[llvm-dev] [RFC] Deprecating the legacy pass manager for the optimization pipeline

[Florian Hahn via llvm-dev]

> On 31 Aug 2021, at 23:34, Arthur Eubanks via llvm-dev <llvm-dev at lists.llvm.org> wrote:
> 
> Debugging new PM regressions is reasonable. I thought people were just taking too long to port passes. Given that argument I'm content to wait until the next branch.
> 
> We can start migrating lit tests as you say.


FWIW I think it makes sense to delay removing legacy PM code by six months, start moving lit tests now and also not require to investigate/fix legacy PM-only issues.

But I think it would be good to spell out the decision somewhere; maybe add a note that legacy PM support is due to be removed after the 14.0 release in the release notes on the 13.x and main branches? IMO that could be considered sufficient notice and we won’t be back to discussing whether to go ahead with the removal in 6 months again.

Cheers,
Florian