/// <summary>
/// A simple 1D kernel using a custom atomic implementation
/// of Atomic.Add(ArrayView<double>, double) that leverages pre-defined
/// compare-exchange functionality for doubles.
/// <param name="index">The current thread index.</param>
/// <param name="dataView">The view pointing to our memory buffer.</param>
/// <param name="value">The value to add.</param>
static void AddDoubleAtomicILGPUFunctionsKernel(
Index1 index,
ArrayView <double> dataView,
double value)
{
// atomic add: dataView[0] += value;
Atomic.MakeAtomic(
ref dataView[0],
value,
new AddDoubleOperation(),
new CompareExchangeDouble());
}
/// <summary>
/// A simple 1D kernel using a custom atomic implementation
/// of Atomic.Add(ArrayView<double>, double)
/// <param name="index">The current thread index.</param>
/// <param name="dataView">The view pointing to our memory buffer.</param>
/// <param name="value">The value to add.</param>
static void AddDoubleAtomicKernel(
Index index,
ArrayView <double> dataView,
double value)
{
// atomic add: dataView[0] += value;
Atomic.MakeAtomic(
dataView.GetVariableView(0),
value,
new AddDoubleOperation(),
new DoubleCompareExchangeOperation());
}
private static void ShrinkKernel(Index2 index,
ArrayView2D <float> xImage,
ArrayView2D <float> bMap,
ArrayView2D <float> aMap,
ArrayView <float> lambdaAlpha,
ArrayView <Pixel> output)
{
if (index.X == 0 & index.Y == 0)
{
output[0].AbsDiff = 0;
}
if (index.InBounds(xImage.Extent))
{
var xOld = xImage[index];
var gradient = bMap[index];
var lipschitz = aMap[index];
var lambda = lambdaAlpha[0];
var alpha = lambdaAlpha[1];
var xNew = GPUProximalOperator(xOld * lipschitz + gradient, lipschitz, lambda, alpha);
var xAbsDiff = XMath.Abs(xNew - xOld);
var xIndex = index.X;
var yIndex = index.Y;
var sign = XMath.Sign(xNew - xOld);
var pix = new Pixel()
{
AbsDiff = xAbsDiff,
X = xIndex,
Y = yIndex,
Sign = sign
};
Atomic.MakeAtomic(ref output[0], pix, new MaxPixelOperation(), new PixelCompareExchange());
}
}
/// <summary>
/// A software implementation for atomic adds on 64-bit floats.
/// </summary>
/// <param name="target">The target address.</param>
/// <param name="value">The value to add.</param>
private static double AtomicAddF64(ref double target, double value) =>
Atomic.MakeAtomic(
ref target,
value,
new AddDouble(),
new CompareExchangeDouble());
private static float AtomicAddF32(ref float target, float value) =>
Atomic.MakeAtomic(
ref target,
value,
new AddFloat(),
new CompareExchangeFloat());
