yurai007 added a comment. In D120334#3338367 <https://reviews.llvm.org/D120334#3338367>, @jansvoboda11 wrote:
> In D120334#3338314 <https://reviews.llvm.org/D120334#3338314>, @yurai007 > wrote: > >> In D120334#3337961 <https://reviews.llvm.org/D120334#3337961>, @jansvoboda11 >> wrote: >> >>> The performance implications are pretty interesting! Have you tried >>> avoiding the copy altogether by just storing the reference? >> >> Yes, actually that was my first attempt but I failed miserably. >> LangOpts::LineComment is mutated in Lexer so LangOpts cannot be simply >> const&. Making it non-const reference is technically doable with some extra >> adjustment for Lexer constructors. >> However I'm worried a bit how it would impact external LangOpts users after >> mutating LineComment member by Lexer. As long as LangOpts acts as simple >> cache it's easy to reason about but when we start to share it with Lexer >> callers I'm not longer sure. That's why eventually base class approach was >> chosen. > > Got it. It seems like getting rid of the `LineComment` mutation would be > pretty straightforward though. I don't expect any big perf win by replacing > copy of a handful of bitfields with indirection, but it would be interesting > to see the experiment nonetheless. Ok. I can explore more this direction and come back with results. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D120334/new/ https://reviews.llvm.org/D120334 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
