зеркало из https://github.com/mozilla/gecko-dev.git
Bug 1564313 - Update comments to // style in nursery code r=sfink
Differential Revision: https://phabricator.services.mozilla.com/D37365 --HG-- extra : moz-landing-system : lando
This commit is contained in:
Paul Bone
Родитель
624de194fe
Коммит
94ced028b9
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@ -69,7 +69,7 @@ struct NurseryChunk {
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static_assert(sizeof(js::NurseryChunk) == gc::ChunkSize,
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"Nursery chunk size must match gc::Chunk size.");
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} /* namespace js */
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} // namespace js
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inline void js::NurseryChunk::poisonAndInit(JSRuntime* rt, size_t size) {
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poisonRange(0, size, JS_FRESH_NURSERY_PATTERN, MemCheckKind::MakeUndefined);
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@ -96,7 +96,7 @@ inline void js::NurseryChunk::poisonAfterEvict(size_t extent) {
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poisonRange(0, extent, JS_SWEPT_NURSERY_PATTERN, MemCheckKind::MakeNoAccess);
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}
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/* static */
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// static
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inline js::NurseryChunk* js::NurseryChunk::fromChunk(Chunk* chunk) {
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return reinterpret_cast<NurseryChunk*>(chunk);
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}
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@ -235,10 +235,10 @@ bool js::Nursery::init(uint32_t maxNurseryBytes, AutoLockGCBgAlloc& lock) {
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maxNurseryBytes = 0;
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}
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/* maxNurseryBytes parameter is rounded down to a multiple of chunk size. */
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// maxNurseryBytes parameter is rounded down to a multiple of chunk size.
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chunkCountLimit_ = maxNurseryBytes >> ChunkShift;
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/* If no chunks are specified then the nursery is permanently disabled. */
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// If no chunks are specified then the nursery is permanently disabled.
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if (chunkCountLimit_ == 0) {
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return true;
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}
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@ -248,7 +248,7 @@ bool js::Nursery::init(uint32_t maxNurseryBytes, AutoLockGCBgAlloc& lock) {
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}
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capacity_ = roundSize(tunables().gcMinNurseryBytes());
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MOZ_ASSERT(capacity_ >= ArenaSize);
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/* After this point the Nursery has been enabled */
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// After this point the Nursery has been enabled
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setCurrentChunk(0);
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setStartPosition();
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@ -596,7 +596,7 @@ void* js::Nursery::reallocateBuffer(JSObject* obj, void* oldBuffer,
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return newBuffer;
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}
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/* The nursery cannot make use of the returned slots data. */
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// The nursery cannot make use of the returned slots data.
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if (newBytes < oldBytes) {
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return oldBuffer;
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}
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@ -682,10 +682,8 @@ inline float js::Nursery::calcPromotionRate(bool* validForTenuring) const {
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if (previousGC.nurseryUsedBytes > 0) {
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if (validForTenuring) {
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/*
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* We can only use promotion rates if they're likely to be valid,
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* they're only valid if the nursury was at least 90% full.
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*/
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// We can only use promotion rates if they're likely to be valid,
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// they're only valid if the nursury was at least 90% full.
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*validForTenuring = used > capacity * 0.9f;
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}
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rate = tenured / used;
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@ -777,7 +775,7 @@ void js::Nursery::renderProfileJSON(JSONPrinter& json) const {
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json.endObject();
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}
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/* static */
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// static
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void js::Nursery::printProfileHeader() {
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fprintf(stderr, "MinorGC: Reason PRate Size ");
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#define PRINT_HEADER(name, text) fprintf(stderr, " %6s", text);
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@ -786,7 +784,7 @@ void js::Nursery::printProfileHeader() {
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fprintf(stderr, "\n");
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}
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/* static */
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// static
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void js::Nursery::printProfileDurations(const ProfileDurations& times) {
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for (auto time : times) {
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fprintf(stderr, " %6" PRIi64, static_cast<int64_t>(time.ToMicroseconds()));
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@ -1230,10 +1228,8 @@ void js::Nursery::clear() {
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.poisonAfterEvict(position() - chunk(currentChunk_).start());
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}
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/*
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* Reset the start chunk & position if we're not in this zeal mode, or we're
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* in it and close to the end of the nursery.
