sugak added subscribers: weiwang, sugak. sugak added a comment. Herald added a subscriber: sstefan1.
Hi @yaxunl! I'm working on upgrading a large codebase from LLVM-9 to LLVM-12. I noticed on average 10% compilation speed regression that seems to be caused this change. We use Clang modules and historically provide `-fopenmp` compiler flag by default. The problem seem to be that compiling and importing modules is now slower, with the generated modules size increased by 2X. llvm-bcanalyzer tool shows that it's dominated by `DECLS_TO_CHECK_FOR_DEFERRED_DIAGS`. If I understand it right, your change is only relevant when target offloading is used. I inspected all of `#pragma omp` directives and can confirm that we don't use it. I see that most of this code is gated by OpenMP flag. I wonder if there is a finer grain way to enable openmp parallel code generation without target offloading? Would it make sense to extend this code to check if `-fopenom-targets` is set before recording `DECLS_TO_CHECK_FOR_DEFERRED_DIAGS`? Note, this was measured @weiwang's https://reviews.llvm.org/D101793. CHANGES SINCE LAST ACTION https://reviews.llvm.org/D70172/new/ https://reviews.llvm.org/D70172 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
