The JSC shell should listen for memory pressure events and respond to them
[WebKit-https.git] / Source / JavaScriptCore / runtime / VM.cpp
index 24b9f60..d83269b 100644 (file)
 #include "TypeProfilerLog.h"
 #include "UnlinkedCodeBlock.h"
 #include "VMEntryScope.h"
+#include "VMInlines.h"
 #include "VMInspector.h"
 #include "VariableEnvironment.h"
 #include "WasmWorklist.h"
 #include <wtf/text/AtomicStringTable.h>
 #include <wtf/text/SymbolRegistry.h>
 
-#if !ENABLE(JIT)
+#if ENABLE(C_LOOP)
 #include "CLoopStack.h"
 #include "CLoopStackInlines.h"
 #endif
@@ -175,6 +176,15 @@ using namespace WTF;
 
 namespace JSC {
 
+#if ENABLE(JIT)
+#if !ASSERT_DISABLED
+bool VM::s_canUseJITIsSet = false;
+#endif
+bool VM::s_canUseJIT = false;
+#endif
+
+Atomic<unsigned> VM::s_numberOfIDs;
+
 // Note: Platform.h will enforce that ENABLE(ASSEMBLER) is true if either
 // ENABLE(JIT) or ENABLE(YARR_JIT) or both are enabled. The code below
 // just checks for ENABLE(JIT) or ENABLE(YARR_JIT) with this premise in mind.
@@ -210,17 +220,14 @@ bool VM::canUseAssembler()
 #endif
 }
 
-bool VM::canUseJIT()
+void VM::computeCanUseJIT()
 {
 #if ENABLE(JIT)
-    static std::once_flag onceKey;
-    static bool enabled = false;
-    std::call_once(onceKey, [] {
-        enabled = VM::canUseAssembler() && Options::useJIT();
-    });
-    return enabled;
-#else
-    return false; // interpreter only
+#if !ASSERT_DISABLED
+    RELEASE_ASSERT(!s_canUseJITIsSet);
+    s_canUseJITIsSet = true;
+#endif
+    s_canUseJIT = VM::canUseAssembler() && Options::useJIT();
 #endif
 }
 
@@ -243,8 +250,20 @@ bool VM::isInMiniMode()
     return !canUseJIT() || Options::forceMiniVMMode();
 }
 
+inline unsigned VM::nextID()
+{
+    for (;;) {
+        unsigned currentNumberOfIDs = s_numberOfIDs.load();
+        unsigned newID = currentNumberOfIDs + 1;
+        if (s_numberOfIDs.compareExchangeWeak(currentNumberOfIDs, newID))
+            return newID;
+    }
+}
+
+
 VM::VM(VMType vmType, HeapType heapType)
-    : m_apiLock(adoptRef(new JSLock(this)))
+    : m_id(nextID())
+    , m_apiLock(adoptRef(new JSLock(this)))
 #if USE(CF)
     , m_runLoop(CFRunLoopGetCurrent())
 #endif // USE(CF)
@@ -363,6 +382,8 @@ VM::VM(VMType vmType, HeapType heapType)
     updateSoftReservedZoneSize(Options::softReservedZoneSize());
     setLastStackTop(stack.origin());
 
+    JSRunLoopTimer::Manager::shared().registerVM(*this);
+
     // Need to be careful to keep everything consistent here
     JSLockHolder lock(this);
     AtomicStringTable* existingEntryAtomicStringTable = Thread::current().setCurrentAtomicStringTable(m_atomicStringTable);
@@ -413,6 +434,7 @@ VM::VM(VMType vmType, HeapType heapType)
     exceptionStructure.set(*this, Exception::createStructure(*this, 0, jsNull()));
     promiseDeferredStructure.set(*this, JSPromiseDeferred::createStructure(*this, 0, jsNull()));
     internalPromiseDeferredStructure.set(*this, JSInternalPromiseDeferred::createStructure(*this, 0, jsNull()));
+    nativeStdFunctionCellStructure.set(*this, NativeStdFunctionCell::createStructure(*this, 0, jsNull()));
     programCodeBlockStructure.set(*this, ProgramCodeBlock::createStructure(*this, 0, jsNull()));
     moduleProgramCodeBlockStructure.set(*this, ModuleProgramCodeBlock::createStructure(*this, 0, jsNull()));
     evalCodeBlockStructure.set(*this, EvalCodeBlock::createStructure(*this, 0, jsNull()));
@@ -426,8 +448,8 @@ VM::VM(VMType vmType, HeapType heapType)
 
     sentinelSetBucket.set(*this, JSSet::BucketType::createSentinel(*this));
     sentinelMapBucket.set(*this, JSMap::BucketType::createSentinel(*this));
+    sentinelImmutableButterfly.set(*this, JSImmutableButterfly::createSentinel(*this));
 
