execution_policy.hpp

/*
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * Licensed under the Apache License Version 2.0 with LLVM Exceptions
 * (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *   https://llvm.org/LICENSE.txt
 *
 * 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.
 */
#pragma once

#include <unifex/detail/prologue.hpp>

namespace unifex {
// Execution policies are used to describe constraints on the safe execution
// of bulk operations with respect to each other.
//
// sequenced - Operations must be sequenced with respect to each other.
//             They are not safe to executed concurrently on differen threads or
//             to interleaved with each other on the same thread.
//
// unsequenced - Operations are safe to be interleaved with each other, e.g.
//               using vectorised SIMD instructions, but may not be executed
//               concurrently on different threads. This generally implies that
//               forward progress of one operation is not dependent on forward
//               progress of other operations.
//
// parallel - Operations are safe to be executed concurrently with each other on
//            different threads but operations on each thread must not be
//            interleaved.
//
// parallel_unsequenced - Operations are safe to be executed concurrently on
//                        different threads and may be interleaved with each
//                        other on the same thread.

inline constexpr struct sequenced_policy {
} seq;
inline constexpr struct unsequenced_policy {
} unseq;
inline constexpr struct parallel_policy {
} par;
inline constexpr struct parallel_unsequenced_policy {
} par_unseq;
}  // namespace unifex

#include <unifex/detail/epilogue.hpp>