On January 29, 2016 6:34:50 PM GMT+01:00, Bernd Schmidt <bschm...@redhat.com> wrote: >So PR57193 has an example of sub-optimal code generation, with some >unnecessary register moves left after LRA. These seem to be difficult >to >prevent, but last year Robert Suchanek made some modifications to >regrename that allow it to clean up such cases. Enabling >-frename-registers removes one of the two unnecessary copies, and I'm >pretty sure I could make it eliminate the other one as well with a bit >more work. > >Hence, this patch. The renamer has seen a lot of fixes over the years >and should be in pretty good shape IMO. Still, I won't deny that this >is >a bit riskier than the usual bugfix patch at this stage. > >Bootstrapped and tested on x86_64-linux, with my earlier patch to fix >some i386 tests. Thoughts? Should we do this for gcc-7 at least?
I don't think it's appropriate at this stage. Richard. > >Bernd