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pytorch/torch/_inductor/pattern_matcher.py
PyTorch MergeBot 99f2491af9 Revert "Use absolute path path.resolve() -> path.absolute() (#129409)"
This reverts commit 45411d1fc9a2b6d2f891b6ab0ae16409719e09fc.

Reverted https://github.com/pytorch/pytorch/pull/129409 on behalf of https://github.com/jeanschmidt due to Breaking internal CI, @albanD please help get this PR merged ([comment](https://github.com/pytorch/pytorch/pull/129409#issuecomment-2571316444))
2025-01-04 14:17:20 +00:00

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71 KiB
Python

# mypy: allow-untyped-decorators
"""
# Inductor Pattern Matcher
The pattern matcher enables search/replace within an FX graph.
The main entrypoint to the pattern matcher is register_replacement(). Given a
search function and a replacement function this will register a replacement with
a pass (such as torch._inductor.fx_passes.joint_graph.patterns).
Internally the pattern matcher represents patterns as a graph (a DAG). Creating
new patterns manually as a graph is cumbersome and error-prone so the standard
way to create patterns (using register_replacement()) is to provide a search
function and a replacement function which is traced and converted into a graph.
Because the search functions are built somewhat generic (they tend to ignore
tensor sizes, for example) register_replacement() allows you to specify an
`extra_check` function which performs additional checks to verify that the
matched pattern fully matches before returning it.
## Precompiled Patterns
New patterns are added using register_replacement(). Patterns added in this way
can have a compile-time overhead because they need to be traced before
use. Patterns can be precompiled and added using gen_register_replacement()
instead. To do this you call gen_register_replacement() instead of
register_replacement(). The arguments are the same except for an additional
unique name which is used as a lookup key.
## Internals
The match DAG is represented by a graph of `PatternExpr` nodes. Each PatternExpr
implements a `_match` method which returns either a `Match` object for a
successful match or a `FailedMatch` object for a failure to match.
"""
from __future__ import annotations
import contextlib
import dataclasses
import functools
import importlib
import inspect
import itertools
import logging
import operator
import os
import re
import textwrap
import typing
from abc import ABC, abstractmethod
from collections import defaultdict
from pathlib import Path
from typing import (
Any,
Callable,
DefaultDict,
Dict,
Generator,
Iterable,
List,
Mapping,
NoReturn,
Optional,
Protocol,
Sequence,
Tuple,
Type,
TypeVar,
Union,
)
from typing_extensions import Self, TypeIs
import torch
import torch._guards
import torch.fx
import torch.utils._pytree as pytree
from torch._dispatch.python import enable_python_dispatcher
from torch._dynamo.utils import counters
from torch._prims_common import is_integer_dtype
from torch._subclasses.fake_tensor import unset_fake_temporarily
from torch.fx.experimental.proxy_tensor import make_fx
from torch.fx.experimental.symbolic_shapes import guard_size_oblivious
from torch.fx.graph_module import _get_attr
from torch.fx.immutable_collections import immutable_dict, immutable_list
from torch.fx.passes.graph_transform_observer import GraphTransformObserver
from torch.utils._ordered_set import OrderedSet
from .._functorch import config as functorch_config
from .._functorch.aot_autograd import aot_function, make_boxed_func
from .._functorch.partitioners import default_partition
from .._subclasses import FakeTensor, FakeTensorMode
from ..fx import Transformer
from . import config
from .decomposition import select_decomp_table
from .lowering import fallback_node_due_to_unsupported_type
log = logging.getLogger(__name__)
aten = torch.ops.aten
prims = torch.ops.prims
Constant = Any
NodeOrConstant = Union[Constant, torch.fx.Node]
class SearchFn(Protocol):
__name__: str
def __call__(self, *args: Any, **kwargs: Any) -> Any:
...
class ReplaceFn(Protocol):
def __call__(self, *args: Any, **kwargs: Any) -> Any:
...
class TraceFn(Protocol):
def __call__(
self, fn: Union[SearchFn, ReplaceFn], *args: Any, **kwargs: Any
) -> torch.fx.GraphModule:
...
T = TypeVar("T")
# What's a better name for this?
FnsType = Union[torch.fx.node.Target, str]
class Multiple:
def __init__(self) -> None:
# Ensure we're really a singleton.
assert "MULTIPLE" not in globals() or self is MULTIPLE
# Sentinel indicating multiple quantities can be matched
MULTIPLE = Multiple()
def _transfer_meta(new_meta: Dict[str, Any], old_meta: Dict[str, Any]) -> None:
# transfer metadata after pattern matching occurs.
# skip "val" and "tensor_meta" because this info is too specific; it's unlikely
# to remain accurate after pattern matching has occurred.
new_meta.update(
(k, v) for k, v in old_meta.items() if k in torch.fx.proxy._COPY_META_FIELDS
)
class Match:
"""
Represents a successfully matched pattern.
The `Match` object is returned to represent a successfully matched
pattern. Included in the Match are the pattern that was matched, the graph
nodes matched, and any args that were used during the matching.
The args and kwargs are specific to the type of pattern that was matched and
provide hints about what was matched.
"""
pattern: PatternExpr
args: List[Any]
kwargs: Dict[str, Any]
nodes: List[torch.fx.Node]
targets: Dict[_TargetExpr, torch.fx.node.Target]
ctx: MatchContext
replacement_graph: Optional[torch.fx.GraphModule]
def __init__(
self,
ctx: MatchContext,
pattern: PatternExpr,
args: Optional[Sequence[Any]] = None,
kwargs: Optional[Dict[str, Any]] = None,
) -> None:
super().__init__()
self.pattern = pattern
# The input nodes that must be passed in to the result
self.args = list(args or [])
self.kwargs = kwargs or {}
# The nodes matched in this expression
self.nodes = []
# Mapping CallFunction to the node.target
self.targets = {}
self.ctx = ctx
self.replacement_graph = None
@property
def graph(self) -> torch.fx.Graph:
return self.ctx.graph
def extend(self, other: Match) -> None:
if self.kwargs:
for key in OrderedSet(self.kwargs.keys()) & OrderedSet(other.kwargs.keys()):
if self.kwargs[key] != other.kwargs[key]:
raise FailedMatch("kwarg mismatch: {}", key)
self.args.extend(other.args)
self.nodes.extend(other.nodes)
self.kwargs.update(other.kwargs)
self.targets.update(other.targets)
def bundle(self) -> Match:
# Wrap args in an extra list
self.args = [tuple(self.args)] if self.args else []
return self
def __repr__(self) -> str:
return f"Match(..., {self.args}, {self.kwargs})"
def erase_nodes(self) -> None:
graph = self.graph
for n in reversed(self.nodes):
if not n._erased and not n.users:
graph.erase_node(n)
def output_nodes(self) -> List[Optional[torch.fx.Node]]:
return [
(self.ctx.pattern_to_node[p] if p is not None else None)
for p in self.ctx.outputs
]
def output_node(self) -> torch.fx.Node:
return next(p for p in self.output_nodes() if p)
def replace_with_graph(
self, replacement_graph: torch.fx.Graph, args: Sequence[Any]
) -> None:
ReplacementPatternEntry.replace_with_graph(
self, self.ctx.graph, replacement_graph, args
)
def replace_by_example(
self,
replacement_fn: ReplaceFn,
args: Sequence[Any],
trace_fn: Optional[TraceFn] = None,
run_functional_passes: bool = True,
) -> None:
"""Replace with a graph generated by tracing the replacement_fn.
Args:
run_functional_passes (bool). If we should run passes that
assume functional IR (like DCE, remove_noop_ops), on the
replacement graph.
