public static void GarbageCollect() { #if NO tHeapRoots heapRoots; tHeapEntry * pNode; tHeapEntry **pUp = stackalloc tHeapEntry *[MAX_TREE_DEPTH * 2]; int top; tHeapEntry * pToDelete = null; SIZE_T orgHeapSize = trackHeapSize; uint orgNumNodes = numNodes; #if DIAG_GC ulong startTime; #endif Mem.heapcheck(); numCollections++; #if DIAG_GC startTime = microTime(); #endif heapRoots.capacity = 64; heapRoots.num = 0; heapRoots.pHeapEntries = (tHeapRootEntry *)Mem.malloc(heapRoots.capacity * (SIZE_T)sizeof(tHeapRootEntry)); Thread.GetHeapRoots(&heapRoots); CLIFile.GetHeapRoots(&heapRoots); // Mark phase while (heapRoots.num > 0) { tHeapRootEntry *pRootsEntry; uint i; uint moreRootsAdded = 0; uint rootsEntryNumPointers; void ** pRootsEntryMem; // Get a piece of memory off the list of heap memory roots. pRootsEntry = &heapRoots.pHeapEntries[heapRoots.num - 1]; rootsEntryNumPointers = pRootsEntry->numPointers; pRootsEntryMem = pRootsEntry->pMem; // Mark this entry as done pRootsEntry->numPointers = 0; pRootsEntry->pMem = null; // Iterate through all pointers in it for (i = 0; i < rootsEntryNumPointers; i++) { void *pMemRef = pRootsEntryMem[i]; // Quick escape for known non-memory if (pMemRef == null) { continue; } // Find this piece of heap memory in the tracking tree. // Note that the 2nd memory address comparison MUST be >, not >= as might be expected, // to allow for a zero-sized memory to be detected (and not garbage collected) properly. // E.g. The object class has zero memory. pNode = pHeapTreeRoot; while (pNode != nil) { if (pMemRef < (void *)pNode) { pNode = (tHeapEntry *)pNode->pLink[0]; } else if ((byte *)pMemRef > ((byte *)pNode) + GetSize(pNode) + sizeof(tHeapEntry)) { pNode = (tHeapEntry *)pNode->pLink[1]; } else { // Found memory. See if it's already been marked. // If it's already marked, then don't do anything. // It it's not marked, then add all of its memory to the roots, and mark it. if (pNode->marked == 0) { tMD_TypeDef *pType = pNode->pTypeDef; // Not yet marked, so mark it, and add it to heap roots. pNode->marked = 1; // Don't look at the contents of strings, arrays of primitive Type.types, or WeakReferences if (pType->stackType == EvalStack.EVALSTACK_O || pType->stackType == EvalStack.EVALSTACK_VALUETYPE || pType->stackType == EvalStack.EVALSTACK_PTR) { if (pType != Type.types[Type.TYPE_SYSTEM_STRING] && (!MetaData.TYPE_ISARRAY(pType) || pType->pArrayElementType->stackType == EvalStack.EVALSTACK_O || pType->pArrayElementType->stackType == EvalStack.EVALSTACK_VALUETYPE || pType->pArrayElementType->stackType == EvalStack.EVALSTACK_PTR)) { if (pType != Type.types[Type.TYPE_SYSTEM_WEAKREFERENCE]) { Heap.SetRoots(&heapRoots, ((byte *)&pNode->pSync + sizeof(PTR)), GetSize(pNode)); moreRootsAdded = 1; } } } } break; } } } if (moreRootsAdded == 0) { heapRoots.num--; } } Mem.free(heapRoots.pHeapEntries); // Sweep phase // Traverse nodes pUp[0] = pHeapTreeRoot; top = 1; while (top != 0) { // Get this node pNode = pUp[--top]; // Act on this node if (pNode->marked != 0) { if (pNode->marked != 0xff) { // Still in use (but not marked undeletable), so unmark pNode->marked = 0; } } else { // Not in use any more, so put in deletion queue if it does not need Finalizing // If it does need Finalizing, then don't garbage collect, and put in Finalization queue. if (pNode->needToFinalize != 0) { if (pNode->needToFinalize == 1) { Finalizer.AddFinalizer((/*HEAP_PTR*/ byte *)pNode + sizeof(tHeapEntry)); // Mark it has having been placed in the finalization queue. // When it has been finalized, then this will be set to 0 pNode->needToFinalize = 2; // If this object is being targetted by weak-ref(s), handle it if (pNode->pSync != null) { RemoveWeakRefTarget(pNode, 0); Mem.free(pNode->pSync); } } } else { // If this object is being targetted by weak-ref(s), handle it if (pNode->pSync != null) { RemoveWeakRefTarget(pNode, 1); Mem.free(pNode->pSync); } // Use pSync to point to next entry in this linked-list. pNode->pSync = (tSync *)pToDelete; pToDelete = pNode; } } // Get next node(s) if (pNode->pLink[1] != (PTR)nil) { pUp[top++] = (tHeapEntry *)pNode->pLink[1]; } if (pNode->pLink[0] != (PTR)nil) { pUp[top++] = (tHeapEntry *)pNode->pLink[0]; } } // Delete all unused memory nodes. while (pToDelete != null) { tHeapEntry *pThis = pToDelete; pToDelete = (tHeapEntry *)(pToDelete->pSync); pHeapTreeRoot = TreeRemove(pHeapTreeRoot, pThis); if (pThis->monoHandle == 1) { void *hptr = *(void **)((byte *)pThis + sizeof(tHeapEntry)); if (hptr != null) { H.Free(hptr); } } numNodes--; trackHeapSize -= GetSize(pThis) + (uint)sizeof(tHeapEntry); Mem.free(pThis); } Mem.heapcheck(); #if DIAG_GC gcTotalTime += microTime() - startTime; #endif Sys.log_f(1, "--- GARBAGE --- [Size: %d -> %d] [Nodes: %d -> %d]\n", orgHeapSize, trackHeapSize, orgNumNodes, numNodes); #if DIAG_GC Sys.log_f(1, "GC time = %d ms\n", gcTotalTime / 1000); #endif #endif }