[PATCH] D78950: Adds LRU caching of compile units in DWARFContext.

[Pavel Labath via Phabricator via llvm-commits]

labath added a comment.

First off, let me say that I don't feel qualified to set the direction here, nor I am fully familiar with all of these interfaces. However, since I am already involved in here, I am going to say something anyway. :)

The way I would imagine this working ideally is that there would be two layers. The lower layer would provide more explicit access to the debug info, and it would provide it's users with the ability to manually manage the memory usage. It would be the responsibility of the users to not shoot themselves in the foot if they use it.

The second layer would offer a higher level view of the debug info and it would manage the memory (semi)automatically. Being high level it would/could/should also abstract away the difference between the different debug info formats.

The first layer would roughly correspond to the current DWARFUnit, DWARFContext, etc. classes, with one important difference DWARFContext would not implement DIContext -- it would be a standalone class. The second layer would correspond to the DIContext class, and any of the (new) helper classes it needs to manage the memory and perform the abstractions.

The main advantage I see in that is the breaking of the is-a relationship between DWARFContext and DIContext. Without it the interfaces seems rather shoot-footy because one can happily play around with the lower-level DWARFContext apis (which don't manage memory), and then accidentally call some higher level method which comes from DIContext , which does the management and will then cause the debug info to disappear from under you.

As I said, I don't know how easy would be to reach this state, nor whether it would be an acceptable state for other stakeholders...


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D78950/new/

https://reviews.llvm.org/D78950