Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/lib64/cmake/llvm/AddLLVM.cmake b/linux-x64/clang/lib64/cmake/llvm/AddLLVM.cmake
new file mode 100644
index 0000000..2f47010
--- /dev/null
+++ b/linux-x64/clang/lib64/cmake/llvm/AddLLVM.cmake
@@ -0,0 +1,1655 @@
+include(LLVMProcessSources)
+include(LLVM-Config)
+include(DetermineGCCCompatible)
+
+function(llvm_update_compile_flags name)
+  get_property(sources TARGET ${name} PROPERTY SOURCES)
+  if("${sources}" MATCHES "\\.c(;|$)")
+    set(update_src_props ON)
+  endif()
+
+  # LLVM_REQUIRES_EH is an internal flag that individual targets can use to
+  # force EH
+  if(LLVM_REQUIRES_EH OR LLVM_ENABLE_EH)
+    if(NOT (LLVM_REQUIRES_RTTI OR LLVM_ENABLE_RTTI))
+      message(AUTHOR_WARNING "Exception handling requires RTTI. Enabling RTTI for ${name}")
+      set(LLVM_REQUIRES_RTTI ON)
+    endif()
+    if(MSVC)
+      list(APPEND LLVM_COMPILE_FLAGS "/EHsc")
+    endif()
+  else()
+    if(LLVM_COMPILER_IS_GCC_COMPATIBLE)
+      list(APPEND LLVM_COMPILE_FLAGS "-fno-exceptions")
+    elseif(MSVC)
+      list(APPEND LLVM_COMPILE_DEFINITIONS _HAS_EXCEPTIONS=0)
+      list(APPEND LLVM_COMPILE_FLAGS "/EHs-c-")
+    endif()
+  endif()
+
+  # LLVM_REQUIRES_RTTI is an internal flag that individual
+  # targets can use to force RTTI
+  set(LLVM_CONFIG_HAS_RTTI YES CACHE INTERNAL "")
+  if(NOT (LLVM_REQUIRES_RTTI OR LLVM_ENABLE_RTTI))
+    set(LLVM_CONFIG_HAS_RTTI NO CACHE INTERNAL "")
+    list(APPEND LLVM_COMPILE_DEFINITIONS GTEST_HAS_RTTI=0)
+    if (LLVM_COMPILER_IS_GCC_COMPATIBLE)
+      list(APPEND LLVM_COMPILE_FLAGS "-fno-rtti")
+    elseif (MSVC)
+      list(APPEND LLVM_COMPILE_FLAGS "/GR-")
+    endif ()
+  elseif(MSVC)
+    list(APPEND LLVM_COMPILE_FLAGS "/GR")
+  endif()
+
+  # Assume that;
+  #   - LLVM_COMPILE_FLAGS is list.
+  #   - PROPERTY COMPILE_FLAGS is string.
+  string(REPLACE ";" " " target_compile_flags " ${LLVM_COMPILE_FLAGS}")
+
+  if(update_src_props)
+    foreach(fn ${sources})
+      get_filename_component(suf ${fn} EXT)
+      if("${suf}" STREQUAL ".cpp")
+        set_property(SOURCE ${fn} APPEND_STRING PROPERTY
+          COMPILE_FLAGS "${target_compile_flags}")
+      endif()
+    endforeach()
+  else()
+    # Update target props, since all sources are C++.
+    set_property(TARGET ${name} APPEND_STRING PROPERTY
+      COMPILE_FLAGS "${target_compile_flags}")
+  endif()
+
+  set_property(TARGET ${name} APPEND PROPERTY COMPILE_DEFINITIONS ${LLVM_COMPILE_DEFINITIONS})
+endfunction()
+
+function(add_llvm_symbol_exports target_name export_file)
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+    set(native_export_file "${target_name}.exports")
+    add_custom_command(OUTPUT ${native_export_file}
+      COMMAND sed -e "s/^/_/" < ${export_file} > ${native_export_file}
+      DEPENDS ${export_file}
+      VERBATIM
+      COMMENT "Creating export file for ${target_name}")
+    set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                 LINK_FLAGS " -Wl,-exported_symbols_list,${CMAKE_CURRENT_BINARY_DIR}/${native_export_file}")
+  elseif(${CMAKE_SYSTEM_NAME} MATCHES "AIX")
+    set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                 LINK_FLAGS " -Wl,-bE:${export_file}")
+  elseif(LLVM_HAVE_LINK_VERSION_SCRIPT)
+    # Gold and BFD ld require a version script rather than a plain list.
+    set(native_export_file "${target_name}.exports")
+    # FIXME: Don't write the "local:" line on OpenBSD.
+    # in the export file, also add a linker script to version LLVM symbols (form: LLVM_N.M)
+    add_custom_command(OUTPUT ${native_export_file}
+      COMMAND echo "LLVM_${LLVM_VERSION_MAJOR} {" > ${native_export_file}
+      COMMAND grep -q "[[:alnum:]]" ${export_file} && echo "  global:" >> ${native_export_file} || :
+      COMMAND sed -e "s/$/;/" -e "s/^/    /" < ${export_file} >> ${native_export_file}
+      COMMAND echo "  local: *;" >> ${native_export_file}
+      COMMAND echo "};" >> ${native_export_file}
+      DEPENDS ${export_file}
+      VERBATIM
+      COMMENT "Creating export file for ${target_name}")
+    if (${LLVM_LINKER_IS_SOLARISLD})
+      set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                   LINK_FLAGS "  -Wl,-M,${CMAKE_CURRENT_BINARY_DIR}/${native_export_file}")
+    else()
+      set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                   LINK_FLAGS "  -Wl,--version-script,${CMAKE_CURRENT_BINARY_DIR}/${native_export_file}")
+    endif()
+  else()
+    set(native_export_file "${target_name}.def")
+
+    add_custom_command(OUTPUT ${native_export_file}
+      COMMAND ${PYTHON_EXECUTABLE} -c "import sys;print(''.join(['EXPORTS\\n']+sys.stdin.readlines(),))"
+        < ${export_file} > ${native_export_file}
+      DEPENDS ${export_file}
+      VERBATIM
+      COMMENT "Creating export file for ${target_name}")
+    set(export_file_linker_flag "${CMAKE_CURRENT_BINARY_DIR}/${native_export_file}")
+    if(MSVC)
+      set(export_file_linker_flag "/DEF:\"${export_file_linker_flag}\"")
+    endif()
+    set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                 LINK_FLAGS " ${export_file_linker_flag}")
+  endif()
+
+  add_custom_target(${target_name}_exports DEPENDS ${native_export_file})
+  set_target_properties(${target_name}_exports PROPERTIES FOLDER "Misc")
+
+  get_property(srcs TARGET ${target_name} PROPERTY SOURCES)
+  foreach(src ${srcs})
+    get_filename_component(extension ${src} EXT)
+    if(extension STREQUAL ".cpp")
+      set(first_source_file ${src})
+      break()
+    endif()
+  endforeach()
+
+  # Force re-linking when the exports file changes. Actually, it
+  # forces recompilation of the source file. The LINK_DEPENDS target
+  # property only works for makefile-based generators.
+  # FIXME: This is not safe because this will create the same target
+  # ${native_export_file} in several different file:
+  # - One where we emitted ${target_name}_exports
+  # - One where we emitted the build command for the following object.
+  # set_property(SOURCE ${first_source_file} APPEND PROPERTY
+  #   OBJECT_DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/${native_export_file})
+
+  set_property(DIRECTORY APPEND
+    PROPERTY ADDITIONAL_MAKE_CLEAN_FILES ${native_export_file})
+
+  add_dependencies(${target_name} ${target_name}_exports)
+
+  # Add dependency to *_exports later -- CMake issue 14747
+  list(APPEND LLVM_COMMON_DEPENDS ${target_name}_exports)
+  set(LLVM_COMMON_DEPENDS ${LLVM_COMMON_DEPENDS} PARENT_SCOPE)
+endfunction(add_llvm_symbol_exports)
+
+if(NOT WIN32 AND NOT APPLE)
+  # Detect what linker we have here
+  if( LLVM_USE_LINKER )
+    set(command ${CMAKE_C_COMPILER} -fuse-ld=${LLVM_USE_LINKER} -Wl,--version)
+  else()
+    set(command ${CMAKE_C_COMPILER} -Wl,--version)
+  endif()
+  execute_process(
+    COMMAND ${command}
+    OUTPUT_VARIABLE stdout
+    ERROR_VARIABLE stderr
+    )
+  set(LLVM_LINKER_DETECTED ON)
+  if("${stdout}" MATCHES "GNU gold")
+    set(LLVM_LINKER_IS_GOLD ON)
+    message(STATUS "Linker detection: GNU Gold")
+  elseif("${stdout}" MATCHES "^LLD")
+    set(LLVM_LINKER_IS_LLD ON)
+    message(STATUS "Linker detection: LLD")
+  elseif("${stdout}" MATCHES "GNU ld")
+    set(LLVM_LINKER_IS_GNULD ON)
+    message(STATUS "Linker detection: GNU ld")
+  elseif("${stderr}" MATCHES "Solaris Link Editors" OR
+         "${stdout}" MATCHES "Solaris Link Editors")
+    set(LLVM_LINKER_IS_SOLARISLD ON)
+    message(STATUS "Linker detection: Solaris ld")
+  else()
+    set(LLVM_LINKER_DETECTED OFF)
+    message(STATUS "Linker detection: unknown")
+  endif()
+endif()
+
+function(add_link_opts target_name)
+  # Don't use linker optimizations in debug builds since it slows down the
+  # linker in a context where the optimizations are not important.
+  if (NOT uppercase_CMAKE_BUILD_TYPE STREQUAL "DEBUG")
+
+    # Pass -O3 to the linker. This enabled different optimizations on different
+    # linkers.
+    if(NOT (${CMAKE_SYSTEM_NAME} MATCHES "Darwin|SunOS|AIX" OR WIN32))
+      set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                   LINK_FLAGS " -Wl,-O3")
+    endif()
+
+    if(LLVM_LINKER_IS_GOLD)
+      # With gold gc-sections is always safe.
+      set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                   LINK_FLAGS " -Wl,--gc-sections")
+      # Note that there is a bug with -Wl,--icf=safe so it is not safe
+      # to enable. See https://sourceware.org/bugzilla/show_bug.cgi?id=17704.
