mirror of https://github.com/python/cpython
1844 lines
54 KiB
ReStructuredText
1844 lines
54 KiB
ReStructuredText
:mod:`dis` --- Disassembler for Python bytecode
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===============================================
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.. module:: dis
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:synopsis: Disassembler for Python bytecode.
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**Source code:** :source:`Lib/dis.py`
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.. testsetup::
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import dis
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def myfunc(alist):
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return len(alist)
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--------------
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The :mod:`dis` module supports the analysis of CPython :term:`bytecode` by
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disassembling it. The CPython bytecode which this module takes as an input is
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defined in the file :file:`Include/opcode.h` and used by the compiler and the
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interpreter.
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.. impl-detail::
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Bytecode is an implementation detail of the CPython interpreter. No
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guarantees are made that bytecode will not be added, removed, or changed
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between versions of Python. Use of this module should not be considered to
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work across Python VMs or Python releases.
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.. versionchanged:: 3.6
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Use 2 bytes for each instruction. Previously the number of bytes varied
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by instruction.
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.. versionchanged:: 3.10
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The argument of jump, exception handling and loop instructions is now
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the instruction offset rather than the byte offset.
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.. versionchanged:: 3.11
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Some instructions are accompanied by one or more inline cache entries,
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which take the form of :opcode:`CACHE` instructions. These instructions
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are hidden by default, but can be shown by passing ``show_caches=True`` to
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any :mod:`dis` utility. Furthermore, the interpreter now adapts the
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bytecode to specialize it for different runtime conditions. The
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adaptive bytecode can be shown by passing ``adaptive=True``.
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Example: Given the function :func:`myfunc`::
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def myfunc(alist):
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return len(alist)
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the following command can be used to display the disassembly of
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:func:`myfunc`:
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.. doctest::
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>>> dis.dis(myfunc)
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2 0 RESUME 0
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<BLANKLINE>
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3 2 LOAD_GLOBAL 1 (NULL + len)
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12 LOAD_FAST 0 (alist)
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14 CALL 1
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22 RETURN_VALUE
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(The "2" is a line number).
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Bytecode analysis
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-----------------
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.. versionadded:: 3.4
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The bytecode analysis API allows pieces of Python code to be wrapped in a
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:class:`Bytecode` object that provides easy access to details of the compiled
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code.
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.. class:: Bytecode(x, *, first_line=None, current_offset=None,\
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show_caches=False, adaptive=False)
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Analyse the bytecode corresponding to a function, generator, asynchronous
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generator, coroutine, method, string of source code, or a code object (as
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returned by :func:`compile`).
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This is a convenience wrapper around many of the functions listed below, most
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notably :func:`get_instructions`, as iterating over a :class:`Bytecode`
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instance yields the bytecode operations as :class:`Instruction` instances.
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If *first_line* is not ``None``, it indicates the line number that should be
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reported for the first source line in the disassembled code. Otherwise, the
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source line information (if any) is taken directly from the disassembled code
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object.
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If *current_offset* is not ``None``, it refers to an instruction offset in the
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disassembled code. Setting this means :meth:`.dis` will display a "current
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instruction" marker against the specified opcode.
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If *show_caches* is ``True``, :meth:`.dis` will display inline cache
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entries used by the interpreter to specialize the bytecode.
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If *adaptive* is ``True``, :meth:`.dis` will display specialized bytecode
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that may be different from the original bytecode.
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.. classmethod:: from_traceback(tb, *, show_caches=False)
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Construct a :class:`Bytecode` instance from the given traceback, setting
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*current_offset* to the instruction responsible for the exception.
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.. data:: codeobj
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The compiled code object.
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.. data:: first_line
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The first source line of the code object (if available)
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.. method:: dis()
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Return a formatted view of the bytecode operations (the same as printed by
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:func:`dis.dis`, but returned as a multi-line string).
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.. method:: info()
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Return a formatted multi-line string with detailed information about the
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code object, like :func:`code_info`.
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.. versionchanged:: 3.7
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This can now handle coroutine and asynchronous generator objects.
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.. versionchanged:: 3.11
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Added the *show_caches* and *adaptive* parameters.
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Example:
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.. doctest::
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>>> bytecode = dis.Bytecode(myfunc)
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>>> for instr in bytecode:
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... print(instr.opname)
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...
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RESUME
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LOAD_GLOBAL
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LOAD_FAST
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CALL
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RETURN_VALUE
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Analysis functions
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------------------
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The :mod:`dis` module also defines the following analysis functions that convert
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the input directly to the desired output. They can be useful if only a single
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operation is being performed, so the intermediate analysis object isn't useful:
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.. function:: code_info(x)
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Return a formatted multi-line string with detailed code object information
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for the supplied function, generator, asynchronous generator, coroutine,
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method, source code string or code object.
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Note that the exact contents of code info strings are highly implementation
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dependent and they may change arbitrarily across Python VMs or Python
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releases.
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.. versionadded:: 3.2
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.. versionchanged:: 3.7
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This can now handle coroutine and asynchronous generator objects.
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.. function:: show_code(x, *, file=None)
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Print detailed code object information for the supplied function, method,
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source code string or code object to *file* (or ``sys.stdout`` if *file*
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is not specified).
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This is a convenient shorthand for ``print(code_info(x), file=file)``,
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intended for interactive exploration at the interpreter prompt.
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.. versionadded:: 3.2
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.. versionchanged:: 3.4
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Added *file* parameter.
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.. function:: dis(x=None, *, file=None, depth=None, show_caches=False, adaptive=False)
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Disassemble the *x* object. *x* can denote either a module, a class, a
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method, a function, a generator, an asynchronous generator, a coroutine,
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a code object, a string of source code or a byte sequence of raw bytecode.
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For a module, it disassembles all functions. For a class, it disassembles
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all methods (including class and static methods). For a code object or
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sequence of raw bytecode, it prints one line per bytecode instruction.
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It also recursively disassembles nested code objects. These can include
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generator expressions, nested functions, the bodies of nested classes,
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and the code objects used for :ref:`annotation scopes <annotation-scopes>`.
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Strings are first compiled to code objects with the :func:`compile`
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built-in function before being disassembled. If no object is provided, this
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function disassembles the last traceback.
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The disassembly is written as text to the supplied *file* argument if
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provided and to ``sys.stdout`` otherwise.
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The maximal depth of recursion is limited by *depth* unless it is ``None``.
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``depth=0`` means no recursion.
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If *show_caches* is ``True``, this function will display inline cache
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entries used by the interpreter to specialize the bytecode.
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If *adaptive* is ``True``, this function will display specialized bytecode
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that may be different from the original bytecode.
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.. versionchanged:: 3.4
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Added *file* parameter.
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.. versionchanged:: 3.7
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Implemented recursive disassembling and added *depth* parameter.
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.. versionchanged:: 3.7
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This can now handle coroutine and asynchronous generator objects.
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.. versionchanged:: 3.11
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Added the *show_caches* and *adaptive* parameters.
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.. function:: distb(tb=None, *, file=None, show_caches=False, adaptive=False)
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Disassemble the top-of-stack function of a traceback, using the last
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traceback if none was passed. The instruction causing the exception is
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indicated.
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The disassembly is written as text to the supplied *file* argument if
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provided and to ``sys.stdout`` otherwise.
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.. versionchanged:: 3.4
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Added *file* parameter.
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.. versionchanged:: 3.11
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Added the *show_caches* and *adaptive* parameters.
