[PATCH] D82994: [RFC] Instrumenting Clang/LLVM with Perfetto

Thu Jul 16 13:41:10 PDT 2020

nickdesaulniers added inline comments.
Herald added a subscriber: dang.

================
Comment at: clang/lib/Driver/Driver.cpp:3754

+  // We don't need to count the assembler as a job since it doesn't
+  // cause the memory issue that requires disabling integrated-cc1.
----------------
lebedev.ri wrote:
> This appears unrelated to the patch.
This might be related to the requirement that perfetto trace everything in process; though I think this is also a pre-existing bug IMO that can be precommitted.

================
Comment at: llvm/cmake/modules/AddPerfetto.cmake:9
+  ExternalProject_Add(perfetto_git
+      GIT_REPOSITORY https://github.com/google/perfetto.git
+      GIT_TAG releases/v4.x
----------------
lebedev.ri wrote:
> I have concerns about this.
> It really should use system-provided version via `find_package()`
> At worst, the sources should be bundled into the tree like it's already done in some rare cases.
Not that I'm very good with CMake, but this seems to suggest that `ExternalProject_Add` may not compose well with `find_package`: https://stackoverflow.com/questions/6351609/cmake-linking-to-library-downloaded-from-externalproject-add

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D82994/new/

https://reviews.llvm.org/D82994