blob: 5b3d039e62576c3279b663fed191732c1b271986 [file] [log] [blame]
"""
The weak_script annotation needs to be here instead of inside torch/jit/ so it
can be used in other places in torch/ (namely torch.nn) without running into
circular dependency problems
"""
import inspect
import weakref
import torch._C
from torch._six import builtins
# Wrapper functions that can call either of 2 functions depending on a boolean
# argument
boolean_dispatched = weakref.WeakKeyDictionary() # noqa: T484
def createResolutionCallback(frames_up=0):
"""
Creates a function which, given a string variable name,
returns the value of the variable in the scope of the caller of
the function which called createResolutionCallback (by default).
This is used to enable access in-scope Python variables inside
TorchScript fragments.
frames_up is number of additional frames to go up on the stack.
The default value is 0, which correspond to the frame of the caller
of createResolutionCallback. Also for example, if frames_up is set
to 1, then the frame of the caller's caller of createResolutionCallback
will be taken.
For example, the following program prints 2::
def bar():
cb = createResolutionCallback(1)
print(cb("foo"))
def baz():
foo = 2
bar()
baz()
"""
frame = inspect.currentframe()
i = 0
while i < frames_up + 1:
frame = frame.f_back
i += 1
f_locals = frame.f_locals
f_globals = frame.f_globals
def env(key):
if key in f_locals:
return f_locals[key]
elif key in f_globals:
return f_globals[key]
elif hasattr(builtins, key):
return getattr(builtins, key)
return env
def get_closure(fn):
"""
Get a dictionary of closed over variables from a function
"""
captures = {}
captures.update(fn.__globals__)
for index, captured_name in enumerate(fn.__code__.co_freevars):
captures[captured_name] = fn.__closure__[index].cell_contents
return captures
def createResolutionCallbackFromClosure(fn):
"""
Create a resolutionCallback by introspecting the function instead of
looking up the stack for the enclosing scope
"""
closure = get_closure(fn)
def env(key):
if key in closure:
return closure[key]
elif hasattr(builtins, key):
return getattr(builtins, key)
return None
return env
def can_compile_class(cls):
# If any of the functions on a type don't have a code object, this type can't
# be compiled and is probably a builtin / bound from C
fns = [getattr(cls, name) for name in cls.__dict__ if inspect.isroutine(getattr(cls, name))]
has_code = [hasattr(fn, '__code__') for fn in fns]
return all(has_code)
def createResolutionCallbackForClassMethods(cls):
"""
This looks at all the methods defined in a class and pulls their closed-over
variables into a dictionary and uses that to resolve variables.
"""
# cls is a type here, so `ismethod` is false since the methods on the type
# aren't bound to anything, so Python treats them as regular functions
fns = [getattr(cls, name) for name in cls.__dict__ if inspect.isroutine(getattr(cls, name))]
captures = {}
for fn in fns:
captures.update(get_closure(fn))
return lambda key: captures.get(key, None)
def boolean_dispatch(arg_name, arg_index, default, if_true, if_false, module_name, func_name):
"""
Dispatches to either of 2 script functions based on a boolean argument.
In TorchScript, the boolean argument must be constant so that the correct
function to use can be determined at compile time.
"""
def fn(*args, **kwargs):
dispatch_flag = False
if arg_name in kwargs:
dispatch_flag = kwargs[arg_name]
elif arg_index < len(args):
dispatch_flag = args[arg_index]
if dispatch_flag:
return if_true(*args, **kwargs)
else:
return if_false(*args, **kwargs)
if if_true.__doc__ is None and if_false.__doc__ is not None:
doc = if_false.__doc__
if_true.__doc__ = doc
elif if_false.__doc__ is None and if_true.__doc__ is not None:
doc = if_true.__doc__
if_false.__doc__ = doc
elif if_false.__doc__ is None and if_true.__doc__ is None:
# neither function has a docstring
doc = None
else:
raise RuntimeError("only one function can have a docstring")
fn.__doc__ = doc
if module_name is not None:
fn.__module__ = module_name
if func_name is not None:
fn.__name__ = func_name
boolean_dispatched[fn] = {
"if_true": if_true,
"if_false": if_false,
"index": arg_index,
"default": default,
"arg_name": arg_name
}
return fn
class FunctionModifiers(object):
"""
Used to denote the behavior of a function in TorchScript. See export() and
ignore() for details.
