[lit] Add instructions to run lit's test suite

 - Patch by Brian Gesiak.

 - https://reviews.llvm.org/D24968

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282525 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/utils/lit/README.txt b/utils/lit/README.txt
index 8cf4840..3d294c8 100644 (file)
--- a/utils/lit/README.txt
+++ b/utils/lit/README.txt
@@ -6,3 +6,19 @@ lit is a portable tool for executing LLVM and Clang style test suites,
 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 read the TODO file in this directory 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.
+