michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * vim: set ts=8 sts=4 et sw=4 tw=99:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "gc/Zone.h"
michael@0: 
michael@0: #include "jsgc.h"
michael@0: 
michael@0: #ifdef JS_ION
michael@0: #include "jit/BaselineJIT.h"
michael@0: #include "jit/Ion.h"
michael@0: #include "jit/JitCompartment.h"
michael@0: #endif
michael@0: #include "vm/Debugger.h"
michael@0: #include "vm/Runtime.h"
michael@0: 
michael@0: #include "jsgcinlines.h"
michael@0: 
michael@0: using namespace js;
michael@0: using namespace js::gc;
michael@0: 
michael@0: JS::Zone::Zone(JSRuntime *rt)
michael@0:   : JS::shadow::Zone(rt, &rt->gcMarker),
michael@0:     allocator(this),
michael@0:     ionUsingBarriers_(false),
michael@0:     active(false),
michael@0:     gcScheduled(false),
michael@0:     gcState(NoGC),
michael@0:     gcPreserveCode(false),
michael@0:     gcBytes(0),
michael@0:     gcTriggerBytes(0),
michael@0:     gcHeapGrowthFactor(3.0),
michael@0:     isSystem(false),
michael@0:     usedByExclusiveThread(false),
michael@0:     scheduledForDestruction(false),
michael@0:     maybeAlive(true),
michael@0:     gcMallocBytes(0),
michael@0:     gcMallocGCTriggered(false),
michael@0:     gcGrayRoots(),
michael@0:     data(nullptr),
michael@0:     types(this)
michael@0: #ifdef JS_ION
michael@0:     , jitZone_(nullptr)
michael@0: #endif
michael@0: {
michael@0:     /* Ensure that there are no vtables to mess us up here. */
michael@0:     JS_ASSERT(reinterpret_cast<JS::shadow::Zone *>(this) ==
michael@0:               static_cast<JS::shadow::Zone *>(this));
michael@0: 
michael@0:     setGCMaxMallocBytes(rt->gcMaxMallocBytes * 0.9);
michael@0: }
michael@0: 
michael@0: Zone::~Zone()
michael@0: {
michael@0:     if (this == runtimeFromMainThread()->systemZone)
michael@0:         runtimeFromMainThread()->systemZone = nullptr;
michael@0: 
michael@0: #ifdef JS_ION
michael@0:     js_delete(jitZone_);
michael@0: #endif
michael@0: }
michael@0: 
michael@0: void
michael@0: Zone::setNeedsBarrier(bool needs, ShouldUpdateIon updateIon)
michael@0: {
michael@0: #ifdef JS_ION
michael@0:     if (updateIon == UpdateIon && needs != ionUsingBarriers_) {
michael@0:         jit::ToggleBarriers(this, needs);
michael@0:         ionUsingBarriers_ = needs;
michael@0:     }
michael@0: #endif
michael@0: 
michael@0:     if (needs && runtimeFromMainThread()->isAtomsZone(this))
michael@0:         JS_ASSERT(!runtimeFromMainThread()->exclusiveThreadsPresent());
michael@0: 
michael@0:     JS_ASSERT_IF(needs, canCollect());
michael@0:     needsBarrier_ = needs;
michael@0: }
michael@0: 
michael@0: void
michael@0: Zone::resetGCMallocBytes()
michael@0: {
michael@0:     gcMallocBytes = ptrdiff_t(gcMaxMallocBytes);
michael@0:     gcMallocGCTriggered = false;
michael@0: }
michael@0: 
michael@0: void
michael@0: Zone::setGCMaxMallocBytes(size_t value)
michael@0: {
michael@0:     /*
michael@0:      * For compatibility treat any value that exceeds PTRDIFF_T_MAX to
michael@0:      * mean that value.