"""
IGNORE_AND_DROP = "ignore (leave as a call to Python, replace with a 'raise' on torch.jit.save)"
IGNORE = "ignore (leave as a call to Python, cannot be torch.jit.save'd)"
EXPORT = "export (compile this function even if nothing calls it)"
DEFAULT = "default (compile if called from a exported function / forward)"
def export(fn):
"""
This decorator indicates that a method is used as an entry point into a
ScriptModule. `forward` implicitly is used as an entry point, so it does
not need this decorator.
Methods are added to a ScriptModule as they are called in Python. If a
method is never called, it will not be included in the ScriptModule when
saving. This decorator explicitly marks that a method should be included
even if it is not called from Python.
"""
fn._torchscript_modifier = FunctionModifiers.EXPORT
return fn
def ignore(drop_on_export=False):
"""
This decorator indicates to the compiler that a function or method should
be ignored and left as a Python function.
With `drop_on_export=False` (the default), calls to this function will
prevent saving a TorchScript model.
With `drop_on_export=True`, any calls to this function from other
TorchScript code will be replaced with a `raise`. This allows you to leave
code in your TorchScript model that is only ever run when the Python
interpreter is present.
"""
if callable(drop_on_export):
# used without any args, so drop_on_export is actually a function
# @torch.jit.ignore
# def fn(...):
fn = drop_on_export
fn._torchscript_modifier = FunctionModifiers.IGNORE
return fn
if isinstance(drop_on_export, bool):
def decorator(fn):
if drop_on_export:
fn._torchscript_modifier = FunctionModifiers.IGNORE_AND_DROP
else:
fn._torchscript_modifier = FunctionModifiers.IGNORE
return fn
return decorator
raise RuntimeError("Argument to @torch.jit.ignore must be a bool or "
"a function but got {}".format(drop_on_export))
def should_drop_on_export(fn):
attr = get_torchscript_modifier(fn)
if attr is None:
return False
return attr is FunctionModifiers.IGNORE_AND_DROP
def is_ignored_fn(fn):
mod = get_torchscript_modifier(fn)
return mod is FunctionModifiers.IGNORE_AND_DROP or mod is FunctionModifiers.IGNORE
def get_torchscript_modifier(fn):
if not callable(fn):
return None
if hasattr(fn, '__func__'):
fn = fn.__func__
return getattr(fn, '_torchscript_modifier', FunctionModifiers.DEFAULT)
def _parameter_list(parameter_names_fn):
"""
Decorator to denote that a function returns a list of all the parameters
in a module
"""
def decorator(fn):
fn._parameter_names_fn = parameter_names_fn
return fn
return decorator
# overloading registration
# overloads get registered in this file, and compiled in torch/jit/__init__.py
# so that they can be imported in nn/functional.py without an import cycle
# qualified_name => list[overload_functions]
_overloaded_fns = {} # noqa: T484
def _overload(func):
qual_name = _qualified_name(func)
global _overloaded_fns
fn_overload_list = _overloaded_fns.get(qual_name)
if fn_overload_list is None:
fn_overload_list = []
_overloaded_fns[qual_name] = fn_overload_list
fn_overload_list.append(func)
return func
def _get_fn_overloads(qual_name):
return _overloaded_fns.get(qual_name)
def _clear_fn_overloads(qual_name):
del _overloaded_fns[qual_name]
try:
import typing
from typing import Tuple, List, Dict, Optional
def is_tuple(ann):
# For some reason Python 3.7 violates the Type[A, B].__origin__ == Type rule
return ann.__module__ == 'typing' and \
(getattr(ann, '__origin__', None) is typing.Tuple or
getattr(ann, '__origin__', None) is tuple)
def is_list(ann):
return ann.__module__ == 'typing' and \
(getattr(ann, '__origin__', None) is typing.List or
getattr(ann, '__origin__', None) is list)
def is_dict(ann):
return ann.__module__ == 'typing' and \
(getattr(ann, '__origin__', None) is typing.Dict or
getattr(ann, '__origin__', None) is dict)
def is_optional(ann):
# Optional[T] is just shorthand for Union[T, None], so check for both
union_optional = False
if ann.__module__ == 'typing' and \
(getattr(ann, '__origin__', None) is typing.Union):
args = getattr(ann, '__args__', ())
if len(args) == 2:
union_optional = (issubclass(args[1], type(None)) and not issubclass(args[0], type(None))) \
or (issubclass(args[0], type(None)) and not issubclass(args[1], type(None)))
optional = ann.__module__ == 'typing' and \
(getattr(ann, '__origin__', None) is typing.Optional)
return optional or union_optional
except ImportError:
