https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80293
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |missed-optimization
Priority|P3 |P2
Component|c++ |tree-optimization
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #1)
> Started with r227901, the complete scalarization is not really helpful here,
> and unfortunately gimple-ssa-store-merging.c only merges now adjacent
> constant stores, not adjacent loads followed by adjacent stores of the
> loaded values to undo the damage.
> Not sure what would be easier here, if some heuristics during SRA whether
> the scalarization is helpful or not, or improving gimple-ssa-store-merging.c.
We have another bugreport that complains about SRA and Martin said he had
patches but intended to wait for GCC 8.
Improving sotre-merging is of course good anyway (the user may have written the
code in the "bad" way).
Note that I believe that store-merging, SRA (and bswap) are all passes that
should be merged given they perform similar analyses and transforms.
