This makes the Tier 2 interpreter a little faster.
I calculated by about 3%,
though I hesitate to claim an exact number.
This starts by doubling the trace size limit (to 512),
making it more likely that loops fit in a trace.
The rest of the approach is to only load
`oparg` and `operand` in cases that use them.
The code generator know when these are used.
For `oparg`, it will conditionally emit
```
oparg = CURRENT_OPARG();
```
at the top of the case block.
(The `oparg` variable may be referenced multiple times
by the instructions code block, so it must be in a variable.)
For `operand`, it will use `CURRENT_OPERAND()` directly
instead of referencing the `operand` variable,
which no longer exists.
(There is only one place where this will be used.)
- Ensure that `assert(type_version != 0);` always comes *before* using `type_version`
Also:
- In cases_generator, rename `-v` to from `--verbose` to `--viable`
- Double max trace size to 256
- Add a dependency on executor_cases.c.h for ceval.o
- Mark `_SPECIALIZE_UNPACK_SEQUENCE` as `TIER_ONE_ONLY`
- Add debug output back showing the optimized trace
- Bunch of cleanups to Tools/cases_generator/
The "Check if generated files are up to date" job of GitHub Actions
now runs the "autoreconf -ivf -Werror" command instead of the "make
regen-configure" command to avoid depending on the external quay.io
server.
Add Tools/build/regen-configure.sh script to regenerate the configure
with an Ubuntu container image. The
"quay.io/tiran/cpython_autoconf:271" container image
(https://github.com/tiran/cpython_autoconf) is no longer used.
* Replace jumps with deopts in tier 2
* Fewer special cases of uop names
* Add target field to uop IR
* Remove more redundant SET_IP and _CHECK_VALIDITY micro-ops
* Extend whitelist of non-escaping API functions.
The `@critical_section` directive instructs Argument Clinic to generate calls
to `Py_BEGIN_CRITICAL_SECTION()` and `Py_END_CRITICAL_SECTION()` around the
bound function. In `--disable-gil` builds, these calls will lock and unlock
the `self` object. They are no-ops in the default build.
This is used in one place (`_io._Buffered.close`) as a demonstration.
Subsequent PRs will use it more widely in the `_io.Buffered` bindings.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in Argument Clinic (#111585)"
This reverts commit d9b606b3d0.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in getargs.c (#111620)"
This reverts commit cde1071b2a.
* Revert "gh-111089: PyUnicode_AsUTF8() now raises on embedded NUL (#111091)"
This reverts commit d731579bfb.
* Revert "gh-111089: Add PyUnicode_AsUTF8() to the limited C API (#111121)"
This reverts commit d8f32be5b6.
* Revert "gh-111089: Use PyUnicode_AsUTF8() in sqlite3 (#111122)"
This reverts commit 37e4e20eaa.
- There is no longer a separate Python/executor.c file.
- Conventions in Python/bytecodes.c are slightly different -- don't use `goto error`,
you must use `GOTO_ERROR(error)` (same for others like `unused_local_error`).
- The `TIER_ONE` and `TIER_TWO` symbols are only valid in the generated (.c.h) files.
- In Lib/test/support/__init__.py, `Py_C_RECURSION_LIMIT` is imported from `_testcapi`.
- On Windows, in debug mode, stack allocation grows from 8MiB to 12MiB.
- **Beware!** This changes the env vars to enable uops and their debugging
to `PYTHON_UOPS` and `PYTHON_LLTRACE`.
Replace PyUnicode_AsUTF8AndSize() with PyUnicode_AsUTF8() to remove
the explicit check for embedded null characters.
The change avoids to have to include explicitly <string.h> to get the
strlen() function when using a recent version of the limited C API.
* Add mimalloc v2.12
Modified src/alloc.c to remove include of alloc-override.c and not
compile new handler.
Did not include the following files:
- include/mimalloc-new-delete.h
- include/mimalloc-override.h
- src/alloc-override-osx.c
- src/alloc-override.c
- src/static.c
- src/region.c
mimalloc is thread safe and shares a single heap across all runtimes,
therefore finalization and getting global allocated blocks across all
runtimes is different.
