Re: [PATCH] cgraph: Handle simd clones in cgraph_node::set_{const,pure}_flag [PR106433]

[Jakub Jelinek <jakub@redhat.com>]

On Wed, Feb 08, 2023 at 06:10:08PM +0100, Jan Hubicka wrote:
> My understanding of simd clones is bit limited, but I think you are
> right that they should have the same semantics as their caller.
> 
> I think const may be one that makes compiler to ICE, but
> there are many other places where function body is analyzed and all its
> aliases/thunks and other variants should be updated too.  For exmaple
> set_pure_flag, nothrow, noreturn and analysis done by modref,
> ipa-refernece etc.
> 
> I wonder if we want to update them all and hide that in some
> abstraction?  Next stage 1 I can work on inventing iterators for those
> kind of things as current approach combinindg direct walkters and
> function wrappers has become bit hard to maintain in cases like this.

I think it depends on whether we do that analysis or update it post IPA
or not.  Because simd clones are created very late during IPA, if say
the nothrow, noreturn, modref etc. analysis is done only during IPA or
before it, we don't need to walk the simd clones.
It is just for late GIMPLE analysis that changes flags that later on
could be used in callers of those functions.
pure/const flag is what I know can happen this late, what else?

	Jakub