[wrapper-tracing] Force inlining of marking deque helper

third_party/WebKit/Source/platform/heap/WrapperVisitor.h

Index: third_party/WebKit/Source/platform/heap/WrapperVisitor.h
diff --git a/third_party/WebKit/Source/platform/heap/WrapperVisitor.h b/third_party/WebKit/Source/platform/heap/WrapperVisitor.h
index 13de57b4c7cbaf1471f84a9feab62df200f12f56..3e0c49b8e52a2a06960fdef4b8a371cf50e6c3f0 100644
--- a/third_party/WebKit/Source/platform/heap/WrapperVisitor.h
+++ b/third_party/WebKit/Source/platform/heap/WrapperVisitor.h
@@ -91,7 +91,7 @@ class PLATFORM_EXPORT WrapperVisitor {
 
  public:
   template <typename T>
-  static NEVER_INLINE void missedWriteBarrier() {
+  static NOINLINE void missedWriteBarrier() {

[Michael Lippautz, 2017/01/18 13:47:40]

https://cs.chromium.org/chromium/src/third_party/WebKit/Source/wtf/Compiler.h...

     NOTREACHED();
   }
 
@@ -167,7 +167,7 @@ class PLATFORM_EXPORT WrapperVisitor {
   }
 
   template <typename T>
-  void markAndPushToMarkingDeque(const T* traceable) const {
+  ALWAYS_INLINE void markAndPushToMarkingDeque(const T* traceable) const {

[Michael Lippautz, 2017/01/18 13:47:40]

The only difference in the CL responsible for the perf regression in the bug is
introduction of this small helper function.

I cannot reproduce locally, so let's try to fix this by forcing inlining (which
should make sense for this one anyways).

     if (pushToMarkingDeque(TraceTrait<T>::traceMarkedWrapper,
                            TraceTrait<T>::heapObjectHeader,
                            WrapperVisitor::missedWriteBarrier<T>, traceable)) {