* mimalloc: minimal changes for use in Python:
- remove debug spam for freeing large allocations
- use same bytes (0xDD) for freed allocations in CPython and mimalloc
This is important for the test_capi debug memory tests
* Don't export mimalloc symbol in libpython.
* Enable mimalloc as Python allocator option.
* Add mimalloc MIT license.
* Log mimalloc in Lib/test/pythoninfo.py.
* Document new mimalloc support.
* Use macro defs for exports as done in:
https://github.com/python/cpython/pull/31164/
Co-authored-by: Sam Gross <colesbury@gmail.com>
Co-authored-by: Christian Heimes <christian@python.org>
Co-authored-by: Victor Stinner <vstinner@python.org>
Move the following private functions and structures to
pycore_modsupport.h internal C API:
* _PyArg_BadArgument()
* _PyArg_CheckPositional()
* _PyArg_NoKeywords()
* _PyArg_NoPositional()
* _PyArg_ParseStack()
* _PyArg_ParseStackAndKeywords()
* _PyArg_Parser structure
* _PyArg_UnpackKeywords()
* _PyArg_UnpackKeywordsWithVararg()
* _PyArg_UnpackStack()
* _Py_ANY_VARARGS()
Changes:
* Python/getargs.h now includes pycore_modsupport.h to export
functions.
* clinic.py now adds pycore_modsupport.h when one of these functions
is used.
* Add pycore_modsupport.h includes when a C extension uses one of
these functions.
* Define Py_BUILD_CORE_MODULE in C extensions which now include
directly or indirectly (via code generated by Argument Clinic)
pycore_modsupport.h:
* _csv
* _curses_panel
* _dbm
* _gdbm
* _multiprocessing.posixshmem
* _sqlite.row
* _statistics
* grp
* resource
* syslog
* _testcapi: bad_get() no longer uses METH_FASTCALL calling
convention but METH_VARARGS. Replace _PyArg_UnpackStack() with
PyArg_ParseTuple().
* _testcapi: add PYTESTCAPI_NEED_INTERNAL_API macro which is defined
by _testcapi sub-modules which need the internal C API
(pycore_modsupport.h): exceptions.c, float.c, vectorcall.c,
watchers.c.
* Remove Include/cpython/modsupport.h header file.
Include/modsupport.h no longer includes the removed header file.
* Fix mypy clinic.py
* Use explicit initialiser for m_base
* Add module state stub; establish global state on stack
* Put conversion factors in state struct
* Move PyDateTime_TimeZone_UTC to state
* Move PyDateTime_Epoch to state struct
* Fix ref leaks in and clean up initialisation
* The lexer, which include the actual lexeme producing logic, goes into
the `lexer` directory.
* The wrappers, one wrapper per input mode (file, string, utf-8, and
readline), go into the `tokenizer` directory and include logic for
creating a lexer instance and managing the buffer for different modes.
---------
Co-authored-by: Pablo Galindo <pablogsal@gmail.com>
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Fix test_tools.test_freeze on FreeBSD: run "make distclean" instead
of "make clean" in the copied source directory to remove also the
"python" program.
Other test_freeze changes:
* Log executed commands and directories, and the current directory.
* No longer uses make -C option to change the directory, instead use
subprocess cwd parameter.
In Python/bytecodes.c, you now write
```
DEOPT_IF(condition);
```
The code generator expands this to
```
DEOPT_IF(condition, opcode);
```
where `opcode` is the name of the unspecialized instruction.
This works inside macro expansions too.
**CAVEAT:** The entire `DEOPT_IF(condition)` statement must be on a single line.
If it isn't, the substitution will fail; an error will be printed by the code generator
and the C compiler will report some errors.
* _add_python_opts() now handles cross compilation and HOSTRUNNER.
* display_header() now tells if Python is cross-compiled, display
HOSTRUNNER, and get the host platform.
* Remove Tools/scripts/run_tests.py script.
* Remove "make hostrunnertest": use "make buildbottest"
or "make test" instead.
* pycore_pythread.h is now the central place to make sure that
_POSIX_THREADS and _POSIX_SEMAPHORES macros are defined if
available.
* Make sure that pycore_pythread.h is included when _POSIX_THREADS
and _POSIX_SEMAPHORES macros are tested.
