Bug Summary

File:var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h
Warning:line 268, column 7
Excessive padding in 'class js::gc::GCRuntime' (82 padding bytes, where 2 is optimal). Optimal fields order: rt, numActiveZoneIters, queuePos, lastLastDitchTime, systemZone, sharedAtomsZone_, delayedMarkingList, markLaterArenas, helperThreadRatio, maxHelperThreads, helperThreadCount, maxMarkingThreads, markingThreadCount, maxParallelThreads, dispatchedParallelTasks, createBudgetCallback, nextCellUniqueId_, verifyPreData, lastGCStartTime_, lastGCEndTime_, initialized, minorGCNumber, majorGCNumber, number, sliceNumber, reservedMarkingThreads, sweepGroups, currentSweepGroup, sweepActions, sweepZone, foregroundFinalizedZone, zonesCompacted, relocatedArenasToRelease, markingValidator, defaultTimeBudgetMS_, maybeMarkStackLimit, inPageLoadCount, lastAllocRateUpdateTime, collectorTimeSinceAllocRateUpdate, permanentAtoms, permanentWellKnownSymbols, emptyChunks_, availableChunks_, fullChunks_, backgroundSweepZones, zonesToMaybeCompact, gcCallback, gcDoCycleCollectionCallback, tenuredCallback, hostCleanupFinalizationRegistryCallback, grayRootTracer, stringStats, heapSize, queuedParallelTasks, weakCachesToSweep, markers, sweepingTracer, rootsHash, buffersToFreeAfterMinorGC, cellsToAssertNotGray, atomMarking, testMarkQueue, mainThreadContext, zones_, selectedForMarking, lock, storeBufferLock, delayedMarkingLock, maybeAtomsToSweep, sweepTask, freeTask, decommitTask, lifoBlocksToFree, lifoBlocksToFreeAfterFullMinorGC, lifoBlocksToFreeAfterNextMinorGC, finalizeCallbacks, updateWeakPointerZonesCallbacks, updateWeakPointerCompartmentCallbacks, nurseryCollectionCallbacks, blackRootTracers, allocTask, markTask, unmarkTask, tunables, storeBuffer_, foregroundFinalizedArenas, nursery_, stats_, schedulingState, numArenasFreeCommitted, majorGCTriggerReason, heapState_, minEmptyChunkCount_, maxEmptyChunkCount_, initialReason, incrementalState, initialState, sweepGroupIndex, sweepMarkResult, zealModeBits, zealFrequency, nextScheduled, zealSliceBudget, gcCallbackDepth, maybeGcOptions, delayedMarkingWorkAdded, fullGCRequested, incrementalGCEnabled, perZoneGCEnabled, cleanUpEverything, grayBitsValid, isIncremental, isFull, isCompacting, useParallelMarking, useZeal, lastMarkSlice, safeToYield, markOnBackgroundThreadDuringSweeping, useBackgroundThreads, haveDiscardedJITCodeThisSlice, hadShutdownGC, requestSliceAfterBackgroundTask, sweepAllocKind, abortSweepAfterCurrentGroup, foregroundFinalizedAllocKind, queueMarkColor, startedCompacting, compactingEnabled, nurseryEnabled, parallelMarkingEnabled, rootsRemoved, deterministicOnly, fullCompartmentChecks, alwaysPreserveCode, lowMemoryState, consider reordering the fields or adding explicit padding members

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name Unified_cpp_js_src_frontend1.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -mframe-pointer=all -relaxed-aliasing -ffp-contract=off -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/js/src/frontend -fcoverage-compilation-dir=/var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/js/src/frontend -resource-dir /usr/lib/llvm-18/lib/clang/18 -include /var/lib/jenkins/workspace/firefox-scan-build/config/gcc_hidden.h -include /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/mozilla-config.h -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/stl_wrappers -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/system_wrappers -U _FORTIFY_SOURCE -D _FORTIFY_SOURCE=2 -D DEBUG=1 -D WASM_SUPPORTS_HUGE_MEMORY -D JS_CACHEIR_SPEW -D JS_STRUCTURED_SPEW -D JS_HAS_CTYPES -D FFI_BUILDING -D EXPORT_JS_API -D MOZ_HAS_MOZGLUE -D MOZ_SUPPORT_LEAKCHECKING -I /var/lib/jenkins/workspace/firefox-scan-build/js/src/frontend -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/js/src/frontend -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/js/src -I /var/lib/jenkins/workspace/firefox-scan-build/js/src -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/nspr -I /var/lib/jenkins/workspace/firefox-scan-build/obj-x86_64-pc-linux-gnu/dist/include/nss -D MOZILLA_CLIENT -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/c++/14 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/x86_64-linux-gnu/c++/14 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../include/c++/14/backward -internal-isystem /usr/lib/llvm-18/lib/clang/18/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/14/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wno-error=tautological-type-limit-compare -Wno-invalid-offsetof -Wno-range-loop-analysis -Wno-deprecated-anon-enum-enum-conversion -Wno-deprecated-enum-enum-conversion -Wno-deprecated-this-capture -Wno-inline-new-delete -Wno-error=deprecated-declarations -Wno-error=array-bounds -Wno-error=free-nonheap-object -Wno-error=atomic-alignment -Wno-error=deprecated-builtins -Wno-psabi -Wno-error=builtin-macro-redefined -Wno-vla-cxx-extension -Wno-unknown-warning-option -fdeprecated-macro -ferror-limit 19 -stack-protector 2 -fstack-clash-protection -ftrivial-auto-var-init=pattern -fno-rtti -fgnuc-version=4.2.1 -fno-aligned-allocation -vectorize-loops -vectorize-slp -analyzer-checker optin.performance.Padding -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2024-07-30-004816-4182763-1 -x c++ Unified_cpp_js_src_frontend1.cpp
1/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
2 * vim: set ts=8 sts=2 et sw=2 tw=80:
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7#ifndef gc_GCRuntime_h
8#define gc_GCRuntime_h
9
10#include "mozilla/Atomics.h"
11#include "mozilla/DoublyLinkedList.h"
12#include "mozilla/EnumSet.h"
13#include "mozilla/Maybe.h"
14#include "mozilla/TimeStamp.h"
15
16#include "gc/ArenaList.h"
17#include "gc/AtomMarking.h"
18#include "gc/GCContext.h"
19#include "gc/GCMarker.h"
20#include "gc/GCParallelTask.h"
21#include "gc/IteratorUtils.h"
22#include "gc/Nursery.h"
23#include "gc/Scheduling.h"
24#include "gc/Statistics.h"
25#include "gc/StoreBuffer.h"
26#include "js/friend/PerformanceHint.h"
27#include "js/GCAnnotations.h"
28#include "js/UniquePtr.h"
29#include "vm/AtomsTable.h"
30
31namespace js {
32
33class AutoLockGC;
34class AutoLockGCBgAlloc;
35class AutoLockHelperThreadState;
36class FinalizationRegistryObject;
37class FinalizationRecordObject;
38class FinalizationQueueObject;
39class GlobalObject;
40class VerifyPreTracer;
41class WeakRefObject;
42
43namespace gc {
44
45using BlackGrayEdgeVector = Vector<TenuredCell*, 0, SystemAllocPolicy>;
46using ZoneVector = Vector<JS::Zone*, 4, SystemAllocPolicy>;
47
48class AutoCallGCCallbacks;
49class AutoGCSession;
50class AutoHeapSession;
51class AutoTraceSession;
52struct FinalizePhase;
53class MarkingValidator;
54struct MovingTracer;
55class ParallelMarkTask;
56enum class ShouldCheckThresholds;
57class SweepGroupsIter;
58
59// Interface to a sweep action.
60struct SweepAction {
61 // The arguments passed to each action.
62 struct Args {
63 GCRuntime* gc;
64 JS::GCContext* gcx;
65 JS::SliceBudget& budget;
66 };
67
68 virtual ~SweepAction() = default;
69 virtual IncrementalProgress run(Args& state) = 0;
70 virtual void assertFinished() const = 0;
71 virtual bool shouldSkip() { return false; }
72};
73
74class ChunkPool {
75 TenuredChunk* head_;
76 size_t count_;
77
78 public:
79 ChunkPool() : head_(nullptr), count_(0) {}
80 ChunkPool(const ChunkPool& other) = delete;
81 ChunkPool(ChunkPool&& other) { *this = std::move(other); }
82
83 ~ChunkPool() {
84 MOZ_ASSERT(!head_)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(!head_)>::isValid, "invalid assertion condition")
; if ((__builtin_expect(!!(!(!!(!head_))), 0))) { do { } while
(false); MOZ_ReportAssertionFailure("!head_", "/var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h"
, 84); AnnotateMozCrashReason("MOZ_ASSERT" "(" "!head_" ")");
do { *((volatile int*)__null) = 84; __attribute__((nomerge))
::abort(); } while (false); } } while (false);
85 MOZ_ASSERT(count_ == 0)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(count_ == 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(count_ == 0))), 0))) { do { }
while (false); MOZ_ReportAssertionFailure("count_ == 0", "/var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h"
, 85); AnnotateMozCrashReason("MOZ_ASSERT" "(" "count_ == 0" ")"
); do { *((volatile int*)__null) = 85; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false);
86 }
87
88 ChunkPool& operator=(const ChunkPool& other) = delete;
89 ChunkPool& operator=(ChunkPool&& other) {
90 head_ = other.head_;
91 other.head_ = nullptr;
92 count_ = other.count_;
93 other.count_ = 0;
94 return *this;
95 }
96
97 bool empty() const { return !head_; }
98 size_t count() const { return count_; }
99
100 TenuredChunk* head() {
101 MOZ_ASSERT(head_)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(head_)>::isValid, "invalid assertion condition");
if ((__builtin_expect(!!(!(!!(head_))), 0))) { do { } while (
false); MOZ_ReportAssertionFailure("head_", "/var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h"
, 101); AnnotateMozCrashReason("MOZ_ASSERT" "(" "head_" ")");
do { *((volatile int*)__null) = 101; __attribute__((nomerge)
) ::abort(); } while (false); } } while (false);
102 return head_;
103 }
104 TenuredChunk* pop();
105 void push(TenuredChunk* chunk);
106 TenuredChunk* remove(TenuredChunk* chunk);
107
108 void sort();
109
110 private:
111 TenuredChunk* mergeSort(TenuredChunk* list, size_t count);
112 bool isSorted() const;
113
114#ifdef DEBUG1
115 public:
116 bool contains(TenuredChunk* chunk) const;
117 bool verify() const;
118 void verifyChunks() const;
119#endif
120
121 public:
122 // Pool mutation does not invalidate an Iter unless the mutation
123 // is of the TenuredChunk currently being visited by the Iter.
