[pstl] Initial integration with LLVM's CMake

[ldionne]

Summary

This commit adds a check-pstl CMake target that will run the tests
we currently have for pstl. Those tests are not using LLVM lit yet,
but switching them over should be a transparent change. With this
change, we can start relying on the check-pstl target for workflows
and CI.

Note that this commit purposefully does not support the pre-monorepo
layout (with subprojects in projects/), since LLVM is moving towards
the monorepo layout anyway.

[ldionne]

pstl/cmake/FindTBB.cmake

12

This is required because otherwise they look for both the release and the Debug version of TBB, and we don't find anything if both are not provided. The rest of FindTBB.cmake handles this properly, so I'm not sure why they even try to defer to the TBBConfig.cmake.

[MikeDvorskiy]

pstl/cmake/FindTBB.cmake

12

Yes, the changes may be accepted, at least till the TBBConfig.cmake will not require both Release and Debug TBB.

[ldionne]

@jfb is on vacation, going forward. This is really more for exposition than anything anyway, since this is to get some testing going.

pstl/cmake/FindTBB.cmake

12

Please consider chiming in here: https://github.com/01org/tbb/issues/113

llvm/projects/CMakeLists.txt

if(${LLVM_BUILD_RUNTIME})
   # fixed.
   # FIXME: LLVM_FORCE_BUILD_RUNTIME is currently used by libc++ to force
   # enable the in-tree build when targeting clang-cl.
   if(NOT MSVC OR LLVM_FORCE_BUILD_RUNTIME)
     # Add the projects in reverse order of their dependencies so that the
     # dependent projects can see the target names of their dependencies.
     add_llvm_external_project(libunwind)
     add_llvm_external_project(libcxxabi)
+    add_llvm_external_project(pstl)
     add_llvm_external_project(libcxx)
   endif()
   if(NOT LLVM_BUILD_EXTERNAL_COMPILER_RT)
     add_llvm_external_project(compiler-rt)
   endif()
 endif()
 
 add_llvm_external_project(dragonegg)
 add_llvm_external_project(parallel-libs)
 add_llvm_external_project(openmp)
 
 if(LLVM_INCLUDE_TESTS)
   add_llvm_external_project(debuginfo-tests)
 endif()

pstl/CMakeLists.txt

 #===-- CMakeLists.txt ----------------------------------------------------===##
 #
 #                     The LLVM Compiler Infrastructure
 #
 # This file is dual licensed under the MIT and the University of Illinois Open
 # Source Licenses. See LICENSE.TXT for details.
 #
 #===----------------------------------------------------------------------===##
+cmake_minimum_required(VERSION 3.4.3)
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 
-cmake_minimum_required(VERSION 3.1)
-
-set(PARALLELSTL_VERSION_FILE "include/pstl/internal/pstl_config.h")
+set(PARALLELSTL_VERSION_FILE "${CMAKE_CURRENT_SOURCE_DIR}/include/pstl/internal/pstl_config.h")
 file(STRINGS "${PARALLELSTL_VERSION_FILE}" PARALLELSTL_VERSION_SOURCE REGEX "#define PSTL_VERSION .*$")
 string(REGEX MATCH "#define PSTL_VERSION (.*)$" PARALLELSTL_VERSION_SOURCE "${PARALLELSTL_VERSION_SOURCE}")
 math(EXPR VERSION_MAJOR "${PARALLELSTL_VERSION_SOURCE} / 100")
 math(EXPR VERSION_MINOR "${PARALLELSTL_VERSION_SOURCE} % 100")
 
 project(ParallelSTL VERSION ${VERSION_MAJOR}.${VERSION_MINOR} LANGUAGES CXX)
 
 option(PARALLELSTL_USE_PARALLEL_POLICIES "Enable parallel policies" ON)
 set(PARALLELSTL_BACKEND "tbb" CACHE STRING "Threading backend; defaults to TBB")
 
 include(CMakePackageConfigHelpers)
 
 if (NOT TBB_DIR)
     get_filename_component(PSTL_DIR_NAME ${CMAKE_CURRENT_SOURCE_DIR} NAME)
     string(REPLACE pstl tbb TBB_DIR_NAME ${PSTL_DIR_NAME})
     if (EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/../${TBB_DIR_NAME}/cmake")
         get_filename_component(TBB_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../${TBB_DIR_NAME}/cmake" ABSOLUTE)
     endif()
 endif()
 
