ai-content-maker/.venv/Lib/site-packages/torch/include/ATen/NestedTensorImpl.h

284 lines
9.8 KiB
C++

#pragma once
#include <ATen/MemoryOverlap.h>
#include <ATen/Tensor.h>
#include <c10/core/DispatchKey.h>
#include <c10/core/DispatchKeySet.h>
#include <c10/core/MemoryFormat.h>
#include <c10/core/TensorImpl.h>
#include <c10/util/ArrayRef.h>
#include <c10/util/Exception.h>
#include <c10/util/Metaprogramming.h>
#include <c10/util/irange.h>
namespace at::native {
struct NestedTensorImpl;
inline bool nested_tensor_impl_is_contiguous(const NestedTensorImpl* nt);
int64_t get_numel_from_nested_size_tensor(const at::Tensor& tensor);
struct TORCH_API NestedTensorImpl : public c10::TensorImpl {
explicit NestedTensorImpl(
Storage storage,
c10::DispatchKeySet key_set,
const caffe2::TypeMeta data_type,
at::Tensor nested_sizes,
at::Tensor nested_strides,
at::Tensor storage_offsets);
explicit NestedTensorImpl(
const at::Tensor& buffer,
at::Tensor nested_sizes,
at::Tensor nested_strides,
at::Tensor storage_offsets);
// assume contiguous, `nested_strides` and `offsets`
// can be infered from `nested_sizes`
explicit NestedTensorImpl(
const at::Tensor& buffer,
const at::Tensor& nested_sizes);
// This constructor is used creating view tensors from nested tensors
explicit NestedTensorImpl(
c10::TensorImpl::ImplType impl_type,
const at::Tensor& base_tensor,
at::Tensor nested_sizes,
at::Tensor nested_strides,
at::Tensor storage_offsets);
// TODO: don't expose private implementation details like this; in
// particular, resizing this tensor will mess up our dim() and
// callers cannot fix it.
const Tensor& get_nested_sizes() const {
return nested_sizes_;
}
// TODO: don't expose private implementation details like this
const Tensor& get_nested_strides() const {
return nested_strides_;
}
const Tensor& get_storage_offsets() const {
return storage_offsets_;
}
// Returns nullopt if the ith dimension is irregular. The ith dimension
// of a NestedTensor is regular if the unbound tensors match in
// size at the (i-1)th dimension.
c10::optional<int64_t> opt_size(int64_t d) const;
int64_t size(int64_t d) const {
c10::optional<int64_t> optional_size = this->opt_size(d);
TORCH_CHECK(
optional_size.has_value(),
"Given dimension ",
d,
" is irregular and does not have a size.");
return *optional_size;
}
/**
* Return a view of the nested tensor as a 1 dimensional contiguous tensor.
*
* The buffer tensor created by this function shares the same storage_impl as
* the original nested tensor, and therefore can be seen as a view.
*
* @return A newly constructed view tensor
*/
at::Tensor get_buffer() const {
TORCH_CHECK(
nested_tensor_impl_is_contiguous(this),
"NestedTensor must be contiguous to get buffer.");
return get_unsafe_storage_as_tensor();
}
/**
* If possible use get_buffer() instead. This function returns the storage
* as a tensor directly, which is not safe to use in general. If using this
* function, The caller must ensure to account for nested_sizes,
* nested_strides and storage_offsets.
*
* @return A newly constructed view tensor
*/
at::Tensor get_unsafe_storage_as_tensor() const {
auto buffer_key_set_ = generate_buffer_key_set();
const auto buffer_size = get_buffer_size();
auto buffer_tensor_impl = c10::make_intrusive<TensorImpl>(
c10::TensorImpl::VIEW, Storage(storage_), buffer_key_set_, data_type_);
buffer_tensor_impl->set_sizes_contiguous(
c10::makeArrayRef(static_cast<int64_t>(buffer_size)));
return Tensor(buffer_tensor_impl);
}
size_t get_buffer_size() const {
return storage_.nbytes() / data_type_.itemsize();
}
protected:
const char* tensorimpl_type_name() const override;
// TODO: numel_custom and is_contiguous_custom can be profitably overridden
// with real implementations
int64_t numel_custom() const override;
c10::SymInt sym_numel_custom() const override;
bool is_contiguous_custom(MemoryFormat) const override;
int64_t size_custom(int64_t d) const override {
return this->size(d);
}
c10::SymInt sym_size_custom(int64_t d) const override {
return c10::SymInt{this->size(d)};
}
IntArrayRef sizes_custom() const override;
c10::SymIntArrayRef sym_sizes_custom() const override;
IntArrayRef strides_custom() const override;
c10::SymIntArrayRef sym_strides_custom() const override;
// this one is real
int64_t dim_custom() const override;
c10::intrusive_ptr<TensorImpl> shallow_copy_and_detach(
const c10::VariableVersion& version_counter,
bool allow_tensor_metadata_change) const override;
c10::intrusive_ptr<TensorImpl> shallow_copy_and_detach(
c10::VariableVersion&& version_counter,
bool allow_tensor_metadata_change) const override;
void shallow_copy_from(const c10::intrusive_ptr<TensorImpl>& impl) override {
copy_tensor_metadata(
/*src_impl=*/impl.get(),
/*dest_impl=*/this,
/*version_counter=*/version_counter(),
/*allow_tensor_metadata_change=*/allow_tensor_metadata_change());
}
private:
// Must be called after any changes to our dim() to sync the state
// to TensorImpl.
