The Tor Browser: js/src/jsworkers.cpp@6474c204b198 (annotated)

js/src/jsworkers.cpp@6474c204b198 (annotated)

js/src/jsworkers.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- 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 "jsworkers.h"
 #ifdef JS_THREADSAFE
 #include "mozilla/DebugOnly.h"
 #include "jsnativestack.h"
 #include "prmjtime.h"
 #include "frontend/BytecodeCompiler.h"
 #include "jit/IonBuilder.h"
 #include "vm/Debugger.h"
 #include "vm/TraceLogging.h"
 #include "jscntxtinlines.h"
 #include "jscompartmentinlines.h"
 #include "jsobjinlines.h"
 #include "jsscriptinlines.h"
 using namespace js;
 using mozilla::ArrayLength;
 using mozilla::DebugOnly;
 namespace js {
 GlobalWorkerThreadState gWorkerThreadState;
 } // namespace js
 void
 js::EnsureWorkerThreadsInitialized(ExclusiveContext *cx)
 {
     // If 'cx' is not a JSContext, we are already off the main thread and the
     // worker threads would have already been initialized.
     if (!cx->isJSContext())
         return;
     WorkerThreadState().ensureInitialized();
 }
 static size_t
 ThreadCountForCPUCount(size_t cpuCount)
 {
     return Max(cpuCount, (size_t)2);
 }
 void
 js::SetFakeCPUCount(size_t count)
 {
     // This must be called before the threads have been initialized.
     JS_ASSERT(!WorkerThreadState().threads);
     WorkerThreadState().cpuCount = count;
     WorkerThreadState().threadCount = ThreadCountForCPUCount(count);
 }
 #ifdef JS_ION
 bool
 js::StartOffThreadAsmJSCompile(ExclusiveContext *cx, AsmJSParallelTask *asmData)
 {
     // Threads already initialized by the AsmJS compiler.
     JS_ASSERT(asmData->mir);
     JS_ASSERT(asmData->lir == nullptr);
     AutoLockWorkerThreadState lock;
     // Don't append this task if another failed.
     if (WorkerThreadState().asmJSWorkerFailed())
         return false;
     if (!WorkerThreadState().asmJSWorklist().append(asmData))
         return false;
     WorkerThreadState().notifyOne(GlobalWorkerThreadState::PRODUCER);
     return true;
 }
 bool
 js::StartOffThreadIonCompile(JSContext *cx, jit::IonBuilder *builder)
 {
     EnsureWorkerThreadsInitialized(cx);
     AutoLockWorkerThreadState lock;
     if (!WorkerThreadState().ionWorklist().append(builder))
         return false;
     WorkerThreadState().notifyOne(GlobalWorkerThreadState::PRODUCER);
     return true;
 }
 /*
  * Move an IonBuilder for which compilation has either finished, failed, or
  * been cancelled into the global finished compilation list. All off thread
  * compilations which are started must eventually be finished.
  */
 static void
 FinishOffThreadIonCompile(jit::IonBuilder *builder)
 {
     WorkerThreadState().ionFinishedList().append(builder);
 }
 #endif // JS_ION
 static inline bool
 CompiledScriptMatches(JSCompartment *compartment, JSScript *script, JSScript *target)
 {
     if (script)
         return target == script;
     return target->compartment() == compartment;
 }
 void
 js::CancelOffThreadIonCompile(JSCompartment *compartment, JSScript *script)
 {
 #ifdef JS_ION
     jit::JitCompartment *jitComp = compartment->jitCompartment();
     if (!jitComp)
         return;
     AutoLockWorkerThreadState lock;
     if (!WorkerThreadState().threads)
         return;
     /* Cancel any pending entries for which processing hasn't started. */
     GlobalWorkerThreadState::IonBuilderVector &worklist = WorkerThreadState().ionWorklist();
     for (size_t i = 0; i < worklist.length(); i++) {
         jit::IonBuilder *builder = worklist[i];
         if (CompiledScriptMatches(compartment, script, builder->script())) {
             FinishOffThreadIonCompile(builder);
             WorkerThreadState().remove(worklist, &i);
         }
     }
     /* Wait for in progress entries to finish up. */
     for (size_t i = 0; i < WorkerThreadState().threadCount; i++) {
         const WorkerThread &helper = WorkerThreadState().threads[i];
         while (helper.ionBuilder &&
                CompiledScriptMatches(compartment, script, helper.ionBuilder->script()))
         {
             helper.ionBuilder->cancel();
             WorkerThreadState().wait(GlobalWorkerThreadState::CONSUMER);
         }
     }
     /* Cancel code generation for any completed entries. */
     GlobalWorkerThreadState::IonBuilderVector &finished = WorkerThreadState().ionFinishedList();
     for (size_t i = 0; i < finished.length(); i++) {
         jit::IonBuilder *builder = finished[i];
         if (CompiledScriptMatches(compartment, script, builder->script())) {
             jit::FinishOffThreadBuilder(builder);