124 class Iter {
125 public:
126 explicit Iter(ChunkPool& pool) : current_(pool.head_) {}
127 bool done() const { return !current_; }
128 void next();
129 TenuredChunk* get() const { return current_; }
130 operator TenuredChunk*() const { return get(); }
131 TenuredChunk* operator->() const { return get(); }
132
133 private:
134 TenuredChunk* current_;
135 };
136};
137
138class BackgroundMarkTask : public GCParallelTask {
139 public:
140 explicit BackgroundMarkTask(GCRuntime* gc);
141 void setBudget(const JS::SliceBudget& budget) { this->budget = budget; }
142 void run(AutoLockHelperThreadState& lock) override;
143
144 private:
145 JS::SliceBudget budget;
146};
147
148class BackgroundUnmarkTask : public GCParallelTask {
149 public:
150 explicit BackgroundUnmarkTask(GCRuntime* gc);
151 void initZones();
152 void run(AutoLockHelperThreadState& lock) override;
153
154 ZoneVector zones;
155};
156
157class BackgroundSweepTask : public GCParallelTask {
158 public:
159 explicit BackgroundSweepTask(GCRuntime* gc);
160 void run(AutoLockHelperThreadState& lock) override;
161};
162
163class BackgroundFreeTask : public GCParallelTask {
164 public:
165 explicit BackgroundFreeTask(GCRuntime* gc);
166 void run(AutoLockHelperThreadState& lock) override;
167};
168
169// Performs extra allocation off thread so that when memory is required on the
170// main thread it will already be available and waiting.
171class BackgroundAllocTask : public GCParallelTask {
172 // Guarded by the GC lock.
173 GCLockData<ChunkPool&> chunkPool_;
174
175 const bool enabled_;
176
177 public:
178 BackgroundAllocTask(GCRuntime* gc, ChunkPool& pool);
179 bool enabled() const { return enabled_; }
180
181 void run(AutoLockHelperThreadState& lock) override;
182};
183
184// Search the provided chunks for free arenas and decommit them.
185class BackgroundDecommitTask : public GCParallelTask {
186 public:
187 explicit BackgroundDecommitTask(GCRuntime* gc);
188 void run(AutoLockHelperThreadState& lock) override;
189};
190
191template <typename F>
192struct Callback {
193 F op;
194 void* data;
195
196 Callback() : op(nullptr), data(nullptr) {}
197 Callback(F op, void* data) : op(op), data(data) {}
198};
199
200template <typename F>
201using CallbackVector = Vector<Callback<F>, 4, SystemAllocPolicy>;
202
203using RootedValueMap =
204 HashMap<Value*, const char*, DefaultHasher<Value*>, SystemAllocPolicy>;
205
206using AllocKinds = mozilla::EnumSet<AllocKind, uint64_t>;
207
208// A singly linked list of zones.
209class ZoneList {
210 static Zone* const End;
211
212 Zone* head;
213 Zone* tail;
214
215 public:
216 ZoneList();
217 ~ZoneList();
218
219 bool isEmpty() const;
220 Zone* front() const;
221
222 void prepend(Zone* zone);
223 void append(Zone* zone);
224 void prependList(ZoneList&& other);
225 void appendList(ZoneList&& other);
226 Zone* removeFront();
227 void clear();
228
229 private:
230 explicit ZoneList(Zone* singleZone);
231 void check() const;
232
233 ZoneList(const ZoneList& other) = delete;
234 ZoneList& operator=(const ZoneList& other) = delete;
235};
236
237struct WeakCacheToSweep {
238 JS::detail::WeakCacheBase* cache;
239 JS::Zone* zone;
240};
241
242class WeakCacheSweepIterator {
243 using WeakCacheBase = JS::detail::WeakCacheBase;
244
245 JS::Zone* sweepZone;
246 WeakCacheBase* sweepCache;
247
248 public:
249 explicit WeakCacheSweepIterator(JS::Zone* sweepGroup);
250
251 bool done() const;
252 WeakCacheToSweep get() const;
253 void next();
254
255 private:
256 void settle();
257};
258
259struct SweepingTracer final : public GenericTracerImpl<SweepingTracer> {
260 explicit SweepingTracer(JSRuntime* rt);
261
262 private:
263 template <typename T>
264 void onEdge(T** thingp, const char* name);
265 friend class GenericTracerImpl<SweepingTracer>;
266};
267
268class GCRuntime {
Excessive padding in 'class js::gc::GCRuntime' (82 padding bytes, where 2 is optimal). Optimal fields order: rt, numActiveZoneIters, queuePos, lastLastDitchTime, systemZone, sharedAtomsZone_, delayedMarkingList, markLaterArenas, helperThreadRatio, maxHelperThreads, helperThreadCount, maxMarkingThreads, markingThreadCount, maxParallelThreads, dispatchedParallelTasks, createBudgetCallback, nextCellUniqueId_, verifyPreData, lastGCStartTime_, lastGCEndTime_, initialized, minorGCNumber, majorGCNumber, number, sliceNumber, reservedMarkingThreads, sweepGroups, currentSweepGroup, sweepActions, sweepZone, foregroundFinalizedZone, zonesCompacted, relocatedArenasToRelease, markingValidator, defaultTimeBudgetMS_, maybeMarkStackLimit, inPageLoadCount, lastAllocRateUpdateTime, collectorTimeSinceAllocRateUpdate, permanentAtoms, permanentWellKnownSymbols, emptyChunks_, availableChunks_, fullChunks_, backgroundSweepZones, zonesToMaybeCompact, gcCallback, gcDoCycleCollectionCallback, tenuredCallback, hostCleanupFinalizationRegistryCallback, grayRootTracer, stringStats, heapSize, queuedParallelTasks, weakCachesToSweep, markers, sweepingTracer, rootsHash, buffersToFreeAfterMinorGC, cellsToAssertNotGray, atomMarking, testMarkQueue, mainThreadContext, zones_, selectedForMarking, lock, storeBufferLock, delayedMarkingLock, maybeAtomsToSweep, sweepTask, freeTask, decommitTask, lifoBlocksToFree, lifoBlocksToFreeAfterFullMinorGC, lifoBlocksToFreeAfterNextMinorGC, finalizeCallbacks, updateWeakPointerZonesCallbacks, updateWeakPointerCompartmentCallbacks, nurseryCollectionCallbacks, blackRootTracers, allocTask, markTask, unmarkTask, tunables, storeBuffer_, foregroundFinalizedArenas, nursery_, stats_, schedulingState, numArenasFreeCommitted, majorGCTriggerReason, heapState_, minEmptyChunkCount_, maxEmptyChunkCount_, initialReason, incrementalState, initialState, sweepGroupIndex, sweepMarkResult, zealModeBits, zealFrequency, nextScheduled, zealSliceBudget, gcCallbackDepth, maybeGcOptions, delayedMarkingWorkAdded, fullGCRequested, incrementalGCEnabled, perZoneGCEnabled, cleanUpEverything, grayBitsValid, isIncremental, isFull, isCompacting, useParallelMarking, useZeal, lastMarkSlice, safeToYield, markOnBackgroundThreadDuringSweeping, useBackgroundThreads, haveDiscardedJITCodeThisSlice, hadShutdownGC, requestSliceAfterBackgroundTask, sweepAllocKind, abortSweepAfterCurrentGroup, foregroundFinalizedAllocKind, queueMarkColor, startedCompacting, compactingEnabled, nurseryEnabled, parallelMarkingEnabled, rootsRemoved, deterministicOnly, fullCompartmentChecks, alwaysPreserveCode, lowMemoryState, consider reordering the fields or adding explicit padding members
269 public:
270 explicit GCRuntime(JSRuntime* rt);
271 [[nodiscard]] bool init(uint32_t maxbytes);
272 bool wasInitialized() const { return initialized; }
273 void finishRoots();
274 void finish();
275
276 Zone* atomsZone() {
277 Zone* zone = zones()[0];
278 MOZ_ASSERT(JS::shadow::Zone::from(zone)->isAtomsZone())do { static_assert( mozilla::detail::AssertionConditionType<
decltype(JS::shadow::Zone::from(zone)->isAtomsZone())>::
isValid, "invalid assertion condition"); if ((__builtin_expect
(!!(!(!!(JS::shadow::Zone::from(zone)->isAtomsZone()))), 0
))) { do { } while (false); MOZ_ReportAssertionFailure("JS::shadow::Zone::from(zone)->isAtomsZone()"
, "/var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h"
, 278); AnnotateMozCrashReason("MOZ_ASSERT" "(" "JS::shadow::Zone::from(zone)->isAtomsZone()"
")"); do { *((volatile int*)__null) = 278; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false);
279 return zone;
280 }
281 Zone* maybeSharedAtomsZone() { return sharedAtomsZone_; }
282
283 [[nodiscard]] bool freezeSharedAtomsZone();
284 void restoreSharedAtomsZone();
285
286 JS::HeapState heapState() const { return heapState_; }
287
288 bool hasZealMode(ZealMode mode) const;
289 bool hasAnyZealModeOf(mozilla::EnumSet<ZealMode> mode) const;
290 void clearZealMode(ZealMode mode);
291 bool needZealousGC();
292 bool zealModeControlsYieldPoint() const;
293
294 [[nodiscard]] bool addRoot(Value* vp, const char* name);
295 void removeRoot(Value* vp);
296
297 [[nodiscard]] bool setParameter(JSContext* cx, JSGCParamKey key,
298 uint32_t value);
299 void resetParameter(JSContext* cx, JSGCParamKey key);
300 uint32_t getParameter(JSGCParamKey key);
301
302 void setPerformanceHint(PerformanceHint hint);
303 bool isInPageLoad() const { return inPageLoadCount != 0; }
304
305 [[nodiscard]] bool triggerGC(JS::GCReason reason);
306 // Check whether to trigger a zone GC after allocating GC cells.
