IndexOf(char, Ordinal) use fast path (dotnet/coreclr#19788)

Commit migrated from https://github.com/dotnet/coreclr/commit/f597da2dd522ca1ca7293ef83798aae86840e588

diff --git a/src/libraries/System.Private.CoreLib/src/System/String.Searching.cs b/src/libraries/System.Private.CoreLib/src/System/String.Searching.cs
index 56549d8..857d64e 100644 (file)
--- a/src/libraries/System.Private.CoreLib/src/System/String.Searching.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/String.Searching.cs
@@ -55,7 +55,7 @@ namespace System
                     return CompareInfo.Invariant.IndexOf(this, value, GetCaseCompareOfComparisonCulture(comparisonType));
 
                 case StringComparison.Ordinal:
-                    return CompareInfo.Invariant.IndexOf(this, value, CompareOptions.Ordinal);
+                    return IndexOf(value);
 
                 case StringComparison.OrdinalIgnoreCase:
                     return CompareInfo.Invariant.IndexOf(this, value, CompareOptions.OrdinalIgnoreCase);