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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
commit43a97878ce14b72f0981164f87f2e35e14151312 (patch)
tree620249daf56c0258faa40cbdcf9cfba06de2a846 /js/src/gc/Barrier.cpp
parentInitial commit. (diff)
downloadfirefox-43a97878ce14b72f0981164f87f2e35e14151312.tar.xz
firefox-43a97878ce14b72f0981164f87f2e35e14151312.zip
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'js/src/gc/Barrier.cpp')
-rw-r--r--js/src/gc/Barrier.cpp229
1 files changed, 229 insertions, 0 deletions
diff --git a/js/src/gc/Barrier.cpp b/js/src/gc/Barrier.cpp
new file mode 100644
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+++ b/js/src/gc/Barrier.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "gc/Barrier.h"
+
+#include "gc/Marking.h"
+#include "jit/JitContext.h"
+#include "js/HashTable.h"
+#include "js/shadow/Zone.h" // JS::shadow::Zone
+#include "js/Value.h"
+#include "vm/BigIntType.h" // JS::BigInt
+#include "vm/EnvironmentObject.h"
+#include "vm/GeneratorObject.h"
+#include "vm/JSObject.h"
+#include "vm/PropMap.h"
+#include "wasm/WasmJS.h"
+
+#include "gc/Zone-inl.h"
+
+namespace js {
+
+bool RuntimeFromMainThreadIsHeapMajorCollecting(JS::shadow::Zone* shadowZone) {
+ MOZ_ASSERT(
+ CurrentThreadCanAccessRuntime(shadowZone->runtimeFromMainThread()));
+ return JS::RuntimeHeapIsMajorCollecting();
+}
+
+#ifdef DEBUG
+
+bool IsMarkedBlack(JSObject* obj) { return obj->isMarkedBlack(); }
+
+bool HeapSlot::preconditionForSet(NativeObject* owner, Kind kind,
+ uint32_t slot) const {
+ if (kind == Slot) {
+ return &owner->getSlotRef(slot) == this;
+ }
+
+ uint32_t numShifted = owner->getElementsHeader()->numShiftedElements();
+ MOZ_ASSERT(slot >= numShifted);
+ return &owner->getDenseElement(slot - numShifted) == (const Value*)this;
+}
+
+void HeapSlot::assertPreconditionForPostWriteBarrier(
+ NativeObject* obj, Kind kind, uint32_t slot, const Value& target) const {
+ if (kind == Slot) {
+ MOZ_ASSERT(obj->getSlotAddressUnchecked(slot)->get() == target);
+ } else {
+ uint32_t numShifted = obj->getElementsHeader()->numShiftedElements();
+ MOZ_ASSERT(slot >= numShifted);
+ MOZ_ASSERT(
+ static_cast<HeapSlot*>(obj->getDenseElements() + (slot - numShifted))
+ ->get() == target);
+ }
+
+ if (!obj->zone()->isGCPreparing()) {
+ AssertTargetIsNotGray(obj);
+ }
+}
+
+bool CurrentThreadIsIonCompiling() {
+ jit::JitContext* jcx = jit::MaybeGetJitContext();
+ return jcx && jcx->inIonBackend();
+}
+
+#endif // DEBUG
+
+template <typename T>
+/* static */ bool MovableCellHasher<T>::hasHash(const Lookup& l) {
+ if (!l) {
+ return true;
+ }
+
+ return l->zoneFromAnyThread()->hasUniqueId(l);
+}
+
+template <typename T>
+/* static */ bool MovableCellHasher<T>::ensureHash(const Lookup& l) {
+ if (!l) {
+ return true;
+ }
+
+ uint64_t unusedId;
+ return l->zoneFromAnyThread()->getOrCreateUniqueId(l, &unusedId);
+}
+
+template <typename T>
+/* static */ HashNumber MovableCellHasher<T>::hash(const Lookup& l) {
+ if (!l) {
+ return 0;
+ }
+
+ // We have to access the zone from-any-thread here: a worker thread may be
+ // cloning a self-hosted object from the main runtime's self- hosting zone
+ // into another runtime. The zone's uid lock will protect against multiple
+ // workers doing this simultaneously.
+ MOZ_ASSERT(CurrentThreadCanAccessZone(l->zoneFromAnyThread()) ||
+ CurrentThreadIsPerformingGC());
+
+ return l->zoneFromAnyThread()->getHashCodeInfallible(l);
+}
+
+template <typename T>
+/* static */ bool MovableCellHasher<T>::match(const Key& k, const Lookup& l) {
+ // Return true if both are null or false if only one is null.
+ if (!k) {
+ return !l;
+ }
+ if (!l) {
+ return false;
+ }
+
+ MOZ_ASSERT(k);
+ MOZ_ASSERT(l);
+ MOZ_ASSERT(CurrentThreadCanAccessZone(l->zoneFromAnyThread()) ||
+ CurrentThreadIsPerformingGC());
+
+ Zone* zone = k->zoneFromAnyThread();
+ if (zone != l->zoneFromAnyThread()) {
+ return false;
+ }
+
+#ifdef DEBUG
+ // Incremental table sweeping means that existing table entries may no
+ // longer have unique IDs. We fail the match in that case and the entry is
+ // removed from the table later on.