307 void maybeTriggerGCAfterAlloc(Zone* zone);
308 // Check whether to trigger a zone GC after malloc memory.
309 void maybeTriggerGCAfterMalloc(Zone* zone);
310 bool maybeTriggerGCAfterMalloc(Zone* zone, const HeapSize& heap,
311 const HeapThreshold& threshold,
312 JS::GCReason reason);
313 // The return value indicates if we were able to do the GC.
314 bool triggerZoneGC(Zone* zone, JS::GCReason reason, size_t usedBytes,
315 size_t thresholdBytes);
316
317 void maybeGC();
318
319 // Return whether we want to run a major GC. If eagerOk is true, include eager
320 // triggers (eg EAGER_ALLOC_TRIGGER) in this determination, and schedule all
321 // zones that exceed the eager thresholds.
322 JS::GCReason wantMajorGC(bool eagerOk);
323 bool checkEagerAllocTrigger(const HeapSize& size,
324 const HeapThreshold& threshold);
325
326 // Do a minor GC if requested, followed by a major GC if requested. The return
327 // value indicates whether a major GC was performed.
328 bool gcIfRequested() { return gcIfRequestedImpl(false); }
329
330 // Internal function to do a GC if previously requested. But if not and
331 // eagerOk, do an eager GC for all Zones that have exceeded the eager
332 // thresholds.
333 //
334 // Return whether a major GC was performed or started.
335 bool gcIfRequestedImpl(bool eagerOk);
336
337 void gc(JS::GCOptions options, JS::GCReason reason);
338 void startGC(JS::GCOptions options, JS::GCReason reason,
339 const JS::SliceBudget& budget);
340 void gcSlice(JS::GCReason reason, const JS::SliceBudget& budget);
341 void finishGC(JS::GCReason reason);
342 void abortGC();
343 void startDebugGC(JS::GCOptions options, const JS::SliceBudget& budget);
344 void debugGCSlice(const JS::SliceBudget& budget);
345
346 void runDebugGC();
347 void notifyRootsRemoved();
348
349 enum TraceOrMarkRuntime { TraceRuntime, MarkRuntime };
350 void traceRuntime(JSTracer* trc, AutoTraceSession& session);
351 void traceRuntimeForMinorGC(JSTracer* trc, AutoGCSession& session);
352
353 void purgeRuntimeForMinorGC();
354
355 void shrinkBuffers();
356 void onOutOfMallocMemory();
357 void onOutOfMallocMemory(const AutoLockGC& lock);
358
359 Nursery& nursery() { return nursery_.ref(); }
360 gc::StoreBuffer& storeBuffer() { return storeBuffer_.ref(); }
361
362 void minorGC(JS::GCReason reason,
363 gcstats::PhaseKind phase = gcstats::PhaseKind::MINOR_GC)
364 JS_HAZ_GC_CALL;
365 void evictNursery(JS::GCReason reason = JS::GCReason::EVICT_NURSERY) {
366 minorGC(reason, gcstats::PhaseKind::EVICT_NURSERY);
367 }
368
369 void* addressOfNurseryPosition() {
370 return nursery_.refNoCheck().addressOfPosition();
371 }
372
373 const void* addressOfLastBufferedWholeCell() {
374 return storeBuffer_.refNoCheck().addressOfLastBufferedWholeCell();
375 }
376
377#ifdef JS_GC_ZEAL1
378 const uint32_t* addressOfZealModeBits() { return &zealModeBits.refNoCheck(); }
379 void getZealBits(uint32_t* zealBits, uint32_t* frequency,
380 uint32_t* nextScheduled);
381 void setZeal(uint8_t zeal, uint32_t frequency);
382 void unsetZeal(uint8_t zeal);
383 bool parseAndSetZeal(const char* str);
384 void setNextScheduled(uint32_t count);
385 void verifyPreBarriers();
386 void maybeVerifyPreBarriers(bool always);
387 bool selectForMarking(JSObject* object);
388 void clearSelectedForMarking();
389 void setDeterministic(bool enable);
390 void setMarkStackLimit(size_t limit, AutoLockGC& lock);
391#endif
392
393 uint64_t nextCellUniqueId() {
394 MOZ_ASSERT(nextCellUniqueId_ > 0)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(nextCellUniqueId_ > 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(nextCellUniqueId_ > 0))),
0))) { do { } while (false); MOZ_ReportAssertionFailure("nextCellUniqueId_ > 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h"
, 394); AnnotateMozCrashReason("MOZ_ASSERT" "(" "nextCellUniqueId_ > 0"
")"); do { *((volatile int*)__null) = 394; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false);
395 uint64_t uid = ++nextCellUniqueId_;
396 return uid;
397 }
398
399 void setLowMemoryState(bool newState) { lowMemoryState = newState; }
400 bool systemHasLowMemory() const { return lowMemoryState; }
401
402 public:
403 // Internal public interface
404 ZoneVector& zones() { return zones_.ref(); }
405 gcstats::Statistics& stats() { return stats_.ref(); }
406 const gcstats::Statistics& stats() const { return stats_.ref(); }
407 State state() const { return incrementalState; }
408 bool isHeapCompacting() const { return state() == State::Compact; }
409 bool isForegroundSweeping() const { return state() == State::Sweep; }
410 bool isBackgroundSweeping() const { return sweepTask.wasStarted(); }
411 bool isBackgroundMarking() const { return markTask.wasStarted(); }
412 void waitBackgroundSweepEnd();
413 void waitBackgroundAllocEnd() { allocTask.cancelAndWait(); }
414 void waitBackgroundFreeEnd();
415 void waitForBackgroundTasks();
416 bool isWaitingOnBackgroundTask() const;
417
418 void lockGC() { lock.lock(); }
419 void unlockGC() { lock.unlock(); }
420
421 void lockStoreBuffer() { storeBufferLock.lock(); }
422 void unlockStoreBuffer() { storeBufferLock.unlock(); }
423
424#ifdef DEBUG1
425 void assertCurrentThreadHasLockedGC() const {
426 lock.assertOwnedByCurrentThread();
427 }
428 void assertCurrentThreadHasLockedStoreBuffer() const {
429 storeBufferLock.assertOwnedByCurrentThread();
430 }
431#endif // DEBUG
432
433 void setAlwaysPreserveCode() { alwaysPreserveCode = true; }
434
435 void setIncrementalGCEnabled(bool enabled);
436 void setNurseryEnabled(bool enabled);
437
438 bool isIncrementalGCEnabled() const { return incrementalGCEnabled; }
439 bool isPerZoneGCEnabled() const { return perZoneGCEnabled; }
440 bool isCompactingGCEnabled() const;
441 bool isParallelMarkingEnabled() const { return parallelMarkingEnabled; }
442
443 bool isIncrementalGCInProgress() const {
444 return state() != State::NotActive && !isVerifyPreBarriersEnabled();
445 }
446
447 bool hasForegroundWork() const;
448
449 bool isShrinkingGC() const { return gcOptions() == JS::GCOptions::Shrink; }
450
451 bool isShutdownGC() const { return gcOptions() == JS::GCOptions::Shutdown; }
452
453#ifdef DEBUG1
454 bool isShuttingDown() const { return hadShutdownGC; }
455#endif
456
457 bool initSweepActions();
458
459 void setGrayRootsTracer(JSGrayRootsTracer traceOp, void* data);
460 [[nodiscard]] bool addBlackRootsTracer(JSTraceDataOp traceOp, void* data);
461 void removeBlackRootsTracer(JSTraceDataOp traceOp, void* data);
462 void clearBlackAndGrayRootTracers();
463
464 void setGCCallback(JSGCCallback callback, void* data);
465 void callGCCallback(JSGCStatus status, JS::GCReason reason) const;
466 void setObjectsTenuredCallback(JSObjectsTenuredCallback callback, void* data);
467 void callObjectsTenuredCallback();
468 [[nodiscard]] bool addFinalizeCallback(JSFinalizeCallback callback,
469 void* data);
470 void removeFinalizeCallback(JSFinalizeCallback callback);
471 void setHostCleanupFinalizationRegistryCallback(
472 JSHostCleanupFinalizationRegistryCallback callback, void* data);
473 void callHostCleanupFinalizationRegistryCallback(
474 JSFunction* doCleanup, GlobalObject* incumbentGlobal);
475 [[nodiscard]] bool addWeakPointerZonesCallback(
476 JSWeakPointerZonesCallback callback, void* data);
477 void removeWeakPointerZonesCallback(JSWeakPointerZonesCallback callback);
478 [[nodiscard]] bool addWeakPointerCompartmentCallback(
479 JSWeakPointerCompartmentCallback callback, void* data);
480 void removeWeakPointerCompartmentCallback(
481 JSWeakPointerCompartmentCallback callback);
482 JS::GCSliceCallback setSliceCallback(JS::GCSliceCallback callback);
483 bool addNurseryCollectionCallback(JS::GCNurseryCollectionCallback callback,
484 void* data);
485 void removeNurseryCollectionCallback(JS::GCNurseryCollectionCallback callback,
486 void* data);
487 JS::DoCycleCollectionCallback setDoCycleCollectionCallback(
488 JS::DoCycleCollectionCallback callback);
489 void callNurseryCollectionCallbacks(JS::GCNurseryProgress progress,
490 JS::GCReason reason);
491
492 bool addFinalizationRegistry(JSContext* cx,
493 Handle<FinalizationRegistryObject*> registry);
494 bool registerWithFinalizationRegistry(JSContext* cx, HandleObject target,
495 HandleObject record);
496 void queueFinalizationRegistryForCleanup(FinalizationQueueObject* queue);
497
498 void nukeFinalizationRecordWrapper(JSObject* wrapper,
499 FinalizationRecordObject* record);
500 void nukeWeakRefWrapper(JSObject* wrapper, WeakRefObject* weakRef);
501
502 void setFullCompartmentChecks(bool enable);
503
504 // Get the main marking tracer.