void refresh_dim();
// NOLINTNEXTLINE(cppcoreguidelines-avoid-const-or-ref-data-members)
const at::Tensor nested_sizes_, nested_strides_;
// The starting positions of the underlying tensors in contiguous buffer
// i.e. the buffer memory offsets to get the underlying tensors
// The reason to keep this metadata is that, without strong enough constraint
// it cannot be derived from `nested_sizes_`
// and `nested_strides_`:
// 1. when buffer has blanks, e.g. [tensor1, blank, tensor2]
// this can happen e.g. after slicing a nested tensor
// 2. when multiple tensors share a same memory
// 3. when the nesting ordering is changed, e.g. [tensor1, tensor3, tensor2]
// Some strong enough constraints are:
// 1. every underlying tensor is contiguous in memory
// && nesting in ascending order
// NOLINTNEXTLINE(cppcoreguidelines-avoid-const-or-ref-data-members)
const at::Tensor storage_offsets_;
// NOTE: -1 here means the size is missing
// Optional to allow it to be computed lazily from nested.
// TODO: maybe we can remove this metadata since
// we can compute it from `nested_sizes_`
mutable c10::optional<std::vector<int64_t>> opt_sizes_;
template <typename VariableVersion>
c10::intrusive_ptr<TensorImpl> shallow_copy_and_detach_core(
VariableVersion&& version_counter,
bool allow_tensor_metadata_change) const;
/**
* Generates a non-nested key_set from a nested tensor.
*
* For many nested tensor kernel implementations a buffer tensor
* is generated and redispatched to a non-nested kernel this function
* generates the key set used by that buffer tensor
*
* @return Appropriate key set for non-nested tensor
*/
inline c10::DispatchKeySet generate_buffer_key_set() const {
auto buffer_key_set = this->key_set();
const bool Autograd = buffer_key_set.has_any(c10::autograd_dispatch_keyset);
// Remove nested tensor specific keys
buffer_key_set = buffer_key_set -
c10::DispatchKeySet{
c10::DispatchKey::NestedTensor,
c10::DispatchKey::AutogradNestedTensor};
// Add dense tensor specific keys
buffer_key_set =
buffer_key_set | c10::DispatchKeySet{c10::DispatchKey::Dense};
buffer_key_set = Autograd
? c10::DispatchKeySet{c10::DispatchKey::Autograd} | buffer_key_set
: buffer_key_set;
return buffer_key_set;
}
};
inline NestedTensorImpl* get_nested_tensor_impl_or_null(
const at::Tensor& tensor) {
if (tensor.is_nested()) {
return static_cast<NestedTensorImpl*>(tensor.unsafeGetTensorImpl());
}
return nullptr;
}
inline NestedTensorImpl* get_nested_tensor_impl(const at::Tensor& tensor) {
TORCH_CHECK(
tensor.is_nested(), "get_nested_tensor_impl requires a NestedTensor.");
return static_cast<NestedTensorImpl*>(tensor.unsafeGetTensorImpl());
}
inline bool nested_tensor_impl_is_contiguous(const NestedTensorImpl* nt) {
int64_t ntensors = nt->size(0);
if (ntensors == 0) {
return true;
}
const Tensor &sizemat = nt->get_nested_sizes(),
&stridemat = nt->get_nested_strides();
int64_t* offsets_ptr = nt->get_storage_offsets().data_ptr<int64_t>();
int64_t orig_dim = sizemat.size(1);
// nesting scalars
if (orig_dim == 0) {
// each scalar must be contiguous
// if there is blank memory between underlying scalars
for (int64_t i = 0; i < ntensors; i++) {
if (offsets_ptr[i] != i) {
return false;
}
}
}
// nesting tensors
else {
// if any underlying tensor is non-contiguous
const int64_t *sizemat_ptr = sizemat.data_ptr<int64_t>(),
*stridemat_ptr = stridemat.data_ptr<int64_t>();
for (int64_t i = 0; i < ntensors; i++) {
if (stridemat_ptr[orig_dim - 1] != 1) {
return false;
}
int64_t product = sizemat_ptr[orig_dim - 1];
for (int64_t j = orig_dim - 2; j >= 0; j--) {
if (stridemat_ptr[j] != product) {
return false;
}
product *= sizemat_ptr[j];
}
sizemat_ptr += orig_dim;
stridemat_ptr += orig_dim;
}
// if there is blank memory between underlying tensors
if (offsets_ptr[0] != 0) {
return false;
}
sizemat_ptr = sizemat.data_ptr<int64_t>();
stridemat_ptr = stridemat.data_ptr<int64_t>();
for (int64_t i = 1; i < ntensors; i++) {
if (offsets_ptr[i] !=
offsets_ptr[i - 1] + *sizemat_ptr * *stridemat_ptr) {
return false;
}
sizemat_ptr += orig_dim;
stridemat_ptr += orig_dim;
}
}
// everything is fine
return true;
}
inline const at::Tensor& get_nested_sizes(const at::Tensor& tensor) {
return get_nested_tensor_impl(tensor)->get_nested_sizes();
}
} // namespace at::native