Fix the sys::Path::getSuffix() implementation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52288 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/System/Win32/Path.inc b/lib/System/Win32/Path.inc
index b5897053..8f33664 100644
--- a/lib/System/Win32/Path.inc
+++ b/lib/System/Win32/Path.inc
@@ -259,6 +259,22 @@
     return path.substr(slash, dot - slash);
 }
 
+std::string
+Path::getSuffix() const {
+  // Find the last slash
+  size_t slash = path.rfind('/');
+  if (slash == std::string::npos)
+    slash = 0;
+  else
+    slash++;
+
+  size_t dot = path.rfind('.');
+  if (dot == std::string::npos || dot < slash)
+    return std::string();
+  else
+    return path.substr(dot + 1);
+}
+
 bool
 Path::exists() const {
   DWORD attr = GetFileAttributes(path.c_str());