505 GCMarker& marker() { return *markers[0]; }
506
507 JS::Zone* getCurrentSweepGroup() { return currentSweepGroup; }
508 unsigned getCurrentSweepGroupIndex() {
509 MOZ_ASSERT_IF(unsigned(state()) < unsigned(State::Sweep),do { if (unsigned(state()) < unsigned(State::Sweep)) { do {
static_assert( mozilla::detail::AssertionConditionType<decltype
(sweepGroupIndex == 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(sweepGroupIndex == 0))), 0))
) { do { } while (false); MOZ_ReportAssertionFailure("sweepGroupIndex == 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h"
, 510); AnnotateMozCrashReason("MOZ_ASSERT" "(" "sweepGroupIndex == 0"
")"); do { *((volatile int*)__null) = 510; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false); } } while (
false)
510 sweepGroupIndex == 0)do { if (unsigned(state()) < unsigned(State::Sweep)) { do {
static_assert( mozilla::detail::AssertionConditionType<decltype
(sweepGroupIndex == 0)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(sweepGroupIndex == 0))), 0))
) { do { } while (false); MOZ_ReportAssertionFailure("sweepGroupIndex == 0"
, "/var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h"
, 510); AnnotateMozCrashReason("MOZ_ASSERT" "(" "sweepGroupIndex == 0"
")"); do { *((volatile int*)__null) = 510; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false); } } while (
false);
511 return sweepGroupIndex;
512 }
513
514 uint64_t gcNumber() const { return number; }
515 void incGcNumber() { ++number; }
516
517 uint64_t minorGCCount() const { return minorGCNumber; }
518 void incMinorGcNumber() { ++minorGCNumber; }
519
520 uint64_t majorGCCount() const { return majorGCNumber; }
521 void incMajorGcNumber() { ++majorGCNumber; }
522
523 uint64_t gcSliceCount() const { return sliceNumber; }
524 void incGcSliceNumber() { ++sliceNumber; }
525
526 int64_t defaultSliceBudgetMS() const { return defaultTimeBudgetMS_; }
527
528 bool isIncrementalGc() const { return isIncremental; }
529 bool isFullGc() const { return isFull; }
530 bool isCompactingGc() const { return isCompacting; }
531 bool didCompactZones() const { return isCompacting && zonesCompacted; }
532
533 bool areGrayBitsValid() const { return grayBitsValid; }
534 void setGrayBitsInvalid() { grayBitsValid = false; }
535
536 mozilla::TimeStamp lastGCStartTime() const { return lastGCStartTime_; }
537 mozilla::TimeStamp lastGCEndTime() const { return lastGCEndTime_; }
538
539 bool majorGCRequested() const {
540 return majorGCTriggerReason != JS::GCReason::NO_REASON;
541 }
542
543 double computeHeapGrowthFactor(size_t lastBytes);
544 size_t computeTriggerBytes(double growthFactor, size_t lastBytes);
545
546 inline void updateOnFreeArenaAlloc(const TenuredChunkInfo& info);
547 void updateOnArenaFree() { ++numArenasFreeCommitted; }
548
549 ChunkPool& fullChunks(const AutoLockGC& lock) { return fullChunks_.ref(); }
550 ChunkPool& availableChunks(const AutoLockGC& lock) {
551 return availableChunks_.ref();
552 }
553 ChunkPool& emptyChunks(const AutoLockGC& lock) { return emptyChunks_.ref(); }
554 const ChunkPool& fullChunks(const AutoLockGC& lock) const {
555 return fullChunks_.ref();
556 }
557 const ChunkPool& availableChunks(const AutoLockGC& lock) const {
558 return availableChunks_.ref();
559 }
560 const ChunkPool& emptyChunks(const AutoLockGC& lock) const {
561 return emptyChunks_.ref();
562 }
563 using NonEmptyChunksIter = ChainedIterator<ChunkPool::Iter, 2>;
564 NonEmptyChunksIter allNonEmptyChunks(const AutoLockGC& lock) {
565 return NonEmptyChunksIter(availableChunks(lock), fullChunks(lock));
566 }
567 uint32_t minEmptyChunkCount(const AutoLockGC& lock) const {
568 return minEmptyChunkCount_;
569 }
570 uint32_t maxEmptyChunkCount(const AutoLockGC& lock) const {
571 return maxEmptyChunkCount_;
572 }
573#ifdef DEBUG1
574 void verifyAllChunks();
575#endif
576
577 TenuredChunk* getOrAllocChunk(AutoLockGCBgAlloc& lock);
578 void recycleChunk(TenuredChunk* chunk, const AutoLockGC& lock);
579
580#ifdef JS_GC_ZEAL1
581 void startVerifyPreBarriers();
582 void endVerifyPreBarriers();
583 void finishVerifier();
584 bool isVerifyPreBarriersEnabled() const { return verifyPreData.refNoCheck(); }
585 bool shouldYieldForZeal(ZealMode mode);
586#else
587 bool isVerifyPreBarriersEnabled() const { return false; }
588#endif
589
590#ifdef JSGC_HASH_TABLE_CHECKS
591 void checkHashTablesAfterMovingGC();
592#endif
593
594 // Crawl the heap to check whether an arbitary pointer is within a cell of
595 // the given kind. (TraceKind::Null means to ignore the kind.)
596 bool isPointerWithinTenuredCell(
597 void* ptr, JS::TraceKind traceKind = JS::TraceKind::Null);
598
599#ifdef DEBUG1
600 bool hasZone(Zone* target);
601#endif
602
603 // Queue memory memory to be freed on a background thread if possible.
604 void queueUnusedLifoBlocksForFree(LifoAlloc* lifo);
605 void queueAllLifoBlocksForFreeAfterMinorGC(LifoAlloc* lifo);
606 void queueBuffersForFreeAfterMinorGC(Nursery::BufferSet& buffers);
607
608 // Public here for ReleaseArenaLists and FinalizeTypedArenas.
609 void releaseArena(Arena* arena, const AutoLockGC& lock);
610
611 // Allocator internals.
612 static void* refillFreeListInGC(Zone* zone, AllocKind thingKind);
613
614 // Delayed marking.
615 void delayMarkingChildren(gc::Cell* cell, MarkColor color);
616 bool hasDelayedMarking() const;
617 void markAllDelayedChildren(ShouldReportMarkTime reportTime);
618
619 // If we have yielded to the mutator while foreground finalizing arenas from
620 // zone |zone| with kind |kind| then return a list of the arenas finalized so
621 // far. These will have been removed from the main arena lists at this
622 // point. Otherwise return nullptr.
623 SortedArenaList* maybeGetForegroundFinalizedArenas(Zone* zone,
624 AllocKind kind);
625
626 /*
627 * Concurrent sweep infrastructure.
628 */
629 void startTask(GCParallelTask& task, AutoLockHelperThreadState& lock);
630 void joinTask(GCParallelTask& task, AutoLockHelperThreadState& lock);
631 void updateHelperThreadCount();
632 size_t parallelWorkerCount() const;
633
634 // GC parallel task dispatch infrastructure.
635 size_t getMaxParallelThreads() const;
636 void dispatchOrQueueParallelTask(GCParallelTask* task,
637 const AutoLockHelperThreadState& lock);
638 void maybeDispatchParallelTasks(const AutoLockHelperThreadState& lock);
639 void onParallelTaskEnd(bool wasDispatched,
640 const AutoLockHelperThreadState& lock);
641
642 // Parallel marking.
643 bool setParallelMarkingEnabled(bool enabled);
644 bool initOrDisableParallelMarking();
645 [[nodiscard]] bool updateMarkersVector();
646 size_t markingWorkerCount() const;
647
648 // WeakRefs
649 bool registerWeakRef(HandleObject target, HandleObject weakRef);
650 void traceKeptObjects(JSTracer* trc);
651
652 JS::GCReason lastStartReason() const { return initialReason; }
653
654 void updateAllocationRates();
655
656 // Allocator internals
657 static void* refillFreeList(JSContext* cx, AllocKind thingKind);
658 void attemptLastDitchGC(JSContext* cx);
659
660 // Test mark queue.