+    endif()
+
+    if(NOT LLVM_NO_DEAD_STRIP)
+      if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+        # ld64's implementation of -dead_strip breaks tools that use plugins.
+        set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                     LINK_FLAGS " -Wl,-dead_strip")
+      elseif(${CMAKE_SYSTEM_NAME} MATCHES "SunOS")
+        set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                     LINK_FLAGS " -Wl,-z -Wl,discard-unused=sections")
+      elseif(NOT WIN32 AND NOT LLVM_LINKER_IS_GOLD)
+        # Object files are compiled with -ffunction-data-sections.
+        # Versions of bfd ld < 2.23.1 have a bug in --gc-sections that breaks
+        # tools that use plugins. Always pass --gc-sections once we require
+        # a newer linker.
+        set_property(TARGET ${target_name} APPEND_STRING PROPERTY
+                     LINK_FLAGS " -Wl,--gc-sections")
+      endif()
+    endif()
+  endif()
+endfunction(add_link_opts)
+
+# Set each output directory according to ${CMAKE_CONFIGURATION_TYPES}.
+# Note: Don't set variables CMAKE_*_OUTPUT_DIRECTORY any more,
+# or a certain builder, for eaxample, msbuild.exe, would be confused.
+function(set_output_directory target)
+  cmake_parse_arguments(ARG "" "BINARY_DIR;LIBRARY_DIR" "" ${ARGN})
+
+  # module_dir -- corresponding to LIBRARY_OUTPUT_DIRECTORY.
+  # It affects output of add_library(MODULE).
+  if(WIN32 OR CYGWIN)
+    # DLL platform
+    set(module_dir ${ARG_BINARY_DIR})
+  else()
+    set(module_dir ${ARG_LIBRARY_DIR})
+  endif()
+  if(NOT "${CMAKE_CFG_INTDIR}" STREQUAL ".")
+    foreach(build_mode ${CMAKE_CONFIGURATION_TYPES})
+      string(TOUPPER "${build_mode}" CONFIG_SUFFIX)
+      if(ARG_BINARY_DIR)
+        string(REPLACE ${CMAKE_CFG_INTDIR} ${build_mode} bi ${ARG_BINARY_DIR})
+        set_target_properties(${target} PROPERTIES "RUNTIME_OUTPUT_DIRECTORY_${CONFIG_SUFFIX}" ${bi})
+      endif()
+      if(ARG_LIBRARY_DIR)
+        string(REPLACE ${CMAKE_CFG_INTDIR} ${build_mode} li ${ARG_LIBRARY_DIR})
+        set_target_properties(${target} PROPERTIES "ARCHIVE_OUTPUT_DIRECTORY_${CONFIG_SUFFIX}" ${li})
+      endif()
+      if(module_dir)
+        string(REPLACE ${CMAKE_CFG_INTDIR} ${build_mode} mi ${module_dir})
+        set_target_properties(${target} PROPERTIES "LIBRARY_OUTPUT_DIRECTORY_${CONFIG_SUFFIX}" ${mi})
+      endif()
+    endforeach()
+  else()
+    if(ARG_BINARY_DIR)
+      set_target_properties(${target} PROPERTIES RUNTIME_OUTPUT_DIRECTORY ${ARG_BINARY_DIR})
+    endif()
+    if(ARG_LIBRARY_DIR)
+      set_target_properties(${target} PROPERTIES ARCHIVE_OUTPUT_DIRECTORY ${ARG_LIBRARY_DIR})
+    endif()
+    if(module_dir)
+      set_target_properties(${target} PROPERTIES LIBRARY_OUTPUT_DIRECTORY ${module_dir})
+    endif()
+  endif()
+endfunction()
+
+# If on Windows and building with MSVC, add the resource script containing the
+# VERSIONINFO data to the project.  This embeds version resource information
+# into the output .exe or .dll.
+# TODO: Enable for MinGW Windows builds too.
+#
+function(add_windows_version_resource_file OUT_VAR)
+  set(sources ${ARGN})
+  if (MSVC AND CMAKE_HOST_SYSTEM_NAME STREQUAL "Windows")
+    set(resource_file ${LLVM_SOURCE_DIR}/resources/windows_version_resource.rc)
+    if(EXISTS ${resource_file})
+      set(sources ${sources} ${resource_file})
+      source_group("Resource Files" ${resource_file})
+      set(windows_resource_file ${resource_file} PARENT_SCOPE)
+    endif()
+  endif(MSVC AND CMAKE_HOST_SYSTEM_NAME STREQUAL "Windows")
+
+  set(${OUT_VAR} ${sources} PARENT_SCOPE)
+endfunction(add_windows_version_resource_file)
+
+# set_windows_version_resource_properties(name resource_file...
+#   VERSION_MAJOR int
+#     Optional major version number (defaults to LLVM_VERSION_MAJOR)
+#   VERSION_MINOR int
+#     Optional minor version number (defaults to LLVM_VERSION_MINOR)
+#   VERSION_PATCHLEVEL int
+#     Optional patchlevel version number (defaults to LLVM_VERSION_PATCH)
+#   VERSION_STRING
+#     Optional version string (defaults to PACKAGE_VERSION)
+#   PRODUCT_NAME
+#     Optional product name string (defaults to "LLVM")
+#   )
+function(set_windows_version_resource_properties name resource_file)
+  cmake_parse_arguments(ARG
+    ""
+    "VERSION_MAJOR;VERSION_MINOR;VERSION_PATCHLEVEL;VERSION_STRING;PRODUCT_NAME"
+    ""
+    ${ARGN})
+
+  if (NOT DEFINED ARG_VERSION_MAJOR)
+    set(ARG_VERSION_MAJOR ${LLVM_VERSION_MAJOR})
+  endif()
+
+  if (NOT DEFINED ARG_VERSION_MINOR)
+    set(ARG_VERSION_MINOR ${LLVM_VERSION_MINOR})
+  endif()
+
+  if (NOT DEFINED ARG_VERSION_PATCHLEVEL)
+    set(ARG_VERSION_PATCHLEVEL ${LLVM_VERSION_PATCH})
+  endif()
+
+  if (NOT DEFINED ARG_VERSION_STRING)
+    set(ARG_VERSION_STRING ${PACKAGE_VERSION})
+  endif()
+
+  if (NOT DEFINED ARG_PRODUCT_NAME)
+    set(ARG_PRODUCT_NAME "LLVM")
+  endif()
+
+  set_property(SOURCE ${resource_file}
+               PROPERTY COMPILE_FLAGS /nologo)
+  set_property(SOURCE ${resource_file}
+               PROPERTY COMPILE_DEFINITIONS
+               "RC_VERSION_FIELD_1=${ARG_VERSION_MAJOR}"
+               "RC_VERSION_FIELD_2=${ARG_VERSION_MINOR}"
+               "RC_VERSION_FIELD_3=${ARG_VERSION_PATCHLEVEL}"
+               "RC_VERSION_FIELD_4=0"
+               "RC_FILE_VERSION=\"${ARG_VERSION_STRING}\""
+               "RC_INTERNAL_NAME=\"${name}\""
+               "RC_PRODUCT_NAME=\"${ARG_PRODUCT_NAME}\""
+               "RC_PRODUCT_VERSION=\"${ARG_VERSION_STRING}\"")
+endfunction(set_windows_version_resource_properties)
+
+# llvm_add_library(name sources...
+#   SHARED;STATIC
+#     STATIC by default w/o BUILD_SHARED_LIBS.
+#     SHARED by default w/  BUILD_SHARED_LIBS.
+#   OBJECT
+#     Also create an OBJECT library target. Default if STATIC && SHARED.
+#   MODULE
+#     Target ${name} might not be created on unsupported platforms.
+#     Check with "if(TARGET ${name})".
+#   DISABLE_LLVM_LINK_LLVM_DYLIB
+#     Do not link this library to libLLVM, even if
+#     LLVM_LINK_LLVM_DYLIB is enabled.
+#   OUTPUT_NAME name
+#     Corresponds to OUTPUT_NAME in target properties.
+#   DEPENDS targets...
+#     Same semantics as add_dependencies().
+#   LINK_COMPONENTS components...
+#     Same as the variable LLVM_LINK_COMPONENTS.
+#   LINK_LIBS lib_targets...
+#     Same semantics as target_link_libraries().
+#   ADDITIONAL_HEADERS
+#     May specify header files for IDE generators.
+#   SONAME
+#     Should set SONAME link flags and create symlinks
+#   PLUGIN_TOOL
+#     The tool (i.e. cmake target) that this plugin will link against
+#   )
+function(llvm_add_library name)
+  cmake_parse_arguments(ARG
+    "MODULE;SHARED;STATIC;OBJECT;DISABLE_LLVM_LINK_LLVM_DYLIB;SONAME"
+    "OUTPUT_NAME;PLUGIN_TOOL"
+    "ADDITIONAL_HEADERS;DEPENDS;LINK_COMPONENTS;LINK_LIBS;OBJLIBS"
+    ${ARGN})
+  list(APPEND LLVM_COMMON_DEPENDS ${ARG_DEPENDS})
+  if(ARG_ADDITIONAL_HEADERS)
+    # Pass through ADDITIONAL_HEADERS.
+    set(ARG_ADDITIONAL_HEADERS ADDITIONAL_HEADERS ${ARG_ADDITIONAL_HEADERS})
+  endif()
+  if(ARG_OBJLIBS)
+    set(ALL_FILES ${ARG_OBJLIBS})
+  else()
+    llvm_process_sources(ALL_FILES ${ARG_UNPARSED_ARGUMENTS} ${ARG_ADDITIONAL_HEADERS})
+  endif()
+
+  if(ARG_MODULE)
+    if(ARG_SHARED OR ARG_STATIC)
+      message(WARNING "MODULE with SHARED|STATIC doesn't make sense.")
+    endif()
+    # Plugins that link against a tool are allowed even when plugins in general are not
+    if(NOT LLVM_ENABLE_PLUGINS AND NOT (ARG_PLUGIN_TOOL AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS))
+      message(STATUS "${name} ignored -- Loadable modules not supported on this platform.")
+      return()
+    endif()
+  else()
+    if(ARG_PLUGIN_TOOL)
+      message(WARNING "PLUGIN_TOOL without MODULE doesn't make sense.")