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.. function:: disassemble(code, lasti=-1, *, file=None, show_caches=False, adaptive=False)
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disco(code, lasti=-1, *, file=None, show_caches=False, adaptive=False)
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Disassemble a code object, indicating the last instruction if *lasti* was
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provided. The output is divided in the following columns:
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#. the line number, for the first instruction of each line
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#. the current instruction, indicated as ``-->``,
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#. a labelled instruction, indicated with ``>>``,
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#. the address of the instruction,
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#. the operation code name,
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#. operation parameters, and
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#. interpretation of the parameters in parentheses.
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The parameter interpretation recognizes local and global variable names,
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constant values, branch targets, and compare operators.
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The disassembly is written as text to the supplied *file* argument if
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provided and to ``sys.stdout`` otherwise.
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.. versionchanged:: 3.4
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Added *file* parameter.
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.. versionchanged:: 3.11
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Added the *show_caches* and *adaptive* parameters.
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.. function:: get_instructions(x, *, first_line=None, show_caches=False, adaptive=False)
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Return an iterator over the instructions in the supplied function, method,
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source code string or code object.
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The iterator generates a series of :class:`Instruction` named tuples giving
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the details of each operation in the supplied code.
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If *first_line* is not ``None``, it indicates the line number that should be
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reported for the first source line in the disassembled code. Otherwise, the
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source line information (if any) is taken directly from the disassembled code
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object.
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The *show_caches* and *adaptive* parameters work as they do in :func:`dis`.
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.. versionadded:: 3.4
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.. versionchanged:: 3.11
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Added the *show_caches* and *adaptive* parameters.
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.. function:: findlinestarts(code)
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This generator function uses the ``co_lines`` method
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of the code object *code* to find the offsets which are starts of
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lines in the source code. They are generated as ``(offset, lineno)`` pairs.
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.. versionchanged:: 3.6
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Line numbers can be decreasing. Before, they were always increasing.
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.. versionchanged:: 3.10
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The :pep:`626` ``co_lines`` method is used instead of the ``co_firstlineno``
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and ``co_lnotab`` attributes of the code object.
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.. function:: findlabels(code)
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Detect all offsets in the raw compiled bytecode string *code* which are jump targets, and
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return a list of these offsets.
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.. function:: stack_effect(opcode, oparg=None, *, jump=None)
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Compute the stack effect of *opcode* with argument *oparg*.
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If the code has a jump target and *jump* is ``True``, :func:`~stack_effect`
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will return the stack effect of jumping. If *jump* is ``False``,
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it will return the stack effect of not jumping. And if *jump* is
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``None`` (default), it will return the maximal stack effect of both cases.
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.. versionadded:: 3.4
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.. versionchanged:: 3.8
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Added *jump* parameter.
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.. versionchanged:: 3.13
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If ``oparg`` is omitted (or ``None``), the stack effect is now returned
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for ``oparg=0``. Previously this was an error for opcodes that use their
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arg. It is also no longer an error to pass an integer ``oparg`` when
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the ``opcode`` does not use it; the ``oparg`` in this case is ignored.
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.. _bytecodes:
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Python Bytecode Instructions
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----------------------------
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The :func:`get_instructions` function and :class:`Bytecode` class provide
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details of bytecode instructions as :class:`Instruction` instances:
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.. class:: Instruction
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Details for a bytecode operation
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.. data:: opcode
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numeric code for operation, corresponding to the opcode values listed
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below and the bytecode values in the :ref:`opcode_collections`.
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.. data:: opname
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human readable name for operation
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.. data:: baseopcode
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numeric code for the base operation if operation is specialized;
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otherwise equal to :data:`opcode`
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.. data:: baseopname
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human readable name for the base operation if operation is specialized;
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otherwise equal to :data:`opname`
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.. data:: arg
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numeric argument to operation (if any), otherwise ``None``
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.. data:: oparg
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alias for :data:`arg`
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.. data:: argval
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resolved arg value (if any), otherwise ``None``
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.. data:: argrepr
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human readable description of operation argument (if any),
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otherwise an empty string.
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.. data:: offset
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start index of operation within bytecode sequence
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.. data:: start_offset
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start index of operation within bytecode sequence, including prefixed
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``EXTENDED_ARG`` operations if present; otherwise equal to :data:`offset`
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.. data:: cache_offset
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start index of the cache entries following the operation
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.. data:: end_offset
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end index of the cache entries following the operation
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.. data:: starts_line
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line started by this opcode (if any), otherwise ``None``
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.. data:: is_jump_target
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``True`` if other code jumps to here, otherwise ``False``
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.. data:: jump_target
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bytecode index of the jump target if this is a jump operation,
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otherwise ``None``
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.. data:: positions
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:class:`dis.Positions` object holding the
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start and end locations that are covered by this instruction.
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.. versionadded:: 3.4
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.. versionchanged:: 3.11
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Field ``positions`` is added.
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.. versionchanged:: 3.13
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Added fields ``start_offset``, ``cache_offset``, ``end_offset``,
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``baseopname``, ``baseopcode``, ``jump_target`` and ``oparg``.
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.. class:: Positions
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In case the information is not available, some fields might be ``None``.
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.. data:: lineno
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.. data:: end_lineno
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.. data:: col_offset
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.. data:: end_col_offset
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.. versionadded:: 3.11
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The Python compiler currently generates the following bytecode instructions.
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**General instructions**
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In the following, We will refer to the interpreter stack as ``STACK`` and describe
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operations on it as if it was a Python list. The top of the stack corresponds to
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``STACK[-1]`` in this language.
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.. opcode:: NOP
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Do nothing code. Used as a placeholder by the bytecode optimizer, and to
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generate line tracing events.
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.. opcode:: POP_TOP
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Removes the top-of-stack item::
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STACK.pop()
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.. opcode:: END_FOR
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Removes the top two values from the stack.
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Equivalent to ``POP_TOP``; ``POP_TOP``.
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Used to clean up at the end of loops, hence the name.
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.. versionadded:: 3.12
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.. opcode:: COPY (i)
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Push the i-th item to the top of the stack without removing it from its original
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location::
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assert i > 0
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STACK.append(STACK[-i])
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.. versionadded:: 3.11
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.. opcode:: SWAP (i)
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Swap the top of the stack with the i-th element::
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STACK[-i], STACK[-1] = stack[-1], STACK[-i]
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.. versionadded:: 3.11
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.. opcode:: CACHE
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Rather than being an actual instruction, this opcode is used to mark extra
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space for the interpreter to cache useful data directly in the bytecode
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itself. It is automatically hidden by all ``dis`` utilities, but can be
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viewed with ``show_caches=True``.
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Logically, this space is part of the preceding instruction. Many opcodes
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expect to be followed by an exact number of caches, and will instruct the
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interpreter to skip over them at runtime.
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Populated caches can look like arbitrary instructions, so great care should
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be taken when reading or modifying raw, adaptive bytecode containing
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quickened data.
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.. versionadded:: 3.11
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**Unary operations**
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Unary operations take the top of the stack, apply the operation, and push the
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result back on the stack.
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.. opcode:: UNARY_NEGATIVE
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Implements ``STACK[-1] = -STACK[-1]``.
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.. opcode:: UNARY_NOT
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Implements ``STACK[-1] = not STACK[-1]``.
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.. versionchanged:: 3.13
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This instruction now requires an exact :class:`bool` operand.