-set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
-
 add_library(ParallelSTL INTERFACE)
 add_library(pstl::ParallelSTL ALIAS ParallelSTL)
 
 if (PARALLELSTL_USE_PARALLEL_POLICIES)
     if (PARALLELSTL_BACKEND STREQUAL "tbb")
         find_package(TBB 2018 REQUIRED tbb OPTIONAL_COMPONENTS tbbmalloc)
         message(STATUS "Parallel STL uses TBB ${TBB_VERSION} (interface version: ${TBB_INTERFACE_VERSION})")
         target_link_libraries(ParallelSTL INTERFACE TBB::tbb)
     else()
         if (TARGET ${PARALLELSTL_BACKEND})
             target_link_libraries(ParallelSTL INTERFACE ${PARALLELSTL_BACKEND})
         else()
             find_package(${PARALLELSTL_BACKEND} REQUIRED)
             target_link_libraries(ParallelSTL INTERFACE ${${PARALLELSTL_BACKEND}_IMPORTED_TARGETS})
         endif()
     endif()
 else()
     target_add_definitions(ParallelSTL INTERFACE PSTL_USE_PARALLEL_POLICIES=0)
 endif()
 
 target_include_directories(ParallelSTL
     INTERFACE
-    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include/>
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
     $<INSTALL_INTERFACE:include>)
 
 write_basic_package_version_file(
     ${CMAKE_CURRENT_BINARY_DIR}/ParallelSTLConfigVersion.cmake
     VERSION ${PROJECT_VERSION}
     COMPATIBILITY AnyNewerVersion)
 
 configure_file(
     ParallelSTLConfig.cmake.in
     ${CMAKE_CURRENT_BINARY_DIR}/ParallelSTLConfig.cmake
     @ONLY)
 
 export(TARGETS ParallelSTL NAMESPACE pstl:: FILE ParallelSTLTargets.cmake)
 export(PACKAGE ParallelSTL)
+
+enable_testing()
+add_subdirectory(test)

pstl/cmake/FindTBB.cmake

 #===-- FindTBB.cmake -----------------------------------------------------===##
 #
 #                     The LLVM Compiler Infrastructure
 #
 # This file is dual licensed under the MIT and the University of Illinois Open
 # Source Licenses. See LICENSE.TXT for details.
 #
 #===----------------------------------------------------------------------===##
 
 include(FindPackageHandleStandardArgs)
 
-# Firstly search for TBB in config mode (i.e. search for TBBConfig.cmake).
-find_package(TBB QUIET CONFIG)
-if (TBB_FOUND)
-    find_package_handle_standard_args(TBB
-                                      REQUIRED_VARS TBB_IMPORTED_TARGETS
-                                      HANDLE_COMPONENTS
-                                      VERSION_VAR TBB_VERSION
-                                      CONFIG_MODE)
-    return()
-endif()
-
 if (NOT TBB_FIND_COMPONENTS)
     set(TBB_FIND_COMPONENTS tbb tbbmalloc)
     foreach (_tbb_component ${TBB_FIND_COMPONENTS})
         set(TBB_FIND_REQUIRED_${_tbb_component} 1)
     endforeach()
 endif()
 
 find_path(_tbb_include_dir tbb/tbb.h)

pstl/test/CMakeLists.txt

+#===-- CMakeLists.txt ----------------------------------------------------===##
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is dual licensed under the MIT and the University of Illinois Open
+# Source Licenses. See LICENSE.TXT for details.
+#
+#===----------------------------------------------------------------------===##
+
+# TODO(ldionne): This CMake testing infrastructure should be replaced with a
+#                llvm-lit test suite.
+
+add_custom_target(pstl-build-tests
+    COMMENT "Build all the pstl tests.")
+
+add_custom_target(check-pstl
+    COMMAND "${CMAKE_CTEST_COMMAND}" --output-on-failure
+    USES_TERMINAL
+    DEPENDS pstl-build-tests
+    COMMENT "Build and run all the unit tests.")
+
+file(GLOB_RECURSE UNIT_TESTS "test_*.cpp")
+foreach(_file IN LISTS UNIT_TESTS)
+    file(RELATIVE_PATH _target "${CMAKE_CURRENT_SOURCE_DIR}" "${_file}")
+    string(REPLACE ".cpp" "" _target "${_target}")
+    set(_target "pstl-${_target}")
+
+    add_executable(${_target} EXCLUDE_FROM_ALL "${_file}")
+    target_link_libraries(${_target} PRIVATE pstl::ParallelSTL)
+    set_target_properties(${_target} PROPERTIES CXX_EXTENSIONS NO
+                                                RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}")
+    add_test(${_target} "${CMAKE_CURRENT_BINARY_DIR}/${_target}")
+    add_dependencies(pstl-build-tests ${_target})
+endforeach()