Bug 650161 - Enable compacting GC on GC_SHRINK collections r=terrence r=glandium

js/src/configure.in

@@ -3052,18 +3052,6 @@ MOZ_ARG_WITH_STRING(wrap-malloc,
 [  --with-wrap-malloc=DIR  Location of malloc wrapper library],
     WRAP_LDFLAGS="${WRAP_LDFLAGS} $withval")
 
-dnl ========================================================
-dnl = Use compacting GC
-dnl ========================================================
-dnl Compact the heap by moving GC things when doing a shrinking colletion.
-MOZ_ARG_ENABLE_BOOL(gccompacting,
-[  --enable-gccompacting   Compact the heap by moving GC things],
-    JSGC_COMPACTING=1,
-    JSGC_COMPACTING= )
-if test -n "$JSGC_COMPACTING"; then
-    AC_DEFINE(JSGC_COMPACTING)
-fi
-
 dnl ========================================================
 dnl = Use a smaller chunk size for GC chunks
 dnl ========================================================

js/src/gc/GCInternals.h

@@ -143,7 +143,6 @@ void
 CheckHashTablesAfterMovingGC(JSRuntime *rt);
 #endif
 
-#ifdef JSGC_COMPACTING
 struct MovingTracer : JSTracer {
     explicit MovingTracer(JSRuntime *rt) : JSTracer(rt, Visit, TraceWeakMapKeysValues) {}
 
@@ -152,7 +151,6 @@ struct MovingTracer : JSTracer {
         return trc->callback == Visit;
     }
 };
-#endif
 
 } /* namespace gc */
 } /* namespace js */

js/src/gc/GCRuntime.h

@@ -34,11 +34,8 @@ struct FinalizePhase;
 class MarkingValidator;
 struct AutoPrepareForTracing;
 class AutoTraceSession;
-
-#ifdef JSGC_COMPACTING
 struct ArenasToUpdate;
 struct MovingTracer;
-#endif
 
 class ChunkPool
 {
@@ -297,11 +294,7 @@ class GCRuntime
     bool isHeapMajorCollecting() { return heapState == js::MajorCollecting; }
     bool isHeapMinorCollecting() { return heapState == js::MinorCollecting; }
     bool isHeapCollecting() { return isHeapMajorCollecting() || isHeapMinorCollecting(); }
-#ifdef JSGC_COMPACTING
     bool isHeapCompacting() { return isHeapMajorCollecting() && state() == COMPACT; }
-#else
-    bool isHeapCompacting() { return false; }
-#endif
 
     bool triggerGC(JS::gcreason::Reason reason);
     void maybeAllocTriggerZoneGC(Zone *zone, const AutoLockGC &lock);
@@ -437,11 +430,9 @@ class GCRuntime
     void disableGenerationalGC();
     void enableGenerationalGC();
 
-#ifdef JSGC_COMPACTING
     void disableCompactingGC();
     void enableCompactingGC();
     bool isCompactingGCEnabled();
-#endif
 
     void setGrayRootsTracer(JSTraceDataOp traceOp, void *data);
     bool addBlackRootsTracer(JSTraceDataOp traceOp, void *data);
@@ -604,7 +595,6 @@ class GCRuntime
     void assertBackgroundSweepingFinished();
     bool shouldCompact();
     bool compactPhase(bool lastGC);
-#ifdef JSGC_COMPACTING
     void sweepTypesAfterCompacting(Zone *zone);
     void sweepZoneAfterCompacting(Zone *zone);
     ArenaHeader *relocateArenas();
@@ -616,7 +606,6 @@ class GCRuntime
 #ifdef DEBUG
     void protectRelocatedArenas(ArenaHeader *relocatedList);
     void unprotectRelocatedArenas(ArenaHeader *relocatedList);
-#endif
 #endif
     void finishCollection();
 
@@ -811,13 +800,11 @@ class GCRuntime
      */
     unsigned generationalDisabled;
 
-#ifdef JSGC_COMPACTING
     /*
      * Some code cannot tolerate compacting GC so it can be disabled with this
      * counter.
      */
     unsigned compactingDisabled;
-#endif
 
     /*
      * This is true if we are in the middle of a brain transplant (e.g.,
@@ -918,9 +905,7 @@ class GCRuntime
 
     size_t noGCOrAllocationCheck;
 
