blob: d13d6d5f7fd78011d766242ed990133d8ddf53d2 [file] [log] [blame]
/*
* Copyright (C) 2011-2020 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "Repatch.h"
#if ENABLE(JIT)
#include "BinarySwitch.h"
#include "CCallHelpers.h"
#include "CacheableIdentifierInlines.h"
#include "CallFrameShuffler.h"
#include "DFGOperations.h"
#include "DFGSpeculativeJIT.h"
#include "DOMJITGetterSetter.h"
#include "DirectArguments.h"
#include "ExecutableBaseInlines.h"
#include "FTLThunks.h"
#include "FullCodeOrigin.h"
#include "FunctionCodeBlock.h"
#include "GCAwareJITStubRoutine.h"
#include "GetterSetter.h"
#include "GetterSetterAccessCase.h"
#include "ICStats.h"
#include "InlineAccess.h"
#include "InstanceOfAccessCase.h"
#include "IntrinsicGetterAccessCase.h"
#include "JIT.h"
#include "JITInlines.h"
#include "JSCInlines.h"
#include "JSModuleNamespaceObject.h"
#include "JSWebAssembly.h"
#include "JSWebAssemblyModule.h"
#include "LinkBuffer.h"
#include "ModuleNamespaceAccessCase.h"
#include "PolymorphicAccess.h"
#include "ScopedArguments.h"
#include "ScratchRegisterAllocator.h"
#include "StackAlignment.h"
#include "StructureRareDataInlines.h"
#include "StructureStubClearingWatchpoint.h"
#include "StructureStubInfo.h"
#include "SuperSampler.h"
#include "ThunkGenerators.h"
#include "WebAssemblyFunction.h"
#include <wtf/CommaPrinter.h>
#include <wtf/ListDump.h>
#include <wtf/StringPrintStream.h>
namespace JSC {
static FunctionPtr<CFunctionPtrTag> readPutICCallTarget(CodeBlock* codeBlock, CodeLocationCall<JSInternalPtrTag> call)
{
FunctionPtr<OperationPtrTag> target = MacroAssembler::readCallTarget<OperationPtrTag>(call);
#if ENABLE(FTL_JIT)
if (codeBlock->jitType() == JITType::FTLJIT) {
MacroAssemblerCodePtr<JITThunkPtrTag> thunk = MacroAssemblerCodePtr<OperationPtrTag>::createFromExecutableAddress(target.executableAddress()).retagged<JITThunkPtrTag>();
return codeBlock->vm().ftlThunks->keyForSlowPathCallThunk(thunk).callTarget().retagged<CFunctionPtrTag>();
}
#else
UNUSED_PARAM(codeBlock);
#endif // ENABLE(FTL_JIT)
return target.retagged<CFunctionPtrTag>();
}
void ftlThunkAwareRepatchCall(CodeBlock* codeBlock, CodeLocationCall<JSInternalPtrTag> call, FunctionPtr<CFunctionPtrTag> newCalleeFunction)
{
#if ENABLE(FTL_JIT)
if (codeBlock->jitType() == JITType::FTLJIT) {
VM& vm = codeBlock->vm();
FTL::Thunks& thunks = *vm.ftlThunks;
FunctionPtr<OperationPtrTag> target = MacroAssembler::readCallTarget<OperationPtrTag>(call);
auto slowPathThunk = MacroAssemblerCodePtr<JITThunkPtrTag>::createFromExecutableAddress(target.retaggedExecutableAddress<JITThunkPtrTag>());
FTL::SlowPathCallKey key = thunks.keyForSlowPathCallThunk(slowPathThunk);
key = key.withCallTarget(newCalleeFunction);
MacroAssembler::repatchCall(call, FunctionPtr<OperationPtrTag>(thunks.getSlowPathCallThunk(vm, key).retaggedCode<OperationPtrTag>()));
return;
}
#else // ENABLE(FTL_JIT)
UNUSED_PARAM(codeBlock);
#endif // ENABLE(FTL_JIT)
MacroAssembler::repatchCall(call, newCalleeFunction.retagged<OperationPtrTag>());
}
enum InlineCacheAction {
GiveUpOnCache,
RetryCacheLater,
AttemptToCache
};
static InlineCacheAction actionForCell(VM& vm, JSCell* cell)
{
Structure* structure = cell->structure(vm);
TypeInfo typeInfo = structure->typeInfo();
if (typeInfo.prohibitsPropertyCaching())
return GiveUpOnCache;
if (structure->isUncacheableDictionary()) {
if (structure->hasBeenFlattenedBefore())
return GiveUpOnCache;
// Flattening could have changed the offset, so return early for another try.
asObject(cell)->flattenDictionaryObject(vm);
return RetryCacheLater;
}
if (!structure->propertyAccessesAreCacheable())
return GiveUpOnCache;
return AttemptToCache;
}
static bool forceICFailure(JSGlobalObject*)
{
return Options::forceICFailure();
}
ALWAYS_INLINE static void fireWatchpointsAndClearStubIfNeeded(VM& vm, StructureStubInfo& stubInfo, CodeBlock* codeBlock, AccessGenerationResult& result)
{
if (result.shouldResetStubAndFireWatchpoints()) {
result.fireWatchpoints(vm);
stubInfo.reset(codeBlock);
}
}
inline FunctionPtr<CFunctionPtrTag> appropriateOptimizingGetByFunction(GetByKind kind)
{
switch (kind) {
case GetByKind::Normal:
return operationGetByIdOptimize;
case GetByKind::WithThis:
return operationGetByIdWithThisOptimize;
case GetByKind::Try:
return operationTryGetByIdOptimize;
case GetByKind::Direct:
return operationGetByIdDirectOptimize;
case GetByKind::NormalByVal:
return operationGetByValOptimize;
}
RELEASE_ASSERT_NOT_REACHED();
}
inline FunctionPtr<CFunctionPtrTag> appropriateGetByFunction(GetByKind kind)
{
switch (kind) {
case GetByKind::Normal:
return operationGetById;
case GetByKind::WithThis:
return operationGetByIdWithThis;
case GetByKind::Try:
return operationTryGetById;
case GetByKind::Direct:
return operationGetByIdDirect;
case GetByKind::NormalByVal:
return operationGetByValGeneric;
}
RELEASE_ASSERT_NOT_REACHED();
}
static InlineCacheAction tryCacheGetBy(JSGlobalObject* globalObject, CodeBlock* codeBlock, JSValue baseValue, CacheableIdentifier propertyName, const PropertySlot& slot, StructureStubInfo& stubInfo, GetByKind kind)
{
VM& vm = globalObject->vm();
AccessGenerationResult result;
{
GCSafeConcurrentJSLocker locker(codeBlock->m_lock, globalObject->vm().heap);
if (forceICFailure(globalObject))
return GiveUpOnCache;
// FIXME: Cache property access for immediates.
if (!baseValue.isCell())
return GiveUpOnCache;
JSCell* baseCell = baseValue.asCell();
std::unique_ptr<AccessCase> newCase;
if (propertyName == vm.propertyNames->length) {
if (isJSArray(baseCell)) {
if (stubInfo.cacheType() == CacheType::Unset
&& slot.slotBase() == baseCell
&& InlineAccess::isCacheableArrayLength(stubInfo, jsCast<JSArray*>(baseCell))) {
bool generatedCodeInline = InlineAccess::generateArrayLength(stubInfo, jsCast<JSArray*>(baseCell));
if (generatedCodeInline) {
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, appropriateOptimizingGetByFunction(kind));
stubInfo.initArrayLength();
return RetryCacheLater;
}
}
newCase = AccessCase::create(vm, codeBlock, AccessCase::ArrayLength, propertyName);
} else if (isJSString(baseCell)) {
if (stubInfo.cacheType() == CacheType::Unset && InlineAccess::isCacheableStringLength(stubInfo)) {
bool generatedCodeInline = InlineAccess::generateStringLength(stubInfo);
if (generatedCodeInline) {
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, appropriateOptimizingGetByFunction(kind));
stubInfo.initStringLength();
return RetryCacheLater;
}
}
newCase = AccessCase::create(vm, codeBlock, AccessCase::StringLength, propertyName);
} else if (DirectArguments* arguments = jsDynamicCast<DirectArguments*>(vm, baseCell)) {
// If there were overrides, then we can handle this as a normal property load! Guarding
// this with such a check enables us to add an IC case for that load if needed.
