Skip to content
Snippets Groups Projects
Unverified Commit 22739a0e authored by C.A.M. Gerlach's avatar C.A.M. Gerlach Committed by GitHub
Browse files

gh-95913: Edit, expand & format Bytecode sect in 3.11 WhatsNew (GH-98559)

parent e81fad6b
Branches
Tags
No related merge requests found
Show whitespace changes
Inline Side-by-side
Showing
with 81 additions and 39 deletions
Doc/whatsnew/3.11.rst
+ 81
− 39
View file @ 22739a0e
...@@ -1481,58 +1481,100 @@ contributors are volunteers from the community. ...@@ -1481,58 +1481,100 @@ contributors are volunteers from the community.
CPython bytecode changes CPython bytecode changes
======================== ========================
* The bytecode now contains inline cache entries, which take the form of The bytecode now contains inline cache entries,
:opcode:`CACHE` instructions. Many opcodes expect to be followed by an exact which take the form of the newly-added :opcode:`CACHE` instructions.
number of caches, and instruct the interpreter to skip over them at runtime. Many opcodes expect to be followed by an exact number of caches,
Populated caches can look like arbitrary instructions, so great care should be and instruct the interpreter to skip over them at runtime.
taken when reading or modifying raw, adaptive bytecode containing quickened Populated caches can look like arbitrary instructions,
data. so great care should be taken when reading or modifying
raw, adaptive bytecode containing quickened data.
* Replaced all numeric ``BINARY_*`` and ``INPLACE_*`` instructions with a single
:opcode:`BINARY_OP` implementation.
* Replaced the three call instructions: :opcode:`CALL_FUNCTION`, .. _whatsnew311-added-opcodes:
:opcode:`CALL_FUNCTION_KW` and :opcode:`CALL_METHOD` with
:opcode:`PUSH_NULL`, :opcode:`PRECALL`, :opcode:`CALL`,
and :opcode:`KW_NAMES`.
This decouples the argument shifting for methods from the handling of
keyword arguments and allows better specialization of calls.
* Removed ``COPY_DICT_WITHOUT_KEYS`` and ``GEN_START``. New opcodes
-----------
* :opcode:`ASYNC_GEN_WRAP`, :opcode:`RETURN_GENERATOR` and :opcode:`SEND`,
used in generators and co-routines.
* :opcode:`MATCH_CLASS` and :opcode:`MATCH_KEYS` no longer push an additional * :opcode:`COPY_FREE_VARS`,
boolean value indicating whether the match succeeded or failed. Instead, they which avoids needing special caller-side code for closures.
indicate failure with :const:`None` (where a tuple of extracted values would
otherwise be).
* Replace several stack manipulation instructions (``DUP_TOP``, ``DUP_TOP_TWO``, * :opcode:`JUMP_BACKWARD_NO_INTERRUPT`,
``ROT_TWO``, ``ROT_THREE``, ``ROT_FOUR``, and ``ROT_N``) with new for use in certain loops where handling interrupts is undesirable.
:opcode:`COPY` and :opcode:`SWAP` instructions.
* Replaced :opcode:`JUMP_IF_NOT_EXC_MATCH` by :opcode:`CHECK_EXC_MATCH` which * :opcode:`MAKE_CELL`, to create :ref:`cell-objects`.
performs the check but does not jump.
* Replaced :opcode:`JUMP_IF_NOT_EG_MATCH` by :opcode:`CHECK_EG_MATCH` which * :opcode:`CHECK_EG_MATCH` and :opcode:`PREP_RERAISE_STAR`,
performs the check but does not jump. to handle the :ref:`new exception groups and except* <whatsnew311-pep654>`
added in :pep:`654`.
* Replaced :opcode:`JUMP_ABSOLUTE` by the relative :opcode:`JUMP_BACKWARD`. * :opcode:`PUSH_EXC_INFO`, for use in exception handlers.
* Added :opcode:`JUMP_BACKWARD_NO_INTERRUPT`, which is used in certain loops where it * :opcode:`RESUME`, a no-op,
is undesirable to handle interrupts. for internal tracing, debugging and optimization checks.
* Replaced :opcode:`POP_JUMP_IF_TRUE` and :opcode:`POP_JUMP_IF_FALSE` by
the relative :opcode:`POP_JUMP_FORWARD_IF_TRUE`, :opcode:`POP_JUMP_BACKWARD_IF_TRUE`,
:opcode:`POP_JUMP_FORWARD_IF_FALSE` and :opcode:`POP_JUMP_BACKWARD_IF_FALSE`.
