https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107822
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|13.0 |14.0
Summary|[13 Regression] Dead Code |[13/14 Regression] Dead
|Elimination Regression at |Code Elimination Regression
|-Os (trunk vs. 12.2.0) |at -Os (trunk vs. 12.2.0)
Priority|P1 |P2
--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
I don't see us realistically fixing this for GCC 13, so postponing to GCC 14
and downgrading from P1 to P2.
Besides bringing back a pass that performs propagation itself possibly using
value-range and range-op helpers it might be possible to teach the on-demand
ranger to process SSA SCCs in the special way the old code did (but
only when asked for?). But teaching ranger about SCCs probably requires
extensive changes in the code doing the global "propagation", and I'm not
sure that's a) desirable or b) even possible in some reasonable manner.
Adding ad-hoc SCC discovery ontop of the existing "propagation" probably
does not make much sense.
