stackalloc for BytesToDecimal (#31190)

dotnet · Jan 25, 2024 · 31bd863 · 31bd863
1 parent 7be0b85
commit 31bd863
Showing 1 changed file with 10 additions and 11 deletions.
diff --git a/src/EFCore/Storage/ValueConversion/NumberToBytesConverter.cs b/src/EFCore/Storage/ValueConversion/NumberToBytesConverter.cs
@@ -299,23 +299,22 @@ private static readonly MethodInfo ToDecimalMethod
     [EntityFrameworkInternal]
     public static decimal BytesToDecimal(byte[] bytes)
     {
-        var gotBytes = bytes;
+        Span<byte> gotBytes = BitConverter.IsLittleEndian ? stackalloc byte[16] : bytes;
         if (BitConverter.IsLittleEndian)
         {
-            gotBytes = new byte[16];
-            Array.Copy(bytes, gotBytes, 16);
-            Array.Reverse(gotBytes, 0, 4);
-            Array.Reverse(gotBytes, 4, 4);
-            Array.Reverse(gotBytes, 8, 4);
-            Array.Reverse(gotBytes, 12, 4);
+            bytes.CopyTo(gotBytes);
+            gotBytes.Slice(0, 4).Reverse();
+            gotBytes.Slice(4, 4).Reverse();
+            gotBytes.Slice(8, 4).Reverse();
+            gotBytes.Slice(12, 4).Reverse();
         }
 
-        var specialBits = BitConverter.ToUInt32(gotBytes, 0);
+        var specialBits = BitConverter.ToUInt32(gotBytes);
 
         return new decimal(
-            BitConverter.ToInt32(gotBytes, 12),
-            BitConverter.ToInt32(gotBytes, 8),
-            BitConverter.ToInt32(gotBytes, 4),
+            BitConverter.ToInt32(gotBytes.Slice(12)),
+            BitConverter.ToInt32(gotBytes.Slice(8)),
+            BitConverter.ToInt32(gotBytes.Slice(4)),
             (specialBits & 0x80000000) != 0,
             (byte)((specialBits & 0x00FF0000) >> 16));
     }