[Bug tree-optimization/105142] [12 Regression] Wrong code with -O2 since r12-2591

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105142

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |rguenth at gcc dot 
gnu.org
             Status|NEW                         |ASSIGNED
           Keywords|                            |wrong-code

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Let me take a stab at this.  We can enhance

        if (tree_ssa_ifcombine_bb (bb))
          {
            /* Clear range info from all stmts in BB which is now executed
               conditional on a always true/false condition.  */
            reset_flow_sensitive_info_in_bb (bb);
            cfg_changed |= true;

or adjust bb_no_side_effects_p (which already checks
gimple_uses_undefined_value_p).