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

if(DEFINED LIBOMP_SHARED_LINKER_FLAGS)
  set(CMAKE_SHARED_LINKER_FLAGS "${LIBOMP_SHARED_LINKER_FLAGS}")
endif()

if(DEFINED LIBOMP_INSTALL_RPATH)
  set(CMAKE_INSTALL_RPATH "${LIBOMP_INSTALL_RPATH}")
endif()

# Add cmake directory to search for custom cmake functions.
#set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake ${CMAKE_MODULE_PATH})
set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
include(${LLVM_COMMON_CMAKE_UTILS}/Modules/CMakePolicy.cmake
  NO_POLICY_SCOPE)

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

if (OPENMP_STANDALONE_BUILD OR "${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}")
  message(FATAL_ERROR [[The legacy standalone build mode has been removed. Please change
    cmake <llvm-project>/openmp
to
    cmake <llvm-project>/runtimes -DLLVM_ENABLE_RUNTIMES=openmp
For more details on building the LLVM OpenMP libraries, see https://openmp.llvm.org/Building.html]])
endif()

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

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.
# TODO: Use common runtimes infrastructure for output and install paths
if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
  set(OPENMP_TARGET_SUBDIR "${LLVM_DEFAULT_TARGET_TRIPLE}")
  if(OPENMP_LIBDIR_SUBDIR)
    string(APPEND OPENMP_TARGET_SUBDIR "/${OPENMP_LIBDIR_SUBDIR}")
  endif()
  cmake_path(NORMAL_PATH OPENMP_TARGET_SUBDIR)
  set(OPENMP_INSTALL_LIBDIR "lib${LLVM_LIBDIR_SUFFIX}/${OPENMP_TARGET_SUBDIR}" 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()

set(OPENMP_INSTALL_CFGDIR "lib/cmake" CACHE STRING
      "Path where OpenMP config should be installed")

set(OPENMP_TEST_C_COMPILER_default "${LLVM_TOOLS_BINARY_DIR}/clang${CMAKE_EXECUTABLE_SUFFIX}")
set(OPENMP_TEST_CXX_COMPILER_default "${LLVM_TOOLS_BINARY_DIR}/clang++${CMAKE_EXECUTABLE_SUFFIX}")
set(OPENMP_TEST_Fortran_COMPILER_default "${LLVM_TOOLS_BINARY_DIR}/flang${CMAKE_EXECUTABLE_SUFFIX}")
if (NOT TARGET "clang")
  set(OPENMP_TEST_C_COMPILER_default "${CMAKE_C_COMPILER}")
  set(OPENMP_TEST_CXX_COMPILER_default "${CMAKE_CXX_COMPILER}")
endif()
if (NOT TARGET "flang")
  if (CMAKE_Fortran_COMPILER)
    set(OPENMP_TEST_Fortran_COMPILER_default "${CMAKE_Fortran_COMPILER}")
  else()
    unset(OPENMP_TEST_Fortran_COMPILER_default)
  endif()
endif()
set(OPENMP_TEST_C_COMPILER "${OPENMP_TEST_C_COMPILER_default}" CACHE STRING
  "C compiler to use for testing OpenMP runtime libraries.")
set(OPENMP_TEST_CXX_COMPILER "${OPENMP_TEST_CXX_COMPILER_default}" CACHE STRING
  "C++ compiler to use for testing OpenMP runtime libraries.")
set(OPENMP_TEST_Fortran_COMPILER "${OPENMP_TEST_Fortran_COMPILER_default}" CACHE STRING
  "Fortran compiler to use for testing OpenMP runtime libraries.")

# 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)

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


# Set libomp version
set(LIBOMP_VERSION_MAJOR 5)
set(LIBOMP_VERSION_MINOR 0)

# Set the OpenMP Year and Month associated with version
set(LIBOMP_OMP_YEAR_MONTH 201611)

# Get the build number from kmp_version.cpp
libomp_get_build_number("${CMAKE_CURRENT_SOURCE_DIR}/runtime" LIBOMP_VERSION_BUILD)
math(EXPR LIBOMP_VERSION_BUILD_YEAR "${LIBOMP_VERSION_BUILD}/10000")
math(EXPR LIBOMP_VERSION_BUILD_MONTH_DAY "${LIBOMP_VERSION_BUILD}%10000")

# Currently don't record any timestamps
set(LIBOMP_BUILD_DATE "No_Timestamp")


set(LIBOMP_FORTRAN_MODULES FALSE CACHE BOOL
  "Create Fortran module files? (requires fortran compiler)")

option(LIBOMP_FORTRAN_MODULES_ONLY
  "Build only Fortran modules without libomp runtime library" OFF)
if(LIBOMP_FORTRAN_MODULES_ONLY)
  set(LIBOMP_FORTRAN_MODULES TRUE)
endif()

# 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()

# Meta-target for building OpenMP runtime artifacts (libraries, device RTL, tools).
# Subdirectories call openmp_register_meta_dep() for each target they add.
add_custom_target(openmp ALL
  COMMENT "OpenMP meta-target. Use 'ninja openmp' to build all OpenMP runtime targets."
)

add_custom_target(install-openmp
  COMMAND "${CMAKE_COMMAND}" --install "${CMAKE_BINARY_DIR}" --component openmp)
add_custom_target(install-openmp-stripped
  COMMAND "${CMAKE_COMMAND}" --install "${CMAKE_BINARY_DIR}" --component openmp --strip)
add_dependencies(install-openmp openmp)
add_dependencies(install-openmp-stripped openmp)

# Use the current compiler target to determine the appropriate runtime to build.
if("${LLVM_DEFAULT_TARGET_TRIPLE}" MATCHES "^amdgcn|^nvptx|^spirv64" OR
   "${CMAKE_CXX_COMPILER_TARGET}" MATCHES "^amdgcn|^nvptx|^spirv64")
  add_subdirectory(device)
else()
  add_subdirectory(module)

  # Build host runtime library, after LIBOMPTARGET variables are set since they
  # are needed to enable time profiling support in the OpenMP runtime.
  if(NOT LIBOMP_FORTRAN_MODULES_ONLY)
    add_subdirectory(runtime)
  endif()	

  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
  set(LIBOMP_HAVE_OMPT_SUPPORT ${LIBOMP_HAVE_OMPT_SUPPORT} PARENT_SCOPE)
  set(LIBOMP_OMP_TOOLS_INCLUDE_DIR ${LIBOMP_OMP_TOOLS_INCLUDE_DIR} PARENT_SCOPE)

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

  # Build libompd.so
  add_subdirectory(libompd)

  # Build documentation
  add_subdirectory(docs)
endif()

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