pytorch/torch/_inductor/graph.py
Aaron Gokaslan 3d82d8d0ed [BE] Enable more flake8-comprehensions checks (#94601)
I applied some flake8 fixes and enabled checking for them in the linter. I also enabled some checks for my previous comprehensions PR.

This is a follow up to #94323 where I enable the flake8 checkers for the fixes I made and fix a few more of them.

Pull Request resolved: https://github.com/pytorch/pytorch/pull/94601
Approved by: https://github.com/ezyang
2023-02-10 23:40:29 +00:00

605 lines
23 KiB
Python

import logging
import operator
import os
import re
import sys
import time
from typing import Dict, List, Optional, Set
import sympy
import torch
import torch.fx
from torch._decomp import get_decompositions
from torch._dynamo.utils import dynamo_timed
from torch.fx.experimental.symbolic_shapes import ShapeEnv
from torch.utils._mode_utils import no_dispatch
from .._dynamo import config as dynamo_config
from . import config, ir
from .codegen.wrapper import CppWrapperCodeGen, WrapperCodeGen
from .exc import (
LoweringException,
MissingOperatorWithDecomp,
MissingOperatorWithoutDecomp,
)
from .ir import Constant, FixedLayout, InputBuffer, Pointwise, Reduction, TensorBox
from .lowering import (
FALLBACK_ALLOW_LIST,
layout_constraints,
lowerings,
make_fallback,
needs_realized_inputs,
)
from .sizevars import CppSizeVarAllocator, SizeVarAllocator
from .utils import (
convert_shape_to_inductor,
gather_origins,
get_dtype_size,
sympy_product,
)
from .virtualized import V
log = logging.getLogger(__name__)
def supported_dtype_of_cpp_wrapper(dtype):
supported_dtype = {
torch.float32,
torch.float64,
torch.int64,
torch.int32,
torch.int16,
torch.int8,
torch.uint8,
torch.bool,
# torch.float16, # TODO: implement this
# torch.bfloat16, # TODO: implement this
}
return dtype in supported_dtype
class GraphLowering(torch.fx.Interpreter):
def symbolic_sizes_strides(self, ex: torch.Tensor):
"""
Support dynamic shapes and dynamic strides by assigning variables
to each dimension. We duck-shape tensors, so if two tensors
have the same size they get assigned the same symbolic variable.
"""
if self.reuse_shape_env:
return convert_shape_to_inductor(ex.size()), convert_shape_to_inductor(
ex.stride()
)
else:
from torch._dynamo.source import ConstantSource
# TODO: this should not be needed once #93059 lands
# https://github.com/pytorch/pytorch/pull/94031#discussion_r1096044816
# TODO: make a dedicated UnknownSource for this?
source = ConstantSource(
f"__unknown_tensor_{len(self._shape_env.var_to_val)}"
)
(
size,
stride,
_,
) = self._shape_env.create_symbolic_sizes_strides_storage_offset(ex, source)
size = [i.node.expr if isinstance(i, torch.SymInt) else i for i in size]
stride = [i.node.expr if isinstance(i, torch.SymInt) else i for i in stride]
return size, stride
def static_sizes_strides(self, ex: torch.Tensor):
"""
Primarily used to weights
"""
size = [sympy.Integer(i) for i in ex.size()]
stride = [sympy.Integer(i) for i in ex.stride()]
return size, stride
def __init__(
self,
gm: torch.fx.GraphModule,
shape_env=None,
num_static_inputs=None,
graph_id=None,
):
super().__init__(gm)
if shape_env is None:
shape_env = ShapeEnv()
self.reuse_shape_env = False
else:
self._shape_env = shape_env
self.reuse_shape_env = True
self._shape_env = shape_env
self.sizevars = SizeVarAllocator(shape_env)
self.graph_inputs: Dict[str, TensorBox] = {}
self.graph_inputs_original: Dict[str, InputBuffer] = {}
self.graph_outputs: Optional[List[ir.IRNode]] = None
self.device_types: Set[str] = set()
self.buffers: List[ir.ComputedBuffer] = []
self.constants: Dict[str, torch.Tensor] = {}
self.removed_buffers: Set[str] = set()
self.inplaced_to_remove: Set[str] = set()
self.wrapper_code = None
self.num_static_inputs = num_static_inputs
self.mutated_inputs: Set[str] = set()
self.unaligned_buffers: Set[str] = set()
self.randomness_offset = sympy.Integer(0)
self.randomness_seeds: List[str] = []
self.name_to_buffer: Dict[str, ir.ComputedBuffer] = {}
self.creation_time = time.time()
self.name = "GraphLowering"
self._can_use_cpp_wrapper = config.cpp_wrapper
self.graph_id = graph_id
self.scheduler = None
self._warned_fallback = {"aten.convolution_backward"}
def warn_fallback(self, name):
if name not in self._warned_fallback:
self._warned_fallback.add(name)
log.info(f"Using FallbackKernel: {name}")
@property
def fake_mode(self):
return V.fake_mode
def get_dtype(self, buffer_name: str):
if buffer_name in self.constants:
return self.constants[buffer_name].dtype
if buffer_name in self.name_to_buffer:
return self.name_to_buffer[buffer_name].get_dtype()
if buffer_name in self.graph_inputs:
return self.graph_inputs[buffer_name].get_dtype()
m = re.match(r"as_strided\(([a-zA-Z0-9_]+),", buffer_name)
if m:
return self.get_dtype(m.group(1))
raise KeyError(f"could not find {buffer_name}")
def random_seed_buffer(self, device: torch.device):
"""
Return a device-unique 1-element tensor storing our RNG seed.
