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* [Bug tree-optimization/57567] New: Missed optimsation : compare + or
@ 2013-06-08 15:42 john@bass-software.com
  2013-06-10  8:44 ` [Bug tree-optimization/57567] Missed optimisation: " rguenth at gcc dot gnu.org
  2021-07-20  2:34 ` pinskia at gcc dot gnu.org
  0 siblings, 2 replies; 3+ messages in thread
From: john@bass-software.com @ 2013-06-08 15:42 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57567

            Bug ID: 57567
           Summary: Missed optimsation : compare + or
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: john@bass-software.com

Using 4.9.0 20130608 (experimental) [trunk revision 199851], target
arm-unknown-eabi.

The following case produces suboptimal code:

unsigned
test (unsigned t)
{
  if (t != (unsigned)-1)
    t |= 3;
  return t;
}

Result:

    cmn    r0, #1
    orrne    r0, r0, #3

A simple:

    orr    r0, r0, #3

would be enough.


^ permalink raw reply	[flat|nested] 3+ messages in thread

* [Bug tree-optimization/57567] Missed optimisation: compare + or
  2013-06-08 15:42 [Bug tree-optimization/57567] New: Missed optimsation : compare + or john@bass-software.com
@ 2013-06-10  8:44 ` rguenth at gcc dot gnu.org
  2021-07-20  2:34 ` pinskia at gcc dot gnu.org
  1 sibling, 0 replies; 3+ messages in thread
From: rguenth at gcc dot gnu.org @ 2013-06-10  8:44 UTC (permalink / raw)
  To: gcc-bugs

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57567

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |missed-optimization
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-06-10
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  ISTR Jakub did some work in this area.


^ permalink raw reply	[flat|nested] 3+ messages in thread

* [Bug tree-optimization/57567] Missed optimisation: compare + or
  2013-06-08 15:42 [Bug tree-optimization/57567] New: Missed optimsation : compare + or john@bass-software.com
  2013-06-10  8:44 ` [Bug tree-optimization/57567] Missed optimisation: " rguenth at gcc dot gnu.org
@ 2021-07-20  2:34 ` pinskia at gcc dot gnu.org
  1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2021-07-20  2:34 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57567

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
   Target Milestone|---                         |7.0
           Severity|normal                      |enhancement
         Resolution|---                         |FIXED

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fixed for a while now.  Maybe before even GCC 7.

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-07-20  2:34 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2013-06-08 15:42 [Bug tree-optimization/57567] New: Missed optimsation : compare + or john@bass-software.com
2013-06-10  8:44 ` [Bug tree-optimization/57567] Missed optimisation: " rguenth at gcc dot gnu.org
2021-07-20  2:34 ` pinskia at gcc dot gnu.org

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