             WorkerThreadState().remove(finished, &i);
         }
     }
 #endif // JS_ION
 }
 static const JSClass workerGlobalClass = {
     "internal-worker-global", JSCLASS_GLOBAL_FLAGS,
     JS_PropertyStub,  JS_DeletePropertyStub,
     JS_PropertyStub,  JS_StrictPropertyStub,
     JS_EnumerateStub, JS_ResolveStub,
     JS_ConvertStub,   nullptr,
     nullptr, nullptr, nullptr,
     JS_GlobalObjectTraceHook
 };
 ParseTask::ParseTask(ExclusiveContext *cx, JSObject *exclusiveContextGlobal, JSContext *initCx,
                      const jschar *chars, size_t length,
                      JS::OffThreadCompileCallback callback, void *callbackData)
   : cx(cx), options(initCx), chars(chars), length(length),
     alloc(JSRuntime::TEMP_LIFO_ALLOC_PRIMARY_CHUNK_SIZE),
     exclusiveContextGlobal(initCx, exclusiveContextGlobal), optionsElement(initCx),
     optionsIntroductionScript(initCx), callback(callback), callbackData(callbackData),
     script(nullptr), errors(cx), overRecursed(false)
 {
 }
 bool
 ParseTask::init(JSContext *cx, const ReadOnlyCompileOptions &options)
 {
     if (!this->options.copy(cx, options))
         return false;
     // Save those compilation options that the ScriptSourceObject can't
     // point at while it's in the compilation's temporary compartment.
     optionsElement = this->options.element();
     this->options.setElement(nullptr);
     optionsIntroductionScript = this->options.introductionScript();
     this->options.setIntroductionScript(nullptr);
     return true;
 }
 void
 ParseTask::activate(JSRuntime *rt)
 {
     rt->setUsedByExclusiveThread(exclusiveContextGlobal->zone());
     cx->enterCompartment(exclusiveContextGlobal->compartment());
 }
 void
 ParseTask::finish()
 {
     if (script) {
         // Initialize the ScriptSourceObject slots that we couldn't while the SSO
         // was in the temporary compartment.
         ScriptSourceObject &sso = script->sourceObject()->as<ScriptSourceObject>();
         sso.initElement(optionsElement);
         sso.initIntroductionScript(optionsIntroductionScript);
     }
 }
 ParseTask::~ParseTask()
 {
     // ParseTask takes over ownership of its input exclusive context.
     js_delete(cx);
     for (size_t i = 0; i < errors.length(); i++)
         js_delete(errors[i]);
 }
 void
 js::CancelOffThreadParses(JSRuntime *rt)
 {
     AutoLockWorkerThreadState lock;
     if (!WorkerThreadState().threads)
         return;
     // Instead of forcibly canceling pending parse tasks, just wait for all scheduled
     // and in progress ones to complete. Otherwise the final GC may not collect
     // everything due to zones being used off thread.
     while (true) {
         bool pending = false;
         GlobalWorkerThreadState::ParseTaskVector &worklist = WorkerThreadState().parseWorklist();
         for (size_t i = 0; i < worklist.length(); i++) {
             ParseTask *task = worklist[i];
             if (task->runtimeMatches(rt))
                 pending = true;
         }
         if (!pending) {
             bool inProgress = false;
             for (size_t i = 0; i < WorkerThreadState().threadCount; i++) {
                 ParseTask *task = WorkerThreadState().threads[i].parseTask;
                 if (task && task->runtimeMatches(rt))
                     inProgress = true;
             }
             if (!inProgress)
                 break;
         }
         WorkerThreadState().wait(GlobalWorkerThreadState::CONSUMER);
     }
     // Clean up any parse tasks which haven't been finished by the main thread.
     GlobalWorkerThreadState::ParseTaskVector &finished = WorkerThreadState().parseFinishedList();
     while (true) {
         bool found = false;
         for (size_t i = 0; i < finished.length(); i++) {
             ParseTask *task = finished[i];
             if (task->runtimeMatches(rt)) {
                 found = true;
                 AutoUnlockWorkerThreadState unlock;
                 WorkerThreadState().finishParseTask(/* maybecx = */ nullptr, rt, task);
             }
         }
         if (!found)
             break;
     }
 }
 bool
 js::OffThreadParsingMustWaitForGC(JSRuntime *rt)
 {
     // Off thread parsing can't occur during incremental collections on the
     // atoms compartment, to avoid triggering barriers. (Outside the atoms
     // compartment, the compilation will use a new zone that is never
     // collected.) If an atoms-zone GC is in progress, hold off on executing the
     // parse task until the atoms-zone GC completes (see
     // EnqueuePendingParseTasksAfterGC).