-#ifdef JSGC_COMPACTING
     ArenaHeader* relocatedArenasToRelease;
-#endif
 
 #endif
 

js/src/gc/Heap.h

@@ -642,10 +642,8 @@ struct ArenaHeader
 
     void unmarkAll();
 
-#ifdef JSGC_COMPACTING
     size_t countUsedCells();
     size_t countFreeCells();
-#endif
 };
 static_assert(ArenaZoneOffset == offsetof(ArenaHeader, zone),
               "The hardcoded API zone offset must match the actual offset.");

js/src/gc/Marking.cpp

@@ -161,18 +161,14 @@ CheckMarkedThing(JSTracer *trc, T **thingp)
     T *thing = *thingp;
     MOZ_ASSERT(*thingp);
 
-#ifdef JSGC_COMPACTING
     thing = MaybeForwarded(thing);
-#endif
 
     /* This function uses data that's not available in the nursery. */
     if (IsInsideNursery(thing))
         return;
 
-#ifdef JSGC_COMPACTING
     MOZ_ASSERT_IF(!MovingTracer::IsMovingTracer(trc) && !Nursery::IsMinorCollectionTracer(trc),
                   !IsForwarded(*thingp));
-#endif
 
     /*
      * Permanent atoms are not associated with this runtime, but will be ignored
@@ -184,13 +180,8 @@ CheckMarkedThing(JSTracer *trc, T **thingp)
     Zone *zone = thing->zoneFromAnyThread();
     JSRuntime *rt = trc->runtime();
 
-#ifdef JSGC_COMPACTING
     MOZ_ASSERT_IF(!MovingTracer::IsMovingTracer(trc), CurrentThreadCanAccessZone(zone));
     MOZ_ASSERT_IF(!MovingTracer::IsMovingTracer(trc), CurrentThreadCanAccessRuntime(rt));
-#else
-    MOZ_ASSERT(CurrentThreadCanAccessZone(zone));
-    MOZ_ASSERT(CurrentThreadCanAccessRuntime(rt));
-#endif
 
     MOZ_ASSERT(zone->runtimeFromAnyThread() == trc->runtime());
     MOZ_ASSERT(trc->hasTracingDetails());
@@ -437,10 +428,8 @@ IsMarkedFromAnyThread(T **thingp)
     Zone *zone = (*thingp)->asTenured().zoneFromAnyThread();
     if (!zone->isCollectingFromAnyThread() || zone->isGCFinished())
         return true;
-#ifdef JSGC_COMPACTING
     if (zone->isGCCompacting() && IsForwarded(*thingp))
         *thingp = Forwarded(*thingp);
-#endif
     return (*thingp)->asTenured().isMarked();
 }
 
@@ -481,12 +470,10 @@ IsAboutToBeFinalizedFromAnyThread(T **thingp)
             return false;
         return !thing->asTenured().isMarked();
     }
-#ifdef JSGC_COMPACTING
     else if (zone->isGCCompacting() && IsForwarded(thing)) {
         *thingp = Forwarded(thing);
         return false;
     }
-#endif
 
     return false;
 }
@@ -504,11 +491,10 @@ UpdateIfRelocated(JSRuntime *rt, T **thingp)
         return *thingp;
     }
 
-#ifdef JSGC_COMPACTING
     Zone *zone = (*thingp)->zone();
     if (zone->isGCCompacting() && IsForwarded(*thingp))
         *thingp = Forwarded(*thingp);
-#endif
+
     return *thingp;
 }
 

js/src/js-config.h.in

@@ -31,9 +31,6 @@
 /* Define to 1 if SpiderMonkey should use small chunks. */
 #undef JS_GC_SMALL_CHUNK_SIZE
 
-/* Define to 1 if SpiderMonkey should use Compacting GC. */
-#undef JSGC_COMPACTING
-
 /* Define to 1 if the <endian.h> header is present and
    useable.  See jscpucfg.h.  */
 #undef JS_HAVE_ENDIAN_H

js/src/jsapi-tests/testWeakMap.cpp

@@ -66,10 +66,6 @@ checkSize(JS::HandleObject map, uint32_t expected)
 }
 END_TEST(testWeakMap_basicOperations)
 
