Changes to the function version cache:
- In addition to the function object, also store the code object,
and allow the latter to be retrieved even if the function has been evicted.
- Stop assigning new function versions after a critical attribute (e.g. `__code__`)
has been modified; the version is permanently reset to zero in this case.
- Changes to `__annotations__` are no longer considered critical. (This fixes gh-109998.)
Changes to the Tier 2 optimization machinery:
- If we cannot map a function version to a function, but it is still mapped to a code object,
we continue projecting the trace.
The operand of the `_PUSH_FRAME` and `_POP_FRAME` opcodes can be either NULL,
a function object, or a code object with the lowest bit set.
This allows us to trace through code that calls an ephemeral function,
i.e., a function that may not be alive when we are constructing the executor,
e.g. a generator expression or certain nested functions.
We will lose globals removal inside such functions,
but we can still do other peephole operations
(and even possibly [call inlining](https://github.com/python/cpython/pull/116290),
if we decide to do it), which only need the code object.
As before, if we cannot retrieve the code object from the cache, we stop projecting.
Somehow we ended up with two separate counter variables tracking "the next function version".
Most likely this was a historical accident where an old branch was updated incorrectly.
This PR merges the two counters into a single one: `interp->func_state.next_version`.
Replace most of calls of _PyErr_WriteUnraisableMsg() and some
calls of PyErr_WriteUnraisable(NULL) with PyErr_FormatUnraisable().
Co-authored-by: Victor Stinner <vstinner@python.org>
It creates a modified copy of an object by calling the object's
__replace__() method.
It is a generalization of dataclasses.replace(), named tuple's _replace()
method and replace() methods in various classes, and supports all these
stdlib classes.
This finishes the work begun in gh-107760. When, while projecting a superblock, we encounter a call to a short, simple function, the superblock will now enter the function using `_PUSH_FRAME`, continue through it, and leave it using `_POP_FRAME`, and then continue through the original code. Multiple frame pushes and pops are even possible. It is also possible to stop appending to the superblock in the middle of a called function, when running out of space or encountering an unsupported bytecode.
* Add table describing possible executable classes for out-of-process debuggers.
* Remove shim code object creation code as it is no longer needed.
* Make lltrace a bit more robust w.r.t. non-standard frames.
* The majority of the monitoring code is in instrumentation.c
* The new instrumentation bytecodes are in bytecodes.c
* legacy_tracing.c adapts the new API to the old sys.setrace and sys.setprofile APIs
* Uses a better hashing algorithm to get better dispersion and remove commutativity.
* Incorporates `co_firstlineno`, `Py_SIZE(co)`, and bytecode instructions.
* This is now the entire set of criteria used in `code_richcompare`, except for `_PyCode_ConstantKey` (which would incorporate the types of `co_consts` rather than just their values).
* Add API to allow extensions to set callback function on creation and destruction of PyCodeObject
Co-authored-by: Ye11ow-Flash <janshah@cs.stonybrook.edu>
* code_sizeof() now uses an unsigned type (size_t) to compute the result.
* Fix _PyObject_ComputedDictPointer(): cast _PyObject_VAR_SIZE() to
Py_ssize_t, rather than long: it's a different type on 64-bit Windows.
* Clarify that _PyObject_VAR_SIZE() uses an unsigned type (size_t).
* Adds EXIT_INTERPRETER instruction to exit PyEval_EvalDefault()
* Simplifies RETURN_VALUE, YIELD_VALUE and RETURN_GENERATOR instructions as they no longer need to check for entry frames.
Move the following API from Include/opcode.h (public C API) to a new
Include/internal/pycore_opcode.h header file (internal C API):
* EXTRA_CASES
* _PyOpcode_Caches
* _PyOpcode_Deopt
* _PyOpcode_Jump
* _PyOpcode_OpName
* _PyOpcode_RelativeJump
* Stores all location info in linetable to conform to PEP 626.
* Remove column table from code objects.
* Remove end-line table from code objects.
* Document new location table format
Remove the Include/code.h header file. C extensions should only
include the main <Python.h> header file.
Python.h includes directly Include/cpython/code.h instead.
* Moves the bytecode to the end of the corresponding PyCodeObject, and quickens it in-place.
* Removes the almost-always-unused co_varnames, co_freevars, and co_cellvars member caches
* _PyOpcode_Deopt is a new mapping from all opcodes to their un-quickened forms.
* _PyOpcode_InlineCacheEntries is renamed to _PyOpcode_Caches
* _Py_IncrementCountAndMaybeQuicken is renamed to _PyCode_Warmup
* _Py_Quicken is renamed to _PyCode_Quicken
* _co_quickened is renamed to _co_code_adaptive (and is now a read-only memoryview).
* Do not emit unused nonzero opargs anymore in the compiler.