+    endif()
+    if(BUILD_SHARED_LIBS AND NOT ARG_STATIC)
+      set(ARG_SHARED TRUE)
+    endif()
+    if(NOT ARG_SHARED)
+      set(ARG_STATIC TRUE)
+    endif()
+  endif()
+
+  # Generate objlib
+  if((ARG_SHARED AND ARG_STATIC) OR ARG_OBJECT)
+    # Generate an obj library for both targets.
+    set(obj_name "obj.${name}")
+    add_library(${obj_name} OBJECT EXCLUDE_FROM_ALL
+      ${ALL_FILES}
+      )
+    llvm_update_compile_flags(${obj_name})
+    set(ALL_FILES "$<TARGET_OBJECTS:${obj_name}>")
+
+    # Do add_dependencies(obj) later due to CMake issue 14747.
+    list(APPEND objlibs ${obj_name})
+
+    set_target_properties(${obj_name} PROPERTIES FOLDER "Object Libraries")
+  endif()
+
+  if(ARG_SHARED AND ARG_STATIC)
+    # static
+    set(name_static "${name}_static")
+    if(ARG_OUTPUT_NAME)
+      set(output_name OUTPUT_NAME "${ARG_OUTPUT_NAME}")
+    endif()
+    # DEPENDS has been appended to LLVM_COMMON_LIBS.
+    llvm_add_library(${name_static} STATIC
+      ${output_name}
+      OBJLIBS ${ALL_FILES} # objlib
+      LINK_LIBS ${ARG_LINK_LIBS}
+      LINK_COMPONENTS ${ARG_LINK_COMPONENTS}
+      )
+    # FIXME: Add name_static to anywhere in TARGET ${name}'s PROPERTY.
+    set(ARG_STATIC)
+  endif()
+
+  if(ARG_MODULE)
+    add_library(${name} MODULE ${ALL_FILES})
+    llvm_setup_rpath(${name})
+  elseif(ARG_SHARED)
+    add_windows_version_resource_file(ALL_FILES ${ALL_FILES})
+    add_library(${name} SHARED ${ALL_FILES})
+
+    llvm_setup_rpath(${name})
+
+  else()
+    add_library(${name} STATIC ${ALL_FILES})
+  endif()
+
+  setup_dependency_debugging(${name} ${LLVM_COMMON_DEPENDS})
+
+  if(DEFINED windows_resource_file)
+    set_windows_version_resource_properties(${name} ${windows_resource_file})
+    set(windows_resource_file ${windows_resource_file} PARENT_SCOPE)
+  endif()
+
+  set_output_directory(${name} BINARY_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR} LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
+  # $<TARGET_OBJECTS> doesn't require compile flags.
+  if(NOT obj_name)
+    llvm_update_compile_flags(${name})
+  endif()
+  add_link_opts( ${name} )
+  if(ARG_OUTPUT_NAME)
+    set_target_properties(${name}
+      PROPERTIES
+      OUTPUT_NAME ${ARG_OUTPUT_NAME}
+      )
+  endif()
+
+  if(ARG_MODULE)
+    set_target_properties(${name} PROPERTIES
+      PREFIX ""
+      SUFFIX ${LLVM_PLUGIN_EXT}
+      )
+  endif()
+
+  if(ARG_SHARED)
+    if(WIN32)
+      set_target_properties(${name} PROPERTIES
+        PREFIX ""
+        )
+    endif()
+
+    # Set SOVERSION on shared libraries that lack explicit SONAME
+    # specifier, on *nix systems that are not Darwin.
+    if(UNIX AND NOT APPLE AND NOT ARG_SONAME)
+      set_target_properties(${name}
+        PROPERTIES
+        # Since 4.0.0, the ABI version is indicated by the major version
+        SOVERSION ${LLVM_VERSION_MAJOR}
+        VERSION ${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX})
+    endif()
+  endif()
+
+  if(ARG_MODULE OR ARG_SHARED)
+    # Do not add -Dname_EXPORTS to the command-line when building files in this
+    # target. Doing so is actively harmful for the modules build because it
+    # creates extra module variants, and not useful because we don't use these
+    # macros.
+    set_target_properties( ${name} PROPERTIES DEFINE_SYMBOL "" )
+
+    if (LLVM_EXPORTED_SYMBOL_FILE)
+      add_llvm_symbol_exports( ${name} ${LLVM_EXPORTED_SYMBOL_FILE} )
+    endif()
+  endif()
+
+  if(ARG_SHARED AND UNIX)
+    if(NOT APPLE AND ARG_SONAME)
+      get_target_property(output_name ${name} OUTPUT_NAME)
+      if(${output_name} STREQUAL "output_name-NOTFOUND")
+        set(output_name ${name})
+      endif()
+      set(library_name ${output_name}-${LLVM_VERSION_MAJOR}${LLVM_VERSION_SUFFIX})
+      set(api_name ${output_name}-${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.${LLVM_VERSION_PATCH}${LLVM_VERSION_SUFFIX})
+      set_target_properties(${name} PROPERTIES OUTPUT_NAME ${library_name})
+      llvm_install_library_symlink(${api_name} ${library_name} SHARED
+        COMPONENT ${name}
+        ALWAYS_GENERATE)
+      llvm_install_library_symlink(${output_name} ${library_name} SHARED
+        COMPONENT ${name}
+        ALWAYS_GENERATE)
+    endif()
+  endif()
+
+  if(ARG_MODULE AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS AND ARG_PLUGIN_TOOL AND (WIN32 OR CYGWIN))
+    # On DLL platforms symbols are imported from the tool by linking against it.
+    set(llvm_libs ${ARG_PLUGIN_TOOL})
+  elseif (DEFINED LLVM_LINK_COMPONENTS OR DEFINED ARG_LINK_COMPONENTS)
+    if (LLVM_LINK_LLVM_DYLIB AND NOT ARG_DISABLE_LLVM_LINK_LLVM_DYLIB)
+      set(llvm_libs LLVM)
+    else()
+      llvm_map_components_to_libnames(llvm_libs
+       ${ARG_LINK_COMPONENTS}
+       ${LLVM_LINK_COMPONENTS}
+       )
+    endif()
+  else()
+    # Components have not been defined explicitly in CMake, so add the
+    # dependency information for this library as defined by LLVMBuild.
+    #
+    # It would be nice to verify that we have the dependencies for this library
+    # name, but using get_property(... SET) doesn't suffice to determine if a
+    # property has been set to an empty value.
+    get_property(lib_deps GLOBAL PROPERTY LLVMBUILD_LIB_DEPS_${name})
+  endif()
+
+  if(ARG_STATIC)
+    set(libtype INTERFACE)
+  else()
+    # We can use PRIVATE since SO knows its dependent libs.
+    set(libtype PRIVATE)
+  endif()
+
+  target_link_libraries(${name} ${libtype}
+      ${ARG_LINK_LIBS}
+      ${lib_deps}
+      ${llvm_libs}
+      )
+
+  if(LLVM_COMMON_DEPENDS)
+    add_dependencies(${name} ${LLVM_COMMON_DEPENDS})
+    # Add dependencies also to objlibs.
+    # CMake issue 14747 --  add_dependencies() might be ignored to objlib's user.
+    foreach(objlib ${objlibs})
+      add_dependencies(${objlib} ${LLVM_COMMON_DEPENDS})
+    endforeach()
+  endif()
+
+  if(ARG_SHARED OR ARG_MODULE)
+    llvm_externalize_debuginfo(${name})
+  endif()
+endfunction()
+
+function(add_llvm_install_targets target)
+  cmake_parse_arguments(ARG "" "COMPONENT;PREFIX" "DEPENDS" ${ARGN})
+  if(ARG_COMPONENT)
+    set(component_option -DCMAKE_INSTALL_COMPONENT="${ARG_COMPONENT}")
+  endif()
+  if(ARG_PREFIX)
+    set(prefix_option -DCMAKE_INSTALL_PREFIX="${ARG_PREFIX}")
+  endif()
+
+  add_custom_target(${target}
+                    DEPENDS ${ARG_DEPENDS}
+                    COMMAND "${CMAKE_COMMAND}"
+                            ${component_option}
+                            ${prefix_option}
+                            -P "${CMAKE_BINARY_DIR}/cmake_install.cmake"
+                    USES_TERMINAL)
+  add_custom_target(${target}-stripped
+                    DEPENDS ${ARG_DEPENDS}
+                    COMMAND "${CMAKE_COMMAND}"
+                            ${component_option}
+                            ${prefix_option}
+                            -DCMAKE_INSTALL_DO_STRIP=1
+                            -P "${CMAKE_BINARY_DIR}/cmake_install.cmake"
+                    USES_TERMINAL)
+endfunction()
+
+macro(add_llvm_library name)
+  cmake_parse_arguments(ARG
+    "SHARED;BUILDTREE_ONLY"
+    ""
+    ""
+    ${ARGN})
+  if( BUILD_SHARED_LIBS OR ARG_SHARED )
+    llvm_add_library(${name} SHARED ${ARG_UNPARSED_ARGUMENTS})
+  else()
+    llvm_add_library(${name} ${ARG_UNPARSED_ARGUMENTS})
+  endif()
+
+  # Libraries that are meant to only be exposed via the build tree only are
+  # never installed and are only exported as a target in the special build tree
+  # config file.