if (!arguments->overrodeThings())
newCase = AccessCase::create(vm, codeBlock, AccessCase::DirectArgumentsLength, propertyName);
} else if (ScopedArguments* arguments = jsDynamicCast<ScopedArguments*>(vm, baseCell)) {
// Ditto.
if (!arguments->overrodeThings())
newCase = AccessCase::create(vm, codeBlock, AccessCase::ScopedArgumentsLength, propertyName);
}
}
if (!propertyName.isSymbol() && baseCell->inherits<JSModuleNamespaceObject>(vm) && !slot.isUnset()) {
if (auto moduleNamespaceSlot = slot.moduleNamespaceSlot())
newCase = ModuleNamespaceAccessCase::create(vm, codeBlock, propertyName, jsCast<JSModuleNamespaceObject*>(baseCell), moduleNamespaceSlot->environment, ScopeOffset(moduleNamespaceSlot->scopeOffset));
}
if (!newCase) {
if (!slot.isCacheable() && !slot.isUnset())
return GiveUpOnCache;
ObjectPropertyConditionSet conditionSet;
Structure* structure = baseCell->structure(vm);
bool loadTargetFromProxy = false;
if (baseCell->type() == PureForwardingProxyType) {
baseValue = jsCast<JSProxy*>(baseCell)->target();
baseCell = baseValue.asCell();
structure = baseCell->structure(vm);
loadTargetFromProxy = true;
}
InlineCacheAction action = actionForCell(vm, baseCell);
if (action != AttemptToCache)
return action;
// Optimize self access.
if (stubInfo.cacheType() == CacheType::Unset
&& slot.isCacheableValue()
&& slot.slotBase() == baseValue
&& !slot.watchpointSet()
&& !structure->needImpurePropertyWatchpoint()
&& !loadTargetFromProxy) {
bool generatedCodeInline = InlineAccess::generateSelfPropertyAccess(stubInfo, structure, slot.cachedOffset());
if (generatedCodeInline) {
LOG_IC((ICEvent::GetBySelfPatch, structure->classInfo(), Identifier::fromUid(vm, propertyName.uid()), slot.slotBase() == baseValue));
structure->startWatchingPropertyForReplacements(vm, slot.cachedOffset());
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, appropriateOptimizingGetByFunction(kind));
stubInfo.initGetByIdSelf(codeBlock, structure, slot.cachedOffset(), propertyName);
return RetryCacheLater;
}
}
std::unique_ptr<PolyProtoAccessChain> prototypeAccessChain;
PropertyOffset offset = slot.isUnset() ? invalidOffset : slot.cachedOffset();
if (slot.isCustom() && slot.slotBase() == baseValue) {
// To cache self customs, we must disallow dictionaries because we
// need to be informed if the custom goes away since we cache the
// constant function pointer.
if (!prepareChainForCaching(globalObject, slot.slotBase(), slot.slotBase()))
return GiveUpOnCache;
}
if (slot.isUnset() || slot.slotBase() != baseValue) {
if (structure->typeInfo().prohibitsPropertyCaching())
return GiveUpOnCache;
if (structure->isDictionary()) {
if (structure->hasBeenFlattenedBefore())
return GiveUpOnCache;
structure->flattenDictionaryStructure(vm, jsCast<JSObject*>(baseCell));
return RetryCacheLater; // We may have changed property offsets.
}
if (slot.isUnset() && structure->typeInfo().getOwnPropertySlotIsImpureForPropertyAbsence())
return GiveUpOnCache;
// If a kind is GetByKind::Direct, we do not need to investigate prototype chains further.
// Cacheability just depends on the head structure.
if (kind != GetByKind::Direct) {
auto cacheStatus = prepareChainForCaching(globalObject, baseCell, slot);
if (!cacheStatus)
return GiveUpOnCache;
if (cacheStatus->flattenedDictionary) {
// Property offsets may have changed due to flattening. We'll cache later.
return RetryCacheLater;
}
if (cacheStatus->usesPolyProto) {
prototypeAccessChain = PolyProtoAccessChain::create(globalObject, baseCell, slot);
if (!prototypeAccessChain)
return GiveUpOnCache;
RELEASE_ASSERT(slot.isCacheableCustom() || prototypeAccessChain->slotBaseStructure(structure)->get(vm, propertyName.uid()) == offset);
} else {
// We use ObjectPropertyConditionSet instead for faster accesses.
prototypeAccessChain = nullptr;
// FIXME: Maybe this `if` should be inside generateConditionsForPropertyBlah.
// https://bugs.webkit.org/show_bug.cgi?id=185215
if (slot.isUnset()) {
conditionSet = generateConditionsForPropertyMiss(
vm, codeBlock, globalObject, structure, propertyName.uid());
} else if (!slot.isCacheableCustom()) {
conditionSet = generateConditionsForPrototypePropertyHit(
vm, codeBlock, globalObject, structure, slot.slotBase(),
propertyName.uid());
RELEASE_ASSERT(!conditionSet.isValid() || conditionSet.slotBaseCondition().offset() == offset);
} else {
conditionSet = generateConditionsForPrototypePropertyHitCustom(
vm, codeBlock, globalObject, structure, slot.slotBase(),
propertyName.uid(), slot.attributes());
}
if (!conditionSet.isValid())
return GiveUpOnCache;
}
}
}
JSFunction* getter = nullptr;
if (slot.isCacheableGetter())
getter = jsDynamicCast<JSFunction*>(vm, slot.getterSetter()->getter());
Optional<DOMAttributeAnnotation> domAttribute;
if (slot.isCacheableCustom() && slot.domAttribute())
domAttribute = slot.domAttribute();
if (kind == GetByKind::Try) {
AccessCase::AccessType type;
if (slot.isCacheableValue())
type = AccessCase::Load;
else if (slot.isUnset())
type = AccessCase::Miss;
else if (slot.isCacheableGetter())
type = AccessCase::GetGetter;
else
RELEASE_ASSERT_NOT_REACHED();
newCase = ProxyableAccessCase::create(vm, codeBlock, type, propertyName, offset, structure, conditionSet, loadTargetFromProxy, slot.watchpointSet(), WTFMove(prototypeAccessChain));
} else if (!loadTargetFromProxy && getter && IntrinsicGetterAccessCase::canEmitIntrinsicGetter(getter, structure))
newCase = IntrinsicGetterAccessCase::create(vm, codeBlock, propertyName, slot.cachedOffset(), structure, conditionSet, getter, WTFMove(prototypeAccessChain));
else {
if (slot.isCacheableValue() || slot.isUnset()) {
newCase = ProxyableAccessCase::create(vm, codeBlock, slot.isUnset() ? AccessCase::Miss : AccessCase::Load,
propertyName, offset, structure, conditionSet, loadTargetFromProxy, slot.watchpointSet(), WTFMove(prototypeAccessChain));
} else {
AccessCase::AccessType type;
if (slot.isCacheableGetter())
type = AccessCase::Getter;
else if (slot.attributes() & PropertyAttribute::CustomAccessor)
type = AccessCase::CustomAccessorGetter;
else
type = AccessCase::CustomValueGetter;
if (kind == GetByKind::WithThis && type == AccessCase::CustomAccessorGetter && domAttribute)
return GiveUpOnCache;
newCase = GetterSetterAccessCase::create(
vm, codeBlock, type, propertyName, offset, structure, conditionSet, loadTargetFromProxy,
slot.watchpointSet(), slot.isCacheableCustom() ? slot.customGetter() : nullptr,