     return rt->activeGCInAtomsZone();
 }
 bool
 js::StartOffThreadParseScript(JSContext *cx, const ReadOnlyCompileOptions &options,
                               const jschar *chars, size_t length,
                               JS::OffThreadCompileCallback callback, void *callbackData)
 {
     // Suppress GC so that calls below do not trigger a new incremental GC
     // which could require barriers on the atoms compartment.
     gc::AutoSuppressGC suppress(cx);
     SourceBufferHolder srcBuf(chars, length, SourceBufferHolder::NoOwnership);
     frontend::MaybeCallSourceHandler(cx, options, srcBuf);
     EnsureWorkerThreadsInitialized(cx);
     JS::CompartmentOptions compartmentOptions(cx->compartment()->options());
     compartmentOptions.setZone(JS::FreshZone);
     compartmentOptions.setInvisibleToDebugger(true);
     compartmentOptions.setMergeable(true);
     // Don't falsely inherit the host's global trace hook.
     compartmentOptions.setTrace(nullptr);
     JSObject *global = JS_NewGlobalObject(cx, &workerGlobalClass, nullptr,
                                           JS::FireOnNewGlobalHook, compartmentOptions);
     if (!global)
         return false;
     JS_SetCompartmentPrincipals(global->compartment(), cx->compartment()->principals);
     RootedObject obj(cx);
     // Initialize all classes needed for parsing while we are still on the main
     // thread. Do this for both the target and the new global so that prototype
     // pointers can be changed infallibly after parsing finishes.
     if (!GetBuiltinConstructor(cx, JSProto_Function, &obj) ||
         !GetBuiltinConstructor(cx, JSProto_Array, &obj) ||
         !GetBuiltinConstructor(cx, JSProto_RegExp, &obj) ||
         !GetBuiltinConstructor(cx, JSProto_Iterator, &obj))
     {
         return false;
     }
     {
         AutoCompartment ac(cx, global);
         if (!GetBuiltinConstructor(cx, JSProto_Function, &obj) ||
             !GetBuiltinConstructor(cx, JSProto_Array, &obj) ||
             !GetBuiltinConstructor(cx, JSProto_RegExp, &obj) ||
             !GetBuiltinConstructor(cx, JSProto_Iterator, &obj))
         {
             return false;
         }
     }
     ScopedJSDeletePtr<ExclusiveContext> workercx(
         cx->new_<ExclusiveContext>(cx->runtime(), (PerThreadData *) nullptr,
                                    ThreadSafeContext::Context_Exclusive));
     if (!workercx)
         return false;
     ScopedJSDeletePtr<ParseTask> task(
         cx->new_<ParseTask>(workercx.get(), global, cx, chars, length,
                             callback, callbackData));
     if (!task)
         return false;
     workercx.forget();
     if (!task->init(cx, options))
         return false;
     if (OffThreadParsingMustWaitForGC(cx->runtime())) {
         AutoLockWorkerThreadState lock;
         if (!WorkerThreadState().parseWaitingOnGC().append(task.get()))
             return false;
     } else {
         task->activate(cx->runtime());
         AutoLockWorkerThreadState lock;
         if (!WorkerThreadState().parseWorklist().append(task.get()))
             return false;
         WorkerThreadState().notifyOne(GlobalWorkerThreadState::PRODUCER);
     }
     task.forget();
     return true;
 }
 void
 js::EnqueuePendingParseTasksAfterGC(JSRuntime *rt)
 {
     JS_ASSERT(!OffThreadParsingMustWaitForGC(rt));
     GlobalWorkerThreadState::ParseTaskVector newTasks;
     {
         AutoLockWorkerThreadState lock;
         GlobalWorkerThreadState::ParseTaskVector &waiting = WorkerThreadState().parseWaitingOnGC();
         for (size_t i = 0; i < waiting.length(); i++) {
             ParseTask *task = waiting[i];
             if (task->runtimeMatches(rt)) {
                 newTasks.append(task);
                 WorkerThreadState().remove(waiting, &i);
             }
         }
     }
     if (newTasks.empty())
         return;
     // This logic should mirror the contents of the !activeGCInAtomsZone()
     // branch in StartOffThreadParseScript:
     for (size_t i = 0; i < newTasks.length(); i++)
         newTasks[i]->activate(rt);
     AutoLockWorkerThreadState lock;
     for (size_t i = 0; i < newTasks.length(); i++)
