ClonedArguments* ClonedArguments::createEmpty(
VM& vm, Structure* structure, JSFunction* callee, unsigned length)
{
unsigned vectorLength = length;
if (vectorLength > MAX_STORAGE_VECTOR_LENGTH)
return 0;
Butterfly* butterfly;
if (UNLIKELY(structure->needsSlowPutIndexing())) {
butterfly = createArrayStorageButterfly(vm, nullptr, structure, length, vectorLength);
butterfly->arrayStorage()->m_numValuesInVector = vectorLength;
} else {
void* temp = vm.heap.tryAllocateAuxiliary(nullptr, Butterfly::totalSize(0, structure->outOfLineCapacity(), true, vectorLength * sizeof(EncodedJSValue)));
if (!temp)
return 0;
butterfly = Butterfly::fromBase(temp, 0, structure->outOfLineCapacity());
butterfly->setVectorLength(vectorLength);
butterfly->setPublicLength(length);
for (unsigned i = length; i < vectorLength; ++i)
butterfly->contiguous()[i].clear();
}
ClonedArguments* result =
new (NotNull, allocateCell<ClonedArguments>(vm.heap))
ClonedArguments(vm, structure, butterfly);
result->finishCreation(vm);
result->m_callee.set(vm, result, callee);
result->putDirect(vm, clonedArgumentsLengthPropertyOffset, jsNumber(length));
return result;
}
JSCell* JIT_OPERATION operationCreateClonedArgumentsDuringExit(ExecState* exec, InlineCallFrame* inlineCallFrame, JSFunction* callee, int32_t argumentCount)
{
VM& vm = exec->vm();
NativeCallFrameTracer target(&vm, exec);
DeferGCForAWhile deferGC(vm.heap);
CodeBlock* codeBlock;
if (inlineCallFrame)
codeBlock = baselineCodeBlockForInlineCallFrame(inlineCallFrame);
else
codeBlock = exec->codeBlock();
unsigned length = argumentCount - 1;
ClonedArguments* result = ClonedArguments::createEmpty(
vm, codeBlock->globalObject()->outOfBandArgumentsStructure(), callee);
Register* arguments =
exec->registers() + (inlineCallFrame ? inlineCallFrame->stackOffset : 0) +
CallFrame::argumentOffset(0);
for (unsigned i = length; i--;)
result->putDirectIndex(exec, i, arguments[i].jsValue());
result->putDirect(vm, vm.propertyNames->length, jsNumber(length));
return result;
}
ClonedArguments* ClonedArguments::createByCopyingFrom(
ExecState* exec, Structure* structure, Register* argumentStart, unsigned length,
JSFunction* callee)
{
VM& vm = exec->vm();
ClonedArguments* result = createEmpty(vm, structure, callee);
for (unsigned i = length; i--;)
result->putDirectIndex(exec, i, argumentStart[i].jsValue());
result->putDirect(vm, vm.propertyNames->length, jsNumber(length), DontEnum);
return result;
}
ClonedArguments* ClonedArguments::createWithInlineFrame(ExecState* myFrame, ExecState* targetFrame, InlineCallFrame* inlineCallFrame, ArgumentsMode mode)
{
VM& vm = myFrame->vm();
JSFunction* callee;
if (inlineCallFrame)
callee = jsCast<JSFunction*>(inlineCallFrame->calleeRecovery.recover(targetFrame));
else
callee = jsCast<JSFunction*>(targetFrame->callee());
ClonedArguments* result = createEmpty(myFrame, callee);
unsigned length = 0; // Initialize because VC needs it.
switch (mode) {
case ArgumentsMode::Cloned: {
if (inlineCallFrame) {
if (inlineCallFrame->argumentCountRegister.isValid())
length = targetFrame->r(inlineCallFrame->argumentCountRegister).unboxedInt32();
else
length = inlineCallFrame->arguments.size();
length--;
for (unsigned i = length; i--;)
result->putDirectIndex(myFrame, i, inlineCallFrame->arguments[i + 1].recover(targetFrame));
} else {
length = targetFrame->argumentCount();
for (unsigned i = length; i--;)
result->putDirectIndex(myFrame, i, targetFrame->uncheckedArgument(i));
}
break;
}
case ArgumentsMode::FakeValues: {
length = 0;
break;
} }
result->putDirect(vm, vm.propertyNames->length, jsNumber(length), DontEnum);
return result;
}
