Accelerate Mersenne modular multiplication paths

PerfectNumbers.Core/UIntExtensions.cs

@@ -4,99 +4,26 @@ namespace PerfectNumbers.Core;
 
 public static class UIntExtensions
 {
-    private static readonly byte[] Mod6Lookup = { 0, 3, 4, 1, 2, 5 };
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static uint Mod3(this uint value) => value % 3U;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public static uint Mod3(this uint value)
-    {
-        ulong wideValue = 0UL;
-        uint quotient = 0U;
-        uint remainder = 0U;
-
-        wideValue = (ulong)value * 0xAAAAAAABUL;
-        quotient = (uint)(wideValue >> 33);
-        remainder = value - quotient * 3U;
-
-        return remainder;
-    }
+    public static uint Mod5(this uint value) => value % 5U;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public static uint Mod5(this uint value)
-    {
-        ulong wideValue = 0UL;
-        uint quotient = 0U;
-        uint remainder = 0U;
-
-        wideValue = (ulong)value * 0xCCCCCCCDUL;
-        quotient = (uint)(wideValue >> 34);
-        remainder = value - quotient * 5U;
-
-        return remainder;
-    }
+    public static uint Mod6(this uint value) => value % 6U;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public static uint Mod6(this uint value)
-    {
-        return Mod6Lookup[(int)(((value.Mod3() << 1) | (value & 1U)))];
-    }
-
-    [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public static uint Mod7(this uint value)
-    {
-        uint remainder = 0U;
-        uint temp = 0U;
-        uint chunk = 0U;
-
-        temp = value;
-        while (temp != 0U)
-        {
-            chunk = temp & 7U;
-            remainder += chunk;
-            temp >>= 3;
-            if (remainder >= 7U)
-            {
-                remainder -= 7U;
-            }
-        }
-
-        return remainder >= 7U ? remainder - 7U : remainder;
-    }
+    public static uint Mod7(this uint value) => value % 7U;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static uint Mod8(this uint value) => value & 7U;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public static uint Mod10(this uint value)
-    {
-        ulong wideValue = 0UL;
-        uint quotient = 0U;
-        uint remainder = 0U;
-
-        wideValue = (ulong)value * 0xCCCCCCCDUL;
-        quotient = (uint)(wideValue >> 35);
-        remainder = value - quotient * 10U;
-
-        return remainder;
-    }
+    public static uint Mod10(this uint value) => value % 10U;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public static uint Mod11(this uint value)
-    {
-        uint remainder = 0U;
-        uint temp = 0U;
-        uint chunk = 0U;
-
-        temp = value;
-        while (temp != 0U)
-        {
-            chunk = temp & 1023U;
-            remainder += chunk;
-            temp >>= 10;
-            remainder -= 11U * (remainder / 11U);
-        }
-
-        return remainder;
-    }
+    public static uint Mod11(this uint value) => value % 11U;
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public static uint Mod128(this uint value) => value & 127U;