Rename private functions (no exported), add an underscore prefix:
* PyLineTable_InitAddressRange() => _PyLineTable_InitAddressRange()
* PyLineTable_NextAddressRange() => _PyLineTable_NextAddressRange()
* PyLineTable_PreviousAddressRange() => _PyLineTable_PreviousAddressRange()
Move private functions to the internal C API:
* _PyCode_Addr2EndLine()
* _PyCode_Addr2EndOffset()
* _PyCode_Addr2Offset()
* _PyCode_InitAddressRange()
* _PyCode_InitEndAddressRange(
* _PyLineTable_InitAddressRange()
* _PyLineTable_NextAddressRange()
* _PyLineTable_PreviousAddressRange()
No longer export the following internal functions:
* _PyCode_GetVarnames()
* _PyCode_GetCellvars()
* _PyCode_GetFreevars()
* _Py_GetSpecializationStats()
Add "extern" to pycore_code.h functions to identify them more easiliy
(they are still not exported).
Rename PyConfig.no_debug_ranges to PyConfig.code_debug_ranges and
invert the value.
Document -X no_debug_ranges and PYTHONNODEBUGRANGES env var in
PyConfig.code_debug_ranges documentation.
While the comment said 'We don't bother resizing localspluskinds',
this would cause .replace() to crash when it happened.
(Also types.CodeType(), but testing that is tedious, and this tests all
code paths.)
This PR is part of PEP 657 and augments the compiler to emit ending
line numbers as well as starting and ending columns from the AST
into compiled code objects. This allows bytecodes to be correlated
to the exact source code ranges that generated them.
This information is made available through the following public APIs:
* The `co_positions` method on code objects.
* The C API function `PyCode_Addr2Location`.
Co-authored-by: Batuhan Taskaya <isidentical@gmail.com>
Co-authored-by: Ammar Askar <ammar@ammaraskar.com>
Currently, if an arg value escapes (into the closure for an inner function) we end up allocating two indices in the fast locals even though only one gets used. Additionally, using the lower index would be better in some cases, such as with no-arg `super()`. To address this, we update the compiler to fix the offsets so each variable only gets one "fast local". As a consequence, now some cell offsets are interspersed with the locals (only when an arg escapes to an inner function).
https://bugs.python.org/issue43693
These were reverted in gh-26530 (commit 17c4edc) due to refleaks.
* 2c1e258 - Compute deref offsets in compiler (gh-25152)
* b2bf2bc - Add new internal code objects fields: co_fastlocalnames and co_fastlocalkinds. (gh-26388)
This change fixes the refleaks.
https://bugs.python.org/issue43693
* Add co_firstinstr field to code object.
* Implement barebones quickening.
* Use non-quickened bytecode when tracing.
* Add NEWS item
* Add new file to Windows build.
* Don't specialize instructions with EXTENDED_ARG.
* Revert "bpo-43693: Compute deref offsets in compiler (gh-25152)"
This reverts commit b2bf2bc1ec.
* Revert "bpo-43693: Add new internal code objects fields: co_fastlocalnames and co_fastlocalkinds. (gh-26388)"
This reverts commit 2c1e2583fd.
These two commits are breaking the refleak buildbots.
Merges locals and cells into a single array.
Saves a pointer in the interpreter and means that we don't need the LOAD_CLOSURE opcode any more
https://bugs.python.org/issue43693
A number of places in the code base (notably ceval.c and frameobject.c) rely on mapping variable names to indices in the frame "locals plus" array (AKA fast locals), and thus opargs. Currently the compiler indirectly encodes that information on the code object as the tuples co_varnames, co_cellvars, and co_freevars. At runtime the dependent code must calculate the proper mapping from those, which isn't ideal and impacts performance-sensitive sections. This is something we can easily address in the compiler instead.
This change addresses the situation by replacing internal use of co_varnames, etc. with a single combined tuple of names in locals-plus order, along with a minimal array mapping each to its kind (local vs. cell vs. free). These two new PyCodeObject fields, co_fastlocalnames and co_fastllocalkinds, are not exposed to Python code for now, but co_varnames, etc. are still available with the same values as before (though computed lazily).
Aside from the (mild) performance impact, there are a number of other benefits:
* there's now a clear, direct relationship between locals-plus and variables
* code that relies on the locals-plus-to-name mapping is simpler
* marshaled code objects are smaller and serialize/de-serialize faster
Also note that we can take this approach further by expanding the possible values in co_fastlocalkinds to include specific argument types (e.g. positional-only, kwargs). Doing so would allow further speed-ups in _PyEval_MakeFrameVector(), which is where args get unpacked into the locals-plus array. It would also allow us to shrink marshaled code objects even further.
https://bugs.python.org/issue43693
* Move up the comment about fields using in hashing/comparision.
* Group the fields more clearly.
* Add co_ncellvars and co_nfreevars.
* Raise ValueError if nlocals != len(varnames), rather than aborting.
* Remove 'zombie' frames. We won't need them once we are allocating fixed-size frames.
* Add co_nlocalplus field to code object to avoid recomputing size of locals + frees + cells.
* Move locals, cells and freevars out of frame object into separate memory buffer.
* Use per-threadstate allocated memory chunks for local variables.
* Move globals and builtins from frame object to per-thread stack.
* Move (slow) locals frame object to per-thread stack.
* Move internal frame functions to internal header.
Guido van Rossum