Use private core methods, perf test data

dotnet · Oct 5, 2017 · d3ac17e · d3ac17e
1 parent a6b0a37
commit d3ac17e
Showing 1 changed file with 54 additions and 23 deletions.
diff --git a/src/System.Runtime.Extensions/src/System/IO/StreamWriter.cs b/src/System.Runtime.Extensions/src/System/IO/StreamWriter.cs
@@ -398,9 +398,35 @@ public override void Write(char[] buffer, int index, int count)
             {
                 throw new ArgumentException(SR.Argument_InvalidOffLen);
             }
+            if (GetType() == typeof(StreamWriter))
+            {
+                WriteCore(new ReadOnlySpan<char>(buffer, index, count));
+            }
+            else
+            {
+                base.Write(buffer, index, count);
+            }
+        }
+
+        public override void Write(ReadOnlySpan<char> source)
+        {
+            if (GetType() == typeof(StreamWriter))
+            {
+                WriteCore(source);
+            }
+            else
+            {
+                base.Write(source);
+            }
+        }
 
+        private void WriteCore(ReadOnlySpan<char> source)
+        {
             CheckAsyncTaskInProgress();
 
+            int count = source.Length;
+            int index = 0;
+
             // Threshold of 4 was chosen after running perf tests
             if (count <= 4)
             {
@@ -412,7 +438,7 @@ public override void Write(char[] buffer, int index, int count)
                     }
 
                     Debug.Assert(_charLen - _charPos > 0, "StreamWriter::Write(char[]) isn't making progress!  This is most likely a race in user code.");
-                    _charBuffer[_charPos] = buffer[index];
+                    _charBuffer[_charPos] = source[index];
                     _charPos++;
                     index++;
                     count--;
@@ -434,7 +460,7 @@ public override void Write(char[] buffer, int index, int count)
                     }
 
                     Debug.Assert(n > 0, "StreamWriter::Write(char[], int, int) isn't making progress!  This is most likely a race condition in user code.");
-                    Buffer.BlockCopy(buffer, index * sizeof(char), _charBuffer, _charPos * sizeof(char), n * sizeof(char));
+                    source.Slice(index, n).CopyTo(new Span<char>(_charBuffer, _charPos, n));
                     _charPos += n;
                     index += n;
                     count -= n;
@@ -447,21 +473,6 @@ public override void Write(char[] buffer, int index, int count)
             }
         }
 
-        public override void Write(ReadOnlySpan<char> source)
-        {
-            char[] buffer = ArrayPool<char>.Shared.Rent(source.Length);
-
-            try
-            {
-                source.CopyTo(new Span<char>(buffer));
-                Write(buffer, 0, source.Length);
-            }
-            finally
-            {
-                ArrayPool<char>.Shared.Return(buffer);
-            }
-        }
-
         public override void Write(string value)
         {
             if (value == null)
@@ -529,6 +540,31 @@ public override void WriteLine(string value)
                 value = String.Empty;
             }
 
+            if (GetType() == typeof(StreamWriter))
+            {
+                WriteLineCore(value.AsSpan());
+            }
+            else
+            {
+                base.WriteLine(value);
+            }
+        }
+
+        public override void WriteLine(ReadOnlySpan<char> source)
+        {
+            if (GetType() == typeof(StreamWriter))
+            {
+                WriteLineCore(source);
+            }
+            else
+            {
+                base.WriteLine(source);
+            }
+
+        }
+
+        private void WriteLineCore(ReadOnlySpan<char> value)
+        {
             CheckAsyncTaskInProgress();
 
             int count = value.Length;
@@ -547,7 +583,7 @@ public override void WriteLine(string value)
                 }
 
                 Debug.Assert(n > 0, "StreamWriter::WriteLine(String) isn't making progress!  This is most likely a race condition in user code.");
-                value.CopyTo(index, _charBuffer, _charPos, n);
+                value.Slice(index, n).CopyTo(new Span<char>(_charBuffer, _charPos, n));
                 _charPos += n;
                 index += n;
                 count -= n;
@@ -571,11 +607,6 @@ public override void WriteLine(string value)
             }
         }
 
-        public override void WriteLine(ReadOnlySpan<char> source)
-        {
-            WriteLine(new string(source.ToArray()));
-        }
-
         #region Task based Async APIs
         public override Task WriteAsync(char value)
         {