Index: llvm/docs/LangRef.rst
===================================================================
--- llvm/docs/LangRef.rst
+++ llvm/docs/LangRef.rst
@@ -1601,18 +1601,25 @@
     transitively, call a memory-deallocation function (``free``, for example)
     on a memory allocation which existed before the call.
 
-    As a result, uncaptured pointers that are known to be dereferenceable
-    prior to a call to a function with the ``nofree`` attribute are still
-    known to be dereferenceable after the call. The capturing condition is
-    necessary in environments where the function might communicate the
-    pointer to another thread which then deallocates the memory.  Alternatively,
-    ``nosync`` would ensure such communication cannot happen and even captured
-    pointers cannot be freed by the function.
-
-    A ``nofree`` function is explicitly allowed to free memory which it
-    allocated or (if not ``nosync``) arrange for another thread to free
-    memory on it's behalf.  As a result, perhaps surprisingly, a ``nofree``
-    function can return a pointer to a previously deallocated memory object.
+    A ``nofree`` function is explicitly allowed to free memory which it (or a
+    transitive callee) allocated or (if not ``nosync``) arrange for another
+    thread to free memory on its behalf.
+
+    As a result, perhaps surprisingly, a ``nofree`` function can return a
+    pointer to a previously deallocated memory object.
+
+    As a result, any pointers passed to a call to a function with the ``nofree``
+    attribute which is all of
+    a) uncaptured prior to the call,
+    b) known not to be captured by the call (e.g. only passed to ``nocapture``
+       parameters), and
+    c) known to be dereferenceable prior to a call to a function with
+    are still known to be dereferenceable after the call.
+    The capturing conditions are necessary in environments where the
+    function might communicate the pointer to another thread which then
+    deallocates the memory.  Alternatively, ``nosync`` would ensure such
+    communication cannot happen in a well defined program and even captured
+    pointers cannot be freed or arranged to be freed by the function.
 ``noimplicitfloat``
     This attributes disables implicit floating-point instructions.
 ``noinline``