Stream: t-compiler/wg-llvm

Topic: new pass manager


cuviper (Sep 10 2019 at 17:35, on Zulip):

Is anyone already working on the new pass manager? https://github.com/rust-lang/rust/issues/64289
If not, I would be interested to try this myself

Nikita Popov (Sep 10 2019 at 21:47, on Zulip):

Nope, not aware of anyone working on newpm yet. Feel free :)

Nikita Popov (Oct 02 2019 at 21:12, on Zulip):

Did you have any luck with newpm?

cuviper (Oct 03 2019 at 16:56, on Zulip):

I started poking at it a little, mostly to learn how the new bits work, nothing to run yet

cuviper (Oct 03 2019 at 16:56, on Zulip):

unfortunately I got sidetracked with other work

mw (Oct 07 2019 at 13:43, on Zulip):

Looking forward to seeing this in action. Apparently the new pass manager can improve optimization quality: https://groups.google.com/d/msg/llvm-dev/CZmUJC4gMjQ/004NTMEYBAAJ

cuviper (Oct 28 2019 at 17:48, on Zulip):

FYI this is still on my mind, but personal life has been intense lately

Vadim Petrochenkov (Jan 08 2020 at 11:09, on Zulip):

I's there any summary on how the new pass manager is different from the old one and why?
I know the new pass manager was a multi-year effort, but I used only the most basic functionality in the old pass manager myself, so I find it hard to imagine why it would be such a big deal.

Nikita Popov (Jan 08 2020 at 13:07, on Zulip):

I'm not really familiar either, but I believe the main difference and advantage is in how it manages analysis passes.

Nikita Popov (Jan 08 2020 at 13:08, on Zulip):

I believe those get computed more lazily now and also get invalidated more lazily (e.g. if a transform pass doesn't make any changes, even if it does not explicitly preserve some specific analysis.)

Nikita Popov (Jan 08 2020 at 13:09, on Zulip):

And apparently some kinds of analysis couldn't be accessed in some types of transformation passes before ... or something.

Last update: Jan 23 2020 at 23:00UTC