diff --git a/bolt/runtime/CMakeLists.txt b/bolt/runtime/CMakeLists.txt
--- a/bolt/runtime/CMakeLists.txt
+++ b/bolt/runtime/CMakeLists.txt
@@ -1,5 +1,6 @@
 cmake_minimum_required(VERSION 3.13.4)
 include(CheckIncludeFiles)
+include(GNUInstallDirs)
 
 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_CXX_STANDARD 14)
@@ -32,8 +33,8 @@
 target_compile_options(bolt_rt_hugify PRIVATE ${BOLT_RT_FLAGS})
 target_include_directories(bolt_rt_hugify PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
 
-install(TARGETS bolt_rt_instr DESTINATION lib)
-install(TARGETS bolt_rt_hugify DESTINATION lib)
+install(TARGETS bolt_rt_instr DESTINATION "${CMAKE_INSTALL_LIBDIR}")
+install(TARGETS bolt_rt_hugify DESTINATION "${CMAKE_INSTALL_LIBDIR}")
 
 if (CMAKE_CXX_COMPILER_ID MATCHES ".*Clang.*")
   add_library(bolt_rt_instr_osx STATIC
@@ -44,5 +45,5 @@
   target_compile_options(bolt_rt_instr_osx PRIVATE
     -target x86_64-apple-darwin19.6.0
     ${BOLT_RT_FLAGS})
-  install(TARGETS bolt_rt_instr_osx DESTINATION lib)
+  install(TARGETS bolt_rt_instr_osx DESTINATION "${CMAKE_INSTALL_LIBDIR}")
 endif()
diff --git a/clang/CMakeLists.txt b/clang/CMakeLists.txt
--- a/clang/CMakeLists.txt
+++ b/clang/CMakeLists.txt
@@ -97,7 +97,7 @@
 
   # They are used as destination of target generators.
   set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
+  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
   if(WIN32 OR CYGWIN)
     # DLL platform -- put DLLs into bin.
     set(LLVM_SHLIB_OUTPUT_INTDIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
@@ -132,8 +132,8 @@
   link_directories("${LLVM_LIBRARY_DIR}")
 
   set( CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin )
-  set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX} )
-  set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX} )
+  set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib )
+  set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib )
 
   if(LLVM_INCLUDE_TESTS)
     find_package(Python3 ${LLVM_MINIMUM_PYTHON_VERSION} REQUIRED
@@ -363,9 +363,6 @@
                       "LLVM_LINK_LLVM_DYLIB=OFF")
 endif()
 
-# The libdir suffix must exactly match whatever LLVM's configuration used.
-set(CLANG_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}")
-
 set(CLANG_TOOLS_INSTALL_DIR "${CMAKE_INSTALL_BINDIR}" CACHE PATH
     "Path for binary subdirectory (defaults to '${CMAKE_INSTALL_BINDIR}')")
 mark_as_advanced(CLANG_TOOLS_INSTALL_DIR)
@@ -926,6 +923,8 @@
   process_llvm_pass_plugins()
 endif()
 
+get_filename_component(CLANG_INSTALL_LIBDIR_BASENAME "${CMAKE_INSTALL_LIBDIR}" NAME)
+
 configure_file(
   ${CLANG_SOURCE_DIR}/include/clang/Config/config.h.cmake
   ${CLANG_BINARY_DIR}/include/clang/Config/config.h)
diff --git a/clang/cmake/caches/Android-stage2.cmake b/clang/cmake/caches/Android-stage2.cmake
--- a/clang/cmake/caches/Android-stage2.cmake
+++ b/clang/cmake/caches/Android-stage2.cmake
@@ -4,7 +4,7 @@
 set(CMAKE_BUILD_TYPE Release CACHE STRING "")
 set(LLVM_ENABLE_THREADS OFF CACHE BOOL "")
 set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
-set(LLVM_LIBDIR_SUFFIX 64 CACHE STRING "")
+set(CMAKE_INSTALL_LIBDIR "lib64" CACHE STRING "")
 set(LLVM_ENABLE_LIBCXX ON CACHE BOOL "")
 
 set(ANDROID_RUNTIMES_ENABLE_ASSERTIONS ON CACHE BOOL "")
diff --git a/clang/cmake/caches/Android.cmake b/clang/cmake/caches/Android.cmake
--- a/clang/cmake/caches/Android.cmake
+++ b/clang/cmake/caches/Android.cmake
@@ -13,7 +13,7 @@
 set(LLVM_BUILD_TOOLS OFF CACHE BOOL "")
 set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
 set(LLVM_ENABLE_THREADS OFF CACHE BOOL "")
-set(LLVM_LIBDIR_SUFFIX 64 CACHE STRING "")
+set(CMAKE_INSTALL_LIBDIR "lib64" CACHE STRING "")
 set(LLVM_TOOL_CLANG_TOOLS_EXTRA_BUILD OFF CACHE BOOL "")
 set(LLVM_TOOL_OPENMP_BUILD OFF CACHE BOOL "")
 set(LLVM_ENABLE_LIBCXX ON CACHE BOOL "")
diff --git a/clang/cmake/modules/AddClang.cmake b/clang/cmake/modules/AddClang.cmake
--- a/clang/cmake/modules/AddClang.cmake
+++ b/clang/cmake/modules/AddClang.cmake
@@ -119,8 +119,8 @@
         install(TARGETS ${lib}
           COMPONENT ${lib}
           ${export_to_clangtargets}
-          LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
-          ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+          LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+          ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
           RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
 
         if (NOT LLVM_ENABLE_IDE)
diff --git a/clang/cmake/modules/CMakeLists.txt b/clang/cmake/modules/CMakeLists.txt
--- a/clang/cmake/modules/CMakeLists.txt
+++ b/clang/cmake/modules/CMakeLists.txt
@@ -9,13 +9,13 @@
 set(CLANG_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/clang" CACHE STRING
   "Path for CMake subdirectory for Clang (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/clang')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(clang_cmake_builddir "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/clang")
+set(clang_cmake_builddir "${CMAKE_BINARY_DIR}/lib/cmake/clang")
 
 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
   "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
 
 get_property(CLANG_EXPORTS GLOBAL PROPERTY CLANG_EXPORTS)
 export(TARGETS ${CLANG_EXPORTS} FILE ${clang_cmake_builddir}/ClangTargets.cmake)
diff --git a/clang/include/clang/Config/config.h.cmake b/clang/include/clang/Config/config.h.cmake
--- a/clang/include/clang/Config/config.h.cmake
+++ b/clang/include/clang/Config/config.h.cmake
@@ -53,8 +53,8 @@
 /* Default architecture for SystemZ. */
 #define CLANG_SYSTEMZ_DEFAULT_ARCH "${CLANG_SYSTEMZ_DEFAULT_ARCH}"
 
-/* Multilib suffix for libdir. */
-#define CLANG_LIBDIR_SUFFIX "${CLANG_LIBDIR_SUFFIX}"
+/* Multilib basename for libdir. */
+#define CLANG_INSTALL_LIBDIR_BASENAME "${CLANG_INSTALL_LIBDIR_BASENAME}"
 
 /* Relative directory for resource files */
 #define CLANG_RESOURCE_DIR "${CLANG_RESOURCE_DIR}"
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -180,7 +180,7 @@
     // path of the embedding binary, which for LLVM binaries will be in bin/.
     // ../lib gets us to lib/ in both cases.
     P = llvm::sys::path::parent_path(Dir);
-    llvm::sys::path::append(P, Twine("lib") + CLANG_LIBDIR_SUFFIX, "clang",
+    llvm::sys::path::append(P, CLANG_INSTALL_LIBDIR_BASENAME, "clang",
                             CLANG_VERSION_STRING);
   }
 
diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -501,7 +501,8 @@
 
     SmallString<1024> Plugin;
     llvm::sys::path::native(
-        Twine(D.Dir) + "/../lib" CLANG_LIBDIR_SUFFIX "/LLVMgold" + Suffix,
+        Twine(D.Dir) + "/../" CLANG_INSTALL_LIBDIR_BASENAME "/LLVMgold" +
+            Suffix,
         Plugin);
     CmdArgs.push_back(Args.MakeArgString(Plugin));
   }
@@ -657,7 +658,7 @@
     // runtime
     SmallString<256> DefaultLibPath =
         llvm::sys::path::parent_path(TC.getDriver().Dir);
-    llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX);
+    llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
     CmdArgs.push_back("-rpath");
     CmdArgs.push_back(Args.MakeArgString(DefaultLibPath));
   }
@@ -670,7 +671,7 @@
   // runtime.
   SmallString<256> DefaultLibPath =
       llvm::sys::path::parent_path(TC.getDriver().Dir);
-  llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX);
+  llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
   CmdArgs.push_back(Args.MakeArgString("-L" + DefaultLibPath));
 }
 
@@ -1946,7 +1947,7 @@
 
   // Add path to lib-debug folders
   SmallString<256> DefaultLibPath = llvm::sys::path::parent_path(D.Dir);
-  llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX);
+  llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
   LibraryPaths.emplace_back(DefaultLibPath.c_str());
 
   // Build list of Static Device Libraries SDLs specified by -l option
@@ -2075,7 +2076,7 @@
 
   // Add path to clang lib / lib64 folder.
   SmallString<256> DefaultLibPath = llvm::sys::path::parent_path(D.Dir);
-  llvm::sys::path::append(DefaultLibPath, Twine("lib") + CLANG_LIBDIR_SUFFIX);
+  llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
   LibraryPaths.emplace_back(DefaultLibPath.c_str());
 