michael@0:      */
michael@0:     gcMaxMallocBytes = (ptrdiff_t(value) >= 0) ? value : size_t(-1) >> 1;
michael@0:     resetGCMallocBytes();
michael@0: }
michael@0: 
michael@0: void
michael@0: Zone::onTooMuchMalloc()
michael@0: {
michael@0:     if (!gcMallocGCTriggered)
michael@0:         gcMallocGCTriggered = TriggerZoneGC(this, JS::gcreason::TOO_MUCH_MALLOC);
michael@0: }
michael@0: 
michael@0: void
michael@0: Zone::sweep(FreeOp *fop, bool releaseTypes, bool *oom)
michael@0: {
michael@0:     /*
michael@0:      * Periodically release observed types for all scripts. This is safe to
michael@0:      * do when there are no frames for the zone on the stack.
michael@0:      */
michael@0:     if (active)
michael@0:         releaseTypes = false;
michael@0: 
michael@0:     {
michael@0:         gcstats::AutoPhase ap(fop->runtime()->gcStats, gcstats::PHASE_DISCARD_ANALYSIS);
michael@0:         types.sweep(fop, releaseTypes, oom);
michael@0:     }
michael@0: 
michael@0:     if (!fop->runtime()->debuggerList.isEmpty())
michael@0:         sweepBreakpoints(fop);
michael@0: 
michael@0:     active = false;
michael@0: }
michael@0: 
michael@0: void
michael@0: Zone::sweepBreakpoints(FreeOp *fop)
michael@0: {
michael@0:     /*
michael@0:      * Sweep all compartments in a zone at the same time, since there is no way
michael@0:      * to iterate over the scripts belonging to a single compartment in a zone.
michael@0:      */
michael@0: 
michael@0:     gcstats::AutoPhase ap1(fop->runtime()->gcStats, gcstats::PHASE_SWEEP_TABLES);
michael@0:     gcstats::AutoPhase ap2(fop->runtime()->gcStats, gcstats::PHASE_SWEEP_TABLES_BREAKPOINT);
michael@0: 
michael@0:     JS_ASSERT(isGCSweeping());
michael@0:     for (CellIterUnderGC i(this, FINALIZE_SCRIPT); !i.done(); i.next()) {
michael@0:         JSScript *script = i.get<JSScript>();
michael@0:         JS_ASSERT(script->zone()->isGCSweeping());
michael@0:         if (!script->hasAnyBreakpointsOrStepMode())
michael@0:             continue;
michael@0: 
michael@0:         bool scriptGone = IsScriptAboutToBeFinalized(&script);
michael@0:         JS_ASSERT(script == i.get<JSScript>());
michael@0:         for (unsigned i = 0; i < script->length(); i++) {
michael@0:             BreakpointSite *site = script->getBreakpointSite(script->offsetToPC(i));
michael@0:             if (!site)
michael@0:                 continue;
michael@0: 
michael@0:             Breakpoint *nextbp;
michael@0:             for (Breakpoint *bp = site->firstBreakpoint(); bp; bp = nextbp) {
michael@0:                 nextbp = bp->nextInSite();
michael@0:                 HeapPtrObject& dbgobj = bp->debugger->toJSObjectRef();
michael@0:                 JS_ASSERT(dbgobj->zone()->isGCSweeping());
michael@0:                 bool dying = scriptGone || IsObjectAboutToBeFinalized(&dbgobj);
michael@0:                 JS_ASSERT_IF(!dying, bp->getHandler()->isMarked());
michael@0:                 if (dying)
michael@0:                     bp->destroy(fop);
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: void
michael@0: Zone::discardJitCode(FreeOp *fop)
michael@0: {
michael@0: #ifdef JS_ION
michael@0:     if (!jitZone())
michael@0:         return;
michael@0: 
michael@0:     if (isPreservingCode()) {
michael@0:         PurgeJITCaches(this);
michael@0:     } else {
michael@0: 
michael@0: # ifdef DEBUG
michael@0:         /* Assert no baseline scripts are marked as active. */
michael@0:         for (CellIterUnderGC i(this, FINALIZE_SCRIPT); !i.done(); i.next()) {
michael@0:             JSScript *script = i.get<JSScript>();
michael@0:             JS_ASSERT_IF(script->hasBaselineScript(), !script->baselineScript()->active());
michael@0:         }
michael@0: # endif
michael@0: 
michael@0:         /* Mark baseline scripts on the stack as active. */
michael@0:         jit::MarkActiveBaselineScripts(this);
michael@0: 
michael@0:         /* Only mark OSI points if code is being discarded. */
michael@0:         jit::InvalidateAll(fop, this);
michael@0: 
michael@0:         for (CellIterUnderGC i(this, FINALIZE_SCRIPT); !i.done(); i.next()) {
michael@0:             JSScript *script = i.get<JSScript>();
michael@0:             jit::FinishInvalidation<SequentialExecution>(fop, script);
michael@0: 
michael@0:             // Preserve JIT code that have been recently used in
michael@0:             // parallel. Note that we mark their baseline scripts as active as
michael@0:             // well to preserve them.