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.. opcode:: UNARY_INVERT
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Implements ``STACK[-1] = ~STACK[-1]``.
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.. opcode:: GET_ITER
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Implements ``STACK[-1] = iter(STACK[-1])``.
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.. opcode:: GET_YIELD_FROM_ITER
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If ``STACK[-1]`` is a :term:`generator iterator` or :term:`coroutine` object
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it is left as is. Otherwise, implements ``STACK[-1] = iter(STACK[-1])``.
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.. versionadded:: 3.5
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.. opcode:: TO_BOOL
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Implements ``STACK[-1] = bool(STACK[-1])``.
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.. versionadded:: 3.13
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**Binary and in-place operations**
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Binary operations remove the top two items from the stack (``STACK[-1]`` and
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``STACK[-2]``). They perform the operation, then put the result back on the stack.
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In-place operations are like binary operations, but the operation is done in-place
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when ``STACK[-2]`` supports it, and the resulting ``STACK[-1]`` may be (but does
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not have to be) the original ``STACK[-2]``.
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.. opcode:: BINARY_OP (op)
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Implements the binary and in-place operators (depending on the value of
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*op*)::
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rhs = STACK.pop()
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lhs = STACK.pop()
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STACK.append(lhs op rhs)
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.. versionadded:: 3.11
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.. opcode:: BINARY_SUBSCR
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Implements::
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key = STACK.pop()
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container = STACK.pop()
|
|
STACK.append(container[index])
|
|
|
|
|
|
.. opcode:: STORE_SUBSCR
|
|
|
|
Implements::
|
|
|
|
key = STACK.pop()
|
|
container = STACK.pop()
|
|
value = STACK.pop()
|
|
container[key] = value
|
|
|
|
|
|
.. opcode:: DELETE_SUBSCR
|
|
|
|
Implements::
|
|
|
|
key = STACK.pop()
|
|
container = STACK.pop()
|
|
del container[key]
|
|
|
|
.. opcode:: BINARY_SLICE
|
|
|
|
Implements::
|
|
|
|
end = STACK.pop()
|
|
start = STACK.pop()
|
|
container = STACK.pop()
|
|
STACK.append(container[start:end])
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
|
|
.. opcode:: STORE_SLICE
|
|
|
|
Implements::
|
|
|
|
end = STACK.pop()
|
|
start = STACK.pop()
|
|
container = STACK.pop()
|
|
values = STACK.pop()
|
|
container[start:end] = value
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
|
|
**Coroutine opcodes**
|
|
|
|
.. opcode:: GET_AWAITABLE (where)
|
|
|
|
Implements ``STACK[-1] = get_awaitable(STACK[-1])``, where ``get_awaitable(o)``
|
|
returns ``o`` if ``o`` is a coroutine object or a generator object with
|
|
the :data:`~inspect.CO_ITERABLE_COROUTINE` flag, or resolves
|
|
``o.__await__``.
|
|
|
|
If the ``where`` operand is nonzero, it indicates where the instruction
|
|
occurs:
|
|
|
|
* ``1``: After a call to ``__aenter__``
|
|
* ``2``: After a call to ``__aexit__``
|
|
|
|
.. versionadded:: 3.5
|
|
|
|
.. versionchanged:: 3.11
|
|
Previously, this instruction did not have an oparg.
|
|
|
|
|
|
.. opcode:: GET_AITER
|
|
|
|
Implements ``STACK[-1] = STACK[-1].__aiter__()``.
|
|
|
|
.. versionadded:: 3.5
|
|
.. versionchanged:: 3.7
|
|
Returning awaitable objects from ``__aiter__`` is no longer
|
|
supported.
|
|
|
|
|
|
.. opcode:: GET_ANEXT
|
|
|
|
Implement ``STACK.append(get_awaitable(STACK[-1].__anext__()))`` to the stack.
|
|
See ``GET_AWAITABLE`` for details about ``get_awaitable``.
|
|
|
|
.. versionadded:: 3.5
|
|
|
|
|
|
.. opcode:: END_ASYNC_FOR
|
|
|
|
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.
|
|
|
|
.. versionadded:: 3.8
|
|
|
|
.. versionchanged:: 3.11
|
|
Exception representation on the stack now consist of one, not three, items.
|
|
|
|
|
|
.. opcode:: CLEANUP_THROW
|
|
|
|
Handles an exception raised during a :meth:`~generator.throw` or
|
|
:meth:`~generator.close` call through the current frame. If ``STACK[-1]`` is an
|
|
instance of :exc:`StopIteration`, pop three values from the stack and push
|
|
its ``value`` member. Otherwise, re-raise ``STACK[-1]``.
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
|
|
.. opcode:: BEFORE_ASYNC_WITH
|
|
|
|
Resolves ``__aenter__`` and ``__aexit__`` from ``STACK[-1]``.
|
|
Pushes ``__aexit__`` and result of ``__aenter__()`` to the stack::
|
|
|
|
STACK.extend((__aexit__, __aenter__())
|
|
|
|
.. versionadded:: 3.5
|
|
|
|
|
|
|
|
**Miscellaneous opcodes**
|
|
|
|
.. opcode:: SET_ADD (i)
|
|
|
|
Implements::
|
|
|
|
item = STACK.pop()
|
|
set.add(STACK[-i], item)
|
|
|
|
Used to implement set comprehensions.
|
|
|
|
|
|
.. opcode:: LIST_APPEND (i)
|
|
|
|
Implements::
|
|
|
|
item = STACK.pop()
|
|
list.append(STACK[-i], item)
|
|
|
|
Used to implement list comprehensions.
|
|
|
|
|
|
.. opcode:: MAP_ADD (i)
|
|
|
|
Implements::
|
|
|
|
value = STACK.pop()
|
|
key = STACK.pop()
|
|
dict.__setitem__(STACK[-i], key, value)
|
|
|
|
Used to implement dict comprehensions.
|
|
|
|
.. versionadded:: 3.1
|
|
.. versionchanged:: 3.8
|
|
Map value is ``STACK[-1]`` and map key is ``STACK[-2]``. Before, those
|
|
were reversed.
|
|
|
|
For all of the :opcode:`SET_ADD`, :opcode:`LIST_APPEND` and :opcode:`MAP_ADD`
|
|
instructions, while the added value or key/value pair is popped off, the
|
|
container object remains on the stack so that it is available for further
|
|
iterations of the loop.
|
|
|
|
|
|
.. opcode:: RETURN_VALUE
|
|
|
|
Returns with ``STACK[-1]`` to the caller of the function.
|
|
|
|
|
|
.. opcode:: RETURN_CONST (consti)
|
|
|
|
Returns with ``co_consts[consti]`` to the caller of the function.
