cpython/Include/internal/pycore_ceval.h
Ken Jin 22b0de2755
gh-117139: Convert the evaluation stack to stack refs (#118450)
This PR sets up tagged pointers for CPython.

The general idea is to create a separate struct _PyStackRef for everything on the evaluation stack to store the bits. This forces the C compiler to warn us if we try to cast things or pull things out of the struct directly.

Only for free threading: We tag the low bit if something is deferred - that means we skip incref and decref operations on it. This behavior may change in the future if Mark's plans to defer all objects in the interpreter loop pans out.

This implies a strict stack reference discipline is required. ALL incref and decref operations on stackrefs must use the stackref variants. It is unsafe to untag something then do normal incref/decref ops on it.

The new incref and decref variants are called dup and close. They mimic a "handle" API operating on these stackrefs.

Please read Include/internal/pycore_stackref.h for more information!

---------

Co-authored-by: Mark Shannon <9448417+markshannon@users.noreply.github.com>
2024-06-27 03:10:43 +08:00

313 lines
11 KiB
C

#ifndef Py_INTERNAL_CEVAL_H
#define Py_INTERNAL_CEVAL_H
#ifdef __cplusplus
extern "C" {
#endif
#ifndef Py_BUILD_CORE
# error "this header requires Py_BUILD_CORE define"
#endif
#include "dynamic_annotations.h" // _Py_ANNOTATE_RWLOCK_CREATE
#include "pycore_interp.h" // PyInterpreterState.eval_frame
#include "pycore_pystate.h" // _PyThreadState_GET()
/* Forward declarations */
struct pyruntimestate;
struct _ceval_runtime_state;
// Export for '_lsprof' shared extension
PyAPI_FUNC(int) _PyEval_SetProfile(PyThreadState *tstate, Py_tracefunc func, PyObject *arg);
extern int _PyEval_SetTrace(PyThreadState *tstate, Py_tracefunc func, PyObject *arg);
extern int _PyEval_SetOpcodeTrace(PyFrameObject *f, bool enable);
// Helper to look up a builtin object
// Export for 'array' shared extension
PyAPI_FUNC(PyObject*) _PyEval_GetBuiltin(PyObject *);
extern PyObject* _PyEval_GetBuiltinId(_Py_Identifier *);
extern void _PyEval_SetSwitchInterval(unsigned long microseconds);
extern unsigned long _PyEval_GetSwitchInterval(void);
// Export for '_queue' shared extension
PyAPI_FUNC(int) _PyEval_MakePendingCalls(PyThreadState *);
#ifndef Py_DEFAULT_RECURSION_LIMIT
# define Py_DEFAULT_RECURSION_LIMIT 1000
#endif
extern void _Py_FinishPendingCalls(PyThreadState *tstate);
extern void _PyEval_InitState(PyInterpreterState *);
extern void _PyEval_SignalReceived(void);
// bitwise flags:
#define _Py_PENDING_MAINTHREADONLY 1
#define _Py_PENDING_RAWFREE 2
typedef int _Py_add_pending_call_result;
#define _Py_ADD_PENDING_SUCCESS 0
#define _Py_ADD_PENDING_FULL -1
// Export for '_testinternalcapi' shared extension
PyAPI_FUNC(_Py_add_pending_call_result) _PyEval_AddPendingCall(
PyInterpreterState *interp,
_Py_pending_call_func func,
void *arg,
int flags);
#ifdef HAVE_FORK
extern PyStatus _PyEval_ReInitThreads(PyThreadState *tstate);
#endif
// Used by sys.call_tracing()
extern PyObject* _PyEval_CallTracing(PyObject *func, PyObject *args);
// Used by sys.get_asyncgen_hooks()
extern PyObject* _PyEval_GetAsyncGenFirstiter(void);
extern PyObject* _PyEval_GetAsyncGenFinalizer(void);
// Used by sys.set_asyncgen_hooks()
extern int _PyEval_SetAsyncGenFirstiter(PyObject *);
extern int _PyEval_SetAsyncGenFinalizer(PyObject *);
// Used by sys.get_coroutine_origin_tracking_depth()
// and sys.set_coroutine_origin_tracking_depth()
extern int _PyEval_GetCoroutineOriginTrackingDepth(void);
extern int _PyEval_SetCoroutineOriginTrackingDepth(int depth);
extern void _PyEval_Fini(void);
extern PyObject* _PyEval_GetBuiltins(PyThreadState *tstate);
extern PyObject* _PyEval_BuiltinsFromGlobals(
PyThreadState *tstate,
PyObject *globals);
// Trampoline API
typedef struct {
// Callback to initialize the trampoline state
void* (*init_state)(void);
// Callback to register every trampoline being created
void (*write_state)(void* state, const void *code_addr,
unsigned int code_size, PyCodeObject* code);
