public void TestGCStringCleanup()
{
// Simulating the following graph
/*
* def generateString() {
* return 1+"@" +2;
* };
*
* vv = [Imperative]{
* generateString();
* // "1@2" will be on the heap
* // current stack has no reference type elements
* // --------------------------------GC kicks in due to mem threshold----------------------------
* // "1@2" on the heap will be marked as white - since no stack elements have a reference to it
* //
* // Async VM execution computes a new generateString() fn Call
* cc = generateString();
* //
* // cc is pushed on the stack and holds a reference to the "1@2" heap element
* //
* // GC starts the sweep process in which it deletes "1@2" heap element
* // ----------------------------------GC is finished---------------------------------------------
* return cc;
* };
* //
* // vv is still on the stack with a reference to a now null heap element
*/
var heap = new Heap();
string sseValue = "hello world";
// Allocate a string on the heap.
// Similar to what would happen if a string stack element was pushed on the stack and then popped (due to out of scope).
heap.AllocateString(sseValue);
StackValue someStackValue = StackValue.BuildNull();
var notifications = new Dictionary <Heap.GCState, (Action, Action)>()
{
{
Heap.GCState.Sweep,
(() => {
// Simulate a new string (with the same value as existing one on heap) stack element being created while GC is propagating or sweeping
someStackValue = heap.AllocateString(sseValue);
},
() => { })
}
};
// Start GC with a random stack value as gcRoot (not the string stack element, because it was pushed out of the stack)
heap.FullGCTest(new List <StackValue>()
{
StackValue.BuildInt(1)
}, testExecutive, notifications);
// The stack element that was pushed after GC start should be valid.
Assert.IsNotNull(heap.ToHeapObject <DSString>(someStackValue));
}
public void TestBasic()
{
var heap = new Heap();
var values = new StackValue[]
{
StackValue.BuildInt(0),
StackValue.BuildInt(1),
StackValue.BuildInt(2)
};
var array = heap.AllocateArray(values);
var str = heap.AllocateString("hello world");
heap.GCMarkAndSweep(new List <StackValue>(), testExecutive);
Assert.IsNull(heap.ToHeapObject <DSArray>(array));
Assert.IsNull(heap.ToHeapObject <DSArray>(str));
}
public void TestDictionary()
{
var heap = new Heap();
var key = heap.AllocateArray(new StackValue[] { StackValue.BuildInt(42) });
var val = heap.AllocateString("Hello world");
var dict = new Dictionary <StackValue, StackValue>();
dict[key] = val;
var array = heap.AllocateArray(new StackValue[] { });
heap.GCMarkAndSweep(new List <StackValue>()
{
}, testExecutive);
Assert.IsNull(heap.ToHeapObject <DSArray>(val));
Assert.IsNull(heap.ToHeapObject <DSArray>(array));
}
public void TestBasic()
{
var heap = new Heap();
var values = new StackValue[]
{
StackValue.BuildInt(0),
StackValue.BuildInt(1),
StackValue.BuildInt(2)
};
var array = heap.AllocateArray(values);
var str = heap.AllocateString("hello world");
heap.GCMarkAndSweep(new List <StackValue>(), testExecutive);
HeapElement arrayHeapElement;
Assert.IsFalse(heap.TryGetHeapElement(array, out arrayHeapElement));
HeapElement strHeapElement;
Assert.IsFalse(heap.TryGetHeapElement(str, out strHeapElement));
}
public void TestDictionary()
{
var heap = new Heap();
var key = heap.AllocateArray(new StackValue[] { StackValue.BuildInt(42) });
var val = heap.AllocateString("Hello world");
var dict = new Dictionary <StackValue, StackValue>();
dict[key] = val;
var array = heap.AllocateArray(new StackValue[] { }, dict);
heap.GCMarkAndSweep(new List <StackValue>()
{
}, testExecutive);
HeapElement valHeapElement;
Assert.IsFalse(heap.TryGetHeapElement(val, out valHeapElement));
HeapElement arrayHeapElement;
Assert.IsFalse(heap.TryGetHeapElement(array, out arrayHeapElement));
}