   // Add user defined library paths from LIBRARY_PATH.
diff --git a/clang/lib/Driver/ToolChains/Cuda.cpp b/clang/lib/Driver/ToolChains/Cuda.cpp
--- a/clang/lib/Driver/ToolChains/Cuda.cpp
+++ b/clang/lib/Driver/ToolChains/Cuda.cpp
@@ -592,7 +592,7 @@
   // Add paths for the default clang library path.
   SmallString<256> DefaultLibPath =
       llvm::sys::path::parent_path(TC.getDriver().Dir);
-  llvm::sys::path::append(DefaultLibPath, "lib" CLANG_LIBDIR_SUFFIX);
+  llvm::sys::path::append(DefaultLibPath, CLANG_INSTALL_LIBDIR_BASENAME);
   CmdArgs.push_back(Args.MakeArgString(Twine("-L") + DefaultLibPath));
 
   for (const auto &II : Inputs) {
diff --git a/clang/lib/Headers/CMakeLists.txt b/clang/lib/Headers/CMakeLists.txt
--- a/clang/lib/Headers/CMakeLists.txt
+++ b/clang/lib/Headers/CMakeLists.txt
@@ -420,7 +420,7 @@
 add_header_target("windows-resource-headers" ${windows_only_files})
 add_header_target("utility-resource-headers" ${utility_files})
 
-set(header_install_dir lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION}/include)
+set(header_install_dir ${CMAKE_INSTALL_LIBDIR}/clang/${CLANG_VERSION}/include)
 
 #############################################################
 # Install rules for the catch-all clang-resource-headers target
diff --git a/clang/runtime/CMakeLists.txt b/clang/runtime/CMakeLists.txt
--- a/clang/runtime/CMakeLists.txt
+++ b/clang/runtime/CMakeLists.txt
@@ -84,10 +84,12 @@
                -DLLVM_LIT_ARGS=${LLVM_LIT_ARGS}
                -DCOMPILER_RT_OUTPUT_DIR=${LLVM_LIBRARY_OUTPUT_INTDIR}/clang/${CLANG_VERSION}
                -DCOMPILER_RT_EXEC_OUTPUT_DIR=${LLVM_RUNTIME_OUTPUT_INTDIR}
-               -DCOMPILER_RT_INSTALL_PATH:PATH=lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION}
+               -DCOMPILER_RT_INSTALL_PATH:PATH=lib/clang/${CLANG_VERSION}
                -DCOMPILER_RT_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
-               -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
-               -DLLVM_LIBDIR_SUFFIX=${LLVM_LIBDIR_SUFFIX}
+               -DCMAKE_INSTALL_PREFIX="${CMAKE_INSTALL_PREFIX}"
+               -DCMAKE_INSTALL_BINDIR="${CMAKE_INSTALL_BINDIR}"
+               -DCMAKE_INSTALL_LIBDIR="${CMAKE_INSTALL_LIBDIR}"
+               -DCMAKE_INSTALL_INCLUDEDIR="${CMAKE_INSTALL_INCLUDEDIR}"
                -DLLVM_RUNTIME_OUTPUT_INTDIR=${LLVM_RUNTIME_OUTPUT_INTDIR}
                -DCMAKE_OSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET}
                -DCMAKE_OSX_SYSROOT:PATH=${CMAKE_OSX_SYSROOT}
diff --git a/clang/tools/libclang/CMakeLists.txt b/clang/tools/libclang/CMakeLists.txt
--- a/clang/tools/libclang/CMakeLists.txt
+++ b/clang/tools/libclang/CMakeLists.txt
@@ -180,7 +180,7 @@
           COMPONENT
             libclang-python-bindings
           DESTINATION
-            "lib${LLVM_LIBDIR_SUFFIX}/python${PythonVersion}/site-packages")
+            "${CMAKE_INSTALL_LIBDIR}/python${PythonVersion}/site-packages")
 endforeach()
 if(NOT LLVM_ENABLE_IDE)
   add_custom_target(libclang-python-bindings)
diff --git a/clang/tools/scan-build-py/CMakeLists.txt b/clang/tools/scan-build-py/CMakeLists.txt
--- a/clang/tools/scan-build-py/CMakeLists.txt
+++ b/clang/tools/scan-build-py/CMakeLists.txt
@@ -88,7 +88,7 @@
                      DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/lib/libscanbuild/${lib})
   list(APPEND Depends ${CMAKE_BINARY_DIR}/lib/libscanbuild/${lib})
   install(PROGRAMS lib/libscanbuild/${lib}
-          DESTINATION lib/libscanbuild
+          DESTINATION "${CMAKE_INSTALL_LIBDIR}/libscanbuild"
           COMPONENT scan-build-py)
 endforeach()
 
@@ -106,7 +106,7 @@
                      DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/lib/libscanbuild/resources/${resource})
   list(APPEND Depends ${CMAKE_BINARY_DIR}/lib/libscanbuild/resources/${resource})
   install(PROGRAMS lib/libscanbuild/resources/${resource}
-          DESTINATION lib/libscanbuild/resources
+          DESTINATION "${CMAKE_INSTALL_LIBDIR}/libscanbuild/resources"
           COMPONENT scan-build-py)
 endforeach()
 
@@ -122,7 +122,7 @@
                      DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/lib/libear/${lib})
   list(APPEND Depends ${CMAKE_BINARY_DIR}/lib/libear/${lib})
   install(PROGRAMS lib/libear/${lib}
-          DESTINATION lib/libear
+          DESTINATION "${CMAKE_INSTALL_LIBDIR}/libear"
           COMPONENT scan-build-py)
 endforeach()
 
diff --git a/cmake/Modules/GNUInstallPackageDir.cmake b/cmake/Modules/GNUInstallPackageDir.cmake
--- a/cmake/Modules/GNUInstallPackageDir.cmake
+++ b/cmake/Modules/GNUInstallPackageDir.cmake
@@ -29,5 +29,5 @@
   _GNUInstallPackageDir_cache_convert_to_path("${var}" "${description}")
 endmacro()
 
-_GNUInstallPackageDir_cache_path(CMAKE_INSTALL_PACKAGEDIR "lib${LLVM_LIBDIR_SUFFIX}/cmake"
+_GNUInstallPackageDir_cache_path(CMAKE_INSTALL_PACKAGEDIR "${CMAKE_INSTALL_LIBDIR}/cmake"
   "Directories containing installed CMake modules (lib/cmake)")
diff --git a/compiler-rt/cmake/Modules/CompilerRTAIXUtils.cmake b/compiler-rt/cmake/Modules/CompilerRTAIXUtils.cmake
--- a/compiler-rt/cmake/Modules/CompilerRTAIXUtils.cmake
+++ b/compiler-rt/cmake/Modules/CompilerRTAIXUtils.cmake
@@ -62,7 +62,7 @@
     # setting _install_rpath on AIX for reference.
     if(LLVM_LIBRARY_OUTPUT_INTDIR AND CMAKE_INSTALL_PREFIX)
       set(output_dir "${LLVM_LIBRARY_OUTPUT_INTDIR}")
-      set(install_dir "${CMAKE_INSTALL_PREFIX}/lib${LLVM_LIBDIR_SUFFIX}")
+      set(install_dir "${CMAKE_INSTALL_LIBDIR}")
     else()
       get_compiler_rt_output_dir(${COMPILER_RT_DEFAULT_TARGET_ARCH} output_dir)
       get_compiler_rt_install_dir(${COMPILER_RT_DEFAULT_TARGET_ARCH} install_dir)
diff --git a/compiler-rt/cmake/Modules/CompilerRTUtils.cmake b/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
--- a/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
+++ b/compiler-rt/cmake/Modules/CompilerRTUtils.cmake
@@ -377,7 +377,7 @@
       file(TO_CMAKE_PATH ${LLVM_CMAKE_DIR_FROM_LLVM_CONFIG} LLVM_CMAKE_DIR)
     else()
       file(TO_CMAKE_PATH ${LLVM_BINARY_DIR} LLVM_BINARY_DIR_CMAKE_STYLE)
-      set(LLVM_CMAKE_DIR "${LLVM_BINARY_DIR_CMAKE_STYLE}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
+      set(LLVM_CMAKE_DIR "${LLVM_BINARY_DIR_CMAKE_STYLE}/lib/cmake/llvm")
     endif()
 
     set(LLVM_CMAKE_INCLUDE_FILE "${LLVM_CMAKE_DIR}/LLVMConfig.cmake")
@@ -393,7 +393,7 @@
     unset(LLVM_CMAKE_INCLUDE_FILE)
 
     set(LLVM_LIBRARY_OUTPUT_INTDIR
-      ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
+      ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
   endif()
 
