--- a/utils/lit/README.txt	Wed Sep 14 00:12:37 2016 +0900
+++ b/utils/lit/README.txt	Fri Nov 17 20:32:31 2017 +0900
@@ -6,3 +6,36 @@
 summarizing their results, and providing indication of failures. lit is designed
 to be a lightweight testing tool with as simple a user interface as possible.
 
+=====================
+ Contributing to lit
+=====================
+
+Please browse the Test Suite > lit category in LLVM's Bugzilla for ideas on
+what to work on.
+
+Before submitting patches, run the test suite to ensure nothing has regressed:
+
+    # From within your LLVM source directory.
+    utils/lit/lit.py \
+        --path /path/to/your/llvm/build/bin \
+        utils/lit/tests
+
+Note that lit's tests depend on 'not' and 'FileCheck', LLVM utilities.
+You will need to have built LLVM tools in order to run lit's test suite
+successfully.
+
+You'll also want to confirm that lit continues to work when testing LLVM.
+Follow the instructions in http://llvm.org/docs/TestingGuide.html to run the
+regression test suite:
+
+    make check-llvm
+
+And be sure to run the llvm-lit wrapper script as well:
+
+    /path/to/your/llvm/build/bin/llvm-lit utils/lit/tests
+
+Finally, make sure lit works when installed via setuptools:
+
+    python utils/lit/setup.py install
+    lit --path /path/to/your/llvm/build/bin utils/lit/tests
+