[Bug target/86952] Avoid jump table for switch statement with -mindirect-branch=thunk

marxin at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Thu Nov 22 11:55:00 GMT 2018


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86952

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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           Assignee|unassigned at gcc dot gnu.org      |marxin at gcc dot gnu.org

--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
(In reply to H.J. Lu from comment #3)
> (In reply to Martin Liška from comment #2)
> > H.J. I can write a patch for it. Do you expect more expensive costs when
> > retpolines are enabled?
> 
> retpoline is more expensive than 4 branches.

Can you please make a microbenchmark that will expose how exactly is that
expensive? Based on that I can tune current costs.


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