diff --git a/tests/DeviceLooperTest.cpp b/tests/DeviceLooperTest.cpp
new file mode 100644
index 0000000..1520900
--- /dev/null
+++ b/tests/DeviceLooperTest.cpp
@@ -0,0 +1,141 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "Test.h"
+#include "SkDeviceLooper.h"
+#include "SkRasterClip.h"
+
+static void make_bm(SkBitmap* bm, int w, int h) {
+    bm->setConfig(SkBitmap::kA8_Config, w, h);
+    bm->allocPixels();
+}
+
+static bool equal(const SkRasterClip& a, const SkRasterClip& b) {
+    if (a.isBW()) {
+        return b.isBW() && a.bwRgn() == b.bwRgn();
+    } else {
+        return a.isAA() && a.aaRgn() == b.aaRgn();
+    }
+}
+
+static void test_simple(skiatest::Reporter* reporter) {
+    struct {
+        SkISize fDevSize;
+        SkIRect fRCBounds;
+        SkIRect fRect;
+    } const gRec[] = {
+        { { 4000, 10 }, { 0, 0, 4000, 10 }, { 0, 0, 4000, 4000 } },
+        { { 10, 4000 }, { 0, 0, 10, 4000 }, { 0, 0, 4000, 4000 } },
+        // very large devce, small rect
+        { { 32000, 10 }, { 0, 0, 32000, 10 }, { 0, 0, 4000, 4000 } },
+        { { 10, 32000 }, { 0, 0, 10, 32000 }, { 0, 0, 4000, 4000 } },
+        // very large device, small clip
+        { { 32000, 10 }, { 0, 0, 4000, 10 }, { 0, 0, 32000, 32000 } },
+        { { 10, 32000 }, { 0, 0, 10, 4000 }, { 0, 0, 32000, 32000 } },
+    };
+    
+    for (size_t i = 0; i < SK_ARRAY_COUNT(gRec); ++i) {
+        SkBitmap bitmap;
+        make_bm(&bitmap, gRec[i].fDevSize.width(), gRec[i].fDevSize.height());
+        
+        SkRasterClip rc(gRec[i].fRCBounds);
+        
+        for (int aa = 0; aa <= 1; ++aa) {
+            SkDeviceLooper looper(bitmap, rc, gRec[i].fRect, SkToBool(aa));
+            
+            bool valid = looper.next();
+            REPORTER_ASSERT(reporter, valid);
+            if (valid) {
+                REPORTER_ASSERT(reporter, looper.getBitmap().width() == bitmap.width());
+                REPORTER_ASSERT(reporter, looper.getBitmap().height() == bitmap.height());
+                REPORTER_ASSERT(reporter, equal(looper.getRC(), rc));
+                
+                REPORTER_ASSERT(reporter, !looper.next());
+            }
+        }
+        // test that a rect that doesn't intersect returns no loops
+        {
+            SkIRect r = rc.getBounds();
+            r.offset(r.width(), 0);
+            SkDeviceLooper looper(bitmap, rc, r, false);
+            REPORTER_ASSERT(reporter, !looper.next());
+        }
+    }
+}
+
+// mask-bits are interpreted as the areas where the clip is visible
+//  [ 0x01  0x02 ]
+//  [ 0x04  0x08 ]
+//
+static void make_rgn(SkRegion* rgn, int w, int h, unsigned mask) {
+    SkASSERT(SkAlign2(w));
+    SkASSERT(SkAlign2(h));
+    w >>= 1;
+    h >>= 1;
+    const SkIRect baseR = SkIRect::MakeWH(w, h);
+
+    int bit = 1;
+    for (int y = 0; y <= 1; ++y) {
+        for (int x = 0; x <= 1; ++x) {
+            if (mask & bit) {
+                SkIRect r = baseR;
+                r.offset(x * w, y * h);
+                rgn->op(r, SkRegion::kUnion_Op);
+            }
+            bit <<= 1;
+        }
+    }
+}
+
+static void test_complex(skiatest::Reporter* reporter) {
+    // choose size values that will result in 4 quadrants, given fAA setting
+    const int BW_SIZE = 17 * 1000;
+    const int AA_SIZE = 7 * 1000;
+
+    struct {
+        SkISize fSize;
+        bool    fAA;
+    } const gRec[] = {
+        { { BW_SIZE, BW_SIZE }, false },
+        { {  AA_SIZE, AA_SIZE }, true },
+    };
+    
+    for (size_t i = 0; i < SK_ARRAY_COUNT(gRec); ++i) {
+        const int w = gRec[i].fSize.width();
+        const int h = gRec[i].fSize.height();
+
+        SkBitmap bitmap;
+        make_bm(&bitmap, w, h);
+
+        const SkIRect rect = SkIRect::MakeWH(w, h);
+
+        // mask-bits are interpreted as the areas where the clip is visible
+        //  [ 0x01  0x02 ]
+        //  [ 0x04  0x08 ]
+        //
+        for (int mask = 0; mask <= 15; ++mask) {
+            SkRegion rgn;
+            make_rgn(&rgn, w, h, mask);
+
+            SkRasterClip rc;
+            rc.op(rgn, SkRegion::kReplace_Op);
+
+            SkDeviceLooper looper(bitmap, rc, rect, gRec[i].fAA);
+            while (looper.next()) {
+                REPORTER_ASSERT(reporter, !looper.getRC().isEmpty());
+            }
+        }
+    }
+}
+
+static void TestDeviceLooper(skiatest::Reporter* reporter) {
+    test_simple(reporter);
+    test_complex(reporter);
+}
+
+#include "TestClassDef.h"
+DEFINE_TESTCLASS("DeviceLooper", DeviceLooperClass, TestDeviceLooper)