[Bug tree-optimization/111764] [11/12/13/14 Regression] Wrong code at -O3 on x86_64-linux-gnu

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111764

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

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

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
OK, so the vectorizer transforms

 b = 2;
 for (;;)
   b = b * b;

to

 b = 1;
 for (;;)
   b = b * b;
 b *= 2;

which is obviously wrong(TM).