This will get initialized at the start of each graph in
`wrapper.py`.
Note this is only used by cuda backends. The CPU backend handles
RNG seeds as a sizevar.
"""
name = f"seed_{device.type}_{device.index}"
if name not in self.constants:
self.constants[name] = torch.zeros((), device=device, dtype=torch.int64)
self.randomness_seeds.append(name)
return ir.RandSeedBuffer(
name=name,
layout=ir.FixedLayout(
device=device,
dtype=torch.int64,
size=[],
stride=[],
),
)
def increment_randomness_offset(self, numel):
"""
A global counter of how many random numbers we have handed out so far.
"""
offset = self.randomness_offset
self.randomness_offset = offset + numel
return offset
@dynamo_timed
def run(self, *args):
return super().run(*args)
def disable_cpp_wrapper(self, cond):
self._can_use_cpp_wrapper = False
log.debug("Set _can_use_cpp_wrapper to False due to %s", cond)
def check_buffer_for_cpp_wrapper(self, buffer: ir.ComputedBuffer):
if isinstance(buffer, ir.ExternKernel):
if not getattr(buffer, "cpp_kernel", False):
self.disable_cpp_wrapper("ExternKernel")
def register_buffer(self, buffer: ir.ComputedBuffer):
if config.cpp_wrapper:
self.check_buffer_for_cpp_wrapper(buffer)
name = f"buf{len(self.buffers)}"
self.buffers.append(buffer)
self.name_to_buffer[name] = buffer
return name
def realize_users_of(self, name: str):
"""
When a buffer is mutated we need to make sure all the reads to
the old version are realized before the mutation happens.
"""
assert isinstance(name, str)
def visit(value):
if isinstance(value, (list, tuple)):
return [visit(x) for x in value]
if isinstance(value, ir.IRNode):
if value.is_user_of(name):
value.realize()
return value
for key, value in self.env.items():
try:
visit(value)
except Exception:
log.warning("error in realize_users_of", exc_info=True)
def add_tensor_constant(self, data):
def allocate():
for name, value in self.constants.items():
if (
data.size() == value.size()
and data.stride() == value.stride()
and data.dtype == value.dtype
and data.device == value.device
and torch.eq(data, value).all()
):
return name
name = f"constant{len(self.constants)}"
self.constants[name] = data
return name
return TensorBox.create(
ir.ConstantBuffer(
allocate(),
FixedLayout(data.device, data.dtype, *self.static_sizes_strides(data)),
)
)
def constant_name(self, name: str, device_override: torch.device):
"""
We AOT copy constants to the devices they are needed on.
If device_override doesn't match the constant's device, then
copy it and return a different name.
"""
if self.constants[name].device == device_override or device_override is None:
return name
alt_name = f"{name}_{device_override.type}{device_override.index or 0}"
if alt_name not in self.constants:
self.constants[alt_name] = self.constants[name].to(device_override)
return alt_name
def placeholder(self, target: str, args, kwargs):
example: torch.Tensor = super().placeholder(target, args, kwargs)
