pytorch/torch/_subclasses/schema_check_mode.py
Pian Pawakapan 2973c9bb88 [export] add SchemaCheckMode testing for pre-dispatch export, OpInfo (#125481)
This adds a new dispatch mode, PreDispatchSchemaCheckMode, built on top of SchemaCheckMode, used for verifying op schemas for functionalization for PreDispatch IR. More specifically, the mode runs in eager mode on concrete inputs, checking if op schemas incorrectly claim to be functional, but are aliasing or mutating. This mode is pushed to the pre-dispatch mode stack, and run before decompositions.

Current testing is hooked up to OpInfo, containing 1103 tests on 600 unique ops. Below is a list of ops that fail testing. One caveat is we only raise errors on ops that claim to be functional - if an op schema admits aliasing or mutating but fails testing for the other, it still may decompose further and become functional.

List of failed ops:
```
aten.atleast_1d.default
aten.atleast_2d.default
aten.atleast_3d.default
aten.cartesian_prod.default
aten.conj_physical.default
aten.alpha_dropout.default
aten.feature_dropout.default
aten.feature_alpha_dropout.default
aten.unsafe_chunk.default
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/125481
Approved by: https://github.com/tugsbayasgalan
2024-05-14 21:07:21 +00:00

229 lines
8.4 KiB
Python

# mypy: ignore-errors
from collections import namedtuple
from copy import deepcopy
from itertools import combinations
import torch
from torch.fx.operator_schemas import normalize_function
from torch.utils import _pytree as pytree
from torch.utils._python_dispatch import TorchDispatchMode
from torch.utils._pytree import tree_map
# Named Tuples used within SchemaCheckMode
Mutation = namedtuple("Mutation", ["op_name", "arg_name"])
Aliasing = namedtuple("Aliasing", ["op_name", "arg_name", "output_number"])
# Simplified naming for C++ classes
SchemaArgument = torch._C._SchemaArgument
SchemaArgType = torch._C._SchemaArgType
SchemaInfo = torch._C._SchemaInfo
# This TorchDispatchMode Subclass is used to verify op schemas
# This TorchDispatchMode Scubclass currently:
# - Records the called ops
# - Checks for mutations on all inputs
# - Checks for aliasing on all inputs
# move these 2 functions here to avoid numpy dependency in testing/_internal/common_utils.py
def is_iterable_of_tensors(iterable):
# Tensor itself is iterable so we check this first
if isinstance(iterable, torch.Tensor):
return False
try:
if len(iterable) == 0:
return False
for t in iter(iterable):
if not isinstance(t, torch.Tensor):
return False
except TypeError as te:
return False
return True
def clone_inputs(args):
inputs = []
for arg in args:
if isinstance(arg, torch.Tensor):
inputs.append(arg.detach().clone())
elif is_iterable_of_tensors(arg):
inputs.append([t.detach().clone() for t in arg])
else:
inputs.append(arg)
return inputs
class SchemaCheckMode(TorchDispatchMode):
def __init__(self):
# Information recorded for testing purposes. For example:
# - incorrect schemas
# - overly conservative schemas
self.ops = []
self.mutated = []
self.aliasing = []
def reset_cache(self):
self.ops.clear()
self.mutated.clear()
self.aliasing.clear()
def display_ops(self):
print(*self.ops, sep=",")
def __torch_dispatch__(self, func, types, args=(), kwargs=None):
def bitwise_equal(lhs, rhs):
if lhs.is_quantized:
# TODO: This is only OK if can't have NaN quantized; idk if
# this is actually true
return torch.equal(lhs, rhs)
else:
return torch.allclose(lhs, rhs, equal_nan=True)
def has_mutated(before, after, md):
are_tensors = type(before) == torch.Tensor and type(after) == torch.Tensor
if (
are_tensors
and before.layout != torch.sparse_csr
and after.layout != torch.sparse_csr
