_Must_inspect_result_ bool WebAssemblySharedArrayBuffer::GrowMemory(uint32 newBufferLength)
{
uint32 bufferLength = sharedContents->bufferLength;
BYTE* buffer = sharedContents->buffer;
if (newBufferLength < bufferLength || newBufferLength > sharedContents->maxBufferLength)
{
AssertMsg(newBufferLength <= sharedContents->maxBufferLength, "This shouldn't happen");
Assert(UNREACHED);
JavascriptError::ThrowTypeError(GetScriptContext(), WASMERR_BufferGrowOnly);
}
uint32 growSize = newBufferLength - bufferLength;
// We're not growing the buffer, do nothing
if (growSize == 0)
{
return true;
}
AssertOrFailFast(buffer);
if (IsValidVirtualBufferLength(newBufferLength))
{
auto virtualAllocFunc = [=]
{
return !!VirtualAlloc(buffer + bufferLength, growSize, MEM_COMMIT, PAGE_READWRITE);
};
if (!this->GetRecycler()->DoExternalAllocation(growSize, virtualAllocFunc))
{
return false;
}
this->GetRecycler()->AddExternalMemoryUsage(growSize);
}
else
{
// We have already allocated maxLength in the heap if we're not using virtual alloc
}
ZeroMemory(buffer + bufferLength, growSize);
sharedContents->bufferLength = newBufferLength;
ValidateBuffer();
return true;
}
void WebAssemblySharedArrayBuffer::FreeBuffer(BYTE* buffer, uint32 length, uint32 maxLength)
{
if (IsValidVirtualBufferLength(length))
{
FreeMemAlloc(buffer);
}
else
{
HeapDeleteArray(maxLength, buffer);
AssertOrFailFast(maxLength >= length);
// JavascriptSharedArrayBuffer::Finalize will only report freeing `length`, we have to take care of the balance
uint32 additionalSize = maxLength - length;
if (additionalSize > 0)
{
Recycler* recycler = GetType()->GetLibrary()->GetRecycler();
recycler->ReportExternalMemoryFree(additionalSize);
}
}
}
void JavascriptSharedArrayBuffer::Finalize(bool isShutdown)
{
if (sharedContents == nullptr)
{
return;
}
uint ref = InterlockedDecrement(&sharedContents->refCount);
if (ref == 0)
{
#if _WIN64
//AsmJS Virtual Free
//TOD - see if isBufferCleared need to be added for free too
if (IsValidVirtualBufferLength(sharedContents->bufferLength) && !sharedContents->isBufferCleared)
{
LPVOID startBuffer = (LPVOID)((uint64)sharedContents->buffer);
BOOL fSuccess = VirtualFree((LPVOID)startBuffer, 0, MEM_RELEASE);
Assert(fSuccess);
sharedContents->isBufferCleared = true;
}
else
{
free(sharedContents->buffer);
}
#else
free(sharedContents->buffer);
#endif
Recycler* recycler = GetType()->GetLibrary()->GetRecycler();
recycler->ReportExternalMemoryFree(sharedContents->bufferLength);
sharedContents->Cleanup();
HeapDelete(sharedContents);
}
sharedContents = nullptr;
}
JavascriptSharedArrayBuffer::JavascriptSharedArrayBuffer(uint32 length, DynamicType * type) :
SharedArrayBuffer(length, type, (IsValidVirtualBufferLength(length)) ? AllocWrapper : malloc)
{
}