* PY_TIMEOUT_MAX is now defined as a constant, since its value
depends on _POSIX_THREADS, instead of being defined as a macro.
* Prevent integer overflow in the preprocessor when computing
PY_TIMEOUT_MAX_VALUE on Windows:
replace "0xFFFFFFFELL * 1000 < LLONG_MAX"
with "0xFFFFFFFELL < LLONG_MAX / 1000".
* Document the change and give hints how to fix affected code.
* Add an exception for PY_TIMEOUT_MAX name to smelly.py
* Add PY_TIMEOUT_MAX to the stable ABI
These are the most popular specializations of `LOAD_ATTR` and `STORE_ATTR`
that weren't already viable uops:
* Split LOAD_ATTR_METHOD_WITH_VALUES
* Split LOAD_ATTR_METHOD_NO_DICT
* Split LOAD_ATTR_SLOT
* Split STORE_ATTR_SLOT
* Split STORE_ATTR_INSTANCE_VALUE
Also:
* Add `-v` flag to code generator which prints a list of non-viable uops
(easter-egg: it can print execution counts -- see source)
* Double _Py_UOP_MAX_TRACE_LENGTH to 128
I had dropped one of the DEOPT_IF() calls! :-(
Fix the test when run on an installed Python: use "abs_srcdir" of
sysconfig, and skip the test if the Python source code cannot be
found.
* Tools/patchcheck/patchcheck.py, Tools/freeze/test/freeze.py and
Lib/test/libregrtest/utils.py now first try to get "abs_srcdir"
from sysconfig, before getting "srcdir" from sysconfig.
* test.pythoninfo logs sysconfig "abs_srcdir".
Fix copy_source_tree() function of test_tools.test_freeze:
* Don't copy SRC_DIR/build/ anymore. This directory is modified by
other tests running in parallel.
* Add test.support.copy_python_src_ignore().
* Use sysconfig to get the source directory.
* Use sysconfig.get_config_var() to get CONFIG_ARGS variable.
When --fast-ci or --slow-ci option is used, regrtest now replaces the
current process with a new process to add "-u -W default -bb -E"
options to Python.
Changes:
* PCbuild/rt.bat and Tools/scripts/run_tests.py no longer need to add
"-u -W default -bb -E" options to Python: it's now done by
regrtest.
* Fix Tools/scripts/run_tests.py: flush stdout before replacing the
process. Previously, buffered messages were lost.
* Add --fast-ci and --slow-ci options to libregrtest:
* --fast-ci uses a default timeout of 10 minutes and "-u all,-cpu"
(skip slowest tests).
* --slow-ci uses a default timeout of 20 minues and "-u all" (run
all tests).
* regrtest header now lists test resources.
* Makefile changes:
* "make test", "make hostrunnertest" and "make coverage-report" now
use --fast-ci option and TESTTIMEOUT variable.
* "make buildbottest" now uses "--slow-ci". Remove options which
became redundant with "--slow-ci".
* "make testall" and "make testuniversal" now use --slow-ci option
and TESTTIMEOUT variable.
* "make testall" now uses "find -exec rm ..." instead of
"find ... -print|xargs rm ...", same as "make clean".
* GitHub Actions workflow:
* Ubuntu and Address Sanitizer jobs now use "make test". Remove
options which became redundant with "--fast-ci".
* Windows jobs now use --fast-ci option.
* Use -j0 to detect the number of CPUs.
* Set Makefile TESTTIMEOUT default to an empty string, since
--slow-ci and --fast-ci use different default timeout. It's now
accepted to pass "--timeout=" to regrtest: treated as not timeout.
* Tools/scripts/run_tests.py now uses --fast-ci option.
* Tools/buildbot/test.bat now uses --slow-ci option. Remove
--timeout=1200 option, redundant with --slow-ci.
Make sure that the internal C API is not tested by mistake by
_testcapi.
Undefine Py_BUILD_CORE_BUILTIN and Py_BUILD_CORE_MODULE macros in
Modules/_testcapi/parts.h: move code from _testcapimodule.c.
heaptype_relative.c and vectorcall_limited.c are using the limited C
API which is incompatible with the internal C API.