):
return not (
before.size() == after.size()
and bitwise_equal(before, after)
and md[0] == after.stride()
and md[1] == after._typed_storage()._cdata
)
return False
def has_aliased(lhs, rhs):
try:
return torch._C._overlaps(lhs, rhs)
except Exception as exception:
if str(exception).startswith("Cannot inspect value of type "):
return False
else:
raise exception
def standardize_name(name):
return name if name != "self" else "input"
def unwrap(e):
if isinstance(e, torch.Tensor) and not type(e) == torch.Tensor:
try:
return e.elem
except AttributeError as t:
return e
return e
def parse_metadata(e):
if isinstance(e, torch.Tensor):
if not type(e) == torch.Tensor:
try:
current = e.elem
return (
deepcopy(current.stride()),
current._typed_storage()._cdata,
)
except AttributeError as t:
return None
# Sparse CSR tensors do not have strides or storage
elif e.layout != torch.sparse_csr:
return (deepcopy(e.stride()), e._typed_storage()._cdata)
return None
self.ops.append(func._schema.name)
# Clone and process arguments and outputs
pre_arguments = normalize_function(
func, args, kwargs, normalize_to_only_use_kwargs=True
).kwargs
c_p_args = dict(zip(pre_arguments.keys(), clone_inputs(pre_arguments.values())))
cloned_arguments = {
name: tree_map(unwrap, c_p_args.get(name)) for name in c_p_args
}
cloned_metadata = {
name: [
parse_metadata(a) for a in pytree.tree_leaves(pre_arguments.get(name))
]
for name in pre_arguments
}
out = func(*args, **kwargs)
arguments = {
name: tree_map(unwrap, pre_arguments.get(name)) for name in pre_arguments
}
tuple_out = out if isinstance(out, tuple) else (out,)
tuple_out = tree_map(unwrap, tuple_out)
schema_info = SchemaInfo(func._schema)
schema_info.add_argument_values(pre_arguments)
# Process arguments with outputs
for i in range(len(func._schema.arguments)):
arg = func._schema.arguments[i]
name = standardize_name(arg.name)
if arguments.get(name) is not None:
before = cloned_arguments.get(name)
md = cloned_metadata.get(name)
after = arguments.get(name)
for j in range(len(tuple_out)):
# aten::_unsafe_view is intended to have incorrect aliasing notation (hence unsafe)
unsafe_ops = ("aten::_unsafe_view", "aten::unsafe_split")
if (
has_aliased(tuple_out[j], after)
and func._schema.name not in unsafe_ops
):
if not schema_info.may_contain_alias(
SchemaArgument(SchemaArgType.output, j),
SchemaArgument(SchemaArgType.input, i),
):
raise RuntimeError(
f"Argument {name} is not defined to alias output but was aliasing"
)
else:
self.aliasing.append(
Aliasing(func._schema.name, name, f"output_{j}")
)
if after is tuple_out[j] and isinstance(after, torch.Tensor):
# Only mutable ops e.g. (add_, add.out) are allowed to directly return inputs.
if not schema_info.is_mutable(
SchemaArgument(SchemaArgType.input, i)
) and func not in [
torch.ops.aten.lift.default,
torch.ops.aten.lift_fresh.default,
]:
raise RuntimeError(
f"""\
Dispatcher operators below autograd are not allowed to directly return inputs.
However, we found that `outputs[{str(j)}] is {name}"""
)
if any(
has_mutated(a, b, c)
for a, b, c in zip(
pytree.tree_leaves(before), pytree.tree_leaves(after), md
)
):
if not schema_info.is_mutable(
SchemaArgument(SchemaArgType.input, i)
):
raise RuntimeError(
f"Argument {name} is not defined as mutable but was mutated"
)
else:
self.mutated.append(Mutation(func._schema.name, name))
# Aliasing between outputs
for i, j in combinations(range(len(func._schema.returns)), 2):
if has_aliased(tuple_out[i], tuple_out[j]):
if not schema_info.may_contain_alias(
SchemaArgument(SchemaArgType.output, i),
SchemaArgument(SchemaArgType.output, j),
):
raise RuntimeError(f"Outputs {i} and {j} alias unexpectedly")
return out