1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ART_RUNTIME_MIRROR_CLASS_REFVISITOR_INL_H_
18 #define ART_RUNTIME_MIRROR_CLASS_REFVISITOR_INL_H_
19 
20 #include "class-inl.h"
21 
22 #include "art_field-inl.h"
23 #include "class_ext-inl.h"
24 
25 namespace art {
26 namespace mirror {
27 
28 template <bool kVisitNativeRoots,
29           VerifyObjectFlags kVerifyFlags,
30           ReadBarrierOption kReadBarrierOption,
31           typename Visitor>
VisitReferences(ObjPtr<Class> klass,const Visitor & visitor)32 inline void Class::VisitReferences(ObjPtr<Class> klass, const Visitor& visitor) {
33   VisitInstanceFieldsReferences<kVerifyFlags, kReadBarrierOption>(klass.Ptr(), visitor);
34   // Right after a class is allocated, but not yet loaded
35   // (ClassStatus::kNotReady, see ClassLinker::LoadClass()), GC may find it
36   // and scan it. IsTemp() may call Class::GetAccessFlags() but may
37   // fail in the DCHECK in Class::GetAccessFlags() because the class
38   // status is ClassStatus::kNotReady. To avoid it, rely on IsResolved()
39   // only. This is fine because a temp class never goes into the
40   // ClassStatus::kResolved state.
41   if (IsResolved<kVerifyFlags>()) {
42     // Temp classes don't ever populate imt/vtable or static fields and they are not even
43     // allocated with the right size for those. Also, unresolved classes don't have fields
44     // linked yet.
45     VisitStaticFieldsReferences<kVerifyFlags, kReadBarrierOption>(this, visitor);
46   }
47   if (kVisitNativeRoots) {
48     // Since this class is reachable, we must also visit the associated roots when we scan it.
49     VisitNativeRoots<kReadBarrierOption>(
50         visitor, Runtime::Current()->GetClassLinker()->GetImagePointerSize());
51   }
52 }
53 
54 template<ReadBarrierOption kReadBarrierOption, class Visitor>
VisitNativeRoots(Visitor & visitor,PointerSize pointer_size)55 void Class::VisitNativeRoots(Visitor& visitor, PointerSize pointer_size) {
56   VisitFields<kReadBarrierOption>([&](ArtField* field) REQUIRES_SHARED(art::Locks::mutator_lock_) {
57     field->VisitRoots(visitor);
58     if (kIsDebugBuild && IsResolved()) {
59       CHECK_EQ(field->GetDeclaringClass<kReadBarrierOption>(), this)
60           << GetStatus() << field->GetDeclaringClass()->PrettyClass() << " != " << PrettyClass();
61     }
62   });
63   // Don't use VisitMethods because we don't want to hit the class-ext methods twice.
64   for (ArtMethod& method : GetMethods(pointer_size)) {
65     method.VisitRoots<kReadBarrierOption>(visitor, pointer_size);
66   }
67   ObjPtr<ClassExt> ext(GetExtData<kDefaultVerifyFlags, kReadBarrierOption>());
68   if (!ext.IsNull()) {
69     ext->VisitNativeRoots<kReadBarrierOption, Visitor>(visitor, pointer_size);
70   }
71 }
72 
73 template<ReadBarrierOption kReadBarrierOption, class Visitor>
VisitMethods(Visitor visitor,PointerSize pointer_size)74 void Class::VisitMethods(Visitor visitor, PointerSize pointer_size) {
75   for (ArtMethod& method : GetMethods(pointer_size)) {
76     visitor(&method);
77   }
78   ObjPtr<ClassExt> ext(GetExtData<kDefaultVerifyFlags, kReadBarrierOption>());
79   if (!ext.IsNull()) {
80     ext->VisitMethods<kReadBarrierOption, Visitor>(visitor, pointer_size);
81   }
82 }
83 
84 template<ReadBarrierOption kReadBarrierOption, class Visitor>
VisitFields(Visitor visitor)85 void Class::VisitFields(Visitor visitor) {
86   for (ArtField& sfield : GetSFieldsUnchecked()) {
87     visitor(&sfield);
88   }
89   for (ArtField& ifield : GetIFieldsUnchecked()) {
90     visitor(&ifield);
91   }
92 }
93 
94 }  // namespace mirror
95 }  // namespace art
96 
97 #endif  // ART_RUNTIME_MIRROR_CLASS_REFVISITOR_INL_H_
98