--- a/jdk/src/share/native/sun/font/layout/LayoutEngine.cpp	Mon Mar 07 17:23:39 2011 -0800
+++ b/jdk/src/share/native/sun/font/layout/LayoutEngine.cpp	Mon Mar 07 19:37:07 2011 -0800
@@ -251,6 +251,10 @@
         return 0;
     }
 
+    if ((fTypoFlags & 0x4) == 0) { // no canonical processing
+      return count;
+    }
+
     const GlyphSubstitutionTableHeader *canonGSUBTable = (GlyphSubstitutionTableHeader *) CanonShaping::glyphSubstitutionTable;
     LETag scriptTag  = OpenTypeLayoutEngine::getScriptTag(fScriptCode);
     LETag langSysTag = OpenTypeLayoutEngine::getLangSysTag(fLanguageCode);

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/awt/font/TextLayout/CombiningPerf.java	Mon Mar 07 19:37:07 2011 -0800
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 6328154 6962082
+ * @summary ensure that ascii, and latin-1 text without combining marks, both layout faster
+ *  than latin-1 text with combining marks.  The presumption is then that the canonical
+ *  GSUB table is being run only on the latter and not on either of the former.
+ */
+
+import java.awt.Font;
+import java.awt.GraphicsEnvironment;
+import java.awt.font.FontRenderContext;
+import java.awt.font.TextLayout;
+
+import static java.awt.Font.*;
+
+public class CombiningPerf {
+    private static Font font;
+    private static FontRenderContext frc;
+
+    public static void main(String[] args) throws Exception {
+        System.err.println("start");
+
+        GraphicsEnvironment.getLocalGraphicsEnvironment();
+
+        font = new Font("Lucida Sans Regular", PLAIN, 12);
+        frc = new FontRenderContext(null, false, false);
+
+        String ascii = "the characters are critical noodles?";
+        String french = "l'aper\u00e7u caract\u00e8re one \u00e9t\u00e9 cr\u00e9\u00e9s";
+        String frenchX = "l'aper\u00e7u caracte\u0300re one e\u0301te\u0301 ere\u0301e\u0301s";
+
+        // warmup
+        for (int i = 0; i < 100; ++i) {
+            TextLayout tl = new TextLayout(french, font, frc);
+            tl = new TextLayout(ascii, font, frc);
+            tl = new TextLayout(frenchX, font, frc);
+        }
+        /**/
+        long atime = test(ascii);
+        System.err.println("atime: " + (atime/1000000.0) + " length: " + ascii.length());
+
+        long ftime = test(french);
+        System.err.println("ftime: " + (ftime/1000000.0) + " length: " + french.length());
+
+        long xtime = test(frenchX);
+        System.err.println("xtime: " + (xtime/1000000.0) + " length: " + frenchX.length());
+
+        long limit = xtime * 2 / 3;
+        if (atime > limit || ftime > limit) {
+            throw new Exception("took too long");
+        }
+        /**/
+    }
+
+    private static long test(String text) {
+        long start = System.nanoTime();
+        for (int i = 0; i < 2000; ++i) {
+            TextLayout tl = new TextLayout(text, font, frc);
+        }
+        return System.nanoTime() - start;
+    }
+}