DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=8 sts=4 et sw=4 tw=99:
 * 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 "jsweakmap.h"

#include <string.h>

#include "jsapi.h"
#include "jscntxt.h"
#include "jsfriendapi.h"
#include "jsobj.h"
#include "jswrapper.h"

#include "js/GCAPI.h"
#include "vm/GlobalObject.h"

#include "jsobjinlines.h"

using namespace js;
using namespace js::gc;

WeakMapBase::WeakMapBase(JSObject* memOf, Zone* zone)
  : memberOf(memOf),
    zone(zone),
    marked(false)
{
    MOZ_ASSERT_IF(memberOf, memberOf->compartment()->zone() == zone);
}

WeakMapBase::~WeakMapBase()
{
    MOZ_ASSERT(CurrentThreadIsGCSweeping() || CurrentThreadIsHandlingInitFailure());
}

void
WeakMapBase::unmarkZone(JS::Zone* zone)
{
    for (WeakMapBase* m : zone->gcWeakMapList)
        m->marked = false;
}

void
WeakMapBase::markAll(JS::Zone* zone, JSTracer* tracer)
{
    MOZ_ASSERT(tracer->weakMapAction() != DoNotTraceWeakMaps);
    for (WeakMapBase* m : zone->gcWeakMapList) {
        m->trace(tracer);
        if (m->memberOf)
            TraceEdge(tracer, &m->memberOf, "memberOf");
    }
}

bool
WeakMapBase::markZoneIteratively(JS::Zone* zone, JSTracer* tracer)
{
    bool markedAny = false;
    for (WeakMapBase* m : zone->gcWeakMapList) {
        if (m->marked && m->traceEntries(tracer))
            markedAny = true;
    }
    return markedAny;
}

bool
WeakMapBase::findInterZoneEdges(JS::Zone* zone)
{
    for (WeakMapBase* m : zone->gcWeakMapList) {
        if (!m->findZoneEdges())
            return false;
    }
    return true;
}

void
WeakMapBase::sweepZone(JS::Zone* zone)
{
    for (WeakMapBase* m = zone->gcWeakMapList.getFirst(); m; ) {
        WeakMapBase* next = m->getNext();
        if (m->marked) {
            m->sweep();
        } else {
            /* Destroy the hash map now to catch any use after this point. */
            m->finish();
            m->removeFrom(zone->gcWeakMapList);
        }
        m = next;
    }

#ifdef DEBUG
    for (WeakMapBase* m : zone->gcWeakMapList) {
        MOZ_ASSERT(m->isInList() && m->marked);
    }
#endif
}

void
WeakMapBase::traceAllMappings(WeakMapTracer* tracer)
{
    JSRuntime* rt = tracer->runtime;
    for (ZonesIter zone(rt, SkipAtoms); !zone.done(); zone.next()) {
        for (WeakMapBase* m : zone->gcWeakMapList) {
            // The WeakMapTracer callback is not allowed to GC.
            JS::AutoSuppressGCAnalysis nogc;
            m->traceMappings(tracer);
        }
    }
}

bool
WeakMapBase::saveZoneMarkedWeakMaps(JS::Zone* zone, WeakMapSet& markedWeakMaps)
{
    for (WeakMapBase* m : zone->gcWeakMapList) {
        if (m->marked && !markedWeakMaps.put(m))
            return false;
    }
    return true;
}

void
WeakMapBase::restoreMarkedWeakMaps(WeakMapSet& markedWeakMaps)
{
    for (WeakMapSet::Range r = markedWeakMaps.all(); !r.empty(); r.popFront()) {
        WeakMapBase* map = r.front();
        MOZ_ASSERT(map->zone->isGCMarking());
        MOZ_ASSERT(!map->marked);
        map->marked = true;
    }
}

bool
ObjectValueMap::findZoneEdges()
{
    /*
     * For unmarked weakmap keys with delegates in a different zone, add a zone
     * edge to ensure that the delegate zone finishes marking before the key
     * zone.
     */
    JS::AutoSuppressGCAnalysis nogc;
    for (Range r = all(); !r.empty(); r.popFront()) {
        JSObject* key = r.front().key();
        if (key->asTenured().isMarked(BLACK) && !key->asTenured().isMarked(GRAY))
            continue;
        JSWeakmapKeyDelegateOp op = key->getClass()->ext.weakmapKeyDelegateOp;
        if (!op)
            continue;
        JSObject* delegate = op(key);
        if (!delegate)
            continue;
        Zone* delegateZone = delegate->zone();
        if (delegateZone == zone)
            continue;
        if (!delegateZone->gcZoneGroupEdges.put(key->zone()))
            return false;
    }
    return true;
}

ObjectWeakMap::ObjectWeakMap(JSContext* cx)
  : map(cx, nullptr)
{}

bool
ObjectWeakMap::init()
{
    return map.init();
}

JSObject*
ObjectWeakMap::lookup(const JSObject* obj)
{
    MOZ_ASSERT(map.initialized());
    if (ObjectValueMap::Ptr p = map.lookup(const_cast<JSObject*>(obj)))
        return &p->value().toObject();
    return nullptr;
}

bool
ObjectWeakMap::add(JSContext* cx, JSObject* obj, JSObject* target)
{
    MOZ_ASSERT(obj && target);
    MOZ_ASSERT(map.initialized());

    MOZ_ASSERT(!map.has(obj));
    if (!map.put(obj, ObjectValue(*target))) {
        ReportOutOfMemory(cx);
        return false;
    }
    if (IsInsideNursery(obj))
        cx->runtime()->gc.storeBuffer.putGeneric(StoreBufferRef(&map, obj));

    return true;
}

void
ObjectWeakMap::clear()
{
    MOZ_ASSERT(map.initialized());
    map.clear();
}

void
ObjectWeakMap::trace(JSTracer* trc)
{
    MOZ_ASSERT(map.initialized());
    map.trace(trc);
}

size_t
ObjectWeakMap::sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf)
{
    MOZ_ASSERT(map.initialized());
    return map.sizeOfExcludingThis(mallocSizeOf);
}

#ifdef JSGC_HASH_TABLE_CHECKS
void
ObjectWeakMap::checkAfterMovingGC()
{
    MOZ_ASSERT(map.initialized());
    for (ObjectValueMap::Range r = map.all(); !r.empty(); r.popFront()) {
        CheckGCThingAfterMovingGC(r.front().key().get());
        CheckGCThingAfterMovingGC(&r.front().value().toObject());
    }
}
#endif // JSGC_HASH_TABLE_CHECKS