-* The bitcode format produced by a X.Y release will be readable by all following
- X.Z releases and the (X+1).0 release.
+* Additions and changes to the IR should be reflected in
+ ``test/Bitcode/compatibility.ll``.
+
+* The bitcode format produced by a X.Y release will be readable by all
+ following X.Z releases and the (X+1).0 release.
+
+* After each X.Y release, ``compatibility.ll`` must be copied to
+ ``compatibility-X.Y.ll``. The corresponding bitcode file should be assembled
+ using the X.Y build and committed as ``compatibility-X.Y.ll.bc``.