def analyze_always_defined_attrs_in_class(cl: ClassIR,
seen: Set[ClassIR]) -> None:
if cl in seen:
return
seen.add(cl)
if (cl.is_trait or cl.inherits_python or cl.allow_interpreted_subclasses
or cl.builtin_base is not None or cl.children is None
or cl.is_serializable()):
# Give up -- we can't enforce that attributes are always defined.
return
# First analyze all base classes. Track seen classes to avoid duplicate work.
for base in cl.mro[1:]:
analyze_always_defined_attrs_in_class(base, seen)
m = cl.get_method('__init__')
if m is None:
cl._always_initialized_attrs = cl.attrs_with_defaults.copy()
cl._sometimes_initialized_attrs = cl.attrs_with_defaults.copy()
return
self_reg = m.arg_regs[0]
cfg = get_cfg(m.blocks)
dirty = analyze_self_leaks(m.blocks, self_reg, cfg)
maybe_defined = analyze_maybe_defined_attrs_in_init(
m.blocks, self_reg, cl.attrs_with_defaults, cfg)
all_attrs: Set[str] = set()
for base in cl.mro:
all_attrs.update(base.attributes)
maybe_undefined = analyze_maybe_undefined_attrs_in_init(
m.blocks,
self_reg,
initial_undefined=all_attrs - cl.attrs_with_defaults,
cfg=cfg)
always_defined = find_always_defined_attributes(m.blocks, self_reg,
all_attrs, maybe_defined,
maybe_undefined, dirty)
always_defined = {a for a in always_defined if not cl.is_deletable(a)}
cl._always_initialized_attrs = always_defined
if dump_always_defined:
print(cl.name, sorted(always_defined))
cl._sometimes_initialized_attrs = find_sometimes_defined_attributes(
m.blocks, self_reg, maybe_defined, dirty)
mark_attr_initialiation_ops(m.blocks, self_reg, maybe_defined, dirty)
# Check if __init__ can run unpredictable code (leak 'self').
any_dirty = False
for b in m.blocks:
for i, op in enumerate(b.ops):
if dirty.after[b, i] and not isinstance(op, Return):
any_dirty = True
break
cl.init_self_leak = any_dirty
def generate_setter(cl: ClassIR,
attr: str,
rtype: RType,
emitter: Emitter) -> None:
attr_field = emitter.attr(attr)
emitter.emit_line('static int')
emitter.emit_line('{}({} *self, PyObject *value, void *closure)'.format(
setter_name(cl, attr, emitter.names),
cl.struct_name(emitter.names)))
emitter.emit_line('{')
deletable = cl.is_deletable(attr)
if not deletable:
emitter.emit_line('if (value == NULL) {')
emitter.emit_line('PyErr_SetString(PyExc_AttributeError,')
emitter.emit_line(' "{} object attribute {} cannot be deleted");'.format(repr(cl.name),
repr(attr)))
emitter.emit_line('return -1;')
emitter.emit_line('}')
# HACK: Don't consider refcounted values as always defined, since it's possible to
# access uninitialized values via 'gc.get_objects()'. Accessing non-refcounted
# values is benign.
always_defined = cl.is_always_defined(attr) and not rtype.is_refcounted
if rtype.is_refcounted:
attr_expr = f'self->{attr_field}'
if not always_defined:
emitter.emit_undefined_attr_check(rtype, attr_expr, '!=')
emitter.emit_dec_ref('self->{}'.format(attr_field), rtype)
if not always_defined:
emitter.emit_line('}')
if deletable:
emitter.emit_line('if (value != NULL) {')
if rtype.is_unboxed:
emitter.emit_unbox('value', 'tmp', rtype, error=ReturnHandler('-1'), declare_dest=True)
elif is_same_type(rtype, object_rprimitive):
emitter.emit_line('PyObject *tmp = value;')
else:
emitter.emit_cast('value', 'tmp', rtype, declare_dest=True)
emitter.emit_lines('if (!tmp)',
' return -1;')
emitter.emit_inc_ref('tmp', rtype)
emitter.emit_line(f'self->{attr_field} = tmp;')
if deletable:
emitter.emit_line('} else')
emitter.emit_line(' self->{} = {};'.format(attr_field,
emitter.c_undefined_value(rtype)))
emitter.emit_line('return 0;')
emitter.emit_line('}')
def generate_setter(cl: ClassIR, attr: str, rtype: RType,
emitter: Emitter) -> None:
attr_field = emitter.attr(attr)
emitter.emit_line('static int')
emitter.emit_line('{}({} *self, PyObject *value, void *closure)'.format(
setter_name(cl, attr, emitter.names), cl.struct_name(emitter.names)))
emitter.emit_line('{')
deletable = cl.is_deletable(attr)
if not deletable:
emitter.emit_line('if (value == NULL) {')
emitter.emit_line('PyErr_SetString(PyExc_AttributeError,')
emitter.emit_line(
' "{} object attribute {} cannot be deleted");'.format(
repr(cl.name), repr(attr)))
emitter.emit_line('return -1;')
emitter.emit_line('}')
if rtype.is_refcounted:
attr_expr = 'self->{}'.format(attr_field)
emitter.emit_undefined_attr_check(rtype, attr_expr, '!=')
emitter.emit_dec_ref('self->{}'.format(attr_field), rtype)
emitter.emit_line('}')
if deletable:
emitter.emit_line('if (value != NULL) {')
if rtype.is_unboxed:
emitter.emit_unbox('value',
'tmp',
rtype,
error=ReturnHandler('-1'),
declare_dest=True)
elif is_same_type(rtype, object_rprimitive):
emitter.emit_line('PyObject *tmp = value;')
else:
emitter.emit_cast('value', 'tmp', rtype, declare_dest=True)
emitter.emit_lines('if (!tmp)', ' return -1;')
emitter.emit_inc_ref('tmp', rtype)
emitter.emit_line('self->{} = tmp;'.format(attr_field))
if deletable:
emitter.emit_line('} else')
emitter.emit_line(' self->{} = {};'.format(
attr_field, emitter.c_undefined_value(rtype)))
emitter.emit_line('return 0;')
emitter.emit_line('}')