+ if (!zone->hasUniqueId(k)) {
+ Key key = k;
+ MOZ_ASSERT(IsAboutToBeFinalizedUnbarriered(key));
+ }
+ MOZ_ASSERT(zone->hasUniqueId(l));
+#endif
+
+ uint64_t keyId;
+ if (!zone->maybeGetUniqueId(k, &keyId)) {
+ // Key is dead and cannot match lookup which must be live.
+ return false;
+ }
+
+ return keyId == zone->getUniqueIdInfallible(l);
+}
+
+#if !MOZ_IS_GCC
+template struct JS_PUBLIC_API MovableCellHasher<JSObject*>;
+#endif
+
+template struct JS_PUBLIC_API MovableCellHasher<AbstractGeneratorObject*>;
+template struct JS_PUBLIC_API MovableCellHasher<EnvironmentObject*>;
+template struct JS_PUBLIC_API MovableCellHasher<GlobalObject*>;
+template struct JS_PUBLIC_API MovableCellHasher<JSScript*>;
+template struct JS_PUBLIC_API MovableCellHasher<BaseScript*>;
+template struct JS_PUBLIC_API MovableCellHasher<PropMap*>;
+template struct JS_PUBLIC_API MovableCellHasher<ScriptSourceObject*>;
+template struct JS_PUBLIC_API MovableCellHasher<SavedFrame*>;
+template struct JS_PUBLIC_API MovableCellHasher<WasmInstanceObject*>;
+
+} // namespace js
+
+// Post-write barrier, used by the C++ Heap<T> implementation.
+
+JS_PUBLIC_API void JS::HeapObjectPostWriteBarrier(JSObject** objp,
+ JSObject* prev,
+ JSObject* next) {
+ MOZ_ASSERT(objp);
+ js::InternalBarrierMethods<JSObject*>::postBarrier(objp, prev, next);
+}
+
+JS_PUBLIC_API void JS::HeapStringPostWriteBarrier(JSString** strp,
+ JSString* prev,
+ JSString* next) {
+ MOZ_ASSERT(strp);
+ js::InternalBarrierMethods<JSString*>::postBarrier(strp, prev, next);
+}
+
+JS_PUBLIC_API void JS::HeapBigIntPostWriteBarrier(JS::BigInt** bip,
+ JS::BigInt* prev,
+ JS::BigInt* next) {
+ MOZ_ASSERT(bip);
+ js::InternalBarrierMethods<JS::BigInt*>::postBarrier(bip, prev, next);
+}
+
+JS_PUBLIC_API void JS::HeapValuePostWriteBarrier(JS::Value* valuep,
+ const Value& prev,
+ const Value& next) {
+ MOZ_ASSERT(valuep);
+ js::InternalBarrierMethods<JS::Value>::postBarrier(valuep, prev, next);
+}
+
+// Combined pre- and post-write barriers, used by the rust Heap<T>
+// implementation.
+
+JS_PUBLIC_API void JS::HeapObjectWriteBarriers(JSObject** objp, JSObject* prev,
+ JSObject* next) {
+ MOZ_ASSERT(objp);
+ js::InternalBarrierMethods<JSObject*>::preBarrier(prev);
+ js::InternalBarrierMethods<JSObject*>::postBarrier(objp, prev, next);
+}
+
+JS_PUBLIC_API void JS::HeapStringWriteBarriers(JSString** strp, JSString* prev,
+ JSString* next) {
+ MOZ_ASSERT(strp);
+ js::InternalBarrierMethods<JSString*>::preBarrier(prev);
+ js::InternalBarrierMethods<JSString*>::postBarrier(strp, prev, next);
+}
+
+JS_PUBLIC_API void JS::HeapBigIntWriteBarriers(JS::BigInt** bip,
+ JS::BigInt* prev,
+ JS::BigInt* next) {
+ MOZ_ASSERT(bip);
+ js::InternalBarrierMethods<JS::BigInt*>::preBarrier(prev);
+ js::InternalBarrierMethods<JS::BigInt*>::postBarrier(bip, prev, next);
+}
+
+JS_PUBLIC_API void JS::HeapScriptWriteBarriers(JSScript** scriptp,
+ JSScript* prev, JSScript* next) {
+ MOZ_ASSERT(scriptp);
+ js::InternalBarrierMethods<JSScript*>::preBarrier(prev);
+ js::InternalBarrierMethods<JSScript*>::postBarrier(scriptp, prev, next);
+}
+
+JS_PUBLIC_API void JS::HeapValueWriteBarriers(JS::Value* valuep,
+ const Value& prev,
+ const Value& next) {
+ MOZ_ASSERT(valuep);
+ js::InternalBarrierMethods<JS::Value>::preBarrier(prev);
+ js::InternalBarrierMethods<JS::Value>::postBarrier(valuep, prev, next);
+}