gh-111354: simplify detection of RESUME after YIELD_VALUE at except-depth 1 (#111459)

2 files changed, 19 insertions, 2 deletions

diff --git a/Doc/library/dis.rst b/Doc/library/dis.rst
index 7c92360..1a5ca16 100644
--- a/Doc/library/dis.rst
+++ b/Doc/library/dis.rst
@@ -823,6 +823,8 @@ iterations of the loop.
    .. versionchanged:: 3.12
       oparg set to be the exception block depth, for efficient closing of generators.
 
+   .. versionchanged:: 3.13
+      this opcode no longer has an oparg
 
 .. opcode:: SETUP_ANNOTATIONS
 
@@ -1625,11 +1627,12 @@ iterations of the loop.
       success (``True``) or failure (``False``).
 
 
-.. opcode:: RESUME (where)
+.. opcode:: RESUME (context)
 
    A no-op. Performs internal tracing, debugging and optimization checks.
 
-   The ``where`` operand marks where the ``RESUME`` occurs:
+   The ``context`` oparand consists of two parts. The lowest two bits
+   indicate where the ``RESUME`` occurs:
 
    * ``0`` The start of a function, which is neither a generator, coroutine
      nor an async generator
@@ -1637,8 +1640,14 @@ iterations of the loop.
    * ``2`` After a ``yield from`` expression
    * ``3`` After an ``await`` expression
 
+   The next bit is ``1`` if the RESUME is at except-depth ``1``, and ``0``
+   otherwise.
+
    .. versionadded:: 3.11
 
+   .. versionchanged:: 3.13
+      The oparg value changed to include information about except-depth
+
 
 .. opcode:: RETURN_GENERATOR
 
diff --git a/Doc/whatsnew/3.13.rst b/Doc/whatsnew/3.13.rst
index e5f39c5..5ada880 100644
--- a/Doc/whatsnew/3.13.rst
+++ b/Doc/whatsnew/3.13.rst
@@ -945,6 +945,14 @@ Others
 
 * None yet
 
+CPython bytecode changes
+========================
+
+* ``YIELD_VALUE`` no longer has an oparg. The oparg of ``RESUME`` was
+  changed to add a bit indicating whether the except-depth is 1, which
+  is needed to optimize closing of generators.
+  (Contributed by Irit Katriel in :gh:`111354`.)
+
 Porting to Python 3.13
 ======================