+  if (NOT ARG_BUILDTREE_ONLY)
+    set_property( GLOBAL APPEND PROPERTY LLVM_LIBS ${name} )
+  endif()
+
+  if( EXCLUDE_FROM_ALL )
+    set_target_properties( ${name} PROPERTIES EXCLUDE_FROM_ALL ON)
+  elseif(ARG_BUILDTREE_ONLY)
+    set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS_BUILDTREE_ONLY ${name})
+  else()
+    if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY OR ${name} STREQUAL "LTO" OR
+        (LLVM_LINK_LLVM_DYLIB AND ${name} STREQUAL "LLVM"))
+      set(install_dir lib${LLVM_LIBDIR_SUFFIX})
+      if(ARG_SHARED OR BUILD_SHARED_LIBS)
+        if(WIN32 OR CYGWIN OR MINGW)
+          set(install_type RUNTIME)
+          set(install_dir bin)
+        else()
+          set(install_type LIBRARY)
+        endif()
+      else()
+        set(install_type ARCHIVE)
+      endif()
+
+      if(${name} IN_LIST LLVM_DISTRIBUTION_COMPONENTS OR
+          NOT LLVM_DISTRIBUTION_COMPONENTS)
+        set(export_to_llvmexports EXPORT LLVMExports)
+        set_property(GLOBAL PROPERTY LLVM_HAS_EXPORTS True)
+      endif()
+
+      install(TARGETS ${name}
+              ${export_to_llvmexports}
+              ${install_type} DESTINATION ${install_dir}
+              COMPONENT ${name})
+
+      if (NOT CMAKE_CONFIGURATION_TYPES)
+        add_llvm_install_targets(install-${name}
+                                 DEPENDS ${name}
+                                 COMPONENT ${name})
+      endif()
+    endif()
+    set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS ${name})
+  endif()
+  set_target_properties(${name} PROPERTIES FOLDER "Libraries")
+endmacro(add_llvm_library name)
+
+macro(add_llvm_loadable_module name)
+  llvm_add_library(${name} MODULE ${ARGN})
+  if(NOT TARGET ${name})
+    # Add empty "phony" target
+    add_custom_target(${name})
+  else()
+    if( EXCLUDE_FROM_ALL )
+      set_target_properties( ${name} PROPERTIES EXCLUDE_FROM_ALL ON)
+    else()
+      if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
+        if(WIN32 OR CYGWIN)
+          # DLL platform
+          set(dlldir "bin")
+        else()
+          set(dlldir "lib${LLVM_LIBDIR_SUFFIX}")
+        endif()
+
+        if(${name} IN_LIST LLVM_DISTRIBUTION_COMPONENTS OR
+            NOT LLVM_DISTRIBUTION_COMPONENTS)
+          set(export_to_llvmexports EXPORT LLVMExports)
+          set_property(GLOBAL PROPERTY LLVM_HAS_EXPORTS True)
+        endif()
+
+        install(TARGETS ${name}
+                ${export_to_llvmexports}
+                LIBRARY DESTINATION ${dlldir}
+                ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX})
+      endif()
+      set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS ${name})
+    endif()
+  endif()
+
+  set_target_properties(${name} PROPERTIES FOLDER "Loadable modules")
+endmacro(add_llvm_loadable_module name)
+
+
+macro(add_llvm_executable name)
+  cmake_parse_arguments(ARG "DISABLE_LLVM_LINK_LLVM_DYLIB;IGNORE_EXTERNALIZE_DEBUGINFO;NO_INSTALL_RPATH" "" "DEPENDS" ${ARGN})
+  llvm_process_sources( ALL_FILES ${ARG_UNPARSED_ARGUMENTS} )
+
+  list(APPEND LLVM_COMMON_DEPENDS ${ARG_DEPENDS})
+
+  # Generate objlib
+  if(LLVM_ENABLE_OBJLIB)
+    # Generate an obj library for both targets.
+    set(obj_name "obj.${name}")
+    add_library(${obj_name} OBJECT EXCLUDE_FROM_ALL
+      ${ALL_FILES}
+      )
+    llvm_update_compile_flags(${obj_name})
+    set(ALL_FILES "$<TARGET_OBJECTS:${obj_name}>")
+
+    set_target_properties(${obj_name} PROPERTIES FOLDER "Object Libraries")
+  endif()
+
+  add_windows_version_resource_file(ALL_FILES ${ALL_FILES})
+
+  if(XCODE)
+    # Note: the dummy.cpp source file provides no definitions. However,
+    # it forces Xcode to properly link the static library.
+    list(APPEND ALL_FILES "${LLVM_MAIN_SRC_DIR}/cmake/dummy.cpp")
+  endif()
+
+  if( EXCLUDE_FROM_ALL )
+    add_executable(${name} EXCLUDE_FROM_ALL ${ALL_FILES})
+  else()
+    add_executable(${name} ${ALL_FILES})
+  endif()
+
+  setup_dependency_debugging(${name} ${LLVM_COMMON_DEPENDS})
+
+  if(NOT ARG_NO_INSTALL_RPATH)
+    llvm_setup_rpath(${name})
+  endif()
+
+  if(DEFINED windows_resource_file)
+    set_windows_version_resource_properties(${name} ${windows_resource_file})
+  endif()
+
+  # $<TARGET_OBJECTS> doesn't require compile flags.
+  if(NOT LLVM_ENABLE_OBJLIB)
+    llvm_update_compile_flags(${name})
+  endif()
+  add_link_opts( ${name} )
+
+  # Do not add -Dname_EXPORTS to the command-line when building files in this
+  # target. Doing so is actively harmful for the modules build because it
+  # creates extra module variants, and not useful because we don't use these
+  # macros.
+  set_target_properties( ${name} PROPERTIES DEFINE_SYMBOL "" )
+
+  if (LLVM_EXPORTED_SYMBOL_FILE)
+    add_llvm_symbol_exports( ${name} ${LLVM_EXPORTED_SYMBOL_FILE} )
+  endif(LLVM_EXPORTED_SYMBOL_FILE)
+
+  if (LLVM_LINK_LLVM_DYLIB AND NOT ARG_DISABLE_LLVM_LINK_LLVM_DYLIB)
+    set(USE_SHARED USE_SHARED)
+  endif()
+
+  set(EXCLUDE_FROM_ALL OFF)
+  set_output_directory(${name} BINARY_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR} LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
+  llvm_config( ${name} ${USE_SHARED} ${LLVM_LINK_COMPONENTS} )
+  if( LLVM_COMMON_DEPENDS )
+    add_dependencies( ${name} ${LLVM_COMMON_DEPENDS} )
+  endif( LLVM_COMMON_DEPENDS )
+
+  if(NOT ARG_IGNORE_EXTERNALIZE_DEBUGINFO)
+    llvm_externalize_debuginfo(${name})
+  endif()
+  if (LLVM_PTHREAD_LIB)
+    # libpthreads overrides some standard library symbols, so main
+    # executable must be linked with it in order to provide consistent
+    # API for all shared libaries loaded by this executable.
+    target_link_libraries(${name} PRIVATE ${LLVM_PTHREAD_LIB})
+  endif()
+endmacro(add_llvm_executable name)
+
+function(export_executable_symbols target)
+  if (LLVM_EXPORTED_SYMBOL_FILE)
+    # The symbol file should contain the symbols we want the executable to
+    # export
+    set_target_properties(${target} PROPERTIES ENABLE_EXPORTS 1)
+  elseif (LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
+    # Extract the symbols to export from the static libraries that the
+    # executable links against.
+    set_target_properties(${target} PROPERTIES ENABLE_EXPORTS 1)
+    set(exported_symbol_file ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/${target}.symbols)
+    # We need to consider not just the direct link dependencies, but also the
+    # transitive link dependencies. Do this by starting with the set of direct
+    # dependencies, then the dependencies of those dependencies, and so on.
+    get_target_property(new_libs ${target} LINK_LIBRARIES)
+    set(link_libs ${new_libs})
+    while(NOT "${new_libs}" STREQUAL "")
+      foreach(lib ${new_libs})
+        if(TARGET ${lib})
+          get_target_property(lib_type ${lib} TYPE)
+          if("${lib_type}" STREQUAL "STATIC_LIBRARY")
+            list(APPEND static_libs ${lib})
+          else()
+            list(APPEND other_libs ${lib})
+          endif()
+          get_target_property(transitive_libs ${lib} INTERFACE_LINK_LIBRARIES)
+          foreach(transitive_lib ${transitive_libs})
+            list(FIND link_libs ${transitive_lib} idx)
+            if(TARGET ${transitive_lib} AND idx EQUAL -1)
+              list(APPEND newer_libs ${transitive_lib})
+              list(APPEND link_libs ${transitive_lib})
+            endif()
+          endforeach(transitive_lib)
+        endif()
+      endforeach(lib)
+      set(new_libs ${newer_libs})
+      set(newer_libs "")
+    endwhile()
+    if (MSVC)
+      set(mangling microsoft)
+    else()
+      set(mangling itanium)
+    endif()
+    add_custom_command(OUTPUT ${exported_symbol_file}
+                       COMMAND ${PYTHON_EXECUTABLE} ${LLVM_MAIN_SRC_DIR}/utils/extract_symbols.py --mangling=${mangling} ${static_libs} -o ${exported_symbol_file}
+                       WORKING_DIRECTORY ${LLVM_LIBRARY_OUTPUT_INTDIR}
+                       DEPENDS ${LLVM_MAIN_SRC_DIR}/utils/extract_symbols.py ${static_libs}
+                       VERBATIM
+                       COMMENT "Generating export list for ${target}")
+    add_llvm_symbol_exports( ${target} ${exported_symbol_file} )
+    # If something links against this executable then we want a
+    # transitive link against only the libraries whose symbols
+    # we aren't exporting.
+    set_target_properties(${target} PROPERTIES INTERFACE_LINK_LIBRARIES "${other_libs}")
+    # The default import library suffix that cmake uses for cygwin/mingw is
+    # ".dll.a", but for clang.exe that causes a collision with libclang.dll,
+    # where the import libraries of both get named libclang.dll.a. Use a suffix
+    # of ".exe.a" to avoid this.
+    if(CYGWIN OR MINGW)
+      set_target_properties(${target} PROPERTIES IMPORT_SUFFIX ".exe.a")
+    endif()
+  elseif(NOT (WIN32 OR CYGWIN))
+    # On Windows auto-exporting everything doesn't work because of the limit on
+    # the size of the exported symbol table, but on other platforms we can do
+    # it without any trouble.
