From: James Ko <jamesqko@gmail.com>
Date: Thu, 18 Feb 2016 03:41:42 +0000 (-0500)
Subject: Optimize String.Replace when the chars are the same
X-Git-Tag: accepted/tizen/base/20180629.140029~5532^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=351091dcb99061d735cc2792139e737a8ead93dd;p=platform%2Fupstream%2Fcoreclr.git

Optimize String.Replace when the chars are the same
---

diff --git a/src/classlibnative/bcltype/stringnative.cpp b/src/classlibnative/bcltype/stringnative.cpp
index 311be11..554e0b9 100644
--- a/src/classlibnative/bcltype/stringnative.cpp
+++ b/src/classlibnative/bcltype/stringnative.cpp
@@ -686,6 +686,15 @@ FCIMPL3(LPVOID, COMString::Replace, StringObject* thisRefUNSAFE, CLR_CHAR oldCha
     }
 
     //Perf: If no replacements required, return initial reference
+    
+    // Do it if the chars are the same...
+    
+    if ((WCHAR)oldChar == (WCHAR)newChar)
+    {
+        return thisRefUNSAFE;
+    }
+    
+    // Or if the old char isn't found.
     oldBuffer = thisRef->GetBuffer();
     length = thisRef->GetStringLength();