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*/
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// Reset the start chunk & position if we're not in this zeal mode, or we're
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// in it and close to the end of the nursery.
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MOZ_ASSERT(maxChunkCount() > 0);
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if (!runtime()->hasZealMode(ZealMode::GenerationalGC) ||
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(runtime()->hasZealMode(ZealMode::GenerationalGC) &&
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@ -1241,7 +1237,7 @@ void js::Nursery::clear() {
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setCurrentChunk(0);
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}
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/* Set current start position for isEmpty checks. */
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// Set current start position for isEmpty checks.
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setStartPosition();
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}
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@ -1342,19 +1338,15 @@ void js::Nursery::maybeResizeNursery(JS::GCReason reason) {
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return;
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}
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/*
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* This incorrect promotion rate results in better nursery sizing
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* decisions, however we should to better tuning based on the real
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* promotion rate in the future.
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*/
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// This incorrect promotion rate results in better nursery sizing
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// decisions, however we should to better tuning based on the real
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// promotion rate in the future.
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const float promotionRate =
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float(previousGC.tenuredBytes) / float(previousGC.nurseryCapacity);
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/*
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* Object lifetimes aren't going to behave linearly, but a better
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* relationship that works for all programs and can be predicted in
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* advance doesn't exist.
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*/
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// Object lifetimes aren't going to behave linearly, but a better
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// relationship that works for all programs and can be predicted in
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// advance doesn't exist.
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static const float GrowThreshold = 0.03f;
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static const float ShrinkThreshold = 0.01f;
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static const float PromotionGoal = (GrowThreshold + ShrinkThreshold) / 2.0f;
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@ -1424,9 +1416,9 @@ bool js::Nursery::maybeResizeExact(JS::GCReason reason) {
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}
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if (newMaxNurseryChunks != chunkCountLimit_) {
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chunkCountLimit_ = newMaxNurseryChunks;
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/* The configured maximum nursery size is changing */
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// The configured maximum nursery size is changing
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if (JS_HOWMANY(capacity_, gc::ChunkSize) > newMaxNurseryChunks) {
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/* We need to shrink the nursery */
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// We need to shrink the nursery
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static_assert(NurseryChunkUsableSize < ChunkSize,
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"Usable size must be smaller than total size or this "
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"calculation might overflow");
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@ -1439,10 +1431,8 @@ bool js::Nursery::maybeResizeExact(JS::GCReason reason) {
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MOZ_ASSERT(minNurseryBytes >= ArenaSize);
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if (minNurseryBytes > capacity()) {
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/*
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* the configured minimum nursery size is changing and we need to grow the
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* nursery
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*/
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// the configured minimum nursery size is changing and we need to grow the
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// nursery
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MOZ_ASSERT(minNurseryBytes <= roundSize(tunables().gcMaxNurseryBytes()));
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growAllocableSpace(minNurseryBytes);
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return true;
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@ -67,7 +67,7 @@ class RelocationOverlay;
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struct TenureCountCache;
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enum class AllocKind : uint8_t;
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class TenuredCell;
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} /* namespace gc */
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} // namespace gc
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namespace jit {
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class MacroAssembler;
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@ -151,13 +151,11 @@ class TenuringTracer : public JSTracer {
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void traceSlots(JS::Value* vp, JS::Value* end);
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};
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/*
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* Classes with JSCLASS_SKIP_NURSERY_FINALIZE or Wrapper classes with
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* CROSS_COMPARTMENT flags will not have their finalizer called if they are
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* nursery allocated and not promoted to the tenured heap. The finalizers for
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* these classes must do nothing except free data which was allocated via
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* Nursery::allocateBuffer.
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*/
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// Classes with JSCLASS_SKIP_NURSERY_FINALIZE or Wrapper classes with
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// CROSS_COMPARTMENT flags will not have their finalizer called if they are
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// nursery allocated and not promoted to the tenured heap. The finalizers for
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// these classes must do nothing except free data which was allocated via
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// Nursery::allocateBuffer.
