https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68404
Bill Schmidt <wschmidt at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org,
| |meissner at gcc dot gnu.org,
| |rguenth at gcc dot gnu.org,
| |segher at gcc dot gnu.org
--- Comment #11 from Bill Schmidt <wschmidt at gcc dot gnu.org> ---
After discussing with Segher offline, I think the way forward will be to change
the definition of these fusion peepholes for now. Instead of nesting the plus,
we can probably just add an argument to the UNSPEC to keep track of the extra
operand. If necessary, we can perhaps add a note to hold the full address; not
sure that the final few passes would care.
This would be just a workaround for GCC 6 since this should really be
considered a blocker. In GCC 7 the fusion patterns are supposed to be
introduced earlier and last longer, and the nested plus will cause difficulties
all over the place, so this needs to be rethought.
CCing the release managers for consideration of this as a P1 blocker.
