Performance improvements

PerfectNumbers.Core/Gpu/GpuUInt128.cs

@@ -393,25 +393,22 @@ public struct GpuUInt128 : IComparable<GpuUInt128>, IEquatable<GpuUInt128>
 
         ulong w1 = xLow * yHigh;
         ulong w2 = xHigh * yLow;
-        return (xHigh * yHigh) + (w1 >> 32) + (w2 >> 32) +
-        (
-            (
-                ((xLow * yLow) >> 32) +
-                (uint)w1 +
-                (uint)w2
-            ) >> 32
-        );
+        ulong w3 = xLow * yLow;
+
+        ulong result = (xHigh * yHigh) + (w1 >> 32) + (w2 >> 32);
+        result += ((w3 >> 32) + (uint)w1 + (uint)w2) >> 32;
+        return result;
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public void Mul64(GpuUInt128 other)
     {
         // Multiply this.Low (assumed 64-bit value) by full 128-bit other
-        ulong operand = Low,
-              otherLow = other.Low;
-              
-        Low = operand * otherLow;
-        High = operand * other.High + MulHigh(operand, otherLow);
+        ulong operand = Low;
+            //   otherLow = other.Low;
+
+        Low = operand * other.Low;
+        High = operand * other.High + MulHigh(operand, other.Low);
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]