         WorkerThreadState().parseWorklist().append(newTasks[i]);
     WorkerThreadState().notifyAll(GlobalWorkerThreadState::PRODUCER);
 }
 static const uint32_t WORKER_STACK_SIZE = 512 * 1024;
 static const uint32_t WORKER_STACK_QUOTA = 450 * 1024;
 void
 GlobalWorkerThreadState::ensureInitialized()
 {
     JS_ASSERT(this == &WorkerThreadState());
     AutoLockWorkerThreadState lock;
     if (threads)
         return;
     threads = js_pod_calloc<WorkerThread>(threadCount);
     if (!threads)
         CrashAtUnhandlableOOM("GlobalWorkerThreadState::ensureInitialized");
     for (size_t i = 0; i < threadCount; i++) {
         WorkerThread &helper = threads[i];
         helper.threadData.construct(static_cast<JSRuntime *>(nullptr));
         helper.thread = PR_CreateThread(PR_USER_THREAD,
                                         WorkerThread::ThreadMain, &helper,
                                         PR_PRIORITY_NORMAL, PR_GLOBAL_THREAD, PR_JOINABLE_THREAD, WORKER_STACK_SIZE);
         if (!helper.thread || !helper.threadData.ref().init())
             CrashAtUnhandlableOOM("GlobalWorkerThreadState::ensureInitialized");
     }
     resetAsmJSFailureState();
 }
 GlobalWorkerThreadState::GlobalWorkerThreadState()
 {
     mozilla::PodZero(this);
     cpuCount = GetCPUCount();
     threadCount = ThreadCountForCPUCount(cpuCount);
     MOZ_ASSERT(cpuCount > 0, "GetCPUCount() seems broken");
     workerLock = PR_NewLock();
     consumerWakeup = PR_NewCondVar(workerLock);
     producerWakeup = PR_NewCondVar(workerLock);
 }
 void
 GlobalWorkerThreadState::finish()
 {
     if (threads) {
         for (size_t i = 0; i < threadCount; i++)
             threads[i].destroy();
         js_free(threads);
     }
     PR_DestroyCondVar(consumerWakeup);
     PR_DestroyCondVar(producerWakeup);
     PR_DestroyLock(workerLock);
 }
 void
 GlobalWorkerThreadState::lock()
 {
     JS_ASSERT(!isLocked());
     AssertCurrentThreadCanLock(WorkerThreadStateLock);
     PR_Lock(workerLock);
 #ifdef DEBUG
     lockOwner = PR_GetCurrentThread();
 #endif
 }
 void
 GlobalWorkerThreadState::unlock()
 {
     JS_ASSERT(isLocked());
 #ifdef DEBUG
     lockOwner = nullptr;
 #endif
     PR_Unlock(workerLock);
 }
 #ifdef DEBUG
 bool
 GlobalWorkerThreadState::isLocked()
 {
     return lockOwner == PR_GetCurrentThread();
 }
 #endif
 void
 GlobalWorkerThreadState::wait(CondVar which, uint32_t millis)
 {
     JS_ASSERT(isLocked());
 #ifdef DEBUG
     lockOwner = nullptr;
 #endif
     DebugOnly<PRStatus> status =
         PR_WaitCondVar((which == CONSUMER) ? consumerWakeup : producerWakeup,
                        millis ? PR_MillisecondsToInterval(millis) : PR_INTERVAL_NO_TIMEOUT);
     JS_ASSERT(status == PR_SUCCESS);
 #ifdef DEBUG
     lockOwner = PR_GetCurrentThread();
 #endif
 }
 void
 GlobalWorkerThreadState::notifyAll(CondVar which)
 {
     JS_ASSERT(isLocked());
     PR_NotifyAllCondVar((which == CONSUMER) ? consumerWakeup : producerWakeup);
 }
 void
 GlobalWorkerThreadState::notifyOne(CondVar which)
 {
     JS_ASSERT(isLocked());
     PR_NotifyCondVar((which == CONSUMER) ? consumerWakeup : producerWakeup);
 }
 bool
 GlobalWorkerThreadState::canStartAsmJSCompile()
 {
     // Don't execute an AsmJS job if an earlier one failed.
     JS_ASSERT(isLocked());
     return !asmJSWorklist().empty() && !numAsmJSFailedJobs;
 }
 bool
 GlobalWorkerThreadState::canStartIonCompile()
 {
     // A worker thread can begin an Ion compilation if (a) there is some script
     // which is waiting to be compiled, and (b) no other worker thread is
     // currently compiling a script. The latter condition ensures that two
     // compilations cannot simultaneously occur.
     if (ionWorklist().empty())
         return false;
     for (size_t i = 0; i < threadCount; i++) {
         if (threads[i].ionBuilder)
             return false;
     }
     return true;
 }
 bool
 GlobalWorkerThreadState::canStartParseTask()
 {
     // Don't allow simultaneous off thread parses, to reduce contention on the
     // atoms table. Note that asm.js compilation depends on this to avoid
     // stalling the worker thread, as off thread parse tasks can trigger and
     // block on other off thread asm.js compilation tasks.
