commit 629afaba488c5cfdd3ee9ba5b2df24af9de6f2a7
author Igor Murashkin <iam@google.com> Fri Feb 19 14:56:43 2016 -0800
committer Igor Murashkin <iam@google.com> Mon Mar 07 11:45:18 2016 -0800
tree e662cc005b69023ce4233ad4a5e11e3560438fce
parent 810ef3768021b5fc7b47e663e037e49c46f8c916

runtime: Add CAS and fences to sun.misc.Unsafe

Bug: 26264765
Change-Id: I68b482e5f9a0a26419af5e58a8d67c8c8a8e01a9

runtime/native/sun_misc_Unsafe.cc

diff --git a/runtime/native/sun_misc_Unsafe.cc b/runtime/native/sun_misc_Unsafe.cc
index 6ffd476..858849f 100644
--- a/runtime/native/sun_misc_Unsafe.cc
+++ b/runtime/native/sun_misc_Unsafe.cc
@@ -26,6 +26,7 @@
 #include <unistd.h>
 #include <stdlib.h>
 #include <string.h>
+#include <atomic>
 
 namespace art {
 
@@ -473,6 +474,18 @@
   obj->SetField64<false>(MemberOffset(offset), conv.converted);
 }
 
+static void Unsafe_loadFence(JNIEnv*, jobject) {
+  std::atomic_thread_fence(std::memory_order_acquire);
+}
+
+static void Unsafe_storeFence(JNIEnv*, jobject) {
+  std::atomic_thread_fence(std::memory_order_release);
+}
+
+static void Unsafe_fullFence(JNIEnv*, jobject) {
+  std::atomic_thread_fence(std::memory_order_seq_cst);
+}
+
 static JNINativeMethod gMethods[] = {
   NATIVE_METHOD(Unsafe, compareAndSwapInt, "!(Ljava/lang/Object;JII)Z"),
   NATIVE_METHOD(Unsafe, compareAndSwapLong, "!(Ljava/lang/Object;JJJ)Z"),
@@ -532,6 +545,11 @@
   OVERLOADED_NATIVE_METHOD(Unsafe, putLong, "!(JJ)V", putLongJJ),
   OVERLOADED_NATIVE_METHOD(Unsafe, putFloat, "!(JF)V", putFloatJF),
   OVERLOADED_NATIVE_METHOD(Unsafe, putDouble, "!(JD)V", putDoubleJD),
+
+  // CAS
+  NATIVE_METHOD(Unsafe, loadFence, "!()V"),
+  NATIVE_METHOD(Unsafe, storeFence, "!()V"),
+  NATIVE_METHOD(Unsafe, fullFence, "!()V"),
 };
 
 void register_sun_misc_Unsafe(JNIEnv* env) {