dolphin/Source/Core/VideoCommon/Src/DLCache.cpp

// Copyright (C) 2003-2009 Dolphin Project.

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/

// TODO: Handle cache-is-full condition :p

#include <map>

#include "Common.h"
#include "VideoCommon.h"
#include "Hash.h"
#include "MemoryUtil.h"
#include "DataReader.h"
#include "Statistics.h"
#include "OpcodeDecoding.h"   // For the GX_ constants.

#include "XFMemory.h"
#include "CPMemory.h"
#include "BPMemory.h"

#include "VertexLoaderManager.h"
#include "VertexManagerBase.h"
#include "x64Emitter.h"
#include "ABI.h"

#include "DLCache.h"
#include "VideoConfig.h"

#define DL_CODE_CACHE_SIZE (1024*1024*16)
#define DL_CODE_CLEAR_THRESHOLD (128 * 1024)
extern int frameCount;

using namespace Gen;

namespace DLCache
{

// Currently just recompiles the DLs themselves, doesn't bother with the vertex data.
// The speed boost is pretty small. The real big boost will come when we also store
// vertex arrays in the cached DLs.

enum DisplayListPass {
	DLPASS_ANALYZE,
	DLPASS_COMPILE,
	DLPASS_RUN,
};

#define DL_HASH_STEPS 512

struct ReferencedDataRegion
{
	ReferencedDataRegion()
		:hash(0),
		start_address(NULL),
		size(0),
		MustClean(false),
		NextRegion(NULL)
	{}
	u64 hash;
	u8* start_address;
	u32 size;
	bool MustClean;
	ReferencedDataRegion* NextRegion;

	int IntersectsMemoryRange(u8* range_address, u32 range_size)
	{
		if (start_address + size < range_address)
			return -1;
		if (start_address >= range_address + range_size)
			return 1;
		return 0;
	}
};

struct CachedDisplayList
{
	CachedDisplayList()
			: uncachable(false),
			num_xf_reg(0),
			num_cp_reg(0),
			num_bp_reg(0), 
			num_index_xf(0),
			num_draw_call(0),
			pass(DLPASS_ANALYZE),
			next_check(1),
			BufferCount(0),
			Regions(NULL),
			LastRegion(NULL)
	{
		frame_count = frameCount;
	}
	
	bool uncachable;  // if set, this DL will always be interpreted. This gets set if hash ever changes.
	// Analitic data
	int num_xf_reg;
	int num_cp_reg;
	int num_bp_reg; 
	int num_index_xf;
	int num_draw_call;
	
	int pass;
	u64 dl_hash;

	int check;
	int next_check;

	int frame_count;

	// ... Something containing cached vertex buffers here ...
	int BufferCount;
	ReferencedDataRegion* Regions;
	ReferencedDataRegion* LastRegion;	
	
	// Compile the commands themselves down to native code.
	
	const u8* compiled_code;

	void InsertRegion(ReferencedDataRegion* NewRegion)
	{
		if(LastRegion)
		{
			LastRegion->NextRegion = NewRegion;			
		}
		LastRegion = NewRegion;
		if(!Regions)
		{
			Regions = LastRegion;
		}
		BufferCount++;
	}

	void InsertOverlapingRegion(u8* RegionStartAddress, u32 Size)
	{
		ReferencedDataRegion* NewRegion = FindOverlapingRegion(RegionStartAddress, Size);
		if(NewRegion)
		{
			bool RegionChanged = false;
			if(RegionStartAddress < NewRegion->start_address)
			{
				NewRegion->start_address = RegionStartAddress;
				RegionChanged = true;
			}
			if(RegionStartAddress + Size > NewRegion->start_address + NewRegion->size)
			{
				NewRegion->size += (RegionStartAddress + Size) - (NewRegion->start_address + NewRegion->size);
				RegionChanged = true;
			}
			if(RegionChanged)
				NewRegion->hash = GetHash64(NewRegion->start_address, NewRegion->size, DL_HASH_STEPS);
		}
		else
		{
			NewRegion = new ReferencedDataRegion;
			NewRegion->MustClean = false;
			NewRegion->size = Size;
			NewRegion->start_address = RegionStartAddress; 
			NewRegion->hash = GetHash64(RegionStartAddress, Size, DL_HASH_STEPS);					
			InsertRegion(NewRegion);
		}
	}

	bool CheckRegions()
	{
		ReferencedDataRegion* Current = Regions;
		while(Current)
		{
			if(Current->hash)
			{
				if(Current->hash != GetHash64(Current->start_address,  Current->size, DL_HASH_STEPS))
					return false;
			}
			Current = Current->NextRegion;
		}
		return true;
	}	