     JS_ASSERT(isLocked());
     if (parseWorklist().empty())
         return false;
     for (size_t i = 0; i < threadCount; i++) {
         if (threads[i].parseTask)
             return false;
     }
     return true;
 }
 bool
 GlobalWorkerThreadState::canStartCompressionTask()
 {
     return !compressionWorklist().empty();
 }
 static void
 CallNewScriptHookForAllScripts(JSContext *cx, HandleScript script)
 {
     // We should never hit this, since nested scripts are also constructed via
     // BytecodeEmitter instances on the stack.
     JS_CHECK_RECURSION(cx, return);
     // Recurse to any nested scripts.
     if (script->hasObjects()) {
         ObjectArray *objects = script->objects();
         for (size_t i = 0; i < objects->length; i++) {
             JSObject *obj = objects->vector[i];
             if (obj->is<JSFunction>()) {
                 JSFunction *fun = &obj->as<JSFunction>();
                 if (fun->hasScript()) {
                     RootedScript nested(cx, fun->nonLazyScript());
                     CallNewScriptHookForAllScripts(cx, nested);
                 }
             }
         }
     }
     // The global new script hook is called on every script that was compiled.
     RootedFunction function(cx, script->functionNonDelazifying());
     CallNewScriptHook(cx, script, function);
 }
 static void
 LeaveParseTaskZone(JSRuntime *rt, ParseTask *task)
 {
     // Mark the zone as no longer in use by an ExclusiveContext, and available
     // to be collected by the GC.
     rt->clearUsedByExclusiveThread(task->cx->zone());
 }
 JSScript *
 GlobalWorkerThreadState::finishParseTask(JSContext *maybecx, JSRuntime *rt, void *token)
 {
     ScopedJSDeletePtr<ParseTask> parseTask;
     // The token is a ParseTask* which should be in the finished list.
     // Find and remove its entry.
     {
         AutoLockWorkerThreadState lock;
         ParseTaskVector &finished = parseFinishedList();
         for (size_t i = 0; i < finished.length(); i++) {
             if (finished[i] == token) {
                 parseTask = finished[i];
                 remove(finished, &i);
                 break;
             }
         }
     }
     JS_ASSERT(parseTask);
     if (!maybecx) {
         LeaveParseTaskZone(rt, parseTask);
         return nullptr;
     }
     JSContext *cx = maybecx;
     JS_ASSERT(cx->compartment());
     // Make sure we have all the constructors we need for the prototype
     // remapping below, since we can't GC while that's happening.
     Rooted<GlobalObject*> global(cx, &cx->global()->as<GlobalObject>());
     if (!GlobalObject::ensureConstructor(cx, global, JSProto_Object) ||
         !GlobalObject::ensureConstructor(cx, global, JSProto_Array) ||
         !GlobalObject::ensureConstructor(cx, global, JSProto_Function) ||
         !GlobalObject::ensureConstructor(cx, global, JSProto_RegExp) ||
         !GlobalObject::ensureConstructor(cx, global, JSProto_Iterator))
     {
         LeaveParseTaskZone(rt, parseTask);
         return nullptr;
     }
     LeaveParseTaskZone(rt, parseTask);
     // Point the prototypes of any objects in the script's compartment to refer
     // to the corresponding prototype in the new compartment. This will briefly
     // create cross compartment pointers, which will be fixed by the
     // MergeCompartments call below.
     for (gc::CellIter iter(parseTask->cx->zone(), gc::FINALIZE_TYPE_OBJECT);
          !iter.done();
          iter.next())
     {
         types::TypeObject *object = iter.get<types::TypeObject>();
         TaggedProto proto(object->proto());
         if (!proto.isObject())
             continue;
         JSProtoKey key = JS::IdentifyStandardPrototype(proto.toObject());
         if (key == JSProto_Null)
             continue;
         JS_ASSERT(key == JSProto_Object || key == JSProto_Array ||
                   key == JSProto_Function || key == JSProto_RegExp ||
                   key == JSProto_Iterator);
         JSObject *newProto = GetBuiltinPrototypePure(global, key);
         JS_ASSERT(newProto);
         object->setProtoUnchecked(newProto);
     }
     // Move the parsed script and all its contents into the desired compartment.
     gc::MergeCompartments(parseTask->cx->compartment(), cx->compartment());
     parseTask->finish();
     RootedScript script(rt, parseTask->script);
     assertSameCompartment(cx, script);
     // Report any error or warnings generated during the parse, and inform the
     // debugger about the compiled scripts.
     for (size_t i = 0; i < parseTask->errors.length(); i++)
         parseTask->errors[i]->throwError(cx);
     if (parseTask->overRecursed)
         js_ReportOverRecursed(cx);
     if (script) {
         // The Debugger only needs to be told about the topmost script that was compiled.
