dblaikie added a comment. > And another problem here is, without LTO, the function definitions in other > TU can't be inlined. But now, the function definitions in the module > interface can be imported to the importee as AvaialableExternally linkage > with optimization. The AvaialableExternally linkage is a special linkage > which aims for the IPO. And the AvaialableExternally entities would be > removed in the middle end after inlining. (I know there are arguments to > remove the function definition in the module file.) So if we move not > directly used things in .cpp files, the performance will be hurt. But it is > not the case for modules (at least for now).
Yeah, I think if we're planning to minimize pcms to the point where they can't do code generation I guess we'll probably remove the indirect function definitions/not use available externally, and rely on (Thin)LTO to provide whole program optimization - so the guidance that modules reduces link time wouldn't be true in that case. I think it's probably best to abandon this patch/not document/suggest that this is a benefit people should expect from modules if it's one that'd go away in the future anyway. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D138552/new/ https://reviews.llvm.org/D138552 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
