// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements.  See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership.  The ASF licenses this file

// to you 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.

#pragma once

// Compiler hint that this branch is likely or unlikely to

// be taken. Take from the "What all programmers should know

// about memory" paper.

// example: if (LIKELY(size > 0)) { ... }

// example: if (UNLIKELY(!status.ok())) { ... }

#define CACHE_LINE_SIZE 64

#ifdef LIKELY

#undef LIKELY

#endif

#ifdef UNLIKELY

#undef UNLIKELY

#endif

#define LIKELY(expr) __builtin_expect(!!(expr), 1)

#define UNLIKELY(expr) __builtin_expect(!!(expr), 0)

#define PREFETCH(addr) __builtin_prefetch(addr)

/// Force inlining. The 'inline' keyword is treated by most compilers as a hint,

/// not a command. This should be used sparingly for cases when either the function

/// needs to be inlined for a specific reason or the compiler's heuristics make a bad

/// decision, e.g. not inlining a small function on a hot path.

#ifdef ALWAYS_INLINE

#undef ALWAYS_INLINE

#endif

#define ALWAYS_INLINE __attribute__((always_inline))

#define NO_INLINE __attribute__((__noinline__))

#define MAY_ALIAS __attribute__((__may_alias__))

#define ALIGN_CACHE_LINE __attribute__((aligned(CACHE_LINE_SIZE)))

#define PURE __attribute__((pure))