         GlobalObject *compileAndGoGlobal = nullptr;
         if (script->compileAndGo())
             compileAndGoGlobal = &script->global();
         Debugger::onNewScript(cx, script, compileAndGoGlobal);
         // The NewScript hook needs to be called for all compiled scripts.
         CallNewScriptHookForAllScripts(cx, script);
     }
     return script;
 }
 void
 WorkerThread::destroy()
 {
     if (thread) {
         {
             AutoLockWorkerThreadState lock;
             terminate = true;
             /* Notify all workers, to ensure that this thread wakes up. */
             WorkerThreadState().notifyAll(GlobalWorkerThreadState::PRODUCER);
         }
         PR_JoinThread(thread);
     }
     if (!threadData.empty())
         threadData.destroy();
 }
 /* static */
 void
 WorkerThread::ThreadMain(void *arg)
 {
     PR_SetCurrentThreadName("Analysis Helper");
     static_cast<WorkerThread *>(arg)->threadLoop();
 }
 void
 WorkerThread::handleAsmJSWorkload()
 {
 #ifdef JS_ION
     JS_ASSERT(WorkerThreadState().isLocked());
     JS_ASSERT(WorkerThreadState().canStartAsmJSCompile());
     JS_ASSERT(idle());
     asmData = WorkerThreadState().asmJSWorklist().popCopy();
     bool success = false;
     do {
         AutoUnlockWorkerThreadState unlock;
         PerThreadData::AutoEnterRuntime enter(threadData.addr(), asmData->runtime);
         jit::IonContext icx(asmData->mir->compartment->runtime(),
                             asmData->mir->compartment,
                             &asmData->mir->alloc());
         int64_t before = PRMJ_Now();
         if (!OptimizeMIR(asmData->mir))
             break;
         asmData->lir = GenerateLIR(asmData->mir);
         if (!asmData->lir)
             break;
         int64_t after = PRMJ_Now();
         asmData->compileTime = (after - before) / PRMJ_USEC_PER_MSEC;
         success = true;
     } while(0);
     // On failure, signal parent for harvesting in CancelOutstandingJobs().
     if (!success) {
         WorkerThreadState().noteAsmJSFailure(asmData->func);
         WorkerThreadState().notifyAll(GlobalWorkerThreadState::CONSUMER);
         asmData = nullptr;
         return;
     }
     // On success, move work to the finished list.
     WorkerThreadState().asmJSFinishedList().append(asmData);
     asmData = nullptr;
     // Notify the main thread in case it's blocked waiting for a LifoAlloc.
     WorkerThreadState().notifyAll(GlobalWorkerThreadState::CONSUMER);
 #else
     MOZ_CRASH();
 #endif // JS_ION
 }
 void
 WorkerThread::handleIonWorkload()
 {
 #ifdef JS_ION
     JS_ASSERT(WorkerThreadState().isLocked());
     JS_ASSERT(WorkerThreadState().canStartIonCompile());
     JS_ASSERT(idle());
     ionBuilder = WorkerThreadState().ionWorklist().popCopy();
     TraceLogger *logger = TraceLoggerForCurrentThread();
     AutoTraceLog logScript(logger, TraceLogCreateTextId(logger, ionBuilder->script()));
     AutoTraceLog logCompile(logger, TraceLogger::IonCompilation);
     JSRuntime *rt = ionBuilder->script()->compartment()->runtimeFromAnyThread();
     {
         AutoUnlockWorkerThreadState unlock;
         PerThreadData::AutoEnterRuntime enter(threadData.addr(),
                                               ionBuilder->script()->runtimeFromAnyThread());
         jit::IonContext ictx(jit::CompileRuntime::get(rt),
                              jit::CompileCompartment::get(ionBuilder->script()->compartment()),
                              &ionBuilder->alloc());
         ionBuilder->setBackgroundCodegen(jit::CompileBackEnd(ionBuilder));
     }
     FinishOffThreadIonCompile(ionBuilder);
     ionBuilder = nullptr;
     // Ping the main thread so that the compiled code can be incorporated
     // at the next interrupt callback. Don't interrupt Ion code for this, as
     // this incorporation can be delayed indefinitely without affecting
     // performance as long as the main thread is actually executing Ion code.
     rt->requestInterrupt(JSRuntime::RequestInterruptAnyThreadDontStopIon);
     // Notify the main thread in case it is waiting for the compilation to finish.
