gh-142250: Add hasjforward and hasjback collections to opcode.py and document in dis.rst

Author: khanak0509

Doc/library/dis.rst

@@ -813,18 +813,23 @@ not have to be) the original ``STACK[-2]``.
    .. versionadded:: 3.5
 
 
-.. opcode:: END_ASYNC_FOR
+.. opcode:: END_ASYNC_FOR (delta)
 
    Terminates an :keyword:`async for` loop.  Handles an exception raised
    when awaiting a next item. The stack contains the async iterable in
    ``STACK[-2]`` and the raised exception in ``STACK[-1]``. Both are popped.
    If the exception is not :exc:`StopAsyncIteration`, it is re-raised.
+   
+   Decrements the bytecode counter by *delta* to jump back to the loop start
+   if continuing iteration.
 
    .. versionadded:: 3.8
 
    .. versionchanged:: 3.11
       Exception representation on the stack now consist of one, not three, items.
 
+   .. versionchanged:: 3.14
+      Added the *delta* parameter. This opcode is now a backward jump instruction.
 
 .. opcode:: CLEANUP_THROW
 
@@ -2081,3 +2086,16 @@ instructions:
 
    .. deprecated:: 3.13
       All jumps are now relative. This list is empty.
+
+.. data:: hasjforward
+
+   Sequence of bytecodes that perform forward jumps.
+
+   .. versionadded:: 3.14
+
+.. data:: hasjback
+
+   Sequence of bytecodes that perform backward jumps, such as 
+   :opcode:`JUMP_BACKWARD`, :opcode:`FOR_ITER`, and :opcode:`END_ASYNC_FOR`.
+
+   .. versionadded:: 3.14

Lib/opcode.py

@@ -7,7 +7,7 @@
 
 __all__ = ["cmp_op", "stack_effect", "hascompare", "opname", "opmap",
            "HAVE_ARGUMENT", "EXTENDED_ARG", "hasarg", "hasconst", "hasname",
-           "hasjump", "hasjrel", "hasjabs", "hasfree", "haslocal", "hasexc"]
+           "hasjump", "hasjrel", "hasjabs", "hasjforward", "hasjback", "hasfree", "haslocal", "hasexc"]
 
 import builtins
 import _opcode
@@ -17,6 +17,18 @@
                               HAVE_ARGUMENT, MIN_INSTRUMENTED_OPCODE)  # noqa: F401
 EXTENDED_ARG = opmap['EXTENDED_ARG']
 
+def _is_backward_jump_op(op):
+    """Helper function to identify backward jump opcodes."""
+    # Get the opcode name from the op number
+    op_name = opname[op] if op < len(opname) else None
+    return op_name in (
+        'JUMP_BACKWARD',
+        'JUMP_BACKWARD_NO_INTERRUPT',
+        'FOR_ITER',
+        'END_ASYNC_FOR',
+    )
+
+
 opname = ['<%r>' % (op,) for op in range(max(opmap.values()) + 1)]
 for m in (opmap, _specialized_opmap):
     for op, i in m.items():
@@ -35,6 +47,12 @@
 haslocal = [op for op in opmap.values() if _opcode.has_local(op)]
 hasexc = [op for op in opmap.values() if _opcode.has_exc(op)]
 
+hasjforward = [op for op in hasjump if not _is_backward_jump_op(op)]
+hasjback = [op for op in hasjump if _is_backward_jump_op(op)]
+
+
+
+_intrinsic_1_descs = _opcode.get_intrinsic1_descs()
 
 _intrinsic_1_descs = _opcode.get_intrinsic1_descs()
 _intrinsic_2_descs = _opcode.get_intrinsic2_descs()