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
|
|
.. opcode:: YIELD_VALUE
|
|
|
|
Yields ``STACK.pop()`` from a :term:`generator`.
|
|
|
|
.. versionchanged:: 3.11
|
|
oparg set to be the stack depth.
|
|
|
|
.. versionchanged:: 3.12
|
|
oparg set to be the exception block depth, for efficient closing of generators.
|
|
|
|
|
|
.. opcode:: SETUP_ANNOTATIONS
|
|
|
|
Checks whether ``__annotations__`` is defined in ``locals()``, if not it is
|
|
set up to an empty ``dict``. This opcode is only emitted if a class
|
|
or module body contains :term:`variable annotations <variable annotation>`
|
|
statically.
|
|
|
|
.. versionadded:: 3.6
|
|
|
|
|
|
.. opcode:: POP_EXCEPT
|
|
|
|
Pops a value from the stack, which is used to restore the exception state.
|
|
|
|
.. versionchanged:: 3.11
|
|
Exception representation on the stack now consist of one, not three, items.
|
|
|
|
.. opcode:: RERAISE
|
|
|
|
Re-raises the exception currently on top of the stack. If oparg is non-zero,
|
|
pops an additional value from the stack which is used to set ``f_lasti``
|
|
of the current frame.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
.. versionchanged:: 3.11
|
|
Exception representation on the stack now consist of one, not three, items.
|
|
|
|
.. opcode:: PUSH_EXC_INFO
|
|
|
|
Pops a value from the stack. Pushes the current exception to the top of the stack.
|
|
Pushes the value originally popped back to the stack.
|
|
Used in exception handlers.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
.. opcode:: CHECK_EXC_MATCH
|
|
|
|
Performs exception matching for ``except``. Tests whether the ``STACK[-2]``
|
|
is an exception matching ``STACK[-1]``. Pops ``STACK[-1]`` and pushes the boolean
|
|
result of the test.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
.. opcode:: CHECK_EG_MATCH
|
|
|
|
Performs exception matching for ``except*``. Applies ``split(STACK[-1])`` on
|
|
the exception group representing ``STACK[-2]``.
|
|
|
|
In case of a match, pops two items from the stack and pushes the
|
|
non-matching subgroup (``None`` in case of full match) followed by the
|
|
matching subgroup. When there is no match, pops one item (the match
|
|
type) and pushes ``None``.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
.. opcode:: WITH_EXCEPT_START
|
|
|
|
Calls the function in position 4 on the stack with arguments (type, val, tb)
|
|
representing the exception at the top of the stack.
|
|
Used to implement the call ``context_manager.__exit__(*exc_info())`` when an exception
|
|
has occurred in a :keyword:`with` statement.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
.. versionchanged:: 3.11
|
|
The ``__exit__`` function is in position 4 of the stack rather than 7.
|
|
Exception representation on the stack now consist of one, not three, items.
|
|
|
|
|
|
.. opcode:: LOAD_ASSERTION_ERROR
|
|
|
|
Pushes :exc:`AssertionError` onto the stack. Used by the :keyword:`assert`
|
|
statement.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
|
|
.. opcode:: LOAD_BUILD_CLASS
|
|
|
|
Pushes :func:`builtins.__build_class__` onto the stack. It is later called
|
|
to construct a class.
|
|
|
|
|
|
.. opcode:: BEFORE_WITH
|
|
|
|
This opcode performs several operations before a with block starts. First,
|
|
it loads :meth:`~object.__exit__` from the context manager and pushes it onto
|
|
the stack for later use by :opcode:`WITH_EXCEPT_START`. Then,
|
|
:meth:`~object.__enter__` is called. Finally, the result of calling the
|
|
``__enter__()`` method is pushed onto the stack.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: GET_LEN
|
|
|
|
Perform ``STACK.append(len(STACK[-1]))``.
|
|
|
|
.. versionadded:: 3.10
|
|
|
|
|
|
.. opcode:: MATCH_MAPPING
|
|
|
|
If ``STACK[-1]`` is an instance of :class:`collections.abc.Mapping` (or, more
|
|
technically: if it has the :const:`Py_TPFLAGS_MAPPING` flag set in its
|
|
:c:member:`~PyTypeObject.tp_flags`), push ``True`` onto the stack. Otherwise,
|
|
push ``False``.
|
|
|
|
.. versionadded:: 3.10
|
|
|
|
|
|
.. opcode:: MATCH_SEQUENCE
|
|
|
|
If ``STACK[-1]`` is an instance of :class:`collections.abc.Sequence` and is *not* an instance
|
|
of :class:`str`/:class:`bytes`/:class:`bytearray` (or, more technically: if it has
|
|
the :const:`Py_TPFLAGS_SEQUENCE` flag set in its :c:member:`~PyTypeObject.tp_flags`),
|
|
push ``True`` onto the stack. Otherwise, push ``False``.
|
|
|
|
.. versionadded:: 3.10
|
|
|
|
|
|
.. opcode:: MATCH_KEYS
|
|
|
|
``STACK[-1]`` is a tuple of mapping keys, and ``STACK[-2]`` is the match subject.
|
|
If ``STACK[-2]`` contains all of the keys in ``STACK[-1]``, push a :class:`tuple`
|
|
containing the corresponding values. Otherwise, push ``None``.
|
|
|
|
.. versionadded:: 3.10
|
|
|
|
.. versionchanged:: 3.11
|
|
Previously, this instruction also pushed a boolean value indicating
|
|
success (``True``) or failure (``False``).
|
|
|
|
|
|
.. opcode:: STORE_NAME (namei)
|
|
|
|
Implements ``name = STACK.pop()``. *namei* is the index of *name* in the attribute
|
|
:attr:`co_names` of the code object. The compiler tries to use
|
|
:opcode:`STORE_FAST` or :opcode:`STORE_GLOBAL` if possible.
|
|
|
|
|
|
.. opcode:: DELETE_NAME (namei)
|
|
|
|
Implements ``del name``, where *namei* is the index into :attr:`co_names`
|
|
attribute of the code object.
|
|
|
|
|
|
.. opcode:: UNPACK_SEQUENCE (count)
|
|
|
|
Unpacks ``STACK[-1]`` into *count* individual values, which are put onto the stack
|
|
right-to-left::
|
|
|
|
STACK.extend(STACK.pop()[:count:-1])
|
|
|
|
|
|
.. opcode:: UNPACK_EX (counts)
|
|
|
|
Implements assignment with a starred target: Unpacks an iterable in ``STACK[-1]``
|
|
into individual values, where the total number of values can be smaller than the
|
|
number of items in the iterable: one of the new values will be a list of all
|
|
leftover items.
|
|
|
|
The number of values before and after the list value is limited to 255.
|
|
|
|
The number of values before the list value is encoded in the argument of the
|
|
opcode. The number of values after the list if any is encoded using an
|
|
``EXTENDED_ARG``. As a consequence, the argument can be seen as a two bytes values
|
|
where the low byte of *counts* is the number of values before the list value, the
|
|
high byte of *counts* the number of values after it.
|
|
|
|
The extracted values are put onto the stack right-to-left, i.e. ``a, *b, c = d``
|
|
will be stored after execution as ``STACK.extend((a, b, c))``.
|
|
|
|
|
|
.. opcode:: STORE_ATTR (namei)
|
|
|
|
Implements::
|
|
|
|
obj = STACK.pop()
|
|
value = STACK.pop()
|
|
obj.name = value
|
|
|
|
where *namei* is the index of name in :attr:`co_names`.
|
|
|
|
.. opcode:: DELETE_ATTR (namei)
|
|
|
|
Implements::
|
|
|
|
obj = STACK.pop()
|
|
del obj.name
|
|
|
|
where *namei* is the index of name into :attr:`co_names`.
|
|
|
|
|
|
.. opcode:: STORE_GLOBAL (namei)
|
|
|
|
Works as :opcode:`STORE_NAME`, but stores the name as a global.
|
|
|
|
|
|
.. opcode:: DELETE_GLOBAL (namei)
|
|
|
|
Works as :opcode:`DELETE_NAME`, but deletes a global name.
|
|
|
|
|
|
.. opcode:: LOAD_CONST (consti)
|
|
|
|
Pushes ``co_consts[consti]`` onto the stack.
|
|
|
|
|
|
.. opcode:: LOAD_NAME (namei)
|
|
|
|
Pushes the value associated with ``co_names[namei]`` onto the stack.
|
|
The name is looked up within the locals, then the globals, then the builtins.
|
|
|
|
|
|
.. opcode:: LOAD_LOCALS
|
|
|
|
Pushes a reference to the locals dictionary onto the stack. This is used
|
|
to prepare namespace dictionaries for :opcode:`LOAD_FROM_DICT_OR_DEREF`
|
|
and :opcode:`LOAD_FROM_DICT_OR_GLOBALS`.
