openmp/CMakeLists.txt

cmake_minimum_required(VERSION 3.20.0)
set(LLVM_SUBPROJECT_TITLE "OpenMP")

set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)

# Add path for custom modules
list(INSERT CMAKE_MODULE_PATH 0
  "${CMAKE_CURRENT_SOURCE_DIR}/cmake"
  "${LLVM_COMMON_CMAKE_UTILS}/Modules"
  )

# llvm/runtimes/ will set OPENMP_STANDALONE_BUILD.
if (OPENMP_STANDALONE_BUILD OR "${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}")
  set(OPENMP_STANDALONE_BUILD TRUE)
  project(openmp C CXX ASM)
else()
  set(OPENMP_STANDALONE_BUILD FALSE)
endif()

# Must go below project(..)
include(GNUInstallDirs)

if (OPENMP_STANDALONE_BUILD)
  set(LLVM_TREE_AVAILABLE False)

  # CMAKE_BUILD_TYPE was not set, default to Release.
  if (NOT CMAKE_BUILD_TYPE)
    set(CMAKE_BUILD_TYPE Release)
  endif()

  # Group common settings.
  set(OPENMP_ENABLE_WERROR FALSE CACHE BOOL
    "Enable -Werror flags to turn warnings into errors for supporting compilers.")
  set(OPENMP_LIBDIR_SUFFIX "" CACHE STRING
    "Suffix of lib installation directory, e.g. 64 => lib64")
  # Do not use OPENMP_LIBDIR_SUFFIX directly, use OPENMP_INSTALL_LIBDIR.
  set(OPENMP_INSTALL_LIBDIR "lib${OPENMP_LIBDIR_SUFFIX}" CACHE STRING
      "Path where built OpenMP libraries should be installed.")

  # Group test settings.
  set(OPENMP_TEST_C_COMPILER ${CMAKE_C_COMPILER} CACHE STRING
    "C compiler to use for testing OpenMP runtime libraries.")
  set(OPENMP_TEST_CXX_COMPILER ${CMAKE_CXX_COMPILER} CACHE STRING
    "C++ compiler to use for testing OpenMP runtime libraries.")
  set(OPENMP_TEST_Fortran_COMPILER ${CMAKE_Fortran_COMPILER} CACHE STRING
    "FORTRAN compiler to use for testing OpenMP runtime libraries.")
  set(OPENMP_LLVM_TOOLS_DIR "" CACHE PATH "Path to LLVM tools for testing.")

  set(CMAKE_CXX_STANDARD 17 CACHE STRING "C++ standard to conform to")
  set(CMAKE_CXX_STANDARD_REQUIRED NO)
  set(CMAKE_CXX_EXTENSIONS NO)
else()
  # Usually <llvm-project>/runtimes/CMakeLists.txt sets LLVM_TREE_AVAILABLE and
  # we assume it is not available otherwise. The exception is that we are in an
  # LLVM_ENABLE_PROJECTS=openmp build, the LLVM tree is actually available.
  # Note that this build mode has been deprecated.
  # See https://github.com/llvm/llvm-project/issues/124014
  if (NOT LLVM_RUNTIMES_BUILD AND "openmp" IN_LIST LLVM_ENABLE_PROJECTS)
    set(LLVM_TREE_AVAILABLE True)
  endif ()

  set(OPENMP_ENABLE_WERROR ${LLVM_ENABLE_WERROR})

  # When building in tree we install the runtime according to the LLVM settings.
  if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
    set(OPENMP_INSTALL_LIBDIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE STRING
        "Path where built openmp libraries should be installed.")
  else()
    set(OPENMP_INSTALL_LIBDIR "lib${LLVM_LIBDIR_SUFFIX}" CACHE STRING
        "Path where built OpenMP libraries should be installed.")
  endif()

  if (NOT MSVC)
    set(OPENMP_TEST_C_COMPILER ${LLVM_RUNTIME_OUTPUT_INTDIR}/clang)
    set(OPENMP_TEST_CXX_COMPILER ${LLVM_RUNTIME_OUTPUT_INTDIR}/clang++)
  else()
    set(OPENMP_TEST_C_COMPILER ${LLVM_RUNTIME_OUTPUT_INTDIR}/clang.exe)
    set(OPENMP_TEST_CXX_COMPILER ${LLVM_RUNTIME_OUTPUT_INTDIR}/clang++.exe)
  endif()

  # Check for flang
  if (NOT MSVC)
    set(OPENMP_TEST_Fortran_COMPILER ${LLVM_RUNTIME_OUTPUT_INTDIR}/flang)
  else()
    set(OPENMP_TEST_Fortran_COMPILER ${LLVM_RUNTIME_OUTPUT_INTDIR}/flang.exe)
  endif()

