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* [Bug c/115023] New: __builtin_assoc_barrier does not talk about contracting even though it prevents it too
@ 2024-05-10  6:15 pinskia at gcc dot gnu.org
  2024-05-10  6:15 ` [Bug c/115023] " pinskia at gcc dot gnu.org
  2024-05-10 12:37 ` rguenth at gcc dot gnu.org
  0 siblings, 2 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-05-10  6:15 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115023

            Bug ID: 115023
           Summary: __builtin_assoc_barrier does not talk about
                    contracting even though it prevents it too
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Keywords: documentation
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Take:
```
float foo(float a, float b, float c) {
  return __builtin_assoc_barrier(a * b) + c;
}
```
On aarch64 (or on x86_64 with -mfma), this will prevent the generation of FMA
but the documentation does not mention that even though this is by design.

^ permalink raw reply	[flat|nested] 3+ messages in thread
* [Bug c/115023] __builtin_assoc_barrier does not talk about contracting even though it prevents it too
  2024-05-10  6:15 [Bug c/115023] New: __builtin_assoc_barrier does not talk about contracting even though it prevents it too pinskia at gcc dot gnu.org
@ 2024-05-10  6:15 ` pinskia at gcc dot gnu.org
  2024-05-10 12:37 ` rguenth at gcc dot gnu.org
  1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-05-10  6:15 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115023

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|                            |2024-05-10
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I will write up something about this for the documentation.

^ permalink raw reply	[flat|nested] 3+ messages in thread
* [Bug c/115023] __builtin_assoc_barrier does not talk about contracting even though it prevents it too
  2024-05-10  6:15 [Bug c/115023] New: __builtin_assoc_barrier does not talk about contracting even though it prevents it too pinskia at gcc dot gnu.org
  2024-05-10  6:15 ` [Bug c/115023] " pinskia at gcc dot gnu.org
@ 2024-05-10 12:37 ` rguenth at gcc dot gnu.org
  1 sibling, 0 replies; 3+ messages in thread
From: rguenth at gcc dot gnu.org @ 2024-05-10 12:37 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115023

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
It's supposed to behave like parens in the Fortran standard, maybe they have
good wording.

^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-05-10 12:37 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2024-05-10  6:15 [Bug c/115023] New: __builtin_assoc_barrier does not talk about contracting even though it prevents it too pinskia at gcc dot gnu.org
2024-05-10  6:15 ` [Bug c/115023] " pinskia at gcc dot gnu.org
2024-05-10 12:37 ` rguenth at gcc dot gnu.org

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