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
|
|
.. opcode:: LOAD_FROM_DICT_OR_GLOBALS (i)
|
|
|
|
Pops a mapping off the stack and looks up the value for ``co_names[namei]``.
|
|
If the name is not found there, looks it up in the globals and then the builtins,
|
|
similar to :opcode:`LOAD_GLOBAL`.
|
|
This is used for loading global variables in
|
|
:ref:`annotation scopes <annotation-scopes>` within class bodies.
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
|
|
.. opcode:: BUILD_TUPLE (count)
|
|
|
|
Creates a tuple consuming *count* items from the stack, and pushes the
|
|
resulting tuple onto the stack.::
|
|
|
|
assert count > 0
|
|
STACK, values = STACK[:-count], STACK[-count:]
|
|
STACK.append(tuple(values))
|
|
|
|
|
|
.. opcode:: BUILD_LIST (count)
|
|
|
|
Works as :opcode:`BUILD_TUPLE`, but creates a list.
|
|
|
|
|
|
.. opcode:: BUILD_SET (count)
|
|
|
|
Works as :opcode:`BUILD_TUPLE`, but creates a set.
|
|
|
|
|
|
.. opcode:: BUILD_MAP (count)
|
|
|
|
Pushes a new dictionary object onto the stack. Pops ``2 * count`` items
|
|
so that the dictionary holds *count* entries:
|
|
``{..., STACK[-4]: STACK[-3], STACK[-2]: STACK[-1]}``.
|
|
|
|
.. versionchanged:: 3.5
|
|
The dictionary is created from stack items instead of creating an
|
|
empty dictionary pre-sized to hold *count* items.
|
|
|
|
|
|
.. opcode:: BUILD_CONST_KEY_MAP (count)
|
|
|
|
The version of :opcode:`BUILD_MAP` specialized for constant keys. Pops the
|
|
top element on the stack which contains a tuple of keys, then starting from
|
|
``STACK[-2]``, pops *count* values to form values in the built dictionary.
|
|
|
|
.. versionadded:: 3.6
|
|
|
|
|
|
.. opcode:: BUILD_STRING (count)
|
|
|
|
Concatenates *count* strings from the stack and pushes the resulting string
|
|
onto the stack.
|
|
|
|
.. versionadded:: 3.6
|
|
|
|
|
|
.. opcode:: LIST_EXTEND (i)
|
|
|
|
Implements::
|
|
|
|
seq = STACK.pop()
|
|
list.extend(STACK[-i], seq)
|
|
|
|
Used to build lists.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
|
|
.. opcode:: SET_UPDATE (i)
|
|
|
|
Implements::
|
|
|
|
seq = STACK.pop()
|
|
set.update(STACK[-i], seq)
|
|
|
|
Used to build sets.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
|
|
.. opcode:: DICT_UPDATE (i)
|
|
|
|
Implements::
|
|
|
|
map = STACK.pop()
|
|
dict.update(STACK[-i], map)
|
|
|
|
Used to build dicts.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
|
|
.. opcode:: DICT_MERGE (i)
|
|
|
|
Like :opcode:`DICT_UPDATE` but raises an exception for duplicate keys.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
|
|
.. 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])``.
|
|
|
|
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.
|
|
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`
|
|
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.
|
|
|
|
|
|
.. opcode:: LOAD_SUPER_ATTR (namei)
|
|
|
|
This opcode implements :func:`super` (e.g. ``super().method()`` and
|
|
``super().attr``). It works the same as :opcode:`LOAD_ATTR`, except that
|
|
``namei`` is shifted left by 2 bits instead of 1, and instead of expecting a
|
|
single receiver on the stack, it expects three objects (from top of stack
|
|
down): ``self`` (the first argument to the current method), ``cls`` (the
|
|
class within which the current method was defined), and the global ``super``.
|
|
|
|
The low bit of ``namei`` signals to attempt a method load, as with
|
|
:opcode:`LOAD_ATTR`.
|
|
|
|
The second-low bit of ``namei``, if set, means that this was a two-argument
|
|
call to :func:`super` (unset means zero-argument).
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
|
|
.. opcode:: COMPARE_OP (opname)
|
|
|
|
Performs a Boolean operation. The operation name can be found in
|
|
``cmp_op[opname >> 5]``. If the fifth-lowest bit of ``opname`` is set
|
|
(``opname & 16``), the result should be coerced to ``bool``.
|
|
|
|
.. versionchanged:: 3.13
|
|
The fifth-lowest bit of the oparg now indicates a forced conversion to
|
|
:class:`bool`.
|
|
|
|
|
|
.. opcode:: IS_OP (invert)
|
|
|
|
Performs ``is`` comparison, or ``is not`` if ``invert`` is 1.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
|
|
.. opcode:: CONTAINS_OP (invert)
|
|
|
|
Performs ``in`` comparison, or ``not in`` if ``invert`` is 1.
|
|
|
|
.. versionadded:: 3.9
|
|
|
|
|
|
.. opcode:: IMPORT_NAME (namei)
|
|
|
|
Imports the module ``co_names[namei]``. ``STACK[-1]`` and ``STACK[-2]`` are
|
|
popped and provide the *fromlist* and *level* arguments of :func:`__import__`.
|
|
The module object is pushed onto the stack. The current namespace is not affected: for a proper import statement, a subsequent :opcode:`STORE_FAST` instruction
|
|
modifies the namespace.
|
|
|
|
|
|
.. opcode:: IMPORT_FROM (namei)
|
|
|
|
Loads the attribute ``co_names[namei]`` from the module found in ``STACK[-1]``.
|
|
The resulting object is pushed onto the stack, to be subsequently stored by a
|
|
:opcode:`STORE_FAST` instruction.
|
|
|
|
|
|
.. opcode:: JUMP_FORWARD (delta)
|
|
|
|
Increments bytecode counter by *delta*.
|
|
|
|
|
|
.. opcode:: JUMP_BACKWARD (delta)
|
|
|
|
Decrements bytecode counter by *delta*. Checks for interrupts.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: JUMP_BACKWARD_NO_INTERRUPT (delta)
|
|
|
|
Decrements bytecode counter by *delta*. Does not check for interrupts.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: POP_JUMP_IF_TRUE (delta)
|
|
|
|
If ``STACK[-1]`` is true, increments the bytecode counter by *delta*.
|
|
``STACK[-1]`` is popped.
|
|
|
|
.. versionchanged:: 3.11
|
|
The oparg is now a relative delta rather than an absolute target.
|
|
This opcode is a pseudo-instruction, replaced in final bytecode by
|
|
the directed versions (forward/backward).
|
|
|
|
.. versionchanged:: 3.12
|
|
This is no longer a pseudo-instruction.