* Added :opcode:`POP_JUMP_FORWARD_IF_NOT_NONE`, :opcode:`POP_JUMP_BACKWARD_IF_NOT_NONE`, .. _whatsnew311-replaced-opcodes:
:opcode:`POP_JUMP_FORWARD_IF_NONE` and :opcode:`POP_JUMP_BACKWARD_IF_NONE`
opcodes to speed up conditional jumps.
* :opcode:`JUMP_IF_TRUE_OR_POP` and :opcode:`JUMP_IF_FALSE_OR_POP` are now Replaced opcodes
relative rather than absolute. ----------------
* :opcode:`RESUME` has been added. It is a no-op. Performs internal tracing, +------------------------------------+-----------------------------------+-----------------------------------------+
debugging and optimization checks. | Replaced Opcode(s) | New Opcode(s) | Notes |
+====================================+===================================+=========================================+
| | :opcode:`!BINARY_*` | :opcode:`BINARY_OP` | Replaced all numeric binary/in-place |
| | :opcode:`!INPLACE_*` | | opcodes with a single opcode |
+------------------------------------+-----------------------------------+-----------------------------------------+
| | :opcode:`!CALL_FUNCTION` | | :opcode:`CALL` | Decouples argument shifting for methods |
| | :opcode:`!CALL_FUNCTION_KW` | | :opcode:`KW_NAMES` | from handling of keyword arguments; |
| | :opcode:`!CALL_METHOD` | | :opcode:`PRECALL` | allows better specialization of calls |
| | | :opcode:`PUSH_NULL` | |
+------------------------------------+-----------------------------------+-----------------------------------------+
| | :opcode:`!DUP_TOP` | | :opcode:`COPY` | Stack manipulation instructions |
| | :opcode:`!DUP_TOP_TWO` | | :opcode:`SWAP` | |
| | :opcode:`!ROT_TWO` | | |
| | :opcode:`!ROT_THREE` | | |
| | :opcode:`!ROT_FOUR` | | |
| | :opcode:`!ROT_N` | | |
+------------------------------------+-----------------------------------+-----------------------------------------+
| | :opcode:`!JUMP_IF_NOT_EXC_MATCH` | | :opcode:`CHECK_EXC_MATCH` | Now performs check but doesn't jump |
+------------------------------------+-----------------------------------+-----------------------------------------+
| | :opcode:`!JUMP_ABSOLUTE` | | :opcode:`JUMP_BACKWARD` | See [#bytecode-jump]_; |
| | :opcode:`!POP_JUMP_IF_FALSE` | | :opcode:`POP_JUMP_BACKWARD_IF_* | ``TRUE``, ``FALSE``, |
| | :opcode:`!POP_JUMP_IF_TRUE` | <POP_JUMP_BACKWARD_IF_TRUE>` | ``NONE`` and ``NOT_NONE`` variants |
| | | :opcode:`POP_JUMP_FORWARD_IF_* | for each direction |
| | <POP_JUMP_FORWARD_IF_TRUE>` | |
+------------------------------------+-----------------------------------+-----------------------------------------+
| | :opcode:`!SETUP_WITH` | :opcode:`BEFORE_WITH` | :keyword:`with` block setup |
| | :opcode:`!SETUP_ASYNC_WITH` | | |
+------------------------------------+-----------------------------------+-----------------------------------------+
.. [#bytecode-jump] All jump opcodes are now relative, including the
existing :opcode:`JUMP_IF_TRUE_OR_POP` and :opcode:`JUMP_IF_FALSE_OR_POP`.
The argument is now an offset from the current instruction
rather than an absolute location.
.. _whatsnew311-changed-opcodes:
.. _whatsnew311-removed-opcodes:
.. _whatsnew311-changed-removed-opcodes:
Changed/removed opcodes
-----------------------
* Changed :opcode:`MATCH_CLASS` and :opcode:`MATCH_KEYS`
to no longer push an additional boolean value to indicate success/failure.
Instead, ``None`` is pushed on failure
in place of the tuple of extracted values.
* Changed opcodes that work with exceptions to reflect them
now being represented as one item on the stack instead of three
(see :gh:`89874`).
* Removed :opcode:`!COPY_DICT_WITHOUT_KEYS`, :opcode:`!GEN_START`,
:opcode:`!POP_BLOCK`, :opcode:`!SETUP_FINALLY` and :opcode:`!YIELD_FROM`.
.. _whatsnew311-deprecated: .. _whatsnew311-deprecated:
......
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Please register or to comment