661#ifdef DEBUG1
662 const GCVector<HeapPtr<JS::Value>, 0, SystemAllocPolicy>& getTestMarkQueue()
663 const;
664 [[nodiscard]] bool appendTestMarkQueue(const JS::Value& value);
665 void clearTestMarkQueue();
666 size_t testMarkQueuePos() const;
667#endif
668
669 private:
670 enum IncrementalResult { ResetIncremental = 0, Ok };
671
672 [[nodiscard]] bool setParameter(JSGCParamKey key, uint32_t value,
673 AutoLockGC& lock);
674 void resetParameter(JSGCParamKey key, AutoLockGC& lock);
675 uint32_t getParameter(JSGCParamKey key, const AutoLockGC& lock);
676 bool setThreadParameter(JSGCParamKey key, uint32_t value, AutoLockGC& lock);
677 void resetThreadParameter(JSGCParamKey key, AutoLockGC& lock);
678 void updateThreadDataStructures(AutoLockGC& lock);
679
680 JS::GCOptions gcOptions() const { return maybeGcOptions.ref().ref(); }
681
682 TriggerResult checkHeapThreshold(Zone* zone, const HeapSize& heapSize,
683 const HeapThreshold& heapThreshold);
684
685 void updateSchedulingStateOnGCStart();
686 void updateSchedulingStateAfterCollection(mozilla::TimeStamp currentTime);
687 void updateAllGCStartThresholds();
688
689 // For ArenaLists::allocateFromArena()
690 friend class ArenaLists;
691 TenuredChunk* pickChunk(AutoLockGCBgAlloc& lock);
692 Arena* allocateArena(TenuredChunk* chunk, Zone* zone, AllocKind kind,
693 ShouldCheckThresholds checkThresholds,
694 const AutoLockGC& lock);
695
696 /*
697 * Return the list of chunks that can be released outside the GC lock.
698 * Must be called either during the GC or with the GC lock taken.
699 */
700 friend class BackgroundDecommitTask;
701 bool tooManyEmptyChunks(const AutoLockGC& lock);
702 ChunkPool expireEmptyChunkPool(const AutoLockGC& lock);
703 void freeEmptyChunks(const AutoLockGC& lock);
704 void prepareToFreeChunk(TenuredChunkInfo& info);
705 void setMinEmptyChunkCount(uint32_t value, const AutoLockGC& lock);
706 void setMaxEmptyChunkCount(uint32_t value, const AutoLockGC& lock);
707
708 friend class BackgroundAllocTask;
709 bool wantBackgroundAllocation(const AutoLockGC& lock) const;
710 void startBackgroundAllocTaskIfIdle();
711
712 void requestMajorGC(JS::GCReason reason);
713 JS::SliceBudget defaultBudget(JS::GCReason reason, int64_t millis);
714 bool maybeIncreaseSliceBudget(JS::SliceBudget& budget);
715 bool maybeIncreaseSliceBudgetForLongCollections(JS::SliceBudget& budget);
716 bool maybeIncreaseSliceBudgetForUrgentCollections(JS::SliceBudget& budget);
717 IncrementalResult budgetIncrementalGC(bool nonincrementalByAPI,
718 JS::GCReason reason,
719 JS::SliceBudget& budget);
720 void checkZoneIsScheduled(Zone* zone, JS::GCReason reason,
721 const char* trigger);
722 IncrementalResult resetIncrementalGC(GCAbortReason reason);
723
724 // Assert if the system state is such that we should never
725 // receive a request to do GC work.
726 void checkCanCallAPI();
727
728 // Check if the system state is such that GC has been supressed
729 // or otherwise delayed.
730 [[nodiscard]] bool checkIfGCAllowedInCurrentState(JS::GCReason reason);
731
732 gcstats::ZoneGCStats scanZonesBeforeGC();
733
734 void setGCOptions(JS::GCOptions options);
735
736 void collect(bool nonincrementalByAPI, const JS::SliceBudget& budget,
737 JS::GCReason reason) JS_HAZ_GC_CALL;
738
739 /*
740 * Run one GC "cycle" (either a slice of incremental GC or an entire
741 * non-incremental GC).
742 *
743 * Returns:
744 * * ResetIncremental if we "reset" an existing incremental GC, which would
745 * force us to run another cycle or
746 * * Ok otherwise.
747 */
748 [[nodiscard]] IncrementalResult gcCycle(bool nonincrementalByAPI,
749 const JS::SliceBudget& budgetArg,
750 JS::GCReason reason);
751 bool shouldRepeatForDeadZone(JS::GCReason reason);
752
753 void incrementalSlice(JS::SliceBudget& budget, JS::GCReason reason,
754 bool budgetWasIncreased);
755
756 bool mightSweepInThisSlice(bool nonIncremental);
757 void collectNurseryFromMajorGC(JS::GCReason reason);
758 void collectNursery(JS::GCOptions options, JS::GCReason reason,
759 gcstats::PhaseKind phase);
760
761 friend class AutoCallGCCallbacks;
762 void maybeCallGCCallback(JSGCStatus status, JS::GCReason reason);
763
764 void startCollection(JS::GCReason reason);
765
766 void purgeRuntime();
767 [[nodiscard]] bool beginPreparePhase(JS::GCReason reason,
768 AutoGCSession& session);
769 bool prepareZonesForCollection(JS::GCReason reason, bool* isFullOut);
770 void unmarkWeakMaps();
771 void endPreparePhase(JS::GCReason reason);
772 void beginMarkPhase(AutoGCSession& session);
773 bool shouldPreserveJITCode(JS::Realm* realm,
774 const mozilla::TimeStamp& currentTime,
775 JS::GCReason reason, bool canAllocateMoreCode,
776 bool isActiveCompartment);
777 void discardJITCodeForGC();
778 void startBackgroundFreeAfterMinorGC();
779 void relazifyFunctionsForShrinkingGC();
780 void purgePropMapTablesForShrinkingGC();
781 void purgeSourceURLsForShrinkingGC();
782 void traceRuntimeForMajorGC(JSTracer* trc, AutoGCSession& session);
783 void traceRuntimeAtoms(JSTracer* trc);
784 void traceRuntimeCommon(JSTracer* trc, TraceOrMarkRuntime traceOrMark);
785 void traceEmbeddingBlackRoots(JSTracer* trc);
786 void traceEmbeddingGrayRoots(JSTracer* trc);
787 IncrementalProgress traceEmbeddingGrayRoots(JSTracer* trc,
788 JS::SliceBudget& budget);
789 void checkNoRuntimeRoots(AutoGCSession& session);
790 void maybeDoCycleCollection();
791 void findDeadCompartments();
792
793 friend class BackgroundMarkTask;
794 enum ParallelMarking : bool {
795 SingleThreadedMarking = false,
796 AllowParallelMarking = true
797 };
798 IncrementalProgress markUntilBudgetExhausted(
799 JS::SliceBudget& sliceBudget,
800 ParallelMarking allowParallelMarking = SingleThreadedMarking,
801 ShouldReportMarkTime reportTime = ReportMarkTime);
802 bool canMarkInParallel() const;
803 bool initParallelMarking();
804 void finishParallelMarkers();
805
806 bool reserveMarkingThreads(size_t count);
807 void releaseMarkingThreads();
808
809 bool hasMarkingWork(MarkColor color) const;
810
811 void drainMarkStack();
812
813#ifdef DEBUG1
814 void assertNoMarkingWork() const;
815#else
816 void assertNoMarkingWork() const {}
817#endif
818
819 void markDelayedChildren(gc::Arena* arena, MarkColor color);
820 void processDelayedMarkingList(gc::MarkColor color);
821 void rebuildDelayedMarkingList();
822 void appendToDelayedMarkingList(gc::Arena** listTail, gc::Arena* arena);
823 void resetDelayedMarking();
824 template <typename F>
825 void forEachDelayedMarkingArena(F&& f);
826
827 template <class ZoneIterT>
828 IncrementalProgress markWeakReferences(JS::SliceBudget& budget);
829 IncrementalProgress markWeakReferencesInCurrentGroup(JS::SliceBudget& budget);
830 IncrementalProgress markGrayRoots(JS::SliceBudget& budget,
831 gcstats::PhaseKind phase);
832 void markBufferedGrayRoots(JS::Zone* zone);
833 IncrementalProgress markAllWeakReferences();
834 void markAllGrayReferences(gcstats::PhaseKind phase);
835
836 // The mark queue is a testing-only feature for controlling mark ordering and
837 // yield timing.
838 enum MarkQueueProgress {
839 QueueYielded, // End this incremental GC slice, if possible
840 QueueComplete, // Done with the queue
841 QueueSuspended // Continue the GC without ending the slice
842 };
843 MarkQueueProgress processTestMarkQueue();
844
845 // GC Sweeping. Implemented in Sweeping.cpp.
