[Bug tree-optimization/79716] memset followed by overwrite not eliminated

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79716

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

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

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note g in comment #0 was fixed in GCC 7 (r7-5963-gd155c6fef06cba):
  Deleted dead call: memset (p_3, 0, 16);

I am going to see what is needed to be done for the non-constant case.

simplify_builtin_call in tree-ssa-forwprop most likely can be improved to do
it.