Index: test/lit.common.cfg
===================================================================
--- test/lit.common.cfg
+++ test/lit.common.cfg
@@ -75,10 +75,19 @@
   if name in config.environment:
     del config.environment[name]
 
+path = config.environment['PATH']
+
 # Tweak PATH to include llvm tools dir.
 if (not config.llvm_tools_dir) or (not os.path.exists(config.llvm_tools_dir)):
   lit_config.fatal("Invalid llvm_tools_dir config attribute: %r" % config.llvm_tools_dir)
-path = os.path.pathsep.join((config.llvm_tools_dir, config.environment['PATH']))
+path = os.path.pathsep.join((config.llvm_tools_dir, path))
+
+# Tweak PATH to include lit tools dir if specified.
+if config.lit_tools_dir:
+  if not os.path.exists(config.lit_tools_dir):
+    lit_config.fatal("Invalid lit_tools_dir config attribute: %r" % config.lit_tools_dir)
+  path = os.path.pathsep.join((config.lit_tools_dir, path))
+
 config.environment['PATH'] = path
 
 # Help MSVS link.exe find the standard libraries.
Index: test/lit.common.configured.in
===================================================================
--- test/lit.common.configured.in
+++ test/lit.common.configured.in
@@ -18,6 +18,7 @@
 set_default("compiler_rt_obj_root", "@COMPILER_RT_BINARY_DIR@")
 set_default("llvm_tools_dir", "@LLVM_TOOLS_DIR@")
 set_default("llvm_shlib_dir", "@LLVM_LIBRARY_OUTPUT_INTDIR@")
+set_default("lit_tools_dir", "@LLVM_LIT_TOOLS_DIR@")
 set_default("gold_executable", "@GOLD_EXECUTABLE@")
 set_default("clang", "@COMPILER_RT_RESOLVED_TEST_COMPILER@")
 set_default("compiler_id", "@COMPILER_RT_TEST_COMPILER_ID@")