From 5a7c950b899948d00e5e0aeab61fd4c517e45906 Mon Sep 17 00:00:00 2001
From: FPtje <none@none>
Date: Thu, 5 Nov 2015 19:56:42 +0100
Subject: Small optimisation in CItem::GetExtension()

The profiler indicates that this function is the end of a hot path in the
visualisation. @assarbad mentioned earlier that CStrings are slow, and with this
 commit we confirm that.
---
 windirstat/item.cpp | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/windirstat/item.cpp b/windirstat/item.cpp
index e4f188c..89a128e 100644
--- a/windirstat/item.cpp
+++ b/windirstat/item.cpp
@@ -914,18 +914,22 @@ CString CItem::GetExtension() const
 
     CString ext;
 
+    CString name = GetName();
+
     switch (GetType())
     {
     case IT_FILE:
         {
-            int i = GetName().ReverseFind(wds::chrDot);
+            int i = name.ReverseFind(wds::chrDot);
             if(i == -1)
             {
                 ext = _T(".");
             }
             else
             {
-                ext = GetName().Mid(i);
+                // Faster than name.Mid(i);
+                LPCTSTR alpha = static_cast<LPCTSTR>(name);
+                ext = &alpha[i];
             }
             ext.MakeLower();
             break;
@@ -933,7 +937,7 @@ CString CItem::GetExtension() const
     case IT_FREESPACE:
     case IT_UNKNOWN:
         {
-            ext = GetName();
+            ext = name;
         }
         break;
 
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