Move test_long_numbits() from _testcapi to _testinternalcapi since it
uses the internal C API "pycore_long.h".
Fix Modules/_testcapi/pyatomic.c: don't include Python.h directly,
just include _testcapi/parts.h.
Ajust "make check-c-globals" for these changes.
PyMutex is a one byte lock with fast, inlineable lock and unlock functions for the common uncontended case. The design is based on WebKit's WTF::Lock.
PyMutex is built using the _PyParkingLot APIs, which provides a cross-platform futex-like API (based on WebKit's WTF::ParkingLot). This internal API will be used for building other synchronization primitives used to implement PEP 703, such as one-time initialization and events.
This also includes tests and a mini benchmark in Tools/lockbench/lockbench.py to compare with the existing PyThread_type_lock.
Uncontended acquisition + release:
* Linux (x86-64): PyMutex: 11 ns, PyThread_type_lock: 44 ns
* macOS (arm64): PyMutex: 13 ns, PyThread_type_lock: 18 ns
* Windows (x86-64): PyMutex: 13 ns, PyThread_type_lock: 38 ns
PR Overview:
The primary purpose of this PR is to implement PyMutex, but there are a number of support pieces (described below).
* PyMutex: A 1-byte lock that doesn't require memory allocation to initialize and is generally faster than the existing PyThread_type_lock. The API is internal only for now.
* _PyParking_Lot: A futex-like API based on the API of the same name in WebKit. Used to implement PyMutex.
* _PyRawMutex: A word sized lock used to implement _PyParking_Lot.
* PyEvent: A one time event. This was used a bunch in the "nogil" fork and is useful for testing the PyMutex implementation, so I've included it as part of the PR.
* pycore_llist.h: Defines common operations on doubly-linked list. Not strictly necessary (could do the list operations manually), but they come up frequently in the "nogil" fork. ( Similar to https://man.freebsd.org/cgi/man.cgi?queue)
---------
Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>
This makes the internal representation in the code generator simpler: there's a list of ops, and a list of macros, and there's no special-casing needed for ops that aren't macros. (There's now special-casing for ops that are also macros, but that's simpler.)
Builtin functions and methods that have non-representable signatures today
will have representable signatures yesterday, and they will become unusable
for testing this feature.
So we need to add special functions and methods to the _testcapi module
that always have non-representable signatures.
I must have overlooked this when refactoring the code generator.
The Tier 1 interpreter contained a few silly things like
```
goto resume_frame;
STACK_SHRINK(1);
```
(and other variations, some where the unconditional `goto` was hidden in a macro).
* Rename SAVE_IP to _SET_IP
* Rename EXIT_TRACE to _EXIT_TRACE
* Rename SAVE_CURRENT_IP to _SAVE_CURRENT_IP
* Rename INSERT to _INSERT (This is for Ken Jin's abstract interpreter)
* Rename IS_NONE to _IS_NONE
* Rename JUMP_TO_TOP to _JUMP_TO_TOP
This adds a 16-bit inline cache entry to the conditional branch instructions POP_JUMP_IF_{FALSE,TRUE,NONE,NOT_NONE} and their instrumented variants, which is used to keep track of the branch direction.
Each time we encounter these instructions we shift the cache entry left by one and set the bottom bit to whether we jumped.
Then when it's time to translate such a branch to Tier 2 uops, we use the bit count from the cache entry to decided whether to continue translating the "didn't jump" branch or the "jumped" branch.
The counter is initialized to a pattern of alternating ones and zeros to avoid bias.
The .pyc file magic number is updated. There's a new test, some fixes for existing tests, and a few miscellaneous cleanups.
Fix a race condition in "make regen-all". The deepfreeze.c source and
files generated by Argument Clinic are now generated or updated
before generating "global objects". Previously, some identifiers may
miss depending on the order in which these files were generated.
* "make regen-global-objects": Make sure that deepfreeze.c is
generated and up to date, and always run "make clinic".
* "make clinic" no longer runs generate_global_objects.py script.
* "make regen-deepfreeze" now only updates deepfreeze.c (C file).
It doesn't build deepfreeze.o (object) anymore.
