Index: llvm-toolchain-3.4-3.4.2/test/Makefile
===================================================================
--- llvm-toolchain-3.4-3.4.2.orig/test/Makefile
+++ llvm-toolchain-3.4-3.4.2/test/Makefile
@@ -29,6 +29,11 @@ else
 LIT_ARGS := -s -v
 endif
 
+# NJOBS allows an override of the number of threads
+ifneq ($(NJOBS),)
+LIT_ARGS += $(NJOBS)
+endif
+
 ifdef TESTSUITE
 LIT_TESTSUITE := $(TESTSUITE)
 else