Index: Bitcode/CMakeLists.txt
===================================================================
--- Bitcode/CMakeLists.txt
+++ Bitcode/CMakeLists.txt
@@ -1,7 +1,17 @@
-if(NOT TEST_SUITE_BENCHMARKING_ONLY)
-  llvm_add_subdirectories(Regression)
-  if(ARCH STREQUAL "x86")
-    llvm_add_subdirectories(simd_ops)
-  endif()
+# We need at least clang 3.9 to process the bitcode here.
+if(CMAKE_C_COMPILER_ID STREQUAL "Clang" AND
+    CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND
+    NOT CMAKE_C_COMPILER_VERSION VERSION_LESS "3.9" AND
+    NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS "3.9")
+  set(ENABLE_BITCODE_DEFAULT "True")
 endif()
 
+set(TEST_SUITE_ENABLE_BITCODE_TESTS ${ENABLE_BITCODE_DEFAULT} CACHE BOOL "Enable bitcode tests")
+if(TEST_SUITE_ENABLE_BITCODE_TESTS)
+  if(NOT TEST_SUITE_BENCHMARKING_ONLY)
+    llvm_add_subdirectories(Regression)
+    if(ARCH STREQUAL "x86")
+      llvm_add_subdirectories(simd_ops)
+    endif()
+  endif()
+endif()