* Remove misleading messages in "make regen-global-objects" and
"make clinic". They are now outdated, these commands are now
safe to use.
* Document generates files in Doc/using/configure.rst.
Co-authored-by: Erlend E. Aasland <erlend@python.org>
Output with one wheel:
```
❯ GITHUB_ACTIONS=true ./Tools/build/verify_ensurepip_wheels.py
Verifying checksum for /Volumes/RAMDisk/cpython/Lib/ensurepip/_bundled/pip-23.2.1-py3-none-any.whl.
Expected digest: 7ccf472345f20d35bdc9d1841ff5f313260c2c33fe417f48c30ac46cccabf5be
Actual digest: 7ccf472345f20d35bdc9d1841ff5f313260c2c33fe417f48c30ac46cccabf5be
::notice file=/Volumes/RAMDisk/cpython/Lib/ensurepip/_bundled/pip-23.2.1-py3-none-any.whl::Successfully verified the checksum of the pip wheel.
```
Output with two wheels:
```
❯ GITHUB_ACTIONS=true ./Tools/build/verify_ensurepip_wheels.py
::error file=/Volumes/RAMDisk/cpython/Lib/ensurepip/_bundled/pip-22.0.4-py3-none-any.whl::Found more than one wheel for package pip.
::error file=/Volumes/RAMDisk/cpython/Lib/ensurepip/_bundled/pip-23.2.1-py3-none-any.whl::Found more than one wheel for package pip.
```
Output without wheels:
```
❯ GITHUB_ACTIONS=true ./Tools/build/verify_ensurepip_wheels.py
::error file=::Could not find a pip wheel on disk.
```
Argument Clinic now only includes pycore_gc.h if PyGC_Head is needed,
and only includes pycore_runtime.h if _Py_ID() is needed.
* Add 'condition' optional argument to Clinic.add_include().
* deprecate_keyword_use() includes pycore_runtime.h when using
the _PyID() function.
* Fix rendering of includes: comments start at the column 35.
* Mark PC/clinic/_wmimodule.cpp.h and
"Objects/stringlib/clinic/*.h.h" header files as generated in
.gitattributes.
Effects:
* 42 header files generated by AC no longer include the internal C
API, instead of 4 header files before. For example,
Modules/clinic/_abc.c.h no longer includes the internal C API.
* Fix _testclinic_depr.c.h: it now always includes pycore_runtime.h
to get _Py_ID().
Also remove NOP instructions.
The "stubs" are not optimized in this fashion (their SAVE_IP should always be preserved since it's where to jump next, and they don't contain NOPs by their nature).
Move these private functions to the internal C API
(pycore_abstract.h):
* _Py_convert_optional_to_ssize_t()
* _PyNumber_Index()
Argument Clinic now emits #include "pycore_abstract.h" when these
functions are used.
The parser of the c-analyzer tool now uses a list of files which use
the limited C API, rather than a list of files using the internal C
API.
Move the private _PyLong converter functions to the internal C API
* _PyLong_FileDescriptor_Converter(): moved to pycore_fileutils.h
* _PyLong_Size_t_Converter(): moved to pycore_long.h
Argument Clinic now emits includes for pycore_fileutils.h and
pycore_long.h when these functions are used.
Move these private functions to the internal C API (pycore_long.h):
* _PyLong_UnsignedInt_Converter()
* _PyLong_UnsignedLongLong_Converter()
* _PyLong_UnsignedLong_Converter()
* _PyLong_UnsignedShort_Converter()
Argument Clinic now emits #include "pycore_long.h" when these
functions are used.
* Add Clinic.add_include() method
* Add CConverter.include and CConverter.add_include()
* Printer.print_block() gets a second parameter: clinic.
* Remove duplicated declaration of "clinic" global variable.
Argument Clinic now has a partial support of the
Limited API:
* Add --limited option to clinic.c.
* Add '_testclinic_limited' extension which is built with
the limited C API version 3.13.
* For now, hardcode in clinic.py that "_testclinic_limited.c" targets
the limited C API.