|
|
|
|
.. versionchanged:: 3.13
|
|
This instruction now requires an exact :class:`bool` operand.
|
|
|
|
.. opcode:: POP_JUMP_IF_FALSE (delta)
|
|
|
|
If ``STACK[-1]`` is false, increments the bytecode counter by *delta*.
|
|
``STACK[-1]`` is popped.
|
|
|
|
.. versionchanged:: 3.11
|
|
The oparg is now a relative delta rather than an absolute target.
|
|
This opcode is a pseudo-instruction, replaced in final bytecode by
|
|
the directed versions (forward/backward).
|
|
|
|
.. versionchanged:: 3.12
|
|
This is no longer a pseudo-instruction.
|
|
|
|
.. versionchanged:: 3.13
|
|
This instruction now requires an exact :class:`bool` operand.
|
|
|
|
.. opcode:: POP_JUMP_IF_NOT_NONE (delta)
|
|
|
|
If ``STACK[-1]`` is not ``None``, increments the bytecode counter by *delta*.
|
|
``STACK[-1]`` is popped.
|
|
|
|
This opcode is a pseudo-instruction, replaced in final bytecode by
|
|
the directed versions (forward/backward).
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
.. versionchanged:: 3.12
|
|
This is no longer a pseudo-instruction.
|
|
|
|
|
|
.. opcode:: POP_JUMP_IF_NONE (delta)
|
|
|
|
If ``STACK[-1]`` is ``None``, increments the bytecode counter by *delta*.
|
|
``STACK[-1]`` is popped.
|
|
|
|
This opcode is a pseudo-instruction, replaced in final bytecode by
|
|
the directed versions (forward/backward).
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
.. versionchanged:: 3.12
|
|
This is no longer a pseudo-instruction.
|
|
|
|
.. opcode:: FOR_ITER (delta)
|
|
|
|
``STACK[-1]`` is an :term:`iterator`. Call its :meth:`~iterator.__next__` method.
|
|
If this yields a new value, push it on the stack (leaving the iterator below
|
|
it). If the iterator indicates it is exhausted then the byte code counter is
|
|
incremented by *delta*.
|
|
|
|
.. versionchanged:: 3.12
|
|
Up until 3.11 the iterator was popped when it was exhausted.
|
|
|
|
.. opcode:: LOAD_GLOBAL (namei)
|
|
|
|
Loads the global named ``co_names[namei>>1]`` onto the stack.
|
|
|
|
.. versionchanged:: 3.11
|
|
If the low bit of ``namei`` is set, then a ``NULL`` is pushed to the
|
|
stack before the global variable.
|
|
|
|
.. opcode:: LOAD_FAST (var_num)
|
|
|
|
Pushes a reference to the local ``co_varnames[var_num]`` onto the stack.
|
|
|
|
.. versionchanged:: 3.12
|
|
This opcode is now only used in situations where the local variable is
|
|
guaranteed to be initialized. It cannot raise :exc:`UnboundLocalError`.
|
|
|
|
.. opcode:: LOAD_FAST_CHECK (var_num)
|
|
|
|
Pushes a reference to the local ``co_varnames[var_num]`` onto the stack,
|
|
raising an :exc:`UnboundLocalError` if the local variable has not been
|
|
initialized.
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
.. opcode:: LOAD_FAST_AND_CLEAR (var_num)
|
|
|
|
Pushes a reference to the local ``co_varnames[var_num]`` onto the stack (or
|
|
pushes ``NULL`` onto the stack if the local variable has not been
|
|
initialized) and sets ``co_varnames[var_num]`` to ``NULL``.
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
.. opcode:: STORE_FAST (var_num)
|
|
|
|
Stores ``STACK.pop()`` into the local ``co_varnames[var_num]``.
|
|
|
|
|
|
.. opcode:: DELETE_FAST (var_num)
|
|
|
|
Deletes local ``co_varnames[var_num]``.
|
|
|
|
|
|
.. opcode:: MAKE_CELL (i)
|
|
|
|
Creates a new cell in slot ``i``. If that slot is nonempty then
|
|
that value is stored into the new cell.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: LOAD_DEREF (i)
|
|
|
|
Loads the cell contained in slot ``i`` of the "fast locals" storage.
|
|
Pushes a reference to the object the cell contains on the stack.
|
|
|
|
.. versionchanged:: 3.11
|
|
``i`` is no longer offset by the length of ``co_varnames``.
|
|
|
|
|
|
.. opcode:: LOAD_FROM_DICT_OR_DEREF (i)
|
|
|
|
Pops a mapping off the stack and looks up the name associated with
|
|
slot ``i`` of the "fast locals" storage in this mapping.
|
|
If the name is not found there, loads it from the cell contained in
|
|
slot ``i``, similar to :opcode:`LOAD_DEREF`. This is used for loading
|
|
free variables in class bodies (which previously used
|
|
:opcode:`!LOAD_CLASSDEREF`) and in
|
|
:ref:`annotation scopes <annotation-scopes>` within class bodies.
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
|
|
.. opcode:: STORE_DEREF (i)
|
|
|
|
Stores ``STACK.pop()`` into the cell contained in slot ``i`` of the "fast locals"
|
|
storage.
|
|
|
|
.. versionchanged:: 3.11
|
|
``i`` is no longer offset by the length of ``co_varnames``.
|
|
|
|
|
|
.. opcode:: DELETE_DEREF (i)
|
|
|
|
Empties the cell contained in slot ``i`` of the "fast locals" storage.
|
|
Used by the :keyword:`del` statement.
|
|
|
|
.. versionadded:: 3.2
|
|
|
|
.. versionchanged:: 3.11
|
|
``i`` is no longer offset by the length of ``co_varnames``.
|
|
|
|
|
|
.. opcode:: COPY_FREE_VARS (n)
|
|
|
|
Copies the ``n`` free variables from the closure into the frame.
|
|
Removes the need for special code on the caller's side when calling
|
|
closures.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: RAISE_VARARGS (argc)
|
|
|
|
Raises an exception using one of the 3 forms of the ``raise`` statement,
|
|
depending on the value of *argc*:
|
|
|
|
* 0: ``raise`` (re-raise previous exception)
|
|
* 1: ``raise STACK[-1]`` (raise exception instance or type at ``STACK[-1]``)
|
|
* 2: ``raise STACK[-2] from STACK[-1]`` (raise exception instance or type at
|
|
``STACK[-2]`` with ``__cause__`` set to ``STACK[-1]``)
|
|
|
|
|
|
.. opcode:: CALL (argc)
|
|
|
|
Calls a callable object with the number of arguments specified by ``argc``,
|
|
including the named arguments specified by the preceding
|
|
:opcode:`KW_NAMES`, if any.
|
|
On the stack are (in ascending order), either:
|
|
|
|
* NULL
|
|
* The callable
|
|
* The positional arguments
|
|
* The named arguments
|
|
|
|
or:
|
|
|
|
* The callable
|
|
* ``self``
|
|
* The remaining positional arguments
|
|
* The named arguments
|
|
|
|
``argc`` is the total of the positional and named arguments, excluding
|
|
``self`` when a ``NULL`` is not present.
|
|
|
|
``CALL`` pops all arguments and the callable object off the stack,
|
|
calls the callable object with those arguments, and pushes the return value
|
|
returned by the callable object.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: CALL_FUNCTION_EX (flags)
|
|
|
|
Calls a callable object with variable set of positional and keyword
|
|
arguments. If the lowest bit of *flags* is set, the top of the stack
|
|
contains a mapping object containing additional keyword arguments.
