Ejemplo n.º 1
0
static inline void
MarkExactStackRooters(JSTracer *trc, Rooted<void*> rooter, ThingRootKind kind)
{
    Rooted<void*> *rooter = cx->thingGCRooters[i];
    while (rooter) {
        MarkExactStackRoot(trc, rooter, ThingRootKind(i));
        rooter = rooter->previous();
    }
}
Ejemplo n.º 2
0
static inline void
MarkExactStackRootList(JSTracer* trc, Source* s, const char* name)
{
    Rooted<T>* rooter = s->roots.template gcRooters<T>();
    while (rooter) {
        T* addr = rooter->address();
        TraceFn(trc, addr, name);
        rooter = rooter->previous();
    }
}
Ejemplo n.º 3
0
static inline void
MarkExactStackRootList(JSTracer *trc, Source *s, const char *name)
{
    Rooted<T> *rooter = s->template gcRooters<T>();
    while (rooter) {
        T *addr = rooter->address();
        if (!IgnoreExactRoot(addr))
            MarkFunc(trc, addr, name);
        rooter = rooter->previous();
    }
}
Ejemplo n.º 4
0
static void
GatherRooters(Vector<Rooter, 0, SystemAllocPolicy> &rooters,
              Rooted<void*> **thingGCRooters,
              unsigned thingRootKind)
{
    Rooted<void*> *rooter = thingGCRooters[thingRootKind];
    while (rooter) {
        Rooter r = { rooter, ThingRootKind(thingRootKind) };
        JS_ALWAYS_TRUE(rooters.append(r));
        rooter = rooter->previous();
    }
}
Ejemplo n.º 5
0
void
JS::CheckStackRoots(JSContext *cx)
{
    JSRuntime *rt = cx->runtime;

    if (rt->gcZeal_ != ZealStackRootingSafeValue && rt->gcZeal_ != ZealStackRootingValue)
        return;
    if (rt->gcZeal_ == ZealStackRootingSafeValue && !rt->gcExactScanningEnabled)
        return;

    // If this assertion fails, it means that an AutoAssertNoGC was placed
    // around code that could trigger GC, and is therefore wrong. The
    // AutoAssertNoGC should be removed and the code it was guarding should be
    // modified to properly root any gcthings, and very possibly any code
    // calling that function should also be modified if it was improperly
    // assuming that GC could not happen at all within the called function.
    // (The latter may not apply if the AutoAssertNoGC only protected a portion
    // of a function, so the callers were already assuming that GC could
    // happen.)
    JS_ASSERT(!InNoGCScope());

    // GCs can't happen when analysis/inference/compilation are active.
    if (cx->compartment->activeAnalysis)
        return;

    // Can switch to the atoms compartment during analysis.
    if (IsAtomsCompartment(cx->compartment)) {
        for (CompartmentsIter c(rt); !c.done(); c.next()) {
            if (c.get()->activeAnalysis)
                return;
        }
    }

    AutoCopyFreeListToArenas copy(rt);

    ConservativeGCData *cgcd = &rt->conservativeGC;
    cgcd->recordStackTop();

    JS_ASSERT(cgcd->hasStackToScan());
    uintptr_t *stackMin, *stackEnd;
#if JS_STACK_GROWTH_DIRECTION > 0
    stackMin = rt->nativeStackBase;
    stackEnd = cgcd->nativeStackTop;
#else
    stackMin = cgcd->nativeStackTop + 1;
    stackEnd = reinterpret_cast<uintptr_t *>(rt->nativeStackBase);
#endif

    // Gather up all of the rooters
    Vector< Rooter, 0, SystemAllocPolicy> rooters;
    for (unsigned i = 0; i < THING_ROOT_LIMIT; i++) {
        Rooted<void*> *rooter = rt->mainThread.thingGCRooters[i];
        while (rooter) {
            Rooter r = { rooter, ThingRootKind(i) };
            JS_ALWAYS_TRUE(rooters.append(r));
            rooter = rooter->previous();
        }
        for (ContextIter cx(rt); !cx.done(); cx.next()) {
            rooter = cx->thingGCRooters[i];
            while (rooter) {
                Rooter r = { rooter, ThingRootKind(i) };
                JS_ALWAYS_TRUE(rooters.append(r));
                rooter = rooter->previous();
            }
        }
    }

    if (SuppressCheckRoots(rooters))
        return;

    // Truncate stackEnd to just after the address of the youngest
    // already-scanned rooter on the stack, to avoid re-scanning the rest of
    // the stack.
    void *firstScanned = NULL;
    for (Rooter *p = rooters.begin(); p != rooters.end(); p++) {
        if (p->rooter->scanned) {
            uintptr_t *addr = reinterpret_cast<uintptr_t*>(p->rooter);
#if JS_STACK_GROWTH_DIRECTION < 0
            if (stackEnd > addr)
#else
            if (stackEnd < addr)
#endif
            {
                stackEnd = addr;
                firstScanned = p->rooter;
            }
        }
    }

    // Partition the stack by the already-scanned start address. Put everything
    // that needs to be searched at the end of the vector.
    Rooter *firstToScan = rooters.begin();
    if (firstScanned) {
        for (Rooter *p = rooters.begin(); p != rooters.end(); p++) {
#if JS_STACK_GROWTH_DIRECTION < 0
            if (p->rooter >= firstScanned)
#else
            if (p->rooter <= firstScanned)
#endif
            {
                Swap(*firstToScan, *p);
                ++firstToScan;
            }
        }
    }

    JS_ASSERT(stackMin <= stackEnd);
    CheckStackRootsRangeAndSkipIon(rt, stackMin, stackEnd, firstToScan, rooters.end());
    CheckStackRootsRange(rt, cgcd->registerSnapshot.words,
                         ArrayEnd(cgcd->registerSnapshot.words),
                         firstToScan, rooters.end());

    // Mark all rooters as scanned
    for (Rooter *p = rooters.begin(); p != rooters.end(); p++)
        p->rooter->scanned = true;
}