   # Finally set the cache variable now that `llvm-config` has also had a chance
diff --git a/compiler-rt/cmake/base-config-ix.cmake b/compiler-rt/cmake/base-config-ix.cmake
--- a/compiler-rt/cmake/base-config-ix.cmake
+++ b/compiler-rt/cmake/base-config-ix.cmake
@@ -45,7 +45,7 @@
   # Setup the paths where compiler-rt runtimes and headers should be stored.
   set(COMPILER_RT_OUTPUT_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/clang/${CLANG_VERSION})
   set(COMPILER_RT_EXEC_OUTPUT_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
-  set(COMPILER_RT_INSTALL_PATH lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION})
+  set(COMPILER_RT_INSTALL_PATH "${CMAKE_INSTALL_LIBDIR}/clang/${CLANG_VERSION}")
   option(COMPILER_RT_INCLUDE_TESTS "Generate and build compiler-rt unit tests."
          ${LLVM_INCLUDE_TESTS})
   option(COMPILER_RT_ENABLE_WERROR "Fail and stop if warning is triggered"
@@ -97,25 +97,30 @@
     string(TOLOWER ${CMAKE_SYSTEM_NAME} COMPILER_RT_OS_DIR)
   endif()
 endif()
+
 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
   set(COMPILER_RT_OUTPUT_LIBRARY_DIR
     ${COMPILER_RT_OUTPUT_DIR}/lib)
-  extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" lib)
-  set(COMPILER_RT_INSTALL_LIBRARY_DIR "${default_install_path}" CACHE PATH
-    "Path where built compiler-rt libraries should be installed.")
-else(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
+  # Don't use "${CMAKE_INSTALL_LIBDIR}", because the intended use-case is that
+  # "${COMPILER_RT_INSTALL_PATH}" is already non-trival and probably includes
+  # "${CMAKE_INSTALL_LIBDIR}".
+  extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "lib")
+else()
   set(COMPILER_RT_OUTPUT_LIBRARY_DIR
     ${COMPILER_RT_OUTPUT_DIR}/lib/${COMPILER_RT_OS_DIR})
-  extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "lib/${COMPILER_RT_OS_DIR}")
-  set(COMPILER_RT_INSTALL_LIBRARY_DIR "${default_install_path}" CACHE PATH
-    "Path where built compiler-rt libraries should be installed.")
+  extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "${CMAKE_INSTALL_LIBDIR}/${COMPILER_RT_OS_DIR}")
 endif()
+set(COMPILER_RT_INSTALL_LIBRARY_DIR "${default_install_path}" CACHE PATH
+  "Path where built compiler-rt libraries should be installed.")
+
 extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "${CMAKE_INSTALL_BINDIR}")
 set(COMPILER_RT_INSTALL_BINARY_DIR "${default_install_path}" CACHE PATH
   "Path where built compiler-rt executables should be installed.")
+
 extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "${CMAKE_INSTALL_INCLUDEDIR}")
 set(COMPILER_RT_INSTALL_INCLUDE_DIR "${default_install_path}" CACHE PATH
   "Path where compiler-rt headers should be installed.")
+
 extend_path(default_install_path "${COMPILER_RT_INSTALL_PATH}" "${CMAKE_INSTALL_DATADIR}")
 set(COMPILER_RT_INSTALL_DATA_DIR "${default_install_path}" CACHE PATH
   "Path where compiler-rt data files should be installed.")
diff --git a/compiler-rt/docs/BuildingCompilerRT.rst b/compiler-rt/docs/BuildingCompilerRT.rst
--- a/compiler-rt/docs/BuildingCompilerRT.rst
+++ b/compiler-rt/docs/BuildingCompilerRT.rst
@@ -79,14 +79,3 @@
 
   Path where Compiler-RT data should be installed. If a relative
   path, relative to ``COMPILER_RT_INSTALL_PATH``.
-
-.. _LLVM-specific variables:
-
-LLVM-specific options
----------------------
-
-.. option:: LLVM_LIBDIR_SUFFIX:STRING
-
-  Extra suffix to append to the directory where libraries are to be
-  installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64``
-  to install libraries to ``/usr/lib64``.
diff --git a/flang/CMakeLists.txt b/flang/CMakeLists.txt
--- a/flang/CMakeLists.txt
+++ b/flang/CMakeLists.txt
@@ -129,9 +129,9 @@
 
   set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
   set(CMAKE_LIBRARY_OUTPUT_DIRECTORY
-    ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
+    ${CMAKE_BINARY_DIR}/lib)
   set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY
-    ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
+    ${CMAKE_BINARY_DIR}/lib)
 
   set(BACKEND_PACKAGE_STRING "LLVM ${LLVM_PACKAGE_VERSION}")
   set(LLVM_EXTERNAL_LIT "${LLVM_TOOLS_BINARY_DIR}/llvm-lit" CACHE STRING "Command used to spawn lit")
diff --git a/flang/cmake/modules/AddFlang.cmake b/flang/cmake/modules/AddFlang.cmake
--- a/flang/cmake/modules/AddFlang.cmake
+++ b/flang/cmake/modules/AddFlang.cmake
@@ -70,8 +70,8 @@
       install(TARGETS ${name}
         COMPONENT ${name}
         ${export_to_flangtargets}
-        LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
-        ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+        LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+        ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
         RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
 
       if (NOT LLVM_ENABLE_IDE)
diff --git a/flang/cmake/modules/CMakeLists.txt b/flang/cmake/modules/CMakeLists.txt
--- a/flang/cmake/modules/CMakeLists.txt
+++ b/flang/cmake/modules/CMakeLists.txt
@@ -8,13 +8,13 @@
 set(FLANG_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/flang" CACHE STRING
   "Path for CMake subdirectory for Flang (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/flang')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(flang_cmake_builddir "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/flang")
+set(flang_cmake_builddir "${CMAKE_BINARY_DIR}/lib/cmake/flang")
 
 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
   "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
 
 get_property(FLANG_EXPORTS GLOBAL PROPERTY FLANG_EXPORTS)
 export(TARGETS ${FLANG_EXPORTS} FILE ${flang_cmake_builddir}/FlangTargets.cmake)
diff --git a/libc/CMakeLists.txt b/libc/CMakeLists.txt
--- a/libc/CMakeLists.txt
+++ b/libc/CMakeLists.txt
@@ -1,5 +1,7 @@
 cmake_minimum_required(VERSION 3.13.4)
 
+include(GNUInstallDirs)
+
 # Default to C++17
 set(CMAKE_CXX_STANDARD 17)
 
diff --git a/libc/lib/CMakeLists.txt b/libc/lib/CMakeLists.txt
--- a/libc/lib/CMakeLists.txt
+++ b/libc/lib/CMakeLists.txt
@@ -5,9 +5,9 @@
 )
 
 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR)
-  set(LIBC_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE})
+  set(LIBC_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
 else()
-  set(LIBC_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX})
+  set(LIBC_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR})
 endif()
 
 install(
diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -151,8 +151,6 @@
 endif()
 
 option(LIBCXX_INCLUDE_DOCS "Build the libc++ documentation." ${LLVM_INCLUDE_DOCS})
-set(LIBCXX_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
-    "Define suffix of library directory name (32/64)")
 option(LIBCXX_INSTALL_HEADERS "Install the libc++ headers." ON)
 option(LIBCXX_INSTALL_LIBRARY "Install the libc++ library." ON)
 cmake_dependent_option(LIBCXX_INSTALL_STATIC_LIBRARY
@@ -419,7 +417,7 @@
   set(LIBCXX_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
   set(LIBCXX_GENERATED_INCLUDE_DIR "${LLVM_BINARY_DIR}/include/c++/v1")
   set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LLVM_BINARY_DIR}/include/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1")
-  set(LIBCXX_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
+  set(LIBCXX_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
       "Path where built libc++ libraries should be installed.")
   set(LIBCXX_INSTALL_INCLUDE_TARGET_DIR "${CMAKE_INSTALL_INCLUDEDIR}/${LLVM_DEFAULT_TARGET_TRIPLE}/c++/v1" CACHE PATH
       "Path where target-specific libc++ headers should be installed.")
@@ -432,11 +430,11 @@
     set(LIBCXX_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
     set(LIBCXX_GENERATED_INCLUDE_DIR "${LLVM_BINARY_DIR}/include/c++/v1")
   else()
-    set(LIBCXX_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXX_LIBDIR_SUFFIX})
+    set(LIBCXX_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib)
     set(LIBCXX_GENERATED_INCLUDE_DIR "${CMAKE_BINARY_DIR}/include/c++/v1")
   endif()
   set(LIBCXX_GENERATED_INCLUDE_TARGET_DIR "${LIBCXX_GENERATED_INCLUDE_DIR}")
-  set(LIBCXX_INSTALL_LIBRARY_DIR lib${LIBCXX_LIBDIR_SUFFIX} CACHE PATH
+  set(LIBCXX_INSTALL_LIBRARY_DIR "${CMAKE_INSTALL_LIBDIR}" CACHE PATH
       "Path where built libc++ libraries should be installed.")
   set(LIBCXX_INSTALL_INCLUDE_TARGET_DIR "${LIBCXX_INSTALL_INCLUDE_DIR}" CACHE PATH
       "Path where target-specific libc++ headers should be installed.")
diff --git a/libcxx/docs/BuildingLibcxx.rst b/libcxx/docs/BuildingLibcxx.rst
--- a/libcxx/docs/BuildingLibcxx.rst
+++ b/libcxx/docs/BuildingLibcxx.rst
@@ -235,11 +235,6 @@
   Build libc++ as a static library. Either `LIBCXX_ENABLE_SHARED` or
   `LIBCXX_ENABLE_STATIC` has to be enabled.
 
