Support `make clang-test' when Clang is compiled outside of LLVM.

This may not work on build platforms that place the binaries on
special folders ($build_dir/bin/Release/) such as the VS IDE and
XCode. For fixing this it is necessary to add a lit.py configuration
option for saying where the Clang binaries are, and apply to that path
the same magit that is used with the path to the LLVM tools binary
directory. Doing this requires a bit of autoconf work.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@124969 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index b32c82e..c4237eb 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -47,7 +47,13 @@
 
 include(FindPythonInterp)
 if(PYTHONINTERP_FOUND)
-  set(CLANG_TEST_EXTRA_ARGS)
+  if( LLVM_MAIN_SRC_DIR )
+    set(LIT "${LLVM_SOURCE_DIR}/utils/lit/lit.py")
+  else()
+    set(LIT "${PATH_TO_LLVM_BUILD}/bin/llvm-lit")
+  endif()
+
+  set(CLANG_TEST_EXTRA_ARGS "--path=${CLANG_BINARY_DIR}/bin")
 
   option(CLANG_TEST_USE_VG "Run Clang tests under Valgrind" OFF)
   if(CLANG_TEST_USE_VG)
@@ -60,7 +66,7 @@
   foreach(testdir ${CLANG_TEST_DIRECTORIES})
     add_custom_target(clang-test-${testdir}
       COMMAND ${PYTHON_EXECUTABLE}
-                  ${LLVM_SOURCE_DIR}/utils/lit/lit.py
+                  ${LIT}
                   --param clang_site_config=${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg
                   --param build_config=${CMAKE_CFG_INTDIR}
                   ${LIT_ARGS}
@@ -71,7 +77,7 @@
 
   add_custom_target(clang-test
     COMMAND ${PYTHON_EXECUTABLE}
-                ${LLVM_SOURCE_DIR}/utils/lit/lit.py
+                ${LIT}
                 --param clang_site_config=${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg
                 --param build_config=${CMAKE_CFG_INTDIR}
                 ${LIT_ARGS}
@@ -80,7 +86,7 @@
 
   add_custom_target(clang-c++tests
     COMMAND ${PYTHON_EXECUTABLE}
-                ${LLVM_SOURCE_DIR}/utils/lit/lit.py
+                ${LIT}
                 --param clang_site_config=${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg
                 --param build_config=${CMAKE_CFG_INTDIR}
                 ${LIT_ARGS}
@@ -90,7 +96,7 @@
 
   add_custom_target(check-all
     COMMAND ${PYTHON_EXECUTABLE}
-                ${LLVM_SOURCE_DIR}/utils/lit/lit.py
+                ${LIT}
                 --param build_config=${CMAKE_CFG_INTDIR}
                 --param build_mode=${RUNTIME_BUILD_MODE}
                 ${LIT_ARGS}