New atomic operation foundation code and interfaces. Based on the atomic operations in google-perftools / tcmalloc.

- Makes atomic operations cross-platform (win/mac/linux).
- Supports 64 bit operations on 64 bit processors.
- Make atomic operations more correct on Windows (barriers).
- Introduces a better / safer interface, and abstracts away most common atomic operations, reference counting and sequence numbers.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@370 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 192 insertions, 0 deletions

diff --git a/base/atomicops_internals_x86_msvc.h b/base/atomicops_internals_x86_msvc.h
new file mode 100644
index 0000000..86f623e
--- /dev/null
+++ b/base/atomicops_internals_x86_msvc.h
@@ -0,0 +1,192 @@
+// Copyright 2008, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// This file is an internal atomic implementation, use base/atomicops.h instead.
+
+#ifndef BASE_ATOMICOPS_INTERNALS_X86_MSVC_H_
+#define BASE_ATOMICOPS_INTERNALS_X86_MSVC_H_
+
+#include <windows.h>
+
+namespace base {
+namespace subtle {
+
+inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32* ptr,
+                                         Atomic32 old_value,
+                                         Atomic32 new_value) {
+  LONG result = InterlockedCompareExchange(
+      reinterpret_cast<volatile LONG*>(ptr),
+      static_cast<LONG>(new_value),
+      static_cast<LONG>(old_value));
+  return static_cast<Atomic32>(result);
+}
+
+inline Atomic32 NoBarrier_AtomicExchange(volatile Atomic32* ptr,
+                                         Atomic32 new_value) {
+  LONG result = InterlockedExchange(
+      reinterpret_cast<volatile LONG*>(ptr),
+      static_cast<LONG>(new_value));
+  return static_cast<Atomic32>(result);
+}
+
+inline Atomic32 Barrier_AtomicIncrement(volatile Atomic32* ptr,
+                                        Atomic32 increment) {
+  return InterlockedExchangeAdd(
+      reinterpret_cast<volatile LONG*>(ptr),
+      static_cast<LONG>(increment)) + increment;
+}
+
+inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32* ptr,
+                                          Atomic32 increment) {
+  return Barrier_AtomicIncrement(ptr, increment);
+}
+
+#if !(defined(_MSC_VER) && _MSC_VER >= 1400)
+#error "We require at least vs2005 for MemoryBarrier"
+#endif
+inline void MemoryBarrier() {
+  // We use MemoryBarrier from WinNT.h
+  ::MemoryBarrier();
+}
+
+inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32* ptr,
+                                       Atomic32 old_value,
+                                       Atomic32 new_value) {
+  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
+}
+
+inline Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr,
+                                       Atomic32 old_value,
+                                       Atomic32 new_value) {
+  return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
+}
+
+inline void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value) {
+  *ptr = value;
+}
+
+inline void Acquire_Store(volatile Atomic32* ptr, Atomic32 value) {
+  NoBarrier_AtomicExchange(ptr, value);
+              // acts as a barrier in this implementation
+}
+
+inline void Release_Store(volatile Atomic32* ptr, Atomic32 value) {
+  *ptr = value; // works w/o barrier for current Intel chips as of June 2005
+  // See comments in Atomic64 version of Release_Store() below.
+}
+
+inline Atomic32 NoBarrier_Load(volatile const Atomic32* ptr) {
+  return *ptr;
+}
+
+inline Atomic32 Acquire_Load(volatile const Atomic32* ptr) {
+  Atomic32 value = *ptr;
+  return value;
+}
+
+inline Atomic32 Release_Load(volatile const Atomic32* ptr) {
+  MemoryBarrier();
+  return *ptr;
+}
+
+#if defined(_WIN64)
+
+// 64-bit low-level operations on 64-bit platform.
+
+COMPILE_ASSERT(sizeof(Atomic64) == sizeof(PVOID), atomic_word_is_atomic);
+
+inline Atomic64 NoBarrier_CompareAndSwap(volatile Atomic64* ptr,
+                                         Atomic64 old_value,
+                                         Atomic64 new_value) {
+  PVOID result = InterlockedCompareExchangePointer(
+    reinterpret_cast<volatile PVOID*>(ptr),
+    reinterpret_cast<PVOID>(new_value), reinterpret_cast<PVOID>(old_value));
+  return reinterpret_cast<Atomic64>(result);
+}
+
+inline Atomic64 NoBarrier_AtomicExchange(volatile Atomic64* ptr,
+                                         Atomic64 new_value) {
+  PVOID result = InterlockedExchangePointer(
+    reinterpret_cast<volatile PVOID*>(ptr),
+    reinterpret_cast<PVOID>(new_value));
+  return reinterpret_cast<Atomic64>(result);
+}
+
+inline Atomic64 Barrier_AtomicIncrement(volatile Atomic64* ptr,
+                                        Atomic64 increment) {
+  return InterlockedExchangeAdd64(
+      reinterpret_cast<volatile LONGLONG*>(ptr),
+      static_cast<LONGLONG>(increment)) + increment;
+}
+
+inline Atomic64 NoBarrier_AtomicIncrement(volatile Atomic64* ptr,
+                                          Atomic64 increment) {
+  return Barrier_AtomicIncrement(ptr, increment);
+}
+
+inline void NoBarrier_Store(volatile Atomic64* ptr, Atomic64 value) {
+  *ptr = value;
+}
+
+inline void Acquire_Store(volatile Atomic64* ptr, Atomic64 value) {
+  NoBarrier_AtomicExchange(ptr, value);
+              // acts as a barrier in this implementation
+}
+
+inline void Release_Store(volatile Atomic64* ptr, Atomic64 value) {
+  *ptr = value; // works w/o barrier for current Intel chips as of June 2005
+
+  // When new chips come out, check:
+  //  IA-32 Intel Architecture Software Developer's Manual, Volume 3:
+  //  System Programming Guide, Chatper 7: Multiple-processor management,
+  //  Section 7.2, Memory Ordering.
+  // Last seen at:
+  //   http://developer.intel.com/design/pentium4/manuals/index_new.htm
+}
+
+inline Atomic64 NoBarrier_Load(volatile const Atomic64* ptr) {
+  return *ptr;
+}
+
+inline Atomic64 Acquire_Load(volatile const Atomic64* ptr) {
+  Atomic64 value = *ptr;
+  return value;
+}
+
+inline Atomic64 Release_Load(volatile const Atomic64* ptr) {
+  MemoryBarrier();
+  return *ptr;
+}
+
+#endif  // defined(_WIN64)
+
+}  // namespace base::subtle
+}  // namespace base
+
+#endif  // BASE_ATOMICOPS_INTERNALS_X86_MSVC_H_