846 void beginSweepPhase(JS::GCReason reason, AutoGCSession& session);
847 void dropStringWrappers();
848 void groupZonesForSweeping(JS::GCReason reason);
849 [[nodiscard]] bool findSweepGroupEdges();
850 [[nodiscard]] bool addEdgesForMarkQueue();
851 void moveToNextSweepGroup();
852 void resetGrayList(Compartment* comp);
853 IncrementalProgress beginMarkingSweepGroup(JS::GCContext* gcx,
854 JS::SliceBudget& budget);
855 IncrementalProgress markGrayRootsInCurrentGroup(JS::GCContext* gcx,
856 JS::SliceBudget& budget);
857 IncrementalProgress markGray(JS::GCContext* gcx, JS::SliceBudget& budget);
858 IncrementalProgress endMarkingSweepGroup(JS::GCContext* gcx,
859 JS::SliceBudget& budget);
860 void markIncomingGrayCrossCompartmentPointers();
861 IncrementalProgress beginSweepingSweepGroup(JS::GCContext* gcx,
862 JS::SliceBudget& budget);
863 void initBackgroundSweep(Zone* zone, JS::GCContext* gcx,
864 const FinalizePhase& phase);
865 IncrementalProgress markDuringSweeping(JS::GCContext* gcx,
866 JS::SliceBudget& budget);
867 void updateAtomsBitmap();
868 void sweepCCWrappers();
869 void sweepRealmGlobals();
870 void sweepEmbeddingWeakPointers(JS::GCContext* gcx);
871 void sweepMisc();
872 void sweepCompressionTasks();
873 void sweepWeakMaps();
874 void sweepUniqueIds();
875 void sweepObjectsWithWeakPointers();
876 void sweepDebuggerOnMainThread(JS::GCContext* gcx);
877 void sweepJitDataOnMainThread(JS::GCContext* gcx);
878 void sweepFinalizationObserversOnMainThread();
879 void traceWeakFinalizationObserverEdges(JSTracer* trc, Zone* zone);
880 void sweepWeakRefs();
881 IncrementalProgress endSweepingSweepGroup(JS::GCContext* gcx,
882 JS::SliceBudget& budget);
883 IncrementalProgress performSweepActions(JS::SliceBudget& sliceBudget);
884 void startSweepingAtomsTable();
885 IncrementalProgress sweepAtomsTable(JS::GCContext* gcx,
886 JS::SliceBudget& budget);
887 IncrementalProgress sweepWeakCaches(JS::GCContext* gcx,
888 JS::SliceBudget& budget);
889 IncrementalProgress finalizeAllocKind(JS::GCContext* gcx,
890 JS::SliceBudget& budget);
891 bool foregroundFinalize(JS::GCContext* gcx, Zone* zone, AllocKind thingKind,
892 JS::SliceBudget& sliceBudget,
893 SortedArenaList& sweepList);
894 IncrementalProgress sweepPropMapTree(JS::GCContext* gcx,
895 JS::SliceBudget& budget);
896 void endSweepPhase(bool destroyingRuntime);
897 void queueZonesAndStartBackgroundSweep(ZoneList&& zones);
898 void sweepFromBackgroundThread(AutoLockHelperThreadState& lock);
899 void startBackgroundFree();
900 void freeFromBackgroundThread(AutoLockHelperThreadState& lock);
901 void sweepBackgroundThings(ZoneList& zones);
902 void backgroundFinalize(JS::GCContext* gcx, Zone* zone, AllocKind kind,
903 Arena** empty);
904 void prepareForSweepSlice(JS::GCReason reason);
905 void assertBackgroundSweepingFinished();
906#ifdef DEBUG1
907 bool zoneInCurrentSweepGroup(Zone* zone) const;
908#endif
909
910 bool allCCVisibleZonesWereCollected();
911 void sweepZones(JS::GCContext* gcx, bool destroyingRuntime);
912 bool shouldDecommit() const;
913 void startDecommit();
914 void decommitEmptyChunks(const bool& cancel, AutoLockGC& lock);
915 void decommitFreeArenas(const bool& cancel, AutoLockGC& lock);
916 void decommitFreeArenasWithoutUnlocking(const AutoLockGC& lock);
917
918 // Compacting GC. Implemented in Compacting.cpp.
919 bool shouldCompact();
920 void beginCompactPhase();
921 IncrementalProgress compactPhase(JS::GCReason reason,
922 JS::SliceBudget& sliceBudget,
923 AutoGCSession& session);
924 void endCompactPhase();
925 void sweepZoneAfterCompacting(MovingTracer* trc, Zone* zone);
926 bool canRelocateZone(Zone* zone) const;
927 [[nodiscard]] bool relocateArenas(Zone* zone, JS::GCReason reason,
928 Arena*& relocatedListOut,
929 JS::SliceBudget& sliceBudget);
930 void updateCellPointers(Zone* zone, AllocKinds kinds);
931 void updateAllCellPointers(MovingTracer* trc, Zone* zone);
932 void updateZonePointersToRelocatedCells(Zone* zone);
933 void updateRuntimePointersToRelocatedCells(AutoGCSession& session);
934 void clearRelocatedArenas(Arena* arenaList, JS::GCReason reason);
935 void clearRelocatedArenasWithoutUnlocking(Arena* arenaList,
936 JS::GCReason reason,
937 const AutoLockGC& lock);
938 void releaseRelocatedArenas(Arena* arenaList);
939 void releaseRelocatedArenasWithoutUnlocking(Arena* arenaList,
940 const AutoLockGC& lock);
941#ifdef DEBUG1
942 void protectOrReleaseRelocatedArenas(Arena* arenaList, JS::GCReason reason);
943 void protectAndHoldArenas(Arena* arenaList);
944 void unprotectHeldRelocatedArenas(const AutoLockGC& lock);
945 void releaseHeldRelocatedArenas();
946 void releaseHeldRelocatedArenasWithoutUnlocking(const AutoLockGC& lock);
947#endif
948
949 /*
950 * Whether to immediately trigger a slice after a background task
951 * finishes. This may not happen at a convenient time, so the consideration is
952 * whether the slice will run quickly or may take a long time.
953 */
954 enum ShouldTriggerSliceWhenFinished : bool {
955 DontTriggerSliceWhenFinished = false,
956 TriggerSliceWhenFinished = true
957 };
958
959 IncrementalProgress waitForBackgroundTask(
960 GCParallelTask& task, const JS::SliceBudget& budget,
961 bool shouldPauseMutator, ShouldTriggerSliceWhenFinished triggerSlice);
962
963 void maybeRequestGCAfterBackgroundTask(const AutoLockHelperThreadState& lock);
964 void cancelRequestedGCAfterBackgroundTask();
965 void finishCollection(JS::GCReason reason);
966 void maybeStopPretenuring();
967 void checkGCStateNotInUse();
968 IncrementalProgress joinBackgroundMarkTask();
969
970#ifdef JS_GC_ZEAL1
971 void computeNonIncrementalMarkingForValidation(AutoGCSession& session);
972 void validateIncrementalMarking();
973 void finishMarkingValidation();
974#endif
975
976#ifdef DEBUG1
977 void checkForCompartmentMismatches();
978#endif
979
980 void callFinalizeCallbacks(JS::GCContext* gcx, JSFinalizeStatus status) const;
981 void callWeakPointerZonesCallbacks(JSTracer* trc) const;
982 void callWeakPointerCompartmentCallbacks(JSTracer* trc,
983 JS::Compartment* comp) const;
984 void callDoCycleCollectionCallback(JSContext* cx);
985
986 public:
987 JSRuntime* const rt;
988
989 // Embedders can use this zone however they wish.
990 MainThreadData<JS::Zone*> systemZone;
991
992 MainThreadData<JS::GCContext> mainThreadContext;
993
994 private:
995 // For parent runtimes, a zone containing atoms that is shared by child
996 // runtimes.
997 MainThreadData<Zone*> sharedAtomsZone_;
998
999 // All zones in the runtime. The first element is always the atoms zone.
1000 MainThreadOrGCTaskData<ZoneVector> zones_;
1001
1002 // Any activity affecting the heap.
1003 MainThreadOrGCTaskData<JS::HeapState> heapState_;
1004 friend class AutoHeapSession;
1005 friend class JS::AutoEnterCycleCollection;
1006
1007 UnprotectedData<gcstats::Statistics> stats_;
1008
1009 public:
1010 js::StringStats stringStats;
1011
1012 Vector<UniquePtr<GCMarker>, 1, SystemAllocPolicy> markers;
1013
1014 // Delayed marking support in case we OOM pushing work onto the mark stack.
1015 MainThreadOrGCTaskData<js::gc::Arena*> delayedMarkingList;
1016 MainThreadOrGCTaskData<bool> delayedMarkingWorkAdded;
1017#ifdef DEBUG1
1018 /* Count of arenas that are currently in the stack. */
1019 MainThreadOrGCTaskData<size_t> markLaterArenas;
1020#endif
1021
1022 SweepingTracer sweepingTracer;
1023
1024 /* Track total GC heap size for this runtime. */
1025 HeapSize heapSize;
1026
1027 /* GC scheduling state and parameters. */
1028 GCSchedulingTunables tunables;
1029 GCSchedulingState schedulingState;
1030 MainThreadData<bool> fullGCRequested;
1031
1032 // Helper thread configuration.
1033 MainThreadData<double> helperThreadRatio;
1034 MainThreadData<size_t> maxHelperThreads;
1035 MainThreadOrGCTaskData<size_t> helperThreadCount;
1036 MainThreadData<size_t> maxMarkingThreads;
1037 MainThreadData<size_t> markingThreadCount;
1038
1039 // Per-runtime helper thread task queue. Can be accessed from helper threads
1040 // in maybeDispatchParallelTasks().
1041 HelperThreadLockData<size_t> maxParallelThreads;
1042 HelperThreadLockData<size_t> dispatchedParallelTasks;
1043 HelperThreadLockData<GCParallelTaskList> queuedParallelTasks;
1044
1045 // State used for managing atom mark bitmaps in each zone.
1046 AtomMarkingRuntime atomMarking;
1047
1048 /*
1049 * Pointer to a callback that, if set, will be used to create a
1050 * budget for internally-triggered GCs.
