* Suspend Python threads before fork()
Add stop-the-world thread suspension around fork() to prevent
deadlocks from locks held by dead parent threads in the child.
- Thread states: DETACHED / ATTACHED / SUSPENDED with atomic CAS
transitions matching _PyThreadState_{Attach,Detach,Suspend}
- stop_the_world / start_the_world: park all non-requester threads
before fork, resume after (parent) or reset (child)
- allow_threads (Py_BEGIN/END_ALLOW_THREADS): detach around blocking
syscalls (os.read/write, waitpid, Lock.acquire, time.sleep) so
stop_the_world can force-park via CAS
- Acquire/release import lock around fork lifecycle
- zero_reinit_after_fork: generic lock reset for parking_lot types
- gc_clear_raw: detach dict instead of clearing entries
- Lock-free double-check for descriptor cache reads (no read-side
seqlock); write-side seqlock retained for writer serialization
- fork() returns PyResult, checks PythonFinalizationError, calls
sys.audit
4096-entry direct-mapped cache keyed by (tp_version_tag, interned_name_ptr)
using lock-free SeqLock pattern for concurrent access.
- find_name_in_mro() checks cache before MRO walk
- has_name_in_mro() avoids cloning on cache hit
- Auto-assigns version tags on cache miss
- Invalidation via modified() (tp_version_tag=0) with value drops
- TYPE_CACHE_CLEARING flag suppresses re-population during GC drops
- Clear method cache during GC collection to break reference cycles
* Implement LOAD_ATTR inline caching with adaptive specialization
Add type version counter (tp_version_tag) to PyType with subclass
invalidation cascade. Add cache read/write methods (u16/u32/u64)
to CodeUnits. Implement adaptive specialization in load_attr that
replaces the opcode with specialized variants on first execution:
- LoadAttrMethodNoDict: cached method lookup for slotted types
- LoadAttrMethodWithValues: cached method with dict shadow check
- LoadAttrInstanceValue: direct dict lookup skipping descriptors
Specialized opcodes guard on type_version_tag and deoptimize back
to generic LOAD_ATTR with backoff counter on cache miss.
* Add BINARY_OP and CALL adaptive specialization
BINARY_OP: Specialize int add/subtract/multiply and float
add/subtract/multiply with type guards and deoptimization.
CALL: Add func_version to PyFunction, specialize simple
function calls (CallPyExactArgs, CallBoundMethodExactArgs)
with invoke_exact_args fast path that skips FuncArgs
allocation and fill_locals_from_args.
* Lazy quickening for adaptive specialization counters
Move counter initialization from compile-time to RESUME execution,
matching CPython's _PyCode_Quicken pattern. Store counter in CACHE
entry's arg byte to preserve op=Instruction::Cache for dis/JIT.
Add PyCode.quickened flag for one-time initialization.
* Add Instruction::deoptimize() and CodeUnits::original_bytes()
- deoptimize() maps specialized opcodes back to their base adaptive variant
- original_bytes() produces deoptimized bytecode with zeroed CACHE entries
- co_code now returns deoptimized bytes, _co_code_adaptive returns current bytes
- Marshal serialization uses original_bytes() instead of raw transmute
* Fix monitoring and specialization interaction
- cache_entries() returns correct count for instrumented opcodes
- deoptimize() maps instrumented opcodes back to base
- quicken() skips adaptive counter for instrumented opcodes
- instrument_code Phase 3 deoptimizes specialized opcodes and
clears CACHE entries to prevent stale pointer dereferences
* Address review: bounds checks, UB fix, version overflow, error handling
- Add bounds checks to read_cache_u16/u32/u64
- Fix quicken() aliasing UB by using &mut directly
- Add JumpBackwardJit/JumpBackwardNoJit to deoptimize()
- Guard can_specialize_call with NEWLOCALS flag check
- Use compare_exchange_weak for version tag to prevent wraparound
- Propagate dict lookup errors in LoadAttrMethodWithValues
- Apply adaptive backoff on version tag assignment failure
- Remove duplicate imports in frame.rs
* Add missing _winapi functions and fix WinHandle int conversion
Add 13 functions: ReadFile, SetNamedPipeHandleState, CreateFileMapping,
OpenFileMapping, MapViewOfFile, UnmapViewOfFile, VirtualQuerySize,
CopyFile2, ResetEvent, CreateMutex, OpenEventW, LoadLibrary,
_mimetypes_read_windows_registry.
