[Bug tree-optimization/96923] New: Failure to optimize a select-related bool pattern to or+not

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96923

            Bug ID: 96923
           Summary: Failure to optimize a select-related bool pattern to
                    or+not
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

_Bool f2(_Bool a, _Bool b)
{
    return !a ? !b : 0;
}

This can be optimized to `return !(a | b);`. This transformation is done by
LLVM, but not by GCC.