/// <summary>
/// Allocates a new class of the given type
/// </summary>
/// <param name="classType">The type of the class</param>
public IntPtr NewClass(ClassType classType)
{
var classPointer = this.AllocateObject(this.youngGeneration, classType, classType.Metadata.Size);
if (this.virtualMachine.Config.EnableDebug && this.virtualMachine.Config.PrintAllocation)
{
RuntimeInterface.DebugLog($"Allocated class of type '{classType}' at 0x{classPointer.ToString("x8")}.");
}
return(classPointer);
}
/// <summary>
/// Allocates a new array of the given type and length
/// </summary>
/// <param name="arrayType">The type of the array</param>
/// <param name="length">The length</param>
public IntPtr NewArray(ArrayType arrayType, int length)
{
var elementType = arrayType.ElementType;
var elementSize = TypeSystem.SizeOf(elementType);
var objectSize = Constants.ArrayLengthSize + (length * elementSize);
var arrayPointer = this.AllocateObject(this.youngGeneration, arrayType, objectSize);
//Set the length of the array
NativeHelpers.SetInt(arrayPointer, 0, length);
if (this.virtualMachine.Config.EnableDebug && this.virtualMachine.Config.PrintAllocation)
{
RuntimeInterface.DebugLog($"Allocated array (length: {length}) with element type '{elementType}' at 0x{arrayPointer.ToString("x8")}.");
}
return(arrayPointer);
}
/// <summary>
/// Starts a garbage collection at the given stack frame
/// </summary>
/// <param name="stackFrame">The current stack frame</param>
public void Collect(StackFrame stackFrame)
{
if (this.virtualMachine.Config.EnableDebug && this.virtualMachine.Config.PrintAliveObjectsWhenGC)
{
RuntimeInterface.DebugLog("Alive objects:");
youngGeneration.Heap.VisitObjects(objectReference =>
{
RuntimeInterface.DebugLog(objectReference.ToString());
});
RuntimeInterface.DebugLog("");
}
if (this.virtualMachine.Config.LogDeallocation)
{
this.Deallocations.Add(new List <IntPtr>());
}
this.MarkAllObjects(this.youngGeneration, stackFrame);
this.SweepObjects(this.youngGeneration);
}
/// <summary>
/// Sweeps the objects in the given generation
/// </summary>
/// <param name="generation">The generation</param>
private void SweepObjects(CollectorGeneration generation)
{
generation.Heap.VisitObjects(objectReference =>
{
if (objectReference.IsMarked)
{
objectReference.Unmark();
objectReference.IncreaseSurvivalCount();
}
else
{
if (this.virtualMachine.Config.EnableDebug && this.virtualMachine.Config.PrintDeallocation)
{
RuntimeInterface.DebugLog($"Deleted object {objectReference}");
}
this.DeleteObject(objectReference);
}
});
}
/// <summary>
/// Marks all the objects starting at the given frame
/// </summary>
/// <param name="generation">The generation</param>
/// <param name="stackFrame">The stack frame</param>
private void MarkAllObjects(CollectorGeneration generation, StackFrame stackFrame)
{
var stalkWalker = new StackWalker(this.virtualMachine.CallStack);
stalkWalker.VisitObjectReferences(
stackFrame,
frameEntry =>
{
var objectPointer = new IntPtr(frameEntry.Value);
this.MarkObject(generation, this.GetObjectReference(objectPointer));
},
frame =>
{
if (this.virtualMachine.Config.EnableDebug && this.virtualMachine.Config.PrintStackFrameWhenGC)
{
RuntimeInterface.DebugLog($"{frame.Function.Definition.Name} ({frame.InstructionIndex})");
RuntimeInterface.PrintStackFrame(frame, false);
}
});
}