-    nativeStdFunctionCellStructure.set(*this, NativeStdFunctionCell::createStructure(*this, 0, jsNull()));
     smallStrings.initializeCommonStrings(*this);
 
     Thread::current().setCurrentAtomicStringTable(existingEntryAtomicStringTable);
@@ -440,7 +462,7 @@ VM::VM(VMType vmType, HeapType heapType)
     ftlThunks = std::make_unique<FTL::Thunks>();
 #endif // ENABLE(FTL_JIT)
     
-#if ENABLE(JIT)
+#if !ENABLE(C_LOOP)
     initializeHostCallReturnValue(); // This is needed to convince the linker not to drop host call return support.
 #endif
     
@@ -563,6 +585,8 @@ VM::~VM()
     ASSERT(currentThreadIsHoldingAPILock());
     m_apiLock->willDestroyVM(this);
     heap.lastChanceToFinalize();
+
+    JSRunLoopTimer::Manager::shared().unregisterVM(*this);
     
     delete interpreter;
 #ifndef NDEBUG
@@ -718,9 +742,8 @@ NativeExecutable* VM::getHostFunction(NativeFunction function, Intrinsic intrins
             intrinsic != NoIntrinsic ? thunkGeneratorForIntrinsic(intrinsic) : 0,
             intrinsic, signature, name);
     }
-#else // ENABLE(JIT)
-    UNUSED_PARAM(intrinsic);
 #endif // ENABLE(JIT)
+    UNUSED_PARAM(intrinsic);
     return NativeExecutable::create(*this,
         adoptRef(*new NativeJITCode(LLInt::getCodeRef<JSEntryPtrTag>(llint_native_call_trampoline), JITCode::HostCallThunk)), function,
         adoptRef(*new NativeJITCode(LLInt::getCodeRef<JSEntryPtrTag>(llint_native_construct_trampoline), JITCode::HostCallThunk)), constructor,
@@ -753,14 +776,14 @@ void VM::resetDateCache()
     dateInstanceCache.reset();
 }
 
-void VM::whenIdle(std::function<void()> callback)
+void VM::whenIdle(Function<void()>&& callback)
 {
     if (!entryScope) {
         callback();
         return;
     }
 
-    entryScope->addDidPopListener(callback);
+    entryScope->addDidPopListener(WTFMove(callback));
 }
 
 void VM::deleteAllLinkedCode(DeleteAllCodeEffort effort)
@@ -808,15 +831,16 @@ void VM::clearSourceProviderCaches()
 
 void VM::throwException(ExecState* exec, Exception* exception)
 {
+    ASSERT(exec == topCallFrame || exec->isGlobalExec());
+    CallFrame* throwOriginFrame = exec->isGlobalExec() ? exec : topJSCallFrame();
+
     if (Options::breakOnThrow()) {
-        CodeBlock* codeBlock = exec->codeBlock();
-        dataLog("Throwing exception in call frame ", RawPointer(exec), " for code block ", codeBlock, "\n");
+        CodeBlock* codeBlock = throwOriginFrame ? throwOriginFrame->codeBlock() : nullptr;
+        dataLog("Throwing exception in call frame ", RawPointer(throwOriginFrame), " for code block ", codeBlock, "\n");
         CRASH();
     }
 
-    ASSERT(exec == topCallFrame || exec == exec->lexicalGlobalObject()->globalExec() || exec == exec->vmEntryGlobalObject()->globalExec());
-
-    interpreter->notifyDebuggerOfExceptionToBeThrown(*this, exec, exception);
+    interpreter->notifyDebuggerOfExceptionToBeThrown(*this, throwOriginFrame, exception);
 
     setException(exception);
 
@@ -852,7 +876,7 @@ size_t VM::updateSoftReservedZoneSize(size_t softReservedZoneSize)
 {
     size_t oldSoftReservedZoneSize = m_currentSoftReservedZoneSize;
     m_currentSoftReservedZoneSize = softReservedZoneSize;
-#if !ENABLE(JIT)
+#if ENABLE(C_LOOP)
     interpreter->cloopStack().setSoftReservedZoneSize(softReservedZoneSize);
 #endif
 
@@ -1023,7 +1047,8 @@ void VM::addImpureProperty(const String& propertyName)
         watchpointSet->fireAll(*this, "Impure property added");
 }
 
-static bool enableProfilerWithRespectToCount(unsigned& counter, std::function<void()> doEnableWork)
+template<typename Func>
+static bool enableProfilerWithRespectToCount(unsigned& counter, const Func& doEnableWork)
 {
     bool needsToRecompile = false;
     if (!counter) {
@@ -1035,7 +1060,8 @@ static bool enableProfilerWithRespectToCount(unsigned& counter, std::function<vo
     return needsToRecompile;
 }
 
