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#
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"""FFI registry to register function and objects."""
from __future__ import annotations
import json
import sys
import warnings
from typing import Any, Callable, Literal, Sequence, TypeVar, overload
from . import core
from .core import Function, TypeInfo
# whether we simplify skip unknown objects regtistration
_SKIP_UNKNOWN_OBJECTS = False
_T = TypeVar("_T", bound=type)
[docs]
def register_object(
type_key: str | None = None,
*,
init: bool = True,
) -> Callable[[_T], _T]:
"""Register object type.
Parameters
----------
type_key
The type key of the node. It requires ``type_key`` to be registered already
on the C++ side. If not specified, the class name will be used.
init
If True (default), install ``__init__`` from the C++ ``__ffi_init__``
TypeAttrColumn when available, or a TypeError guard for ``Object``
subclasses that lack one. Set to False when a subsequent decorator
(e.g. ``@c_class``) will handle ``__init__`` installation.
Notes
-----
All :class:`Object` subclasses get ``__slots__ = ()`` by default via the
metaclass, preventing per-instance ``__dict__``. To opt out and allow
arbitrary instance attributes, declare ``__slots__ = ("__dict__",)``
explicitly in the class body::
@tvm_ffi.register_object("test.MyObject")
class MyObject(Object):
__slots__ = ("__dict__",)
Examples
--------
The following code registers MyObject using type key "test.MyObject", if the
type key is already registered on the C++ side.
.. code-block:: python
@tvm_ffi.register_object("test.MyObject")
class MyObject(Object):
pass
"""
def _register(cls: _T, object_name: str) -> _T:
"""Register the object type with the FFI core."""
type_index = core._object_type_key_to_index(object_name)
if type_index is None:
if _SKIP_UNKNOWN_OBJECTS:
return cls
raise ValueError(f"Cannot find object type index for {object_name}")
info = core._register_object_by_index(type_index, cls)
_add_class_attrs(type_cls=cls, type_info=info)
setattr(cls, "__tvm_ffi_type_info__", info)
if init:
_install_init(cls, info)
return cls
if isinstance(type_key, str):
def _decorator_with_name(cls: _T) -> _T:
return _register(cls, type_key)
return _decorator_with_name
def _decorator_default(cls: _T) -> _T:
return _register(cls, cls.__name__)
if type_key is None:
return _decorator_default
if isinstance(type_key, type):
return _decorator_default(type_key)
raise TypeError("type_key must be a string, type, or None")
[docs]
def register_global_func(
func_name: str | Callable[..., Any],
f: Callable[..., Any] | None = None,
override: bool = False,
) -> Any:
"""Register global function.
Parameters
----------
func_name
The function name
f
The function to be registered.
override
Whether override existing entry.
Returns
-------
fregister
Register function if f is not specified.
Examples
--------
.. code-block:: python
import tvm_ffi
# we can use decorator to register a function
@tvm_ffi.register_global_func("mytest.echo")
def echo(x):
return x
# After registering, we can get the function by its name
f = tvm_ffi.get_global_func("mytest.echo")
assert f(1) == 1
# we can also directly register a function
tvm_ffi.register_global_func("mytest.add_one", lambda x: x + 1)
f = tvm_ffi.get_global_func("mytest.add_one")
assert f(1) == 2
See Also
--------
:py:func:`tvm_ffi.get_global_func`
:py:func:`tvm_ffi.remove_global_func`
"""
if not isinstance(func_name, str):
f = func_name
func_name = f.__name__ # ty: ignore[unresolved-attribute]
if not isinstance(func_name, str):
raise ValueError("expect string function name")
def register(myf: Callable[..., Any]) -> Any:
"""Register the global function with the FFI core."""
return core._register_global_func(func_name, myf, override)
if f is not None:
return register(f)
return register
@overload
def get_global_func(name: str, allow_missing: Literal[True]) -> core.Function | None: ...
@overload
def get_global_func(name: str, allow_missing: Literal[False] = False) -> core.Function: ...
[docs]
def get_global_func(name: str, allow_missing: bool = False) -> core.Function | None:
"""Get a global function by name.