"""
from torch._inductor.virtualized import NullHandler, V
context = (
V.fake_mode
if (not isinstance(V.fake_mode, NullHandler) or (V.fake_mode is None))
else contextlib.nullcontext()
)
with context:
if trace_fn is None:
trace_fn = functools.partial(
fwd_only, run_functional_passes=run_functional_passes
)
replacement = trace_fn(
replacement_fn, torch.fx.map_arg(args, lambda arg: arg.meta["val"]) # type: ignore[arg-type]
)
if len(self.nodes) == 1:
for n in replacement.graph.nodes:
_transfer_meta(new_meta=n.meta, old_meta=self.nodes[0].meta)
ReplacementPatternEntry.replace_with_graph(
self,
self.ctx.graph,
replacement,
args,
)
class FailedMatch(RuntimeError):
"""
Represents a unsuccessful match.
The `FailedMatch` object is returned to represent a failure to match a
pattern.
"""
format_string: str
def __init__(self, format_string: str, *args: Any, **kwargs: Any) -> None:
self.format_string = format_string
# We want to construct error messages lazily instead of eagerly, as
# constructing them eagerly can significantly worsen compile times.
if len(format_string) > 200:
raise RuntimeError(
f"Format string too long - use lazy construction of strings instead. Format string is\n {format_string}"
)
self.args = args
self.kwargs = kwargs
def __str__(self) -> str:
return self.format_string.format(*self.args, **self.kwargs)
def __bool__(self) -> bool:
return False
MatchResult = Union[Match, FailedMatch]
def is_match(m: MatchResult) -> TypeIs[Match]:
"""
TypeIs cannot act on `self`. Thus this function exists to let mypy
recognize FailedMatch.__bool__ as a TypeIs.
"""
return bool(m)
class MatchContext:
"""
Internal state needed while running PatternExpr._match().
"""
outputs: List[Optional[PatternExpr]]
pattern_to_node: Dict[PatternExpr, Optional[torch.fx.Node]]
graph: torch.fx.Graph
exclusive_node_set: List[NodeOrConstant]
def __init__(
self,
outputs: List[Optional[PatternExpr]],
pattern_to_node: Optional[Dict[PatternExpr, torch.fx.Node]] = None,
*,
graph: torch.fx.Graph,
) -> None:
self.outputs = outputs
self.pattern_to_node = {} if pattern_to_node is None else dict(pattern_to_node)
self.graph = graph
self.exclusive_node_set = []
def match(self, pattern: PatternExpr, node: NodeOrConstant) -> MatchResult:
"""wrapper to check reused nodes in patterns"""
if pattern in self.pattern_to_node:
if self.pattern_to_node[pattern] == node:
return Match(self, pattern) # already checked this node
else:
return FailedMatch("repeated pattern differs")
m = pattern._match(node, self)
assert pattern not in self.pattern_to_node
self.pattern_to_node[pattern] = node if m else None
return m
def filter_multi_user_patterns(self) -> Dict[PatternExpr, torch.fx.Node]:
return {
pattern: node
for pattern, node in self.pattern_to_node.items()
if pattern.has_multiple_users() and node is not None
}
class PatternExpr(ABC):
"""
Base class for types of patterns.
"""
@abstractmethod
def _match(self, node: torch.fx.Node, ctx: MatchContext) -> MatchResult:
...
def match(self, node: torch.fx.Node) -> MatchResult:
try:
return MatchContext([self], graph=node.graph).match(self, node)
except FailedMatch as e:
return e
def has_multiple_users(self) -> bool:
return False
def __repr__(self) -> str:
return self.__class__.__name__ + "()"
def find_anchor_nodes(
self, ctx: MatchContext, searched: OrderedSet[torch.fx.Node]
) -> Generator[Optional[torch.fx.Node], None, None]:
if self in ctx.pattern_to_node:
yield ctx.pattern_to_node[self]
def pattern_eq(self, other: Any) -> bool:
"""
Compare two `PatternExpr`s and return true if they are the
same. Note this is NOT matching a pattern - it is comparing the pattern
structures (for debugging).
"""
return isinstance(other, self.__class__)
class Arg(PatternExpr):
"""
Capture an arg which will become an input to the handler. Args are
passed in depth first order.
"""
def _match(self, node: NodeOrConstant, ctx: MatchContext) -> MatchResult:
return Match(ctx, self, args=[node]) # matches anything
class Ignored(PatternExpr):
"""
Match an arg, but don't pass it to handler
"""
def _match(self, node: NodeOrConstant, ctx: MatchContext) -> MatchResult:
return Match(ctx, self) # matches anything
def __repr__(self) -> str:
return "*"
def pretty_print(self, pp: PatternPrettyPrinter) -> str:
return "Ignored()"
class KeywordArg(PatternExpr):
"""
Capture a kwarg which will become an input to the handler.
"""
def __init__(self, name: str) -> None:
super().__init__()
self.name = name
def __repr__(self) -> str:
return f"KeywordArg({self.name!r})"
def _match(self, node: NodeOrConstant, ctx: MatchContext) -> MatchResult:
return Match(ctx, self, kwargs={self.name: node}) # matches anything
def pattern_eq(self, other: Any) -> bool:
other = typing.cast(Self, other) # super makes sure this is true
return super().pattern_eq(other) and self.name == other.name
class ExclusiveKeywordArg(PatternExpr):
"""
Capture a kwarg which will become an input to the handler.
"""
name: str
def __init__(self, name: str) -> None:
super().__init__()
self.name = name
def __repr__(self) -> str:
return f"ExclusiveKeywordArg({self.name!r})"
def _match(self, node: NodeOrConstant, ctx: MatchContext) -> MatchResult:
if node in ctx.exclusive_node_set:
return FailedMatch("exclusive arg appears twice")
ctx.exclusive_node_set.append(node)
return Match(ctx, self, kwargs={self.name: node}) # matches anything
def pattern_eq(self, other: Any) -> bool:
other = typing.cast(Self, other) # super makes sure this is true
return super().pattern_eq(other) and self.name == other.name
class _TargetExpr(PatternExpr):
"""
Base class for filtering match by node.target
"""
fns: List[FnsType]
fns_set: OrderedSet[FnsType]
def __init__(
self, fns: Union[FnsType, Sequence[FnsType]], users: Union[Multiple, int] = 1
) -> None:
super().__init__()
fns = [fns] if callable(fns) or isinstance(fns, str) else list(fns)
for fn in fns:
if isinstance(fn, torch._ops.OpOverloadPacket):
fns.extend(getattr(fn, overload) for overload in fn.overloads())
self.fns = fns
self.fns_set = OrderedSet(fns)
self.users = users
@property
@abstractmethod
def op(self) -> str:
...
def fns_repr(self) -> str:
first_repr = self.fns[0]
if not isinstance(first_repr, str):
first_repr = first_repr.__name__
if len(self.fns) > 1:
return f"[{first_repr}, ...]"
elif self.fns[0] is getattr(torch, first_repr, None):
return f"torch.{first_repr}"
elif isinstance(self.fns[0], torch._ops.OpOverload):
return str(self.fns[0])
else:
return first_repr
def __repr__(self) -> str:
if self.users is MULTIPLE:
comma_users = ", MULTIPLE"
elif self.users != 1:
comma_users = f", {self.users})"
else:
comma_users = ""
return f"{self.__class__.__name__}({self.fns_repr()}{comma_users})"
def has_multiple_users(self) -> bool:
return isinstance(self.users, Multiple) or self.users > 1
def find_anchor_nodes(
self, ctx: MatchContext, searched: OrderedSet[torch.fx.Node]
) -> Generator[Optional[torch.fx.Node], None, None]:
raise NotImplementedError
def _match_fns(self, node: torch.fx.Node) -> bool:
return (
isinstance(node, torch.fx.Node)
and node.op == self.op
and extract_target(node) in self.fns_set
)
def _match_users(self, node: torch.fx.Node, ctx: MatchContext) -> bool:
return (
self in ctx.outputs
or self.users is MULTIPLE
or len(node.users) == self.users
)
def pattern_eq(self, other: Any) -> bool:
other = typing.cast(Self, other) # super makes sure this is true
return (
super().pattern_eq(other)
and self.op == other.op
and self.fns == other.fns
and self.users == other.users
)
_SimpleSpec = Tuple[Any, ...]