# A minimal polyfill for versions of Python that don't have typing.
# Note that this means that they also don't support the fancy annotation syntax, so
# those instances will only be used in our tiny `type: ` comment interpreter.
# The __getitem__ in typing is implemented using metaclasses, but I'm too lazy for that.
class TupleCls(object):
def __getitem__(self, types):
return TupleInstance(types)
class TupleInstance(object):
__slots__ = ['__args__']
def __init__(self, types):
self.__args__ = types
class ListInstance(object):
__slots__ = ['__args__']
def __init__(self, types):
self.__args__ = types
class ListCls(object):
def __getitem__(self, types):
return TupleInstance(types)
class DictInstance(object):
__slots__ = ['__args__']
def __init__(self, types):
self.__args__ = types
class DictCls(object):
def __getitem__(self, types):
return DictInstance(types)
class OptionalInstance(object):
__slots__ = ['__args__']
def __init__(self, types):
self.__args__ = types
class OptionalCls(object):
def __getitem__(self, types):
return OptionalInstance(types)
Tuple = TupleCls() # noqa: T484
List = ListCls() # noqa: T484
Dict = DictCls() # noqa: T484
Optional = DictCls() # noqa: T484
def is_tuple(ann):
return isinstance(ann, TupleInstance)
def is_list(ann):
return isinstance(ann, ListInstance)
def is_dict(ann):
return isinstance(ann, DictInstance)
def is_optional(ann):
return isinstance(ann, OptionalInstance)
try:
import typing_extensions
from typing_extensions import Final
def is_final(ann):
return ann.__module__ == 'typing_extensions' and \
(getattr(ann, '__origin__', None) is typing_extensions.Final)
except ImportError:
# Same as above, this polyfill is only for `typing_extensions`
class FinalInstance(object):
__slots__ = ['__args__']
def __init__(self, types):
self.__args__ = types
class FinalCls(object):
def __getitem__(self, types):
return FinalInstance(types)
Final = FinalCls() # noqa: T484
def is_final(ann):
return isinstance(ann, FinalInstance)
# allows BroadcastingList instance to be subscriptable
class BroadcastingListCls(object):
def __getitem__(self, types):
return
# mypy doesn't support parameters on types, so we have to explicitly type each
# list size
BroadcastingList1 = BroadcastingListCls()
for i in range(2, 7):
globals()["BroadcastingList{}".format(i)] = BroadcastingList1
# Retrieves a fully-qualified name (module hierarchy + classname) for a given obj.
def _qualified_name(obj):
# short-circuit in cases where the object already has a known qualified name
if isinstance(obj, torch._C.Function):
return obj.qualified_name
name = obj.__name__
module_name = obj.__module__
# If the module is actually a torchbind module, then we should short circuit
if module_name == "torch._classes":
return obj.qualified_name
# The Python docs are very clear that `__module__` can be None, but I can't
# figure out when it actually would be.
if module_name is None:
raise RuntimeError("Could not get qualified name for class '{}': "
"__module__ can't be None.".format(name))
# if getattr(sys.modules[module_name], name) is not obj:
# raise RuntimeError("Could not get qualified name for class '{}': "
# "the attr {} on module {} is not the the class".format(name, name, module_name))
# __main__ is a builtin module, so rewrite it to "__torch__".
if module_name == "__main__":
module_name = "__torch__"
else:
# Everything else gets a "__torch__" prefix to avoid name collisions
# with the names of user values.
module_name = "__torch__." + module_name
if "." in name:
raise RuntimeError("Could not get qualified name for class '{}': "
"'{}' is not a valid identifier".format(name, name))
return module_name + "." + name