-.. option:: LIBCXX_LIBDIR_SUFFIX:STRING
-
-  Extra suffix to append to the directory where libraries are to be installed.
-  This option overrides `LLVM_LIBDIR_SUFFIX`.
-
 .. option:: LIBCXX_HERMETIC_STATIC_LIBRARY:BOOL
 
   **Default**: ``OFF``
@@ -267,7 +262,7 @@
 
 .. option:: LIBCXX_INSTALL_LIBRARY_DIR:PATH
 
-  **Default**: ``lib${LIBCXX_LIBDIR_SUFFIX}``
+  **Default**: ``lib``
 
   Path where built libc++ libraries should be installed. If a relative path,
   relative to ``CMAKE_INSTALL_PREFIX``.
@@ -430,12 +425,6 @@
 LLVM-specific options
 ---------------------
 
-.. option:: LLVM_LIBDIR_SUFFIX:STRING
-
-  Extra suffix to append to the directory where libraries are to be
-  installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64``
-  to install libraries to ``/usr/lib64``.
-
 .. option:: LLVM_BUILD_32_BITS:BOOL
 
   Build 32-bits executables and libraries on 64-bits systems. This option is
diff --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@@ -74,8 +74,6 @@
 endif()
 
 option(LIBCXXABI_INCLUDE_TESTS "Generate build targets for the libc++abi unit tests." ${LLVM_INCLUDE_TESTS})
-set(LIBCXXABI_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
-    "Define suffix of library directory name (32/64)")
 option(LIBCXXABI_INSTALL_HEADERS "Install the libc++abi headers." ON)
 option(LIBCXXABI_INSTALL_LIBRARY "Install the libc++abi library." ON)
 
@@ -187,7 +185,7 @@
 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
   set(LIBCXXABI_HEADER_DIR ${LLVM_BINARY_DIR})
   set(LIBCXXABI_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
-  set(LIBCXXABI_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
+  set(LIBCXXABI_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
       "Path where built libc++abi libraries should be installed.")
   if(LIBCXX_LIBDIR_SUBDIR)
     string(APPEND LIBCXXABI_LIBRARY_DIR /${LIBCXXABI_LIBDIR_SUBDIR})
@@ -199,9 +197,9 @@
     set(LIBCXXABI_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
   else()
     set(LIBCXXABI_HEADER_DIR ${CMAKE_BINARY_DIR})
-    set(LIBCXXABI_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBCXXABI_LIBDIR_SUFFIX})
+    set(LIBCXXABI_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib)
   endif()
-  set(LIBCXXABI_INSTALL_LIBRARY_DIR lib${LIBCXXABI_LIBDIR_SUFFIX} CACHE PATH
+  set(LIBCXXABI_INSTALL_LIBRARY_DIR "${CMAKE_INSTALL_LIBDIR}" CACHE PATH
       "Path where built libc++abi libraries should be installed.")
 endif()
 
diff --git a/libunwind/CMakeLists.txt b/libunwind/CMakeLists.txt
--- a/libunwind/CMakeLists.txt
+++ b/libunwind/CMakeLists.txt
@@ -51,8 +51,6 @@
 option(LIBUNWIND_REMEMBER_HEAP_ALLOC "Use heap instead of the stack for .cfi_remember_state." OFF)
 option(LIBUNWIND_INSTALL_HEADERS "Install the libunwind headers." OFF)
 
-set(LIBUNWIND_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}" CACHE STRING
-    "Define suffix of library directory name (32/64)")
 option(LIBUNWIND_INSTALL_LIBRARY "Install the libunwind library." ON)
 cmake_dependent_option(LIBUNWIND_INSTALL_STATIC_LIBRARY
   "Install the static libunwind library." ON
@@ -117,7 +115,7 @@
 
 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
   set(LIBUNWIND_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE})
-  set(LIBUNWIND_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
+  set(LIBUNWIND_INSTALL_LIBRARY_DIR ${CMAKE_INSTALL_LIBDIR}/${LLVM_DEFAULT_TARGET_TRIPLE} CACHE PATH
       "Path where built libunwind libraries should be installed.")
   if(LIBCXX_LIBDIR_SUBDIR)
     string(APPEND LIBUNWIND_LIBRARY_DIR /${LIBUNWIND_LIBDIR_SUBDIR})
@@ -127,9 +125,9 @@
   if(LLVM_LIBRARY_OUTPUT_INTDIR)
     set(LIBUNWIND_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
   else()
-    set(LIBUNWIND_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBUNWIND_LIBDIR_SUFFIX})
+    set(LIBUNWIND_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib)
   endif()
-  set(LIBUNWIND_INSTALL_LIBRARY_DIR lib${LIBUNWIND_LIBDIR_SUFFIX} CACHE PATH
+  set(LIBUNWIND_INSTALL_LIBRARY_DIR "${CMAKE_INSTALL_LIBDIR}" CACHE PATH
       "Path where built libunwind libraries should be installed.")
 endif()
 
diff --git a/libunwind/docs/BuildingLibunwind.rst b/libunwind/docs/BuildingLibunwind.rst
--- a/libunwind/docs/BuildingLibunwind.rst
+++ b/libunwind/docs/BuildingLibunwind.rst
@@ -144,7 +144,7 @@
 
 .. option:: LIBUNWIND_INSTALL_LIBRARY_DIR:PATH
 
-  **Default**: ``lib${LIBUNWIND_LIBDIR_SUFFIX}``
+  **Default**: ``lib``
 
   Path where built libunwind libraries should be installed. If a relative path,
   relative to ``CMAKE_INSTALL_PREFIX``.
diff --git a/lld/CMakeLists.txt b/lld/CMakeLists.txt
--- a/lld/CMakeLists.txt
+++ b/lld/CMakeLists.txt
@@ -85,7 +85,7 @@
 
   # They are used as destination of target generators.
   set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
+  set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
 
   include(AddLLVM)
   include(TableGen)
diff --git a/lld/cmake/modules/AddLLD.cmake b/lld/cmake/modules/AddLLD.cmake
--- a/lld/cmake/modules/AddLLD.cmake
+++ b/lld/cmake/modules/AddLLD.cmake
@@ -18,8 +18,8 @@
     install(TARGETS ${name}
       COMPONENT ${name}
       ${export_to_lldtargets}
-      LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
-      ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+      LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+      ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
       RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
 
     if (${ARG_SHARED} AND NOT CMAKE_CONFIGURATION_TYPES)
diff --git a/lld/cmake/modules/CMakeLists.txt b/lld/cmake/modules/CMakeLists.txt
--- a/lld/cmake/modules/CMakeLists.txt
+++ b/lld/cmake/modules/CMakeLists.txt
@@ -8,13 +8,13 @@
 set(LLD_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/lld" CACHE STRING
   "Path for CMake subdirectory for LLD (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/lld')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(lld_cmake_builddir "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/lld")
+set(lld_cmake_builddir "${CMAKE_BINARY_DIR}/lib/cmake/lld")
 
 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
   "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
 
 get_property(LLD_EXPORTS GLOBAL PROPERTY LLD_EXPORTS)
 export(TARGETS ${LLD_EXPORTS} FILE ${lld_cmake_builddir}/LLDTargets.cmake)
diff --git a/lldb/cmake/modules/AddLLDB.cmake b/lldb/cmake/modules/AddLLDB.cmake
--- a/lldb/cmake/modules/AddLLDB.cmake
+++ b/lldb/cmake/modules/AddLLDB.cmake
@@ -109,7 +109,7 @@
   endif()
 
   if(PARAM_SHARED)
-    set(install_dest lib${LLVM_LIBDIR_SUFFIX})
+    set(install_dest "${CMAKE_INSTALL_LIBDIR}")
     if(PARAM_INSTALL_PREFIX)
       set(install_dest ${PARAM_INSTALL_PREFIX})
     endif()
diff --git a/lldb/cmake/modules/LLDBConfig.cmake b/lldb/cmake/modules/LLDBConfig.cmake
--- a/lldb/cmake/modules/LLDBConfig.cmake
+++ b/lldb/cmake/modules/LLDBConfig.cmake
@@ -276,7 +276,7 @@
   # could be and pick the first that exists.
   foreach(CANDIDATE "${Clang_DIR}/../.." "${LLVM_DIR}" "${LLVM_LIBRARY_DIRS}"
                     "${LLVM_BUILD_LIBRARY_DIR}"
-                    "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}")
+                    "${LLVM_BINARY_DIR}/lib")
     # Build the resource directory path by appending 'clang/<version number>'.
     set(CANDIDATE_RESOURCE_DIR "${CANDIDATE}/clang/${LLDB_CLANG_RESOURCE_DIR_NAME}")
     if (IS_DIRECTORY "${CANDIDATE_RESOURCE_DIR}")
diff --git a/lldb/cmake/modules/LLDBGenerateConfig.cmake b/lldb/cmake/modules/LLDBGenerateConfig.cmake
--- a/lldb/cmake/modules/LLDBGenerateConfig.cmake
+++ b/lldb/cmake/modules/LLDBGenerateConfig.cmake
@@ -19,6 +19,8 @@
 
 check_library_exists(compression compression_encode_buffer "" HAVE_LIBCOMPRESSION)
 
+get_filename_component(LLDB_INSTALL_LIBDIR_BASENAME "${CMAKE_INSTALL_LIBDIR}" NAME)
+
 # These checks exist in LLVM's configuration, so I want to match the LLVM names
 # so that the check isn't duplicated, but we translate them into the LLDB names
 # so that I don't have to change all the uses at the moment.
diff --git a/lldb/cmake/modules/LLDBStandalone.cmake b/lldb/cmake/modules/LLDBStandalone.cmake
--- a/lldb/cmake/modules/LLDBStandalone.cmake
+++ b/lldb/cmake/modules/LLDBStandalone.cmake
@@ -76,7 +76,7 @@
 