# todo(chilli): We can remove the last check once we turn buffers into
# static shape tensors. That's a hack to workaround Inductor believing
# the buffer should be static but us passing in a fake tensor with
# symbolic shapes.
if (
config.static_weight_shapes
and (
len(self.graph_inputs) < self.num_static_inputs
or not dynamo_config.dynamic_shapes
)
and not example._has_symbolic_sizes_strides
):
# the first N inputs are weights
sizes, strides = self.static_sizes_strides(example)
else:
sizes, strides = self.symbolic_sizes_strides(example)
# TODO(jansel): handle input aliasing
tensor = TensorBox.create(
InputBuffer(
target,
FixedLayout(example.device, example.dtype, sizes, strides),
)
)
self.graph_inputs[target] = tensor
self.graph_inputs_original[target] = tensor.data.data
self.device_types.add(example.device.type)
return tensor
def call_function(self, target, args, kwargs):
with ir.IRNode.current_origins(gather_origins(args, kwargs)):
if target is operator.getitem and isinstance(args[0], (list, tuple)):
return super().call_function(target, args, kwargs)
if hasattr(target, "_inductor_lowering_function"):
# passthrough lowerings from .pattern_matcher
return target(*args, **kwargs)
if target not in lowerings:
base_name = target.name().split(".")[0]
if base_name in FALLBACK_ALLOW_LIST:
make_fallback(target)
elif config.implicit_fallbacks:
error = (
MissingOperatorWithDecomp
if get_decompositions([target])
else MissingOperatorWithoutDecomp
)
log.info(
"Creating implicit fallback for:\n%s",
error.operator_str(target, args, kwargs),
)
make_fallback(target)
elif get_decompositions([target]):
# There isn't a good way to dynamically patch this in
# since AOT Autograd already ran. The error message tells
# the user how to fix it.
raise MissingOperatorWithDecomp(target, args, kwargs)
else:
raise MissingOperatorWithoutDecomp(target, args, kwargs)
try:
out = lowerings[target](*args, **kwargs)
return out
except Exception as e:
log.exception("Error from lowering")
raise LoweringException(e, target, args, kwargs) from e
def get_attr(self, target, args, kwargs):
# this is a constant
value = getattr(self.module, target)
with no_dispatch():
if value.shape == ():
return Constant(value.item(), value.dtype, value.device)
if len(value.shape) == 1 and value.shape[0] <= 8:
# tensor lowering has constant inlining logic
from .lowering import tensor
return tensor(value.tolist(), dtype=value.dtype, device=value.device)
return self.add_tensor_constant(value)
def call_module(self, target, args, kwargs):
raise AssertionError()
def call_method(self, target, args, kwargs):
raise AssertionError()
def output(self, target, args, kwargs):
result = super().output(target, args, kwargs)
assert isinstance(result, (tuple, list)), type(result)
assert all(
isinstance(
x,
(
TensorBox,
ir.Constant,
type(None),
ir.ConstantBuffer,
sympy.Expr,
int,
),
)
for x in result
), result
self.graph_outputs = [ir.ExternKernel.realize_input(x) for x in result]
for name, value in self.graph_inputs.items():
value.realize()
assert isinstance(value, TensorBox)
value = value.data
assert isinstance(value, ir.StorageBox)
value_storage_box = value
value = value.data
if not isinstance(value, InputBuffer) or value.get_name() != name:
# one of our inputs was mutated, need to turn that into a copy
ir.MutationLayout.realize_into(value, self.graph_inputs_original[name])
# replace output with mutated input
try:
ind = self.graph_outputs.index(value_storage_box)
self.graph_outputs[ind] = self.graph_inputs_original[name]
except ValueError:
pass
self.finalize()
def finalize(self):
for buf in self.buffers:
buf.decide_layout()
def run_node(self, n: torch.fx.Node):
with ir.IRNode.current_origins({n}):
if n.op == "call_function" and n.target in layout_constraints:
args, kwargs = self.fetch_args_kwargs_from_env(n)
args, kwargs = layout_constraints[n.target](n, *args, **kwargs)
result = self.call_function(n.target, args, kwargs)
else:
result = super().run_node(n)
# require the same stride order for dense outputs,
# 1. user-land view() will not throw because inductor
# output different strides than eager
# long term the solution is to make view() always succeed
# with infallible strides.
# 2: as_strided ops, we need make sure its input has same size/stride with
# eager model to align with eager behavior.
as_strided_ops = [
torch.ops.aten.as_strided.default,
torch.ops.aten.as_strided_.default,
torch.ops.aten.as_strided_scatter.default,
]
if any(
user.op == "output" or user.target in as_strided_ops for user in n.users
) and isinstance(n.meta["val"], torch.Tensor):
strides = n.meta["val"].stride()
dense = torch._prims_common.is_non_overlapping_and_dense(n.meta["val"])
# requiring a stride order for a non-dense output wouldn't
# recreate the same strides, and would fail with view, defer for now.
if dense and len(strides):
result = ir.ExternKernel.require_stride_order(
result, ir.get_stride_order(strides)
)
# Realize if (1) any user need inputs realized, or (2) there is
# already too many reads and rematerializing can be bad.
num_users = len(set(n.users))
if num_users > 1 and isinstance(result, TensorBox):
for user in n.users:
if user.target in needs_realized_inputs:
result.realize_hint()