Instead of using `GO_TO_INSTRUCTION(CALL_PY_EXACT_ARGS)` we just add the macro elements of the latter to the macro for the former. This requires lengthening the uops array in struct opcode_macro_expansion. (It also required changes to stacking.py that were merged already.)
I was comparing the last preceding poke with the *last* peek,
rather than the *first* peek.
Unfortunately this bug obscured another bug:
When the last preceding poke is UNUSED, the first peek disappears,
leaving the variable unassigned. This is how I fixed it:
- Rename CopyEffect to CopyItem.
- Change CopyItem to contain StackItems instead of StackEffects.
- Update those StackItems when adjusting the manager higher or lower.
- Assert that those StackItems' offsets are equivalent.
- Other clever things.
---------
Co-authored-by: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>
No longer export _PyUnicode_FromId() internal C API function.
Change comment style to "// comment" and add comment explaining why
other functions have to be exported.
Update Tools/build/generate_token.py to update Include/internal/pycore_token.h
comments.
* Add missing includes.
* Remove unused includes.
* Update old include/symbol names to newer names.
* Mention at least one included symbol.
* Sort includes.
* Update Tools/cases_generator/generate_cases.py used to generated
pycore_opcode_metadata.h.
* Update Parser/asdl_c.py used to generate pycore_ast.h.
* Cleanup also includes in _testcapimodule.c and _testinternalcapi.c.
* pycore_intrinsics.h does nothing if included twice
(add #ifndef and #define).
* Update Tools/cases_generator/generate_cases.py to generate the
Py_BUILD_CORE test.
* _bz2, _lzma, _opcode and zlib extensions now define the
Py_BUILD_CORE_MODULE macro to use internal headers
(pycore_code.h, pycore_intrinsics.h and pycore_blocks_output_buffer.h).
It is now possible to deprecate passing keyword arguments for
keyword-or-positional parameters with Argument Clinic, using the new
'/ [from X.Y]' syntax.
(To be read as "positional-only from Python version X.Y")
Co-authored-by: Erlend E. Aasland <erlend@python.org>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
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.
'not hasattr(parent, "classes")' is always false, since 'parent' is an
instance of either the Module, Class, or Clinic classes, and all of
them has a "classes" attribute.
* Split `CALL_PY_EXACT_ARGS` into uops
This is only the first step for doing `CALL` in Tier 2.
The next step involves tracing into the called code object and back.
After that we'll have to do the remaining `CALL` specialization.
Finally we'll have to deal with `KW_NAMES`.
Note: this moves setting `frame->return_offset` directly in front of
`DISPATCH_INLINED()`, to make it easier to move it into `_PUSH_FRAME`.
* Instead of calling get_identifiers_and_strings(), extract identifiers and strings from pycore_global_strings.h.
* Avoid ast.literal_eval(), it's very slow.
Move the "deprecated positinal" tests from clinic.test.c to
_testclinic.c. Mock PY_VERSION_HEX in order to prevent generated
compiler warnings/errors to trigger. Put clinic code for deprecated
positionals in Modules/clinic/_testclinic_depr_star.c.h for easy
inspection of the generated code.
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Extract helper methods for formatting the signature and parameter
sections, and clean up the remaining function body.
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
- Generalize the syntax for the type of a stack effect to allow a trailing `*`,
so we can declare something as e.g. `PyCodeObject *`.
- When generating assignments for stack effects,
the type of the value on the stack should be the default (i.e., `PyObject *`)
even when the variable copied to/from it has a different type,
so that an appropriate cast is generated
However, not when the variable is an array --
then the type is taken from the variable (as it is always `PyObject **`).
It is now possible to deprecate passing parameters positionally with
Argument Clinic, using the new '* [from X.Y]' syntax.
(To be read as "keyword-only from Python version X.Y")
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
This fixes two tiny defects in analysis.py that I didn't catch on time in #107564:
- `get_var_names` in `check_macro_consistency` should skip `UNUSED` names.
- Fix an occurrence of `is UNUSED` (should be `==`).
Introducing a new file, stacking.py, that takes over several responsibilities related to symbolic evaluation of push/pop operations, with more generality.
- always wrap the offending line, token, or name in quotes
- in most cases, put the entire error message on one line
Added tests for uncovered branches that were touched by this PR.
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>