michael@0:             if (script->hasParallelIonScript()) {
michael@0:                 if (jit::ShouldPreserveParallelJITCode(runtimeFromMainThread(), script)) {
michael@0:                     script->parallelIonScript()->purgeCaches();
michael@0:                     script->baselineScript()->setActive();
michael@0:                 } else {
michael@0:                     jit::FinishInvalidation<ParallelExecution>(fop, script);
michael@0:                 }
michael@0:             }
michael@0: 
michael@0:             /*
michael@0:              * Discard baseline script if it's not marked as active. Note that
michael@0:              * this also resets the active flag.
michael@0:              */
michael@0:             jit::FinishDiscardBaselineScript(fop, script);
michael@0: 
michael@0:             /*
michael@0:              * Use counts for scripts are reset on GC. After discarding code we
michael@0:              * need to let it warm back up to get information such as which
michael@0:              * opcodes are setting array holes or accessing getter properties.
michael@0:              */
michael@0:             script->resetUseCount();
michael@0:         }
michael@0: 
michael@0:         jitZone()->optimizedStubSpace()->free();
michael@0:     }
michael@0: #endif
michael@0: }
michael@0: 
michael@0: uint64_t
michael@0: Zone::gcNumber()
michael@0: {
michael@0:     // Zones in use by exclusive threads are not collected, and threads using
michael@0:     // them cannot access the main runtime's gcNumber without racing.
michael@0:     return usedByExclusiveThread ? 0 : runtimeFromMainThread()->gcNumber;
michael@0: }
michael@0: 
michael@0: #ifdef JS_ION
michael@0: js::jit::JitZone *
michael@0: Zone::createJitZone(JSContext *cx)
michael@0: {
michael@0:     MOZ_ASSERT(!jitZone_);
michael@0: 
michael@0:     if (!cx->runtime()->getJitRuntime(cx))
michael@0:         return nullptr;
michael@0: 
michael@0:     jitZone_ = cx->new_<js::jit::JitZone>();
michael@0:     return jitZone_;
michael@0: }
michael@0: #endif
michael@0: 
michael@0: JS::Zone *
michael@0: js::ZoneOfObject(const JSObject &obj)
michael@0: {
michael@0:     return obj.zone();
michael@0: }
michael@0: 
michael@0: JS::Zone *
michael@0: js::ZoneOfObjectFromAnyThread(const JSObject &obj)
michael@0: {
michael@0:     return obj.zoneFromAnyThread();
michael@0: }
michael@0: 
michael@0: bool
michael@0: Zone::hasMarkedCompartments()
michael@0: {
michael@0:     for (CompartmentsInZoneIter comp(this); !comp.done(); comp.next()) {
michael@0:         if (comp->marked)
michael@0:             return true;
michael@0:     }
michael@0:     return false;
michael@0: }