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inline bool CanNurseryAllocateFinalizedClass(const js::Class* const clasp) {
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MOZ_ASSERT(clasp->hasFinalize());
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return clasp->flags & JSCLASS_SKIP_NURSERY_FINALIZE;
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@ -168,9 +166,7 @@ class Nursery {
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static const size_t Alignment = gc::ChunkSize;
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static const size_t ChunkShift = gc::ChunkShift;
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/*
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* SubChunkStep is the minimum amount to adjust the nursery's size by.
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*/
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// SubChunkStep is the minimum amount to adjust the nursery's size by.
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static const size_t SubChunkStep = gc::ArenaSize;
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struct alignas(gc::CellAlignBytes) CellAlignedByte {
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@ -213,13 +209,11 @@ class Nursery {
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void disableStrings();
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bool canAllocateStrings() const { return canAllocateStrings_; }
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/* Return true if no allocations have been made since the last collection. */
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// Return true if no allocations have been made since the last collection.
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bool isEmpty() const;
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/*
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* Check whether an arbitrary pointer is within the nursery. This is
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* slower than IsInsideNursery(Cell*), but works on all types of pointers.
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*/
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// Check whether an arbitrary pointer is within the nursery. This is
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// slower than IsInsideNursery(Cell*), but works on all types of pointers.
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MOZ_ALWAYS_INLINE bool isInside(gc::Cell* cellp) const = delete;
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MOZ_ALWAYS_INLINE bool isInside(const void* p) const {
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for (auto chunk : chunks_) {
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@ -233,22 +227,16 @@ class Nursery {
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template <typename T>
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inline bool isInside(const SharedMem<T>& p) const;
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/*
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* Allocate and return a pointer to a new GC object with its |slots|
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* pointer pre-filled. Returns nullptr if the Nursery is full.
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*/
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// Allocate and return a pointer to a new GC object with its |slots|
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// pointer pre-filled. Returns nullptr if the Nursery is full.
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JSObject* allocateObject(JSContext* cx, size_t size, size_t numDynamic,
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const js::Class* clasp);
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/*
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* Allocate and return a pointer to a new string. Returns nullptr if the
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* Nursery is full.
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*/
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// Allocate and return a pointer to a new string. Returns nullptr if the
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// Nursery is full.
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gc::Cell* allocateString(JS::Zone* zone, size_t size, gc::AllocKind kind);
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/*
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* String zones are stored just before the string in nursery memory.
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*/
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// String zones are stored just before the string in nursery memory.
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static JS::Zone* getStringZone(const JSString* str) {
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#ifdef DEBUG
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auto cell = reinterpret_cast<const js::gc::Cell*>(
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@ -264,59 +252,50 @@ class Nursery {
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static size_t stringHeaderSize() { return offsetof(StringLayout, cell); }
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/* Allocate a buffer for a given zone, using the nursery if possible. */
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// Allocate a buffer for a given zone, using the nursery if possible.
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void* allocateBuffer(JS::Zone* zone, size_t nbytes);
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/*
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* Allocate a buffer for a given object, using the nursery if possible and
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* obj is in the nursery.
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*/
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// Allocate a buffer for a given object, using the nursery if possible and
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// obj is in the nursery.
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void* allocateBuffer(JSObject* obj, size_t nbytes);
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/*
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* Allocate a buffer for a given object, always using the nursery if obj is
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* in the nursery. The requested size must be less than or equal to
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* MaxNurseryBufferSize.
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*/
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// Allocate a buffer for a given object, always using the nursery if obj is
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// in the nursery. The requested size must be less than or equal to
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// MaxNurseryBufferSize.
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void* allocateBufferSameLocation(JSObject* obj, size_t nbytes);
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/* Allocate a zero-initialized buffer for a given zone, using the nursery if
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* possible. If the buffer isn't allocated in the nursery, the given arena is
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* used.
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*/
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// Allocate a zero-initialized buffer for a given zone, using the nursery if
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// possible. If the buffer isn't allocated in the nursery, the given arena is
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// used.
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void* allocateZeroedBuffer(JS::Zone* zone, size_t nbytes,
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arena_id_t arena = js::MallocArena);
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/*
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* Allocate a zero-initialized buffer for a given object, using the nursery if
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* possible and obj is in the nursery. If the buffer isn't allocated in the
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* nursery, the given arena is used.