// Callback to free the trampoline state
int (*free_state)(void* state);
} _PyPerf_Callbacks;
extern int _PyPerfTrampoline_SetCallbacks(_PyPerf_Callbacks *);
extern void _PyPerfTrampoline_GetCallbacks(_PyPerf_Callbacks *);
extern int _PyPerfTrampoline_Init(int activate);
extern int _PyPerfTrampoline_Fini(void);
extern void _PyPerfTrampoline_FreeArenas(void);
extern int _PyIsPerfTrampolineActive(void);
extern PyStatus _PyPerfTrampoline_AfterFork_Child(void);
#ifdef PY_HAVE_PERF_TRAMPOLINE
extern _PyPerf_Callbacks _Py_perfmap_callbacks;
extern _PyPerf_Callbacks _Py_perfmap_jit_callbacks;
#endif
static inline PyObject*
_PyEval_EvalFrame(PyThreadState *tstate, struct _PyInterpreterFrame *frame, int throwflag)
{
EVAL_CALL_STAT_INC(EVAL_CALL_TOTAL);
if (tstate->interp->eval_frame == NULL) {
return _PyEval_EvalFrameDefault(tstate, frame, throwflag);
}
return tstate->interp->eval_frame(tstate, frame, throwflag);
}
extern PyObject*
_PyEval_Vector(PyThreadState *tstate,
PyFunctionObject *func, PyObject *locals,
PyObject* const* args, size_t argcount,
PyObject *kwnames);
extern int _PyEval_ThreadsInitialized(void);
extern void _PyEval_InitGIL(PyThreadState *tstate, int own_gil);
extern void _PyEval_FiniGIL(PyInterpreterState *interp);
extern void _PyEval_AcquireLock(PyThreadState *tstate);
extern void _PyEval_ReleaseLock(PyInterpreterState *, PyThreadState *,
int final_release);
#ifdef Py_GIL_DISABLED
// Returns 0 or 1 if the GIL for the given thread's interpreter is disabled or
// enabled, respectively.
//
// The enabled state of the GIL will not change while one or more threads are
// attached.
static inline int
_PyEval_IsGILEnabled(PyThreadState *tstate)
{
struct _gil_runtime_state *gil = tstate->interp->ceval.gil;
return _Py_atomic_load_int_relaxed(&gil->enabled) != 0;
}
// Enable or disable the GIL used by the interpreter that owns tstate, which
// must be the current thread. This may affect other interpreters, if the GIL
// is shared. All three functions will be no-ops (and return 0) if the
// interpreter's `enable_gil' config is not _PyConfig_GIL_DEFAULT.
//
// Every call to _PyEval_EnableGILTransient() must be paired with exactly one
// call to either _PyEval_EnableGILPermanent() or
// _PyEval_DisableGIL(). _PyEval_EnableGILPermanent() and _PyEval_DisableGIL()
// must only be called while the GIL is enabled from a call to
// _PyEval_EnableGILTransient().
//
// _PyEval_EnableGILTransient() returns 1 if it enabled the GIL, or 0 if the
// GIL was already enabled, whether transiently or permanently. The caller will
// hold the GIL upon return.
//
// _PyEval_EnableGILPermanent() returns 1 if it permanently enabled the GIL
// (which must already be enabled), or 0 if it was already permanently
// enabled. Once _PyEval_EnableGILPermanent() has been called once, all
// subsequent calls to any of the three functions will be no-ops.
//
// _PyEval_DisableGIL() returns 1 if it disabled the GIL, or 0 if the GIL was
// kept enabled because of another request, whether transient or permanent.
//
// All three functions must be called by an attached thread (this implies that
// if the GIL is enabled, the current thread must hold it).
extern int _PyEval_EnableGILTransient(PyThreadState *tstate);
extern int _PyEval_EnableGILPermanent(PyThreadState *tstate);
extern int _PyEval_DisableGIL(PyThreadState *state);
#endif
extern void _PyEval_DeactivateOpCache(void);
/* --- _Py_EnterRecursiveCall() ----------------------------------------- */
#ifdef USE_STACKCHECK
/* With USE_STACKCHECK macro defined, trigger stack checks in
_Py_CheckRecursiveCall() on every 64th call to _Py_EnterRecursiveCall. */
static inline int _Py_MakeRecCheck(PyThreadState *tstate) {
return (tstate->c_recursion_remaining-- < 0
|| (tstate->c_recursion_remaining & 63) == 0);
}
#else
static inline int _Py_MakeRecCheck(PyThreadState *tstate) {
return tstate->c_recursion_remaining-- < 0;
}
#endif
// Export for '_json' shared extension, used via _Py_EnterRecursiveCall()
// static inline function.
PyAPI_FUNC(int) _Py_CheckRecursiveCall(
PyThreadState *tstate,
