08b8e0ff5a
Change Heap::IterateStrongRoots to never iterate the read-only roots. In doing so remove VISIT_ALL_BUT_READ_ONLY and VISIT_ONLY_STRONG_FOR_SERIALIZATION. All such uses should now use VISIT_ALL and VISIT_ONLY_STRONG. Where ReadOnlyRoots iteration is required, this adds ReadOnlyRoots(isolate)->Iterate() at the call site. Add new begin, end, strong_mutable_roots_begin and strong_mutable_roots_end methods to RootsTable and try and make the existing uses a little more consistent. Bug: v8:8191 Change-Id: Ie9d0f9e5186db418428e2fafd38432b0bd879daa Reviewed-on: https://chromium-review.googlesource.com/c/1278500 Commit-Queue: Dan Elphick <delphick@chromium.org> Reviewed-by: Ulan Degenbaev <ulan@chromium.org> Reviewed-by: Jakob Gruber <jgruber@chromium.org> Cr-Commit-Position: refs/heads/master@{#56672}
42 lines
1.5 KiB
C++
42 lines
1.5 KiB
C++
// Copyright 2015 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#include "src/address-map.h"
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#include "src/heap/heap.h"
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#include "src/isolate.h"
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#include "src/objects-inl.h"
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namespace v8 {
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namespace internal {
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RootIndexMap::RootIndexMap(Isolate* isolate) {
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map_ = isolate->root_index_map();
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if (map_ != nullptr) return;
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map_ = new HeapObjectToIndexHashMap();
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for (RootIndex root_index = RootIndex::kFirstStrongOrReadOnlyRoot;
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root_index <= RootIndex::kLastStrongOrReadOnlyRoot; ++root_index) {
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Object* root = isolate->root(root_index);
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if (!root->IsHeapObject()) continue;
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// Omit root entries that can be written after initialization. They must
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// not be referenced through the root list in the snapshot.
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// Since we map the raw address of an root item to its root list index, the
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// raw address must be constant, i.e. the object must be immovable.
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if (RootsTable::IsImmortalImmovable(root_index)) {
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HeapObject* heap_object = HeapObject::cast(root);
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Maybe<uint32_t> maybe_index = map_->Get(heap_object);
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uint32_t index = static_cast<uint32_t>(root_index);
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if (maybe_index.IsJust()) {
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// Some are initialized to a previous value in the root list.
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DCHECK_LT(maybe_index.FromJust(), index);
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} else {
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map_->Set(heap_object, index);
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}
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}
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}
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isolate->set_root_index_map(map_);
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}
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} // namespace internal
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} // namespace v8
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