pytorch/tools/codegen/api/native.py
Brian Hirsh 947c7a8215 add C++ namespacing logic to ctypes (#55047)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/55047

Added namespaces to all of the `CTypes` printed in the codegen. This is pretty much required if we want to use codegen externally, since we can no longer assume that we're inside of the `at::` namespace.

Important changes are in `types.py`.

How do we add the notion of namespaces to C++ types without people having to write "at::Tensor" everywhere? Before this PR, `CType` held a raw string representing the type, i.e. `BaseCType("Tensor", binds)`. This PR introduces a set of singleton base C++ types in `types.py`, that know how to print their namespace. Instead, we'd write `BaseCType(tensorT, binds)`, where printing `tensorT` will properly print out "at::Tensor".

This also means that you can't create arbitrary `CTypes`. If we need a new C++ type in the codegen, we need to add it to the list in `types.py`.

One blip in the design: we don't want to change `RegistrationDeclarations.yaml`, since that'll break external backends that ingest it. I added separate functions to display types without the namespace that are used to create RegistrationDeclarations.yaml`. With an external codegen API though, we can eventually kill it :)

I also didn't realize until this PR that `Declarations.yaml` is still directly in use, by some python/autograd codegen. Rather than keep that yaml byte-for-byte compatible, I just updated the callsites in the autograd codegen to work with namespaces. In the NEXT pr, I try to clean up some of the autograd codegen to stop using raw strings to match against C++ types.

Test Plan: Imported from OSS

Reviewed By: bhosmer

Differential Revision: D27708349

Pulled By: bdhirsh

fbshipit-source-id: 56a4f81fc101795bcb9ee1f722121480fb2356ad
2021-04-16 11:43:06 -07:00

111 lines
4.5 KiB
Python

from tools.codegen.model import (Argument, FunctionSchema, Return,
SelfArgument, TensorOptionsArguments, Type,
assert_never)
from tools.codegen.api.types import (ArgName, BaseCType, Binding,
ConstRefCType, CType, MutRefCType, ListCType,
OptionalCType, tensorT, scalarT, layoutT,
deviceT, boolT, scalarTypeT)
from tools.codegen.api import cpp
from typing import Union, Sequence, List, Optional
# This file describes the translation of JIT schema to the native functions API.
# This looks a lot like the C++ API (which makes historical sense, because the
# idea was you wrote native functions to implement functions in the C++ API),
# but over time we have evolved the C++ API without actually changing our
# native:: kernels. The intention is to make native API and dispatcher API
# line up as closely as possible, since this results in the least overhead
# (no translation is needed from dispatcher API to native API).
def name(func: FunctionSchema) -> str:
name = str(func.name.name)
# TODO: delete this!
if func.is_out_fn():
name += '_out'
if func.name.overload_name:
name += f'_{func.name.overload_name}'
return name
def argumenttype_type(t: Type, *, mutable: bool, binds: ArgName) -> CType:
if str(t) == 'Tensor?':
tensor_type: OptionalCType = OptionalCType(BaseCType(tensorT, binds))
if mutable:
return MutRefCType(tensor_type)
else:
return ConstRefCType(tensor_type)
elif str(t) == 'Tensor?[]':
return ConstRefCType(ListCType(OptionalCType(BaseCType(tensorT, binds))))
elif str(t) == 'Scalar':
return ConstRefCType(BaseCType(scalarT, binds))
elif str(t) == 'Scalar?':
return ConstRefCType(OptionalCType(BaseCType(scalarT, binds)))
return cpp.argumenttype_type(t, mutable=mutable, binds=binds)
def returns_type(rs: Sequence[Return]) -> CType:
return cpp.returns_type(rs)
def argument_type(a: Argument, *, binds: ArgName) -> CType:
return argumenttype_type(a.type, mutable=a.is_write, binds=binds)
def argument(a: Union[Argument, SelfArgument, TensorOptionsArguments], *, is_out: bool) -> List[Binding]:
# Ideally, we NEVER default native functions. However, there are a number
# of functions that call native:: directly and rely on the defaulting
# existing. So for BC, we generate defaults for non-out variants (but not
# for out variants, where it is impossible to generate an appropriate
# default)
should_default = not is_out
if isinstance(a, Argument):
default: Optional[str] = None
if should_default and a.default is not None:
default = cpp.default_expr(a.default, a.type)
return [Binding(
ctype=argument_type(a, binds=a.name),
name=a.name,
default=default,
argument=a,
)]
elif isinstance(a, SelfArgument):
# Erase SelfArgument from the distinction
return argument(a.argument, is_out=is_out)
elif isinstance(a, TensorOptionsArguments):
default = None
if should_default:
default = '{}'
# TODO: Not sure why the arguments assigned here are for
# TensorOptionsArguments and not the constituent pieces. It seems
# to matter
return [
Binding(
ctype=OptionalCType(BaseCType(scalarTypeT, 'dtype')),
name='dtype',
default=default,
argument=a,
),
Binding(
ctype=OptionalCType(BaseCType(layoutT, 'layout')),
name='layout',
default=default,
argument=a,
),
Binding(
ctype=OptionalCType(BaseCType(deviceT, 'device')),
name='device',
default=default,
argument=a,
),
Binding(
ctype=OptionalCType(BaseCType(boolT, 'pin_memory')),
name='pin_memory',
default=default,
argument=a,
)]
else:
assert_never(a)
def arguments(func: FunctionSchema) -> List[Binding]:
args: List[Union[Argument, TensorOptionsArguments, SelfArgument]] = []
args.extend(func.arguments.non_out)
args.extend(func.arguments.out)
return [r for arg in args for r in argument(arg, is_out=func.is_out_fn())]