[Bug tree-optimization/117385] New: Move phiopt away from doing a COND_EXPR with a comparison as first operand

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117385

            Bug ID: 117385
           Summary: Move phiopt away from doing a COND_EXPR with a
                    comparison as first operand
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Keywords: internal-improvement
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
          Assignee: pinskia at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

As mentioned on
https://gcc.gnu.org/pipermail/gcc-patches/2024-October/666831.html :
```
The biggest offender still present is phiopt building a GENERIC
comparison for the
piecewise COND_EXPR simplification in gimple_simplify_phiopt (so
genmatch needs to
create both GIMPLE and GENERIC match variants for COND_EXPR conditions).
maybe_fold_comparisons_from_match_pd uses on-stack temporary GIMPLE for
a similar (more complex) case.
```