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*/
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// Allocate a zero-initialized buffer for a given object, using the nursery if
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// possible and obj is in the nursery. If the buffer isn't allocated in the
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// nursery, the given arena is used.
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void* allocateZeroedBuffer(JSObject* obj, size_t nbytes,
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arena_id_t arena = js::MallocArena);
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/* Resize an existing object buffer. */
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// Resize an existing object buffer.
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void* reallocateBuffer(JSObject* obj, void* oldBuffer, size_t oldBytes,
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size_t newBytes);
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/* Free an object buffer. */
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// Free an object buffer.
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void freeBuffer(void* buffer);
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/* The maximum number of bytes allowed to reside in nursery buffers. */
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// The maximum number of bytes allowed to reside in nursery buffers.
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static const size_t MaxNurseryBufferSize = 1024;
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/* Do a minor collection. */
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// Do a minor collection.
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void collect(JS::GCReason reason);
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/*
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* If the thing at |*ref| in the Nursery has been forwarded, set |*ref| to
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* the new location and return true. Otherwise return false and leave
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* |*ref| unset.
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*/
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// If the thing at |*ref| in the Nursery has been forwarded, set |*ref| to
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// the new location and return true. Otherwise return false and leave
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// |*ref| unset.
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MOZ_ALWAYS_INLINE MOZ_MUST_USE static bool getForwardedPointer(
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js::gc::Cell** ref);
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/* Forward a slots/elements pointer stored in an Ion frame. */
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// Forward a slots/elements pointer stored in an Ion frame.
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void forwardBufferPointer(HeapSlot** pSlotsElems);
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inline void maybeSetForwardingPointer(JSTracer* trc, void* oldData,
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@ -324,14 +303,12 @@ class Nursery {
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inline void setForwardingPointerWhileTenuring(void* oldData, void* newData,
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bool direct);
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/*
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* Register a malloced buffer that is held by a nursery object, which
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* should be freed at the end of a minor GC. Buffers are unregistered when
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* their owning objects are tenured.
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*/
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// Register a malloced buffer that is held by a nursery object, which
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// should be freed at the end of a minor GC. Buffers are unregistered when
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// their owning objects are tenured.
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bool registerMallocedBuffer(void* buffer);
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/* Mark a malloced buffer as no longer needing to be freed. */
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// Mark a malloced buffer as no longer needing to be freed.
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void removeMallocedBuffer(void* buffer) {
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MOZ_ASSERT(mallocedBuffers.has(buffer));
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mallocedBuffers.remove(buffer);
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@ -387,13 +364,13 @@ class Nursery {
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void leaveZealMode();
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#endif
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/* Write profile time JSON on JSONPrinter. */
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// Write profile time JSON on JSONPrinter.
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void renderProfileJSON(JSONPrinter& json) const;
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/* Print header line for profile times. */
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// Print header line for profile times.
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static void printProfileHeader();
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/* Print total profile times on shutdown. */
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// Print total profile times on shutdown.
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void printTotalProfileTimes();
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void* addressOfPosition() const { return (void**)&position_; }
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@ -427,7 +404,7 @@ class Nursery {
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return setsWithNurseryMemory_.append(obj);
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}
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/* The amount of space in the mapped nursery available to allocations. */
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// The amount of space in the mapped nursery available to allocations.
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static const size_t NurseryChunkUsableSize =
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gc::ChunkSize - gc::ChunkTrailerSize;
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@ -436,66 +413,56 @@ class Nursery {
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private:
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JSRuntime* runtime_;
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/* Vector of allocated chunks to allocate from. */
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// Vector of allocated chunks to allocate from.
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Vector<NurseryChunk*, 0, SystemAllocPolicy> chunks_;
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/* Pointer to the first unallocated byte in the nursery. */
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// Pointer to the first unallocated byte in the nursery.
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uintptr_t position_;
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/*
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* These fields refer to the beginning of the nursery. They're normally 0
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* and chunk(0).start() respectively. Except when a generational GC zeal
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* mode is active, then they may be arbitrary (see Nursery::clear()).
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*/
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// These fields refer to the beginning of the nursery. They're normally 0
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// and chunk(0).start() respectively. Except when a generational GC zeal
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// mode is active, then they may be arbitrary (see Nursery::clear()).
