[Bug tree-optimization/127101] New: a+b when b is non-zero and it is known there is no overflow (due to a check) implies a+b is non-zero

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127101

            Bug ID: 127101
           Summary: a+b when b is non-zero and it is known there is no
                    overflow (due to a check) implies a+b is non-zero
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
            Blocks: 85316
  Target Milestone: ---

Created attachment 65431
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=65431&action=edit
testcase

Take the attached testcase.  Both of these functions should reduce to just
return 1;

I think this comes from std::vector::_M_check_len but I am not 100% sure.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85316
[Bug 85316] [meta-bug] VRP range propagation missed cases