/// <summary>
/// Subtask constructor </summary>
internal DoubleCumulateTask(DoubleCumulateTask parent, DoubleBinaryOperator function, double[] array, int origin, int fence, int threshold, int lo, int hi) : base(parent)
{
this.Function = function;
this.Array = array;
this.Origin = origin;
this.Fence = fence;
this.Threshold = threshold;
this.Lo = lo;
this.Hi = hi;
}
/// <summary>
/// Root task constructor </summary>
public DoubleCumulateTask(DoubleCumulateTask parent, DoubleBinaryOperator function, double[] array, int lo, int hi) : base(parent)
{
this.Function = function;
this.Array = array;
this.Lo = this.Origin = lo;
this.Hi = this.Fence = hi;
int p;
this.Threshold = (p = (hi - lo) / (ForkJoinPool.CommonPoolParallelism << 3)) <= MIN_PARTITION ? MIN_PARTITION : p;
}
public void Compute()
{
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final java.util.function.DoubleBinaryOperator fn;
DoubleBinaryOperator fn;
//JAVA TO C# CONVERTER WARNING: The original Java variable was marked 'final':
//ORIGINAL LINE: final double[] a;
double[] a;
if ((fn = this.Function) == null || (a = this.Array) == null)
{
throw new NullPointerException(); // hoist checks
}
int th = Threshold, org = Origin, fnc = Fence, l, h;
DoubleCumulateTask t = this;
while ((l = t.Lo) >= 0 && (h = t.Hi) <= a.Length)
{
if (h - l > th)
{
DoubleCumulateTask lt = t.Left, rt = t.Right, f;
if (lt == null) // first pass
{
int mid = (int)((uint)(l + h) >> 1);
f = rt = t.Right = new DoubleCumulateTask(t, fn, a, org, fnc, th, mid, h);
t = lt = t.Left = new DoubleCumulateTask(t, fn, a, org, fnc, th, l, mid);
}
else // possibly refork
{
double pin = t.@in;
lt.@in = pin;
f = t = null;
if (rt != null)
{
double lout = lt.@out;
rt.@in = (l == org ? lout : fn.ApplyAsDouble(pin, lout));
for (int c;;)
{
if (((c = rt.PendingCount) & CUMULATE) != 0)
{
break;
}
if (rt.CompareAndSetPendingCount(c, c | CUMULATE))
{
t = rt;
break;
}
}
}
for (int c;;)
{
if (((c = lt.PendingCount) & CUMULATE) != 0)
{
break;
}
if (lt.CompareAndSetPendingCount(c, c | CUMULATE))
{
if (t != null)
{
f = t;
}
t = lt;
break;
}
}
if (t == null)
{
break;
}
}
if (f != null)
{
f.Fork();
}
}
else
{
int state; // Transition to sum, cumulate, or both
for (int b;;)
{
if (((b = t.PendingCount) & FINISHED) != 0)
{
goto outerBreak; // already done
}
state = ((b & CUMULATE) != 0? FINISHED : (l > org) ? SUMMED : (SUMMED | FINISHED));
if (t.CompareAndSetPendingCount(b, b | state))
{
break;
}
}
double sum;
if (state != SUMMED)
{
int first;
if (l == org) // leftmost; no in
{
sum = a[org];
first = org + 1;
}
else
{
sum = t.@in;
first = l;
}
for (int i = first; i < h; ++i) // cumulate
{
a[i] = sum = fn.ApplyAsDouble(sum, a[i]);
}
}
else if (h < fnc) // skip rightmost
{
sum = a[l];
for (int i = l + 1; i < h; ++i) // sum only
{
sum = fn.ApplyAsDouble(sum, a[i]);
}
}
else
{
sum = t.@in;
}
t.@out = sum;
for (DoubleCumulateTask par;;) // propagate
{
if ((par = (DoubleCumulateTask)t.Completer) == null)
{
if ((state & FINISHED) != 0) // enable join
{
t.QuietlyComplete();
}
goto outerBreak;
}
int b = par.PendingCount;
if ((b & state & FINISHED) != 0)
{
t = par; // both done
}
else if ((b & state & SUMMED) != 0) // both summed
{
int nextState;
DoubleCumulateTask lt, rt;
if ((lt = par.left) != null && (rt = par.right) != null)
{
double lout = lt.@out;
par.@out = (rt.Hi == fnc ? lout : fn.ApplyAsDouble(lout, rt.@out));
}
int refork = (((b & CUMULATE) == 0 && par.lo == org) ? CUMULATE : 0);
if ((nextState = b | state | refork) == b || par.compareAndSetPendingCount(b, nextState))
{
state = SUMMED; // drop finished
t = par;
if (refork != 0)
{
par.fork();
}
}
}
else if (par.compareAndSetPendingCount(b, b | state))
{
goto outerBreak; // sib not ready
}
}
}
outerContinue :;
}
outerBreak :;
}