/* Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.

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. */

#include "paddle/phi/common/place.h"

#include <sstream>
#include <string>
#include <unordered_map>

#include "paddle/phi/api/ext/exception.h"

namespace phi {

const char *AllocationTypeStr(AllocationType type) {
  switch (type) {
    case AllocationType::UNDEFINED:
      return "undefined";
    case AllocationType::CPU:
      return "cpu";
    case AllocationType::GPU:
      return "gpu";
    case AllocationType::GPUPINNED:
      return "gpu_pinned";
    case AllocationType::XPU:
      return "xpu";
    case AllocationType::NPU:
      return "npu";
    case AllocationType::NPUPINNED:
      return "npu_pinned";
    case AllocationType::IPU:
      return "ipu";
    case AllocationType::MLU:
      return "mlu";
    default:
      PD_THROW("Invalid phi device type.");
      return {};
  }
}

std::string Place::DebugString() const {
  std::ostringstream os;
  os << "Place(";
  if (alloc_type_ == AllocationType::CUSTOM) {
    os << GetGlobalDeviceType(device_type_id_);
  } else {
    os << AllocationTypeStr(alloc_type_);
  }
  if (alloc_type_ == AllocationType::GPUPINNED ||
      alloc_type_ == AllocationType::NPUPINNED ||
      alloc_type_ == AllocationType::CPU) {
    os << ")";
  } else {
    os << ":" << std::to_string(device) << ")";
  }
  return os.str();
}

std::ostream &operator<<(std::ostream &os, const Place &p) {
  os << p.DebugString();
  return os;
}

static std::unordered_map<std::string, size_t> global_registered_device_type_id;
static std::unordered_map<size_t, std::string> global_registered_device_type;

size_t GetOrRegisterGlobalDeviceTypeId(const std::string &device_type) {
  if (device_type.empty()) return 0;
  if (global_registered_device_type_id.find(device_type) ==
      global_registered_device_type_id.end()) {
    size_t device_type_id = global_registered_device_type_id.size() + 1;
    global_registered_device_type_id[device_type] = device_type_id;
    global_registered_device_type[device_type_id] = device_type;
  }
  return global_registered_device_type_id[device_type];
}

std::string GetGlobalDeviceType(size_t device_type_id) {
  if (global_registered_device_type.find(device_type_id) ==
      global_registered_device_type.end())
    return "";
  return global_registered_device_type[device_type_id];
}

constexpr static int kAllocationTypeBitLength = 8;
constexpr static int kDeviceTypeIDBitLength = 8;
constexpr static int kDeviceIDBitLength = 8;

uint32_t Place::Hash::operator()(const Place &place) const {
  uint32_t hash_value = 0;
  // |----31-24------|-----23-16------|-----15-08----|---7-0----|
  // | For extension | AllocationType | DeviceTypeID | DeviceID |
  hash_value |= (static_cast<uint8_t>(place.alloc_type_)
                 << (kDeviceIDBitLength + kDeviceTypeIDBitLength));
  hash_value |=
      (static_cast<uint8_t>(place.device_type_id_) << kDeviceIDBitLength);
  hash_value |= static_cast<uint8_t>(place.device);
  return hash_value;
}

}  // namespace phi