| /* |
| * Copyright 2017 Facebook, Inc. |
| * |
| * 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. |
| */ |
| |
| #pragma once |
| |
| #include <folly/Portability.h> |
| |
| #ifdef _MSC_VER |
| #include <intrin.h> |
| #endif |
| |
| namespace folly { |
| inline void asm_volatile_memory() { |
| #if defined(__clang__) || defined(__GNUC__) |
| asm volatile("" : : : "memory"); |
| #elif defined(_MSC_VER) |
| ::_ReadWriteBarrier(); |
| #endif |
| } |
| |
| inline void asm_volatile_pause() { |
| #if defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64)) |
| ::_mm_pause(); |
| #elif defined(__i386__) || FOLLY_X64 |
| asm volatile("pause"); |
| #elif FOLLY_A64 || defined(__arm__) |
| asm volatile("yield"); |
| #elif FOLLY_PPC64 |
| asm volatile("or 27,27,27"); |
| #endif |
| } |
| } |