Move asm portability to an Asm portability header

Summary: Portabilty.h is just a mashup of everything that was needed up-to now, however, with the Windows port significantly expanding the scope of portability in Folly, it no longer needs to be a massive mashup, so start things by splitting out the asm stubs.

Reviewed By: yfeldblum

Differential Revision: D3007018

fb-gh-sync-id: f32913f74660aaa8889a553ae5d6f7182a4f5789
fbshipit-source-id: f32913f74660aaa8889a553ae5d6f7182a4f5789

folly/Baton.h

@@ -24,6 +24,7 @@
 
 #include <folly/detail/Futex.h>
 #include <folly/detail/MemoryIdler.h>
+#include <folly/portability/Asm.h>
 
 namespace folly {
 

folly/Makefile.am

@@ -267,6 +267,7 @@ nobase_follyinclude_HEADERS = \
 	Padded.h \
 	PicoSpinLock.h \
 	Portability.h \
+	portability/Asm.h \
 	portability/Config.h \
 	portability/Constexpr.h \
 	portability/Environment.h \

folly/MicroLock.cpp

@@ -17,6 +17,8 @@
 #include <folly/MicroLock.h>
 #include <thread>
 
+#include <folly/portability/Asm.h>
+
 namespace folly {
 
 void MicroLockCore::lockSlowPath(uint32_t oldWord,

folly/Portability.h

@@ -369,43 +369,6 @@ inline size_t malloc_usable_size(void* ptr) {
 # define FOLLY_HAS_RTTI 1
 #endif
 
-#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
-}
-inline void asm_pause() {
-#if defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64))
-  ::_mm_pause();
-#elif defined(__i386__) || FOLLY_X64
-  asm ("pause");
-#elif FOLLY_A64 || defined(__arm__)
-  asm ("yield");
-#elif FOLLY_PPC64
-  asm ("or 31,31,31");
-#endif
-}
-
 #if defined(__APPLE__) || defined(_MSC_VER)
 #define MAX_STATIC_CONSTRUCTOR_PRIORITY
 #else
@@ -415,5 +378,4 @@ inline void asm_pause() {
 #define MAX_STATIC_CONSTRUCTOR_PRIORITY __attribute__ ((__init_priority__(102)))
 #endif
 
-} // namespace folly
 #endif // FOLLY_PORTABILITY_H_

folly/RWSpinLock.h

@@ -137,6 +137,7 @@ pthread_rwlock_t Read        728698     24us       101ns     7.28ms     194us
 */
 
 #include <folly/Portability.h>
+#include <folly/portability/Asm.h>
 
 #if defined(__GNUC__) && \
   (defined(__i386) || FOLLY_X64 || \

folly/SharedMutex.h

@@ -25,6 +25,7 @@
 #include <folly/Likely.h>
 #include <folly/detail/CacheLocality.h>
 #include <folly/detail/Futex.h>
+#include <folly/portability/Asm.h>
 #include <sys/resource.h>
 
 // SharedMutex is a reader-writer lock.  It is small, very fast, scalable

folly/detail/AtomicHashUtils.h

@@ -17,8 +17,8 @@
 #ifndef incl_FOLLY_ATOMIC_HASH_UTILS_H
 #define incl_FOLLY_ATOMIC_HASH_UTILS_H
 
-#include <folly/Portability.h>
 #include <thread>
+#include <folly/portability/Asm.h>
 
 // Some utilities used by AtomicHashArray and AtomicHashMap
 //

folly/detail/Sleeper.h

@@ -24,7 +24,7 @@
 #include <cinttypes>
 #include <ctime>
 
-#include <folly/Portability.h>
+#include <folly/portability/Asm.h>
 
 namespace folly {
 

folly/detail/TurnSequencer.h

@@ -22,7 +22,7 @@
 #include <unistd.h>
 
 #include <folly/detail/Futex.h>
-#include <folly/Portability.h>
+#include <folly/portability/Asm.h>
 
 namespace folly {
 

folly/experimental/fibers/Baton.cpp

@@ -19,6 +19,7 @@
 
 #include <folly/detail/MemoryIdler.h>
 #include <folly/experimental/fibers/FiberManager.h>
+#include <folly/portability/Asm.h>
 
 namespace folly { namespace fibers {
 

folly/portability/Asm.h

+/*
+ * Copyright 2016 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
+}
+
+inline void asm_pause() {
+#if defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_X64))
+  ::_mm_pause();
+#elif defined(__i386__) || FOLLY_X64
+  asm("pause");
+#elif FOLLY_A64 || defined(__arm__)
+  asm("yield");
+#elif FOLLY_PPC64
+  asm("or 31,31,31");
+#endif
+}
+}

folly/test/SmallLocksTest.cpp

@@ -31,6 +31,8 @@
 
 #include <gtest/gtest.h>
 
+#include <folly/portability/Asm.h>
+
 using folly::MSLGuard;
 using folly::MicroLock;
 using folly::MicroSpinLock;

folly/test/SpinLockTest.cpp

@@ -20,6 +20,8 @@
 #include <gtest/gtest.h>
 #include <thread>
 
+#include <folly/portability/Asm.h>
+
 using folly::SpinLockGuardImpl;
 
 namespace {