class _TargetArgsExpr(_TargetExpr):
"""
Base class for filtering match by node.{target,args,kwargs}
"""
def __init__(
self,
fns: Union[torch.fx.node.Target, str, Sequence[Any]],
*args: Any,
_users: Union[int, Multiple] = 1,
**kwargs: Any,
) -> None:
super().__init__(fns, _users)
self.args = tuple(args)
self.kwargs = dict(kwargs)
if any(
isinstance(x, (dict, list, tuple))
for x in itertools.chain(args, kwargs.values())
):
self.flatten = self.pytree_flatten
else:
self.flatten = self.simple_flatten
self.flat_args_kwargs = self.flatten(self.args, self.kwargs)
@staticmethod
def simple_flatten(
args: Sequence[Any], kwargs: Mapping[Any, Any]
) -> Tuple[Sequence[Any], Union[_SimpleSpec, pytree.TreeSpec]]:
values = (*args, *kwargs.values())
spec = (len(args), *kwargs.keys())
return values, spec
@staticmethod
def pytree_flatten(
args: Sequence[Any], kwargs: Mapping[Any, Any]
) -> Tuple[Sequence[Any], Union[_SimpleSpec, pytree.TreeSpec]]:
type_mapping = {immutable_list: tuple, list: tuple, immutable_dict: dict}
def convert_type(x: Any) -> Any:
cls = type(x)
convert_fn = type_mapping.get(cls)
if convert_fn is not None:
return pytree.tree_map(
convert_type,
convert_fn(x),
is_leaf=lambda x: type(x) in type_mapping,
)
return x
normalized_args_tree = pytree.tree_map(
convert_type,
(args, kwargs),
is_leaf=lambda x: type(x) in type_mapping,
)
flat, spec = pytree.tree_flatten(normalized_args_tree)
return flat, spec
def __repr__(self) -> str:
args = [
self.fns_repr(),
*map(repr, self.args),
*[f"{k}={v}" for k, v in self.kwargs.items()],
]
if self.users is MULTIPLE:
args.append("_users=MULTIPLE")
elif self.users != 1:
args.append(f"_users={self.users}")
return f"{self.__class__.__name__}({', '.join(args)})"
def pretty_print(self, pp: PatternPrettyPrinter) -> str:
args = [
self.fns_repr(),
*(pp.pretty_print(x) for x in self.args),
*[f"{k}={pp.pretty_print(v)}" for k, v in self.kwargs.items()],
]
if self.users is MULTIPLE:
args.append("_users=MULTIPLE")
elif self.users != 1:
args.append(f"_users={self.users}")
joiner_str = ", "
return f"{self.__class__.__name__}({joiner_str.join(args)})"
def _match(self, node: torch.fx.Node, ctx: MatchContext) -> MatchResult:
if not self._match_fns(node) or len(node.args) != len(self.args):
return FailedMatch("function_mismatch: node={}, pattern={}", node, self)
if not self._match_users(node, ctx):
return FailedMatch("multiple_users {}", self)
_args = node.args
_kwargs = node.kwargs
if len(_kwargs) < len(self.kwargs):
from torch.fx.operator_schemas import normalize_function
normalized_args_and_kwargs = normalize_function(
node.target, node.args, node.kwargs # type: ignore[arg-type]
)
if normalized_args_and_kwargs is None:
return FailedMatch("function_mismatch: node={}, pattern={}", node, self)
else:
_args, _kwargs = normalized_args_and_kwargs
if len(_args) == len(self.args) and len(_kwargs) >= len(self.kwargs):
_kwargs = {i: _kwargs[i] for i in _kwargs if i in self.kwargs}
else:
return FailedMatch(
"function_mismatch: node={}, pattern={}", node, self
)
else:
_kwargs = {i: _kwargs[i] for i in _kwargs if i in self.kwargs}
node_items, node_spec = self.flatten(_args, _kwargs)
self_items, self_spec = self.flat_args_kwargs
if node_spec != self_spec:
return FailedMatch("args_structure {} {}", node_spec, self_spec)
assert len(node_items) == len(self_items)
m = Match(ctx, self)
for i, pattern, child_node in zip(itertools.count(), self_items, node_items):
if isinstance(pattern, PatternExpr):
child_match = ctx.match(pattern, child_node)
if not is_match(child_match):
return child_match
m.extend(child_match)
elif isinstance(child_node, torch.fx.Node) or child_node != pattern:
return FailedMatch(
"constant_args: {} {!r}!={pattern!r}", node, child_node
)
m.nodes.append(node)
m.targets[self] = node.target
return m
def find_anchor_nodes(
self, ctx: MatchContext, searched: OrderedSet[torch.fx.Node]
) -> Generator[Optional[torch.fx.Node], None, None]:
"""
This is used when we are matching a pattern with multiple outputs.
There is a partial match (stored in ctx) and we want to walk
this pattern to find a connection to an already-matched node.
Yields candidate nodes that `self._match` might like.
"""
if self in ctx.pattern_to_node:
yield ctx.pattern_to_node[self]
return
for pattern in self.flat_args_kwargs[0]:
if isinstance(pattern, PatternExpr):
for other_node in pattern.find_anchor_nodes(ctx, searched):
if not isinstance(other_node, torch.fx.Node):
continue
for node in other_node.users:
if node not in searched:
if self._match_fns(node):
yield node
searched.add(node)
def pattern_eq(self, other: Any) -> bool:
other = typing.cast(Self, other) # super makes sure this is true
return (
super().pattern_eq(other)
and self.flat_args_kwargs[1] == other.flat_args_kwargs[1]
and all(
a.pattern_eq(b) if isinstance(a, PatternExpr) else a == b
for a, b in zip(self.flat_args_kwargs[0], other.flat_args_kwargs[0])
)
)
class CallFunction(_TargetArgsExpr):
"""
Matches a call_function node in the FX graphs: `fns[i](*args, **kwargs)`
"""
op = "call_function"
class CallMethod(_TargetArgsExpr):
"""
Matches a call_method node in the FX graphs: `fns[i].method(*args, **kwargs)`
"""
op = "call_method"
class CallModule(_TargetArgsExpr):
"""
Matches a call_module node in the FX graphs: `module(*args, **kwargs)`
"""
op = "call_module"
class _TargetExprVarArgs(_TargetExpr):
"""
Matches a call_function node with any arguments which are passed into the pattern
"""
def _match(self, node: torch.fx.Node, ctx: MatchContext) -> MatchResult:
if not self._match_fns(node):
return FailedMatch("function_mismatch")
if not self._match_users(node, ctx):
return FailedMatch("multiple_users")
m = Match(ctx, self)
m.nodes.append(node)
m.targets[self] = node.target
m.args.extend(node.args)
m.kwargs.update(node.kwargs)
return m
class CallFunctionVarArgs(_TargetExprVarArgs):
op = "call_function"
class CallMethodVarArgs(_TargetExprVarArgs):
op = "call_method"
class CallModuleVarArgs(_TargetExprVarArgs):
op = "call_module"