const char *where);
int _Py_CheckRecursiveCallPy(
PyThreadState *tstate);
static inline int _Py_EnterRecursiveCallTstate(PyThreadState *tstate,
const char *where) {
return (_Py_MakeRecCheck(tstate) && _Py_CheckRecursiveCall(tstate, where));
}
static inline void _Py_EnterRecursiveCallTstateUnchecked(PyThreadState *tstate) {
assert(tstate->c_recursion_remaining > 0);
tstate->c_recursion_remaining--;
}
static inline int _Py_EnterRecursiveCall(const char *where) {
PyThreadState *tstate = _PyThreadState_GET();
return _Py_EnterRecursiveCallTstate(tstate, where);
}
static inline void _Py_LeaveRecursiveCallTstate(PyThreadState *tstate) {
tstate->c_recursion_remaining++;
}
static inline void _Py_LeaveRecursiveCall(void) {
PyThreadState *tstate = _PyThreadState_GET();
_Py_LeaveRecursiveCallTstate(tstate);
}
extern struct _PyInterpreterFrame* _PyEval_GetFrame(void);
PyAPI_FUNC(PyObject *)_Py_MakeCoro(PyFunctionObject *func);
/* Handle signals, pending calls, GIL drop request
and asynchronous exception */
PyAPI_FUNC(int) _Py_HandlePending(PyThreadState *tstate);
extern PyObject * _PyEval_GetFrameLocals(void);
typedef PyObject *(*conversion_func)(PyObject *);
PyAPI_DATA(const binaryfunc) _PyEval_BinaryOps[];
PyAPI_DATA(const conversion_func) _PyEval_ConversionFuncs[];
typedef struct _special_method {
PyObject *name;
const char *error;
} _Py_SpecialMethod;
PyAPI_DATA(const _Py_SpecialMethod) _Py_SpecialMethods[];
PyAPI_FUNC(int) _PyEval_CheckExceptStarTypeValid(PyThreadState *tstate, PyObject* right);
PyAPI_FUNC(int) _PyEval_CheckExceptTypeValid(PyThreadState *tstate, PyObject* right);
PyAPI_FUNC(int) _PyEval_ExceptionGroupMatch(PyObject* exc_value, PyObject *match_type, PyObject **match, PyObject **rest);
PyAPI_FUNC(void) _PyEval_FormatAwaitableError(PyThreadState *tstate, PyTypeObject *type, int oparg);
PyAPI_FUNC(void) _PyEval_FormatExcCheckArg(PyThreadState *tstate, PyObject *exc, const char *format_str, PyObject *obj);
PyAPI_FUNC(void) _PyEval_FormatExcUnbound(PyThreadState *tstate, PyCodeObject *co, int oparg);
PyAPI_FUNC(void) _PyEval_FormatKwargsError(PyThreadState *tstate, PyObject *func, PyObject *kwargs);
PyAPI_FUNC(PyObject *)_PyEval_MatchClass(PyThreadState *tstate, PyObject *subject, PyObject *type, Py_ssize_t nargs, PyObject *kwargs);
PyAPI_FUNC(PyObject *)_PyEval_MatchKeys(PyThreadState *tstate, PyObject *map, PyObject *keys);
PyAPI_FUNC(int) _PyEval_UnpackIterableStackRef(PyThreadState *tstate, _PyStackRef v, int argcnt, int argcntafter, _PyStackRef *sp);
PyAPI_FUNC(void) _PyEval_FrameClearAndPop(PyThreadState *tstate, _PyInterpreterFrame *frame);
PyAPI_FUNC(PyObject **) _PyObjectArray_FromStackRefArray(_PyStackRef *input, Py_ssize_t nargs, PyObject **scratch);
PyAPI_FUNC(void) _PyObjectArray_Free(PyObject **array, PyObject **scratch);
/* Bits that can be set in PyThreadState.eval_breaker */
#define _PY_GIL_DROP_REQUEST_BIT (1U << 0)
#define _PY_SIGNALS_PENDING_BIT (1U << 1)
#define _PY_CALLS_TO_DO_BIT (1U << 2)
#define _PY_ASYNC_EXCEPTION_BIT (1U << 3)
#define _PY_GC_SCHEDULED_BIT (1U << 4)
#define _PY_EVAL_PLEASE_STOP_BIT (1U << 5)
#define _PY_EVAL_EXPLICIT_MERGE_BIT (1U << 6)
/* Reserve a few bits for future use */
#define _PY_EVAL_EVENTS_BITS 8
#define _PY_EVAL_EVENTS_MASK ((1 << _PY_EVAL_EVENTS_BITS)-1)
static inline void
_Py_set_eval_breaker_bit(PyThreadState *tstate, uintptr_t bit)
{
_Py_atomic_or_uintptr(&tstate->eval_breaker, bit);
}
static inline void
_Py_unset_eval_breaker_bit(PyThreadState *tstate, uintptr_t bit)
{
_Py_atomic_and_uintptr(&tstate->eval_breaker, ~bit);
}
static inline int
_Py_eval_breaker_bit_is_set(PyThreadState *tstate, uintptr_t bit)
{
uintptr_t b = _Py_atomic_load_uintptr_relaxed(&tstate->eval_breaker);
return (b & bit) != 0;
}
// Free-threaded builds use these functions to set or unset a bit on all
// threads in the given interpreter.
void _Py_set_eval_breaker_bit_all(PyInterpreterState *interp, uintptr_t bit);
void _Py_unset_eval_breaker_bit_all(PyInterpreterState *interp, uintptr_t bit);
#ifdef __cplusplus
}
#endif
#endif /* !Py_INTERNAL_CEVAL_H */