	ReferencedDataRegion* FindOverlapingRegion(u8* RegionStart, int Regionsize)
	{
		ReferencedDataRegion* Current = Regions;
		while(Current)
		{
			if(!Current->IntersectsMemoryRange(RegionStart, Regionsize))
					return Current;			
			Current = Current->NextRegion;
		}
		return Current;
	}

	void ClearRegions()
	{
		ReferencedDataRegion* Current = Regions;
		while(Current)
		{
			ReferencedDataRegion* temp = Current;
			Current = Current->NextRegion;
			if(temp->MustClean)
				delete [] temp->start_address;
			delete temp;
		}
		LastRegion = NULL;
		Regions = NULL;
	}
};

// We want to allow caching DLs that start at the same address but have different lengths,
// so the size has to be in the ID.
inline u64 CreateMapId(u32 address, u32 size)
{
	return ((u64)address << 32) | size;
}

inline u64 CreateVMapId(u8 VATUSED)
{
	u64 vmap_id = 0;
	for(int i = 0; i < 8 ; i++)
	{
		if(VATUSED & (1 << i))
		{
			//vmap_id ^= GetHash64((u8*)(&g_VtxAttr[i].g0.),sizeof(VAT),0);
			if(vmap_id != 0)
			{
				vmap_id ^= (((u64)g_VtxAttr[i].g0.Hex) | (((u64)g_VtxAttr[i].g1.Hex) << 32)) ^ (((u64)g_VtxAttr[i].g2.Hex) << 16); 
			}
			else
			{
				vmap_id = (((u64)g_VtxAttr[i].g0.Hex) | (((u64)g_VtxAttr[i].g1.Hex) << 32)) ^ (((u64)g_VtxAttr[i].g2.Hex) << 16);
			}
		}
	}
	return vmap_id;
}

typedef std::map<u64, CachedDisplayList> DLMap;

struct VDlist
{
	DLMap dl_map;
	u8 VATUsed;
	int count;
};

typedef std::map<u64, VDlist> VDLMap;

static VDLMap dl_map;
static u8* dlcode_cache;

static Gen::XEmitter emitter;



// First pass - analyze
u8 AnalyzeAndRunDisplayList(u32 address, int	 size, CachedDisplayList *dl)
{
	int num_xf_reg = 0;
	int num_cp_reg = 0;
	int num_bp_reg = 0; 
	int num_index_xf = 0;
	int num_draw_call = 0;
	u8 result = 0;
	u8* old_pVideoData = g_pVideoData;
	u8* startAddress = Memory_GetPtr(address);

	// Avoid the crash if Memory_GetPtr failed ..
	if (startAddress != 0)
	{
		g_pVideoData = startAddress;

		// temporarily swap dl and non-dl (small "hack" for the stats)
		Statistics::SwapDL();

		u8 *end = g_pVideoData + size;
		while (g_pVideoData < end)
		{
			// Yet another reimplementation of the DL reading...
			int cmd_byte = DataReadU8();
			switch (cmd_byte)
			{
			case GX_NOP:
				break;

			case GX_LOAD_CP_REG: //0x08
				{
					u8 sub_cmd = DataReadU8();
					u32 value = DataReadU32();
					LoadCPReg(sub_cmd, value);
					INCSTAT(stats.thisFrame.numCPLoads);
					num_cp_reg++;
				}
				break;

			case GX_LOAD_XF_REG:
				{
					u32 Cmd2 = DataReadU32();
					int transfer_size = ((Cmd2 >> 16) & 15) + 1;
					u32 xf_address = Cmd2 & 0xFFFF;
					// TODO - speed this up. pshufb?
					u32 data_buffer[16];
					for (int i = 0; i < transfer_size; i++)
						data_buffer[i] = DataReadU32();
					LoadXFReg(transfer_size, xf_address, data_buffer);
					INCSTAT(stats.thisFrame.numXFLoads);
					num_xf_reg++;
				}
				break;

