public void AllocateReplacesVariables()
{
var executor = new ByteCodeExecutor(new ByteCodePoint[0], new ILiteral[0], 2);
var someValue = Literal.NewAtom();
executor.Register(0).SetTo(new SimpleReference(someValue, new SimpleReference()));
Assert.AreEqual(someValue, executor.Register(0).Term, "Term is initially set");
executor.Dispatch(new ByteCodePoint(Operation.Allocate, 1, 0));
Assert.AreNotEqual(someValue, executor.Register(0).Term, "Term is replaced by allocate");
}
public void AllocatePreservesArgumentsByMovingUp()
{
var executor = new ByteCodeExecutor(new ByteCodePoint[0], new ILiteral[0], 2);
var someValue = Literal.NewAtom();
executor.Register(0).SetTo(new SimpleReference(someValue, new SimpleReference()));
Assert.AreEqual(someValue, executor.Register(0).Term, "Term is initially set");
executor.Dispatch(new ByteCodePoint(Operation.Allocate, 1, 1));
Assert.AreEqual(someValue, executor.Register(1).Term, "Argument is preserved by allocate");
}
public void PermanentVariablesAreRestored()
{
var executor = new ByteCodeExecutor(new ByteCodePoint[0], new ILiteral[0], 2);
// Allocate a permanent variable
executor.Dispatch(new ByteCodePoint(Operation.Allocate, 1, 0));
// Set it to something
var someValue = Literal.NewAtom();
executor.Register(0).SetTo(new SimpleReference(someValue, new SimpleReference()));
Assert.AreEqual(someValue, executor.Register(0).Term, "Term is initially set");
// Allocate another frame
executor.Dispatch(new ByteCodePoint(Operation.Allocate, 1, 0));
Assert.AreNotEqual(someValue, executor.Register(0).Term, "Term is replaced by allocate");
// Restore the original value using deallocate
executor.Dispatch(new ByteCodePoint(Operation.Deallocate));
Assert.AreEqual(someValue, executor.Register(0).Term);
}
