Rename "NoBarrier" memory operations to "Relaxed".

src/base/atomicops.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // The routines exported by this module are subtle.  If you use them, even if
 // you get the code right, it will depend on careful reasoning about atomicity
 // and memory ordering; it will be less readable, and harder to maintain.  If
 // you plan to use these routines, you should have a good reason, such as solid
 // evidence that performance would otherwise suffer, or there being no
 // alternative.  You should assume only properties explicitly guaranteed by the
 // specifications in this file.  You are almost certainly _not_ writing code
 // just for the x86; if you assume x86 semantics, x86 hardware bugs and
 // implementations on other archtectures will cause your code to break.  If you
 // do not know what you are doing, avoid these routines, and use a Mutex.
 //
 // It is incorrect to make direct assignments to/from an atomic variable.
-// You should use one of the Load or Store routines.  The NoBarrier
-// versions are provided when no barriers are needed:
-//   NoBarrier_Store()
-//   NoBarrier_Load()
+// You should use one of the Load or Store routines.  The Relaxed  versions
+// are provided when no fences are needed:
+//   Relaxed_Store()
+//   Relaxed_Load()
 // Although there are currently no compiler enforcement, you are encouraged
 // to use these.
 //
 
 #ifndef V8_BASE_ATOMICOPS_H_
 #define V8_BASE_ATOMICOPS_H_
 
 #include <stdint.h>
 
 // Small C++ header which defines implementation specific macros used to
@@ skipping 36 matching lines @@
 // Atomically execute:
 //      result = *ptr;
 //      if (*ptr == old_value)
 //        *ptr = new_value;
 //      return result;
 //
 // I.e., replace "*ptr" with "new_value" if "*ptr" used to be "old_value".
 // Always return the old value of "*ptr"
 //
 // This routine implies no memory barriers.
-Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32* ptr,
-                                  Atomic32 old_value,
-                                  Atomic32 new_value);
+Atomic32 Relaxed_CompareAndSwap(volatile Atomic32* ptr, Atomic32 old_value,
+                                Atomic32 new_value);
 
 // Atomically store new_value into *ptr, returning the previous value held in
 // *ptr.  This routine implies no memory barriers.
-Atomic32 NoBarrier_AtomicExchange(volatile Atomic32* ptr, Atomic32 new_value);
+Atomic32 Relaxed_AtomicExchange(volatile Atomic32* ptr, Atomic32 new_value);
 
 // Atomically increment *ptr by "increment".  Returns the new value of
 // *ptr with the increment applied.  This routine implies no memory barriers.
-Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32* ptr, Atomic32 increment);
+Atomic32 Relaxed_AtomicIncrement(volatile Atomic32* ptr, Atomic32 increment);
 
 Atomic32 Barrier_AtomicIncrement(volatile Atomic32* ptr,
                                  Atomic32 increment);
 
 // These following lower-level operations are typically useful only to people
 // implementing higher-level synchronization operations like spinlocks,
 // mutexes, and condition-variables.  They combine CompareAndSwap(), a load, or
 // a store with appropriate memory-ordering instructions.  "Acquire" operations
 // ensure that no later memory access can be reordered ahead of the operation.
 // "Release" operations ensure that no previous memory access can be reordered
 // after the operation.  "Barrier" operations have both "Acquire" and "Release"
 // semantics.   A MemoryBarrier() has "Barrier" semantics, but does no memory
 // access.
 Atomic32 Acquire_CompareAndSwap(volatile Atomic32* ptr,
                                 Atomic32 old_value,
                                 Atomic32 new_value);
 Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr,
                                 Atomic32 old_value,
                                 Atomic32 new_value);
 
 void MemoryBarrier();

[ulan, 2017/05/29 13:08:20]

I will rename this in another CL.

-void NoBarrier_Store(volatile Atomic8* ptr, Atomic8 value);
-void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value);
+void Relaxed_Store(volatile Atomic8* ptr, Atomic8 value);
+void Relaxed_Store(volatile Atomic32* ptr, Atomic32 value);
 void Release_Store(volatile Atomic32* ptr, Atomic32 value);
 
-Atomic8 NoBarrier_Load(volatile const Atomic8* ptr);
-Atomic32 NoBarrier_Load(volatile const Atomic32* ptr);
+Atomic8 Relaxed_Load(volatile const Atomic8* ptr);
+Atomic32 Relaxed_Load(volatile const Atomic32* ptr);
 Atomic32 Acquire_Load(volatile const Atomic32* ptr);
 
 // 64-bit atomic operations (only available on 64-bit processors).
 #ifdef V8_HOST_ARCH_64_BIT
-Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64* ptr,
-                                  Atomic64 old_value,
-                                  Atomic64 new_value);
-Atomic64 NoBarrier_AtomicExchange(volatile Atomic64* ptr, Atomic64 new_value);
-Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64* ptr, Atomic64 increment);
+Atomic64 Relaxed_CompareAndSwap(volatile Atomic64* ptr, Atomic64 old_value,
+                                Atomic64 new_value);
+Atomic64 Relaxed_AtomicExchange(volatile Atomic64* ptr, Atomic64 new_value);
+Atomic64 Relaxed_AtomicIncrement(volatile Atomic64* ptr, Atomic64 increment);
 Atomic64 Barrier_AtomicIncrement(volatile Atomic64* ptr, Atomic64 increment);

[ulan, 2017/05/29 13:08:20]

I will rename this in another CL.

 
 Atomic64 Acquire_CompareAndSwap(volatile Atomic64* ptr,
                                 Atomic64 old_value,
                                 Atomic64 new_value);
 Atomic64 Release_CompareAndSwap(volatile Atomic64* ptr,
                                 Atomic64 old_value,
                                 Atomic64 new_value);
-void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value);
+void Relaxed_Store(volatile Atomic64* ptr, Atomic64 value);
 void Release_Store(volatile Atomic64* ptr, Atomic64 value);
-Atomic64 NoBarrier_Load(volatile const Atomic64* ptr);
+Atomic64 Relaxed_Load(volatile const Atomic64* ptr);
 Atomic64 Acquire_Load(volatile const Atomic64* ptr);
 #endif  // V8_HOST_ARCH_64_BIT
 
 }  // namespace base
 }  // namespace v8
 
 #if defined(V8_OS_WIN)
 // TODO(hpayer): The MSVC header includes windows.h, which other files end up
 //               relying on. Fix this as part of crbug.com/559247.
 #include "src/base/atomicops_internals_x86_msvc.h"
 #else
 #include "src/base/atomicops_internals_portable.h"
 #endif
 
 // On some platforms we need additional declarations to make
 // AtomicWord compatible with our other Atomic* types.
 #if defined(V8_OS_MACOSX) || defined(V8_OS_OPENBSD) || defined(V8_OS_AIX)
 #include "src/base/atomicops_internals_atomicword_compat.h"
 #endif
 
 #endif  // V8_BASE_ATOMICOPS_H_