunately, if simd attribute or #pragma omp declare simd is used
>> >on C++ ctors or dtors, those have DECL_ABSTRACT_ORIGIN of something
>> >that
>> >really doesn't exist, abstract ctor or dtor, so checking if
>> >the types of node->decl and its DECL_ABSTRACT_ORIGIN are compatible
>> >function
>> >types doesn't work.
>> 
>> So if the attribute is on the decl we clone it should be in the list
>of things that cloning adjusts or blocks cloning. 
>
>Yeah, guess I could move the attribute removal code from omp-low.c to
>some
>helper function and in tree_function_versioning check if the attribute
>is
>present and if yes and the old/new function types don't match, drop the
>attribute.  Or, add some flag to cgraph whether the attribute should be
>honored or not, and clear it in tree_function_versioning and
>omp_create_child_function instead of removing the attribute.

I think there's already a set of attributes that prevent cloning and or are adjusted by the IPA param machinery. The Martins or Honza should know better. 

>I'd prefer to defer that to GCC9 though at this point.

Sure. 

>	Jakub