1051 */
1052 MainThreadData<JS::CreateSliceBudgetCallback> createBudgetCallback;
1053
1054 private:
1055 // Arenas used for permanent things created at startup and shared by child
1056 // runtimes.
1057 MainThreadData<ArenaList> permanentAtoms;
1058 MainThreadData<ArenaList> permanentWellKnownSymbols;
1059
1060 // When chunks are empty, they reside in the emptyChunks pool and are
1061 // re-used as needed or eventually expired if not re-used. The emptyChunks
1062 // pool gets refilled from the background allocation task heuristically so
1063 // that empty chunks should always be available for immediate allocation
1064 // without syscalls.
1065 GCLockData<ChunkPool> emptyChunks_;
1066
1067 // Chunks which have had some, but not all, of their arenas allocated live
1068 // in the available chunk lists. When all available arenas in a chunk have
1069 // been allocated, the chunk is removed from the available list and moved
1070 // to the fullChunks pool. During a GC, if all arenas are free, the chunk
1071 // is moved back to the emptyChunks pool and scheduled for eventual
1072 // release.
1073 GCLockData<ChunkPool> availableChunks_;
1074
1075 // When all arenas in a chunk are used, it is moved to the fullChunks pool
1076 // so as to reduce the cost of operations on the available lists.
1077 GCLockData<ChunkPool> fullChunks_;
1078
1079 /*
1080 * JSGC_MIN_EMPTY_CHUNK_COUNT
1081 * JSGC_MAX_EMPTY_CHUNK_COUNT
1082 *
1083 * Controls the number of empty chunks reserved for future allocation.
1084 *
1085 * They can be read off main thread by the background allocation task and the
1086 * background decommit task.
1087 */
1088 GCLockData<uint32_t> minEmptyChunkCount_;
1089 GCLockData<uint32_t> maxEmptyChunkCount_;
1090
1091 MainThreadData<RootedValueMap> rootsHash;
1092
1093 // An incrementing id used to assign unique ids to cells that require one.
1094 MainThreadData<uint64_t> nextCellUniqueId_;
1095
1096 /*
1097 * Number of the committed arenas in all GC chunks including empty chunks.
1098 */
1099 mozilla::Atomic<uint32_t, mozilla::ReleaseAcquire> numArenasFreeCommitted;
1100 MainThreadData<VerifyPreTracer*> verifyPreData;
1101
1102 MainThreadData<mozilla::TimeStamp> lastGCStartTime_;
1103 MainThreadData<mozilla::TimeStamp> lastGCEndTime_;
1104
1105 WriteOnceData<bool> initialized;
1106 MainThreadData<bool> incrementalGCEnabled;
1107 MainThreadData<bool> perZoneGCEnabled;
1108
1109 mozilla::Atomic<size_t, mozilla::ReleaseAcquire> numActiveZoneIters;
1110
1111 /* During shutdown, the GC needs to clean up every possible object. */
1112 MainThreadData<bool> cleanUpEverything;
1113
1114 /*
1115 * The gray bits can become invalid if UnmarkGray overflows the stack. A
1116 * full GC will reset this bit, since it fills in all the gray bits.
1117 */
1118 UnprotectedData<bool> grayBitsValid;
1119
1120 mozilla::Atomic<JS::GCReason, mozilla::ReleaseAcquire> majorGCTriggerReason;
1121
1122 /* Incremented at the start of every minor GC. */
1123 MainThreadData<uint64_t> minorGCNumber;
1124
1125 /* Incremented at the start of every major GC. */
1126 MainThreadData<uint64_t> majorGCNumber;
1127
1128 /* Incremented on every GC slice or minor collection. */
1129 MainThreadData<uint64_t> number;
1130
1131 /* Incremented on every GC slice. */
1132 MainThreadData<uint64_t> sliceNumber;
1133
1134 /*
1135 * This runtime's current contribution to the global number of helper threads
1136 * 'reserved' for parallel marking. Does not affect other uses of helper
1137 * threads.
1138 */
1139 MainThreadData<size_t> reservedMarkingThreads;
1140
1141 /* Whether the currently running GC can finish in multiple slices. */
1142 MainThreadOrGCTaskData<bool> isIncremental;
1143
1144 /* Whether all zones are being collected in first GC slice. */
1145 MainThreadData<bool> isFull;
1146
1147 /* Whether the heap will be compacted at the end of GC. */
1148 MainThreadData<bool> isCompacting;
1149
1150 /* Whether to use parallel marking. */
1151 MainThreadData<ParallelMarking> useParallelMarking;
1152
1153 /* The invocation kind of the current GC, set at the start of collection. */
1154 MainThreadOrGCTaskData<mozilla::Maybe<JS::GCOptions>> maybeGcOptions;
1155
1156 /* The initial GC reason, taken from the first slice. */
1157 MainThreadData<JS::GCReason> initialReason;
1158
1159 /*
1160 * The current incremental GC phase. This is also used internally in
1161 * non-incremental GC.
1162 */
1163 MainThreadOrGCTaskData<State> incrementalState;
1164
1165 /* The incremental state at the start of this slice. */
1166 MainThreadOrGCTaskData<State> initialState;
1167
1168 /* Whether to pay attention the zeal settings in this incremental slice. */
1169#ifdef JS_GC_ZEAL1
1170 MainThreadData<bool> useZeal;
1171#else
1172 const bool useZeal;
1173#endif
1174
1175 /* Indicates that the last incremental slice exhausted the mark stack. */
1176 MainThreadData<bool> lastMarkSlice;
1177
1178 // Whether it's currently safe to yield to the mutator in an incremental GC.
1179 MainThreadData<bool> safeToYield;
1180
1181 // Whether to do any marking caused by barriers on a background thread during
1182 // incremental sweeping, while also sweeping zones which have finished
1183 // marking.
1184 MainThreadData<bool> markOnBackgroundThreadDuringSweeping;
1185
1186 // Whether any sweeping and decommitting will run on a separate GC helper
1187 // thread.
1188 MainThreadData<bool> useBackgroundThreads;
1189
1190 // Whether we have already discarded JIT code for all collected zones in this
1191 // slice.
1192 MainThreadData<bool> haveDiscardedJITCodeThisSlice;
1193
1194#ifdef DEBUG1
1195 /* Shutdown has started. Further collections must be shutdown collections. */
1196 MainThreadData<bool> hadShutdownGC;
1197#endif
1198
1199 /* Singly linked list of zones to be swept in the background. */
1200 HelperThreadLockData<ZoneList> backgroundSweepZones;
1201
1202 /*
1203 * Whether to trigger a GC slice after a background task is complete, so that
1204 * the collector can continue or finsish collecting. This is only used for the
1205 * tasks that run concurrently with the mutator, which are background
1206 * finalization and background decommit.
1207 */
1208 HelperThreadLockData<bool> requestSliceAfterBackgroundTask;
1209
1210 /*
1211 * Free LIFO blocks are transferred to these allocators before being freed on
1212 * a background thread.
1213 */
1214 HelperThreadLockData<LifoAlloc> lifoBlocksToFree;
1215 MainThreadData<LifoAlloc> lifoBlocksToFreeAfterFullMinorGC;
1216 MainThreadData<LifoAlloc> lifoBlocksToFreeAfterNextMinorGC;
1217 HelperThreadLockData<Nursery::BufferSet> buffersToFreeAfterMinorGC;
1218
1219 /* Index of current sweep group (for stats). */
1220 MainThreadData<unsigned> sweepGroupIndex;
1221
1222 /*
1223 * Incremental sweep state.
1224 */
1225 MainThreadData<JS::Zone*> sweepGroups;
1226 MainThreadOrGCTaskData<JS::Zone*> currentSweepGroup;
1227 MainThreadData<UniquePtr<SweepAction>> sweepActions;
1228 MainThreadOrGCTaskData<JS::Zone*> sweepZone;
1229 MainThreadOrGCTaskData<AllocKind> sweepAllocKind;
1230 MainThreadData<mozilla::Maybe<AtomsTable::SweepIterator>> maybeAtomsToSweep;
1231 MainThreadOrGCTaskData<mozilla::Maybe<WeakCacheSweepIterator>>
1232 weakCachesToSweep;
1233 MainThreadData<bool> abortSweepAfterCurrentGroup;
1234 MainThreadOrGCTaskData<IncrementalProgress> sweepMarkResult;
1235
1236 /*
1237 * During incremental foreground finalization, we may have a list of arenas of
1238 * the current AllocKind and Zone whose contents have been finalized but which
1239 * have not yet been merged back into the main arena lists.
1240 */
1241 MainThreadOrGCTaskData<JS::Zone*> foregroundFinalizedZone;
1242 MainThreadOrGCTaskData<AllocKind> foregroundFinalizedAllocKind;
1243 MainThreadData<mozilla::Maybe<SortedArenaList>> foregroundFinalizedArenas;
1244
1245#ifdef DEBUG1
1246 /*
1247 * List of objects to mark at the beginning of a GC for testing purposes. May
1248 * also contain string directives to change mark color or wait until different
1249 * phases of the GC.
1250 *
1251 * This is a WeakCache because not everything in this list is guaranteed to
1252 * end up marked (eg if you insert an object from an already-processed sweep
1253 * group in the middle of an incremental GC). Also, the mark queue is not
1254 * used during shutdown GCs. In either case, unmarked objects may need to be
1255 * discarded.
