Use optimized hash creation methods on .NET 5+

dotnet · Apr 27, 2023 · bb641e1 · bb641e1
1 parent 663ceb3
commit bb641e1
Showing 1 changed file with 44 additions and 0 deletions.
diff --git a/src/Workspaces/Core/Portable/Workspace/Solution/Checksum_Factory.cs b/src/Workspaces/Core/Portable/Workspace/Solution/Checksum_Factory.cs
@@ -34,6 +34,19 @@ internal partial class Checksum
 
         public static Checksum Create(IEnumerable<string> values)
         {
+#if NET5_0_OR_GREATER
+            using var pooledHash = s_incrementalHashPool.GetPooledObject();
+
+            foreach (var value in values)
+            {
+                pooledHash.Object.AppendData(MemoryMarshal.AsBytes(value.AsSpan()));
+                pooledHash.Object.AppendData(MemoryMarshal.AsBytes("\0".AsSpan()));
+            }
+
+            Span<byte> hash = stackalloc byte[SHA256HashSizeBytes];
+            pooledHash.Object.GetHashAndReset(hash);
+            return From(hash);
+#else
             using var pooledHash = s_incrementalHashPool.GetPooledObject();
             using var pooledBuffer = SharedPools.ByteArray.GetPooledObject();
             var hash = pooledHash.Object;
@@ -45,21 +58,51 @@ public static Checksum Create(IEnumerable<string> values)
             }
 
             return From(hash.GetHashAndReset());
+#endif
         }
 
         public static Checksum Create(string value)
         {
+#if NET5_0_OR_GREATER
+            Span<byte> hash = stackalloc byte[SHA256HashSizeBytes];
+            SHA256.HashData(MemoryMarshal.AsBytes(value.AsSpan()), hash);
+            return From(hash);
+#else
             using var pooledHash = s_incrementalHashPool.GetPooledObject();
             using var pooledBuffer = SharedPools.ByteArray.GetPooledObject();
             var hash = pooledHash.Object;
 
             AppendData(hash, pooledBuffer.Object, value);
 
             return From(hash.GetHashAndReset());
+#endif
         }
 
         public static Checksum Create(Stream stream)
         {
+#if NET7_0_OR_GREATER
+            Span<byte> hash = stackalloc byte[SHA256HashSizeBytes];
+            SHA256.HashData(stream, hash);
+            return From(hash);
+#elif NET5_0_OR_GREATER
+            using var pooledHash = s_incrementalHashPool.GetPooledObject();
+            Span<byte> buffer = stackalloc byte[SharedPools.ByteBufferSize];
+
+            int bytesRead;
+            do
+            {
+                bytesRead = stream.Read(buffer);
+                if (bytesRead > 0)
+                {
+                    pooledHash.Object.AppendData(buffer[..bytesRead]);
+                }
+            }
+            while (bytesRead > 0);
+
+            Span<byte> hash = stackalloc byte[SHA256HashSizeBytes];
+            pooledHash.Object.GetHashAndReset(hash);
+            return From(hash);
+#else
             using var pooledHash = s_incrementalHashPool.GetPooledObject();
             using var pooledBuffer = SharedPools.ByteArray.GetPooledObject();
 
@@ -91,6 +134,7 @@ public static Checksum Create(Stream stream)
             // hash algorithm used here should remain functionally correct even
             // after the truncation
             return From(bytes);
+#endif
         }
 
         public static Checksum Create(IObjectWritable @object)