[Bug target/84570] [og7, openacc, nvptx] Unused offloaded function parameters

["cesar at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84570

cesar at gcc dot gnu.org changed:

           What    |Removed                     |Added
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                 CC|                            |cesar at gcc dot gnu.org

--- Comment #1 from cesar at gcc dot gnu.org ---
First, variable 'i' is private, so it shouldn't require a param argument.

What we really need here is proper data flow analysis during gimplification.
That would solve a lot of performance issues, including privatizing
uninitialized, privatizing variables only live inside a parallel region, not
transferring unused variables, not copying out dead variables, etc. 

I like the idea of privatizing uninitialized variables, but if I'm not
mistaken, that would still require DF information. It looks like that
information doesn't become available until the gimple code goes into SSA.

As an alternative, I proposed postponing the outlining of omp/acc regions until
the SSA information is available. But then that approach would have its own set
of problems.