/// <summary>
///
/// </summary>
/// <param name="vmClass"></param>
/// <returns>绝对地址</returns>
public uint MallocClassStaticArea(VMClass vmClass)
{
HeapData ret = Malloc(vmClass.StaticFieldSize);
// TODO 头部信息暂时不知道填什么
return(MemoryMap.MapToAbsolute(ret.Offset, MemoryTag.STATIC));
}
/// <summary>
///
/// </summary>
/// <param name="objectClass"></param>
/// <returns>绝对地址</returns>
public uint New(VMClass objectClass)
{
HeapData data = Malloc(objectClass.FieldSize);
// 类型信息
data.TypeInfo = objectClass.StaticFieldAddress;
return(MemoryMap.MapToAbsolute(data.Offset, MemoryTag.HEAP));
}
/// <summary>
/// 数组
/// </summary>
/// <param name="typeTag"></param>
/// <param name="len"></param>
/// <returns></returns>
public uint MallocArray(VariableTypeTag typeTag, int len)
{
int size = len * VariableType.GetSize(typeTag) + HeapData.MiscDataSize + HeapData.ArrayLengthSize;
HeapData ret = Malloc(size);
// 数组长度
BitConverter.TryWriteBytes(new Span <byte>(ret.Data, HeapData.MiscDataSize, HeapData.ArrayLengthSize), len);
// GC的数组tag
BitConverter.TryWriteBytes(new Span <byte>(ret.Data, sizeof(uint), sizeof(uint)), (uint)GCTag.ArrayMark);
// 数组的Type是基本类型
ret.TypeInfo = (uint)typeTag;
return(MemoryMap.MapToAbsolute(ret.Offset, MemoryTag.HEAP));
}
/// <summary>
/// 注意要和SystemLib中的String的对象格式相同
/// </summary>
/// <param name="value"></param>
/// <returns>绝对地址</returns>
public uint AddConstantString(string value)
{
if (!StringPool.TryGetValue(value, out HeapData data))
{
// 分配byte数组
HeapData stringData = MallocCharArray(Encoding.UTF8.GetByteCount(value));
Encoding.UTF8.GetBytes(value, new Span <byte>(stringData.Data, HeapData.ArrayLengthSize + HeapData.MiscDataSize,
stringData.Data.Length - HeapData.ArrayLengthSize - HeapData.MiscDataSize));
// String对象
byte[] vs = new byte[HeapData.MiscDataSize + HeapData.StringLengthSize + HeapData.StringDataSize];
// 头部信息可以不填，因为MethodArea是内存的边界，GC不会继续walk
// 长度信息
BitConverter.TryWriteBytes(new Span <byte>(vs, HeapData.MiscDataSize, HeapData.StringLengthSize), value.Length);
// Data信息
BitConverter.TryWriteBytes(new Span <byte>(vs, HeapData.MiscDataSize + HeapData.StringLengthSize, HeapData.StringDataSize),
MemoryMap.MapToAbsolute(stringData.Offset, MemoryTag.METHOD));
// 字符串
data = Malloc(vs);
StringPool.Add(value, data);
}
return(MemoryMap.MapToAbsolute(data.Offset, MemoryTag.METHOD));
}
public static void CollectGarbage()
{
GCWatch.Start();
// 从stack出发
foreach (var thread in ThreadManager.Threads)
{
// 要保证GC执行期间线程全部停止
for (uint i = 0; i < thread.Stack.SP; ++i)
{
if (thread.Stack.Slots[i].DataTag == SlotDataTag.ADDRESS)
{
MarkObject(thread.Stack.GetAddress(i));
}
}
}
// 从类的静态区出发
foreach (var staticClassData in StaticArea.Singleton.DataMap.Values)
{
uint addr = MemoryMap.MapToAbsolute(staticClassData.Offset, MemoryTag.STATIC);
ModuleLoader.Classes.TryGetValue(addr, out VMClass vmClass);
foreach (var staticField in vmClass.StaticFields)
{
if (staticField.Type.Tag == VariableTypeTag.ADDRESS)
{
// 是地址
MarkObject(BitConverter.ToUInt32(staticClassData.Data, staticField.Offset));
}
}
}
// 回收
LinkedListNode <HeapData> cur = Heap.Singleton.Data.First;
while (cur != null)
{
if ((cur.Value.GCInfo & (uint)GCTag.GCMark) == 0)
{
// 不可达对象，删除
LinkedListNode <HeapData> tmp = cur;
cur = cur.Next;
Heap.Singleton.DataMap.Remove(tmp.Value.Offset);
Heap.Singleton.Data.Remove(tmp);
Heap.Singleton.Size -= tmp.Value.Data.Length;
FreedSize += tmp.Value.Data.Length / 1024;
}
else
{
// 清除GCMark
cur.Value.GCInfo = cur.Value.GCInfo & (~(uint)GCTag.GCMark);
cur = cur.Next;
}
}
GCWatch.Stop();
GCTotalTime += GCWatch.ElapsedMilliseconds;
if (GCWatch.ElapsedMilliseconds > GCMaxTime)
{
GCMaxTime = GCWatch.ElapsedMilliseconds;
}
GCCount++;
}
public static uint GetAbsoluteAddress(PreservedAddressTag tag)
{
return(MemoryMap.MapToAbsolute((uint)tag, MemoryTag.PRESERVED));
}
