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* [Bug tree-optimization/16427] dead memset not optimized away
       [not found] <bug-16427-4@http.gcc.gnu.org/bugzilla/>
@ 2011-03-09 14:56 ` rguenth at gcc dot gnu.org
  0 siblings, 0 replies; 2+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-03-09 14:56 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16427

--- Comment #5 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-03-09 14:56:26 UTC ---
Related to this is

struct X { int i; int j; int k; };
void foo (void)
{
  struct X a, b;
  __builtin_memcpy (&a, &b, 4);
}

where we are unable to DCE the memcpy call.

Both issues should be tackled at tree DCE level by better handling of
aliased (local) variables.  Needs the same infrastructure changes as
PR41490.


^ permalink raw reply	[flat|nested] 2+ messages in thread

* [Bug tree-optimization/16427] dead memset not optimized away
       [not found] <bug-16427-7834@http.gcc.gnu.org/bugzilla/>
@ 2010-06-09 12:00 ` rguenth at gcc dot gnu dot org
  0 siblings, 0 replies; 2+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2010-06-09 12:00 UTC (permalink / raw)
  To: gcc-bugs



------- Comment #4 from rguenth at gcc dot gnu dot org  2010-06-09 11:59 -------
It's now optimized by RTL DSE but we keep the stack allocated.

Re-confirmed on the tree-level.  Should be easy to extend DSE to handle this.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2006-10-22 22:17:10         |2010-06-09 11:59:50
               date|                            |
            Summary|dead 0 memset not optimized |dead memset not optimized
                   |away                        |away


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16427


^ permalink raw reply	[flat|nested] 2+ messages in thread

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     [not found] <bug-16427-7834@http.gcc.gnu.org/bugzilla/>
2010-06-09 12:00 ` rguenth at gcc dot gnu dot org

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