Function MarkPointer

NULLC/translation/runtime.cpp:829–862

Function that marks memory blocks belonging to GC

	// Function that marks memory blocks belonging to GC
	void MarkPointer(char* ptr, const NULLCTypeInfo& type, bool takeSubtype)
	{
		// We have pointer to stack that has a pointer inside, so 'ptr' is really a pointer to pointer
		char **rPtr = (char**)ptr;
		// Check for unmanageable ranges. Range of 0x00000000-0x00010000 is unmanageable by default due to upvalues with offsets inside closures.
		if(*rPtr > (char*)0x00010000 && (*rPtr < unmanageableBase || *rPtr > unmanageableTop))
		{
			// Get type that pointer points to
			GC_DEBUG_PRINT("\tGlobal pointer %s %p (at %p)\r\n", type.name, *rPtr, ptr);

			// Get pointer to the start of memory block. Some pointers may point to the middle of memory blocks
			unsigned int *basePtr = (unsigned int*)NULLC::GetBasePointer(*rPtr);
			// If there is no base, this pointer points to memory that is not GCs memory
			if(!basePtr)
				return;
			GC_DEBUG_PRINT("\tPointer base is %p\r\n", basePtr);
			// Marker is 4 bytes before the block
			unsigned int *marker = (unsigned int*)(basePtr)-1;
			GC_DEBUG_PRINT("\tMarker is %d\r\n", *marker & 0xff);

			// If block is unmarked
			if((*marker & 0xff) == 0)
			{
				// Mark block as used
				*marker |= 1;
				GC_DEBUG_PRINT("Type near memory %d, type %d (%d)\n", *marker >> 8, type.subTypeID, takeSubtype);
				// And if type is not simple, check memory to which pointer points to
				if(type.category != NULLC_NONE)
					CheckVariable(*rPtr, takeSubtype ? __nullcTypeList[/*type.subTypeID*/*marker >> 8] : type);
			}else if(takeSubtype && __nullcTypeList[type.subTypeID].category == NULLC_POINTER){
				MarkPointer(*rPtr, __nullcTypeList[type.subTypeID], true); 
			}
		}
	}

	// Function that checks arrays for pointers
	void CheckArray(char* ptr, const NULLCTypeInfo& type)