-// TODO: this test stores object pointers in a private slot which is not marked
-// and so doesn't work with compacting GC.
-#ifndef JSGC_COMPACTING
-
 BEGIN_TEST(testWeakMap_keyDelegates)
 {
     JS_SetGCParameter(rt, JSGC_MODE, JSGC_MODE_INCREMENTAL);
@@ -253,5 +249,3 @@ checkSize(JS::HandleObject map, uint32_t expected)
     return true;
 }
 END_TEST(testWeakMap_keyDelegates)
-
-#endif

js/src/jscompartment.cpp

@@ -649,8 +649,6 @@ JSCompartment::sweepCrossCompartmentWrappers()
     }
 }
 
-#ifdef JSGC_COMPACTING
-
 void JSCompartment::fixupAfterMovingGC()
 {
     fixupGlobal();
@@ -667,8 +665,6 @@ JSCompartment::fixupGlobal()
         global_.set(MaybeForwarded(global));
 }
 
-#endif // JSGC_COMPACTING
-
 void
 JSCompartment::purge()
 {

js/src/jscompartment.h

@@ -398,12 +398,10 @@ struct JSCompartment
     void purge();
     void clearTables();
 
-#ifdef JSGC_COMPACTING
     void fixupInitialShapeTable();
     void fixupNewTypeObjectTable(js::types::NewTypeObjectTable &table);
     void fixupAfterMovingGC();
     void fixupGlobal();
-#endif
 
     bool hasObjectMetadataCallback() const { return objectMetadataCallback; }
     void setObjectMetadataCallback(js::ObjectMetadataCallback callback);

js/src/jsgc.cpp

@@ -1112,9 +1112,7 @@ GCRuntime::GCRuntime(JSRuntime *rt) :
     sliceBudget(SliceBudget::Unlimited),
     incrementalAllowed(true),
     generationalDisabled(0),
-#ifdef JSGC_COMPACTING
     compactingDisabled(0),
-#endif
     manipulatingDeadZones(false),
     objectsMarkedInDeadZones(0),
     poked(false),
@@ -1134,9 +1132,7 @@ GCRuntime::GCRuntime(JSRuntime *rt) :
 #ifdef DEBUG
     inUnsafeRegion(0),
     noGCOrAllocationCheck(0),
-#ifdef JSGC_COMPACTING
     relocatedArenasToRelease(nullptr),
-#endif
 #endif
     lock(nullptr),
     lockOwner(nullptr),
@@ -1930,15 +1926,9 @@ ArenaLists::allocateFromArenaInner(JS::Zone *zone, ArenaHeader *aheader, AllocKi
 bool
 GCRuntime::shouldCompact()
 {
-#ifdef JSGC_COMPACTING
     return invocationKind == GC_SHRINK && isCompactingGCEnabled();
-#else
-    return false;
-#endif
 }
 
-#ifdef JSGC_COMPACTING
-
 void
 GCRuntime::disableCompactingGC()
 {
@@ -2715,12 +2705,10 @@ GCRuntime::releaseRelocatedArenasWithoutUnlocking(ArenaHeader *relocatedList, co
     }
 }
 
-#endif // JSGC_COMPACTING
-
 void
 GCRuntime::releaseHeldRelocatedArenas()
 {
-#if defined(JSGC_COMPACTING) && defined(DEBUG)
+#ifdef DEBUG
     // In debug mode we don't release relocated arenas straight away.  Instead
     // we protect them and hold onto them until the next GC sweep phase to catch
     // any pointers to them that didn't get forwarded.
@@ -5480,9 +5468,6 @@ GCRuntime::endSweepPhase(bool lastGC)
 bool
 GCRuntime::compactPhase(bool lastGC)
 {
-#ifndef JSGC_COMPACTING
-    MOZ_CRASH();
-#else
     gcstats::AutoPhase ap(stats, gcstats::PHASE_COMPACT);
 
     if (isIncremental) {
@@ -5547,8 +5532,6 @@ GCRuntime::compactPhase(bool lastGC)
         }
     }
 #endif
-
-#endif // JSGC_COMPACTING
     return true;
 }
 
@@ -5708,7 +5691,6 @@ GCRuntime::resetIncrementalGC(const char *reason)
         break;
       }
 
