[Bug tree-optimization/59209] builtin memcpy in inlined function is not optimized away if count is derived from src pointer difference

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59209

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |DUPLICATE

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
We simply are not able to optimize x + 1 - x to 1.  See also PR58742
for which I think this is a dup.

  _2 = x_1(D) + 1;
  src_end.1_8 = (long int) _2;
  src_start.2_9 = (long int) x_1(D);
  _10 = src_end.1_8 - src_start.2_9;
  _11 = (long unsigned int) _10;
  __builtin_memcpy (&r, x_1(D), _11);

later on RTL we optimize the size argument to 1 but that's too late.

*** This bug has been marked as a duplicate of bug 58742 ***