# This inclusion is somewhat controversial (from
# discussion between Horace, Natalia, and Elias).
# Currently, it's not very clear why this is helpful.
# The general idea here is that even though a node may
# have FlexibleLayout, we still often *treat* it as if
# it was contiguous. This appears to sometime result in
# suboptimal behavior.
#
# When we do a better job selecting layout, we should
# revisit this.
if user.target in (
torch.ops.aten.convolution.default,
torch.ops.aten.convolution_backward.default,
torch.ops.aten.mm.default,
):
result = ir.ExternKernel.require_stride_order(
result, ir.get_stride_order(n.meta["val"].stride())
)
if user.op == "output":
if isinstance(result.data.data, (Pointwise, Reduction)):
result.realize()
# TODO(jansel): introduce a store vs inline choice
result.mark_reuse(len(n.users))
# Realize if the IRNode already has accumulated lots of reads
if isinstance(result, TensorBox) and result.has_exceeded_max_reads():
# Prevent excessive accumulation in a computed buffer, when
# there are multiple branches meach with small number of memory
# reads, but they converge to a user.
result.realize_hint()
return result
def check_platform(self):
if sys.platform != "linux":
self.disable_cpp_wrapper("platform not linux")
def check_profiler_mark_wrapper_call(self):
if config.profiler_mark_wrapper_call:
self.disable_cpp_wrapper("profiler not supported")
def check_device_for_cpp_buffer(self):
if len(self.device_types) == 1:
device = self.device_types.pop()
if device == "cpu":
return
self.disable_cpp_wrapper("device not CPU")
def check_input_for_cpp_buffer(self):
for _, value in self.graph_inputs.items():
if not supported_dtype_of_cpp_wrapper(value.get_dtype()):
self.disable_cpp_wrapper("unsupported inputs dtype")
def check_constant_for_cpp_buffer(self):
if self.constants:
self.disable_cpp_wrapper("Constants")
def check_cpp_wrapper(self):
self.check_platform()
self.check_profiler_mark_wrapper_call()
self.check_device_for_cpp_buffer()
self.check_input_for_cpp_buffer()
self.check_constant_for_cpp_buffer()
def init_wrapper_code(self):
if config.cpp_wrapper:
self.check_cpp_wrapper()
if self._can_use_cpp_wrapper:
self.sizevars = CppSizeVarAllocator(self._shape_env)
self.wrapper_code = CppWrapperCodeGen()
return
self.wrapper_code = WrapperCodeGen()
return
def codegen(self):
from .scheduler import Scheduler
self.init_wrapper_code()
self.scheduler = Scheduler(self.buffers)
assert self.scheduler is not None # mypy can't figure this out
self.scheduler.codegen()
assert self.wrapper_code is not None
return self.wrapper_code.generate()
def count_bytes(self):
from .scheduler import FusedSchedulerNode, NopKernelSchedulerNode, Scheduler
scheduler = Scheduler(self.buffers)
def get_read_write_buffers_sizes(node):
if isinstance(node, NopKernelSchedulerNode):
return 0
reads = set(dep.name for dep in node.read_writes.reads)
writes = set(dep.name for dep in node.read_writes.writes)
def is_materialized(buf):
buf_uses = {user.node for user in scheduler.name_to_node[buf].users}
return len(buf_uses - set(node.snodes)) > 0
if isinstance(node, FusedSchedulerNode):
removed_buffers = set(dep for dep in writes if not is_materialized(dep))
writes = writes - removed_buffers
reads = reads - removed_buffers
node_bytes = 0
for buf in reads | writes:
if buf in self.name_to_buffer:
buf = self.name_to_buffer[buf]
elif buf in self.graph_inputs:
buf = self.graph_inputs[buf]
else:
continue
node_bytes += V.graph.sizevars.size_hint(
sympy_product(buf.get_size())
) * get_dtype_size(buf.get_dtype())
return node_bytes
total_bytes = 0
node_counts = []
for node in scheduler.nodes:
num_bytes = get_read_write_buffers_sizes(node)
node_counts.append((node, num_bytes // 4))
total_bytes += num_bytes
return total_bytes, node_counts
@dynamo_timed
def compile_to_module(self):
from .codecache import PyCodeCache
code = self.codegen()
if config.debug:
print(code)
mod = PyCodeCache.load(code)
for name, value in self.constants.items():
setattr(mod, name, value)
if dynamo_config.output_code:
log.info("Output code: %s", mod.__file__)
V.debug.output_code(mod.__file__)
V.debug.rename(os.path.splitext(mod.__file__)[0] + ".debug")
return mod
def compile_to_fn(self):
return self.compile_to_module().call
def get_output_names(self):
assert self.graph_outputs is not None
return [
node.get_name()
for node in self.graph_outputs
if not isinstance(node, ir.NoneAsConstantBuffer)
and not isinstance(node, ir.ShapeAsConstantBuffer)
]
def is_unspec_arg(self, name: str):
# dynamo wraps unspec variable as 0d CPU tensor,
# need to convert to scalar during codegen (triton only)
return (
name in self.graph_inputs.keys()
and self.graph_inputs[name].get_numel() == 1
and self.graph_inputs[name].get_device().type == "cpu"
)