-#ifdef JSGC_COMPACTING
       case COMPACT: {
         {
             gcstats::AutoPhase ap(stats, gcstats::PHASE_WAIT_BACKGROUND_THREAD);
@@ -5724,7 +5706,6 @@ GCRuntime::resetIncrementalGC(const char *reason)
         invocationKind = oldInvocationKind;
         break;
       }
-#endif
 
       default:
         MOZ_CRASH("Invalid incremental GC state");
@@ -6412,7 +6393,7 @@ GCRuntime::onOutOfMallocMemory(const AutoLockGC &lock)
 {
     // Release any relocated arenas we may be holding on to, without releasing
     // the GC lock.
-#if defined(JSGC_COMPACTING) && defined(DEBUG)
+#ifdef DEBUG
     unprotectRelocatedArenas(relocatedArenasToRelease);
     releaseRelocatedArenasWithoutUnlocking(relocatedArenasToRelease, lock);
     relocatedArenasToRelease = nullptr;
@@ -7133,19 +7114,13 @@ JS::IsIncrementalGCEnabled(JSRuntime *rt)
 JS_PUBLIC_API(void)
 JS::DisableCompactingGC(JSRuntime *rt)
 {
-#ifdef JSGC_COMPACTING
     rt->gc.disableCompactingGC();
-#endif
 }
 
 JS_PUBLIC_API(bool)
 JS::IsCompactingGCEnabled(JSRuntime *rt)
 {
-#ifdef JSGC_COMPACTING
     return rt->gc.isCompactingGCEnabled();
-#else
-    return false;
-#endif
 }
 
 JS_PUBLIC_API(bool)

js/src/jsgc.h

@@ -454,11 +454,9 @@ class ArenaList {
         return *this;
     }
 
-#ifdef JSGC_COMPACTING
     ArenaHeader *removeRemainingArenas(ArenaHeader **arenap, const AutoLockGC &lock);
     ArenaHeader *pickArenasToRelocate(JSRuntime *runtime);
     ArenaHeader *relocateArenas(ArenaHeader *toRelocate, ArenaHeader *relocated);
-#endif
 };
 
 /*
@@ -785,9 +783,7 @@ class ArenaLists
         MOZ_ASSERT(freeLists[kind].isEmpty());
     }
 
-#ifdef JSGC_COMPACTING
     ArenaHeader *relocateArenas(ArenaHeader *relocatedList);
-#endif
 
     void queueForegroundObjectsForSweep(FreeOp *fop);
     void queueForegroundThingsForSweep(FreeOp *fop);
@@ -1270,9 +1266,7 @@ inline void
 CheckGCThingAfterMovingGC(T *t)
 {
     MOZ_ASSERT_IF(t, !IsInsideNursery(t));
-#ifdef JSGC_COMPACTING
     MOZ_ASSERT_IF(t, !IsForwarded(t));
-#endif
 }
 
 inline void
@@ -1429,16 +1423,11 @@ struct AutoDisableProxyCheck
 
 struct AutoDisableCompactingGC
 {
-#ifdef JSGC_COMPACTING
     explicit AutoDisableCompactingGC(JSRuntime *rt);
     ~AutoDisableCompactingGC();
 
   private:
     gc::GCRuntime &gc;
-#else
-    explicit AutoDisableCompactingGC(JSRuntime *rt) {}
-    ~AutoDisableCompactingGC() {}
-#endif
 };
 
 void

js/src/jsinfer.cpp

@@ -4891,8 +4891,6 @@ JSCompartment::sweepNewTypeObjectTable(NewTypeObjectTable &table)
     }
 }
 
-#ifdef JSGC_COMPACTING
-
 void
 JSCompartment::fixupNewTypeObjectTable(NewTypeObjectTable &table)
 {
@@ -4966,8 +4964,6 @@ TypeObject::fixupAfterMovingGC()
     }
 }
 
-#endif // JSGC_COMPACTING
-
 #ifdef JSGC_HASH_TABLE_CHECKS
 
 void

js/src/jsinfer.h

@@ -925,10 +925,7 @@ class TypeNewScript
 
     void trace(JSTracer *trc);
     void sweep();
-
-#ifdef JSGC_COMPACTING
     void fixupAfterMovingGC();
-#endif
 
     void registerNewObject(PlainObject *res);
     void unregisterNewObject(PlainObject *res);
@@ -1241,9 +1238,7 @@ struct TypeObject : public gc::TenuredCell
         flags_ |= generation << OBJECT_FLAG_GENERATION_SHIFT;
     }
 