 # They are used as destination of target generators.
 set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
+set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
 if(WIN32 OR CYGWIN)
   # DLL platform -- put DLLs into bin.
   set(LLVM_SHLIB_OUTPUT_INTDIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
@@ -116,5 +116,5 @@
 endif()
 
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
-set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
-set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX})
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
diff --git a/lldb/include/lldb/Host/Config.h.cmake b/lldb/include/lldb/Host/Config.h.cmake
--- a/lldb/include/lldb/Host/Config.h.cmake
+++ b/lldb/include/lldb/Host/Config.h.cmake
@@ -51,7 +51,7 @@
 
 #cmakedefine LLDB_PYTHON_HOME R"(${LLDB_PYTHON_HOME})"
 
-#define LLDB_LIBDIR_SUFFIX "${LLVM_LIBDIR_SUFFIX}"
+#define LLDB_INSTALL_LIBDIR_BASENAME "${LLDB_INSTALL_LIBDIR_BASENAME}"
 
 #cmakedefine LLDB_GLOBAL_INIT_DIRECTORY R"(${LLDB_GLOBAL_INIT_DIRECTORY})"
 
diff --git a/lldb/source/API/CMakeLists.txt b/lldb/source/API/CMakeLists.txt
--- a/lldb/source/API/CMakeLists.txt
+++ b/lldb/source/API/CMakeLists.txt
@@ -1,3 +1,5 @@
+include(ExtendPath)
+
 get_property(LLDB_ALL_PLUGINS GLOBAL PROPERTY LLDB_PLUGINS)
 
 if(LLDB_BUILD_FRAMEWORK)
@@ -113,7 +115,8 @@
 # (LLVM_LINK_LLVM_DYLIB). Add an additional rpath $ORIGIN/../../../../lib so
 # that _lldb.so can be loaded from Python.
 if(LLDB_ENABLE_PYTHON AND (BUILD_SHARED_LIBS OR LLVM_LINK_LLVM_DYLIB) AND UNIX AND NOT APPLE)
-  set_property(TARGET liblldb APPEND PROPERTY INSTALL_RPATH "\$ORIGIN/../../../../lib${LLVM_LIBDIR_SUFFIX}")
+  extend_path(install_rpath "\$ORIGIN/../../../../" "${CMAKE_INSTALL_LIBDIR}")
+  set_property(TARGET liblldb APPEND PROPERTY INSTALL_RPATH "${install_rpath}")
 endif()
 
 if(Python3_RPATH)
diff --git a/lldb/source/Host/linux/HostInfoLinux.cpp b/lldb/source/Host/linux/HostInfoLinux.cpp
--- a/lldb/source/Host/linux/HostInfoLinux.cpp
+++ b/lldb/source/Host/linux/HostInfoLinux.cpp
@@ -176,7 +176,7 @@
 }
 
 bool HostInfoLinux::ComputeSystemPluginsDirectory(FileSpec &file_spec) {
-  FileSpec temp_file("/usr/lib" LLDB_LIBDIR_SUFFIX "/lldb/plugins");
+  FileSpec temp_file("/usr/" LLDB_INSTALL_LIBDIR_BASENAME "/lldb/plugins");
   FileSystem::Instance().Resolve(temp_file);
   file_spec.GetDirectory().SetCString(temp_file.GetPath().c_str());
   return true;
diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangHost.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangHost.cpp
--- a/lldb/source/Plugins/ExpressionParser/Clang/ClangHost.cpp
+++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangHost.cpp
@@ -55,11 +55,11 @@
   static const llvm::StringRef kResourceDirSuffixes[] = {
       // LLVM.org's build of LLDB uses the clang resource directory placed
       // in $install_dir/lib{,64}/clang/$clang_version.
-      "lib" CLANG_LIBDIR_SUFFIX "/clang/" CLANG_VERSION_STRING,
+      CLANG_INSTALL_LIBDIR_BASENAME "/clang/" CLANG_VERSION_STRING,
       // swift-lldb uses the clang resource directory copied from swift, which
       // by default is placed in $install_dir/lib{,64}/lldb/clang. LLDB places
-      // it there, so we use LLDB_LIBDIR_SUFFIX.
-      "lib" LLDB_LIBDIR_SUFFIX "/lldb/clang",
+      // it there, so we use LLDB_INSTALL_LIBDIR_BASENAME.
+      LLDB_INSTALL_LIBDIR_BASENAME "/lldb/clang",
   };
 
   for (const auto &Suffix : kResourceDirSuffixes) {
diff --git a/lldb/tools/intel-features/CMakeLists.txt b/lldb/tools/intel-features/CMakeLists.txt
--- a/lldb/tools/intel-features/CMakeLists.txt
+++ b/lldb/tools/intel-features/CMakeLists.txt
@@ -30,4 +30,4 @@
   )
 
 install(TARGETS lldbIntelFeatures
-  LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX})
+  LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}")
diff --git a/lldb/unittests/Expression/ClangParserTest.cpp b/lldb/unittests/Expression/ClangParserTest.cpp
--- a/lldb/unittests/Expression/ClangParserTest.cpp
+++ b/lldb/unittests/Expression/ClangParserTest.cpp
@@ -37,7 +37,8 @@
 TEST_F(ClangHostTest, ComputeClangResourceDirectory) {
 #if !defined(_WIN32)
   std::string path_to_liblldb = "/foo/bar/lib/";
-  std::string path_to_clang_dir = "/foo/bar/lib" LLDB_LIBDIR_SUFFIX "/clang/" CLANG_VERSION_STRING;
+  std::string path_to_clang_dir =
+      "/foo/bar/" LLDB_INSTALL_LIBDIR_BASENAME "/clang/" CLANG_VERSION_STRING;
 #else
   std::string path_to_liblldb = "C:\\foo\\bar\\lib";
   std::string path_to_clang_dir = "C:\\foo\\bar\\lib\\clang\\" CLANG_VERSION_STRING;
diff --git a/llvm/CMakeLists.txt b/llvm/CMakeLists.txt
--- a/llvm/CMakeLists.txt
+++ b/llvm/CMakeLists.txt
@@ -55,6 +55,14 @@
   VERSION ${LLVM_VERSION_MAJOR}.${LLVM_VERSION_MINOR}.${LLVM_VERSION_PATCH}
   LANGUAGES C CXX ASM)
 
+if (NOT DEFINED CMAKE_INSTALL_LIBDIR AND DEFINED LLVM_LIBDIR_SUFFIX)
+  message(DEPRECATION
+    "\"LLVM_LIBDIR_SUFFIX\" is deprecated. "
+    "Please set \"CMAKE_INSTALL_LIBDIR\" directly instead.")
+  # Must go before `include(GNUInstallDirs)`.
+  set(CMAKE_INSTALL_LIBDIR "lib${LLVM_LIBDIR_SUFFIX}")
+endif()
+
 # Must go after project(..)
 include(GNUInstallDirs)
 
@@ -320,8 +328,6 @@
   message(FATAL_ERROR "Invalid value for CMAKE_BUILD_TYPE: ${CMAKE_BUILD_TYPE}")
 endif()
 
-set(LLVM_LIBDIR_SUFFIX "" CACHE STRING "Define suffix of library directory name (32/64)" )
-
 set(LLVM_TOOLS_INSTALL_DIR "${CMAKE_INSTALL_BINDIR}" CACHE STRING
     "Path for binary subdirectory (defaults to '${CMAKE_INSTALL_BINDIR}')")
 mark_as_advanced(LLVM_TOOLS_INSTALL_DIR)
@@ -336,7 +342,7 @@
 
 # They are used as destination of target generators.
 set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
+set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
 if(WIN32 OR CYGWIN)
   # DLL platform -- put DLLs into bin.
   set(LLVM_SHLIB_OUTPUT_INTDIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
@@ -883,8 +889,8 @@
 
 # They are not referenced. See set_output_directory().
 set( CMAKE_RUNTIME_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/bin )
-set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX} )
-set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX} )
+set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib )
+set( CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LLVM_BINARY_DIR}/lib )
 
 if(LLVM_INCLUDE_TESTS)
   include(GetErrcMessages)
@@ -942,7 +948,7 @@
   add_subdirectory(${TENSORFLOW_AOT_PATH}/xla_aot_runtime_src
     ${CMAKE_ARCHIVE_OUTPUT_DIRECTORY}/tf_runtime)
   install(TARGETS tf_xla_runtime EXPORT LLVMExports
-    ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT tf_xla_runtime)
+    ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}" COMPONENT tf_xla_runtime)
   set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS tf_xla_runtime)
   # Once we add more modules, we should handle this more automatically.
   if (DEFINED LLVM_OVERRIDE_MODEL_HEADER_INLINERSIZEMODEL)
diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -844,8 +844,8 @@
       get_target_export_arg(${name} LLVM export_to_llvmexports ${umbrella})
       install(TARGETS ${name}
               ${export_to_llvmexports}
-              LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT ${name}
-              ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX} COMPONENT ${name}
+              LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}" COMPONENT ${name}
+              ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}" COMPONENT ${name}
               RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}" COMPONENT ${name})
 