slot.isCacheableCustom() && slot.slotBase() != baseValue ? slot.slotBase() : nullptr,
domAttribute, WTFMove(prototypeAccessChain));
}
}
}
LOG_IC((ICEvent::GetByAddAccessCase, baseValue.classInfoOrNull(vm), Identifier::fromUid(vm, propertyName.uid()), slot.slotBase() == baseValue));
result = stubInfo.addAccessCase(locker, codeBlock, propertyName, WTFMove(newCase));
if (result.generatedSomeCode()) {
LOG_IC((ICEvent::GetByReplaceWithJump, baseValue.classInfoOrNull(vm), Identifier::fromUid(vm, propertyName.uid()), slot.slotBase() == baseValue));
RELEASE_ASSERT(result.code());
InlineAccess::rewireStubAsJump(stubInfo, CodeLocationLabel<JITStubRoutinePtrTag>(result.code()));
}
}
fireWatchpointsAndClearStubIfNeeded(vm, stubInfo, codeBlock, result);
return result.shouldGiveUpNow() ? GiveUpOnCache : RetryCacheLater;
}
void repatchGetBy(JSGlobalObject* globalObject, CodeBlock* codeBlock, JSValue baseValue, CacheableIdentifier propertyName, const PropertySlot& slot, StructureStubInfo& stubInfo, GetByKind kind)
{
SuperSamplerScope superSamplerScope(false);
if (tryCacheGetBy(globalObject, codeBlock, baseValue, propertyName, slot, stubInfo, kind) == GiveUpOnCache)
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, appropriateGetByFunction(kind));
}
static InlineCacheAction tryCacheArrayGetByVal(JSGlobalObject* globalObject, CodeBlock* codeBlock, JSValue baseValue, JSValue index, StructureStubInfo& stubInfo)
{
if (!baseValue.isCell())
return GiveUpOnCache;
if (!index.isInt32())
return RetryCacheLater;
VM& vm = globalObject->vm();
AccessGenerationResult result;
{
GCSafeConcurrentJSLocker locker(codeBlock->m_lock, globalObject->vm().heap);
JSCell* base = baseValue.asCell();
AccessCase::AccessType accessType;
if (base->type() == DirectArgumentsType)
accessType = AccessCase::IndexedDirectArgumentsLoad;
else if (base->type() == ScopedArgumentsType)
accessType = AccessCase::IndexedScopedArgumentsLoad;
else if (base->type() == StringType)
accessType = AccessCase::IndexedStringLoad;
else if (isTypedView(base->classInfo(vm)->typedArrayStorageType)) {
switch (base->classInfo(vm)->typedArrayStorageType) {
case TypeInt8:
accessType = AccessCase::IndexedTypedArrayInt8Load;
break;
case TypeUint8:
accessType = AccessCase::IndexedTypedArrayUint8Load;
break;
case TypeUint8Clamped:
accessType = AccessCase::IndexedTypedArrayUint8ClampedLoad;
break;
case TypeInt16:
accessType = AccessCase::IndexedTypedArrayInt16Load;
break;
case TypeUint16:
accessType = AccessCase::IndexedTypedArrayUint16Load;
break;
case TypeInt32:
accessType = AccessCase::IndexedTypedArrayInt32Load;
break;
case TypeUint32:
accessType = AccessCase::IndexedTypedArrayUint32Load;
break;
case TypeFloat32:
accessType = AccessCase::IndexedTypedArrayFloat32Load;
break;
case TypeFloat64:
accessType = AccessCase::IndexedTypedArrayFloat64Load;
break;
default:
RELEASE_ASSERT_NOT_REACHED();
}
} else {
IndexingType indexingShape = base->indexingType() & IndexingShapeMask;
switch (indexingShape) {
case Int32Shape:
accessType = AccessCase::IndexedInt32Load;
break;
case DoubleShape:
accessType = AccessCase::IndexedDoubleLoad;
break;
case ContiguousShape:
accessType = AccessCase::IndexedContiguousLoad;
break;
case ArrayStorageShape:
accessType = AccessCase::IndexedArrayStorageLoad;
break;
default:
return GiveUpOnCache;
}
}
result = stubInfo.addAccessCase(locker, codeBlock, nullptr, AccessCase::create(vm, codeBlock, accessType, nullptr));
if (result.generatedSomeCode()) {
LOG_IC((ICEvent::GetByReplaceWithJump, baseValue.classInfoOrNull(vm), Identifier()));
RELEASE_ASSERT(result.code());
InlineAccess::rewireStubAsJump(stubInfo, CodeLocationLabel<JITStubRoutinePtrTag>(result.code()));
}
}
fireWatchpointsAndClearStubIfNeeded(vm, stubInfo, codeBlock, result);
return result.shouldGiveUpNow() ? GiveUpOnCache : RetryCacheLater;
}
void repatchArrayGetByVal(JSGlobalObject* globalObject, CodeBlock* codeBlock, JSValue base, JSValue index, StructureStubInfo& stubInfo)
{
if (tryCacheArrayGetByVal(globalObject, codeBlock, base, index, stubInfo) == GiveUpOnCache)
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, operationGetByValGeneric);
}
static V_JITOperation_GSsiJJI appropriateGenericPutByIdFunction(const PutPropertySlot &slot, PutKind putKind)
{
if (slot.isStrictMode()) {
if (putKind == Direct)
return operationPutByIdDirectStrict;
return operationPutByIdStrict;
}
if (putKind == Direct)
return operationPutByIdDirectNonStrict;
return operationPutByIdNonStrict;
}
static V_JITOperation_GSsiJJI appropriateOptimizingPutByIdFunction(const PutPropertySlot &slot, PutKind putKind)
{
if (slot.isStrictMode()) {
if (putKind == Direct)
return operationPutByIdDirectStrictOptimize;
return operationPutByIdStrictOptimize;
}
if (putKind == Direct)
return operationPutByIdDirectNonStrictOptimize;
return operationPutByIdNonStrictOptimize;
}
static InlineCacheAction tryCachePutByID(JSGlobalObject* globalObject, CodeBlock* codeBlock, JSValue baseValue, Structure* structure, const Identifier& ident, const PutPropertySlot& slot, StructureStubInfo& stubInfo, PutKind putKind)
{
VM& vm = globalObject->vm();
AccessGenerationResult result;
{
GCSafeConcurrentJSLocker locker(codeBlock->m_lock, globalObject->vm().heap);
if (forceICFailure(globalObject))
return GiveUpOnCache;
if (!baseValue.isCell())
return GiveUpOnCache;
if (!slot.isCacheablePut() && !slot.isCacheableCustom() && !slot.isCacheableSetter())
return GiveUpOnCache;
// FIXME: We should try to do something smarter here...
if (isCopyOnWrite(structure->indexingMode()))
return GiveUpOnCache;
// We can't end up storing to a CoW on the prototype since it shouldn't own properties.
ASSERT(!isCopyOnWrite(slot.base()->indexingMode()));
if (!structure->propertyAccessesAreCacheable())
return GiveUpOnCache;
std::unique_ptr<AccessCase> newCase;
JSCell* baseCell = baseValue.asCell();
if (slot.base() == baseValue && slot.isCacheablePut()) {
if (slot.type() == PutPropertySlot::ExistingProperty) {
// This assert helps catch bugs if we accidentally forget to disable caching
// when we transition then store to an existing property. This is common among
// paths that reify lazy properties. If we reify a lazy property and forget
// to disable caching, we may come down this path. The Replace IC does not
// know how to model these types of structure transitions (or any structure
// transition for that matter).
