diff --git a/clang/test/Unit/lit.site.cfg.py.in b/clang/test/Unit/lit.site.cfg.py.in
index ad5e6d0..400a9c0 100644
--- a/clang/test/Unit/lit.site.cfg.py.in
+++ b/clang/test/Unit/lit.site.cfg.py.in
@@ -2,14 +2,14 @@
 
 import sys
 
-config.llvm_src_root = path(r"@LLVM_SOURCE_DIR@")
-config.llvm_obj_root = path(r"@LLVM_BINARY_DIR@")
-config.llvm_tools_dir = path(r"@LLVM_TOOLS_DIR@")
-config.llvm_libs_dir = path(r"@LLVM_LIBS_DIR@")
+config.llvm_src_root = path("@LLVM_SOURCE_DIR@")
+config.llvm_obj_root = path("@LLVM_BINARY_DIR@")
+config.llvm_tools_dir = path("@LLVM_TOOLS_DIR@")
+config.llvm_libs_dir = path("@LLVM_LIBS_DIR@")
 config.llvm_build_mode = "@LLVM_BUILD_MODE@"
-config.clang_obj_root = path(r"@CLANG_BINARY_DIR@")
+config.clang_obj_root = path("@CLANG_BINARY_DIR@")
 config.enable_shared = @ENABLE_SHARED@
-config.shlibdir = path(r"@SHLIBDIR@")
+config.shlibdir = path("@SHLIBDIR@")
 config.target_triple = "@TARGET_TRIPLE@"
 
 # Support substitution of the tools_dir, libs_dirs, and build_mode with user
@@ -26,4 +26,4 @@
 
 # Let the main config do the real work.
 lit_config.load_config(
-    config, os.path.join(path(r"@CLANG_SOURCE_DIR@"), "test/Unit/lit.cfg.py"))
+    config, os.path.join(path("@CLANG_SOURCE_DIR@"), "test/Unit/lit.cfg.py"))
diff --git a/clang/test/lit.site.cfg.py.in b/clang/test/lit.site.cfg.py.in
index daec694..84dd0f8 100644
--- a/clang/test/lit.site.cfg.py.in
+++ b/clang/test/lit.site.cfg.py.in
@@ -2,16 +2,16 @@
 
 import sys
 
-config.llvm_src_root = path(r"@LLVM_SOURCE_DIR@")
-config.llvm_obj_root = path(r"@LLVM_BINARY_DIR@")
-config.llvm_tools_dir = path(r"@LLVM_TOOLS_DIR@")
-config.llvm_libs_dir = path(r"@LLVM_LIBS_DIR@")
-config.llvm_shlib_dir = path(r"@SHLIBDIR@")
+config.llvm_src_root = path("@LLVM_SOURCE_DIR@")
+config.llvm_obj_root = path("@LLVM_BINARY_DIR@")
+config.llvm_tools_dir = path("@LLVM_TOOLS_DIR@")
+config.llvm_libs_dir = path("@LLVM_LIBS_DIR@")
+config.llvm_shlib_dir = path("@SHLIBDIR@")
 config.llvm_plugin_ext = "@LLVM_PLUGIN_EXT@"
-config.lit_tools_dir = path(r"@LLVM_LIT_TOOLS_DIR@")
-config.clang_obj_root = path(r"@CLANG_BINARY_DIR@")
-config.clang_src_dir = path(r"@CLANG_SOURCE_DIR@")
-config.clang_tools_dir = path(r"@CLANG_TOOLS_DIR@")
+config.lit_tools_dir = path("@LLVM_LIT_TOOLS_DIR@")
+config.clang_obj_root = path("@CLANG_BINARY_DIR@")
+config.clang_src_dir = path("@CLANG_SOURCE_DIR@")
+config.clang_tools_dir = path("@CLANG_TOOLS_DIR@")
 config.host_triple = "@LLVM_HOST_TRIPLE@"
 config.target_triple = "@TARGET_TRIPLE@"
 config.host_cxx = "@CMAKE_CXX_COMPILER@"
diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
index 0732ca6..a474071 100644
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -1486,7 +1486,7 @@
     string(REPLACE ";" "\\;" ARG_PATH_VALUES_ESCAPED "${ARG_PATH_VALUES}")
     get_filename_component(OUTPUT_DIR ${site_out} DIRECTORY)
     execute_process(COMMAND "${PYTHON_EXECUTABLE}" "-c"
-      "import os, sys; sys.stdout.write(';'.join(os.path.relpath(p, sys.argv[1]) if p else '' for p in sys.argv[2].split(';')))"
+      "import os, sys; sys.stdout.write(';'.join(os.path.relpath(p, sys.argv[1]).replace('\\\\', '/') if p else '' for p in sys.argv[2].split(';')))"
       ${OUTPUT_DIR}
       ${ARG_PATH_VALUES_ESCAPED}
       OUTPUT_VARIABLE ARG_PATH_VALUES_RELATIVE)
diff --git a/llvm/test/Unit/lit.site.cfg.py.in b/llvm/test/Unit/lit.site.cfg.py.in
index f9fe421..3358ccf 100644
--- a/llvm/test/Unit/lit.site.cfg.py.in
+++ b/llvm/test/Unit/lit.site.cfg.py.in
@@ -2,12 +2,12 @@
 
