Commit Graph

5 Commits

Author SHA1 Message Date
Brian Hirsh
960758b0b7 fix overload ambiguity with functional ops; fix _foreach op grouping (#80556)
This should fix the last issue that @anijain2305 hit when running ResNet with TorchDynamo <> functionalization.

Today if you try to call an `OpOverloadPacket` from python with some arguments, we will use the types of those arguments to perform overload resolution. With some functional variants of ops, this can be ambiguous.

Today this affects just one op: `_fused_moving_avg_obs_fq_helper`, although it would potentially affect e.g. `native_batch_norm` in the future.

Example:
```
# There are technically two overloads:
# torch.ops.aten._fused_moving_avg_obs_fq_helper.default (returns 2 argument, mutates 4 of its inputs inplace)
# torch.ops.aten._fused_moving_avg_obs_fq_helper.functional (returns 6 argument, mutates none of its inputs)

# We pick the wrong one - no way to know that we should pick the functional one, just from the call site.
outs = torch.ops.aten._fused_moving_avg_obs_fq_helper(a, a, a, a, a, a, a, 1.0, 0, 1, 0)
# raises an error - tries to call the overload with only 2 returns
return _fused_moving_avg_obs_fq_helper_functional[5]
```

Specifically, functionalization will bake `_fused_moving_avg_obs_fq_helper.functional` into the graph, but when AOTAutograd tries to compile with TorchScript, it needs to remove the overload name (TS doesn't know how to parse overload names directly, so we need to remove the overload name and let it infer the right overload at runtime later- so it picks the wrong one).

The situation is pretty similar to inplace; `ops.aten.add` and `ops.aten.add_` represent two different `OverloadPacket` objects; they can't be overloads of the same op, because their schemas would be ambiguous - the alias annotations are different, but that isn't enough to disambiguate).

In this PR, I try to fix the situation in a pretty similar way to how we handle `inplace` in the data model: `inplace` ops get their own base operator name, but they are represented as a flag inside of `BaseOperatorName` in the data model.

Two other important changes that I made as part of this PR:

(1) Originally, there were ~100 different `*_functional` operators: e.g. we had operators named `resize.functional` and `zero.functional`. The `_functional` bit isn't actually necessary in most cases: it's only necessary for operators that **also** have a `SchemaKind.mutable` variant, where `_fused_moving_avg_obs_fq_helper` is the only op that fits that description today. So I removed the unnecessary notion of "functional" from those other ops. I also added a bunch of assertions to force this restriction.

I think that makes more sense in the long run, because it eliminates an unnecessary difference in the model. E.g. we don't have `add_.Tensor` and `add.Tensor_functional`. We just have `add_.Tensor` and `add.Tensor`.

(2) I noticed that we actually still weren't pairing up a bunch of `_foreach` operators correctly, because their input arguments were different (`self` vs. `tensors`). Since they're private API's, I went ahead and changed the argument names directly so they get matched up. Before this PR, we were generating a separate `_foreach_add` and `_foreach_add.functional` variant in a bunch of cases, that really did the same thing (but happened to have a different name for the first argument).

Pull Request resolved: https://github.com/pytorch/pytorch/pull/80556
Approved by: https://github.com/ezyang, https://github.com/albanD
2022-07-06 12:45:11 +00:00
Brian Hirsh
adf8060600 add a new alias key for functional to view op decompositions
Pull Request resolved: https://github.com/pytorch/pytorch/pull/79615

Approved by: https://github.com/zou3519
2022-06-15 23:18:09 +00:00
Mengwei Liu
24050a5801 [RFC][Codegen] Add custom namespace support (#78015)
Summary:
Adding a feature to allow user to specify namespaces for operator and kernels.

# Feature
There's a feature request to allow DSL to:
1. take in an operator namespace other than `aten`.
2. take in a kernel that is in a different namespace than `at::native`.

For both features, we only allow user to have a single layer of namespace for the sake of simplicity. If user specify `custom::function` as kernel, the codegen will depend on `custom::native::function` where `native` is hardcoded.

# Proposal

For feature 1, add a `namespace` attribute to data class `NativeFunction`. The namespace will be extract out by matching pattern "::" on the `func` variable. For `NativeFunctionsGroup` there's an assumption that all variants (function, inplace, out) will have the same namespace. By default (if not specified) the namespace will be "aten".

For feature 2, add a `namespace` attribute to `BackendMetadata` class, similarly match pattern "::" on the kernel field. Remove the `cpp_namespace` field from `register_dispatch_key` data class. By default (if not specified) the namespace for a kernel would be "at::native".