			case GX_LOAD_INDX_A: //used for position matrices
				{
					LoadIndexedXF(DataReadU32(), 0xC);
					num_index_xf++;
				}
				break;
			case GX_LOAD_INDX_B: //used for normal matrices
				{
					LoadIndexedXF(DataReadU32(), 0xD);
					num_index_xf++;
				}
				break;
			case GX_LOAD_INDX_C: //used for postmatrices
				{
					LoadIndexedXF(DataReadU32(), 0xE);
					num_index_xf++;
				}
				break;
			case GX_LOAD_INDX_D: //used for lights
				{
					LoadIndexedXF(DataReadU32(), 0xF);
					num_index_xf++;
				}
				break;
			case GX_CMD_CALL_DL:
				{
					u32 addr = DataReadU32();
					u32 count = DataReadU32();
					ExecuteDisplayList(addr, count);
				}			
				break;
			case GX_CMD_UNKNOWN_METRICS: // zelda 4 swords calls it and checks the metrics registers after that
				DEBUG_LOG(VIDEO, "GX 0x44: %08x", cmd_byte);
				break;
			case GX_CMD_INVL_VC: // Invalidate Vertex Cache	
				DEBUG_LOG(VIDEO, "Invalidate (vertex cache?)");
				break;
			case GX_LOAD_BP_REG: //0x61
				{
					u32 bp_cmd = DataReadU32();
					LoadBPReg(bp_cmd);
					INCSTAT(stats.thisFrame.numBPLoads);
					num_bp_reg++;
				}
				break;

			// draw primitives 
			default:
				if (cmd_byte & 0x80)
				{
					// load vertices (use computed vertex size from FifoCommandRunnable above)
					u16 numVertices = DataReadU16();
					result |= 1 << (cmd_byte & GX_VAT_MASK);
					VertexLoaderManager::RunVertices(
						cmd_byte & GX_VAT_MASK,   // Vertex loader index (0 - 7)
						(cmd_byte & GX_PRIMITIVE_MASK) >> GX_PRIMITIVE_SHIFT,
						numVertices);
					num_draw_call++;
				}
				else
				{
					ERROR_LOG(VIDEO, "OpcodeDecoding::Decode: Illegal command %02x", cmd_byte);
					break;
				}
				break;
			}
		}
		INCSTAT(stats.numDListsCalled);
		INCSTAT(stats.thisFrame.numDListsCalled);
		// un-swap
		Statistics::SwapDL();
	}
	dl->num_bp_reg = num_bp_reg;
	dl->num_cp_reg = num_cp_reg;
	dl->num_draw_call = num_draw_call;
	dl->num_index_xf = num_index_xf;
	dl->num_xf_reg = num_xf_reg;
    // reset to the old pointer
	g_pVideoData = old_pVideoData;	
	return result;
}

// The only sensible way to detect changes to vertex data is to convert several times 
// and hash the output.

// Second pass - compile
// Since some commands can affect the size of other commands, we really have no choice
// but to compile as we go, interpreting the list. We can't compile and then execute, we must
// compile AND execute at the same time. The second time the display list gets called, we already
// have the compiled code so we don't have to interpret anymore, we just run it.
bool CompileAndRunDisplayList(u32 address, int size, CachedDisplayList *dl)
{
	u8* old_pVideoData = g_pVideoData;
	u8* startAddress = Memory_GetPtr(address);

	// Avoid the crash if Memory_GetPtr failed ..
	if (startAddress != 0)
	{
		g_pVideoData = startAddress;

		// temporarily swap dl and non-dl (small "hack" for the stats)
		Statistics::SwapDL();

		u8 *end = g_pVideoData + size;

		emitter.AlignCode4();
		dl->compiled_code = emitter.GetCodePtr();
		emitter.ABI_EmitPrologue(4);

		while (g_pVideoData < end)
		{
			// Yet another reimplementation of the DL reading...
			int cmd_byte = DataReadU8();
			switch (cmd_byte)
			{
			case GX_NOP:
				// Execute
				// Compile
				break;

			case GX_LOAD_CP_REG: //0x08
				{
					// Execute
					u8 sub_cmd = DataReadU8();
					u32 value = DataReadU32();
					LoadCPReg(sub_cmd, value);
					INCSTAT(stats.thisFrame.numCPLoads);