     WorkerThreadState().notifyAll(GlobalWorkerThreadState::CONSUMER);
 #else
     MOZ_CRASH();
 #endif // JS_ION
 }
 void
 ExclusiveContext::setWorkerThread(WorkerThread *workerThread)
 {
     workerThread_ = workerThread;
     perThreadData = workerThread->threadData.addr();
 }
 frontend::CompileError &
 ExclusiveContext::addPendingCompileError()
 {
     frontend::CompileError *error = js_new<frontend::CompileError>();
     if (!error)
         MOZ_CRASH();
     if (!workerThread()->parseTask->errors.append(error))
         MOZ_CRASH();
     return *error;
 }
 void
 ExclusiveContext::addPendingOverRecursed()
 {
     if (workerThread()->parseTask)
         workerThread()->parseTask->overRecursed = true;
 }
 void
 WorkerThread::handleParseWorkload()
 {
     JS_ASSERT(WorkerThreadState().isLocked());
     JS_ASSERT(WorkerThreadState().canStartParseTask());
     JS_ASSERT(idle());
     parseTask = WorkerThreadState().parseWorklist().popCopy();
     parseTask->cx->setWorkerThread(this);
     {
         AutoUnlockWorkerThreadState unlock;
         PerThreadData::AutoEnterRuntime enter(threadData.addr(),
                                               parseTask->exclusiveContextGlobal->runtimeFromAnyThread());
         SourceBufferHolder srcBuf(parseTask->chars, parseTask->length,
                                   SourceBufferHolder::NoOwnership);
         parseTask->script = frontend::CompileScript(parseTask->cx, &parseTask->alloc,
                                                     NullPtr(), NullPtr(),
                                                     parseTask->options,
                                                     srcBuf);
     }
     // The callback is invoked while we are still off the main thread.
     parseTask->callback(parseTask, parseTask->callbackData);
     // FinishOffThreadScript will need to be called on the script to
     // migrate it into the correct compartment.
     WorkerThreadState().parseFinishedList().append(parseTask);
     parseTask = nullptr;
     // Notify the main thread in case it is waiting for the parse/emit to finish.
     WorkerThreadState().notifyAll(GlobalWorkerThreadState::CONSUMER);
 }
 void
 WorkerThread::handleCompressionWorkload()
 {
     JS_ASSERT(WorkerThreadState().isLocked());
     JS_ASSERT(WorkerThreadState().canStartCompressionTask());
     JS_ASSERT(idle());
     compressionTask = WorkerThreadState().compressionWorklist().popCopy();
     compressionTask->workerThread = this;
     {
         AutoUnlockWorkerThreadState unlock;
         if (!compressionTask->work())
             compressionTask->setOOM();
     }
     compressionTask->workerThread = nullptr;
     compressionTask = nullptr;
     // Notify the main thread in case it is waiting for the compression to finish.
     WorkerThreadState().notifyAll(GlobalWorkerThreadState::CONSUMER);
 }
 bool
 js::StartOffThreadCompression(ExclusiveContext *cx, SourceCompressionTask *task)
 {
     EnsureWorkerThreadsInitialized(cx);
     AutoLockWorkerThreadState lock;
     if (!WorkerThreadState().compressionWorklist().append(task))
         return false;
     WorkerThreadState().notifyOne(GlobalWorkerThreadState::PRODUCER);
     return true;
 }
 bool
 GlobalWorkerThreadState::compressionInProgress(SourceCompressionTask *task)
 {
     JS_ASSERT(isLocked());
     for (size_t i = 0; i < compressionWorklist().length(); i++) {
         if (compressionWorklist()[i] == task)
             return true;
     }
     for (size_t i = 0; i < threadCount; i++) {
         if (threads[i].compressionTask == task)
             return true;
     }
     return false;
 }
 bool
 SourceCompressionTask::complete()
 {
     JS_ASSERT_IF(!ss, !chars);
     if (active()) {
         AutoLockWorkerThreadState lock;
         while (WorkerThreadState().compressionInProgress(this))
             WorkerThreadState().wait(GlobalWorkerThreadState::CONSUMER);
         ss->ready_ = true;
         // Update memory accounting.
         if (!oom)
             cx->updateMallocCounter(ss->computedSizeOfData());
         ss = nullptr;
         chars = nullptr;
     }
     if (oom) {
         js_ReportOutOfMemory(cx);
         return false;
     }
     return true;
 }
 SourceCompressionTask *
 GlobalWorkerThreadState::compressionTaskForSource(ScriptSource *ss)
 {
     JS_ASSERT(isLocked());
     for (size_t i = 0; i < compressionWorklist().length(); i++) {
         SourceCompressionTask *task = compressionWorklist()[i];
         if (task->source() == ss)
             return task;
     }
     for (size_t i = 0; i < threadCount; i++) {
         SourceCompressionTask *task = threads[i].compressionTask;
         if (task && task->source() == ss)
             return task;
     }
     return nullptr;
 }
 const jschar *
 ScriptSource::getOffThreadCompressionChars(ExclusiveContext *cx)
 {
     // If this is being compressed off thread, return its uncompressed chars.
