// Copyright 2017 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.
|
|
#ifndef V8_VISITORS_H_
|
#define V8_VISITORS_H_
|
|
#include "src/globals.h"
|
|
namespace v8 {
|
namespace internal {
|
|
class CodeDataContainer;
|
class MaybeObject;
|
class Object;
|
|
#define ROOT_ID_LIST(V) \
|
V(kStringTable, "(Internalized strings)") \
|
V(kExternalStringsTable, "(External strings)") \
|
V(kStrongRootList, "(Strong roots)") \
|
V(kSmiRootList, "(Smi roots)") \
|
V(kBootstrapper, "(Bootstrapper)") \
|
V(kTop, "(Isolate)") \
|
V(kRelocatable, "(Relocatable)") \
|
V(kDebug, "(Debugger)") \
|
V(kCompilationCache, "(Compilation cache)") \
|
V(kHandleScope, "(Handle scope)") \
|
V(kDispatchTable, "(Dispatch table)") \
|
V(kBuiltins, "(Builtins)") \
|
V(kGlobalHandles, "(Global handles)") \
|
V(kEternalHandles, "(Eternal handles)") \
|
V(kThreadManager, "(Thread manager)") \
|
V(kStrongRoots, "(Strong roots)") \
|
V(kExtensions, "(Extensions)") \
|
V(kCodeFlusher, "(Code flusher)") \
|
V(kPartialSnapshotCache, "(Partial snapshot cache)") \
|
V(kWeakCollections, "(Weak collections)") \
|
V(kWrapperTracing, "(Wrapper tracing)") \
|
V(kUnknown, "(Unknown)")
|
|
class VisitorSynchronization : public AllStatic {
|
public:
|
#define DECLARE_ENUM(enum_item, ignore) enum_item,
|
enum SyncTag { ROOT_ID_LIST(DECLARE_ENUM) kNumberOfSyncTags };
|
#undef DECLARE_ENUM
|
};
|
|
enum class Root {
|
#define DECLARE_ENUM(enum_item, ignore) enum_item,
|
ROOT_ID_LIST(DECLARE_ENUM)
|
#undef DECLARE_ENUM
|
kNumberOfRoots
|
};
|
|
// Abstract base class for visiting, and optionally modifying, the
|
// pointers contained in roots. Used in GC and serialization/deserialization.
|
class RootVisitor BASE_EMBEDDED {
|
public:
|
virtual ~RootVisitor() {}
|
|
// Visits a contiguous arrays of pointers in the half-open range
|
// [start, end). Any or all of the values may be modified on return.
|
virtual void VisitRootPointers(Root root, const char* description,
|
Object** start, Object** end) = 0;
|
|
// Handy shorthand for visiting a single pointer.
|
virtual void VisitRootPointer(Root root, const char* description,
|
Object** p) {
|
VisitRootPointers(root, description, p, p + 1);
|
}
|
|
// Intended for serialization/deserialization checking: insert, or
|
// check for the presence of, a tag at this position in the stream.
|
// Also used for marking up GC roots in heap snapshots.
|
// TODO(ulan): Remove this.
|
virtual void Synchronize(VisitorSynchronization::SyncTag tag) {}
|
|
static const char* RootName(Root root);
|
};
|
|
class RelocIterator;
|
|
// Abstract base class for visiting, and optionally modifying, the
|
// pointers contained in Objects. Used in GC and serialization/deserialization.
|
class ObjectVisitor BASE_EMBEDDED {
|
public:
|
virtual ~ObjectVisitor() {}
|
|
// Visits a contiguous arrays of pointers in the half-open range
|
// [start, end). Any or all of the values may be modified on return.
|
virtual void VisitPointers(HeapObject* host, Object** start,
|
Object** end) = 0;
|
virtual void VisitPointers(HeapObject* host, MaybeObject** start,
|
MaybeObject** end) = 0;
|
|
// Handy shorthand for visiting a single pointer.
|
virtual void VisitPointer(HeapObject* host, Object** p) {
|
VisitPointers(host, p, p + 1);
|
}
|
virtual void VisitPointer(HeapObject* host, MaybeObject** p) {
|
VisitPointers(host, p, p + 1);
|
}
|
|
// To allow lazy clearing of inline caches the visitor has
|
// a rich interface for iterating over Code objects ...
|
|
// Visits a code target in the instruction stream.
|
virtual void VisitCodeTarget(Code* host, RelocInfo* rinfo);
|
|
// Visits a runtime entry in the instruction stream.
|
virtual void VisitRuntimeEntry(Code* host, RelocInfo* rinfo) {}
|
|
// Visit pointer embedded into a code object.
|
virtual void VisitEmbeddedPointer(Code* host, RelocInfo* rinfo);
|
|
// Visits an external reference embedded into a code object.
|
virtual void VisitExternalReference(Code* host, RelocInfo* rinfo) {}
|
|
// Visits an external reference.
|
virtual void VisitExternalReference(Foreign* host, Address* p) {}
|
|
// Visits an (encoded) internal reference.
|
virtual void VisitInternalReference(Code* host, RelocInfo* rinfo) {}
|
|
// Visits an off-heap target in the instruction stream.
|
virtual void VisitOffHeapTarget(Code* host, RelocInfo* rinfo) {}
|
|
// Visits the relocation info using the given iterator.
|
virtual void VisitRelocInfo(RelocIterator* it);
|
};
|
|
} // namespace internal
|
} // namespace v8
|
|
#endif // V8_VISITORS_H_
|