[Bug tree-optimization/116117] New: late_warn_uninitialized should just split edges directly instead of using the pass manager

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116117

            Bug ID: 116117
           Summary: late_warn_uninitialized should just split edges
                    directly instead of using the pass manager
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Keywords: internal-improvement
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Right now we have (which was added with r0-125162-g5c2961cf38a69f ):
      /* Split critical edges before late uninit warning to reduce the
         number of false positives from it.  */
      NEXT_PASS (pass_split_crit_edges);
      NEXT_PASS (pass_late_warn_uninitialized);


(in 2 places, one for -Og). After r8-2993-ga7976089dba5e2 (which made PRE do
the splitting internally), this place was the only place which had did the
split critical edges using the pass manager. 

This is a nice cleanup and allows us to remove fully the pass split_crit_edges.