Document new LOAD_METHOD instruction. Update docs for LOAD_ATTR

Author: markshannon

Doc/library/dis.rst

@@ -1215,21 +1215,28 @@ iterations of the loop.
 
 .. opcode:: LOAD_ATTR (namei)
 
-   If the low bit of ``namei`` is not set, this replaces ``STACK[-1]`` with
-   ``getattr(STACK[-1], co_names[namei>>1])``.
+   Replaces ``STACK[-1]`` with ``getattr(STACK[-1], co_names[namei>>1])``.
 
-   If the low bit of ``namei`` is set, this will attempt to load a method named
-   ``co_names[namei>>1]`` from the ``STACK[-1]`` object. ``STACK[-1]`` is popped.
+   .. versionchanged:: 3.12
+      If the low bit of ``namei`` is set, then a ``NULL`` or ``self`` is
+      pushed to the stack before the attribute or unbound method respectively.
+
+   .. versionchanged:: 3.14
+      Reverted change from 3.12. The low bit of ``namei`` has no special meaning.
+
+
+.. opcode:: LOAD_METHOD (namei)
+
+   Attempt to load a method named ``co_names[namei>>1]`` from the ``STACK[-1]`` object.
+   ``STACK[-1]`` is popped.
    This bytecode distinguishes two cases: if ``STACK[-1]`` has a method with the
    correct name, the bytecode pushes the unbound method and ``STACK[-1]``.
    ``STACK[-1]`` will be used as the first argument (``self``) by :opcode:`CALL`
    or :opcode:`CALL_KW` when calling the unbound method.
    Otherwise, ``NULL`` and the object returned by
    the attribute lookup are pushed.
 
-   .. versionchanged:: 3.12
-      If the low bit of ``namei`` is set, then a ``NULL`` or ``self`` is
-      pushed to the stack before the attribute or unbound method respectively.
+   .. versionadded:: 3.14
 
 
 .. opcode:: LOAD_SUPER_ATTR (namei)