class ListOf(PatternExpr):
"""
Matches a repeated pattern
"""
def __init__(self, pattern: PatternExpr, partial: bool = False) -> None:
super().__init__()
assert isinstance(pattern, PatternExpr)
self.pattern = pattern
self.partial = partial
def __repr__(self) -> str:
return f"{self.__class__.__name__}({self.pattern})"
def _match(self, node: List[torch.fx.Node], ctx: MatchContext) -> MatchResult: # type: ignore[override]
if not isinstance(node, (list, tuple)) or len(node) == 0:
return FailedMatch("non_list")
m = Match(ctx, self)
# Propagating patterns with multiple users will ensure we don't revisit
# the same nodes
pattern_to_node = ctx.filter_multi_user_patterns()
matched = False
for i, child_node in enumerate(node):
child_ctx = MatchContext(
ctx.outputs, pattern_to_node, graph=child_node.graph
)
child_match = child_ctx.match(self.pattern, child_node)
pattern_to_node = child_ctx.filter_multi_user_patterns()
if not is_match(child_match):
if not self.partial:
return FailedMatch("list[{}]: {}", i, child_match)
continue
matched = True
m.extend(child_match.bundle())
if not matched:
return FailedMatch("list: no_match")
return m.bundle()
def pattern_eq(self, other: Any) -> bool:
other = typing.cast(Self, other) # super makes sure this is true
return (
super().pattern_eq(other)
and self.pattern.pattern_eq(other.pattern)
and self.partial == other.partial
)
class MultiOutputPattern(PatternExpr):
outputs: List[Optional[PatternExpr]]
def __init__(self, outputs: Sequence[Optional[PatternExpr]]) -> None:
super().__init__()
assert isinstance(outputs[0], _TargetExpr)
assert all(x is None or isinstance(x, PatternExpr) for x in outputs), outputs
self.outputs = list(outputs)
self.op = outputs[0].op
@property
def fns(self) -> Union[Callable[..., Any], str, Sequence[Any]]:
# This cast is checked above in __init__()
output = typing.cast(_TargetExpr, self.outputs[0])
return output.fns
def __repr__(self) -> str:
return f"{self.__class__.__name__}({self.outputs})"
def pretty_print(self, pp: PatternPrettyPrinter) -> str:
args = [pp.pretty_print(x) for x in self.outputs]
joiner_str = f",\n{' '}"
str_out = f"{self.__class__.__name__}([{joiner_str.join(args)}"
str_out = f"{str_out}\n])"
return str_out
def _match(self, node: torch.fx.Node, ctx: MatchContext) -> MatchResult:
output = typing.cast(_TargetExpr, self.outputs[0])
m = ctx.match(output, node)
if not is_match(m):
return m
for pattern in self.outputs[1:]:
if pattern is None:
continue
child_match = self._match_from_anchors(pattern, ctx)
if not is_match(child_match):
return child_match
m.extend(child_match)
return m
def _match_from_anchors(
self, pattern: PatternExpr, ctx: MatchContext
) -> MatchResult:
prior = dict(ctx.pattern_to_node)
m: MatchResult = FailedMatch("no anchor found")
for node in pattern.find_anchor_nodes(ctx, OrderedSet()):
m = ctx.match(pattern, node)
if is_match(m):
return m
# revert any partial matches
ctx.pattern_to_node = dict(prior)
return m
def match(self, node: torch.fx.Node) -> MatchResult:
try:
return MatchContext(self.outputs, graph=node.graph).match(self, node)
except FailedMatch as e:
return e
def pattern_eq(self, other: Any) -> bool:
other = typing.cast(Self, other) # super makes sure this is true
return (
super().pattern_eq(other)
and len(self.outputs) == len(other.outputs)
and all(
a.pattern_eq(b) if isinstance(a, PatternExpr) else a == b
for a, b in zip(self.outputs, other.outputs)
)
)
class RepeatedExpr(PatternExpr):
"""
Checks for a repeated pattern. Useful for repeated operations after a node such as `split` or `unbind`
"""
def __init__(self, inner_pattern: _TargetExpr) -> None:
super().__init__()
self.inner_pattern = inner_pattern
self.op = inner_pattern.op
@property
def fns(self) -> Sequence[FnsType]:
return self.inner_pattern.fns
def _match(self, node: torch.fx.Node, ctx: MatchContext) -> MatchResult:
m = ctx.match(self.inner_pattern, node)
if not is_match(m):
return m
ctx.pattern_to_node.pop(
self.inner_pattern,
)
# Check all anchor nodes match the pattern
for anchor_node in self.inner_pattern.find_anchor_nodes(ctx, OrderedSet()):
anchor_m = MatchContext([self], graph=node.graph).match(
self.inner_pattern, anchor_node
)
if not is_match(anchor_m):
return anchor_m
m.extend(anchor_m)
return m
def pattern_eq(self, other: Any) -> bool:
other = typing.cast(Self, other) # super makes sure this is true
return super().pattern_eq(other) and self.inner_pattern.pattern_eq(
other.inner_pattern
)
class PatternPrettyPrinter:
"""
Serializes Patterns to executable python.
XXX: currently only used and tested for fuse attention patterns. May not cover
all patterns.
"""
def __init__(self) -> None:
self.namespace = torch.fx.graph._Namespace()
self.memoized_objs_names: Dict[PatternExpr, str] = {}
self.memoized_objs_pp: Dict[PatternExpr, str] = {}
@staticmethod
@functools.lru_cache(None)
def run(obj: PatternExpr, output_name: str = "output") -> str:
"""
Serializes obj to python code with obj written out to `output_name`
"""
pp = PatternPrettyPrinter()
assert hasattr(obj, "pretty_print")
out_str = obj.pretty_print(pp=pp)
output = [
f"{pp.memoized_objs_names[key]} = {pp.memoized_objs_pp[key]}"
for key in pp.memoized_objs_names
]
output.append(f"{output_name} = {out_str}")
return "\n".join(output)
def pretty_print(self, obj: Any) -> str:
if isinstance(obj, _TargetArgsExpr):
if memoized_name := self.memoized_objs_names.get(obj):
return memoized_name
else:
return self.memoize(obj)
if hasattr(obj, "pretty_print"):
return obj.pretty_print(self)
return repr(obj)
def memoize(self, obj: _TargetArgsExpr) -> str:
obj_str = obj.pretty_print(self)
obj_name = obj.fns_repr()
for prefix in ("aten.", "torch.", "prims."):
obj_name = obj_name.replace(prefix, "")
tmp_name = self.namespace.create_name(obj_name, None)
self.memoized_objs_names[obj] = tmp_name
self.memoized_objs_pp[obj] = obj_str
return tmp_name
class _PassDictsType(Protocol):
def __getitem__(self, k: Tuple[str, torch.fx.node.Target]) -> List[PatternEntry]:
...