-static bool disableProfilerWithRespectToCount(unsigned& counter, std::function<void()> doDisableWork)
+template<typename Func>
+static bool disableProfilerWithRespectToCount(unsigned& counter, const Func& doDisableWork)
 {
     RELEASE_ASSERT(counter > 0);
     bool needsToRecompile = false;
@@ -1091,7 +1117,7 @@ void VM::dumpTypeProfilerData()
     if (!typeProfiler())
         return;
 
-    typeProfilerLog()->processLogEntries("VM Dump Types"_s);
+    typeProfilerLog()->processLogEntries(*this, "VM Dump Types"_s);
     typeProfiler()->dumpTypeProfilerData(*this);
 }
 
@@ -1102,8 +1128,11 @@ void VM::queueMicrotask(JSGlobalObject& globalObject, Ref<Microtask>&& task)
 
 void VM::drainMicrotasks()
 {
-    while (!m_microtaskQueue.isEmpty())
+    while (!m_microtaskQueue.isEmpty()) {
         m_microtaskQueue.takeFirst()->run();
+        if (m_onEachMicrotaskTick)
+            m_onEachMicrotaskTick(*this);
+    }
 }
 
 void QueuedTask::run()
@@ -1119,7 +1148,7 @@ void sanitizeStackForVM(VM* vm)
         ASSERT(vm->currentThreadIsHoldingAPILock());
         ASSERT_UNUSED(stackBounds, stackBounds.contains(vm->lastStackTop()));
     }
-#if !ENABLE(JIT)
+#if ENABLE(C_LOOP)
     vm->interpreter->cloopStack().sanitizeStack();
 #else
     sanitizeStackForVMImpl(vm);
@@ -1128,19 +1157,19 @@ void sanitizeStackForVM(VM* vm)
 
 size_t VM::committedStackByteCount()
 {
-#if ENABLE(JIT)
+#if !ENABLE(C_LOOP)
     // When using the C stack, we don't know how many stack pages are actually
     // committed. So, we use the current stack usage as an estimate.
     ASSERT(Thread::current().stack().isGrowingDownward());
-    int8_t* current = reinterpret_cast<int8_t*>(&current);
-    int8_t* high = reinterpret_cast<int8_t*>(Thread::current().stack().origin());
+    uint8_t* current = bitwise_cast<uint8_t*>(currentStackPointer());
+    uint8_t* high = bitwise_cast<uint8_t*>(Thread::current().stack().origin());
     return high - current;
 #else
     return CLoopStack::committedByteCount();
 #endif
 }
 
-#if !ENABLE(JIT)
+#if ENABLE(C_LOOP)
 bool VM::ensureStackCapacityForCLoop(Register* newTopOfStack)
 {
     return interpreter->cloopStack().ensureCapacityFor(newTopOfStack);
@@ -1150,7 +1179,7 @@ bool VM::isSafeToRecurseSoftCLoop() const
 {
     return interpreter->cloopStack().isSafeToRecurse();
 }
-#endif // !ENABLE(JIT)
+#endif // ENABLE(C_LOOP)
 
 #if ENABLE(EXCEPTION_SCOPE_VERIFICATION)
 void VM::verifyExceptionCheckNeedIsSatisfied(unsigned recursionDepth, ExceptionEventLocation& location)
@@ -1189,27 +1218,11 @@ void VM::verifyExceptionCheckNeedIsSatisfied(unsigned recursionDepth, ExceptionE
 #endif
 
 #if USE(CF)
-void VM::registerRunLoopTimer(JSRunLoopTimer* timer)
-{
-    ASSERT(runLoop());
-    ASSERT(!m_runLoopTimers.contains(timer));
-    m_runLoopTimers.add(timer);
-    timer->setRunLoop(runLoop());
-}
-
-void VM::unregisterRunLoopTimer(JSRunLoopTimer* timer)
-{
-    ASSERT(m_runLoopTimers.contains(timer));
-    m_runLoopTimers.remove(timer);
-    timer->setRunLoop(nullptr);
-}
-
 void VM::setRunLoop(CFRunLoopRef runLoop)
 {
     ASSERT(runLoop);
     m_runLoop = runLoop;
-    for (auto timer : m_runLoopTimers)
-        timer->setRunLoop(runLoop);
+    JSRunLoopTimer::Manager::shared().didChangeRunLoop(*this, runLoop);
 }
 #endif // USE(CF)
 
@@ -1243,4 +1256,15 @@ void VM::clearScratchBuffers()
         scratchBuffer->setActiveLength(0);
 }
 
+JSGlobalObject* VM::vmEntryGlobalObject(const CallFrame* callFrame) const
+{
+    if (callFrame && callFrame->isGlobalExec()) {
+        ASSERT(callFrame->callee().isCell() && callFrame->callee().asCell()->isObject());
+        ASSERT(callFrame == callFrame->lexicalGlobalObject()->globalExec());
+        return callFrame->lexicalGlobalObject();
+    }
+    ASSERT(entryScope);
+    return entryScope->globalObject();
+}
+
 } // namespace JSC