-#ifdef JSGC_COMPACTING
     void fixupAfterMovingGC();
-#endif
 
     size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const;
 

js/src/jspropertytree.cpp

@@ -235,8 +235,6 @@ Shape::finalize(FreeOp *fop)
         fop->delete_(kids.toHash());
 }
 
-#ifdef JSGC_COMPACTING
-
 void
 Shape::fixupDictionaryShapeAfterMovingGC()
 {
@@ -322,8 +320,6 @@ Shape::fixupAfterMovingGC()
         fixupShapeTreeAfterMovingGC();
 }
 
-#endif // JSGC_COMPACTING
-
 void
 ShapeGetterSetterRef::mark(JSTracer *trc)
 {

js/src/jspubtd.h

@@ -20,8 +20,7 @@
 
 #include "js/TypeDecls.h"
 
-#if (defined(JS_GC_ZEAL)) || \
-    (defined(JSGC_COMPACTING) && defined(DEBUG))
+#if (defined(JS_GC_ZEAL)) || defined(DEBUG)
 # define JSGC_HASH_TABLE_CHECKS
 #endif
 

js/src/vm/Shape-inl.h

@@ -224,14 +224,12 @@ GetShapeAttributes(JSObject *obj, Shape *shape)
     return shape->attributes();
 }
 
-#ifdef JSGC_COMPACTING
 inline void
 BaseShape::fixupAfterMovingGC()
 {
     if (hasTable())
         table().fixupAfterMovingGC();
 }
-#endif
 
 } /* namespace js */
 

js/src/vm/Shape.cpp

@@ -256,7 +256,6 @@ ShapeTable::search(jsid id, bool adding)
     MOZ_CRASH("Shape::search failed to find an expected entry.");
 }
 
-#ifdef JSGC_COMPACTING
 void
 ShapeTable::fixupAfterMovingGC()
 {
@@ -268,7 +267,6 @@ ShapeTable::fixupAfterMovingGC()
             entry.setPreservingCollision(Forwarded(shape));
     }
 }
-#endif
 
 bool
 ShapeTable::change(int log2Delta, ExclusiveContext *cx)
@@ -1693,7 +1691,6 @@ JSCompartment::sweepInitialShapeTable()
     }
 }
 
-#ifdef JSGC_COMPACTING
 void
 JSCompartment::fixupInitialShapeTable()
 {
@@ -1732,7 +1729,6 @@ JSCompartment::fixupInitialShapeTable()
         }
     }
 }
-#endif // JSGC_COMPACTING
 
 void
 AutoRooterGetterSetter::Inner::trace(JSTracer *trc)

js/src/vm/Shape.h

@@ -227,10 +227,8 @@ class ShapeTable {
     bool change(int log2Delta, ExclusiveContext *cx);
     Entry &search(jsid id, bool adding);
 
-#ifdef JSGC_COMPACTING
     /* Update entries whose shapes have been moved */
     void fixupAfterMovingGC();
-#endif
 
   private:
     Entry &getEntry(uint32_t i) const {
@@ -530,9 +528,7 @@ class BaseShape : public gc::TenuredCell
             gc::MarkObject(trc, &metadata, "metadata");
     }
 
-#ifdef JSGC_COMPACTING
     void fixupAfterMovingGC();
-#endif
 
   private:
     static void staticAsserts() {
@@ -1061,9 +1057,7 @@ class Shape : public gc::TenuredCell
     inline Shape *search(ExclusiveContext *cx, jsid id);
     inline Shape *searchLinear(jsid id);
 
-#ifdef JSGC_COMPACTING
     void fixupAfterMovingGC();
-#endif
 
     /* For JIT usage */
     static inline size_t offsetOfBase() { return offsetof(Shape, base_); }
@@ -1071,10 +1065,8 @@ class Shape : public gc::TenuredCell
     static inline uint32_t fixedSlotsMask() { return FIXED_SLOTS_MASK; }
 
   private:
-#ifdef JSGC_COMPACTING
     void fixupDictionaryShapeAfterMovingGC();
     void fixupShapeTreeAfterMovingGC();
-#endif
 
     static void staticAsserts() {
         JS_STATIC_ASSERT(offsetof(Shape, base_) == offsetof(js::shadow::Shape, base));