[PATCH] D132975: [CMake] Add clang-bolt target

[Amir Ayupov via Phabricator via cfe-commits]

Amir marked an inline comment as done.
Amir added inline comments.


================
Comment at: clang/CMakeLists.txt:930-937
+                -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
+                -DCMAKE_C_COMPILER=${CLANG_INSTRUMENTED}
+                -DCMAKE_CXX_COMPILER=${CLANGXX_INSTRUMENTED}
+                -DCMAKE_ASM_COMPILER=${CLANG_INSTRUMENTED}
+                -DCMAKE_ASM_COMPILER_ID=Clang
+                -DCMAKE_BUILD_TYPE=Release
+                -DLLVM_ENABLE_PROJECTS=${CLANG_BOLT_INSTRUMENT_PROJECTS}
----------------
Amir wrote:
> MaskRay wrote:
> > phosek wrote:
> > > I don't think this is sufficient in the general case, we would need to pass additional variables like `CMAKE_AR` the same way we do for the existing bootstrap logic, see https://github.com/llvm/llvm-project/blob/dc549bf0013e11e8fcccba8a8d59c3a4bb052a3b/clang/CMakeLists.txt#L825.
> > > 
> > > For example, on Fuchsia builders we don't have any system-wide toolchain installation, instead we manually set  all necessary `CMAKE_<TOOL>` variables for the first stage, so this call will fail for us because it won't be able to find tools like the archiver.
> > > 
> > > Since handling this properly would likely duplicate a lot of the existing logic from the existing bootstrap logic, I'm wondering if we should instead try to refactor the existing logic and break it up into macros/functions which could then be reused here as well.
> > Supporting other cmake variables will be awesome. I use something like `-DCMAKE_CXX_ARCHIVE_CREATE="$HOME/llvm/out/stable/bin/llvm-ar qcS --thin <TARGET> <OBJECTS>" -DCMAKE_CXX_ARCHIVE_FINISH=:` to make my build smaller.
> Addressed in D133633
Done: -DCLANG_BOLT_INSTRUMENT_EXTRA_CMAKE_FLAGS is passed to the cmake step of bolt-instrumentation-profile target.
I tested it with 
```
-DCLANG_BOLT_INSTRUMENT_EXTRA_CMAKE_FLAGS='-DCMAKE_CXX_ARCHIVE_CREATE="<path/to/llvm/bin>/llvm-ar qcS --thin <TARGET> <OBJECTS>" -DCMAKE_CXX_ARCHIVE_FINISH=:'
```
and that appeared to work.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D132975/new/

https://reviews.llvm.org/D132975