     if (ready()) {
         // Compression has already finished on the source.
         return nullptr;
     }
     AutoLockWorkerThreadState lock;
     // Look for a token that hasn't finished compressing and whose source is
     // the given ScriptSource.
     if (SourceCompressionTask *task = WorkerThreadState().compressionTaskForSource(this))
         return task->uncompressedChars();
     // Compressing has finished, so this ScriptSource is ready. Avoid future
     // queries on the worker thread state when getting the chars.
     ready_ = true;
     return nullptr;
 }
 void
 WorkerThread::threadLoop()
 {
     JS::AutoAssertNoGC nogc;
     AutoLockWorkerThreadState lock;
     js::TlsPerThreadData.set(threadData.addr());
     // Compute the thread's stack limit, for over-recursed checks.
     uintptr_t stackLimit = GetNativeStackBase();
 #if JS_STACK_GROWTH_DIRECTION > 0
     stackLimit += WORKER_STACK_QUOTA;
 #else
     stackLimit -= WORKER_STACK_QUOTA;
 #endif
     for (size_t i = 0; i < ArrayLength(threadData.ref().nativeStackLimit); i++)
         threadData.ref().nativeStackLimit[i] = stackLimit;
     while (true) {
         JS_ASSERT(!ionBuilder && !asmData);
         // Block until a task is available.
         while (true) {
             if (terminate)
                 return;
             if (WorkerThreadState().canStartIonCompile() ||
                 WorkerThreadState().canStartAsmJSCompile() ||
                 WorkerThreadState().canStartParseTask() ||
                 WorkerThreadState().canStartCompressionTask())
             {
                 break;
             }
             WorkerThreadState().wait(GlobalWorkerThreadState::PRODUCER);
         }
         // Dispatch tasks, prioritizing AsmJS work.
         if (WorkerThreadState().canStartAsmJSCompile())
             handleAsmJSWorkload();
         else if (WorkerThreadState().canStartIonCompile())
             handleIonWorkload();
         else if (WorkerThreadState().canStartParseTask())
             handleParseWorkload();
         else if (WorkerThreadState().canStartCompressionTask())
             handleCompressionWorkload();
         else
             MOZ_ASSUME_UNREACHABLE("No task to perform");
     }
 }
 #else /* JS_THREADSAFE */
 using namespace js;
 #ifdef JS_ION
 bool
 js::StartOffThreadAsmJSCompile(ExclusiveContext *cx, AsmJSParallelTask *asmData)
 {
     MOZ_ASSUME_UNREACHABLE("Off thread compilation not available in non-THREADSAFE builds");
 }
 bool
 js::StartOffThreadIonCompile(JSContext *cx, jit::IonBuilder *builder)
 {
     MOZ_ASSUME_UNREACHABLE("Off thread compilation not available in non-THREADSAFE builds");
 }
 #endif // JS_ION
 void
 js::CancelOffThreadIonCompile(JSCompartment *compartment, JSScript *script)
 {
 }
 void
 js::CancelOffThreadParses(JSRuntime *rt)
 {
 }
 bool
 js::StartOffThreadParseScript(JSContext *cx, const ReadOnlyCompileOptions &options,
                               const jschar *chars, size_t length,
                               JS::OffThreadCompileCallback callback, void *callbackData)
 {
     MOZ_ASSUME_UNREACHABLE("Off thread compilation not available in non-THREADSAFE builds");
 }
 bool
 js::StartOffThreadCompression(ExclusiveContext *cx, SourceCompressionTask *task)
 {
     MOZ_ASSUME_UNREACHABLE("Off thread compression not available");
 }
 bool
 SourceCompressionTask::complete()
 {
     JS_ASSERT(!active() && !oom);
     return true;
 }
 const jschar *
 ScriptSource::getOffThreadCompressionChars(ExclusiveContext *cx)
 {
     JS_ASSERT(ready());
     return nullptr;
 }
 frontend::CompileError &
 ExclusiveContext::addPendingCompileError()
 {
     MOZ_ASSUME_UNREACHABLE("Off thread compilation not available.");
 }
 void
 ExclusiveContext::addPendingOverRecursed()
 {
     MOZ_ASSUME_UNREACHABLE("Off thread compilation not available.");
 }
 #endif /* JS_THREADSAFE */

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js/src/jsworkers.cpp@6474c204b198 (annotated)

js/src/jsworkers.cpp