// Creates a new TensorFlow function. A Function is an execution context, and as
// such it can trace operations through TF_ExecuteOperation. After completing
// tracing, a function can be obtained by TF_FinalizeFunction.
TF_ExecutionContext* TF_CreateFunction(const char* fn_name, TF_Status* status);

// Creates a context for eager execution of operations.
TF_ExecutionContext* TF_NewEagerExecutionContext(TFE_ContextOptions*,

// Registers a custom device for use with eager execution.
//
// Eager operations may be placed on this device, e.g.  `with
// tf.device("CUSTOM"):` from Python if `device_name` for this call is
// "/job:localhost/replica:0/task:0/device:CUSTOM:0".
//
// The custom device defines copy operations for moving TensorHandles on and
// off, and an execution operation for named operations. Often execution will

};

namespace internal {
struct TracingOperationDeleter {
  void operator()(TracingOperation* p) const {
    if (p != nullptr) {
      p->Release();
    }
  }
};
}  // namespace internal

using TracingOperationPtr =
    std::unique_ptr<TracingOperation, internal::TracingOperationDeleter>;

// This holds the context for the execution: dispatching operations either to an
// MLIR implementation or to a graph implementation.

      : AbstractContext(kind) {}
  ~ImmediateExecutionContext() override {}
};

namespace internal {
struct ImmediateExecutionContextDeleter {
  void operator()(ImmediateExecutionContext* p) const {
    if (p != nullptr) {
      p->Release();
    }
  }
};
}  // namespace internal

using ImmediateContextPtr =
    std::unique_ptr<ImmediateExecutionContext,

        strings::StrCat("Plugin ABI (", pluginABI, ") for ", where,
                        " operations doesn't match expected core ABI (",
                        coreABI, "). Plugin cannot be loaded."));
  return OkStatus();
}

// Checks if the plugin and core ABI numbers match, for all operations.
//
// If the numbers don't match, plugin cannot be loaded.
//
// Uses the simpler `CheckABI(int, int, StringPiece)`.

      read_only_memory_region_ops_;
  std::function<void*(size_t)> plugin_memory_allocate_;
  std::function<void(void*)> plugin_memory_free_;
  ModularFileSystem(const ModularFileSystem&) = delete;
  void operator=(const ModularFileSystem&) = delete;
};

class ModularRandomAccessFile final : public RandomAccessFile {
 public:
  ModularRandomAccessFile(const std::string& filename,

/// that plugins provide (some are mandatory, some are optional, with or without
/// a default implementation).
///
/// Each plugin implements the operations that are supported and TensorFlow will
/// properly handle the cases when an operation is not supported (i.e., return
/// the corresponding `Status` value).
///

  AbstractTensorHandleKind getKind() const { return kind_; }

 private:
  const AbstractTensorHandleKind kind_;
};

namespace internal {
struct AbstractTensorHandleDeleter {
  void operator()(AbstractTensorHandle* p) const {
    if (p != nullptr) {
      p->Unref();
    }
  }
};
}  // namespace internal

// TODO(b/185908092): Make AbstractTensorHandlePtr an IntrusivePtr.

// maintains the map from `op_id` to a `OpTapeEntry` which stores the `op_type`,
// inputs and outputs and the gradient function These data structures combined
// allow us to trace the data dependencies between operations and hence compute
// gradients.
//
// `ZerosLike` is not expected to be called and returns a nullptr. The creation
// of default zeros grads is handled by the `DefaultGradientFunction` registered
// for each op.

variables as part of those interactions (ex: using a string variable to build a
filesystem path), a maliciously created checkpoint might be able to change the
targets of those operations, which could result in arbitrary
read/write/executions.

### Running a TensorFlow server

TensorFlow is a platform for distributed computing, and as such there is a