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* [Bug tree-optimization/115035] New: Missed optimization: fold min/max in phi
@ 2024-05-10 15:08 xxs_chy at outlook dot com
  2024-05-18 19:52 ` [Bug tree-optimization/115035] " pinskia at gcc dot gnu.org
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: xxs_chy at outlook dot com @ 2024-05-10 15:08 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115035

            Bug ID: 115035
           Summary: Missed optimization: fold min/max in phi
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: xxs_chy at outlook dot com
  Target Milestone: ---

Godbolt link: https://godbolt.org/z/o489f6sj5
```
bool src(unsigned a, unsigned b, bool c) {
    unsigned phi;
    if(c) {
        dummy();
        phi = a < 6 ? a : 6;
    } else {
        phi = b;
    }
    return phi < 6;
}
```

can be folded to:

```
bool tgt(unsigned a, unsigned b, bool c) {
    unsigned phi;
    if(c) {
        dummy();
        phi = a;
    } else {
        phi = b;
    }
    return phi < 6;
}
```

^ permalink raw reply	[flat|nested] 4+ messages in thread
* [Bug tree-optimization/115035] Missed optimization: fold min/max in phi
  2024-05-10 15:08 [Bug tree-optimization/115035] New: Missed optimization: fold min/max in phi xxs_chy at outlook dot com
@ 2024-05-18 19:52 ` pinskia at gcc dot gnu.org
  2024-05-18 19:57 ` pinskia at gcc dot gnu.org
  2024-05-23 12:21 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-05-18 19:52 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115035

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/115035] Missed optimization: fold min/max in phi
  2024-05-10 15:08 [Bug tree-optimization/115035] New: Missed optimization: fold min/max in phi xxs_chy at outlook dot com
  2024-05-18 19:52 ` [Bug tree-optimization/115035] " pinskia at gcc dot gnu.org
@ 2024-05-18 19:57 ` pinskia at gcc dot gnu.org
  2024-05-23 12:21 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-05-18 19:57 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115035

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2024-05-18

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed. GCC does have some code that handles some of this in phiopt but not
in a generic way.

Jump threading can handle:
```
int src1(unsigned a, unsigned b, int c) {
    unsigned phi;
    if(c) {
        dummy();
        phi = a < 5 ? a : 5;
    } else {
        phi = b;
    }
    if (phi < 6)
      dummy();
}
```

But not:
```
int src(unsigned a, unsigned b, int c) {
    unsigned phi;
    if(c) {
        dummy();
        phi = a < 5 ? a : 5;
    } else {
        phi = b;
    }
    return (phi < 6);
     dummy();
}
```

^ permalink raw reply	[flat|nested] 4+ messages in thread
* [Bug tree-optimization/115035] Missed optimization: fold min/max in phi
  2024-05-10 15:08 [Bug tree-optimization/115035] New: Missed optimization: fold min/max in phi xxs_chy at outlook dot com
  2024-05-18 19:52 ` [Bug tree-optimization/115035] " pinskia at gcc dot gnu.org
  2024-05-18 19:57 ` pinskia at gcc dot gnu.org
@ 2024-05-23 12:21 ` pinskia at gcc dot gnu.org
  2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-05-23 12:21 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115035

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

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

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

*** This bug has been marked as a duplicate of bug 114273 ***

^ permalink raw reply	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2024-05-23 12:21 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2024-05-10 15:08 [Bug tree-optimization/115035] New: Missed optimization: fold min/max in phi xxs_chy at outlook dot com
2024-05-18 19:52 ` [Bug tree-optimization/115035] " pinskia at gcc dot gnu.org
2024-05-18 19:57 ` pinskia at gcc dot gnu.org
2024-05-23 12:21 ` pinskia at gcc dot gnu.org

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