RELEASE_ASSERT(baseValue.asCell()->structure(vm) == structure);
structure->didCachePropertyReplacement(vm, slot.cachedOffset());
if (stubInfo.cacheType() == CacheType::Unset
&& InlineAccess::canGenerateSelfPropertyReplace(stubInfo, slot.cachedOffset())
&& !structure->needImpurePropertyWatchpoint()) {
bool generatedCodeInline = InlineAccess::generateSelfPropertyReplace(stubInfo, structure, slot.cachedOffset());
if (generatedCodeInline) {
LOG_IC((ICEvent::PutByIdSelfPatch, structure->classInfo(), ident, slot.base() == baseValue));
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, appropriateOptimizingPutByIdFunction(slot, putKind));
stubInfo.initPutByIdReplace(codeBlock, structure, slot.cachedOffset());
return RetryCacheLater;
}
}
newCase = AccessCase::create(vm, codeBlock, AccessCase::Replace, ident, slot.cachedOffset(), structure);
} else {
ASSERT(slot.type() == PutPropertySlot::NewProperty);
if (!structure->isObject())
return GiveUpOnCache;
if (structure->isDictionary()) {
if (structure->hasBeenFlattenedBefore())
return GiveUpOnCache;
structure->flattenDictionaryStructure(vm, jsCast<JSObject*>(baseValue));
return RetryCacheLater;
}
PropertyOffset offset;
Structure* newStructure = Structure::addPropertyTransitionToExistingStructureConcurrently(structure, ident.impl(), static_cast<unsigned>(PropertyAttribute::None), offset);
if (!newStructure || !newStructure->propertyAccessesAreCacheable())
return GiveUpOnCache;
ASSERT(newStructure->previousID() == structure);
ASSERT(!newStructure->isDictionary());
ASSERT(newStructure->isObject());
std::unique_ptr<PolyProtoAccessChain> prototypeAccessChain;
ObjectPropertyConditionSet conditionSet;
if (putKind == NotDirect) {
auto cacheStatus = prepareChainForCaching(globalObject, baseCell, nullptr);
if (!cacheStatus)
return GiveUpOnCache;
if (cacheStatus->usesPolyProto) {
prototypeAccessChain = PolyProtoAccessChain::create(globalObject, baseCell, nullptr);
if (!prototypeAccessChain)
return GiveUpOnCache;
} else {
prototypeAccessChain = nullptr;
conditionSet = generateConditionsForPropertySetterMiss(
vm, codeBlock, globalObject, newStructure, ident.impl());
if (!conditionSet.isValid())
return GiveUpOnCache;
}
}
newCase = AccessCase::create(vm, codeBlock, ident, offset, structure, newStructure, conditionSet, WTFMove(prototypeAccessChain));
}
} else if (slot.isCacheableCustom() || slot.isCacheableSetter()) {
if (slot.isCacheableCustom()) {
ObjectPropertyConditionSet conditionSet;
std::unique_ptr<PolyProtoAccessChain> prototypeAccessChain;
// We need to do this even if we're a self custom, since we must disallow dictionaries
// because we need to be informed if the custom goes away since we cache the constant
// function pointer.
auto cacheStatus = prepareChainForCaching(globalObject, baseCell, slot.base());
if (!cacheStatus)
return GiveUpOnCache;
if (slot.base() != baseValue) {
if (cacheStatus->usesPolyProto) {
prototypeAccessChain = PolyProtoAccessChain::create(globalObject, baseCell, slot.base());
if (!prototypeAccessChain)
return GiveUpOnCache;
} else {
prototypeAccessChain = nullptr;
conditionSet = generateConditionsForPrototypePropertyHitCustom(
vm, codeBlock, globalObject, structure, slot.base(), ident.impl(), static_cast<unsigned>(PropertyAttribute::None));
if (!conditionSet.isValid())
return GiveUpOnCache;
}
}
newCase = GetterSetterAccessCase::create(
vm, codeBlock, slot.isCustomAccessor() ? AccessCase::CustomAccessorSetter : AccessCase::CustomValueSetter, structure, ident,
invalidOffset, conditionSet, WTFMove(prototypeAccessChain), slot.customSetter(), slot.base() != baseValue ? slot.base() : nullptr);
} else {
ObjectPropertyConditionSet conditionSet;
std::unique_ptr<PolyProtoAccessChain> prototypeAccessChain;
PropertyOffset offset = slot.cachedOffset();
if (slot.base() != baseValue) {
auto cacheStatus = prepareChainForCaching(globalObject, baseCell, slot.base());
if (!cacheStatus)
return GiveUpOnCache;
if (cacheStatus->flattenedDictionary)
return RetryCacheLater;
if (cacheStatus->usesPolyProto) {
prototypeAccessChain = PolyProtoAccessChain::create(globalObject, baseCell, slot.base());
if (!prototypeAccessChain)
return GiveUpOnCache;
offset = prototypeAccessChain->slotBaseStructure(baseCell->structure(vm))->get(vm, ident.impl());
} else {
prototypeAccessChain = nullptr;
conditionSet = generateConditionsForPrototypePropertyHit(
vm, codeBlock, globalObject, structure, slot.base(), ident.impl());
if (!conditionSet.isValid())
return GiveUpOnCache;
if (!(conditionSet.slotBaseCondition().attributes() & PropertyAttribute::Accessor))
return GiveUpOnCache;
offset = conditionSet.slotBaseCondition().offset();
}
}
newCase = GetterSetterAccessCase::create(
vm, codeBlock, AccessCase::Setter, structure, ident, offset, conditionSet, WTFMove(prototypeAccessChain));
}
}
LOG_IC((ICEvent::PutByIdAddAccessCase, structure->classInfo(), ident, slot.base() == baseValue));
result = stubInfo.addAccessCase(locker, codeBlock, ident, WTFMove(newCase));
if (result.generatedSomeCode()) {
LOG_IC((ICEvent::PutByIdReplaceWithJump, structure->classInfo(), ident, slot.base() == baseValue));
RELEASE_ASSERT(result.code());
InlineAccess::rewireStubAsJump(stubInfo, CodeLocationLabel<JITStubRoutinePtrTag>(result.code()));
}
}
fireWatchpointsAndClearStubIfNeeded(vm, stubInfo, codeBlock, result);
return result.shouldGiveUpNow() ? GiveUpOnCache : RetryCacheLater;
}
void repatchPutByID(JSGlobalObject* globalObject, CodeBlock* codeBlock, JSValue baseValue, Structure* structure, const Identifier& propertyName, const PutPropertySlot& slot, StructureStubInfo& stubInfo, PutKind putKind)
{
SuperSamplerScope superSamplerScope(false);
if (tryCachePutByID(globalObject, codeBlock, baseValue, structure, propertyName, slot, stubInfo, putKind) == GiveUpOnCache)
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, appropriateGenericPutByIdFunction(slot, putKind));
}
static InlineCacheAction tryCacheInByID(
JSGlobalObject* globalObject, CodeBlock* codeBlock, JSObject* base, const Identifier& ident,
bool wasFound, const PropertySlot& slot, StructureStubInfo& stubInfo)
{
VM& vm = globalObject->vm();
AccessGenerationResult result;
{
GCSafeConcurrentJSLocker locker(codeBlock->m_lock, vm.heap);
if (forceICFailure(globalObject))
return GiveUpOnCache;
if (!base->structure(vm)->propertyAccessesAreCacheable() || (!wasFound && !base->structure(vm)->propertyAccessesAreCacheableForAbsence()))
return GiveUpOnCache;
if (wasFound) {
if (!slot.isCacheable())
return GiveUpOnCache;
}
Structure* structure = base->structure(vm);
std::unique_ptr<PolyProtoAccessChain> prototypeAccessChain;
ObjectPropertyConditionSet conditionSet;
if (wasFound) {
InlineCacheAction action = actionForCell(vm, base);
if (action != AttemptToCache)
return action;
// Optimize self access.
