[TypeFeedbackVector] Root feedback vectors at function literal site.

src/objects-inl.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 5637 matching lines @@
                         map->unused_property_fields());
 }
 
 
 ACCESSORS(JSBoundFunction, bound_target_function, JSReceiver,
           kBoundTargetFunctionOffset)
 ACCESSORS(JSBoundFunction, bound_this, Object, kBoundThisOffset)
 ACCESSORS(JSBoundFunction, bound_arguments, FixedArray, kBoundArgumentsOffset)
 
 ACCESSORS(JSFunction, shared, SharedFunctionInfo, kSharedFunctionInfoOffset)
-ACCESSORS(JSFunction, feedback_vector, TypeFeedbackVector,
-          kFeedbackVectorOffset)
+ACCESSORS(JSFunction, feedback_vector_cell, Cell, kFeedbackVectorOffset)
 ACCESSORS(JSFunction, next_function_link, Object, kNextFunctionLinkOffset)
 
 ACCESSORS(JSGlobalObject, native_context, Context, kNativeContextOffset)
 ACCESSORS(JSGlobalObject, global_proxy, JSObject, kGlobalProxyOffset)
 
 ACCESSORS(JSGlobalProxy, native_context, Object, kNativeContextOffset)
 ACCESSORS(JSGlobalProxy, hash, Object, kHashOffset)
 
 ACCESSORS(AccessorInfo, name, Object, kNameOffset)
 SMI_ACCESSORS(AccessorInfo, flag, kFlagOffset)
@@ skipping 804 matching lines @@
 }
 
 bool SharedFunctionInfo::IsSubjectToDebugging() {
   return IsUserJavaScript() && !HasAsmWasmData();
 }
 
 bool SharedFunctionInfo::OptimizedCodeMapIsCleared() const {
   return optimized_code_map() == GetHeap()->empty_fixed_array();
 }
 
+TypeFeedbackVector* JSFunction::feedback_vector() const {
+  DCHECK(feedback_vector_cell()->value()->IsTypeFeedbackVector());
+  return TypeFeedbackVector::cast(feedback_vector_cell()->value());
+}
 
 bool JSFunction::IsOptimized() {
   return code()->kind() == Code::OPTIMIZED_FUNCTION;
 }
 
 bool JSFunction::IsInterpreted() {
   return code()->is_interpreter_trampoline_builtin();
 }
 
 bool JSFunction::IsMarkedForBaseline() {
@@ skipping 87 matching lines @@
   // context based on the state change.
   if (!was_optimized && is_optimized) {
     context()->native_context()->AddOptimizedFunction(this);
   }
   if (was_optimized && !is_optimized) {
     // TODO(titzer): linear in the number of optimized functions; fix!
     context()->native_context()->RemoveOptimizedFunction(this);
   }
 }
 
+bool JSFunction::has_feedback_vector() const {
+  SharedFunctionInfo* shared = this->shared();
+
+  return (feedback_vector_cell()->value() !=
+              shared->GetIsolate()->heap()->empty_type_feedback_vector() ||
+          (shared->feedback_metadata()->slot_count() == 0 &&
+           shared->num_literals() == 0));
+}
 
 Context* JSFunction::context() {
   return Context::cast(READ_FIELD(this, kContextOffset));
 }
 
 
 JSObject* JSFunction::global_proxy() {
   return context()->global_proxy();
 }
 
@@ skipping 1775 matching lines @@
 #undef WRITE_INT64_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_OBJECTS_INL_H_