commit 1fb463e42cf1d67595cff66d19c0f99e3046f4c4
author Mathieu Chartier <mathieuc@google.com> Thu Oct 23 16:48:06 2014 -0700
committer Mathieu Chartier <mathieuc@google.com> Mon Oct 27 15:05:03 2014 -0700
tree 0156d91d7881d9e5b63118dd090688b2f88c8a5b
parent 0133ec454d8dd3fa5ffe35649b5704aa18f15a49

Optimize method linking

Added more inlining, removed imt array allocation and replaced it
with a handle scope. Removed some un-necessary handle scopes.

Added logic to base interface method tables from the superclass so
that we dont need to reconstruct for every interface (large win).

Facebook launch Dalvik KK MR2:
TotalTime: 3165
TotalTime: 3652
TotalTime: 3143
TotalTime: 3298
TotalTime: 3212
TotalTime: 3211

Facebook launch TOT before:
WaitTime: 3702
WaitTime: 3616
WaitTime: 3616
WaitTime: 3687
WaitTime: 3742
WaitTime: 3767

After optimizations:
WaitTime: 2903
WaitTime: 2953
WaitTime: 2918
WaitTime: 2940
WaitTime: 2879
WaitTime: 2792

LinkInterfaceMethods no longer one of the hottest methods, new list:
4.73% art::ClassLinker::LinkVirtualMethods(art::Thread*, art::Handle<art::mirror::Class>)
3.07% art::DexFile::FindClassDef(char const*) const
2.94% art::mirror::Class::FindDeclaredStaticField(art::mirror::DexCache const*, unsigned int)
2.90% art::DexFile::FindStringId(char const*) const

Bug: 18054905
Bug: 16828525

Change-Id: I27cc70178fd3655fbe5a3178887fcba189d21321

runtime/class_linker.h

diff --git a/runtime/class_linker.h b/runtime/class_linker.h
index 107a4b2..3afbac0 100644
--- a/runtime/class_linker.h
+++ b/runtime/class_linker.h
@@ -51,6 +51,7 @@
 template<class T> class ObjectLock;
 class ScopedObjectAccessAlreadyRunnable;
 template<class T> class Handle;
+template<size_t kNumReferences> class PACKED(4) StackHandleScope;
 
 typedef bool (ClassVisitor)(mirror::Class* c, void* arg);
 
@@ -513,14 +514,16 @@
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkMethods(Thread* self, Handle<mirror::Class> klass,
-                   Handle<mirror::ObjectArray<mirror::Class>> interfaces)
+                   Handle<mirror::ObjectArray<mirror::Class>> interfaces,
+                   StackHandleScope<mirror::Class::kImtSize>* out_imt)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkVirtualMethods(Thread* self, Handle<mirror::Class> klass)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  bool LinkInterfaceMethods(Handle<mirror::Class> klass,
-                            Handle<mirror::ObjectArray<mirror::Class>> interfaces)
+  bool LinkInterfaceMethods(Thread* const self, Handle<mirror::Class> klass,
+                            Handle<mirror::ObjectArray<mirror::Class>> interfaces,
+                            StackHandleScope<mirror::Class::kImtSize>* out_imt)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   bool LinkStaticFields(Handle<mirror::Class> klass, size_t* class_size)
@@ -734,7 +737,8 @@
   };
   GcRoot<mirror::ObjectArray<mirror::Class>> class_roots_;
 
-  mirror::Class* GetClassRoot(ClassRoot class_root) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
+  ALWAYS_INLINE mirror::Class* GetClassRoot(ClassRoot class_root)
+      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   void SetClassRoot(ClassRoot class_root, mirror::Class* klass)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);