+    set_target_properties(${target} PROPERTIES ENABLE_EXPORTS 1)
+    if (APPLE)
+      set_property(TARGET ${target} APPEND_STRING PROPERTY
+        LINK_FLAGS " -rdynamic")
+    endif()
+  endif()
+endfunction()
+
+if(NOT LLVM_TOOLCHAIN_TOOLS)
+  set (LLVM_TOOLCHAIN_TOOLS
+    llvm-ar
+    llvm-ranlib
+    llvm-lib
+    llvm-objdump
+    )
+endif()
+
+macro(add_llvm_tool name)
+  if( NOT LLVM_BUILD_TOOLS )
+    set(EXCLUDE_FROM_ALL ON)
+  endif()
+  add_llvm_executable(${name} ${ARGN})
+
+  if ( ${name} IN_LIST LLVM_TOOLCHAIN_TOOLS OR NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
+    if( LLVM_BUILD_TOOLS )
+      if(${name} IN_LIST LLVM_DISTRIBUTION_COMPONENTS OR
+          NOT LLVM_DISTRIBUTION_COMPONENTS)
+        set(export_to_llvmexports EXPORT LLVMExports)
+        set_property(GLOBAL PROPERTY LLVM_HAS_EXPORTS True)
+      endif()
+
+      install(TARGETS ${name}
+              ${export_to_llvmexports}
+              RUNTIME DESTINATION ${LLVM_TOOLS_INSTALL_DIR}
+              COMPONENT ${name})
+
+      if (NOT CMAKE_CONFIGURATION_TYPES)
+        add_llvm_install_targets(install-${name}
+                                 DEPENDS ${name}
+                                 COMPONENT ${name})
+      endif()
+    endif()
+  endif()
+  if( LLVM_BUILD_TOOLS )
+    set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS ${name})
+  endif()
+  set_target_properties(${name} PROPERTIES FOLDER "Tools")
+endmacro(add_llvm_tool name)
+
+
+macro(add_llvm_example name)
+  if( NOT LLVM_BUILD_EXAMPLES )
+    set(EXCLUDE_FROM_ALL ON)
+  endif()
+  add_llvm_executable(${name} ${ARGN})
+  if( LLVM_BUILD_EXAMPLES )
+    install(TARGETS ${name} RUNTIME DESTINATION examples)
+  endif()
+  set_target_properties(${name} PROPERTIES FOLDER "Examples")
+endmacro(add_llvm_example name)
+
+# This is a macro that is used to create targets for executables that are needed
+# for development, but that are not intended to be installed by default.
+macro(add_llvm_utility name)
+  if ( NOT LLVM_BUILD_UTILS )
+    set(EXCLUDE_FROM_ALL ON)
+  endif()
+
+  add_llvm_executable(${name} DISABLE_LLVM_LINK_LLVM_DYLIB ${ARGN})
+  set_target_properties(${name} PROPERTIES FOLDER "Utils")
+  if( LLVM_INSTALL_UTILS AND LLVM_BUILD_UTILS )
+    install (TARGETS ${name}
+      RUNTIME DESTINATION ${LLVM_UTILS_INSTALL_DIR}
+      COMPONENT ${name})
+    if (NOT CMAKE_CONFIGURATION_TYPES)
+      add_llvm_install_targets(install-${name}
+                               DEPENDS ${name}
+                               COMPONENT ${name})
+    endif()
+  endif()
+endmacro(add_llvm_utility name)
+
+macro(add_llvm_fuzzer name)
+  cmake_parse_arguments(ARG "" "DUMMY_MAIN" "" ${ARGN})
+  if( LLVM_LIB_FUZZING_ENGINE )
+    set(LLVM_OPTIONAL_SOURCES ${ARG_DUMMY_MAIN})
+    add_llvm_executable(${name} ${ARG_UNPARSED_ARGUMENTS})
+    target_link_libraries(${name} PRIVATE ${LLVM_LIB_FUZZING_ENGINE})
+    set_target_properties(${name} PROPERTIES FOLDER "Fuzzers")
+  elseif( LLVM_USE_SANITIZE_COVERAGE )
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=fuzzer")
+    set(LLVM_OPTIONAL_SOURCES ${ARG_DUMMY_MAIN})
+    add_llvm_executable(${name} ${ARG_UNPARSED_ARGUMENTS})
+    set_target_properties(${name} PROPERTIES FOLDER "Fuzzers")
+  elseif( ARG_DUMMY_MAIN )
+    add_llvm_executable(${name} ${ARG_DUMMY_MAIN} ${ARG_UNPARSED_ARGUMENTS})
+    set_target_properties(${name} PROPERTIES FOLDER "Fuzzers")
+  endif()
+endmacro()
+
+macro(add_llvm_target target_name)
+  include_directories(BEFORE
+    ${CMAKE_CURRENT_BINARY_DIR}
+    ${CMAKE_CURRENT_SOURCE_DIR})
+  add_llvm_library(LLVM${target_name} ${ARGN})
+  set( CURRENT_LLVM_TARGET LLVM${target_name} )
+endmacro(add_llvm_target)
+
+function(canonicalize_tool_name name output)
+  string(REPLACE "${CMAKE_CURRENT_SOURCE_DIR}/" "" nameStrip ${name})
+  string(REPLACE "-" "_" nameUNDERSCORE ${nameStrip})
+  string(TOUPPER ${nameUNDERSCORE} nameUPPER)
+  set(${output} "${nameUPPER}" PARENT_SCOPE)
+endfunction(canonicalize_tool_name)
+
+# Custom add_subdirectory wrapper
+# Takes in a project name (i.e. LLVM), the subdirectory name, and an optional
+# path if it differs from the name.
+macro(add_llvm_subdirectory project type name)
+  set(add_llvm_external_dir "${ARGN}")
+  if("${add_llvm_external_dir}" STREQUAL "")
+    set(add_llvm_external_dir ${name})
+  endif()
+  canonicalize_tool_name(${name} nameUPPER)
+  if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${add_llvm_external_dir}/CMakeLists.txt)
+    # Treat it as in-tree subproject.
+    option(${project}_${type}_${nameUPPER}_BUILD
+           "Whether to build ${name} as part of ${project}" On)
+    mark_as_advanced(${project}_${type}_${name}_BUILD)
+    if(${project}_${type}_${nameUPPER}_BUILD)
+      add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${add_llvm_external_dir} ${add_llvm_external_dir})
+      # Don't process it in add_llvm_implicit_projects().
+      set(${project}_${type}_${nameUPPER}_BUILD OFF)
+    endif()
+  else()
+    set(LLVM_EXTERNAL_${nameUPPER}_SOURCE_DIR
+      "${LLVM_EXTERNAL_${nameUPPER}_SOURCE_DIR}"
+      CACHE PATH "Path to ${name} source directory")
+    set(${project}_${type}_${nameUPPER}_BUILD_DEFAULT ON)
+    if(NOT LLVM_EXTERNAL_${nameUPPER}_SOURCE_DIR OR NOT EXISTS ${LLVM_EXTERNAL_${nameUPPER}_SOURCE_DIR})
+      set(${project}_${type}_${nameUPPER}_BUILD_DEFAULT OFF)
+    endif()
+    if("${LLVM_EXTERNAL_${nameUPPER}_BUILD}" STREQUAL "OFF")
+      set(${project}_${type}_${nameUPPER}_BUILD_DEFAULT OFF)
+    endif()
+    option(${project}_${type}_${nameUPPER}_BUILD
+      "Whether to build ${name} as part of LLVM"
+      ${${project}_${type}_${nameUPPER}_BUILD_DEFAULT})
+    if (${project}_${type}_${nameUPPER}_BUILD)
+      if(EXISTS ${LLVM_EXTERNAL_${nameUPPER}_SOURCE_DIR})
+        add_subdirectory(${LLVM_EXTERNAL_${nameUPPER}_SOURCE_DIR} ${add_llvm_external_dir})
+      elseif(NOT "${LLVM_EXTERNAL_${nameUPPER}_SOURCE_DIR}" STREQUAL "")
+        message(WARNING "Nonexistent directory for ${name}: ${LLVM_EXTERNAL_${nameUPPER}_SOURCE_DIR}")
+      endif()
+      # FIXME: It'd be redundant.
+      set(${project}_${type}_${nameUPPER}_BUILD Off)
+    endif()
+  endif()
+endmacro()
+
+# Add external project that may want to be built as part of llvm such as Clang,
+# lld, and Polly. This adds two options. One for the source directory of the
+# project, which defaults to ${CMAKE_CURRENT_SOURCE_DIR}/${name}. Another to
+# enable or disable building it with everything else.
+# Additional parameter can be specified as the name of directory.
+macro(add_llvm_external_project name)
+  add_llvm_subdirectory(LLVM TOOL ${name} ${ARGN})
+endmacro()
+
+macro(add_llvm_tool_subdirectory name)
+  add_llvm_external_project(${name})
+endmacro(add_llvm_tool_subdirectory)
+
+function(get_project_name_from_src_var var output)
+  string(REGEX MATCH "LLVM_EXTERNAL_(.*)_SOURCE_DIR"
+         MACHED_TOOL "${var}")
+  if(MACHED_TOOL)
+    set(${output} ${CMAKE_MATCH_1} PARENT_SCOPE)
+  else()
+    set(${output} PARENT_SCOPE)
+  endif()
+endfunction()
+
+function(create_subdirectory_options project type)
+  file(GLOB sub-dirs "${CMAKE_CURRENT_SOURCE_DIR}/*")
+  foreach(dir ${sub-dirs})
+    if(IS_DIRECTORY "${dir}" AND EXISTS "${dir}/CMakeLists.txt")
+      canonicalize_tool_name(${dir} name)
+      option(${project}_${type}_${name}_BUILD
+           "Whether to build ${name} as part of ${project}" On)
+      mark_as_advanced(${project}_${type}_${name}_BUILD)
+    endif()
+  endforeach()
+endfunction(create_subdirectory_options)
+
+function(create_llvm_tool_options)
+  create_subdirectory_options(LLVM TOOL)
+endfunction(create_llvm_tool_options)
+
+function(llvm_add_implicit_projects project)
+  set(list_of_implicit_subdirs "")
+  file(GLOB sub-dirs "${CMAKE_CURRENT_SOURCE_DIR}/*")
+  foreach(dir ${sub-dirs})
+    if(IS_DIRECTORY "${dir}" AND EXISTS "${dir}/CMakeLists.txt")
+      canonicalize_tool_name(${dir} name)
+      if (${project}_TOOL_${name}_BUILD)
+        get_filename_component(fn "${dir}" NAME)
+        list(APPEND list_of_implicit_subdirs "${fn}")
+      endif()
+    endif()
+  endforeach()
+
+  foreach(external_proj ${list_of_implicit_subdirs})
+    add_llvm_subdirectory(${project} TOOL "${external_proj}" ${ARGN})
+  endforeach()
+endfunction(llvm_add_implicit_projects)
+
+function(add_llvm_implicit_projects)
+  llvm_add_implicit_projects(LLVM)
+endfunction(add_llvm_implicit_projects)
+
+# Generic support for adding a unittest.