if (stubInfo.cacheType() == CacheType::Unset
&& slot.isCacheableValue()
&& slot.slotBase() == base
&& !slot.watchpointSet()
&& !structure->needImpurePropertyWatchpoint()) {
bool generatedCodeInline = InlineAccess::generateSelfInAccess(stubInfo, structure);
if (generatedCodeInline) {
LOG_IC((ICEvent::InByIdSelfPatch, structure->classInfo(), ident, slot.slotBase() == base));
structure->startWatchingPropertyForReplacements(vm, slot.cachedOffset());
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, operationInByIdOptimize);
stubInfo.initInByIdSelf(codeBlock, structure, slot.cachedOffset());
return RetryCacheLater;
}
}
if (slot.slotBase() != base) {
auto cacheStatus = prepareChainForCaching(globalObject, base, slot);
if (!cacheStatus)
return GiveUpOnCache;
if (cacheStatus->flattenedDictionary)
return RetryCacheLater;
if (cacheStatus->usesPolyProto) {
prototypeAccessChain = PolyProtoAccessChain::create(globalObject, base, slot);
if (!prototypeAccessChain)
return GiveUpOnCache;
RELEASE_ASSERT(slot.isCacheableCustom() || prototypeAccessChain->slotBaseStructure(structure)->get(vm, ident.impl()) == slot.cachedOffset());
} else {
prototypeAccessChain = nullptr;
conditionSet = generateConditionsForPrototypePropertyHit(
vm, codeBlock, globalObject, structure, slot.slotBase(), ident.impl());
if (!conditionSet.isValid())
return GiveUpOnCache;
RELEASE_ASSERT(slot.isCacheableCustom() || conditionSet.slotBaseCondition().offset() == slot.cachedOffset());
}
}
} else {
auto cacheStatus = prepareChainForCaching(globalObject, base, nullptr);
if (!cacheStatus)
return GiveUpOnCache;
if (cacheStatus->usesPolyProto) {
prototypeAccessChain = PolyProtoAccessChain::create(globalObject, base, slot);
if (!prototypeAccessChain)
return GiveUpOnCache;
} else {
prototypeAccessChain = nullptr;
conditionSet = generateConditionsForPropertyMiss(
vm, codeBlock, globalObject, structure, ident.impl());
if (!conditionSet.isValid())
return GiveUpOnCache;
}
}
LOG_IC((ICEvent::InAddAccessCase, structure->classInfo(), ident, slot.slotBase() == base));
std::unique_ptr<AccessCase> newCase = AccessCase::create(
vm, codeBlock, wasFound ? AccessCase::InHit : AccessCase::InMiss, ident, wasFound ? slot.cachedOffset() : invalidOffset, structure, conditionSet, WTFMove(prototypeAccessChain));
result = stubInfo.addAccessCase(locker, codeBlock, ident, WTFMove(newCase));
if (result.generatedSomeCode()) {
LOG_IC((ICEvent::InReplaceWithJump, structure->classInfo(), ident, slot.slotBase() == base));
RELEASE_ASSERT(result.code());
InlineAccess::rewireStubAsJump(stubInfo, CodeLocationLabel<JITStubRoutinePtrTag>(result.code()));
}
}
fireWatchpointsAndClearStubIfNeeded(vm, stubInfo, codeBlock, result);
return result.shouldGiveUpNow() ? GiveUpOnCache : RetryCacheLater;
}
void repatchInByID(JSGlobalObject* globalObject, CodeBlock* codeBlock, JSObject* baseObject, const Identifier& propertyName, bool wasFound, const PropertySlot& slot, StructureStubInfo& stubInfo)
{
SuperSamplerScope superSamplerScope(false);
if (tryCacheInByID(globalObject, codeBlock, baseObject, propertyName, wasFound, slot, stubInfo) == GiveUpOnCache)
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, operationInById);
}
static InlineCacheAction tryCacheInstanceOf(
JSGlobalObject* globalObject, CodeBlock* codeBlock, JSValue valueValue, JSValue prototypeValue, StructureStubInfo& stubInfo,
bool wasFound)
{
VM& vm = globalObject->vm();
AccessGenerationResult result;
RELEASE_ASSERT(valueValue.isCell()); // shouldConsiderCaching rejects non-cells.
if (forceICFailure(globalObject))
return GiveUpOnCache;
{
GCSafeConcurrentJSLocker locker(codeBlock->m_lock, vm.heap);
JSCell* value = valueValue.asCell();
Structure* structure = value->structure(vm);
std::unique_ptr<AccessCase> newCase;
JSObject* prototype = jsDynamicCast<JSObject*>(vm, prototypeValue);
if (prototype) {
if (!jsDynamicCast<JSObject*>(vm, value)) {
newCase = InstanceOfAccessCase::create(
vm, codeBlock, AccessCase::InstanceOfMiss, structure, ObjectPropertyConditionSet(),
prototype);
} else if (structure->prototypeQueriesAreCacheable()) {
// FIXME: Teach this to do poly proto.
// https://bugs.webkit.org/show_bug.cgi?id=185663
prepareChainForCaching(globalObject, value, wasFound ? prototype : nullptr);
ObjectPropertyConditionSet conditionSet = generateConditionsForInstanceOf(
vm, codeBlock, globalObject, structure, prototype, wasFound);
if (conditionSet.isValid()) {
newCase = InstanceOfAccessCase::create(
vm, codeBlock,
wasFound ? AccessCase::InstanceOfHit : AccessCase::InstanceOfMiss,
structure, conditionSet, prototype);
}
}
}
if (!newCase)
newCase = AccessCase::create(vm, codeBlock, AccessCase::InstanceOfGeneric, Identifier());
LOG_IC((ICEvent::InstanceOfAddAccessCase, structure->classInfo(), Identifier()));
result = stubInfo.addAccessCase(locker, codeBlock, nullptr, WTFMove(newCase));
if (result.generatedSomeCode()) {
LOG_IC((ICEvent::InstanceOfReplaceWithJump, structure->classInfo(), Identifier()));
RELEASE_ASSERT(result.code());
MacroAssembler::repatchJump(
stubInfo.patchableJump(),
CodeLocationLabel<JITStubRoutinePtrTag>(result.code()));
}
}
fireWatchpointsAndClearStubIfNeeded(vm, stubInfo, codeBlock, result);
return result.shouldGiveUpNow() ? GiveUpOnCache : RetryCacheLater;
}
void repatchInstanceOf(
JSGlobalObject* globalObject, CodeBlock* codeBlock, JSValue valueValue, JSValue prototypeValue, StructureStubInfo& stubInfo,
bool wasFound)
{
SuperSamplerScope superSamplerScope(false);
if (tryCacheInstanceOf(globalObject, codeBlock, valueValue, prototypeValue, stubInfo, wasFound) == GiveUpOnCache)
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, operationInstanceOfGeneric);
}
static void linkSlowFor(VM&, CallLinkInfo& callLinkInfo, MacroAssemblerCodeRef<JITStubRoutinePtrTag> codeRef)
{
MacroAssembler::repatchNearCall(callLinkInfo.callReturnLocation(), CodeLocationLabel<JITStubRoutinePtrTag>(codeRef.code()));
}
static void linkSlowFor(VM& vm, CallLinkInfo& callLinkInfo, ThunkGenerator generator)
{
linkSlowFor(vm, callLinkInfo, vm.getCTIStub(generator).retagged<JITStubRoutinePtrTag>());
}
static void linkSlowFor(VM& vm, CallLinkInfo& callLinkInfo)
{
MacroAssemblerCodeRef<JITStubRoutinePtrTag> virtualThunk = virtualThunkFor(vm, callLinkInfo);
linkSlowFor(vm, callLinkInfo, virtualThunk);
callLinkInfo.setSlowStub(GCAwareJITStubRoutine::create(virtualThunk, vm));
}
static JSCell* webAssemblyOwner(JSCell* callee)
{
#if ENABLE(WEBASSEMBLY)
// Each WebAssembly.Instance shares the stubs from their WebAssembly.Module, which are therefore the appropriate owner.
return jsCast<JSWebAssemblyModule*>(callee);
#else
UNUSED_PARAM(callee);
RELEASE_ASSERT_NOT_REACHED();
return nullptr;
#endif // ENABLE(WEBASSEMBLY)
}
void linkFor(
VM& vm, CallFrame* callFrame, CallLinkInfo& callLinkInfo, CodeBlock* calleeCodeBlock,
JSObject* callee, MacroAssemblerCodePtr<JSEntryPtrTag> codePtr)
{
ASSERT(!callLinkInfo.stub());
CallFrame* callerFrame = callFrame->callerFrame();
// Our caller must have a cell for a callee. When calling
// this from Wasm, we ensure the callee is a cell.
