arrow/util/memory.h

0001 // Licensed to the Apache Software Foundation (ASF) under one
0002 // or more contributor license agreements.  See the NOTICE file
0003 // distributed with this work for additional information
0004 // regarding copyright ownership.  The ASF licenses this file
0005 // to you under the Apache License, Version 2.0 (the
0006 // "License"); you may not use this file except in compliance
0007 // with the License.  You may obtain a copy of the License at
0008 //
0009 //   http://www.apache.org/licenses/LICENSE-2.0
0010 //
0011 // Unless required by applicable law or agreed to in writing,
0012 // software distributed under the License is distributed on an
0013 // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
0014 // KIND, either express or implied.  See the License for the
0015 // specific language governing permissions and limitations
0016 // under the License.
0017
0018 #pragma once
0019
0020 #include <cstdint>
0021 #include <memory>
0022
0023 #include "arrow/util/macros.h"
0024
0025 namespace arrow {
0026 namespace internal {
0027
0028 // A helper function for doing memcpy with multiple threads. This is required
0029 // to saturate the memory bandwidth of modern cpus.
0030 void parallel_memcopy(uint8_t* dst, const uint8_t* src, int64_t nbytes,
0031                       uintptr_t block_size, int num_threads);
0032
0033 // A helper function for checking if two wrapped objects implementing `Equals`
0034 // are equal.
0035 template <typename T>
0036 bool SharedPtrEquals(const std::shared_ptr<T>& left, const std::shared_ptr<T>& right) {
0037   if (left == right) return true;
0038   if (left == NULLPTR || right == NULLPTR) return false;
0039   return left->Equals(*right);
0040 }
0041
0042 }  // namespace internal
0043 }  // namespace arrow