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* [Bug tree-optimization/108133] New: Failure to merge conditional bit clears
@ 2022-12-15 18:26 rguenth at gcc dot gnu.org
  2022-12-15 18:35 ` [Bug tree-optimization/108133] " pinskia at gcc dot gnu.org
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-12-15 18:26 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108133

            Bug ID: 108133
           Summary: Failure to merge conditional bit clears
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rguenth at gcc dot gnu.org
  Target Milestone: ---

void foo (int *p)
{
  if (*p & (1<<3))
    *p &= ~(1<<3);
  if (*p & (1<<5))
    *p &= ~(1<<5);
  if (*p & (1<<6))
    *p &= ~(1<<6);
}

could be optimized to

  if (*p & ((1<<3)|(1<<5)|(1<<6)))
    *p &= ~((1<<3)|(1<<5)|(1<<6));

We have such code in tree-inline.cc:

      /* Clear flags that need revisiting.  */
      if (gcall *call_stmt = dyn_cast <gcall *> (copy))
        {
          if (gimple_call_tail_p (call_stmt))
            gimple_call_set_tail (call_stmt, false);
          if (gimple_call_from_thunk_p (call_stmt))
            gimple_call_set_from_thunk (call_stmt, false);

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [Bug tree-optimization/108133] Failure to merge conditional bit clears
  2022-12-15 18:26 [Bug tree-optimization/108133] New: Failure to merge conditional bit clears rguenth at gcc dot gnu.org
@ 2022-12-15 18:35 ` pinskia at gcc dot gnu.org
  2022-12-15 18:37 ` pinskia at gcc dot gnu.org
  2022-12-15 18:42 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2022-12-15 18:35 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108133

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |missed-optimization

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I think there is a dup of this bug already ...

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [Bug tree-optimization/108133] Failure to merge conditional bit clears
  2022-12-15 18:26 [Bug tree-optimization/108133] New: Failure to merge conditional bit clears rguenth at gcc dot gnu.org
  2022-12-15 18:35 ` [Bug tree-optimization/108133] " pinskia at gcc dot gnu.org
@ 2022-12-15 18:37 ` pinskia at gcc dot gnu.org
  2022-12-15 18:42 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2022-12-15 18:37 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108133

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |enhancement

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [Bug tree-optimization/108133] Failure to merge conditional bit clears
  2022-12-15 18:26 [Bug tree-optimization/108133] New: Failure to merge conditional bit clears rguenth at gcc dot gnu.org
  2022-12-15 18:35 ` [Bug tree-optimization/108133] " pinskia at gcc dot gnu.org
  2022-12-15 18:37 ` pinskia at gcc dot gnu.org
@ 2022-12-15 18:42 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2022-12-15 18:42 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108133

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-12-15
     Ever confirmed|0                           |1

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed.

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2022-12-15 18:42 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2022-12-15 18:26 [Bug tree-optimization/108133] New: Failure to merge conditional bit clears rguenth at gcc dot gnu.org
2022-12-15 18:35 ` [Bug tree-optimization/108133] " pinskia at gcc dot gnu.org
2022-12-15 18:37 ` pinskia at gcc dot gnu.org
2022-12-15 18:42 ` pinskia at gcc dot gnu.org

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