Parameters
----------
name
The name of the global function
allow_missing
Whether allow missing function or raise an error.
Returns
-------
func
The function to be returned, ``None`` if function is missing.
Examples
--------
.. code-block:: python
import tvm_ffi
@tvm_ffi.register_global_func("demo.echo")
def echo(x):
return x
f = tvm_ffi.get_global_func("demo.echo")
assert f(123) == 123
See Also
--------
:py:func:`tvm_ffi.register_global_func`
"""
return core._get_global_func(name, allow_missing)
def list_global_func_names() -> list[str]:
"""Get list of global functions registered.
Returns
-------
names
List of global functions names.
"""
name_functor = get_global_func("ffi.FunctionListGlobalNamesFunctor")()
num_names = name_functor(-1)
return [name_functor(i) for i in range(num_names)]
[docs]
def remove_global_func(name: str) -> None:
"""Remove a global function by name.
Parameters
----------
name
The name of the global function.
Examples
--------
.. code-block:: python
import tvm_ffi
@tvm_ffi.register_global_func("my.temp")
def temp():
return 42
assert tvm_ffi.get_global_func("my.temp", allow_missing=True) is not None
tvm_ffi.remove_global_func("my.temp")
assert tvm_ffi.get_global_func("my.temp", allow_missing=True) is None
See Also
--------
:py:func:`tvm_ffi.register_global_func`
:py:func:`tvm_ffi.get_global_func`
"""
get_global_func("ffi.FunctionRemoveGlobal")(name)
[docs]
def init_ffi_api(namespace: str, target_module_name: str | None = None) -> None:
"""Initialize register ffi api functions into a given module.
Parameters
----------
namespace
The namespace of the source registry
target_module_name
The target module name if different from namespace
Examples
--------
A typical usage pattern is to create a _ffi_api.py file to register
the functions under a given module. The following
code populates all registered global functions
prefixed with ``mypackage.`` into the current module,
then we can call the function through ``_ffi_api.func_name(*args)``
which will call into the registered global function "mypackage.func_name".
.. code-block:: python
# _ffi_api.py
import tvm_ffi
tvm_ffi.init_ffi_api("mypackage", __name__)
"""
target_module_name = target_module_name if target_module_name else namespace
if namespace.startswith("tvm."):
prefix = namespace[4:]
else:
prefix = namespace
target_module = sys.modules[target_module_name]
for name in list_global_func_names():
if not name.startswith(prefix):
continue
fname = name[len(prefix) + 1 :]
if fname.find(".") != -1:
continue
f = get_global_func(name)
setattr(f, "__name__", fname)
setattr(target_module, fname, f)
def _install_init(cls: type, type_info: TypeInfo) -> None:
"""Install ``__init__`` from ``__ffi_init__`` TypeMethod or TypeAttrColumn.
Skipped if the class body already defines ``__init__``.
This ensures that ``register_object`` alone provides a working
constructor, maintaining the invariant that ``c_class`` is a full
alias of ``register_object`` + dunder installation.
When no ``__ffi_init__`` is available and the class is an ``Object``
subclass, a TypeError guard is installed to prevent segfaults from
uninitialised handles.
"""
if "__init__" in cls.__dict__:
return
# Look up __ffi_init__ from TypeMethod (preferred) or TypeAttrColumn (fallback).
ffi_init = None
for method in type_info.methods:
if method.name == "__ffi_init__":
ffi_init = method.func
break
if ffi_init is None:
ffi_init = core._lookup_type_attr(type_info.type_index, "__ffi_init__")
if ffi_init is not None:
from ._dunder import _make_init # noqa: PLC0415
cls.__init__ = _make_init( # type: ignore[attr-defined]
cls,
type_info,
ffi_init=ffi_init,
)
elif issubclass(cls, core.Object):
type_name = cls.__name__
def __init__(self: Any, *args: Any, **kwargs: Any) -> None:
raise TypeError(
f"`{type_name}` cannot be constructed directly. "
f"Define a custom __init__ or use a factory method."
