/* Copyright 2016 The OpenXLA Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================*/

#ifndef XLA_STREAM_EXECUTOR_HOST_HOST_STREAM_H_
#define XLA_STREAM_EXECUTOR_HOST_HOST_STREAM_H_

#include <cstdint>

#include "absl/functional/any_invocable.h"
#include "absl/status/status.h"
#include "xla/stream_executor/device_address.h"
#include "xla/stream_executor/event.h"
#include "xla/stream_executor/stream.h"
#include "xla/stream_executor/stream_common.h"
#include "xla/stream_executor/stream_executor.h"

namespace stream_executor {
namespace host {

// HostStream for launching work on the host CPU. In contrast to the device
// streams, HostStream is fully synchronous and launches all operations in the
// caller thread.
class HostStream : public StreamCommon {
 public:
  explicit HostStream(StreamExecutor* executor);
  ~HostStream() override;

  absl::Status BlockHostUntilDone() override { return absl::OkStatus(); }

  absl::Status WaitFor(Stream* other) override;
  absl::Status WaitFor(Event* event) override;
  absl::Status RecordEvent(Event* event) override;
  absl::Status MemZero(DeviceAddressBase* location, uint64_t size) override;
  absl::Status Memset32(DeviceAddressBase* location, uint32_t pattern,
                        uint64_t size) override;
  absl::Status Memcpy(DeviceAddressBase* gpu_dst, const void* host_src,
                      uint64_t size) override;
  absl::Status Memcpy(DeviceAddressBase* gpu_dst,
                      const DeviceAddressBase& gpu_src, uint64_t size) override;
  absl::Status Memcpy(void* host_dst, const DeviceAddressBase& gpu_src,
                      uint64_t size) override;
  absl::Status DoHostCallbackWithStatus(
      absl::AnyInvocable<absl::Status() &&> callback) override;
};

}  // namespace host
}  // namespace stream_executor

#endif  // XLA_STREAM_EXECUTOR_HOST_HOST_STREAM_H_