@dataclasses.dataclass
class PatternEntry:
pattern: PatternExpr
extra_check: Callable[[Match], bool]
def apply(self, match: Match, graph: torch.fx.Graph, node: torch.fx.Node) -> None:
raise NotImplementedError
def register(
self,
pass_dicts: Union[_PassDictsType, Sequence[_PassDictsType]],
target: Union[torch.fx.node.Target, None] = None,
prepend: bool = False,
) -> None:
if target is None:
assert hasattr(self.pattern, "fns")
for fn in self.pattern.fns:
self.register(pass_dicts, fn, prepend=prepend)
elif isinstance(pass_dicts, (dict, PatternMatcherPass)):
assert hasattr(self.pattern, "op")
if prepend:
pass_dicts[(self.pattern.op, target)].insert(0, self)
else:
pass_dicts[(self.pattern.op, target)].append(self)
else:
pass_dicts = typing.cast(Sequence[_PassDictsType], pass_dicts)
for x in pass_dicts:
self.register(x, target, prepend=prepend)
@dataclasses.dataclass
class LoweringPatternEntry(PatternEntry):
handler: Callable[..., Any]
def apply(self, match: Match, graph: torch.fx.Graph, node: torch.fx.Node) -> None:
handler = functools.wraps(self.handler)(functools.partial(self.handler, match))
with graph.inserting_before(node):
replacement = graph.call_function(handler, tuple(match.args), match.kwargs)
replacement.meta.update(node.meta)
node.replace_all_uses_with(replacement)
assert match.nodes[-1] is node
match.erase_nodes()
@dataclasses.dataclass
class GraphPatternEntry(PatternEntry):
"""
A pattern that runs a function on the FX graph
"""
handler: Callable[..., Any]
def apply(self, match: Match, graph: torch.fx.Graph, node: torch.fx.Node) -> None:
with graph.inserting_before(node):
self.handler(match, *match.args, **match.kwargs)
@dataclasses.dataclass
class ReplacementPatternEntry(PatternEntry):
normalize_args: Callable[..., List[Any]]
@staticmethod
def replace_with_graph(
match: Match,
graph: torch.fx.Graph,
replacement_graph: Union[torch.fx.Graph, torch.fx.GraphModule],
args: Sequence[torch.fx.Node],
) -> None:
class Replacer(torch.fx.Interpreter):
call_method = None # type: ignore[assignment]
call_module = None # type: ignore[assignment]
get_attr = None # type: ignore[assignment]
def run_node(self, node: torch.fx.Node) -> Any:
if node.op in ("placeholder", "output"):
return super().run_node(node)
if node.op == "call_function":
target = node.target
args, kwargs = self.fetch_args_kwargs_from_env(node)
result = graph.call_function(target, args, kwargs) # type: ignore[arg-type]
_transfer_meta(new_meta=result.meta, old_meta=node.meta)
if "val" in node.meta and "val" not in result.meta:
result.meta["val"] = node.meta["val"]
if isinstance(node.meta["val"], torch.Tensor):
assert "tensor_meta" in node.meta
result.meta["tensor_meta"] = node.meta["tensor_meta"]
return result
raise NotImplementedError(f"unhandled {node}")
output_nodes = match.output_nodes()
if len(output_nodes) == 1:
last_node = output_nodes[0]
else:
assert output_nodes[0]
nodes = list(output_nodes[0].graph.nodes)
indices = [
(nodes.index(n), n)
for n in output_nodes
if isinstance(n, torch.fx.Node)
]
last_node = min(indices, key=operator.itemgetter(0))[1]
def percolate_tags(
node: torch.fx.Node,
tag_name: str,
tag_value: str,
input_stops: OrderedSet[torch.fx.Node],
) -> None:
queue = [node]
visited = OrderedSet[torch.fx.Node]()
while queue:
arg = queue.pop()
if (
arg not in visited
and arg not in input_stops
and hasattr(arg, "meta")
):
visited.add(arg)
arg.meta[tag_name] = tag_value
queue.extend(arg.all_input_nodes)
with graph.inserting_before(last_node):
replacement = Replacer(replacement_graph).run(*args) # type: ignore[arg-type]
if isinstance(replacement, torch.fx.Node):
replacement = [replacement]
def maybe_getitem(node: torch.fx.Node) -> Any:
if node.op != "call_function":
return None
if node.target != operator.getitem:
return None
assert len(node.args) == 2
return node.args[1]
def replace(
old: Union[torch.fx.Node, None],
new: Union[torch.fx.Node, Sequence[torch.fx.Node], None],
) -> None:
if old is None:
assert new is None
return
assert isinstance(old, torch.fx.Node)
if new is None:
old.replace_all_uses_with(None) # type: ignore[arg-type]
graph.erase_node(old)
return
if isinstance(new, torch.fx.Node):
if "val" not in new.meta:
new.meta.update(old.meta)
# Preserve the recompute tags in the replacement graph. We
# look at the recompute tags of the original output node to
# propagate the tag from the output all the way to the input
# args (named as args in the replace_with_graph).
# Note that this is best effort. Since patterns are from
# many to many, there is no easy way to correctly map the
# recomputable tags. It is possible in some scenarios that we
# incorrectly tag some nodes as recomputables.
for tag_name in ["recompute", "ac_graph_id"]:
if tag_name in old.meta:
percolate_tags(
new, tag_name, old.meta[tag_name], OrderedSet(args)
)
old.replace_all_uses_with(new)
graph.erase_node(old)
return
# `new` is not a node: it's a list of nodes.
#
# This happens when we want to replace a node that has a single
# packed return with multiple unpacked returns. We need to do
# some graph surgery here.
#
# Example:
# def original_graph(x):
# a = op(x)
# b = a[0]
# c = a[1]
# ...
#
# Assume that we want to replace op(x) with the graph
# def new_op(x):
# w = x + 1
# z = x + 2
# return (w, z)
#
# We need to replace `op` with the contents of `new_op`,
# and then rewrite a[0] to be w and a[1] to be z, as so:
# def new_graph(x):
# w = x + 1
# z = x + 2
# b = w
# c = z
# ...
old_uses = list(old.users.keys())
for user in old_uses:
idx = maybe_getitem(user)
if idx is None:
raise AssertionError("can't handle")
replace(user, new[idx]) # type: ignore[index]
graph.erase_node(old)
if len(output_nodes) == len(replacement):
for old, new in zip(output_nodes, replacement):
replace(old, new)
else:
assert len(output_nodes) == 1
replace(output_nodes[0], replacement)
match.erase_nodes()
def apply(self, match: Match, graph: torch.fx.Graph, node: torch.fx.Node) -> None:
assert match.replacement_graph is not None
self.replace_with_graph(
match,
graph,
match.replacement_graph,
self.normalize_args(*match.args, **match.kwargs),
)
def _return_true(match: Match) -> bool:
return True
def log_trace_failure(search_fn: Callable[..., Any], e: RuntimeError) -> None:
log.info(
"Replacement pattern %s failed to apply due to shape mismatch: %s",
search_fn.__name__,
e,
)
def register_replacement(
search_fn: SearchFn,
replace_fn: ReplaceFn,
example_inputs: Iterable[Any],
trace_fn: TraceFn,
pass_dicts: Union[_PassDictsType, Sequence[_PassDictsType]],
extra_check: Callable[[Match], bool] = _return_true,
scalar_workaround: Union[Dict[str, Union[float, int]], None] = None,
exclusive_arg_names: Sequence[str] = (),
search_fn_pattern: Union[PatternExpr, None] = None,
) -> bool:
"""
Create a replacement rule based on example functions that get traced
to create patterns. This supports both training and inference when
run on a joint forward+backward graph.
Args:
search_fn: traced to give original pattern
replace_fn: traced to give replacement graph
example_inputs: example inputs for initial trace
trace_fn: fwd_only or joint_fwd_bwd
pass_dict: dict of passes to register to
extra_check: additional check to run on match(using real shapes)
"""
argnames_static = [*inspect.signature(search_fn).parameters.keys()]
def check_fn(match: Match) -> bool:
"""
Often shapes get burned into the pattern, so our initial match ran with
`ignore_types=(int, ...)`.
Recheck the match with the correct shapes.
"""
argnames = list(argnames_static)
for name in argnames:
if name not in match.kwargs:
raise RuntimeError(
f"Not all inputs to pattern found in match.kwargs. Perhaps one "
f"of the inputs is unused? argnames={argnames}, match.kwargs={match.kwargs}"
)
args = list(
torch.fx.map_arg( # type: ignore[arg-type]
[match.kwargs[name] for name in argnames], lambda n: n.meta["val"]
)
)
sym_args: List[torch.SymInt] = []
with torch._dynamo.utils.detect_fake_mode(args):
for i, grad in enumerate(requires_grad):
if isinstance(args[i], torch.Tensor):
if grad and is_integer_dtype(args[i].dtype):
return False
args[i] = torch.empty_strided(
args[i].size(),
args[i].stride(),
dtype=args[i].dtype,
device=args[i].device,
requires_grad=grad,
)
for v in itertools.chain(args[i].shape, args[i].stride()):
if isinstance(v, torch.SymInt) and all(
guard_size_oblivious(v != a) for a in sym_args
):
sym_args.append(v)
# If we were given a pre-traced pattern then use that instead of
# retracing. Note that this means the pattern has to be independent
# of its args.
specific_pattern = search_fn_pattern
if not specific_pattern:
if sym_args:
# AOT Autograd and make fx will dedupe symbolic shape size
# accesses of sym ints that appear as inputs
# We don't want the sym_size uses to interfere with pattern matching
# so we provide them as inputs.
# Later, when we actually do the replacement, the symbolic shape
# sizes will get re-traced and added to the graph.
def search_fn_new(*args_new: Any) -> Any:
return search_fn(*args_new[len(args_new) - len(args) :])
try:
specific_graph = trace_fn(search_fn_new, sym_args + args)
except RuntimeError as e:
log_trace_failure(search_fn, e)
return False
# correct argnames in the graph
sym_arg_names = []
for i, placeholder in zip(
range(len(sym_args) + len(args)),
specific_graph.graph.nodes,
):
if i < len(sym_args):
sym_arg_names.append(placeholder.target)
continue
with specific_graph.graph.inserting_after(placeholder):
new_node = specific_graph.graph.placeholder(
argnames[i - len(sym_args)]
)
new_node.target = new_node.name
placeholder.replace_all_uses_with(new_node)
specific_graph.graph.erase_node(placeholder)
argnames = sym_arg_names + argnames
else:
try:
specific_graph = trace_fn(search_fn, args)
except RuntimeError as e:
log_trace_failure(search_fn, e)
return False
specific_pattern = fx_to_pattern(
specific_graph,
argnames=argnames,
exclusive_arg_names=exclusive_arg_names,
scalar_workaround=scalar_workaround,
)
node = match.output_nodes()[0]
assert node is not None
specific_pattern_match = specific_pattern.match(node)
if is_match(specific_pattern_match) and extra_check(specific_pattern_match):
# trace the pattern using the shapes from the user program
match.replacement_graph = trace_fn(replace_fn, args)
if len(match.nodes) == 1:
for n in match.replacement_graph.graph.nodes:
_transfer_meta(
new_meta=n.meta,
old_meta=match.nodes[0].meta,
)
return True
return False
def normalize_args(**kwargs: Any) -> List[Any]:
args = [kwargs.pop(name) for name in argnames_static]
for i in range(1, len(kwargs) + 1):
if f"tangents_{i}" not in kwargs:
break
args.append(kwargs.pop(f"tangents_{i}"))
assert not kwargs, f"leftover kwargs: {kwargs!r}"
return args
if trace_fn is joint_fwd_bwd:
# If inference mode is enabled during compilation, assume that we don't
# want to match on any training graph patterns
if torch.is_inference_mode_enabled():
return False
# TODO: Revisit the functionalize_rng_ops for lowmem dropout
with functorch_config.patch(functionalize_rng_ops=False):
requires_grad: List[bool] = [
isinstance(x, torch.Tensor) and x.requires_grad for x in example_inputs
]
if search_fn_pattern is None:
pattern = gen_pattern(
search_fn,
example_inputs,
trace_fn,
scalar_workaround,
exclusive_arg_names,
)
else:
pattern = search_fn_pattern
pattern_repr = PatternPrettyPrinter.run(pattern)
assert pattern_repr not in _seen_patterns
_seen_patterns.add(pattern_repr)
pattern = ReplacementPatternEntry(
pattern=pattern,
extra_check=check_fn,
normalize_args=normalize_args,
)
pattern.register(pass_dicts)
return pattern.pattern
_serialized_patterns = OrderedSet[str]()
def _serialize_pattern(
unique_name: str,
search_fn: SearchFn,
example_inputs: Iterable[Any],
trace_fn: TraceFn,
scalar_workaround: Union[Dict[str, Union[float, int]], None],
) -> PatternExpr:
def get_file_template() -> str:
auto_generated_msg = textwrap.dedent(
"""\
# This is an auto-generated file. Please do not modify it by hand.
# To re-generate, run:
# cd ~/pytorch && python torchgen/fuse/gen_patterns.py
"""
)
file_template = textwrap.dedent(
"""\
# mypy: ignore-errors
# noqa: F401, E501
{msg}
import torch
import torch._inductor
aten = torch.ops.aten
prims = torch.ops.prims
"""
).format(msg=auto_generated_msg)
pattern_matcher_imports = []
for name in dir(torch._inductor.pattern_matcher):
attr = getattr(torch._inductor.pattern_matcher, name)
if isinstance(attr, type) and issubclass(attr, (PatternExpr, _TargetExpr)):
pattern_matcher_imports.append(name)
formatted_imports = ",\n ".join(pattern_matcher_imports)
formatted_imports = f"from torch._inductor.pattern_matcher import (\n {formatted_imports},\n)\n"
return f"{file_template}{formatted_imports}"
if not SERIALIZED_PATTERN_PATH.is_dir():
raise RuntimeError(
f"Could not find serialized patterns directory at {SERIALIZED_PATTERN_PATH}"
)
pattern_name = search_fn.__name__
from torch._functorch import config as functorch_config
with functorch_config.patch(functionalize_rng_ops=False):
pattern = gen_pattern(search_fn, example_inputs, trace_fn, scalar_workaround)
serialized_pattern = PatternPrettyPrinter.run(pattern, output_name=unique_name)
if pattern_name not in _serialized_patterns:
write_mode = "w"
_serialized_patterns.add(pattern_name)
else:
write_mode = "a"
file_template = get_file_template()
with open(SERIALIZED_PATTERN_PATH / f"{pattern_name}.py", write_mode) as f:
if write_mode == "w":
f.write(file_template)
else:
f.write("\n\n")
f.write(serialized_pattern)
f.write("\n")
return pattern
SERIALIZED_PATTERN_PATH = Path(__file__).parent / "fx_passes" / "serialized_patterns"
# This is the set of serialized patterns that we've registered. Used by
# test_serialized_patterns_up_to_date() to ensure the patterns are up
# to date.
_known_precompiled_patterns: List[
Tuple[
Any,
Iterable[Any],
Callable[[Callable[..., Any], Iterable[Any]], torch.fx.GraphModule],
Any,
PatternExpr,
]
] = []
def gen_register_replacement(
unique_name: str,
search_fn: SearchFn,
replace_fn: ReplaceFn,
example_inputs: Iterable[Any],
trace_fn: TraceFn,
pass_dicts: Union[_PassDictsType, Sequence[_PassDictsType]],
extra_check: Callable[[Match], bool] = _return_true,
scalar_workaround: Union[Dict[str, Union[float, int]], None] = None,
exclusive_arg_names: Sequence[str] = (),
skip_duplicates: bool = False,
) -> None:
# Make sure the example_inputs is materialized.
example_inputs = tuple(example_inputs)
if "PYTORCH_GEN_PATTERNS" in os.environ:
pat = _serialize_pattern(
unique_name, search_fn, example_inputs, trace_fn, scalar_workaround
)
else:
pattern_name = search_fn.__name__
m = importlib.import_module(
f"torch._inductor.fx_passes.serialized_patterns.{pattern_name}"
)
if not m or not hasattr(m, unique_name):
log.warning(
"Precompiled pattern %r not found. Run torchgen/fuse/gen_patterns.py.",
unique_name,
)
pat = getattr(m, unique_name)
for arg in pytree.tree_iter(example_inputs):
if isinstance(arg, FakeTensor) and arg.constant is not None:
# This can be a problem - small fake tensors (e.g. `tensor(2)`) will
# hold onto their original constant value - and by stashing it here
# will cause a memory leak if the constant value is on GPU.
# Since this is just an optimization we can clear it out.
arg.constant = None
if PatternPrettyPrinter.run(pat) in _seen_patterns and skip_duplicates:
return
_known_precompiled_patterns.append(
(search_fn, example_inputs, trace_fn, scalar_workaround, pat)
)
register_replacement(
search_fn,
replace_fn,
example_inputs,
trace_fn,
pass_dicts,
extra_check,
scalar_workaround,
exclusive_arg_names,
search_fn_pattern=pat,
)
@functorch_config.patch(functionalize_rng_ops=False)
def gen_pattern(
search_fn: SearchFn,
example_inputs: Sequence[Any],
trace_fn: TraceFn,
scalar_workaround: Union[Dict[str, Union[float, int]], None] = None,
exclusive_arg_names: Sequence[str] = (),
) -> PatternExpr:
argnames = [*inspect.signature(search_fn).parameters.keys()]
if scalar_workaround is None:
scalar_workaround = {}
flat_inputs = []
input_idx = 0 # Positional arguments index
for argname in argnames:
if argname in scalar_workaround:
flat_inputs.append(scalar_workaround[argname])
else:
flat_inputs.append(example_inputs[input_idx])
input_idx += 1
search_gm = trace_fn(search_fn, flat_inputs)
return fx_to_pattern(
search_gm,
ignore_types=(int, float, list, torch.device, torch.dtype),
argnames=argnames,
scalar_workaround=scalar_workaround,
exclusive_arg_names=exclusive_arg_names,
)
def register_lowering_pattern(
pattern: PatternExpr,
extra_check: Callable[[Match], bool] = _return_true,
*,
pass_dict: _PassDictsType,
prepend: bool = False,
) -> Callable[[Callable[..., Any]], Callable[..., Any]]:
"""
Register an aten to inductor IR replacement pattern. The decorated
function is saved and then called a lowering time allowing direct
pattern to inductor IR conversion.