       if (NOT LLVM_ENABLE_IDE)
@@ -1093,7 +1093,7 @@
           message(FATAL_ERROR "LLVM_INSTALL_PACKAGE_DIR must be defined and writable. GEN_CONFIG should only be passe when building LLVM proper.")
       endif()
       # LLVM_INSTALL_PACKAGE_DIR might be absolute, so don't reuse below.
-      set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
+      set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
       file(WRITE
           "${llvm_cmake_builddir}/LLVMConfigExtensions.cmake"
           "set(LLVM_STATIC_EXTENSIONS ${LLVM_STATIC_EXTENSIONS})")
@@ -2007,7 +2007,7 @@
   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${LLVM_LIBDIR_SUFFIX})
+  set(output_dir "${CMAKE_INSTALL_FULL_LIBDIR}")
   if(WIN32 AND "${type}" STREQUAL "SHARED")
     set(output_dir "${CMAKE_INSTALL_BINDIR}")
   endif()
@@ -2271,15 +2271,15 @@
 
   if (APPLE)
     set(_install_name_dir INSTALL_NAME_DIR "@rpath")
-    set(_install_rpath "@loader_path/../lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
+    set(_install_rpath "@loader_path/../${CMAKE_INSTALL_LIBDIR}" ${extra_libdir})
   elseif(${CMAKE_SYSTEM_NAME} MATCHES "AIX" AND BUILD_SHARED_LIBS)
     # $ORIGIN is not interpreted at link time by aix ld.
     # Since BUILD_SHARED_LIBS is only recommended for use by developers,
     # hardcode the rpath to build/install lib dir first in this mode.
     # FIXME: update this when there is better solution.
-    set(_install_rpath "${LLVM_LIBRARY_OUTPUT_INTDIR}" "${CMAKE_INSTALL_PREFIX}/lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
+    set(_install_rpath "${LLVM_LIBRARY_OUTPUT_INTDIR}" "${CMAKE_INSTALL_FULL_LIBDIR}" ${extra_libdir})
   elseif(UNIX)
-    set(_install_rpath "\$ORIGIN/../lib${LLVM_LIBDIR_SUFFIX}" ${extra_libdir})
+    set(_install_rpath "\$ORIGIN/../${CMAKE_INSTALL_LIBDIR}" ${extra_libdir})
     if(${CMAKE_SYSTEM_NAME} MATCHES "(FreeBSD|DragonFly)")
       set_property(TARGET ${name} APPEND_STRING PROPERTY
                    LINK_FLAGS " -Wl,-z,origin ")
diff --git a/llvm/cmake/modules/AddOCaml.cmake b/llvm/cmake/modules/AddOCaml.cmake
--- a/llvm/cmake/modules/AddOCaml.cmake
+++ b/llvm/cmake/modules/AddOCaml.cmake
@@ -147,9 +147,9 @@
   endforeach()
 
   if( APPLE )
-    set(ocaml_rpath "@executable_path/../../../lib${LLVM_LIBDIR_SUFFIX}")
+    set(ocaml_rpath "@executable_path/../../../${CMAKE_INSTALL_LIBDIR}")
   elseif( UNIX )
-    set(ocaml_rpath "\\$ORIGIN/../../../lib${LLVM_LIBDIR_SUFFIX}")
+    set(ocaml_rpath "\\$ORIGIN/../../../${CMAKE_INSTALL_LIBDIR}")
   endif()
   list(APPEND ocaml_flags "-ldopt" "-Wl,-rpath,${ocaml_rpath}")
 
diff --git a/llvm/cmake/modules/CMakeLists.txt b/llvm/cmake/modules/CMakeLists.txt
--- a/llvm/cmake/modules/CMakeLists.txt
+++ b/llvm/cmake/modules/CMakeLists.txt
@@ -6,7 +6,7 @@
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
   "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
 
 # First for users who use an installed LLVM, create the LLVMExports.cmake file.
 set(LLVM_EXPORTS_FILE ${llvm_cmake_builddir}/LLVMExports.cmake)
@@ -128,7 +128,7 @@
   )
 list(REMOVE_DUPLICATES LLVM_CONFIG_INCLUDE_DIRS)
 
-extend_path(LLVM_CONFIG_LIBRARY_DIR "\${LLVM_INSTALL_PREFIX}" "lib\${LLVM_LIBDIR_SUFFIX}")
+extend_path(LLVM_CONFIG_LIBRARY_DIR "\${LLVM_INSTALL_PREFIX}" "${CMAKE_INSTALL_LIBDIR}")
 set(LLVM_CONFIG_LIBRARY_DIRS
   "${LLVM_CONFIG_LIBRARY_DIR}"
   # FIXME: Should there be other entries here?
diff --git a/llvm/cmake/modules/LLVMConfig.cmake.in b/llvm/cmake/modules/LLVMConfig.cmake.in
--- a/llvm/cmake/modules/LLVMConfig.cmake.in
+++ b/llvm/cmake/modules/LLVMConfig.cmake.in
@@ -104,8 +104,6 @@
 
 set(LLVM_ON_UNIX @LLVM_ON_UNIX@)
 
-set(LLVM_LIBDIR_SUFFIX @LLVM_LIBDIR_SUFFIX@)
-
 set(LLVM_INCLUDE_DIRS "@LLVM_CONFIG_INCLUDE_DIRS@")
 set(LLVM_LIBRARY_DIRS "@LLVM_CONFIG_LIBRARY_DIRS@")
 
@@ -120,6 +118,14 @@
 set(LLVM_MAIN_INCLUDE_DIR "@LLVM_CONFIG_MAIN_INCLUDE_DIR@")
 set(LLVM_LIBRARY_DIR "@LLVM_CONFIG_LIBRARY_DIR@")
 
+# Backwards compatibility for anything using the deprecated `LLVM_LIBDIR_SUFFIX`
+# downstream.
+if("{LLVM_LIBRARY_DIR}" MATCHES "lib([^/]*)$")
+  set(LLVM_LIBDIR_SUFFIX "${CMAKE_MATCH_0}")
+else()
+  set(LLVM_LIBDIR_SUFFIX "")
+endif()
+
 # This is a secondary one for generated files
 set(LLVM_INCLUDE_DIR "@LLVM_CONFIG_INCLUDE_DIR@")
 
diff --git a/llvm/docs/CMake.rst b/llvm/docs/CMake.rst
--- a/llvm/docs/CMake.rst
+++ b/llvm/docs/CMake.rst
@@ -247,11 +247,6 @@
   Control which runtimes are enabled. For example you may want to work on
   libc++ or libc++abi by specifying ``-DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi"``.
 
-**LLVM_LIBDIR_SUFFIX**:STRING
-  Extra suffix to append to the directory where libraries are to be
-  installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64``
-  to install libraries to ``/usr/lib64``.
-
 **LLVM_PARALLEL_{COMPILE,LINK}_JOBS**:STRING
   Building the llvm toolchain can use a lot of resources, particularly
   linking. These options, when you use the Ninja generator, allow you
@@ -284,6 +279,10 @@
   The path to install executables, relative to the *CMAKE_INSTALL_PREFIX*.
   Defaults to "bin".
 
+**CMAKE_INSTALL_LIBDIR**:PATH
+  The path to install libraries, relative to the *CMAKE_INSTALL_PREFIX*.
+  Defaults to "lib".
+
 **CMAKE_INSTALL_INCLUDEDIR**:PATH
   The path to install header files, relative to the *CMAKE_INSTALL_PREFIX*.
   Defaults to "include".
@@ -831,6 +830,21 @@
   Only matters if *LLVM_BUILD_EXAMPLES* is enabled.
   Defaults to "examples".
 
+Deprecated variables
+~~~~~~~~~~~~~~~~~~~~
+
+These will go away soon. Please try to avoid using them.
+
+**LLVM_LIBDIR_SUFFIX**:STRING
+
+  **Deprecated**: Use ``LLVM_LIBRARY_DIR`` or ``CMAKE_INSTALL_LIBDIR`` instead.
+  Only defined downstream for legacy consumers, not during the build of LLVM
+  itself.
+
+  Extra suffix to append to the directory where libraries are to be
+  installed. On a 64-bit architecture, one could use ``-DLLVM_LIBDIR_SUFFIX=64``
+  to install libraries to ``/usr/lib64``. See also ``CMAKE_INSTALL_LIBDIR``.
+
 CMake Caches
 ============
 
diff --git a/llvm/tools/llvm-config/BuildVariables.inc.in b/llvm/tools/llvm-config/BuildVariables.inc.in
--- a/llvm/tools/llvm-config/BuildVariables.inc.in
+++ b/llvm/tools/llvm-config/BuildVariables.inc.in
@@ -22,7 +22,7 @@
 #define LLVM_LDFLAGS "@LLVM_LDFLAGS@"
 #define LLVM_CXXFLAGS "@LLVM_CXXFLAGS@"
 #define LLVM_BUILDMODE "@LLVM_BUILDMODE@"
-#define LLVM_LIBDIR_SUFFIX "@LLVM_LIBDIR_SUFFIX@"
+#define LLVM_INSTALL_LIBDIR "@CMAKE_INSTALL_LIBDIR@"
 #define LLVM_INSTALL_INCLUDEDIR "@CMAKE_INSTALL_INCLUDEDIR@"
 #define LLVM_INSTALL_PACKAGE_DIR "@LLVM_INSTALL_PACKAGE_DIR@"
 #define LLVM_TARGETS_BUILT "@LLVM_TARGETS_BUILT@"
diff --git a/llvm/tools/llvm-config/llvm-config.cpp b/llvm/tools/llvm-config/llvm-config.cpp
--- a/llvm/tools/llvm-config/llvm-config.cpp
+++ b/llvm/tools/llvm-config/llvm-config.cpp
@@ -339,18 +339,16 @@
     switch (DevelopmentTreeLayout) {
     case CMakeStyle:
       ActiveBinDir = ActiveObjRoot + "/bin";
-      ActiveLibDir = ActiveObjRoot + "/lib" + LLVM_LIBDIR_SUFFIX;
+      ActiveLibDir = ActiveObjRoot + "/lib";
       ActiveCMakeDir = ActiveLibDir + "/cmake/llvm";
       break;
     case CMakeBuildModeStyle:
       // FIXME: Should we consider the build-mode-specific path as the prefix?
       ActivePrefix = ActiveObjRoot;
       ActiveBinDir = ActiveObjRoot + "/" + build_mode + "/bin";
-      ActiveLibDir =
-          ActiveObjRoot + "/" + build_mode + "/lib" + LLVM_LIBDIR_SUFFIX;
+      ActiveLibDir = ActiveObjRoot + "/" + build_mode + "/lib";
       // The CMake directory isn't separated by build mode.
-      ActiveCMakeDir =
-          ActivePrefix + "/lib" + LLVM_LIBDIR_SUFFIX + "/cmake/llvm";
+      ActiveCMakeDir = ActivePrefix + "/lib/cmake/llvm";
       break;
     }
 