ASSERT(callerFrame->callee().isCell());
CodeBlock* callerCodeBlock = callerFrame->codeBlock();
// WebAssembly -> JS stubs don't have a valid CodeBlock.
JSCell* owner = isWebAssemblyModule(callerFrame->callee().asCell()) ? webAssemblyOwner(callerFrame->callee().asCell()) : callerCodeBlock;
ASSERT(owner);
ASSERT(!callLinkInfo.isLinked());
callLinkInfo.setCallee(vm, owner, callee);
MacroAssembler::repatchPointer(callLinkInfo.hotPathBegin(), callee);
callLinkInfo.setLastSeenCallee(vm, owner, callee);
if (shouldDumpDisassemblyFor(callerCodeBlock))
dataLog("Linking call in ", FullCodeOrigin(callerCodeBlock, callLinkInfo.codeOrigin()), " to ", pointerDump(calleeCodeBlock), ", entrypoint at ", codePtr, "\n");
MacroAssembler::repatchNearCall(callLinkInfo.hotPathOther(), CodeLocationLabel<JSEntryPtrTag>(codePtr));
if (calleeCodeBlock)
calleeCodeBlock->linkIncomingCall(callerFrame, &callLinkInfo);
if (callLinkInfo.specializationKind() == CodeForCall && callLinkInfo.allowStubs()) {
linkSlowFor(vm, callLinkInfo, linkPolymorphicCallThunkGenerator);
return;
}
linkSlowFor(vm, callLinkInfo);
}
void linkDirectFor(
CallFrame* callFrame, CallLinkInfo& callLinkInfo, CodeBlock* calleeCodeBlock,
MacroAssemblerCodePtr<JSEntryPtrTag> codePtr)
{
ASSERT(!callLinkInfo.stub());
CodeBlock* callerCodeBlock = callFrame->codeBlock();
VM& vm = callerCodeBlock->vm();
ASSERT(!callLinkInfo.isLinked());
callLinkInfo.setCodeBlock(vm, callerCodeBlock, jsCast<FunctionCodeBlock*>(calleeCodeBlock));
if (shouldDumpDisassemblyFor(callerCodeBlock))
dataLog("Linking call in ", FullCodeOrigin(callerCodeBlock, callLinkInfo.codeOrigin()), " to ", pointerDump(calleeCodeBlock), ", entrypoint at ", codePtr, "\n");
if (callLinkInfo.callType() == CallLinkInfo::DirectTailCall)
MacroAssembler::repatchJumpToNop(callLinkInfo.patchableJump());
MacroAssembler::repatchNearCall(callLinkInfo.hotPathOther(), CodeLocationLabel<JSEntryPtrTag>(codePtr));
if (calleeCodeBlock)
calleeCodeBlock->linkIncomingCall(callFrame, &callLinkInfo);
}
void linkSlowFor(CallFrame* callFrame, CallLinkInfo& callLinkInfo)
{
CodeBlock* callerCodeBlock = callFrame->callerFrame()->codeBlock();
VM& vm = callerCodeBlock->vm();
linkSlowFor(vm, callLinkInfo);
}
static void revertCall(VM& vm, CallLinkInfo& callLinkInfo, MacroAssemblerCodeRef<JITStubRoutinePtrTag> codeRef)
{
if (callLinkInfo.isDirect()) {
callLinkInfo.clearCodeBlock();
if (!callLinkInfo.clearedByJettison()) {
if (callLinkInfo.callType() == CallLinkInfo::DirectTailCall)
MacroAssembler::repatchJump(callLinkInfo.patchableJump(), callLinkInfo.slowPathStart());
else
MacroAssembler::repatchNearCall(callLinkInfo.hotPathOther(), callLinkInfo.slowPathStart());
}
} else {
if (!callLinkInfo.clearedByJettison()) {
MacroAssembler::revertJumpReplacementToBranchPtrWithPatch(
MacroAssembler::startOfBranchPtrWithPatchOnRegister(callLinkInfo.hotPathBegin()),
callLinkInfo.calleeGPR(), 0);
linkSlowFor(vm, callLinkInfo, codeRef);
MacroAssembler::repatchPointer(callLinkInfo.hotPathBegin(), nullptr);
}
callLinkInfo.clearCallee();
}
callLinkInfo.clearSeen();
callLinkInfo.clearStub();
callLinkInfo.clearSlowStub();
if (callLinkInfo.isOnList())
callLinkInfo.remove();
}
void unlinkFor(VM& vm, CallLinkInfo& callLinkInfo)
{
dataLogLnIf(Options::dumpDisassembly(), "Unlinking call at ", callLinkInfo.hotPathOther());
revertCall(vm, callLinkInfo, vm.getCTIStub(linkCallThunkGenerator).retagged<JITStubRoutinePtrTag>());
}
static void linkVirtualFor(VM& vm, CallFrame* callFrame, CallLinkInfo& callLinkInfo)
{
CallFrame* callerFrame = callFrame->callerFrame();
CodeBlock* callerCodeBlock = callerFrame->codeBlock();
dataLogLnIf(shouldDumpDisassemblyFor(callerCodeBlock),
"Linking virtual call at ", FullCodeOrigin(callerCodeBlock, callerFrame->codeOrigin()));
MacroAssemblerCodeRef<JITStubRoutinePtrTag> virtualThunk = virtualThunkFor(vm, callLinkInfo);
revertCall(vm, callLinkInfo, virtualThunk);
callLinkInfo.setSlowStub(GCAwareJITStubRoutine::create(virtualThunk, vm));
callLinkInfo.setClearedByVirtual();
}
namespace {
struct CallToCodePtr {
CCallHelpers::Call call;
MacroAssemblerCodePtr<JSEntryPtrTag> codePtr;
};
} // annonymous namespace
void linkPolymorphicCall(JSGlobalObject* globalObject, CallFrame* callFrame, CallLinkInfo& callLinkInfo, CallVariant newVariant)
{
RELEASE_ASSERT(callLinkInfo.allowStubs());
CallFrame* callerFrame = callFrame->callerFrame();
VM& vm = globalObject->vm();
// During execution of linkPolymorphicCall, we strongly assume that we never do GC.
// GC jettisons CodeBlocks, changes CallLinkInfo etc. and breaks assumption done before and after this call.
DeferGCForAWhile deferGCForAWhile(vm.heap);
if (!newVariant) {
linkVirtualFor(vm, callFrame, callLinkInfo);
return;
}
// Our caller must be have a cell for a callee. When calling
// this from Wasm, we ensure the callee is a cell.
ASSERT(callerFrame->callee().isCell());
CodeBlock* callerCodeBlock = callerFrame->codeBlock();
bool isWebAssembly = isWebAssemblyModule(callerFrame->callee().asCell());
// WebAssembly -> JS stubs don't have a valid CodeBlock.