					// Compile
					emitter.ABI_CallFunctionCC((void *)&LoadCPReg, sub_cmd, value);
				}
				break;

			case GX_LOAD_XF_REG:
				{
					// Execute
					u32 Cmd2 = DataReadU32();
					int transfer_size = ((Cmd2 >> 16) & 15) + 1;
					u32 xf_address = Cmd2 & 0xFFFF;
					// TODO - speed this up. pshufb?
					ReferencedDataRegion* NewRegion = new ReferencedDataRegion;
					NewRegion->MustClean = true;
					NewRegion->size = transfer_size * 4;
					NewRegion->start_address = (u8*) new u8[NewRegion->size]; 
					NewRegion->hash = 0;					
					dl->InsertRegion(NewRegion);
					u32 *data_buffer = (u32*)NewRegion->start_address;
					for (int i = 0; i < transfer_size; i++)
						data_buffer[i] = DataReadU32();
					LoadXFReg(transfer_size, xf_address, data_buffer);
					INCSTAT(stats.thisFrame.numXFLoads);
					// Compile
					emitter.ABI_CallFunctionCCP((void *)&LoadXFReg, transfer_size, xf_address, data_buffer);
				}
				break;

			case GX_LOAD_INDX_A: //used for position matrices
				{
					u32 value = DataReadU32();
					// Execute
					LoadIndexedXF(value, 0xC);
					// Compile
					emitter.ABI_CallFunctionCC((void *)&LoadIndexedXF, value, 0xC);
				}
				break;
			case GX_LOAD_INDX_B: //used for normal matrices
				{
					u32 value = DataReadU32();
					// Execute
					LoadIndexedXF(value, 0xD);
					// Compile
					emitter.ABI_CallFunctionCC((void *)&LoadIndexedXF, value, 0xD);
				}
				break;
			case GX_LOAD_INDX_C: //used for postmatrices
				{
					u32 value = DataReadU32();
					// Execute
					LoadIndexedXF(value, 0xE);
					// Compile
					emitter.ABI_CallFunctionCC((void *)&LoadIndexedXF, value, 0xE);
				}
				break;
			case GX_LOAD_INDX_D: //used for lights
				{
					u32 value = DataReadU32();
					// Execute
					LoadIndexedXF(value, 0xF);
					// Compile
					emitter.ABI_CallFunctionCC((void *)&LoadIndexedXF, value, 0xF);
				}
				break;

			case GX_CMD_CALL_DL:
				{
					u32 addr= DataReadU32();
					u32 count = DataReadU32();
					ExecuteDisplayList(addr, count);
					emitter.ABI_CallFunctionCC((void *)&ExecuteDisplayList, addr, count);
				}
				break;

			case GX_CMD_UNKNOWN_METRICS:
				// zelda 4 swords calls it and checks the metrics registers after that
				break;

			case GX_CMD_INVL_VC:// Invalidate	(vertex cache?)	
				DEBUG_LOG(VIDEO, "Invalidate	(vertex cache?)");
				break;

			case GX_LOAD_BP_REG: //0x61
				{
					u32 bp_cmd = DataReadU32();
					// Execute
					LoadBPReg(bp_cmd);
					INCSTAT(stats.thisFrame.numBPLoads);
					// Compile
					emitter.ABI_CallFunctionC((void *)&LoadBPReg, bp_cmd);
				}
				break;

				// draw primitives 
			default:
				if (cmd_byte & 0x80)
				{
					// load vertices (use computed vertex size from FifoCommandRunnable above)