|
|
Before the callable is called, the mapping object and iterable object
|
|
are each "unpacked" and their contents passed in as keyword and
|
|
positional arguments respectively.
|
|
``CALL_FUNCTION_EX`` pops all arguments and the callable object off the stack,
|
|
calls the callable object with those arguments, and pushes the return value
|
|
returned by the callable object.
|
|
|
|
.. versionadded:: 3.6
|
|
|
|
|
|
.. opcode:: PUSH_NULL
|
|
|
|
Pushes a ``NULL`` to the stack.
|
|
Used in the call sequence to match the ``NULL`` pushed by
|
|
:opcode:`LOAD_METHOD` for non-method calls.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: KW_NAMES (consti)
|
|
|
|
Prefixes :opcode:`CALL`.
|
|
Stores a reference to ``co_consts[consti]`` into an internal variable
|
|
for use by :opcode:`CALL`. ``co_consts[consti]`` must be a tuple of strings.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: MAKE_FUNCTION
|
|
|
|
Pushes a new function object on the stack built from the code object at ``STACK[1]``.
|
|
|
|
.. versionchanged:: 3.10
|
|
Flag value ``0x04`` is a tuple of strings instead of dictionary
|
|
|
|
.. versionchanged:: 3.11
|
|
Qualified name at ``STACK[-1]`` was removed.
|
|
|
|
.. versionchanged:: 3.13
|
|
Extra function attributes on the stack, signaled by oparg flags, were
|
|
removed. They now use :opcode:`SET_FUNCTION_ATTRIBUTE`.
|
|
|
|
|
|
.. opcode:: SET_FUNCTION_ATTRIBUTE (flag)
|
|
|
|
Sets an attribute on a function object. Expects the function at ``STACK[-1]``
|
|
and the attribute value to set at ``STACK[-2]``; consumes both and leaves the
|
|
function at ``STACK[-1]``. The flag determines which attribute to set:
|
|
|
|
* ``0x01`` a tuple of default values for positional-only and
|
|
positional-or-keyword parameters in positional order
|
|
* ``0x02`` a dictionary of keyword-only parameters' default values
|
|
* ``0x04`` a tuple of strings containing parameters' annotations
|
|
* ``0x08`` a tuple containing cells for free variables, making a closure
|
|
|
|
.. versionadded:: 3.13
|
|
|
|
|
|
.. opcode:: BUILD_SLICE (argc)
|
|
|
|
.. index:: pair: built-in function; slice
|
|
|
|
Pushes a slice object on the stack. *argc* must be 2 or 3. If it is 2, implements::
|
|
|
|
end = STACK.pop()
|
|
start = STACK.pop()
|
|
STACK.append(slice(start, stop))
|
|
|
|
if it is 3, implements::
|
|
|
|
step = STACK.pop()
|
|
end = STACK.pop()
|
|
start = STACK.pop()
|
|
STACK.append(slice(start, end, step))
|
|
|
|
See the :func:`slice` built-in function for more information.
|
|
|
|
|
|
.. opcode:: EXTENDED_ARG (ext)
|
|
|
|
Prefixes any opcode which has an argument too big to fit into the default one
|
|
byte. *ext* holds an additional byte which act as higher bits in the argument.
|
|
For each opcode, at most three prefixal ``EXTENDED_ARG`` are allowed, forming
|
|
an argument from two-byte to four-byte.
|
|
|
|
|
|
.. opcode:: CONVERT_VALUE (oparg)
|
|
|
|
Convert value to a string, depending on ``oparg``::
|
|
|
|
value = STACK.pop()
|
|
result = func(value)
|
|
STACK.push(result)
|
|
|
|
* ``oparg == 1``: call :func:`str` on *value*
|
|
* ``oparg == 2``: call :func:`repr` on *value*
|
|
* ``oparg == 3``: call :func:`ascii` on *value*
|
|
|
|
Used for implementing formatted literal strings (f-strings).
|
|
|
|
.. versionadded:: 3.13
|
|
|
|
|
|
.. opcode:: FORMAT_SIMPLE
|
|
|
|
Formats the value on top of stack::
|
|
|
|
value = STACK.pop()
|
|
result = value.__format__("")
|
|
STACK.push(result)
|
|
|
|
Used for implementing formatted literal strings (f-strings).
|
|
|
|
.. versionadded:: 3.13
|
|
|
|
.. opcode:: FORMAT_SPEC
|
|
|
|
Formats the given value with the given format spec::
|
|
|
|
spec = STACK.pop()
|
|
value = STACK.pop()
|
|
result = value.__format__(spec)
|
|
STACK.push(result)
|
|
|
|
Used for implementing formatted literal strings (f-strings).
|
|
|
|
.. versionadded:: 3.13
|
|
|
|
|
|
.. opcode:: MATCH_CLASS (count)
|
|
|
|
``STACK[-1]`` is a tuple of keyword attribute names, ``STACK[-2]`` is the class
|
|
being matched against, and ``STACK[-3]`` is the match subject. *count* is the
|
|
number of positional sub-patterns.
|
|
|
|
Pop ``STACK[-1]``, ``STACK[-2]``, and ``STACK[-3]``. If ``STACK[-3]`` is an
|
|
instance of ``STACK[-2]`` and has the positional and keyword attributes
|
|
required by *count* and ``STACK[-1]``, push a tuple of extracted attributes.
|
|
Otherwise, push ``None``.
|
|
|
|
.. versionadded:: 3.10
|
|
|
|
.. versionchanged:: 3.11
|
|
Previously, this instruction also pushed a boolean value indicating
|
|
success (``True``) or failure (``False``).
|
|
|
|
|
|
.. opcode:: RESUME (where)
|
|
|
|
A no-op. Performs internal tracing, debugging and optimization checks.
|
|
|
|
The ``where`` operand marks where the ``RESUME`` occurs:
|
|
|
|
* ``0`` The start of a function, which is neither a generator, coroutine
|
|
nor an async generator
|
|
* ``1`` After a ``yield`` expression
|
|
* ``2`` After a ``yield from`` expression
|
|
* ``3`` After an ``await`` expression
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: RETURN_GENERATOR
|
|
|
|
Create a generator, coroutine, or async generator from the current frame.
|
|
Used as first opcode of in code object for the above mentioned callables.
|
|
Clear the current frame and return the newly created generator.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: SEND (delta)
|
|
|
|
Equivalent to ``STACK[-1] = STACK[-2].send(STACK[-1])``. Used in ``yield from``
|
|
and ``await`` statements.
|
|
|
|
If the call raises :exc:`StopIteration`, pop both items, push the
|
|
exception's ``value`` attribute, and increment the bytecode counter by
|
|
*delta*.
|
|
|
|
.. versionadded:: 3.11
|
|
|
|
|
|
.. opcode:: HAVE_ARGUMENT
|
|
|
|
This is not really an opcode. It identifies the dividing line between
|
|
opcodes in the range [0,255] which don't use their argument and those
|
|
that do (``< HAVE_ARGUMENT`` and ``>= HAVE_ARGUMENT``, respectively).
|
|
|
|
If your application uses pseudo instructions, use the :data:`hasarg`
|
|
collection instead.
|
|
|
|
.. versionchanged:: 3.6
|
|
Now every instruction has an argument, but opcodes ``< HAVE_ARGUMENT``
|
|
ignore it. Before, only opcodes ``>= HAVE_ARGUMENT`` had an argument.