1256 */
1257 JS::WeakCache<GCVector<HeapPtr<JS::Value>, 0, SystemAllocPolicy>>
1258 testMarkQueue;
1259
1260 /* Position within the test mark queue. */
1261 size_t queuePos = 0;
1262
1263 /* The test marking queue might want to be marking a particular color. */
1264 mozilla::Maybe<js::gc::MarkColor> queueMarkColor;
1265
1266 // During gray marking, delay AssertCellIsNotGray checks by
1267 // recording the cell pointers here and checking after marking has
1268 // finished.
1269 MainThreadData<Vector<const Cell*, 0, SystemAllocPolicy>>
1270 cellsToAssertNotGray;
1271 friend void js::gc::detail::AssertCellIsNotGray(const Cell*);
1272#endif
1273
1274 friend class SweepGroupsIter;
1275
1276 /*
1277 * Incremental compacting state.
1278 */
1279 MainThreadData<bool> startedCompacting;
1280 MainThreadData<ZoneList> zonesToMaybeCompact;
1281 MainThreadData<size_t> zonesCompacted;
1282#ifdef DEBUG1
1283 GCLockData<Arena*> relocatedArenasToRelease;
1284#endif
1285
1286#ifdef JS_GC_ZEAL1
1287 MainThreadData<MarkingValidator*> markingValidator;
1288#endif
1289
1290 /*
1291 * Default budget for incremental GC slice. See js/SliceBudget.h.
1292 *
1293 * JSGC_SLICE_TIME_BUDGET_MS
1294 * pref: javascript.options.mem.gc_incremental_slice_ms,
1295 */
1296 MainThreadData<int64_t> defaultTimeBudgetMS_;
1297
1298 /*
1299 * Whether compacting GC is enabled globally.
1300 *
1301 * JSGC_COMPACTING_ENABLED
1302 * pref: javascript.options.mem.gc_compacting
1303 */
1304 MainThreadData<bool> compactingEnabled;
1305
1306 /*
1307 * Whether generational GC is enabled globally.
1308 *
1309 * JSGC_NURSERY_ENABLED
1310 * pref: javascript.options.mem.gc_generational
1311 */
1312 MainThreadData<bool> nurseryEnabled;
1313
1314 /*
1315 * Whether parallel marking is enabled globally.
1316 *
1317 * JSGC_PARALLEL_MARKING_ENABLED
1318 * pref: javascript.options.mem.gc_parallel_marking
1319 */
1320 MainThreadData<bool> parallelMarkingEnabled;
1321
1322 MainThreadData<bool> rootsRemoved;
1323
1324 /*
1325 * These options control the zealousness of the GC. At every allocation,
1326 * nextScheduled is decremented. When it reaches zero we do a full GC.
1327 *
1328 * At this point, if zeal_ is one of the types that trigger periodic
1329 * collection, then nextScheduled is reset to the value of zealFrequency.
1330 * Otherwise, no additional GCs take place.
1331 *
1332 * You can control these values in several ways:
1333 * - Set the JS_GC_ZEAL environment variable
1334 * - Call gczeal() or schedulegc() from inside shell-executed JS code
1335 * (see the help for details)
1336 *
1337 * If gcZeal_ == 1 then we perform GCs in select places (during MaybeGC and
1338 * whenever we are notified that GC roots have been removed). This option is
1339 * mainly useful to embedders.
1340 *
1341 * We use zeal_ == 4 to enable write barrier verification. See the comment
1342 * in gc/Verifier.cpp for more information about this.
1343 *
1344 * zeal_ values from 8 to 10 periodically run different types of
1345 * incremental GC.
1346 *
1347 * zeal_ value 14 performs periodic shrinking collections.
1348 */
1349#ifdef JS_GC_ZEAL1
1350 static_assert(size_t(ZealMode::Count) <= 32,
1351 "Too many zeal modes to store in a uint32_t");
1352 MainThreadData<uint32_t> zealModeBits;
1353 MainThreadData<int> zealFrequency;
1354 MainThreadData<int> nextScheduled;
1355 MainThreadData<bool> deterministicOnly;
1356 MainThreadData<int> zealSliceBudget;
1357 MainThreadData<size_t> maybeMarkStackLimit;
1358
1359 MainThreadData<PersistentRooted<GCVector<JSObject*, 0, SystemAllocPolicy>>>
1360 selectedForMarking;
1361#endif
1362
1363 MainThreadData<bool> fullCompartmentChecks;
1364
1365 MainThreadData<uint32_t> gcCallbackDepth;
1366
1367 MainThreadData<Callback<JSGCCallback>> gcCallback;
1368 MainThreadData<Callback<JS::DoCycleCollectionCallback>>
1369 gcDoCycleCollectionCallback;
1370 MainThreadData<Callback<JSObjectsTenuredCallback>> tenuredCallback;
1371 MainThreadData<CallbackVector<JSFinalizeCallback>> finalizeCallbacks;
1372 MainThreadOrGCTaskData<Callback<JSHostCleanupFinalizationRegistryCallback>>
1373 hostCleanupFinalizationRegistryCallback;
1374 MainThreadData<CallbackVector<JSWeakPointerZonesCallback>>
1375 updateWeakPointerZonesCallbacks;
1376 MainThreadData<CallbackVector<JSWeakPointerCompartmentCallback>>
1377 updateWeakPointerCompartmentCallbacks;
1378 MainThreadData<CallbackVector<JS::GCNurseryCollectionCallback>>
1379 nurseryCollectionCallbacks;
1380
1381 /*
1382 * The trace operations to trace embedding-specific GC roots. One is for
1383 * tracing through black roots and the other is for tracing through gray
1384 * roots. The black/gray distinction is only relevant to the cycle
1385 * collector.
1386 */
1387 MainThreadData<CallbackVector<JSTraceDataOp>> blackRootTracers;
1388 MainThreadOrGCTaskData<Callback<JSGrayRootsTracer>> grayRootTracer;
1389
1390 /* Always preserve JIT code during GCs, for testing. */
1391 MainThreadData<bool> alwaysPreserveCode;
1392
1393 /* Count of the number of zones that are currently in page load. */
1394 MainThreadData<size_t> inPageLoadCount;
1395
1396 MainThreadData<bool> lowMemoryState;
1397
1398 /*
1399 * General purpose GC lock, used for synchronising operations on
1400 * arenas and during parallel marking.
1401 */
1402 friend class js::AutoLockGC;
1403 friend class js::AutoLockGCBgAlloc;
1404 Mutex lock MOZ_UNANNOTATED;
1405
1406 /*
1407 * Lock used to synchronise access to the store buffer during parallel
1408 * sweeping.
1409 */
1410 Mutex storeBufferLock MOZ_UNANNOTATED;
1411
1412 /* Lock used to synchronise access to delayed marking state. */
1413 Mutex delayedMarkingLock MOZ_UNANNOTATED;
1414
1415 friend class BackgroundSweepTask;
1416 friend class BackgroundFreeTask;
1417
1418 BackgroundAllocTask allocTask;
1419 BackgroundUnmarkTask unmarkTask;
1420 BackgroundMarkTask markTask;
1421 BackgroundSweepTask sweepTask;
1422 BackgroundFreeTask freeTask;
1423 BackgroundDecommitTask decommitTask;
1424
1425 MainThreadData<Nursery> nursery_;
1426
1427 // The store buffer used to track tenured to nursery edges for generational
1428 // GC. This is accessed off main thread when sweeping WeakCaches.
1429 MainThreadOrGCTaskData<gc::StoreBuffer> storeBuffer_;
1430
1431 mozilla::TimeStamp lastLastDitchTime;
1432
1433 // The last time per-zone allocation rates were updated.
1434 MainThreadData<mozilla::TimeStamp> lastAllocRateUpdateTime;
1435
1436 // Total collector time since per-zone allocation rates were last updated.
1437 MainThreadData<mozilla::TimeDuration> collectorTimeSinceAllocRateUpdate;
1438
1439 friend class MarkingValidator;
1440 friend class AutoEnterIteration;
1441};
1442
1443#ifndef JS_GC_ZEAL1
1444inline bool GCRuntime::hasZealMode(ZealMode mode) const { return false; }
1445inline void GCRuntime::clearZealMode(ZealMode mode) {}
1446inline bool GCRuntime::needZealousGC() { return false; }
1447inline bool GCRuntime::zealModeControlsYieldPoint() const { return false; }
1448#endif
1449
1450/* Prevent compartments and zones from being collected during iteration. */
1451class MOZ_RAII AutoEnterIteration {
1452 GCRuntime* gc;
1453
1454 public:
1455 explicit AutoEnterIteration(GCRuntime* gc_) : gc(gc_) {
1456 ++gc->numActiveZoneIters;
1457 }
1458
1459 ~AutoEnterIteration() {
1460 MOZ_ASSERT(gc->numActiveZoneIters)do { static_assert( mozilla::detail::AssertionConditionType<
decltype(gc->numActiveZoneIters)>::isValid, "invalid assertion condition"
); if ((__builtin_expect(!!(!(!!(gc->numActiveZoneIters)))
, 0))) { do { } while (false); MOZ_ReportAssertionFailure("gc->numActiveZoneIters"
, "/var/lib/jenkins/workspace/firefox-scan-build/js/src/gc/GCRuntime.h"
, 1460); AnnotateMozCrashReason("MOZ_ASSERT" "(" "gc->numActiveZoneIters"
")"); do { *((volatile int*)__null) = 1460; __attribute__((nomerge
)) ::abort(); } while (false); } } while (false);
1461 --gc->numActiveZoneIters;
1462 }
1463};
1464
1465bool IsCurrentlyAnimating(const mozilla::TimeStamp& lastAnimationTime,
1466 const mozilla::TimeStamp& currentTime);
1467
1468} /* namespace gc */
1469} /* namespace js */
1470
1471#endif