+function(add_unittest test_suite test_name)
+  if( NOT LLVM_BUILD_TESTS )
+    set(EXCLUDE_FROM_ALL ON)
+  endif()
+
+  # Our current version of gtest does not properly recognize C++11 support
+  # with MSVC, so it falls back to tr1 / experimental classes.  Since LLVM
+  # itself requires C++11, we can safely force it on unconditionally so that
+  # we don't have to fight with the buggy gtest check.  
+  add_definitions(-DGTEST_LANG_CXX11=1)
+  add_definitions(-DGTEST_HAS_TR1_TUPLE=0)
+
+  include_directories(${LLVM_MAIN_SRC_DIR}/utils/unittest/googletest/include)
+  include_directories(${LLVM_MAIN_SRC_DIR}/utils/unittest/googlemock/include)
+  if (NOT LLVM_ENABLE_THREADS)
+    list(APPEND LLVM_COMPILE_DEFINITIONS GTEST_HAS_PTHREAD=0)
+  endif ()
+
+  if (SUPPORTS_VARIADIC_MACROS_FLAG)
+    list(APPEND LLVM_COMPILE_FLAGS "-Wno-variadic-macros")
+  endif ()
+  # Some parts of gtest rely on this GNU extension, don't warn on it.
+  if(SUPPORTS_GNU_ZERO_VARIADIC_MACRO_ARGUMENTS_FLAG)
+    list(APPEND LLVM_COMPILE_FLAGS "-Wno-gnu-zero-variadic-macro-arguments")
+  endif()
+
+  set(LLVM_REQUIRES_RTTI OFF)
+
+  list(APPEND LLVM_LINK_COMPONENTS Support) # gtest needs it for raw_ostream
+  add_llvm_executable(${test_name} IGNORE_EXTERNALIZE_DEBUGINFO NO_INSTALL_RPATH ${ARGN})
+  set(outdir ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR})
+  set_output_directory(${test_name} BINARY_DIR ${outdir} LIBRARY_DIR ${outdir})
+  # libpthreads overrides some standard library symbols, so main
+  # executable must be linked with it in order to provide consistent
+  # API for all shared libaries loaded by this executable.
+  target_link_libraries(${test_name} PRIVATE gtest_main gtest ${LLVM_PTHREAD_LIB})
+
+  add_dependencies(${test_suite} ${test_name})
+  get_target_property(test_suite_folder ${test_suite} FOLDER)
+  if (NOT ${test_suite_folder} STREQUAL "NOTFOUND")
+    set_property(TARGET ${test_name} PROPERTY FOLDER "${test_suite_folder}")
+  endif ()
+endfunction()
+
+function(llvm_add_go_executable binary pkgpath)
+  cmake_parse_arguments(ARG "ALL" "" "DEPENDS;GOFLAGS" ${ARGN})
+
+  if(LLVM_BINDINGS MATCHES "go")
+    # FIXME: This should depend only on the libraries Go needs.
+    get_property(llvmlibs GLOBAL PROPERTY LLVM_LIBS)
+    set(binpath ${CMAKE_BINARY_DIR}/bin/${binary}${CMAKE_EXECUTABLE_SUFFIX})
+    set(cc "${CMAKE_C_COMPILER} ${CMAKE_C_COMPILER_ARG1}")
+    set(cxx "${CMAKE_CXX_COMPILER} ${CMAKE_CXX_COMPILER_ARG1}")
+    set(cppflags "")
+    get_property(include_dirs DIRECTORY PROPERTY INCLUDE_DIRECTORIES)
+    foreach(d ${include_dirs})
+      set(cppflags "${cppflags} -I${d}")
+    endforeach(d)
+    set(ldflags "${CMAKE_EXE_LINKER_FLAGS}")
+    add_custom_command(OUTPUT ${binpath}
+      COMMAND ${CMAKE_BINARY_DIR}/bin/llvm-go "go=${GO_EXECUTABLE}" "cc=${cc}" "cxx=${cxx}" "cppflags=${cppflags}" "ldflags=${ldflags}" "packages=${LLVM_GO_PACKAGES}"
+              ${ARG_GOFLAGS} build -o ${binpath} ${pkgpath}
+      DEPENDS llvm-config ${CMAKE_BINARY_DIR}/bin/llvm-go${CMAKE_EXECUTABLE_SUFFIX}
+              ${llvmlibs} ${ARG_DEPENDS}
+      COMMENT "Building Go executable ${binary}"
+      VERBATIM)
+    if (ARG_ALL)
+      add_custom_target(${binary} ALL DEPENDS ${binpath})
+    else()
+      add_custom_target(${binary} DEPENDS ${binpath})
+    endif()
+  endif()
+endfunction()
+
+# This function canonicalize the CMake variables passed by names
+# from CMake boolean to 0/1 suitable for passing into Python or C++,
+# in place.
+function(llvm_canonicalize_cmake_booleans)
+  foreach(var ${ARGN})
+    if(${var})
+      set(${var} 1 PARENT_SCOPE)
+    else()
+      set(${var} 0 PARENT_SCOPE)
+    endif()
+  endforeach()
+endfunction(llvm_canonicalize_cmake_booleans)
+
+macro(set_llvm_build_mode)
+  # Configuration-time: See Unit/lit.site.cfg.in
+  if (CMAKE_CFG_INTDIR STREQUAL ".")
+    set(LLVM_BUILD_MODE ".")
+  else ()
+    set(LLVM_BUILD_MODE "%(build_mode)s")
+  endif ()
+endmacro()
+
+# This function provides an automatic way to 'configure'-like generate a file
+# based on a set of common and custom variables, specifically targeting the
+# variables needed for the 'lit.site.cfg' files. This function bundles the
+# common variables that any Lit instance is likely to need, and custom
+# variables can be passed in.
+function(configure_lit_site_cfg site_in site_out)
+  cmake_parse_arguments(ARG "" "" "MAIN_CONFIG;OUTPUT_MAPPING" ${ARGN})
+
+  if ("${ARG_MAIN_CONFIG}" STREQUAL "")
+    get_filename_component(INPUT_DIR ${site_in} DIRECTORY)
+    set(ARG_MAIN_CONFIG "${INPUT_DIR}/lit.cfg")
+  endif()
+  if ("${ARG_OUTPUT_MAPPING}" STREQUAL "")
+    set(ARG_OUTPUT_MAPPING "${site_out}")
+  endif()
+
+  foreach(c ${LLVM_TARGETS_TO_BUILD})
+    set(TARGETS_BUILT "${TARGETS_BUILT} ${c}")
+  endforeach(c)
+  set(TARGETS_TO_BUILD ${TARGETS_BUILT})
+
+  set(SHLIBEXT "${LTDL_SHLIB_EXT}")
+
+  set_llvm_build_mode()
+
+  # They below might not be the build tree but provided binary tree.
+  set(LLVM_SOURCE_DIR ${LLVM_MAIN_SRC_DIR})
+  set(LLVM_BINARY_DIR ${LLVM_BINARY_DIR})
+  string(REPLACE "${CMAKE_CFG_INTDIR}" "${LLVM_BUILD_MODE}" LLVM_TOOLS_DIR "${LLVM_TOOLS_BINARY_DIR}")
+  string(REPLACE ${CMAKE_CFG_INTDIR} ${LLVM_BUILD_MODE} LLVM_LIBS_DIR  "${LLVM_LIBRARY_DIR}")
+
+  # SHLIBDIR points the build tree.
+  string(REPLACE "${CMAKE_CFG_INTDIR}" "${LLVM_BUILD_MODE}" SHLIBDIR "${LLVM_SHLIB_OUTPUT_INTDIR}")
+
+  set(PYTHON_EXECUTABLE ${PYTHON_EXECUTABLE})
+  # FIXME: "ENABLE_SHARED" doesn't make sense, since it is used just for
+  # plugins. We may rename it.
+  if(LLVM_ENABLE_PLUGINS)
+    set(ENABLE_SHARED "1")
+  else()
+    set(ENABLE_SHARED "0")
+  endif()
+
+  if(LLVM_ENABLE_ASSERTIONS AND NOT MSVC_IDE)
+    set(ENABLE_ASSERTIONS "1")
+  else()
+    set(ENABLE_ASSERTIONS "0")
+  endif()
+
+  set(HOST_OS ${CMAKE_SYSTEM_NAME})
+  set(HOST_ARCH ${CMAKE_SYSTEM_PROCESSOR})
+
+  set(HOST_CC "${CMAKE_C_COMPILER} ${CMAKE_C_COMPILER_ARG1}")
+  set(HOST_CXX "${CMAKE_CXX_COMPILER} ${CMAKE_CXX_COMPILER_ARG1}")
+  set(HOST_LDFLAGS "${CMAKE_EXE_LINKER_FLAGS}")
+
+  set(LIT_SITE_CFG_IN_HEADER  "## Autogenerated from ${site_in}\n## Do not edit!")
+
+  # Override config_target_triple (and the env)
+  if(LLVM_TARGET_TRIPLE_ENV)
+    # This is expanded into the heading.
+    string(CONCAT LIT_SITE_CFG_IN_HEADER "${LIT_SITE_CFG_IN_HEADER}\n\n"
+      "import os\n"
+      "target_env = \"${LLVM_TARGET_TRIPLE_ENV}\"\n"
+      "config.target_triple = config.environment[target_env] = os.environ.get(target_env, \"${TARGET_TRIPLE}\")\n"
+      )
+
+    # This is expanded to; config.target_triple = ""+config.target_triple+""
+    set(TARGET_TRIPLE "\"+config.target_triple+\"")
+  endif()
+
+  string(CONCAT LIT_SITE_CFG_IN_FOOTER
+     "import lit.llvm\n"
+     "lit.llvm.initialize(lit_config, config)\n")
+
+  configure_file(${site_in} ${site_out} @ONLY)
+  if (EXISTS "${ARG_MAIN_CONFIG}")
+    set(PYTHON_STATEMENT "map_config('${ARG_MAIN_CONFIG}', '${site_out}')")
+    get_property(LLVM_LIT_CONFIG_MAP GLOBAL PROPERTY LLVM_LIT_CONFIG_MAP)
+    set(LLVM_LIT_CONFIG_MAP "${LLVM_LIT_CONFIG_MAP}\n${PYTHON_STATEMENT}")
+    set_property(GLOBAL PROPERTY LLVM_LIT_CONFIG_MAP ${LLVM_LIT_CONFIG_MAP})
+  endif()
+endfunction()
+
+function(dump_all_cmake_variables)
+  get_cmake_property(_variableNames VARIABLES)
+  foreach (_variableName ${_variableNames})
+    message(STATUS "${_variableName}=${${_variableName}}")
+  endforeach()
+endfunction()
+
+function(get_llvm_lit_path base_dir file_name)
+  cmake_parse_arguments(ARG "ALLOW_EXTERNAL" "" "" ${ARGN})
+
+  if (ARG_ALLOW_EXTERNAL)
+    set(LLVM_DEFAULT_EXTERNAL_LIT "${LLVM_EXTERNAL_LIT}")
+    set (LLVM_EXTERNAL_LIT "" CACHE STRING "Command used to spawn lit")
+    if ("${LLVM_EXTERNAL_LIT}" STREQUAL "")
+      set(LLVM_EXTERNAL_LIT "${LLVM_DEFAULT_EXTERNAL_LIT}")
+    endif()
+
+    if (NOT "${LLVM_EXTERNAL_LIT}" STREQUAL "")
+      if (EXISTS ${LLVM_EXTERNAL_LIT})
+        get_filename_component(LIT_FILE_NAME ${LLVM_EXTERNAL_LIT} NAME)
+        get_filename_component(LIT_BASE_DIR ${LLVM_EXTERNAL_LIT} DIRECTORY)
+        set(${file_name} ${LIT_FILE_NAME} PARENT_SCOPE)
+        set(${base_dir} ${LIT_BASE_DIR} PARENT_SCOPE)
+        return()
+      else()
+        message(WARN "LLVM_EXTERNAL_LIT set to ${LLVM_EXTERNAL_LIT}, but the path does not exist.")
