1 files changed, 18 insertions, 0 deletions
diff --git a/crypto/src/math/ec/custom/sec/SecT409Field.cs b/crypto/src/math/ec/custom/sec/SecT409Field.cs
index 0fb7377f6..414a094a8 100644
--- a/crypto/src/math/ec/custom/sec/SecT409Field.cs
+++ b/crypto/src/math/ec/custom/sec/SecT409Field.cs
@@ -1,5 +1,9 @@
 using System;
 using System.Diagnostics;
+#if NETCOREAPP3_0_OR_GREATER
+using System.Runtime.Intrinsics;
+using System.Runtime.Intrinsics.X86;
+#endif
 
 using Org.BouncyCastle.Math.Raw;
 
@@ -344,6 +348,20 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec
             Debug.Assert(x >> 59 == 0);
             Debug.Assert(y >> 59 == 0);
 
+#if NETCOREAPP3_0_OR_GREATER
+            if (Pclmulqdq.IsSupported)
+            {
+                var X = Vector128.CreateScalar(x);
+                var Y = Vector128.CreateScalar(y);
+                var Z = Pclmulqdq.CarrylessMultiply(X, Y, 0x00);
+                ulong z0 = Z.GetElement(0);
+                ulong z1 = Z.GetElement(1);
+                z[zOff    ] ^= z0 & M59;
+                z[zOff + 1] ^= (z0 >> 59) ^ (z1 << 5);
+                return;
+            }
+#endif
+
             //u[0] = 0;
             u[1] = y;
             u[2] = u[1] << 1;