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unsigned currentStartChunk_;
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uintptr_t currentStartPosition_;
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/* Pointer to the last byte of space in the current chunk. */
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// Pointer to the last byte of space in the current chunk.
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uintptr_t currentEnd_;
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/*
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* Pointer to the last byte of space in the current chunk, or nullptr if we
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* are not allocating strings in the nursery.
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*/
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// Pointer to the last byte of space in the current chunk, or nullptr if we
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// are not allocating strings in the nursery.
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uintptr_t currentStringEnd_;
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/* The index of the chunk that is currently being allocated from. */
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// The index of the chunk that is currently being allocated from.
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unsigned currentChunk_;
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/*
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* The current nursery capacity measured in bytes. It may grow up to this
|
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* value without a collection, allocating chunks on demand. This limit may be
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* changed by maybeResizeNursery() each collection. It does not include chunk
|
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* trailers.
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*/
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// The current nursery capacity measured in bytes. It may grow up to this
|
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// value without a collection, allocating chunks on demand. This limit may be
|
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// changed by maybeResizeNursery() each collection. It does not include chunk
|
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// trailers.
|
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size_t capacity_;
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/*
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* This limit is fixed by configuration. It represents the maximum size
|
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* the nursery is permitted to tune itself to in maybeResizeNursery();
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*/
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// This limit is fixed by configuration. It represents the maximum size
|
||||
// the nursery is permitted to tune itself to in maybeResizeNursery();
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unsigned chunkCountLimit_;
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mozilla::TimeDuration timeInChunkAlloc_;
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/* Report minor collections taking at least this long, if enabled. */
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// Report minor collections taking at least this long, if enabled.
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mozilla::TimeDuration profileThreshold_;
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||||
bool enableProfiling_;
|
||||
|
||||
/* Whether we will nursery-allocate strings. */
|
||||
// Whether we will nursery-allocate strings.
|
||||
bool canAllocateStrings_;
|
||||
|
||||
/* Report ObjectGroups with at least this many instances tenured. */
|
||||
// Report ObjectGroups with at least this many instances tenured.
|
||||
int64_t reportTenurings_;
|
||||
|
||||
/*
|
||||
* Whether and why a collection of this nursery has been requested. This is
|
||||
* mutable as it is set by the store buffer, which otherwise cannot modify
|
||||
* anything in the nursery.
|
||||
*/
|
||||
// Whether and why a collection of this nursery has been requested. This is
|
||||
// mutable as it is set by the store buffer, which otherwise cannot modify
|
||||
// anything in the nursery.
|
||||
mutable JS::GCReason minorGCTriggerReason_;
|
||||
|
||||
/* Profiling data. */
|
||||
// Profiling data.
|
||||
|
||||
enum class ProfileKey {
|
||||
#define DEFINE_TIME_KEY(name, text) name,
|
||||
|
|
@ -524,56 +491,46 @@ class Nursery {
|
|||
size_t tenuredCells = 0;
|
||||
} previousGC;
|
||||
|
||||
/*
|
||||
* Calculate the promotion rate of the most recent minor GC.
|
||||
* The valid_for_tenuring parameter is used to return whether this
|
||||
* promotion rate is accurate enough (the nursery was full enough) to be
|
||||
* used for tenuring and other decisions.
|
||||
*
|
||||
* Must only be called if the previousGC data is initialised.
|
||||
*/
|
||||
// Calculate the promotion rate of the most recent minor GC.
|
||||
// The valid_for_tenuring parameter is used to return whether this
|
||||
// promotion rate is accurate enough (the nursery was full enough) to be
|
||||
// used for tenuring and other decisions.
|
||||
//
|
||||
// Must only be called if the previousGC data is initialised.
|
||||
float calcPromotionRate(bool* validForTenuring) const;
|
||||
|
||||
/*
|
||||
* The set of externally malloced buffers potentially kept live by objects
|
||||
* stored in the nursery. Any external buffers that do not belong to a
|
||||
* tenured thing at the end of a minor GC must be freed.
|
||||
*/
|
||||
// The set of externally malloced buffers potentially kept live by objects
|
||||
// stored in the nursery. Any external buffers that do not belong to a
|
||||
// tenured thing at the end of a minor GC must be freed.