|
|
|
|
.. versionchanged:: 3.12
|
|
Pseudo instructions were added to the :mod:`dis` module, and for them
|
|
it is not true that comparison with ``HAVE_ARGUMENT`` indicates whether
|
|
they use their arg.
|
|
|
|
|
|
.. opcode:: CALL_INTRINSIC_1
|
|
|
|
Calls an intrinsic function with one argument. Passes ``STACK[-1]`` as the
|
|
argument and sets ``STACK[-1]`` to the result. Used to implement
|
|
functionality that is necessary but not performance critical.
|
|
|
|
The operand determines which intrinsic function is called:
|
|
|
|
+-----------------------------------+-----------------------------------+
|
|
| Operand | Description |
|
|
+===================================+===================================+
|
|
| ``INTRINSIC_1_INVALID`` | Not valid |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_PRINT`` | Prints the argument to standard |
|
|
| | out. Used in the REPL. |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_IMPORT_STAR`` | Performs ``import *`` for the |
|
|
| | named module. |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_STOPITERATION_ERROR`` | Extracts the return value from a |
|
|
| | ``StopIteration`` exception. |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_ASYNC_GEN_WRAP`` | Wraps an aync generator value |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_UNARY_POSITIVE`` | Performs the unary ``+`` |
|
|
| | operation |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_LIST_TO_TUPLE`` | Converts a list to a tuple |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_TYPEVAR`` | Creates a :class:`typing.TypeVar` |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_PARAMSPEC`` | Creates a |
|
|
| | :class:`typing.ParamSpec` |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_TYPEVARTUPLE`` | Creates a |
|
|
| | :class:`typing.TypeVarTuple` |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_SUBSCRIPT_GENERIC`` | Returns :class:`typing.Generic` |
|
|
| | subscripted with the argument |
|
|
+-----------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_TYPEALIAS`` | Creates a |
|
|
| | :class:`typing.TypeAliasType`; |
|
|
| | used in the :keyword:`type` |
|
|
| | statement. The argument is a tuple|
|
|
| | of the type alias's name, |
|
|
| | type parameters, and value. |
|
|
+-----------------------------------+-----------------------------------+
|
|
|
|
.. versionadded:: 3.12
|
|
|
|
.. opcode:: CALL_INTRINSIC_2
|
|
|
|
Calls an intrinsic function with two arguments. Passes ``STACK[-2]``, ``STACK[-1]`` as the
|
|
arguments and sets ``STACK[-1]`` to the result. Used to implement functionality that is
|
|
necessary but not performance critical.
|
|
|
|
The operand determines which intrinsic function is called:
|
|
|
|
+----------------------------------------+-----------------------------------+
|
|
| Operand | Description |
|
|
+========================================+===================================+
|
|
| ``INTRINSIC_2_INVALID`` | Not valid |
|
|
+----------------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_PREP_RERAISE_STAR`` | Calculates the |
|
|
| | :exc:`ExceptionGroup` to raise |
|
|
| | from a ``try-except*``. |
|
|
+----------------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_TYPEVAR_WITH_BOUND`` | Creates a :class:`typing.TypeVar` |
|
|
| | with a bound. |
|
|
+----------------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_TYPEVAR_WITH_CONSTRAINTS`` | Creates a |
|
|
| | :class:`typing.TypeVar` with |
|
|
| | constraints. |
|
|
+----------------------------------------+-----------------------------------+
|
|
| ``INTRINSIC_SET_FUNCTION_TYPE_PARAMS`` | Sets the ``__type_params__`` |
|
|
| | attribute of a function. |
|
|
+----------------------------------------+-----------------------------------+
|
|
|
|
.. versionadded:: 3.12
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**Pseudo-instructions**
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These opcodes do not appear in Python bytecode. They are used by the compiler
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but are replaced by real opcodes or removed before bytecode is generated.
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.. opcode:: SETUP_FINALLY (target)
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Set up an exception handler for the following code block. If an exception
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occurs, the value stack level is restored to its current state and control
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is transferred to the exception handler at ``target``.
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.. opcode:: SETUP_CLEANUP (target)
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Like ``SETUP_FINALLY``, but in case of an exception also pushes the last
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instruction (``lasti``) to the stack so that ``RERAISE`` can restore it.
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If an exception occurs, the value stack level and the last instruction on
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the frame are restored to their current state, and control is transferred
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to the exception handler at ``target``.
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.. opcode:: SETUP_WITH (target)
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Like ``SETUP_CLEANUP``, but in case of an exception one more item is popped
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from the stack before control is transferred to the exception handler at
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``target``.
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This variant is used in :keyword:`with` and :keyword:`async with`
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constructs, which push the return value of the context manager's
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:meth:`~object.__enter__` or :meth:`~object.__aenter__` to the stack.
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.. opcode:: POP_BLOCK
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Marks the end of the code block associated with the last ``SETUP_FINALLY``,
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``SETUP_CLEANUP`` or ``SETUP_WITH``.
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.. opcode:: JUMP
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.. opcode:: JUMP_NO_INTERRUPT
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Undirected relative jump instructions which are replaced by their
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directed (forward/backward) counterparts by the assembler.
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.. opcode:: LOAD_CLOSURE (i)
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Pushes a reference to the cell contained in slot ``i`` of the "fast locals"
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storage.
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Note that ``LOAD_CLOSURE`` is replaced with ``LOAD_FAST`` in the assembler.
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.. versionchanged:: 3.13
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This opcode is now a pseudo-instruction.
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.. opcode:: LOAD_METHOD
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Optimized unbound method lookup. Emitted as a ``LOAD_ATTR`` opcode
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with a flag set in the arg.
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.. _opcode_collections:
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Opcode collections
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------------------
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These collections are provided for automatic introspection of bytecode
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instructions:
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.. versionchanged:: 3.12
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The collections now contain pseudo instructions as well. These are
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opcodes with values ``>= MIN_PSEUDO_OPCODE``.
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.. data:: opname
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Sequence of operation names, indexable using the bytecode.
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.. data:: opmap
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Dictionary mapping operation names to bytecodes.
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.. data:: cmp_op
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Sequence of all compare operation names.
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.. data:: hasarg
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Sequence of bytecodes that use their argument.
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.. versionadded:: 3.12
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.. data:: hasconst
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Sequence of bytecodes that access a constant.
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.. data:: hasfree
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Sequence of bytecodes that access a free variable. 'free' in this
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context refers to names in the current scope that are referenced by inner
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scopes or names in outer scopes that are referenced from this scope. It does
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*not* include references to global or builtin scopes.
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.. data:: hasname
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Sequence of bytecodes that access an attribute by name.
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.. data:: hasjump
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Sequence of bytecodes that have a jump target. All jumps
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are relative.
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.. versionadded:: 3.13
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.. data:: haslocal
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Sequence of bytecodes that access a local variable.
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.. data:: hascompare
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Sequence of bytecodes of Boolean operations.
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.. data:: hasexc
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Sequence of bytecodes that set an exception handler.
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.. versionadded:: 3.12
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.. data:: hasjrel
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Sequence of bytecodes that have a relative jump target.
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.. deprecated:: 3.13
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All jumps are now relative. Use :data:`hasjump`.
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.. data:: hasjabs
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Sequence of bytecodes that have an absolute jump target.
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.. deprecated:: 3.13
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All jumps are now relative. This list is empty.
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