team-10/env/Lib/site-packages/torch/_dynamo/variables/lazy.py
2025-08-02 07:34:44 +02:00

213 lines
6.8 KiB
Python

import collections
import functools
import inspect
from typing import Any, Callable, final, Optional, Union
from typing_extensions import Self
from ..utils import is_function_or_wrapper
from .base import VariableTracker
from .tensor import SymNodeVariable
class LazyCache:
"""Container to cache the real VariableTracker"""
def __init__(self, value: Any, source: Any) -> None:
if not isinstance(value, LazySymNodeFormatString):
assert source
self.value = value
self.source = source
self.vt: Optional[VariableTracker] = None
def realize(self) -> None:
assert self.vt is None
from ..symbolic_convert import InstructionTranslator
tx = InstructionTranslator.current_tx()
if isinstance(self.value, LazySymNodeFormatString):
source = None
else:
source = self.source
self.vt = VariableTracker.build(tx, self.value, source)
del self.value
del self.source
@final
class LazyVariableTracker(VariableTracker):
"""
A structure that defers the creation of the actual VariableTracker
for a given underlying value until it is accessed.
The `realize` function invokes VariableTracker.build() to produce the real object.
Once a LazyVariableTracker has been realized, internal bookkeeping will
prevent double realization.
This object should be utilized for processing containers, or objects that
reference other objects where we may not want to take on creating all the
VariableTrackers right away.
"""
_nonvar_fields = {"_cache", *VariableTracker._nonvar_fields}
@staticmethod
def create(value: Any, source: Any, **options: Any) -> "LazyVariableTracker":
return LazyVariableTracker(LazyCache(value, source), source=source, **options)
def __init__(self, _cache: LazyCache, **kwargs: Any) -> None:
assert isinstance(_cache, LazyCache)
super().__init__(**kwargs)
self._cache = _cache
def realize(self) -> VariableTracker:
"""Force construction of the real VariableTracker"""
if self._cache.vt is None:
self._cache.realize()
assert self._cache.vt is not None
return self._cache.vt
def unwrap(self) -> Union[VariableTracker, Self]:
"""Return the real VariableTracker if it already exists"""
if self.is_realized():
assert self._cache.vt is not None
return self._cache.vt
return self
def is_realized(self) -> bool:
return self._cache.vt is not None
def clone(self, **kwargs: Any) -> VariableTracker:
assert kwargs.get("_cache", self._cache) is self._cache
if kwargs.get("source", self.source) is not self.source:
self.realize()
return VariableTracker.clone(self.unwrap(), **kwargs)
def peek_type(self) -> type[Any]:
assert not self.is_realized()
return type(self._cache.value)
def peek_value(self) -> Any:
assert not self.is_realized()
return self._cache.value
def __str__(self) -> str:
if self.is_realized():
return repr(self.unwrap())
return super().__repr__()
def __getattr__(self, item: str) -> Any:
return getattr(self.realize(), item)
# most methods are auto-generated below, these are the ones we want to exclude
visit = VariableTracker.visit # type: ignore[assignment]
__repr__ = __str__
@classmethod
def realize_all(
cls,
value: Any,
cache: Optional[dict[int, tuple[Any, Any]]] = None,
) -> Any:
"""
Walk an object and realize all LazyVariableTrackers inside it.
"""
if cache is None:
cache = {}
idx = id(value)
if idx in cache:
return cache[idx][0]
value_cls = type(value)
if issubclass(value_cls, LazyVariableTracker):
result = cls.realize_all(value.realize(), cache)
elif issubclass(value_cls, VariableTracker):
# update value in-place
result = value
value_dict = value.__dict__
nonvars = value._nonvar_fields
for key in value_dict:
if key not in nonvars:
value_dict[key] = cls.realize_all(value_dict[key], cache)
elif value_cls is list:
result = [cls.realize_all(v, cache) for v in value]
elif value_cls is tuple:
result = tuple(cls.realize_all(v, cache) for v in value)
elif value_cls in (dict, collections.OrderedDict):
result = {k: cls.realize_all(v, cache) for k, v in list(value.items())}
else:
result = value
# save `value` to keep it alive and ensure id() isn't reused
cache[idx] = (result, value)
return result
def is_hashable(self) -> bool:
# Checks that the underlying value is hashable without realizing the VT.
# This is used by ConstDictVariable tracker to find if the key LazyVT
# can be hashed.
def _helper(value: Any) -> bool:
# TODO: Add support for more types
return (
inspect.isbuiltin(value)
or issubclass(type(value), type)
or is_function_or_wrapper(value)
)
assert not self.is_realized()
value = self._cache.value
if isinstance(value, tuple):
return all(_helper(v) for v in value)
return _helper(value)
def original_value(self) -> Any:
# Returns the value without realizing the VT.
assert not self.is_realized()
return self._cache.value
def original_source(self) -> Any:
# Returns the source without realizing the VT.
assert not self.is_realized()
return self._cache.source
class LazySymNodeFormatString:
def __init__(
self, sym_node_variable: SymNodeVariable, fmt_spec_var: VariableTracker
) -> None:
from .constant import ConstantVariable
self.sym_node_var = sym_node_variable
self.fmt_var = ConstantVariable.create(
"{:" + fmt_spec_var.as_python_constant() + "}"
)
def __repr__(self) -> str:
return str.format(
self.fmt_var.as_python_constant(),
str(self.sym_node_var.evaluate_expr()),
)
def _create_realize_and_forward(
name: str,
) -> Callable[[LazyVariableTracker, Any, Any], Any]:
@functools.wraps(getattr(VariableTracker, name))
def realize_and_forward(
self: LazyVariableTracker, *args: Any, **kwargs: Any
) -> Any:
return getattr(self.realize(), name)(*args, **kwargs)
return realize_and_forward
def _populate() -> None:
for name, value in VariableTracker.__dict__.items():
if name not in LazyVariableTracker.__dict__:
if callable(value):
setattr(LazyVariableTracker, name, _create_realize_and_forward(name))
_populate()