)
__init__.__qualname__ = f"{cls.__qualname__}.__init__"
__init__.__module__ = cls.__module__
cls.__init__ = __init__ # type: ignore[attr-defined]
def _add_class_attrs(type_cls: type, type_info: TypeInfo) -> type:
for field in type_info.fields:
name = field.name
if not hasattr(type_cls, name): # skip already defined attributes
setattr(type_cls, name, field.as_property(type_cls))
has_ffi_init = False
for method in type_info.methods:
name = method.name
if name == "__ffi_init__":
_install_ffi_init_attr(type_cls, type_info, method.func)
has_ffi_init = True
continue
if not hasattr(type_cls, name):
setattr(type_cls, name, method.as_callable(type_cls))
# Also check TypeAttrColumn for auto-generated __ffi_init__.
if not has_ffi_init:
ffi_init = core._lookup_type_attr(type_info.type_index, "__ffi_init__")
if ffi_init is not None:
_install_ffi_init_attr(type_cls, type_info, ffi_init)
return type_cls
def _install_ffi_init_attr(cls: type, type_info: TypeInfo, ffi_init: Function) -> None:
"""Install ``__ffi_init__`` as a method that delegates to ``__init_handle_by_constructor__``.
Custom ``__init__`` methods call ``self.__ffi_init__(*args, **kwargs)`` to
construct the underlying C++ object. This installs a wrapper that translates
that call into ``self.__init_handle_by_constructor__(ffi_init, *ffi_args)``
with kwargs packed using the FFI KWARGS protocol.
The wrapper includes a type-owner guard (same as ``_make_init``) to prevent
subclasses from accidentally using a parent's ``__ffi_init__``.
"""
kwargs_obj = core.KWARGS
missing = core.MISSING
type_name = cls.__name__
def __ffi_init__(self: Any, *args: Any, **kwargs: Any) -> None:
if type_info is not type(self).__tvm_ffi_type_info__:
raise TypeError(
f"Calling `{type_name}.__ffi_init__()` on a `{type(self).__name__}` "
f"instance is not supported. Define `{type(self).__name__}` with init=True."
)
ffi_args: list[Any] = list(args)
if kwargs:
ffi_args.append(kwargs_obj)
for key, val in kwargs.items():
if val is not missing:
ffi_args.append(key)
ffi_args.append(val)
self.__init_handle_by_constructor__(ffi_init, *ffi_args)
__ffi_init__.__qualname__ = f"{cls.__qualname__}.__ffi_init__"
__ffi_init__.__module__ = cls.__module__
cls.__ffi_init__ = __ffi_init__ # type: ignore[attr-defined]
def _warn_missing_field_annotations(cls: type, type_info: TypeInfo, *, stacklevel: int) -> None:
"""Emit a warning if any C++ reflected fields lack Python annotations on *cls*.
Only checks fields owned by *type_info* (not inherited from parents).
Only checks annotations defined directly on *cls* (``cls.__dict__``),
so parent annotations do not suppress warnings for child-level fields.
"""
reflected_names = {field.name for field in type_info.fields}
if not reflected_names:
return
own_annotations = cls.__dict__.get("__annotations__", {})
missing = sorted(reflected_names - set(own_annotations))
if missing:
missing_str = ", ".join(missing)
warnings.warn(
f"@c_class({type_info.type_key!r}): class `{cls.__qualname__}` does not "
f"annotate the following reflected field(s): {missing_str}. "
f"Add type annotations (e.g. `field_name: type`) to the class body "
f"for IDE support and documentation.",
UserWarning,
stacklevel=stacklevel,
)
def get_registered_type_keys() -> Sequence[str]:
"""Get the list of valid type keys registered to TVM-FFI.
Returns
-------
type_keys
List of valid type keys.
"""
return get_global_func("ffi.GetRegisteredTypeKeys")()
__all__ = [
"get_global_func",
"get_global_func_metadata",
"get_registered_type_keys",
"init_ffi_api",
"list_global_func_names",
"register_global_func",
"register_object",
"remove_global_func",
]