Test Plan:
Example yaml entries:
```
- func: custom::gelu.out(Tensor self, *, str approximate='none', Tensor(a!) out) -> Tensor(a!)
  structured: True
  structured_inherits: TensorIteratorBase
  device_check: NoCheck   # TensorIterator
  python_module: nn
  dispatch:
    CPU: custom::gelu_out_cpu
    CUDA: custom::gelu_out_cuda
    MPS: custom::gelu_out_mps

- func: custom::gelu_(Tensor(a!) self, *, str approximate='none') -> Tensor(a!)
  structured_delegate: gelu.out
  device_check: NoCheck   # TensorIterator
  python_module: nn
  dispatch:
    NestedTensorCPU, NestedTensorCUDA: custom::NestedTensor_gelu_

- func: custom::gelu(Tensor self, *, str approximate='none') -> Tensor
  structured_delegate: gelu.out
  device_check: NoCheck   # TensorIterator
  python_module: nn
  dispatch:
    MkldnnCPU: custom::mkldnn_gelu
    QuantizedCPU: custom::gelu_quantized_cpu
    NestedTensorCPU, NestedTensorCUDA: custom::NestedTensor_gelu
```

see generated code:

`RegisterCPU.cpp`:
```
TORCH_LIBRARY_IMPL(aten, CPU, m) {
  ...
}
TORCH_LIBRARY_IMPL(custom, CPU, m) {
    m.impl("gelu", TORCH_FN(wrapper_gelu));
    m.impl("gelu.out", TORCH_FN(wrapper_gelu_out_out));
    m.impl("gelu_", TORCH_FN(wrapper_gelu_));
};
```
```
struct structured_gelu_out_cpu_inplace final : public custom::native::structured_gelu_out_cpu {
    structured_gelu_out_cpu_inplace(Tensor& self) : outputs_{std::ref(self)} {}

    void set_output_strided(
        int64_t output_idx, IntArrayRef sizes, IntArrayRef strides,
        TensorOptions options, DimnameList names
    ) override {

        const auto& out = outputs_[output_idx].get();
        check_inplace(out, sizes, options);

        auto maybe_proxy = maybe_create_proxy(out, sizes, strides, options);
        if (C10_UNLIKELY(maybe_proxy.has_value())) {
            proxy_outputs_[output_idx] = c10::ExclusivelyOwned<Tensor>(std::move(maybe_proxy).value());
        }

        if (!names.empty()) {
          namedinference::propagate_names(outputs_[output_idx], names);
        }
        // super must happen after, so that downstream can use maybe_get_output
        // to retrieve the output
        custom::native::structured_gelu_out_cpu::set_output_raw_strided(output_idx, sizes, strides, options, names);
    }

    void set_output_raw_strided(
        int64_t output_idx, IntArrayRef sizes, IntArrayRef strides,
        TensorOptions options, DimnameList names
    ) override {

        const auto& out = outputs_[output_idx].get();
        check_inplace(out, sizes, options);

        if (!names.empty()) {
          namedinference::propagate_names(outputs_[output_idx], names);
        }
        // super must happen after, so that downstream can use maybe_get_output
        // to retrieve the output
        custom::native::structured_gelu_out_cpu::set_output_raw_strided(output_idx, sizes, strides, options, names);
    }

    const Tensor& maybe_get_output(int64_t output_idx) override {
      return proxy_outputs_[output_idx].has_value() ? **proxy_outputs_[output_idx] : outputs_[output_idx].get();

    }
    std::array<std::reference_wrapper<Tensor>, 1> outputs_;
    std::array<c10::optional<c10::ExclusivelyOwned<Tensor>>, 1> proxy_outputs_;
};
```

`RegisterSchema.cpp`
```
TORCH_LIBRARY(aten, m) {
  ...
}
TORCH_LIBRARY(custom, m) {
    m.def("gelu.out(Tensor self, *, str approximate='none', Tensor(a!) out) -> Tensor(a!)");

    m.def("gelu_(Tensor(a!) self, *, str approximate='none') -> Tensor(a!)");

    m.def("gelu(Tensor self, *, str approximate='none') -> Tensor");
};
```

Differential Revision: D36558459

Pull Request resolved: https://github.com/pytorch/pytorch/pull/78015
Approved by: https://github.com/bdhirsh
2022-06-10 21:04:36 +00:00
Brian Hirsh
67b27a7bae generate kernels for codegend out= operators
Pull Request resolved: https://github.com/pytorch/pytorch/pull/78626

Approved by: https://github.com/ezyang, https://github.com/JacobSzwejbka, https://github.com/larryliu0820
2022-06-06 15:36:28 +00:00
Brian Hirsh
0161e9eb00 [test] attempt to functionalize ops with mutable positional-only args
Pull Request resolved: https://github.com/pytorch/pytorch/pull/76320

Approved by: https://github.com/ezyang
2022-05-19 18:50:34 +00:00