@@ -369,7 +367,11 @@
       sys::fs::make_absolute(ActivePrefix, Path);
       ActiveBinDir = std::string(Path.str());
     }
-    ActiveLibDir = ActivePrefix + "/lib" + LLVM_LIBDIR_SUFFIX;
+    {
+      SmallString<256> Path(LLVM_INSTALL_LIBDIR);
+      sys::fs::make_absolute(ActivePrefix, Path);
+      ActiveLibDir = std::string(Path.str());
+    }
     {
       SmallString<256> Path(LLVM_INSTALL_PACKAGE_DIR);
       sys::fs::make_absolute(ActivePrefix, Path);
diff --git a/llvm/tools/llvm-shlib/CMakeLists.txt b/llvm/tools/llvm-shlib/CMakeLists.txt
--- a/llvm/tools/llvm-shlib/CMakeLists.txt
+++ b/llvm/tools/llvm-shlib/CMakeLists.txt
@@ -88,7 +88,7 @@
 
   set(LLVM_EXPORTED_SYMBOL_FILE ${LLVM_BINARY_DIR}/libllvm-c.exports)
 
-  set(LIB_DIR ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
+  set(LIB_DIR ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
   set(LIB_NAME ${LIB_DIR}/${CMAKE_SHARED_LIBRARY_PREFIX}LLVM)
   set(LIB_PATH ${LIB_NAME}${CMAKE_SHARED_LIBRARY_SUFFIX})
   set(LIB_EXPORTS_PATH ${LIB_NAME}.exports)
diff --git a/llvm/utils/gn/secondary/clang/include/clang/Config/BUILD.gn b/llvm/utils/gn/secondary/clang/include/clang/Config/BUILD.gn
--- a/llvm/utils/gn/secondary/clang/include/clang/Config/BUILD.gn
+++ b/llvm/utils/gn/secondary/clang/include/clang/Config/BUILD.gn
@@ -19,7 +19,6 @@
     "CLANG_DEFAULT_OPENMP_RUNTIME=libomp",
     "CLANG_DEFAULT_UNWINDLIB=",
     "CLANG_OPENMP_NVPTX_DEFAULT_ARCH=sm_35",
-    "CLANG_LIBDIR_SUFFIX=",
     "CLANG_RESOURCE_DIR=",
     "C_INCLUDE_DIRS=",
     "CLANG_CONFIG_FILE_SYSTEM_DIR=",
diff --git a/llvm/utils/gn/secondary/lldb/include/lldb/Host/BUILD.gn b/llvm/utils/gn/secondary/lldb/include/lldb/Host/BUILD.gn
--- a/llvm/utils/gn/secondary/lldb/include/lldb/Host/BUILD.gn
+++ b/llvm/utils/gn/secondary/lldb/include/lldb/Host/BUILD.gn
@@ -26,8 +26,6 @@
 
     "LLDB_PYTHON_HOME=",
 
-    "LLVM_LIBDIR_SUFFIX=",
-
     "HAVE_LIBCOMPRESSION=",
   ]
 
diff --git a/llvm/utils/gn/secondary/llvm/tools/llvm-config/BUILD.gn b/llvm/utils/gn/secondary/llvm/tools/llvm-config/BUILD.gn
--- a/llvm/utils/gn/secondary/llvm/tools/llvm-config/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/tools/llvm-config/BUILD.gn
@@ -71,6 +71,7 @@
   }
 
   values = [
+    "CMAKE_INSTALL_LIBDIR=lib",
     "CMAKE_INSTALL_INCLUDEDIR=include",
     "LLVM_SRC_ROOT=" + rebase_path("//llvm"),
     "LLVM_OBJ_ROOT=" + rebase_path(root_out_dir),
@@ -81,7 +82,6 @@
     "LLVM_LDFLAGS=.",  # FIXME
     "LLVM_CXXFLAGS=.",  # FIXME
     "LLVM_BUILDMODE=$build_mode",
-    "LLVM_LIBDIR_SUFFIX=",
     "LLVM_TARGETS_BUILT=$llvm_targets_to_build_string",
     "LLVM_SYSTEM_LIBS=$system_libs",
     "LLVM_BUILD_SYSTEM=gn",
diff --git a/mlir/CMakeLists.txt b/mlir/CMakeLists.txt
--- a/mlir/CMakeLists.txt
+++ b/mlir/CMakeLists.txt
@@ -28,7 +28,7 @@
   endif()
 
   set(CMAKE_LIBRARY_OUTPUT_DIRECTORY
-    "${CMAKE_CURRENT_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}")
+    "${CMAKE_CURRENT_BINARY_DIR}/lib")
   set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/bin")
 endif()
 
diff --git a/mlir/cmake/modules/AddMLIR.cmake b/mlir/cmake/modules/AddMLIR.cmake
--- a/mlir/cmake/modules/AddMLIR.cmake
+++ b/mlir/cmake/modules/AddMLIR.cmake
@@ -522,13 +522,13 @@
   install(TARGETS ${name}
     COMPONENT ${name}
     ${export_to_mlirtargets}
-    LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
-    ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+    LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+    ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
     RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
     # Note that CMake will create a directory like:
     #   objects-${CMAKE_BUILD_TYPE}/obj.LibName
     # and put object files there.
-    OBJECTS DESTINATION lib${LLVM_LIBDIR_SUFFIX}
+    OBJECTS DESTINATION "${CMAKE_INSTALL_LIBDIR}"
   )
 
   if (NOT LLVM_ENABLE_IDE)
diff --git a/mlir/cmake/modules/AddMLIRPython.cmake b/mlir/cmake/modules/AddMLIRPython.cmake
--- a/mlir/cmake/modules/AddMLIRPython.cmake
+++ b/mlir/cmake/modules/AddMLIRPython.cmake
@@ -408,8 +408,12 @@
     get_filename_component(_real_lib_dir "${LLVM_LIBRARY_OUTPUT_INTDIR}" REALPATH)
     set_property(TARGET ${target} APPEND PROPERTY
       BUILD_RPATH "${_real_lib_dir}")
-    set_property(TARGET ${target} APPEND PROPERTY
-      INSTALL_RPATH "${_origin_prefix}/${ARG_RELATIVE_INSTALL_ROOT}/lib${LLVM_LIBDIR_SUFFIX}")
+    if(NOT IS_ABSOLUTE "${CMAKE_INSTALL_LIBDIR}")
+      set(install_rpath "${_origin_prefix}/${ARG_RELATIVE_INSTALL_ROOT}/${CMAKE_INSTALL_LIBDIR}")
+	else()
+	  set(install_rpath "${CMAKE_INSTALL_LIBDIR}")
+	endif()
+    set_property(TARGET ${target} APPEND PROPERTY INSTALL_RPATH "${install_rpath}")
   endif()
 endfunction()
 
diff --git a/mlir/cmake/modules/CMakeLists.txt b/mlir/cmake/modules/CMakeLists.txt
--- a/mlir/cmake/modules/CMakeLists.txt
+++ b/mlir/cmake/modules/CMakeLists.txt
@@ -9,13 +9,13 @@
 set(MLIR_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/mlir" CACHE STRING
   "Path for CMake subdirectory for Polly (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/polly')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(mlir_cmake_builddir "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/mlir")
+set(mlir_cmake_builddir "${CMAKE_BINARY_DIR}/lib/cmake/mlir")
 
 # Keep this in sync with llvm/cmake/CMakeLists.txt!
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
   "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
 
 get_property(MLIR_EXPORTS GLOBAL PROPERTY MLIR_EXPORTS)
 export(TARGETS ${MLIR_EXPORTS} FILE ${mlir_cmake_builddir}/MLIRTargets.cmake)
diff --git a/mlir/test/CMakeLists.txt b/mlir/test/CMakeLists.txt
--- a/mlir/test/CMakeLists.txt
+++ b/mlir/test/CMakeLists.txt
@@ -8,7 +8,7 @@
 # Passed to lit.site.cfg.py.so that the out of tree Standalone dialect test
 # can find MLIR's CMake configuration
 set(MLIR_CMAKE_DIR
-  "${CMAKE_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/mlir")
+  "${CMAKE_BINARY_DIR}/lib/cmake/mlir")
 
