commit 70102e618a82c41c0e0c790db6959bc58d4837de
author Ulya Trafimovich <skvadrik@google.com> Fri Jan 14 15:20:38 2022 +0000
committer Ulya Trofimovich <skvadrik@google.com> Mon Jan 17 14:52:07 2022 +0000
tree 03766b8b7fe4172c7421ea863ecbf03fcdf1ecd4
parent 27d4f33f6bb07c941f9082eb1b6d920540f98370

arm64: Implement Unsafe.compareAndSetObject intrinsic.

Also fix a few copy-paste errors in comments for x86/x86_64.

The implementation is the same as Unsafe.compareAndSwapObject, as the
latter operation has compare-and-set semantics.

Benchmarks improvements (using benchmarks provided by
https://android-review.googlesource.com/1420959):

  benchmark                              before   after
  -----------------------------------------------------
  UnsafeCompareAndSetStaticFieldString   3.908    0.014
  UnsafeCompareAndSetFieldString         3.917    0.014

Bug: 71781600
Bug: 202868177
Test: art/test.py --target -r -t 712-varhandle-invocations --64
Change-Id: I799f47210f8b70d6944418c05b985fe678f36208

compiler/optimizing/intrinsics_x86.cc

diff --git a/compiler/optimizing/intrinsics_x86.cc b/compiler/optimizing/intrinsics_x86.cc
index c9c8a5a..7c25374 100644
--- a/compiler/optimizing/intrinsics_x86.cc
+++ b/compiler/optimizing/intrinsics_x86.cc
@@ -2117,12 +2117,12 @@
 }
 
 void IntrinsicLocationsBuilderX86::VisitJdkUnsafeCASInt(HInvoke* invoke) {
-  // `jdk.internal.misc.Unsafe.compareAndSwapObject` has compare-and-set semantics (see javadoc).
+  // `jdk.internal.misc.Unsafe.compareAndSwapInt` has compare-and-set semantics (see javadoc).
   VisitJdkUnsafeCompareAndSetInt(invoke);
 }
 
 void IntrinsicLocationsBuilderX86::VisitJdkUnsafeCASLong(HInvoke* invoke) {
-  // `jdk.internal.misc.Unsafe.compareAndSwapObject` has compare-and-set semantics (see javadoc).
+  // `jdk.internal.misc.Unsafe.compareAndSwapLong` has compare-and-set semantics (see javadoc).
   VisitJdkUnsafeCompareAndSetLong(invoke);
 }
 
@@ -2385,12 +2385,12 @@
 }
 
 void IntrinsicCodeGeneratorX86::VisitJdkUnsafeCASInt(HInvoke* invoke) {
-  // `jdk.internal.misc.Unsafe.compareAndSwapObject` has compare-and-set semantics (see javadoc).
+  // `jdk.internal.misc.Unsafe.compareAndSwapInt` has compare-and-set semantics (see javadoc).
   VisitJdkUnsafeCompareAndSetInt(invoke);
 }
 
 void IntrinsicCodeGeneratorX86::VisitJdkUnsafeCASLong(HInvoke* invoke) {
-  // `jdk.internal.misc.Unsafe.compareAndSwapObject` has compare-and-set semantics (see javadoc).
+  // `jdk.internal.misc.Unsafe.compareAndSwapLong` has compare-and-set semantics (see javadoc).
   VisitJdkUnsafeCompareAndSetLong(invoke);
 }