 import sys
 
-config.llvm_src_root = path(r"@LLVM_SOURCE_DIR@")
-config.llvm_obj_root = path(r"@LLVM_BINARY_DIR@")
-config.llvm_tools_dir = path(r"@LLVM_TOOLS_DIR@")
+config.llvm_src_root = path("@LLVM_SOURCE_DIR@")
+config.llvm_obj_root = path("@LLVM_BINARY_DIR@")
+config.llvm_tools_dir = path("@LLVM_TOOLS_DIR@")
 config.llvm_build_mode = "@LLVM_BUILD_MODE@"
 config.enable_shared = @ENABLE_SHARED@
-config.shlibdir = path(r"@SHLIBDIR@")
+config.shlibdir = path("@SHLIBDIR@")
 
 # Support substitution of the tools_dir and build_mode with user parameters.
 # This is used when we can't determine the tool dir at configuration time.
diff --git a/llvm/test/lit.site.cfg.py.in b/llvm/test/lit.site.cfg.py.in
index ee9e594..2af0ec3 100644
--- a/llvm/test/lit.site.cfg.py.in
+++ b/llvm/test/lit.site.cfg.py.in
@@ -4,14 +4,14 @@
 
 config.host_triple = "@LLVM_HOST_TRIPLE@"
 config.target_triple = "@TARGET_TRIPLE@"
-config.llvm_src_root = path(r"@LLVM_SOURCE_DIR@")
-config.llvm_obj_root = path(r"@LLVM_BINARY_DIR@")
-config.llvm_tools_dir = path(r"@LLVM_TOOLS_DIR@")
-config.llvm_lib_dir = path(r"@LLVM_LIBRARY_DIR@")
-config.llvm_shlib_dir = path(r"@SHLIBDIR@")
+config.llvm_src_root = path("@LLVM_SOURCE_DIR@")
+config.llvm_obj_root = path("@LLVM_BINARY_DIR@")
+config.llvm_tools_dir = path("@LLVM_TOOLS_DIR@")
+config.llvm_lib_dir = path("@LLVM_LIBRARY_DIR@")
+config.llvm_shlib_dir = path("@SHLIBDIR@")
 config.llvm_shlib_ext = "@SHLIBEXT@"
 config.llvm_exe_ext = "@EXEEXT@"
-config.lit_tools_dir = path(r"@LLVM_LIT_TOOLS_DIR@")
+config.lit_tools_dir = path("@LLVM_LIT_TOOLS_DIR@")
 config.python_executable = "@PYTHON_EXECUTABLE@"
 config.gold_executable = "@GOLD_EXECUTABLE@"
 config.ld64_executable = "@LD64_EXECUTABLE@"