[llvm] r348944 - [Unroll/UnrollAndJam/Vectorizer/Distribute] Add followup loop attributes.

[Michael Kruse via llvm-commits]

Am Do., 13. Dez. 2018 um 18:18 Uhr schrieb Jordan Rupprecht
<rupprecht at google.com>:
> Thanks for taking a look -- I don't see "Can't unroll" when I run it on the real test case I have, but I do see:
> Loop Unroll: F[<method name>] Loop %for.body
>   Loop Size = 16
>   partially unrolling with count: 1
> And it looks like a count of 1 gets treated similarly to disabling loop unrolling.

Correct.
If there is !{!"llvm.loop.unroll.count", i32 1} it should also not
give a warning message.
It could also have determined that unrolling by a factor of '1' is the
most profitable, i.e. it considered unrolling unprofitable.

> The bitcode is identical in this case as well. (Attaching a better creduced test case that demonstrates this).
>
> I guess I have a cleanup to do to remove a bunch of unnecessary pragmas! Is there a simple way to (temporarily) disable this warning? My naive attempt of -Wno-pass-failed=transform-warning doesn't seem to be accepted.

Did you try -Wno-pass-failed ? It seems that it does not support
taking an option. You could submit a bug report.

Michael