Add constants: INVALID_HANDLE_VALUE, FILE_MAP_READ/WRITE/COPY/EXECUTE.
Change WinHandle integer type from usize to isize so negative values
like INVALID_HANDLE_VALUE (-1) can be passed from Python.
* Align _winapi module with CPython
- Rename winapi.rs to _winapi.rs with #[path] attribute
- Rename CreateMutex to CreateMutexW
- Add missing constants: ERROR_ACCESS_DENIED, ERROR_PRIVILEGE_NOT_HELD,
PROCESS_ALL_ACCESS, 10 STARTF_ constants, LOCALE_NAME_SYSTEM_DEFAULT,
LOCALE_NAME_USER_DEFAULT, COPY_FILE_DIRECTORY
- Fix OpenMutexW return type and ReleaseMutex param type to use WinHandle
* Fix ReadFile/WriteFile overlapped keyword argument
Use FromArgs structs so overlapped parameter can be passed as
a keyword argument (overlapped=True), matching the CPython API.
* Remove extra constants and LoadLibrary not in CPython _winapi
Remove 19 constants (WAIT_ABANDONED, CREATE_ALWAYS, CREATE_NEW,
OPEN_ALWAYS, TRUNCATE_EXISTING, FILE_ATTRIBUTE_NORMAL, 8 FILE_FLAG_*,
3 FILE_SHARE_*, NMPWAIT_NOWAIT, NMPWAIT_USE_DEFAULT_WAIT) and
LoadLibrary function that are not present in CPython's _winapi module.
* Fix utf8_mode default to 0 and add PYTHONUTF8 env var support
Default utf8_mode was incorrectly set to 1, causing text-mode
subprocess to always decode as UTF-8 instead of locale encoding.
Changed default to 0 to match CPython 3.13 behavior on Windows.
Added PYTHONUTF8 environment variable handling with -X utf8 override.
* Fix CopyFile2 to raise proper OSError subclass
Use std::io::Error::from_raw_os_error instead of vm.new_os_error so
that winerror attribute is set and errno-to-exception mapping works
(e.g. ERROR_ACCESS_DENIED → PermissionError).
* Fix syntax_non_utf8 test to not depend on locale encoding
Use explicit encoding='latin-1' so the test works regardless of
the system locale (e.g. C/POSIX locale uses ASCII by default).
- TypeVar/ParamSpec repr: use infer_variance flag
- ParamSpec: add type_check on bound argument
- ParamSpecArgs/Kwargs: use equality instead of identity
- NoDefault: change to IMMUTABLETYPE flag
- subscript_generic: wrap TypeVarTuple in Unpack
- symboltable: selective name mangling in type param scopes
- symboltable: fix double default scanning for non-generic fns
- Unmark 4 passing tests in test_type_params
* Add host_env feature for sandbox isolation
Introduce a `host_env` feature flag that gates all host environment
access (filesystem, network, signals, processes). When disabled,
the VM operates in sandbox mode:
- _io module always available; FileIO gated by host_env
- SandboxStdio provides lightweight stdin/stdout/stderr via Rust std::io
- BytesIO/StringIO/BufferedIO/TextIOWrapper work without host_env
- open() returns UnsupportedOperation in sandbox
- stdlib modules (os, socket, signal, etc.) gated by host_env
- CI checks both host_env ON and OFF builds
* Auto-format: ruff check --select I --fix
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Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Jeong, YunWon