|
||||
BufferSet mallocedBuffers;
|
||||
|
||||
/*
|
||||
* During a collection most hoisted slot and element buffers indicate their
|
||||
* new location with a forwarding pointer at the base. This does not work
|
||||
* for buffers whose length is less than pointer width, or when different
|
||||
* buffers might overlap each other. For these, an entry in the following
|
||||
* table is used.
|
||||
*/
|
||||
// During a collection most hoisted slot and element buffers indicate their
|
||||
// new location with a forwarding pointer at the base. This does not work
|
||||
// for buffers whose length is less than pointer width, or when different
|
||||
// buffers might overlap each other. For these, an entry in the following
|
||||
// table is used.
|
||||
typedef HashMap<void*, void*, PointerHasher<void*>, SystemAllocPolicy>
|
||||
ForwardedBufferMap;
|
||||
ForwardedBufferMap forwardedBuffers;
|
||||
|
||||
/*
|
||||
* When we assign a unique id to cell in the nursery, that almost always
|
||||
* means that the cell will be in a hash table, and thus, held live,
|
||||
* automatically moving the uid from the nursery to its new home in
|
||||
* tenured. It is possible, if rare, for an object that acquired a uid to
|
||||
* be dead before the next collection, in which case we need to know to
|
||||
* remove it when we sweep.
|
||||
*
|
||||
* Note: we store the pointers as Cell* here, resulting in an ugly cast in
|
||||
* sweep. This is because this structure is used to help implement
|
||||
* stable object hashing and we have to break the cycle somehow.
|
||||
*/
|
||||
// When we assign a unique id to cell in the nursery, that almost always
|
||||
// means that the cell will be in a hash table, and thus, held live,
|
||||
// automatically moving the uid from the nursery to its new home in
|
||||
// tenured. It is possible, if rare, for an object that acquired a uid to
|
||||
// be dead before the next collection, in which case we need to know to
|
||||
// remove it when we sweep.
|
||||
//
|
||||
// Note: we store the pointers as Cell* here, resulting in an ugly cast in
|
||||
// sweep. This is because this structure is used to help implement
|
||||
// stable object hashing and we have to break the cycle somehow.
|
||||
using CellsWithUniqueIdVector = Vector<gc::Cell*, 8, SystemAllocPolicy>;
|
||||
CellsWithUniqueIdVector cellsWithUid_;
|
||||
|
||||
using NativeObjectVector = Vector<NativeObject*, 0, SystemAllocPolicy>;
|
||||
NativeObjectVector dictionaryModeObjects_;
|
||||
|
||||
/*
|
||||
* Lists of map and set objects allocated in the nursery or with iterators
|
||||
* allocated there. Such objects need to be swept after minor GC.
|
||||
*/
|
||||
// Lists of map and set objects allocated in the nursery or with iterators
|
||||
// allocated there. Such objects need to be swept after minor GC.
|
||||
Vector<MapObject*, 0, SystemAllocPolicy> mapsWithNurseryMemory_;
|
||||
Vector<SetObject*, 0, SystemAllocPolicy> setsWithNurseryMemory_;
|
||||
|
||||
|
|
@ -586,13 +543,11 @@ class Nursery {
|
|||
|
||||
NurseryChunk& chunk(unsigned index) const { return *chunks_[index]; }
|
||||
|
||||
/*
|
||||
* Set the current chunk. This updates the currentChunk_, position_
|
||||
* currentEnd_ and currentStringEnd_ values as approprite. It'll also
|
||||
* poison the chunk, either a portion of the chunk if it is already the
|
||||
* current chunk, or the whole chunk if fullPoison is true or it is not
|
||||
* the current chunk.
|
||||
*/
|
||||
// Set the current chunk. This updates the currentChunk_, position_
|
||||
// currentEnd_ and currentStringEnd_ values as approprite. It'll also
|
||||
// poison the chunk, either a portion of the chunk if it is already the
|
||||
// current chunk, or the whole chunk if fullPoison is true or it is not
|
||||
// the current chunk.