+      endif()
+    endif()
+  endif()
+
+  set(lit_file_name "llvm-lit")
+  if (WIN32 AND NOT CYGWIN)
+    # llvm-lit needs suffix.py for multiprocess to find a main module.
+    set(lit_file_name "${lit_file_name}.py")
+  endif ()
+  set(${file_name} ${lit_file_name} PARENT_SCOPE)
+
+  get_property(LLVM_LIT_BASE_DIR GLOBAL PROPERTY LLVM_LIT_BASE_DIR)
+  if (NOT "${LLVM_LIT_BASE_DIR}" STREQUAL "")
+    set(${base_dir} ${LLVM_LIT_BASE_DIR} PARENT_SCOPE)
+  endif()
+
+  # Allow individual projects to provide an override
+  if (NOT "${LLVM_LIT_OUTPUT_DIR}" STREQUAL "")
+    set(LLVM_LIT_BASE_DIR ${LLVM_LIT_OUTPUT_DIR})
+  elseif(NOT "${LLVM_RUNTIME_OUTPUT_INTDIR}" STREQUAL "")
+    set(LLVM_LIT_BASE_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
+  else()
+    set(LLVM_LIT_BASE_DIR "")
+  endif()
+
+  # Cache this so we don't have to do it again and have subsequent calls
+  # potentially disagree on the value.
+  set_property(GLOBAL PROPERTY LLVM_LIT_BASE_DIR ${LLVM_LIT_BASE_DIR})
+  set(${base_dir} ${LLVM_LIT_BASE_DIR} PARENT_SCOPE)
+endfunction()
+
+# A raw function to create a lit target. This is used to implement the testuite
+# management functions.
+function(add_lit_target target comment)
+  cmake_parse_arguments(ARG "" "" "PARAMS;DEPENDS;ARGS" ${ARGN})
+  set(LIT_ARGS "${ARG_ARGS} ${LLVM_LIT_ARGS}")
+  separate_arguments(LIT_ARGS)
+  if (NOT CMAKE_CFG_INTDIR STREQUAL ".")
+    list(APPEND LIT_ARGS --param build_mode=${CMAKE_CFG_INTDIR})
+  endif ()
+
+  # Get the path to the lit to *run* tests with.  This can be overriden by
+  # the user by specifying -DLLVM_EXTERNAL_LIT=<path-to-lit.py>
+  get_llvm_lit_path(
+    lit_base_dir
+    lit_file_name
+    ALLOW_EXTERNAL
+    )
+
+  set(LIT_COMMAND "${PYTHON_EXECUTABLE};${lit_base_dir}/${lit_file_name}")
+  list(APPEND LIT_COMMAND ${LIT_ARGS})
+  foreach(param ${ARG_PARAMS})
+    list(APPEND LIT_COMMAND --param ${param})
+  endforeach()
+  if (ARG_UNPARSED_ARGUMENTS)
+    add_custom_target(${target}
+      COMMAND ${LIT_COMMAND} ${ARG_UNPARSED_ARGUMENTS}
+      COMMENT "${comment}"
+      USES_TERMINAL
+      )
+  else()
+    add_custom_target(${target}
+      COMMAND ${CMAKE_COMMAND} -E echo "${target} does nothing, no tools built.")
+    message(STATUS "${target} does nothing.")
+  endif()
+  if (ARG_DEPENDS)
+    add_dependencies(${target} ${ARG_DEPENDS})
+  endif()
+
+  # Tests should be excluded from "Build Solution".
+  set_target_properties(${target} PROPERTIES EXCLUDE_FROM_DEFAULT_BUILD ON)
+endfunction()
+
+# A function to add a set of lit test suites to be driven through 'check-*' targets.
+function(add_lit_testsuite target comment)
+  cmake_parse_arguments(ARG "" "" "PARAMS;DEPENDS;ARGS" ${ARGN})
+
+  # EXCLUDE_FROM_ALL excludes the test ${target} out of check-all.
+  if(NOT EXCLUDE_FROM_ALL)
+    # Register the testsuites, params and depends for the global check rule.
+    set_property(GLOBAL APPEND PROPERTY LLVM_LIT_TESTSUITES ${ARG_UNPARSED_ARGUMENTS})
+    set_property(GLOBAL APPEND PROPERTY LLVM_LIT_PARAMS ${ARG_PARAMS})
+    set_property(GLOBAL APPEND PROPERTY LLVM_LIT_DEPENDS ${ARG_DEPENDS})
+    set_property(GLOBAL APPEND PROPERTY LLVM_LIT_EXTRA_ARGS ${ARG_ARGS})
+  endif()
+
+  # Produce a specific suffixed check rule.
+  add_lit_target(${target} ${comment}
+    ${ARG_UNPARSED_ARGUMENTS}
+    PARAMS ${ARG_PARAMS}
+    DEPENDS ${ARG_DEPENDS}
+    ARGS ${ARG_ARGS}
+    )
+endfunction()
+
+function(add_lit_testsuites project directory)
+  if (NOT CMAKE_CONFIGURATION_TYPES)
+    cmake_parse_arguments(ARG "" "" "PARAMS;DEPENDS;ARGS" ${ARGN})
+
+    # Search recursively for test directories by assuming anything not
+    # in a directory called Inputs contains tests.
+    file(GLOB_RECURSE to_process LIST_DIRECTORIES true ${directory}/*)
+    foreach(lit_suite ${to_process})
+      if(NOT IS_DIRECTORY ${lit_suite})
+        continue()
+      endif()
+      string(FIND ${lit_suite} Inputs is_inputs)
+      string(FIND ${lit_suite} Output is_output)
+      if (NOT (is_inputs EQUAL -1 AND is_output EQUAL -1))
+        continue()
+      endif()
+
+      # Create a check- target for the directory.
+      string(REPLACE ${directory} "" name_slash ${lit_suite})
+      if (name_slash)
+        string(REPLACE "/" "-" name_slash ${name_slash})
+        string(REPLACE "\\" "-" name_dashes ${name_slash})
+        string(TOLOWER "${project}${name_dashes}" name_var)
+        add_lit_target("check-${name_var}" "Running lit suite ${lit_suite}"
+          ${lit_suite}
+          PARAMS ${ARG_PARAMS}
+          DEPENDS ${ARG_DEPENDS}
+          ARGS ${ARG_ARGS}
+        )
+      endif()
+    endforeach()
+  endif()
+endfunction()
+
+function(llvm_install_library_symlink name dest type)
+  cmake_parse_arguments(ARG "ALWAYS_GENERATE" "COMPONENT" "" ${ARGN})
+  foreach(path ${CMAKE_MODULE_PATH})
+    if(EXISTS ${path}/LLVMInstallSymlink.cmake)
+      set(INSTALL_SYMLINK ${path}/LLVMInstallSymlink.cmake)
+      break()
+    endif()
+  endforeach()
+
+  set(component ${ARG_COMPONENT})
+  if(NOT component)
+    set(component ${name})
+  endif()
+
+  set(full_name ${CMAKE_${type}_LIBRARY_PREFIX}${name}${CMAKE_${type}_LIBRARY_SUFFIX})
+  set(full_dest ${CMAKE_${type}_LIBRARY_PREFIX}${dest}${CMAKE_${type}_LIBRARY_SUFFIX})
+
+  set(output_dir lib${LLVM_LIBDIR_SUFFIX})
+  if(WIN32 AND "${type}" STREQUAL "SHARED")
+    set(output_dir bin)
+  endif()
+
+  install(SCRIPT ${INSTALL_SYMLINK}
+          CODE "install_symlink(${full_name} ${full_dest} ${output_dir})"
+          COMPONENT ${component})
+
+  if (NOT CMAKE_CONFIGURATION_TYPES AND NOT ARG_ALWAYS_GENERATE)
+    add_llvm_install_targets(install-${name}
+                             DEPENDS ${name} ${dest} install-${dest}
+                             COMPONENT ${name})
+  endif()
+endfunction()
+
+function(llvm_install_symlink name dest)
+  cmake_parse_arguments(ARG "ALWAYS_GENERATE" "COMPONENT" "" ${ARGN})
+  foreach(path ${CMAKE_MODULE_PATH})
+    if(EXISTS ${path}/LLVMInstallSymlink.cmake)
+      set(INSTALL_SYMLINK ${path}/LLVMInstallSymlink.cmake)
+      break()
+    endif()
+  endforeach()
+
+  if(ARG_COMPONENT)
+    set(component ${ARG_COMPONENT})
+  else()
+    if(ARG_ALWAYS_GENERATE)
+      set(component ${dest})
+    else()
+      set(component ${name})
+    endif()
+  endif()
+
+  set(full_name ${name}${CMAKE_EXECUTABLE_SUFFIX})
+  set(full_dest ${dest}${CMAKE_EXECUTABLE_SUFFIX})
+
+  install(SCRIPT ${INSTALL_SYMLINK}
+          CODE "install_symlink(${full_name} ${full_dest} ${LLVM_TOOLS_INSTALL_DIR})"
+          COMPONENT ${component})
+
+  if (NOT CMAKE_CONFIGURATION_TYPES AND NOT ARG_ALWAYS_GENERATE)
+    add_llvm_install_targets(install-${name}
+                             DEPENDS ${name} ${dest} install-${dest}
+                             COMPONENT ${name})
+  endif()
+endfunction()
+
+function(add_llvm_tool_symlink link_name target)
+  cmake_parse_arguments(ARG "ALWAYS_GENERATE" "OUTPUT_DIR" "" ${ARGN})
+  set(dest_binary "$<TARGET_FILE:${target}>")
+
+  # This got a bit gross... For multi-configuration generators the target
+  # properties return the resolved value of the string, not the build system
+  # expression. To reconstruct the platform-agnostic path we have to do some
+  # magic. First we grab one of the types, and a type-specific path. Then from
+  # the type-specific path we find the last occurrence of the type in the path,
+  # and replace it with CMAKE_CFG_INTDIR. This allows the build step to be type
+  # agnostic again.