JSCell* owner = isWebAssembly ? webAssemblyOwner(callerFrame->callee().asCell()) : callerCodeBlock;
ASSERT(owner);
CallVariantList list;
if (PolymorphicCallStubRoutine* stub = callLinkInfo.stub())
list = stub->variants();
else if (JSObject* oldCallee = callLinkInfo.callee())
list = CallVariantList { CallVariant(oldCallee) };
list = variantListWithVariant(list, newVariant);
// If there are any closure calls then it makes sense to treat all of them as closure calls.
// This makes switching on callee cheaper. It also produces profiling that's easier on the DFG;
// the DFG doesn't really want to deal with a combination of closure and non-closure callees.
bool isClosureCall = false;
for (CallVariant variant : list) {
if (variant.isClosureCall()) {
list = despecifiedVariantList(list);
isClosureCall = true;
break;
}
}
if (isClosureCall)
callLinkInfo.setHasSeenClosure();
Vector<PolymorphicCallCase> callCases;
Vector<int64_t> caseValues;
// Figure out what our cases are.
for (CallVariant variant : list) {
CodeBlock* codeBlock = nullptr;
if (variant.executable() && !variant.executable()->isHostFunction()) {
ExecutableBase* executable = variant.executable();
codeBlock = jsCast<FunctionExecutable*>(executable)->codeBlockForCall();
// If we cannot handle a callee, either because we don't have a CodeBlock or because arity mismatch,
// assume that it's better for this whole thing to be a virtual call.
if (!codeBlock || callFrame->argumentCountIncludingThis() < static_cast<size_t>(codeBlock->numParameters()) || callLinkInfo.isVarargs()) {
linkVirtualFor(vm, callFrame, callLinkInfo);
return;
}
}
int64_t newCaseValue = 0;
if (isClosureCall) {
newCaseValue = bitwise_cast<intptr_t>(variant.executable());
// FIXME: We could add a fast path for InternalFunction with closure call.
// https://bugs.webkit.org/show_bug.cgi?id=179311
if (!newCaseValue)
continue;
} else {
if (auto* function = variant.function())
newCaseValue = bitwise_cast<intptr_t>(function);
else
newCaseValue = bitwise_cast<intptr_t>(variant.internalFunction());
}
if (ASSERT_ENABLED) {
if (caseValues.contains(newCaseValue)) {
dataLog("ERROR: Attempt to add duplicate case value.\n");
dataLog("Existing case values: ");
CommaPrinter comma;
for (auto& value : caseValues)
dataLog(comma, value);
dataLog("\n");
dataLog("Attempting to add: ", newCaseValue, "\n");
dataLog("Variant list: ", listDump(callCases), "\n");
RELEASE_ASSERT_NOT_REACHED();
}
}
callCases.append(PolymorphicCallCase(variant, codeBlock));
caseValues.append(newCaseValue);
}
ASSERT(callCases.size() == caseValues.size());
// If we are over the limit, just use a normal virtual call.
unsigned maxPolymorphicCallVariantListSize;
if (isWebAssembly)
maxPolymorphicCallVariantListSize = Options::maxPolymorphicCallVariantListSizeForWebAssemblyToJS();
else if (callerCodeBlock->jitType() == JITCode::topTierJIT())
maxPolymorphicCallVariantListSize = Options::maxPolymorphicCallVariantListSizeForTopTier();
else
maxPolymorphicCallVariantListSize = Options::maxPolymorphicCallVariantListSize();
// We use list.size() instead of callCases.size() because we respect CallVariant size for now.
if (list.size() > maxPolymorphicCallVariantListSize) {
linkVirtualFor(vm, callFrame, callLinkInfo);
return;
}
Vector<CallToCodePtr> calls(callCases.size());
UniqueArray<uint32_t> fastCounts;
if (!isWebAssembly && callerCodeBlock->jitType() != JITCode::topTierJIT()) {
fastCounts = makeUniqueArray<uint32_t>(callCases.size());
memset(fastCounts.get(), 0, callCases.size() * sizeof(uint32_t));
}
GPRReg calleeGPR = callLinkInfo.calleeGPR();
CCallHelpers stubJit(callerCodeBlock);
std::unique_ptr<CallFrameShuffler> frameShuffler;
if (callLinkInfo.frameShuffleData()) {
ASSERT(callLinkInfo.isTailCall());
frameShuffler = makeUnique<CallFrameShuffler>(stubJit, *callLinkInfo.frameShuffleData());
#if USE(JSVALUE32_64)
// We would have already checked that the callee is a cell, and we can
// use the additional register this buys us.
frameShuffler->assumeCalleeIsCell();
#endif
frameShuffler->lockGPR(calleeGPR);
}
GPRReg comparisonValueGPR;
if (isClosureCall) {
if (frameShuffler)
comparisonValueGPR = frameShuffler->acquireGPR();
else
comparisonValueGPR = AssemblyHelpers::selectScratchGPR(calleeGPR);
} else
comparisonValueGPR = calleeGPR;
GPRReg fastCountsBaseGPR;
if (frameShuffler)
fastCountsBaseGPR = frameShuffler->acquireGPR();
else {
fastCountsBaseGPR =
AssemblyHelpers::selectScratchGPR(calleeGPR, comparisonValueGPR, GPRInfo::regT3);
}
stubJit.move(CCallHelpers::TrustedImmPtr(fastCounts.get()), fastCountsBaseGPR);
if (!frameShuffler && callLinkInfo.isTailCall()) {
// We strongly assume that calleeGPR is not a callee save register in the slow path.
ASSERT(!callerCodeBlock->calleeSaveRegisters()->find(calleeGPR));
stubJit.emitRestoreCalleeSaves();
}
CCallHelpers::JumpList slowPath;
if (isClosureCall) {
// Verify that we have a function and stash the executable in scratchGPR.
#if USE(JSVALUE64)
if (callLinkInfo.isTailCall())
slowPath.append(stubJit.branchIfNotCell(calleeGPR, DoNotHaveTagRegisters));
else
slowPath.append(stubJit.branchIfNotCell(calleeGPR));
#else
// We would have already checked that the callee is a cell.
#endif
// FIXME: We could add a fast path for InternalFunction with closure call.
