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* [Bug tree-optimization/109906] New: a rrotate (32-b) -> a lrotate b
@ 2023-05-19  8:05 pinskia at gcc dot gnu.org
  2023-11-09  6:26 ` [Bug tree-optimization/109906] " pinskia at gcc dot gnu.org
  0 siblings, 1 reply; 2+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-05-19  8:05 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109906

            Bug ID: 109906
           Summary: a rrotate (32-b) -> a lrotate b
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Take:
```
static inline
unsigned rotateright(unsigned x, int t)
{
  if (t >= 32) __builtin_unreachable();
  unsigned tl = x >> (t);
  unsigned th = x << (32-t);
  return tl | th;
}

unsigned rotateleft(unsigned t, int x)
{
  return rotate (t, 32-x);
}
```

I would have assumed GCC would produce a rotate left for rotateleft but does
not currently.

^ permalink raw reply	[flat|nested] 2+ messages in thread
* [Bug tree-optimization/109906] a rrotate (32-b) -> a lrotate b
  2023-05-19  8:05 [Bug tree-optimization/109906] New: a rrotate (32-b) -> a lrotate b pinskia at gcc dot gnu.org
@ 2023-11-09  6:26 ` pinskia at gcc dot gnu.org
  0 siblings, 0 replies; 2+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-11-09  6:26 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109906

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
   Last reconfirmed|                            |2023-11-09
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Mine.

^ permalink raw reply	[flat|nested] 2+ messages in thread
end of thread, other threads:[~2023-11-09  6:26 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
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2023-05-19  8:05 [Bug tree-optimization/109906] New: a rrotate (32-b) -> a lrotate b pinskia at gcc dot gnu.org
2023-11-09  6:26 ` [Bug tree-optimization/109906] " pinskia at gcc dot gnu.org

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