					// Execute
					u16 numVertices = DataReadU16();
					u8* StartAddress = VertexManager::s_pBaseBufferPointer;
					VertexManager::Flush();
					VertexLoaderManager::RunVertices(
						cmd_byte & GX_VAT_MASK,   // Vertex loader index (0 - 7)
						(cmd_byte & GX_PRIMITIVE_MASK) >> GX_PRIMITIVE_SHIFT,
						numVertices);
					u8* EndAddress = VertexManager::s_pCurBufferPointer;
					u32 Vdatasize = (u32)(EndAddress - StartAddress);
					if (size > 0)
					{
					// Compile
						ReferencedDataRegion* NewRegion = new ReferencedDataRegion;
						NewRegion->MustClean = true;
						NewRegion->size = Vdatasize;
						NewRegion->start_address = (u8*)new u8[Vdatasize]; 
						NewRegion->hash = 0;					
						dl->InsertRegion(NewRegion);
						memcpy(NewRegion->start_address, StartAddress, Vdatasize);
						emitter.ABI_CallFunctionCCCP((void *)&VertexLoaderManager::RunCompiledVertices, cmd_byte & GX_VAT_MASK, (cmd_byte & GX_PRIMITIVE_MASK) >> GX_PRIMITIVE_SHIFT, numVertices, NewRegion->start_address);	
						/*ReferencedDataRegion* VatRegion = new ReferencedDataRegion;
						VatRegion->MustClean = false;
						VatRegion->size = sizeof(VAT);
						VatRegion->start_address = (u8*)(&g_VtxAttr[cmd_byte & GX_VAT_MASK]); 
						VatRegion->hash = GetHash64(NewRegion->start_address, VatRegion->size, 0);
						dl->InsertRegion(VatRegion);*/
					}					
					const int tc[12] = {
						g_VtxDesc.Position, g_VtxDesc.Normal, g_VtxDesc.Color0, g_VtxDesc.Color1, g_VtxDesc.Tex0Coord, g_VtxDesc.Tex1Coord, 
						g_VtxDesc.Tex2Coord, g_VtxDesc.Tex3Coord, g_VtxDesc.Tex4Coord, g_VtxDesc.Tex5Coord, g_VtxDesc.Tex6Coord, (g_VtxDesc.Hex >> 31) & 3
					};
					for(int i = 0; i < 12; i++)
					{
						if(tc[i] > 1)
						{
							u8* saddr = cached_arraybases[i];
							int arraySize = arraystrides[i] * ((tc[i] == 2)? numVertices : ((numVertices < 1024)? 2 * numVertices : numVertices));
							dl->InsertOverlapingRegion(saddr, arraySize);
						}
					}
				}
				else
				{
					ERROR_LOG(VIDEO, "DLCache::CompileAndRun: Illegal command %02x", cmd_byte);
					break;
				}
				break;
			}
		}
		emitter.ABI_EmitEpilogue(4);
		INCSTAT(stats.numDListsCalled);
		INCSTAT(stats.thisFrame.numDListsCalled);
		Statistics::SwapDL();
	}
	g_pVideoData = old_pVideoData;
	return true;
}

void Init()
{
	dlcode_cache = (u8*)AllocateExecutableMemory(DL_CODE_CACHE_SIZE, false);  // Don't need low memory.
	emitter.SetCodePtr(dlcode_cache);
}

void Shutdown()
{
	Clear();
	FreeMemoryPages(dlcode_cache, DL_CODE_CACHE_SIZE);	
	dlcode_cache = NULL;
}

void Clear() 
{
	VDLMap::iterator iter = dl_map.begin();
	while (iter != dl_map.end()) {
		VDlist &ParentEntry = iter->second;
		DLMap::iterator childiter = ParentEntry.dl_map.begin();
		while (childiter != ParentEntry.dl_map.end()) {
			CachedDisplayList &entry = childiter->second;
			entry.ClearRegions();
			childiter++;
		}
		ParentEntry.dl_map.clear();
		iter++;
	}
	dl_map.clear();
	// Reset the cache pointers.
	emitter.SetCodePtr(dlcode_cache);	
}

void ProgressiveCleanup()
{
	VDLMap::iterator iter = dl_map.begin();
	while (iter != dl_map.end()) {
		VDlist &ParentEntry = iter->second;
		DLMap::iterator childiter = ParentEntry.dl_map.begin();
		while (childiter != ParentEntry.dl_map.end()) 
		{
			CachedDisplayList &entry = childiter->second;
			int limit = 3600;
			if (entry.frame_count < frameCount - limit) {
				// entry.Destroy();
				entry.ClearRegions();
				ParentEntry.dl_map.erase(childiter++);  // (this is gcc standard!)
			}
			else
				++childiter;
		}
		if(ParentEntry.dl_map.empty())
		{
			dl_map.erase(iter++);
		}
		else
			iter++;
	}
}

static size_t GetSpaceLeft()
{
	return DL_CODE_CACHE_SIZE - (emitter.GetCodePtr() - dlcode_cache);
}