slowPath.append(stubJit.branchIfNotFunction(calleeGPR));
stubJit.loadPtr(CCallHelpers::Address(calleeGPR, JSFunction::offsetOfExecutableOrRareData()), comparisonValueGPR);
auto hasExecutable = stubJit.branchTestPtr(CCallHelpers::Zero, comparisonValueGPR, CCallHelpers::TrustedImm32(JSFunction::rareDataTag));
stubJit.loadPtr(CCallHelpers::Address(comparisonValueGPR, FunctionRareData::offsetOfExecutable() - JSFunction::rareDataTag), comparisonValueGPR);
hasExecutable.link(&stubJit);
}
BinarySwitch binarySwitch(comparisonValueGPR, caseValues, BinarySwitch::IntPtr);
CCallHelpers::JumpList done;
while (binarySwitch.advance(stubJit)) {
size_t caseIndex = binarySwitch.caseIndex();
CallVariant variant = callCases[caseIndex].variant();
MacroAssemblerCodePtr<JSEntryPtrTag> codePtr;
if (variant.executable()) {
ASSERT(variant.executable()->hasJITCodeForCall());
codePtr = jsToWasmICCodePtr(vm, callLinkInfo.specializationKind(), variant.function());
if (!codePtr)
codePtr = variant.executable()->generatedJITCodeForCall()->addressForCall(ArityCheckNotRequired);
} else {
ASSERT(variant.internalFunction());
codePtr = vm.getCTIInternalFunctionTrampolineFor(CodeForCall);
}
if (fastCounts) {
stubJit.add32(
CCallHelpers::TrustedImm32(1),
CCallHelpers::Address(fastCountsBaseGPR, caseIndex * sizeof(uint32_t)));
}
if (frameShuffler) {
CallFrameShuffler(stubJit, frameShuffler->snapshot()).prepareForTailCall();
calls[caseIndex].call = stubJit.nearTailCall();
} else if (callLinkInfo.isTailCall()) {
stubJit.prepareForTailCallSlow();
calls[caseIndex].call = stubJit.nearTailCall();
} else
calls[caseIndex].call = stubJit.nearCall();
calls[caseIndex].codePtr = codePtr;
done.append(stubJit.jump());
}
slowPath.link(&stubJit);
binarySwitch.fallThrough().link(&stubJit);
if (frameShuffler) {
frameShuffler->releaseGPR(calleeGPR);
frameShuffler->releaseGPR(comparisonValueGPR);
frameShuffler->releaseGPR(fastCountsBaseGPR);
#if USE(JSVALUE32_64)
frameShuffler->setCalleeJSValueRegs(JSValueRegs(GPRInfo::regT1, GPRInfo::regT0));
#else
frameShuffler->setCalleeJSValueRegs(JSValueRegs(GPRInfo::regT0));
#endif
frameShuffler->prepareForSlowPath();
} else {
stubJit.move(calleeGPR, GPRInfo::regT0);
#if USE(JSVALUE32_64)
stubJit.move(CCallHelpers::TrustedImm32(JSValue::CellTag), GPRInfo::regT1);
#endif
}
stubJit.move(CCallHelpers::TrustedImmPtr(globalObject), GPRInfo::regT3);
stubJit.move(CCallHelpers::TrustedImmPtr(&callLinkInfo), GPRInfo::regT2);
stubJit.move(CCallHelpers::TrustedImmPtr(callLinkInfo.callReturnLocation().untaggedExecutableAddress()), GPRInfo::regT4);
stubJit.restoreReturnAddressBeforeReturn(GPRInfo::regT4);
AssemblyHelpers::Jump slow = stubJit.jump();
LinkBuffer patchBuffer(stubJit, owner, JITCompilationCanFail);
if (patchBuffer.didFailToAllocate()) {
linkVirtualFor(vm, callFrame, callLinkInfo);
return;
}
RELEASE_ASSERT(callCases.size() == calls.size());
for (CallToCodePtr callToCodePtr : calls) {
#if CPU(ARM_THUMB2)
// Tail call special-casing ensures proper linking on ARM Thumb2, where a tail call jumps to an address
// with a non-decorated bottom bit but a normal call calls an address with a decorated bottom bit.
bool isTailCall = callToCodePtr.call.isFlagSet(CCallHelpers::Call::Tail);
void* target = isTailCall ? callToCodePtr.codePtr.dataLocation() : callToCodePtr.codePtr.executableAddress();
patchBuffer.link(callToCodePtr.call, FunctionPtr<JSEntryPtrTag>(MacroAssemblerCodePtr<JSEntryPtrTag>::createFromExecutableAddress(target)));
#else
patchBuffer.link(callToCodePtr.call, FunctionPtr<JSEntryPtrTag>(callToCodePtr.codePtr));
#endif
}
if (isWebAssembly || JITCode::isOptimizingJIT(callerCodeBlock->jitType()))
patchBuffer.link(done, callLinkInfo.callReturnLocation().labelAtOffset(0));
else
patchBuffer.link(done, callLinkInfo.hotPathOther().labelAtOffset(0));
patchBuffer.link(slow, CodeLocationLabel<JITThunkPtrTag>(vm.getCTIStub(linkPolymorphicCallThunkGenerator).code()));
auto stubRoutine = adoptRef(*new PolymorphicCallStubRoutine(
FINALIZE_CODE_FOR(
callerCodeBlock, patchBuffer, JITStubRoutinePtrTag,
"Polymorphic call stub for %s, return point %p, targets %s",
isWebAssembly ? "WebAssembly" : toCString(*callerCodeBlock).data(), callLinkInfo.callReturnLocation().labelAtOffset(0).executableAddress(),
toCString(listDump(callCases)).data()),
vm, owner, callFrame->callerFrame(), callLinkInfo, callCases,
WTFMove(fastCounts)));
MacroAssembler::replaceWithJump(
MacroAssembler::startOfBranchPtrWithPatchOnRegister(callLinkInfo.hotPathBegin()),
CodeLocationLabel<JITStubRoutinePtrTag>(stubRoutine->code().code()));
// The original slow path is unreachable on 64-bits, but still
// reachable on 32-bits since a non-cell callee will always
// trigger the slow path
linkSlowFor(vm, callLinkInfo);
// If there had been a previous stub routine, that one will die as soon as the GC runs and sees
// that it's no longer on stack.
callLinkInfo.setStub(WTFMove(stubRoutine));
// The call link info no longer has a call cache apart from the jump to the polymorphic call
// stub.
if (callLinkInfo.isOnList())
callLinkInfo.remove();
}
void resetGetBy(CodeBlock* codeBlock, StructureStubInfo& stubInfo, GetByKind kind)
{
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, appropriateOptimizingGetByFunction(kind));
InlineAccess::rewireStubAsJump(stubInfo, stubInfo.slowPathStartLocation);
}
void resetPutByID(CodeBlock* codeBlock, StructureStubInfo& stubInfo)
{
V_JITOperation_GSsiJJI unoptimizedFunction = reinterpret_cast<V_JITOperation_GSsiJJI>(readPutICCallTarget(codeBlock, stubInfo.slowPathCallLocation).executableAddress());
V_JITOperation_GSsiJJI optimizedFunction;
if (unoptimizedFunction == operationPutByIdStrict || unoptimizedFunction == operationPutByIdStrictOptimize)
optimizedFunction = operationPutByIdStrictOptimize;
else if (unoptimizedFunction == operationPutByIdNonStrict || unoptimizedFunction == operationPutByIdNonStrictOptimize)
optimizedFunction = operationPutByIdNonStrictOptimize;
else if (unoptimizedFunction == operationPutByIdDirectStrict || unoptimizedFunction == operationPutByIdDirectStrictOptimize)
optimizedFunction = operationPutByIdDirectStrictOptimize;
else {
ASSERT(unoptimizedFunction == operationPutByIdDirectNonStrict || unoptimizedFunction == operationPutByIdDirectNonStrictOptimize);
optimizedFunction = operationPutByIdDirectNonStrictOptimize;
}
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, optimizedFunction);
InlineAccess::rewireStubAsJump(stubInfo, stubInfo.slowPathStartLocation);
}
static void resetPatchableJump(StructureStubInfo& stubInfo)
{
MacroAssembler::repatchJump(stubInfo.patchableJump(), stubInfo.slowPathStartLocation);
}
void resetInByID(CodeBlock* codeBlock, StructureStubInfo& stubInfo)
{
ftlThunkAwareRepatchCall(codeBlock, stubInfo.slowPathCallLocation, operationInByIdOptimize);
InlineAccess::rewireStubAsJump(stubInfo, stubInfo.slowPathStartLocation);
}
void resetInstanceOf(StructureStubInfo& stubInfo)
{
resetPatchableJump(stubInfo);
}
MacroAssemblerCodePtr<JSEntryPtrTag> jsToWasmICCodePtr(VM& vm, CodeSpecializationKind kind, JSObject* callee)
{
#if ENABLE(WEBASSEMBLY)
if (!callee)
return nullptr;
if (kind != CodeForCall)
return nullptr;
if (auto* wasmFunction = jsDynamicCast<WebAssemblyFunction*>(vm, callee))
return wasmFunction->jsCallEntrypoint();
#else
UNUSED_PARAM(vm);
UNUSED_PARAM(kind);
UNUSED_PARAM(callee);
#endif
return nullptr;
}
} // namespace JSC
#endif