|
||||
void setCurrentChunk(unsigned chunkno);
|
||||
|
||||
// extent is advisory, it will be ignored in sub-chunk and generational zeal
|
||||
|
|
@ -602,10 +557,8 @@ class Nursery {
|
|||
void setCurrentEnd();
|
||||
void setStartPosition();
|
||||
|
||||
/*
|
||||
* Allocate the next chunk, or the first chunk for initialization.
|
||||
* Callers will probably want to call setCurrentChunk(0) next.
|
||||
*/
|
||||
// Allocate the next chunk, or the first chunk for initialization.
|
||||
// Callers will probably want to call setCurrentChunk(0) next.
|
||||
MOZ_MUST_USE bool allocateNextChunk(unsigned chunkno,
|
||||
AutoLockGCBgAlloc& lock);
|
||||
|
||||
|
|
@ -620,7 +573,7 @@ class Nursery {
|
|||
|
||||
const js::gc::GCSchedulingTunables& tunables() const;
|
||||
|
||||
/* Common internal allocator function. */
|
||||
// Common internal allocator function.
|
||||
void* allocate(size_t size);
|
||||
|
||||
void doCollection(JS::GCReason reason, gc::TenureCountCache& tenureCounts);
|
||||
|
|
@ -628,14 +581,12 @@ class Nursery {
|
|||
float doPretenuring(JSRuntime* rt, JS::GCReason reason,
|
||||
gc::TenureCountCache& tenureCounts);
|
||||
|
||||
/*
|
||||
* Move the object at |src| in the Nursery to an already-allocated cell
|
||||
* |dst| in Tenured.
|
||||
*/
|
||||
// Move the object at |src| in the Nursery to an already-allocated cell
|
||||
// |dst| in Tenured.
|
||||
void collectToFixedPoint(TenuringTracer& trc,
|
||||
gc::TenureCountCache& tenureCounts);
|
||||
|
||||
/* Handle relocation of slots/elements pointers stored in Ion frames. */
|
||||
// Handle relocation of slots/elements pointers stored in Ion frames.
|
||||
inline void setForwardingPointer(void* oldData, void* newData, bool direct);
|
||||
|
||||
inline void setDirectForwardingPointer(void* oldData, void* newData);
|
||||
|
|
@ -647,22 +598,18 @@ class Nursery {
|
|||
ObjectElements* newHeader,
|
||||
uint32_t capacity);
|
||||
|
||||
/*
|
||||
* Updates pointers to nursery objects that have been tenured and discards
|
||||
* pointers to objects that have been freed.
|
||||
*/
|
||||
// Updates pointers to nursery objects that have been tenured and discards
|
||||
// pointers to objects that have been freed.
|
||||
void sweep(JSTracer* trc);
|
||||
|
||||
/*
|
||||
* Reset the current chunk and position after a minor collection. Also poison
|
||||
* the nursery on debug & nightly builds.
|
||||
*/
|
||||
// Reset the current chunk and position after a minor collection. Also poison
|
||||
// the nursery on debug & nightly builds.
|
||||
void clear();
|
||||
|
||||
void sweepDictionaryModeObjects();
|
||||
void sweepMapAndSetObjects();
|
||||
|
||||
/* Change the allocable space provided by the nursery. */
|
||||
// Change the allocable space provided by the nursery.
|
||||
void maybeResizeNursery(JS::GCReason reason);
|
||||
bool maybeResizeExact(JS::GCReason reason);
|
||||
size_t roundSize(size_t size) const;
|
||||
|
|
@ -674,7 +621,7 @@ class Nursery {
|
|||
// vector. Shrinks the vector but does not update maxChunkCount().
|
||||
void freeChunksFrom(unsigned firstFreeChunk);
|
||||
|
||||
/* Profile recording and printing. */
|
||||
// Profile recording and printing.
|
||||
void maybeClearProfileDurations();
|
||||
void startProfile(ProfileKey key);
|
||||
void endProfile(ProfileKey key);
|
||||
|
|
@ -686,6 +633,6 @@ class Nursery {
|
|||
friend struct NurseryChunk;
|
||||
};
|
||||
|
||||
} /* namespace js */
|
||||
} // namespace js
|
||||
|
||||
#endif /* gc_Nursery_h */
|
||||
#endif // gc_Nursery_h
|
||||
|
|
|
|||
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