}  // namespace

// NOTE - outside the namespace on purpose.
bool HandleDisplayList(u32 address, u32 size)
{
	//Fixed DlistCaching now is fully functional still some things to workout
	if(!g_ActiveConfig.bDlistCachingEnable)
		return false;
	if(size == 0) return false;

	// Is this thread safe?
	if (DLCache::GetSpaceLeft() < DL_CODE_CLEAR_THRESHOLD) {
		DLCache::Clear();
	}

	u64 dl_id = DLCache::CreateMapId(address, size);
	u64 vhash = 0;
	DLCache::VDLMap::iterator Parentiter = DLCache::dl_map.find(dl_id);
	DLCache::DLMap::iterator iter;
	bool childexist = false;
	if (Parentiter != DLCache::dl_map.end())
	{
		vhash = DLCache::CreateVMapId(Parentiter->second.VATUsed);
		iter = 	Parentiter->second.dl_map.find(vhash);
		childexist = iter != Parentiter->second.dl_map.end();		
	}
	//INCSTAT(stats.numDListsAlive);
	if (Parentiter != DLCache::dl_map.end() && childexist)
	{
		DLCache::CachedDisplayList &dl = iter->second;
		if (dl.uncachable)
		{
			return false;			
		}

		// Got one! And it's been compiled too, so let's run the compiled code!
		switch (dl.pass)
		{
		case DLCache::DLPASS_COMPILE:
			// First, check that the hash is the same as the last time.
			if (dl.dl_hash != GetHash64(Memory_GetPtr(address), size, 0))
			{
				// PanicAlert("uncachable %08x", address);
				dl.uncachable = true;				
				return false;
			}
			DLCache::CompileAndRunDisplayList(address, size, &dl);
			dl.pass = DLCache::DLPASS_RUN;
			break;
		case DLCache::DLPASS_RUN:
			{
				// Every N draws, check hash
				dl.check--;
				if (dl.check <= 0)
				{
					if (dl.dl_hash != GetHash64(Memory_GetPtr(address), size, 0) || !dl.CheckRegions()) 
					{
						dl.uncachable = true;
						dl.check = 60;
						dl.ClearRegions();						
						return false;
					}
					dl.check = dl.next_check;
					/*dl.next_check ++;
					if (dl.next_check > 60)
						dl.next_check = 60;*/
				}
				dl.frame_count= frameCount;
				u8 *old_datareader = g_pVideoData;
				((void (*)())(void*)(dl.compiled_code))();
				Statistics::SwapDL();
				ADDSTAT(stats.thisFrame.numCPLoadsInDL, dl.num_cp_reg);
				ADDSTAT(stats.thisFrame.numXFLoadsInDL, dl.num_xf_reg);
				ADDSTAT(stats.thisFrame.numBPLoadsInDL, dl.num_bp_reg);

				ADDSTAT(stats.thisFrame.numCPLoads, dl.num_cp_reg);
				ADDSTAT(stats.thisFrame.numXFLoads, dl.num_xf_reg);
				ADDSTAT(stats.thisFrame.numBPLoads, dl.num_bp_reg);

				INCSTAT(stats.numDListsCalled);
				INCSTAT(stats.thisFrame.numDListsCalled);
				
				Statistics::SwapDL();
				g_pVideoData = old_datareader;
				break;
			}
		}
		return true;
	}

	DLCache::CachedDisplayList dl;
	
	u8 dlvatused = DLCache::AnalyzeAndRunDisplayList(address, size, &dl);
	dl.dl_hash = GetHash64(Memory_GetPtr(address), size,0);
	dl.pass = DLCache::DLPASS_COMPILE;
	dl.check = 1;
	dl.next_check = 1;
	
	if(Parentiter != DLCache::dl_map.end())
	{
		DLCache::VDlist &vdl = Parentiter->second;
		vdl.dl_map[vhash] = dl;
		vdl.VATUsed = dlvatused; 
		vdl.count++;
	}
	else
	{
		DLCache::VDlist vdl;
		vdl.dl_map[vhash] = dl;
		vdl.VATUsed = dlvatused; 
		vdl.count = 1;
		DLCache::dl_map[dl_id] = vdl;

	}
	return true;
	
}