  # Set fortran test compiler if flang is found
  if (EXISTS "${OPENMP_TEST_Fortran_COMPILER}")
    message("Using local flang build at ${OPENMP_TEST_Fortran_COMPILER}")
  else()
    unset(OPENMP_TEST_Fortran_COMPILER)
  endif()

  # If not standalone, set CMAKE_CXX_STANDARD but don't set the global cache value,
  # only set it locally for OpenMP.
  set(CMAKE_CXX_STANDARD 17)
  set(CMAKE_CXX_STANDARD_REQUIRED NO)
  set(CMAKE_CXX_EXTENSIONS NO)
endif()

# Targeting the GPU directly requires a few flags to make CMake happy.
if("${CMAKE_CXX_COMPILER_TARGET}" MATCHES "^amdgcn")
  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nogpulib")
elseif("${CMAKE_CXX_COMPILER_TARGET}" MATCHES "^nvptx")
  set(CMAKE_REQUIRED_FLAGS
      "${CMAKE_REQUIRED_FLAGS} -flto -c -Wno-unused-command-line-argument")
endif()

# Check and set up common compiler flags.
include(config-ix)
include(HandleOpenMPOptions)

# Set up testing infrastructure.
include(OpenMPTesting)

set(OPENMP_TEST_FLAGS "" CACHE STRING
  "Extra compiler flags to send to the test compiler.")
set(OPENMP_TEST_OPENMP_FLAGS ${OPENMP_TEST_COMPILER_OPENMP_FLAGS} CACHE STRING
  "OpenMP compiler flag to use for testing OpenMP runtime libraries.")

set(ENABLE_LIBOMPTARGET ON)
# Currently libomptarget cannot be compiled on Windows or MacOS X.
# Since the device plugins are only supported on Linux anyway,
# there is no point in trying to compile libomptarget on other OSes.
# 32-bit systems are not supported either.
if (APPLE OR WIN32 OR WASM OR NOT "cxx_std_17" IN_LIST CMAKE_CXX_COMPILE_FEATURES
    OR NOT CMAKE_SIZEOF_VOID_P EQUAL 8 OR "${CMAKE_SYSTEM_NAME}" MATCHES "AIX")
  set(ENABLE_LIBOMPTARGET OFF)
endif()

option(OPENMP_ENABLE_LIBOMPTARGET "Enable building libomptarget for offloading."
       ${ENABLE_LIBOMPTARGET})
option(OPENMP_ENABLE_LIBOMP_PROFILING "Enable time profiling for libomp." OFF)

# Header install location
if(NOT LLVM_TREE_AVAILABLE)
  set(LIBOMP_HEADERS_INSTALL_PATH "${CMAKE_INSTALL_INCLUDEDIR}")
else()
  include(GetClangResourceDir)
  get_clang_resource_dir(LIBOMP_HEADERS_INSTALL_PATH SUBDIR include)
endif()

# Use the current compiler target to determine the appropriate runtime to build.
if("${LLVM_DEFAULT_TARGET_TRIPLE}" MATCHES "^amdgcn|^nvptx" OR
   "${CMAKE_CXX_COMPILER_TARGET}" MATCHES "^amdgcn|^nvptx")
  add_subdirectory(device)
else()
  # Build host runtime library, after LIBOMPTARGET variables are set since they
  # are needed to enable time profiling support in the OpenMP runtime.
  add_subdirectory(runtime)

  set(ENABLE_OMPT_TOOLS ON)
  # Currently tools are not tested well on Windows or MacOS X.
  if (APPLE OR WIN32)
    set(ENABLE_OMPT_TOOLS OFF)
  endif()

  option(OPENMP_ENABLE_OMPT_TOOLS "Enable building ompt based tools for OpenMP."
         ${ENABLE_OMPT_TOOLS})
  if (OPENMP_ENABLE_OMPT_TOOLS)
    add_subdirectory(tools)
  endif()

  # Propagate OMPT support to offload
  if(NOT ${OPENMP_STANDALONE_BUILD})
    set(LIBOMP_HAVE_OMPT_SUPPORT ${LIBOMP_HAVE_OMPT_SUPPORT} PARENT_SCOPE)
    set(LIBOMP_OMP_TOOLS_INCLUDE_DIR ${LIBOMP_OMP_TOOLS_INCLUDE_DIR} PARENT_SCOPE)
  endif()

  option(OPENMP_MSVC_NAME_SCHEME "Build dll with MSVC naming scheme." OFF)

  # Build libompd.so
  add_subdirectory(libompd)

  # Build documentation
  add_subdirectory(docs)

  # Now that we have seen all testsuites, create the check-openmp target.
  construct_check_openmp_target()
endif()