"""
def decorator(handler: Callable[..., Any]) -> Callable[..., Any]:
assert callable(handler)
LoweringPatternEntry(
pattern=pattern, extra_check=extra_check, handler=handler
).register(pass_dict, prepend=prepend)
handler._inductor_lowering_function = True # type: ignore[attr-defined]
return handler
return decorator
def register_graph_pattern(
pattern: PatternExpr,
extra_check: Callable[[Match], bool] = _return_true,
*,
pass_dict: _PassDictsType,
prepend: bool = False,
) -> Callable[[Callable[..., Any]], Callable[..., Any]]:
"""
Register a pattern that runs a function on the FX graph, allowing
custom transformation code.
"""
def decorator(handler: Callable[..., Any]) -> Callable[..., Any]:
assert callable(handler)
GraphPatternEntry(
pattern=pattern, extra_check=extra_check, handler=handler
).register(pass_dict, prepend=prepend)
return handler
return decorator
def is_start_of_fx_graph(graph: torch.fx.Graph, node: torch.fx.Node) -> bool:
# first node in the graph
return node is next(iter(graph.nodes))
# match: copy_, relu_, _set_grad_enabled, manual_seed, _enter_autocast, etc
# doesn't match: __rshift__, etc
_mutation_op_re = re.compile(r"(?<!_)(_$|_[.]|(\b|_)(set|enter|exit|seed)(\b|_))(?!_)")
def fixme_incorrect_inductor_schema_op(op: torch._ops.OpOverload) -> bool:
if op.namespace != "inductor":
return False
# TODO - fix schema
# Dont add any more !
return op in (
torch.ops.inductor.accumulate_grad_.default,
torch.ops.inductor.resize_storage_bytes_.default,
)
def is_mutation_op(node: torch.fx.Node) -> bool:
if isinstance(
node.target, torch._ops.OpOverload
) and not fixme_incorrect_inductor_schema_op(node.target):
return node.target._schema.is_mutable
elif isinstance(
node.target, torch._higher_order_ops.auto_functionalize.AutoFunctionalized
):
return False
if node.op == "call_function":
if _mutation_op_re.search(node.target.__name__): # type: ignore[union-attr]
return True
elif node.op == "call_method":
if _mutation_op_re.search(node.target): # type: ignore[union-attr, arg-type]
return True
return node.kwargs.get("out") is not None
def same_mutation_regions(a: torch.fx.Node, b: torch.fx.Node) -> bool:
assert "mutation_region_id" in a.meta
assert "mutation_region_id" in b.meta
return a.meta["mutation_region_id"] == b.meta["mutation_region_id"]
def get_mutation_region_id(graph: torch.fx.Graph, node: torch.fx.Node) -> int:
n = node
while "mutation_region_id" not in n.meta and not is_start_of_fx_graph(graph, n):
n = n.prev
mutation_region_id = n.meta.get("mutation_region_id", 0)
while n is not node:
n = n.next
if is_mutation_op(n):
mutation_region_id += 1
n.meta["mutation_region_id"] = mutation_region_id
return mutation_region_id
def should_compute_mutation_region_ids(graph: torch.fx.GraphModule) -> bool:
return "mutation_region_id" not in next(iter(graph.nodes)).meta # type: ignore[arg-type]
def compute_mutation_region_ids(graph: torch.fx.GraphModule) -> None:
mutation_region_id = 0
for nd in graph.nodes: # type: ignore[union-attr]
if is_mutation_op(nd):
mutation_region_id += 1
nd.meta["mutation_region_id"] = mutation_region_id
class PatternMatcherPass:
def __init__(
self,
pass_name: Optional[str] = None,
) -> None:
super().__init__()
self.patterns: DefaultDict[
Tuple[str, torch.fx.node.Target], List[PatternEntry]
] = defaultdict(list)
self.pass_name = pass_name
def __getitem__(self, item: Tuple[str, torch.fx.node.Target]) -> List[PatternEntry]:
return self.patterns[item]
def apply(self, gm: Union[torch.fx.GraphModule, torch.fx.Graph]) -> int:
if not self.patterns:
return 0
if isinstance(gm, torch.fx.GraphModule):
graph = gm.graph
elif isinstance(gm, torch.fx.Graph):
graph = gm
gm = graph.owning_module
else:
raise RuntimeError(
f"The input to PatternMatcherPass must be a GraphModule or a Graph, but got {type(gm)}"
)
if should_compute_mutation_region_ids(graph): # type: ignore[arg-type]
compute_mutation_region_ids(graph) # type: ignore[arg-type]
get_mutation_region_id_partial = functools.partial(
get_mutation_region_id, graph
)
count = 0
nodes = []
has_call_module = False
for op, target in self.patterns:
if op == "call_module":
has_call_module = True
else:
nodes.append(graph.find_nodes(op=op, target=target, sort=False))
if has_call_module:
nodes.append(graph.find_nodes(op="call_module", sort=False))
pass_name = self.pass_name if self.pass_name is not None else "pattern_matcher"
assert isinstance(gm, torch.fx.GraphModule)
with GraphTransformObserver(gm, pass_name):
for node in sorted(itertools.chain.from_iterable(nodes), reverse=True):
target = extract_target(node)
if node.op == "call_module":
if (node.op, target) not in self.patterns:
continue
# conservatively not applying pattern for cpu input,
# since some of the patterns induce codegen and split nodes.
# Note: we will only skip cpu compute if disable_cpp_codegen=True
if fallback_node_due_to_unsupported_type(node, allow_cpu_inputs=False):
continue
for entry in self.patterns[(node.op, target)]:
if node._erased:
break
m = entry.pattern.match(node)
# pattern match crosses mutation barrier - discard
if (
is_match(m)
and len(OrderedSet(map(get_mutation_region_id_partial, m.nodes))) != 1 # type: ignore[possibly-undefined]
):
continue
if os.environ.get("TORCHINDUCTOR_PATTERN_MATCH_DEBUG") == node.name:
log.warning("%s%s %s %s", node, node.args, m, entry.pattern)
if is_match(m) and entry.extra_check(m):
count += 1
entry.apply(m, graph, node) # type: ignore[arg-type]
counters["inductor"]["pattern_matcher_count"] += 1
counters["inductor"]["pattern_matcher_nodes"] += len(m.nodes)
return count
def clear(self) -> None:
self.patterns.clear()
def _not_implemented(*args: Any, **kwargs: Any) -> NoReturn:
raise NotImplementedError
def fx_to_pattern(
gm: Union[torch.fx.GraphModule, torch.fx.Graph],
ignore_types: Sequence[Type[Any]] = (),
argnames: Sequence[str] = (),
scalar_workaround: Union[Dict[str, Union[float, int]], None] = None,
exclusive_arg_names: Sequence[str] = (),
) -> PatternExpr:
"""
Convert an FX graph into a PatternExpr. This is useful for simple
patterns that can only match single functions and fixed-length lists.
