diff -r 000000000000 -r 6474c204b198 gfx/tests/gtest/gfxTextRunPerfTest.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/tests/gtest/gfxTextRunPerfTest.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,120 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "gtest/gtest.h"
+
+#include "mozilla/ArrayUtils.h"
+
+#include "nsCOMPtr.h"
+#include "nsTArray.h"
+#include "nsString.h"
+#include "nsDependentString.h"
+
+#include "prinrval.h"
+
+#include "gfxContext.h"
+#include "gfxFont.h"
+#include "gfxPlatform.h"
+
+#include "gfxFontTest.h"
+
+using namespace mozilla;
+
+struct TestEntry {
+  const char* mFamilies;
+  const char* mString;
+};
+
+TestEntry testList[] = {
+#include "per-word-runs.h"
+{ nullptr, nullptr } // terminator
+};
+
+static already_AddRefed<gfxContext>
+MakeContext ()
+{
+    const int size = 200;
+
+    nsRefPtr<gfxASurface> surface;
+
+    surface = gfxPlatform::GetPlatform()->
+        CreateOffscreenSurface(IntSize(size, size),
+                               gfxASurface::ContentFromFormat(gfxImageFormat::RGB24));
+    nsRefPtr<gfxContext> ctx = new gfxContext(surface);
+    return ctx.forget();
+}
+
+const char* lastFamilies = nullptr;
+
+static void
+RunTest (TestEntry *test, gfxContext *ctx) {
+    nsRefPtr<gfxFontGroup> fontGroup;
+    if (!lastFamilies || strcmp(lastFamilies, test->mFamilies)) {
+        gfxFontStyle style_western_normal_16 (mozilla::gfx::FontStyle::NORMAL,
+                                              400,
+                                              0,
+                                              16.0,
+                                              NS_NewPermanentAtom(NS_LITERAL_STRING("en")),
+                                              0.0,
+                                              false, false,
+                                              NS_LITERAL_STRING(""));
+
+        fontGroup = gfxPlatform::GetPlatform()->CreateFontGroup(NS_ConvertUTF8toUTF16(test->mFamilies), &style_western_normal_16, nullptr);
+    }
+
+    nsAutoPtr<gfxTextRun> textRun;
+    uint32_t i;
+    bool isASCII = true;
+    for (i = 0; test->mString[i]; ++i) {
+        if (test->mString[i] & 0x80) {
+            isASCII = false;
+        }
+    }
+    gfxTextRunFactory::Parameters params = {
+      ctx, nullptr, nullptr, nullptr, 0, 60
+    };
+    uint32_t flags = gfxTextRunFactory::TEXT_IS_PERSISTENT;
+    uint32_t length;
+    gfxFontTestStore::NewStore();
+    if (isASCII) {
+        flags |= gfxTextRunFactory::TEXT_IS_ASCII |
+                 gfxTextRunFactory::TEXT_IS_8BIT;
+        length = strlen(test->mString);
+        textRun = fontGroup->MakeTextRun(reinterpret_cast<const uint8_t*>(test->mString), length, &params, flags);
+    } else {
+        NS_ConvertUTF8toUTF16 str(nsDependentCString(test->mString));
+        length = str.Length();
+        textRun = fontGroup->MakeTextRun(str.get(), length, &params, flags);
+    }
+
+    // Should we test drawing?
+    // textRun->Draw(ctx, gfxPoint(0,0), 0, length, nullptr, nullptr, nullptr);
+
+    textRun->GetAdvanceWidth(0, length, nullptr);
+    gfxFontTestStore::DeleteStore();
+}
+
+uint32_t iterations = 1;
+
+TEST(Gfx, TextRunPref) {
+    nsRefPtr<gfxContext> context = MakeContext();
+
+    // Start timing
+    PRIntervalTime start = PR_IntervalNow();
+
+    for (uint32_t i = 0; i < iterations; ++i) {
+        for (uint test = 0;
+             test < ArrayLength(testList) - 1;
+             test++)
+        {
+            RunTest(&testList[test], context);
+        }
+    }
+
+    PRIntervalTime end = PR_IntervalNow();
+
+    printf("Elapsed time (ms): %d\n", PR_IntervalToMilliseconds(end - start));
+
+}