Re: [PATCH] ipa-visibility: Optimize TLS access [PR99619]

[Alexander Monakov <amonakov@ispras.ru>]

On Mon, 16 May 2022, Alexander Monakov wrote:

> On Mon, 9 May 2022, Jan Hubicka wrote:
> 
> > > On second thought, it might be better to keep the assert, and place the loop
> > > under 'if (optimize)'?
> > 
> > The problem is that at IPA level it does not make sense to check
> > optimize flag as it is function specific.  (shlib is OK to check it
> > anywhere since it is global.)
> > 
> > So I think we really want to run the code only at the WPA time
> > (symtab_state>=IPA_SSA) and we want to see what is optimization flag of
> > those function referring the variable since that is what decided codegen
> > we will produce.
> 
> Perhaps I misunderstood the issue. Are you saying that there might be no -O
> option on lto1 command line, because lto1 is supposed to take optimization
> level from function summaries, but during pass_ipa_whole_program_visibility
> there's no "current function" so 'optimize' is at its default value (zero)?
> 
> And the solution is to iterate over referring functions to see if at least
> one of them satisfies 'opt_for_fn (decl, optimize) > 0'?

Do you want to see a patch implementing the above solution?

Alexander