[Openmp-commits] [compiler-rt] [libc] [libcxx] [libcxxabi] [libunwind] [llvm] [openmp] [Runtimes] Introduce variables containing resource dir paths (PR #177953)

[Michael Kruse via Openmp-commits]

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@@ -236,6 +237,36 @@ if(CMAKE_C_COMPILER_ID MATCHES "Clang")
   endif()
 endif()
 
+# Determine output and install paths based on LLVM_TARGET_TRIPLE
+if(LLVM_TREE_AVAILABLE)
+  # Despite Clang in the name, get_clang_resource_dir does not depend on Clang
+  # being added to the build. Flang uses the same resource dir as Clang.
+  include(GetClangResourceDir)
+  get_clang_resource_dir(RUNTIMES_OUTPUT_RESOURCE_DIR PREFIX "${LLVM_LIBRARY_OUTPUT_INTDIR}/..")
+  get_clang_resource_dir(RUNTIMES_INSTALL_RESOURCE_PATH_DEFAULT)
+else()
+  # For the install prefix, still use the resource dir assuming the compilers
+  # looking for it (Clang, Flang) will be installed there using the same prefix.
+  # This is to not have a difference between bootstrapping and default/standalone runtimes
+  # builds.
+  set(RUNTIMES_OUTPUT_RESOURCE_DIR "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/clang/${LLVM_VERSION_MAJOR}")
+  set(RUNTIMES_INSTALL_RESOURCE_PATH_DEFAULT "lib${LLVM_LIBDIR_SUFFIX}/clang/${LLVM_VERSION_MAJOR}")
+endif()
+
+# Determine build and install paths. The output paths are absolute, but the
+# install dirs are relative to CMAKE_INSTALL_PREFIX to be resolved by CMake.
+get_toolchain_library_subdir(toolchain_lib_subdir)
+extend_path(RUNTIMES_OUTPUT_RESOURCE_LIB_DIR "${RUNTIMES_OUTPUT_RESOURCE_DIR}" "${toolchain_lib_subdir}")
+
+set(RUNTIMES_INSTALL_RESOURCE_PATH "${RUNTIMES_INSTALL_RESOURCE_PATH_DEFAULT}" CACHE PATH "Path to install headers, runtime libraries, and Fortran modules to (default: Clang resource dir)")
+extend_path(RUNTIMES_INSTALL_RESOURCE_LIB_PATH "${RUNTIMES_INSTALL_RESOURCE_PATH}" "${toolchain_lib_subdir}")
----------------
Meinersbur wrote:

I considered it a compiler-rt specific option. It's description says "Build builtins only for the default target", i.e. as it it only applies to clang_rt.builtins. From that description, I could not see any relation to triples. Looking at llvm/runtimes/CMakeLists.txt, it seems to NOT be set for the (non-builtin) default target.

So you are saying I should introduce `RUNTIMES_DEFAULT_TARGET_ONLY` which switches off triple normalization for (all?) other runtimes as well?



https://github.com/llvm/llvm-project/pull/177953