"""
# scalar_workaround is a hack to capture dropout_p
# see https://github.com/pytorch/pytorch/issues/97894
scalar_workaround = scalar_workaround or {}
inv_scalar_workaround = {v: k for k, v in scalar_workaround.items()}
assert len(inv_scalar_workaround) == len(scalar_workaround)
def process_arg(
x: T, ignore_types_override: Optional[Sequence[Type[Any]]] = None
) -> Union[T, KeywordArg, Ignored]:
current_ignore_types = (
ignore_types_override if ignore_types_override is not None else ignore_types
)
if isinstance(x, (float, int)) and x in inv_scalar_workaround:
return KeywordArg(inv_scalar_workaround[x])
if type(x) in current_ignore_types:
return Ignored()
if isinstance(x, list) and all(isinstance(y, Ignored) for y in x) and x:
return Ignored()
return x
argnum = itertools.count()
class Converter(torch.fx.Interpreter):
call_method = _not_implemented
call_module = _not_implemented
get_attr = _not_implemented
def placeholder(
self, target: str, args: Sequence[Any], kwargs: Mapping[str, Any] # type: ignore[override]
) -> Union[ExclusiveKeywordArg, KeywordArg]:
n = next(argnum)
if n < len(argnames):
name = argnames[n]
elif argnames:
assert target.startswith("tangent")
name = target
else:
target = re.sub(r"_\d+$", "", target) # de-mangle arg name
name = target
if name in exclusive_arg_names:
return ExclusiveKeywordArg(name)
else:
return KeywordArg(name)
def call_function(
self, target: str, args: Sequence[Any], kwargs: Mapping[str, Any] # type: ignore[override]
) -> PatternExpr:
process_arg_fn = process_arg
# Indexing is critical for matching getitem nodes, so we can't ignore int args here
if target == operator.getitem:
def process_arg_fn_impl(
x: T,
ignore_types_override: Optional[Sequence[Type[Any]]] = tuple(
t for t in ignore_types if t is not int
),
) -> Union[T, KeywordArg, Ignored]:
return process_arg(x, ignore_types_override)
process_arg_fn = process_arg_fn_impl
args, kwargs = pytree.tree_map(process_arg_fn, (args, kwargs))
if list in ignore_types:
# Handle a burned in tensor size which are now [Ignored(), Ignored(), ...]
args = [process_arg_fn(a) for a in args]
kwargs = {k: process_arg_fn(a) for k, a in kwargs.items()}
return CallFunction(target, *args, **kwargs)
def run_node(self, n: torch.fx.Node) -> Any:
rv = super().run_node(n)
if n.op == "output" and isinstance(rv, tuple):
assert len(rv) == len(n.args[0]) # type: ignore[arg-type]
for r, arg in zip(rv, n.args[0]): # type: ignore[arg-type]
r.users = len(arg.users)
else:
rv.users = len(n.users)
return rv
pattern = Converter(gm).run() # type: ignore[arg-type]
if not isinstance(pattern, PatternExpr):
return MultiOutputPattern(pytree.tree_leaves(pattern))
return pattern
@torch.no_grad()
def fwd_only(
fn: Callable[..., Any],
args: Sequence[Any],
*,
run_functional_passes: bool = True,
get_decomp_fn: Optional[Callable[..., Any]] = None,
) -> torch.fx.GraphModule:
"""Build a normalized inference graph, for use with fx_to_pattern"""
# TODO - look into using aot autograd, asserting no mutating ops here
with enable_python_dispatcher():
decompositions = (
get_decomp_fn() if get_decomp_fn is not None else select_decomp_table()
)
gm = make_fx(fn, decompositions, tracing_mode="real")(*args)
from .fx_passes.post_grad import remove_noop_ops
if run_functional_passes:
remove_noop_ops(gm.graph)
gm.graph.eliminate_dead_code()
gm.recompile()
return gm
@torch.enable_grad()
def joint_fwd_bwd(fn: Callable[..., Any], args: Sequence[Any]) -> torch.fx.GraphModule:
"""Build a normalized training graph, for use with fx_to_pattern"""
gm: Optional[torch.fx.GraphModule] = None
def record_joint_graph(
joint_graph: torch.fx.GraphModule, inputs: Sequence[Any], **kwargs: Any
) -> Tuple[torch.fx.GraphModule, torch.fx.GraphModule]:
nonlocal gm
assert not gm
gm = clone_graph(joint_graph)
return default_partition(joint_graph, inputs, **kwargs)
with torch._guards.tracing(None):
aot_function(
fn,
lambda g, i: make_boxed_func(g),
partition_fn=record_joint_graph,
decompositions=select_decomp_table(),
keep_inference_input_mutations=True,
enable_log=False,
)(*args)
assert gm
from .fx_passes.post_grad import remove_noop_ops
remove_noop_ops(gm.graph)
from .fx_passes.joint_graph import pointless_view
matcher_pass = PatternMatcherPass()
pattern = CallFunction(
torch.ops.aten.view.default, KeywordArg("arg"), KeywordArg("size")
)
GraphPatternEntry(
pattern=pattern, handler=pointless_view, extra_check=_return_true
).register(matcher_pass.patterns)
matcher_pass.apply(gm.graph) # type: ignore[arg-type]
# remove in/out specs
gm.graph._codegen = torch.fx.graph.CodeGen()
gm.graph.eliminate_dead_code()
gm.recompile()
return gm
def _args(n: torch.fx.Node) -> List[torch.fx.node.Argument]:
args: List[torch.fx.node.Argument] = []
torch.fx.map_arg((n.args, n.kwargs), args.append)
return args
def stable_topological_sort(graph: torch.fx.Graph) -> None:
# Nodes are in exactly one of these three collections:
# - Nodes in `pending` are waiting to be processed (in reverse order):
pending = list(reversed(graph.nodes))
# - Nodes in `ready` have been processed and are already in the correct
# order.
ready = OrderedSet[torch.fx.Node]()
# - `waiting` is a mapping from a dependency to nodes which depend on that
# dependency.
waiting = defaultdict(list)
# The cursor indicates the last processed node so we can add new nodes
# after it.
cursor = None
while pending:
node = pending.pop()
waiting_for = [x for x in _args(node) if x not in ready]
if waiting_for:
# We have unprocessed input nodes. Might as well wait for the last
# arg so an already sorted list will only recheck this node once.
waiting[waiting_for[-1]].append(node)
else:
ready.add(node)
if cursor and cursor.next is not node:
cursor.append(node)
cursor = node
# Mark the nodes that have been waiting for this node to finish as
# ready to check again.
pending.extend(reversed(waiting.pop(node, ())))
assert not waiting and len(ready) == len(graph.nodes)
def init_once_fakemode(fn: Callable[..., Any]) -> Callable[[], Any]:
"""Wrapper around lazy init functions in fx_passes/"""
@functools.lru_cache(None)
@functools.wraps(fn)
def lazy_init() -> Any:
counters_ref = counters["inductor"].copy()
with torch._guards.tracing(None), unset_fake_temporarily(), FakeTensorMode():
result = fn()
# clear view matches encountered during tracing
counters["inductor"] = counters_ref
return result
return lazy_init
def config_flag(name: str) -> Callable[[Match], Any]:
"""Function for extra_check to put pass behind a flag"""
def flag_check(match: Match) -> Any:
return getattr(config, name)
return flag_check
def clone_graph(input_graph: torch.fx.GraphModule) -> torch.fx.GraphModule:
class CopyGraph(Transformer):
def run_node(self, old_node: torch.fx.Node) -> torch.fx.Node:
new_node = super().run_node(old_node)
if isinstance(new_node, torch.fx.Proxy):
new_node.node.meta.update(old_node.meta)
new_node.node.name = self.new_graph._graph_namespace.create_name(
old_node.name, None
)
return new_node
return CopyGraph(input_graph).transform()
_seen_patterns = OrderedSet[str]()
def get_arg_value(
node: torch.fx.Node, arg_number: int, kwarg_name: Optional[str] = None
) -> Any:
return (
node.args[arg_number]
if len(node.args) > arg_number
else node.kwargs.get(kwarg_name) # type: ignore[arg-type]
)
def filter_nodes(nodes: Iterable[torch.fx.Node], fn: Any) -> List[torch.fx.Node]:
fns = [fn]
if isinstance(fn, torch._ops.OpOverloadPacket):
fns.extend([getattr(fn, overload) for overload in fn.overloads()])
return [node for node in nodes if node.target in fns]
def extract_target(node: torch.fx.Node) -> torch.fx.node.Target:
"""For call_function and call_method, we directly use the target function;
For call_module, the target is string, and we treat the module class
as a function.
"""
if node.op == "call_module":
return _get_attr(node.graph.owning_module, node.target).__class__ # type: ignore[arg-type]
return node.target