diff --git a/src/mscorlib/shared/System/MemoryExtensions.Fast.cs b/src/mscorlib/shared/System/MemoryExtensions.Fast.cs
index d9e3af880482..d256887a9f7e 100644
--- a/src/mscorlib/shared/System/MemoryExtensions.Fast.cs
+++ b/src/mscorlib/shared/System/MemoryExtensions.Fast.cs
@@ -359,6 +359,7 @@ public static bool StartsWith(this ReadOnlySpan<char> span, ReadOnlySpan<char> v
         /// <summary>
         /// Creates a new span over the portion of the target array.
         /// </summary>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static Span<T> AsSpan<T>(this T[] array, int start)
         {
             if (array == null)
@@ -380,6 +381,7 @@ public static Span<T> AsSpan<T>(this T[] array, int start)
         /// </summary>
         /// <param name="text">The target string.</param>
         /// <remarks>Returns default when <paramref name="text"/> is null.</remarks>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static ReadOnlySpan<char> AsSpan(this string text)
         {
             if (text == null)
@@ -397,6 +399,7 @@ public static ReadOnlySpan<char> AsSpan(this string text)
         /// <exception cref="System.ArgumentOutOfRangeException">
         /// Thrown when the specified <paramref name="start"/> index is not in range (&lt;0 or &gt;text.Length).
         /// </exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static ReadOnlySpan<char> AsSpan(this string text, int start)
         {
             if (text == null)
@@ -422,6 +425,7 @@ public static ReadOnlySpan<char> AsSpan(this string text, int start)
         /// <exception cref="System.ArgumentOutOfRangeException">
         /// Thrown when the specified <paramref name="start"/> index or <paramref name="length"/> is not in range.
         /// </exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static ReadOnlySpan<char> AsSpan(this string text, int start, int length)
         {
             if (text == null)
diff --git a/src/mscorlib/shared/System/MemoryExtensions.cs b/src/mscorlib/shared/System/MemoryExtensions.cs
index 1a3b33acc701..c3e1cd51fa44 100644
--- a/src/mscorlib/shared/System/MemoryExtensions.cs
+++ b/src/mscorlib/shared/System/MemoryExtensions.cs
@@ -68,7 +68,6 @@ public static ReadOnlySpan<char> TrimEnd(this ReadOnlySpan<char> span)
         /// </summary>
         /// <param name="span">The source span from which the character is removed.</param>
         /// <param name="trimChar">The specified character to look for and remove.</param>
-        //[MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static ReadOnlySpan<char> Trim(this ReadOnlySpan<char> span, char trimChar)
         {
             return span.TrimStart(trimChar).TrimEnd(trimChar);
@@ -79,7 +78,6 @@ public static ReadOnlySpan<char> Trim(this ReadOnlySpan<char> span, char trimCha
         /// </summary>
         /// <param name="span">The source span from which the character is removed.</param>
         /// <param name="trimChar">The specified character to look for and remove.</param>
-        //[MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static ReadOnlySpan<char> TrimStart(this ReadOnlySpan<char> span, char trimChar)
         {
             int start = 0;
@@ -1204,7 +1202,7 @@ ref MemoryMarshal.GetReference(span),
         /// no larger element, the bitwise complement of <see cref="Span{T}.Length"/>.
         /// </returns>
         /// <exception cref="T:System.ArgumentNullException">
-		/// <paramref name = "comparable" /> is <see langword="null"/> .
+        /// <paramref name = "comparable" /> is <see langword="null"/> .
         /// </exception>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static int BinarySearch<T>(
@@ -1228,7 +1226,7 @@ public static int BinarySearch<T>(
         /// no larger element, the bitwise complement of <see cref="Span{T}.Length"/>.
         /// </returns>
         /// <exception cref="T:System.ArgumentNullException">
-		/// <paramref name = "comparable" /> is <see langword="null"/> .
+        /// <paramref name = "comparable" /> is <see langword="null"/> .
         /// </exception>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static int BinarySearch<T, TComparable>(
@@ -1278,7 +1276,7 @@ public static int BinarySearch<T, TComparer>(
         /// no larger element, the bitwise complement of <see cref="ReadOnlySpan{T}.Length"/>.
         /// </returns>
         /// <exception cref="T:System.ArgumentNullException">
-		/// <paramref name = "comparable" /> is <see langword="null"/> .
+        /// <paramref name = "comparable" /> is <see langword="null"/> .
         /// </exception>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static int BinarySearch<T>(
@@ -1302,7 +1300,7 @@ public static int BinarySearch<T>(
         /// no larger element, the bitwise complement of <see cref="ReadOnlySpan{T}.Length"/>.
         /// </returns>
         /// <exception cref="T:System.ArgumentNullException">
-		/// <paramref name = "comparable" /> is <see langword="null"/> .
+        /// <paramref name = "comparable" /> is <see langword="null"/> .
         /// </exception>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static int BinarySearch<T, TComparable>(
diff --git a/src/mscorlib/shared/System/String.cs b/src/mscorlib/shared/System/String.cs
index a1251d6be0e9..42d21ba06870 100644
--- a/src/mscorlib/shared/System/String.cs
+++ b/src/mscorlib/shared/System/String.cs
@@ -360,6 +360,7 @@ public static string Create<TState>(int length, TState state, SpanAction<char, T
             return result;
         }
 
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static implicit operator ReadOnlySpan<char>(string value) =>
             value != null ? new ReadOnlySpan<char>(ref value.GetRawStringData(), value.Length) : default;