diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -581,9 +581,10 @@
 option (LLVM_ENABLE_OCAMLDOC "Build OCaml bindings documentation." ON)
 option (LLVM_ENABLE_BINDINGS "Build bindings." ON)
 
-set(LLVM_INSTALL_DOXYGEN_HTML_DIR "share/doc/llvm/doxygen-html"
+include(GNUInstallDirs)
+set(LLVM_INSTALL_DOXYGEN_HTML_DIR "${CMAKE_INSTALL_DATADIR}/doc/llvm/doxygen-html"
     CACHE STRING "Doxygen-generated HTML documentation install directory")
-set(LLVM_INSTALL_OCAMLDOC_HTML_DIR "share/doc/llvm/ocaml-html"
+set(LLVM_INSTALL_OCAMLDOC_HTML_DIR "${CMAKE_INSTALL_DATADIR}/doc/llvm/ocaml-html"
     CACHE STRING "OCamldoc-generated HTML documentation install directory")
 
 option (LLVM_BUILD_EXTERNAL_COMPILER_RT
@@ -826,7 +827,7 @@
   include_directories(${TENSORFLOW_AOT_PATH}/include)
   add_subdirectory(${TENSORFLOW_AOT_PATH}/xla_aot_runtime_src
     ${CMAKE_ARCHIVE_OUTPUT_DIRECTORY}/tf_runtime)
-  install(TARGETS tf_xla_runtime EXPORT LLVMExports 
+  install(TARGETS tf_xla_runtime EXPORT LLVMExports
     ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT tf_xla_runtime)
   set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS tf_xla_runtime)
 endif()
diff --git a/llvm/cmake/modules/AddSphinxTarget.cmake b/llvm/cmake/modules/AddSphinxTarget.cmake
--- a/llvm/cmake/modules/AddSphinxTarget.cmake
+++ b/llvm/cmake/modules/AddSphinxTarget.cmake
@@ -1,3 +1,4 @@
+include(GNUInstallDirs)
 
 # Create sphinx target
 if (LLVM_ENABLE_SPHINX)
@@ -73,15 +74,10 @@
     # Handle installation
     if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
       if (builder STREQUAL man)
-        if (CMAKE_INSTALL_MANDIR)
-          set(INSTALL_MANDIR ${CMAKE_INSTALL_MANDIR}/)
-        else()
-          set(INSTALL_MANDIR share/man/)
-        endif()
         # FIXME: We might not ship all the tools that these man pages describe
         install(DIRECTORY "${SPHINX_BUILD_DIR}/" # Slash indicates contents of
                 COMPONENT "${project}-sphinx-man"
-                DESTINATION ${INSTALL_MANDIR}man1)
+                DESTINATION "${CMAKE_INSTALL_MANDIR}/man1")
 
         if(NOT LLVM_ENABLE_IDE)
           add_llvm_install_targets("install-${SPHINX_TARGET_NAME}"
@@ -90,7 +86,7 @@
         endif()
       elseif (builder STREQUAL html)
         string(TOUPPER "${project}" project_upper)
-        set(${project_upper}_INSTALL_SPHINX_HTML_DIR "share/doc/${project}/html"
+        set(${project_upper}_INSTALL_SPHINX_HTML_DIR "${CMAKE_INSTALL_DATADIR}/doc/${project}/html"
             CACHE STRING "HTML documentation install directory for ${project}")
 
         # '/.' indicates: copy the contents of the directory directly into