 # Passed to lit.site.cfg.py.in to set up the path where to find the libraries
 # for linalg integration tests.
diff --git a/openmp/CMakeLists.txt b/openmp/CMakeLists.txt
--- a/openmp/CMakeLists.txt
+++ b/openmp/CMakeLists.txt
@@ -17,6 +17,9 @@
 # Must go below project(..)
 include(GNUInstallDirs)
 
+set(OPENMP_INSTALL_LIBDIR "${CMAKE_INSTALL_LIBDIR}" CACHE STRING
+  "lib installation directory, e.g. lib or lib64")
+
 if (OPENMP_STANDALONE_BUILD)
   # CMAKE_BUILD_TYPE was not set, default to Release.
   if (NOT CMAKE_BUILD_TYPE)
@@ -26,10 +29,6 @@
   # Group common settings.
   set(OPENMP_ENABLE_WERROR FALSE CACHE BOOL
     "Enable -Werror flags to turn warnings into errors for supporting compilers.")
-  set(OPENMP_LIBDIR_SUFFIX "" CACHE STRING
-    "Suffix of lib installation directory, e.g. 64 => lib64")
-  # Do not use OPENMP_LIBDIR_SUFFIX directly, use OPENMP_INSTALL_LIBDIR.
-  set(OPENMP_INSTALL_LIBDIR "lib${OPENMP_LIBDIR_SUFFIX}")
 
   # Group test settings.
   set(OPENMP_TEST_C_COMPILER ${CMAKE_C_COMPILER} CACHE STRING
@@ -39,8 +38,6 @@
   set(OPENMP_LLVM_TOOLS_DIR "" CACHE PATH "Path to LLVM tools for testing.")
 else()
   set(OPENMP_ENABLE_WERROR ${LLVM_ENABLE_WERROR})
-  # If building in tree, we honor the same install suffix LLVM uses.
-  set(OPENMP_INSTALL_LIBDIR "lib${LLVM_LIBDIR_SUFFIX}")
 
   if (NOT MSVC)
     set(OPENMP_TEST_C_COMPILER ${LLVM_RUNTIME_OUTPUT_INTDIR}/clang)
diff --git a/openmp/README.rst b/openmp/README.rst
--- a/openmp/README.rst
+++ b/openmp/README.rst
@@ -108,8 +108,8 @@
 **OPENMP_ENABLE_WERROR** = ``OFF|ON``
   Treat warnings as errors and fail, if a compiler warning is triggered.
 
-**OPENMP_LIBDIR_SUFFIX** = ``""``
-  Extra suffix to append to the directory where libraries are to be installed.
+**OPENMP_INSTALL_LIBDIR** = ``lib``
+  Name or path of the directory where libraries are to be installed.
 
 **OPENMP_TEST_C_COMPILER** = ``${CMAKE_C_COMPILER}``
   Compiler to use for testing. Defaults to the compiler that was also used for
diff --git a/polly/cmake/CMakeLists.txt b/polly/cmake/CMakeLists.txt
--- a/polly/cmake/CMakeLists.txt
+++ b/polly/cmake/CMakeLists.txt
@@ -7,12 +7,12 @@
 set(POLLY_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/polly" CACHE STRING
   "Path for CMake subdirectory for Polly (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/polly')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(polly_cmake_builddir "${POLLY_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/polly")
+set(polly_cmake_builddir "${POLLY_BINARY_DIR}/lib/cmake/polly")
 
 set(LLVM_INSTALL_PACKAGE_DIR "${CMAKE_INSTALL_PACKAGEDIR}/llvm" CACHE STRING
   "Path for CMake subdirectory for LLVM (defaults to '${CMAKE_INSTALL_PACKAGEDIR}/llvm')")
 # CMAKE_INSTALL_PACKAGEDIR might be absolute, so don't reuse below.
-set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}/cmake/llvm")
+set(llvm_cmake_builddir "${LLVM_BINARY_DIR}/lib/cmake/llvm")
 
 if (CMAKE_CONFIGURATION_TYPES)
   set(POLLY_EXPORTS_FILE_NAME "PollyExports-$<LOWER_CASE:$<CONFIG>>.cmake")
@@ -93,7 +93,7 @@
 find_prefix_from_config(POLLY_CONFIG_CODE POLLY_INSTALL_PREFIX "${POLLY_INSTALL_PACKAGE_DIR}")
 extend_path(POLLY_CONFIG_LLVM_CMAKE_DIR "\${POLLY_INSTALL_PREFIX}" "${LLVM_INSTALL_PACKAGE_DIR}")
 extend_path(POLLY_CONFIG_CMAKE_DIR "\${POLLY_INSTALL_PREFIX}" "${POLLY_INSTALL_PACKAGE_DIR}")
-extend_path(POLLY_CONFIG_LIBRARY_DIRS "\${POLLY_INSTALL_PREFIX}" "lib${LLVM_LIBDIR_SUFFIX}")
+extend_path(POLLY_CONFIG_LIBRARY_DIRS "\${POLLY_INSTALL_PREFIX}" "${CMAKE_INSTALL_LIBDIR}")
 extend_path(base_includedir "\${POLLY_INSTALL_PREFIX}" "${CMAKE_INSTALL_INCLUDEDIR}")
 if (POLLY_BUNDLED_ISL)
   set(POLLY_CONFIG_INCLUDE_DIRS
diff --git a/polly/cmake/polly_macros.cmake b/polly/cmake/polly_macros.cmake
--- a/polly/cmake/polly_macros.cmake
+++ b/polly/cmake/polly_macros.cmake
@@ -44,8 +44,8 @@
   if (NOT LLVM_INSTALL_TOOLCHAIN_ONLY OR ${name} STREQUAL "LLVMPolly")
     install(TARGETS ${name}
       EXPORT LLVMExports
-      LIBRARY DESTINATION lib${LLVM_LIBDIR_SUFFIX}
-      ARCHIVE DESTINATION lib${LLVM_LIBDIR_SUFFIX})
+      LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+      ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}")
   endif()
   set_property(GLOBAL APPEND PROPERTY LLVM_EXPORTS ${name})
 endmacro(add_polly_library)
diff --git a/polly/test/CMakeLists.txt b/polly/test/CMakeLists.txt
--- a/polly/test/CMakeLists.txt
+++ b/polly/test/CMakeLists.txt
@@ -46,7 +46,7 @@
 
 set(LLVM_BINARY_DIR "${LLVM_BINARY_DIR}")
 set(LLVM_TOOLS_DIR "${LLVM_TOOLS_BINARY_DIR}")
-set(LLVM_LIBS_DIR "${LLVM_BINARY_DIR}/lib${LLVM_LIBDIR_SUFFIX}")
+set(LLVM_LIBS_DIR "${LLVM_BINARY_DIR}/lib")
 if (CMAKE_LIBRARY_OUTPUT_DIRECTORY)
   set(POLLY_LIB_DIR ${CMAKE_LIBRARY_OUTPUT_DIRECTORY})
 else()
diff --git a/pstl/CMakeLists.txt b/pstl/CMakeLists.txt
--- a/pstl/CMakeLists.txt
+++ b/pstl/CMakeLists.txt
@@ -88,10 +88,10 @@
 install(EXPORT ParallelSTLTargets
         FILE ParallelSTLTargets.cmake
         NAMESPACE pstl::
-        DESTINATION lib/cmake/ParallelSTL)
+        DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/ParallelSTL")
 install(FILES "${CMAKE_CURRENT_BINARY_DIR}/ParallelSTLConfig.cmake"
               "${CMAKE_CURRENT_BINARY_DIR}/ParallelSTLConfigVersion.cmake"
-        DESTINATION lib/cmake/ParallelSTL)
+        DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/ParallelSTL")
 install(DIRECTORY include/
         DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
         PATTERN "*.in" EXCLUDE)
diff --git a/third-party/benchmark/src/CMakeLists.txt b/third-party/benchmark/src/CMakeLists.txt
--- a/third-party/benchmark/src/CMakeLists.txt
+++ b/third-party/benchmark/src/CMakeLists.txt
@@ -79,7 +79,7 @@
 configure_package_config_file (
   ${PROJECT_SOURCE_DIR}/cmake/Config.cmake.in
   ${project_config}
-  INSTALL_DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}
+  INSTALL_DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}"
   NO_SET_AND_CHECK_MACRO
   NO_CHECK_REQUIRED_COMPONENTS_MACRO
 )
@@ -100,8 +100,8 @@
   install(
     TARGETS ${targets_to_export}
     EXPORT ${targets_export_name}
-    ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
-    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+    ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+    LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
     RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
     INCLUDES DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
 
diff --git a/utils/bazel/llvm-project-overlay/clang/include/clang/Config/config.h b/utils/bazel/llvm-project-overlay/clang/include/clang/Config/config.h
--- a/utils/bazel/llvm-project-overlay/clang/include/clang/Config/config.h
+++ b/utils/bazel/llvm-project-overlay/clang/include/clang/Config/config.h
@@ -68,7 +68,7 @@
 #define CLANG_SYSTEMZ_DEFAULT_ARCH "z10"
 
 /* Multilib suffix for libdir. */
-#define CLANG_LIBDIR_SUFFIX ""
+#define CLANG_INSTALL_LIBDIR_BASENAME "lib"
 
 /* Relative directory for resource files */
 #define CLANG_RESOURCE_DIR ""