[Bug target/69459] New: [5/6 Regression] wrong code with -O2 and vector arithmetics @ x86_64

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69459

            Bug ID: 69459
           Summary: [5/6 Regression] wrong code with -O2 and vector
                    arithmetics @ x86_64
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu
            Target: x86_64-*

Created attachment 37450
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37450&action=edit
reduced testcase

Output:
$ x86_64-pc-linux-gnu-gcc -O2 testcase.c
$ ./a.out
ffffffffe000000b
Aborted

Tested revisions:
trunk r232760 - FAIL
5-branch r232545 - FAIL
4_[987]-branch - OK