diff options
Diffstat (limited to 'Python/specialize.c')
| -rw-r--r-- | Python/specialize.c | 78 |
1 files changed, 41 insertions, 37 deletions
diff --git a/Python/specialize.c b/Python/specialize.c index 06995d46d8b..92f79d39d55 100644 --- a/Python/specialize.c +++ b/Python/specialize.c @@ -2904,53 +2904,57 @@ int #endif // Py_STATS Py_NO_INLINE void -_Py_Specialize_ForIter(_PyStackRef iter, _Py_CODEUNIT *instr, int oparg) +_Py_Specialize_ForIter(_PyStackRef iter, _PyStackRef null_or_index, _Py_CODEUNIT *instr, int oparg) { assert(ENABLE_SPECIALIZATION_FT); assert(_PyOpcode_Caches[FOR_ITER] == INLINE_CACHE_ENTRIES_FOR_ITER); PyObject *iter_o = PyStackRef_AsPyObjectBorrow(iter); PyTypeObject *tp = Py_TYPE(iter_o); + + if (PyStackRef_IsNull(null_or_index)) { #ifdef Py_GIL_DISABLED - // Only specialize for uniquely referenced iterators, so that we know - // they're only referenced by this one thread. This is more limiting - // than we need (even `it = iter(mylist); for item in it:` won't get - // specialized) but we don't have a way to check whether we're the only - // _thread_ who has access to the object. - if (!_PyObject_IsUniquelyReferenced(iter_o)) - goto failure; -#endif - if (tp == &PyListIter_Type) { -#ifdef Py_GIL_DISABLED - _PyListIterObject *it = (_PyListIterObject *)iter_o; - if (!_Py_IsOwnedByCurrentThread((PyObject *)it->it_seq) && - !_PyObject_GC_IS_SHARED(it->it_seq)) { - // Maybe this should just set GC_IS_SHARED in a critical - // section, instead of leaving it to the first iteration? + // Only specialize for uniquely referenced iterators, so that we know + // they're only referenced by this one thread. This is more limiting + // than we need (even `it = iter(mylist); for item in it:` won't get + // specialized) but we don't have a way to check whether we're the only + // _thread_ who has access to the object. + if (!_PyObject_IsUniquelyReferenced(iter_o)) { goto failure; } #endif - specialize(instr, FOR_ITER_LIST); - return; - } - else if (tp == &PyTupleIter_Type) { - specialize(instr, FOR_ITER_TUPLE); - return; - } - else if (tp == &PyRangeIter_Type) { - specialize(instr, FOR_ITER_RANGE); - return; + if (tp == &PyRangeIter_Type) { + specialize(instr, FOR_ITER_RANGE); + return; + } + else if (tp == &PyGen_Type && oparg <= SHRT_MAX) { + // Generators are very much not thread-safe, so don't worry about + // the specialization not being thread-safe. + assert(instr[oparg + INLINE_CACHE_ENTRIES_FOR_ITER + 1].op.code == END_FOR || + instr[oparg + INLINE_CACHE_ENTRIES_FOR_ITER + 1].op.code == INSTRUMENTED_END_FOR + ); + /* Don't specialize if PEP 523 is active */ + if (_PyInterpreterState_GET()->eval_frame) { + goto failure; + } + specialize(instr, FOR_ITER_GEN); + return; + } } - else if (tp == &PyGen_Type && oparg <= SHRT_MAX) { - // Generators are very much not thread-safe, so don't worry about - // the specialization not being thread-safe. - assert(instr[oparg + INLINE_CACHE_ENTRIES_FOR_ITER + 1].op.code == END_FOR || - instr[oparg + INLINE_CACHE_ENTRIES_FOR_ITER + 1].op.code == INSTRUMENTED_END_FOR - ); - /* Don't specialize if PEP 523 is active */ - if (_PyInterpreterState_GET()->eval_frame) - goto failure; - specialize(instr, FOR_ITER_GEN); - return; + else { + if (tp == &PyList_Type) { +#ifdef Py_GIL_DISABLED + // Only specialize for lists owned by this thread or shared + if (!_Py_IsOwnedByCurrentThread(iter_o) && !_PyObject_GC_IS_SHARED(iter_o)) { + goto failure; + } +#endif + specialize(instr, FOR_ITER_LIST); + return; + } + else if (tp == &PyTuple_Type) { + specialize(instr, FOR_ITER_TUPLE); + return; + } } failure: SPECIALIZATION_FAIL(FOR_ITER, |