[PATCH] D80765: [ELF] Handle bitcode comdat groups separately to deduplicate thinlto comdat sections

[David Blaikie via Phabricator via llvm-commits]

dblaikie added a comment.

Yeah - one alternative here would be for ThinLTO To "home" debug type information, the same way I believe it "homes" inline functions. (original/incoming IR to the thinlink may have multiple definitions of inline functions - one in every module that has a call to the inline function - but something in the think link summary basically says "drop this definition" in all but one of those modules and in that one blessed module it says "always produce a weak definition of this function, even if you don't need it" - something like that should be done with type information, which would remove the redundancy in the object files)

In the case of a full executable link, I'd then suggest not enabling type units, since they just add overhead and wouldn't reduce any duplication - in the case of a static library built with ThinLTO (if that's even a thing), then you'd still potentially want to use type units so they could be deduplicated against other libraries.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D80765/new/

https://reviews.llvm.org/D80765