+  if(NOT ARG_OUTPUT_DIR)
+    # If you're not overriding the OUTPUT_DIR, we can make the link relative in
+    # the same directory.
+    if(CMAKE_HOST_UNIX)
+      set(dest_binary "$<TARGET_FILE_NAME:${target}>")
+    endif()
+    if(CMAKE_CONFIGURATION_TYPES)
+      list(GET CMAKE_CONFIGURATION_TYPES 0 first_type)
+      string(TOUPPER ${first_type} first_type_upper)
+      set(first_type_suffix _${first_type_upper})
+    endif()
+    get_target_property(target_type ${target} TYPE)
+    if(${target_type} STREQUAL "STATIC_LIBRARY")
+      get_target_property(ARG_OUTPUT_DIR ${target} ARCHIVE_OUTPUT_DIRECTORY${first_type_suffix})
+    elseif(UNIX AND ${target_type} STREQUAL "SHARED_LIBRARY")
+      get_target_property(ARG_OUTPUT_DIR ${target} LIBRARY_OUTPUT_DIRECTORY${first_type_suffix})
+    else()
+      get_target_property(ARG_OUTPUT_DIR ${target} RUNTIME_OUTPUT_DIRECTORY${first_type_suffix})
+    endif()
+    if(CMAKE_CONFIGURATION_TYPES)
+      string(FIND "${ARG_OUTPUT_DIR}" "/${first_type}/" type_start REVERSE)
+      string(SUBSTRING "${ARG_OUTPUT_DIR}" 0 ${type_start} path_prefix)
+      string(SUBSTRING "${ARG_OUTPUT_DIR}" ${type_start} -1 path_suffix)
+      string(REPLACE "/${first_type}/" "/${CMAKE_CFG_INTDIR}/"
+             path_suffix ${path_suffix})
+      set(ARG_OUTPUT_DIR ${path_prefix}${path_suffix})
+    endif()
+  endif()
+
+  if(CMAKE_HOST_UNIX)
+    set(LLVM_LINK_OR_COPY create_symlink)
+  else()
+    set(LLVM_LINK_OR_COPY copy)
+  endif()
+
+  set(output_path "${ARG_OUTPUT_DIR}/${link_name}${CMAKE_EXECUTABLE_SUFFIX}")
+
+  set(target_name ${link_name})
+  if(TARGET ${link_name})
+    set(target_name ${link_name}-link)
+  endif()
+
+
+  if(ARG_ALWAYS_GENERATE)
+    set_property(DIRECTORY APPEND PROPERTY
+      ADDITIONAL_MAKE_CLEAN_FILES ${dest_binary})
+    add_custom_command(TARGET ${target} POST_BUILD
+      COMMAND ${CMAKE_COMMAND} -E ${LLVM_LINK_OR_COPY} "${dest_binary}" "${output_path}")
+  else()
+    add_custom_command(OUTPUT ${output_path}
+                     COMMAND ${CMAKE_COMMAND} -E ${LLVM_LINK_OR_COPY} "${dest_binary}" "${output_path}"
+                     DEPENDS ${target})
+    add_custom_target(${target_name} ALL DEPENDS ${target} ${output_path})
+    set_target_properties(${target_name} PROPERTIES FOLDER Tools)
+
+    # Make sure both the link and target are toolchain tools
+    if (${link_name} IN_LIST LLVM_TOOLCHAIN_TOOLS AND ${target} IN_LIST LLVM_TOOLCHAIN_TOOLS)
+      set(TOOL_IS_TOOLCHAIN ON)
+    endif()
+
+    if ((TOOL_IS_TOOLCHAIN OR NOT LLVM_INSTALL_TOOLCHAIN_ONLY) AND LLVM_BUILD_TOOLS)
+      llvm_install_symlink(${link_name} ${target})
+    endif()
+  endif()
+endfunction()
+
+function(llvm_externalize_debuginfo name)
+  if(NOT LLVM_EXTERNALIZE_DEBUGINFO)
+    return()
+  endif()
+
+  if(NOT LLVM_EXTERNALIZE_DEBUGINFO_SKIP_STRIP)
+    if(APPLE)
+      set(strip_command COMMAND xcrun strip -Sxl $<TARGET_FILE:${name}>)
+    else()
+      set(strip_command COMMAND strip -gx $<TARGET_FILE:${name}>)
+    endif()
+  endif()
+
+  if(APPLE)
+    if(CMAKE_CXX_FLAGS MATCHES "-flto"
+      OR CMAKE_CXX_FLAGS_${uppercase_CMAKE_BUILD_TYPE} MATCHES "-flto")
+
+      set(lto_object ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/${name}-lto.o)
+      set_property(TARGET ${name} APPEND_STRING PROPERTY
+        LINK_FLAGS " -Wl,-object_path_lto,${lto_object}")
+    endif()
+    add_custom_command(TARGET ${name} POST_BUILD
+      COMMAND xcrun dsymutil $<TARGET_FILE:${name}>
+      ${strip_command}
+      )
+  else()
+    add_custom_command(TARGET ${name} POST_BUILD
+      COMMAND objcopy --only-keep-debug $<TARGET_FILE:${name}> $<TARGET_FILE:${name}>.debug
+      ${strip_command} -R .gnu_debuglink
+      COMMAND objcopy --add-gnu-debuglink=$<TARGET_FILE:${name}>.debug $<TARGET_FILE:${name}>
+      )
+  endif()
+endfunction()
+
+function(llvm_setup_rpath name)
+  if(CMAKE_INSTALL_RPATH)
+    return()
+  endif()
+
+  if(LLVM_INSTALL_PREFIX AND NOT (LLVM_INSTALL_PREFIX STREQUAL CMAKE_INSTALL_PREFIX))
+    set(extra_libdir ${LLVM_LIBRARY_DIR})
+  elseif(LLVM_BUILD_LIBRARY_DIR)
+    set(extra_libdir ${LLVM_LIBRARY_DIR})
+  endif()
+
+  if (APPLE)
+    set(_install_name_dir INSTALL_NAME_DIR "@rpath")
+    set(_install_rpath "@loader_path/../lib" ${extra_libdir})
+  elseif(UNIX)
+    set(_install_rpath "\$ORIGIN/../lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
+    if(${CMAKE_SYSTEM_NAME} MATCHES "(FreeBSD|DragonFly)")
+      set_property(TARGET ${name} APPEND_STRING PROPERTY
+                   LINK_FLAGS " -Wl,-z,origin ")
+    endif()
+    if(LLVM_LINKER_IS_GNULD)
+      # $ORIGIN is not interpreted at link time by ld.bfd
+      set_property(TARGET ${name} APPEND_STRING PROPERTY
+                   LINK_FLAGS " -Wl,-rpath-link,${LLVM_LIBRARY_OUTPUT_INTDIR} ")
+    endif()
+  else()
+    return()
+  endif()
+
+  set_target_properties(${name} PROPERTIES
+                        BUILD_WITH_INSTALL_RPATH On
+                        INSTALL_RPATH "${_install_rpath}"
+                        ${_install_name_dir})
+endfunction()
+
+function(setup_dependency_debugging name)
+  if(NOT LLVM_DEPENDENCY_DEBUGGING)
+    return()
+  endif()
+
+  if("intrinsics_gen" IN_LIST ARGN)
+    return()
+  endif()
+
+  set(deny_attributes_gen "(deny file* (literal \"${LLVM_BINARY_DIR}/include/llvm/IR/Attributes.gen\"))")
+  set(deny_intrinsics_gen "(deny file* (literal \"${LLVM_BINARY_DIR}/include/llvm/IR/Intrinsics.gen\"))")
+
+  set(sandbox_command "sandbox-exec -p '(version 1) (allow default) ${deny_attributes_gen} ${deny_intrinsics_gen}'")
+  set_target_properties(${name} PROPERTIES RULE_LAUNCH_COMPILE ${sandbox_command})
+endfunction()
+
+# Figure out if we can track VC revisions.
+function(find_first_existing_file out_var)
+  foreach(file ${ARGN})
+    if(EXISTS "${file}")
+      set(${out_var} "${file}" PARENT_SCOPE)
+      return()
+    endif()
+  endforeach()
+endfunction()
+
+macro(find_first_existing_vc_file out_var path)
+    find_program(git_executable NAMES git git.exe git.cmd)
+    # Run from a subdirectory to force git to print an absolute path.
+    execute_process(COMMAND ${git_executable} rev-parse --git-dir
+      WORKING_DIRECTORY ${path}/cmake
+      RESULT_VARIABLE git_result
+      OUTPUT_VARIABLE git_dir
+      ERROR_QUIET)
+    if(git_result EQUAL 0)
+      string(STRIP "${git_dir}" git_dir)
+      set(${out_var} "${git_dir}/logs/HEAD")
+      # some branchless cases (e.g. 'repo') may not yet have .git/logs/HEAD
+      if (NOT EXISTS "${git_dir}/logs/HEAD")
+        file(WRITE "${git_dir}/logs/HEAD" "")
+      endif()
+    else()
+      find_first_existing_file(${out_var}
+        "${path}/.svn/wc.db"   # SVN 1.7
+        "${path}/.svn/entries" # SVN 1.6
+      )
+    endif()
+endmacro()