diff --git a/test/624-checker-stringops/src/Main.java b/test/624-checker-stringops/src/Main.java
new file mode 100644
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+++ b/test/624-checker-stringops/src/Main.java
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Tests properties of some string operations represented by intrinsics.
+ */
+public class Main {
+
+  static final String ABC = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+  static final String XYZ = "XYZ";
+
+  //
+  // Variant intrinsics remain in the loop, but invariant references are hoisted out of the loop.
+  //
+  /// CHECK-START: int Main.liveIndexOf() licm (before)
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOf            loop:{{B\d+}} outer_loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOfAfter       loop:{{B\d+}} outer_loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOf      loop:{{B\d+}} outer_loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOfAfter loop:{{B\d+}} outer_loop:none
+  //
+  /// CHECK-START: int Main.liveIndexOf() licm (after)
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOf            loop:{{B\d+}} outer_loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOfAfter       loop:{{B\d+}} outer_loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOf      loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOfAfter loop:none
+  static int liveIndexOf() {
+    int k = ABC.length() + XYZ.length();  // does LoadString before loops
+    for (char c = 'A'; c <= 'Z'; c++) {
+      k += ABC.indexOf(c);
+    }
+    for (char c = 'A'; c <= 'Z'; c++) {
+      k += ABC.indexOf(c, 4);
+    }
+    for (char c = 'A'; c <= 'Z'; c++) {
+      k += ABC.indexOf(XYZ);
+    }
+    for (char c = 'A'; c <= 'Z'; c++) {
+      k += ABC.indexOf(XYZ, 2);
+    }
+    return k;
+  }
+
+  //
+  // All dead intrinsics can be removed completely.
+  //
+  /// CHECK-START: int Main.deadIndexOf() dead_code_elimination$initial (before)
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOf            loop:{{B\d+}} outer_loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringIndexOfAfter       loop:{{B\d+}} outer_loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOf      loop:{{B\d+}} outer_loop:none
+  /// CHECK-DAG: InvokeVirtual intrinsic:StringStringIndexOfAfter loop:{{B\d+}} outer_loop:none
+  //
+  /// CHECK-START: int Main.deadIndexOf() dead_code_elimination$initial (after)
+  /// CHECK-NOT: InvokeVirtual intrinsic:StringIndexOf
+  /// CHECK-NOT: InvokeVirtual intrinsic:StringIndexOfAfter
+  /// CHECK-NOT: InvokeVirtual intrinsic:StringStringIndexOf
+  /// CHECK-NOT: InvokeVirtual intrinsic:StringStringIndexOfAfter
+  static int deadIndexOf() {
+    int k = ABC.length() + XYZ.length();  // does LoadString before loops
+    for (char c = 'A'; c <= 'Z'; c++) {
+      int d = ABC.indexOf(c);
+    }
+    for (char c = 'A'; c <= 'Z'; c++) {
+      int d = ABC.indexOf(c, 4);
+    }
+    for (char c = 'A'; c <= 'Z'; c++) {
+      int d = ABC.indexOf(XYZ);
+    }
+    for (char c = 'A'; c <= 'Z'; c++) {
+      int d = ABC.indexOf(XYZ, 2);
+    }
+    return k;
+  }
+
+  //
+  // Explicit null check on receiver, implicit null check on argument prevents hoisting.
+  //
+  /// CHECK-START: int Main.indexOfExceptions(java.lang.String, java.lang.String) licm (after)
+  /// CHECK-DAG: <<String:l\d+>> NullCheck                                                         loop:<<Loop:B\d+>> outer_loop:none
+  /// CHECK-DAG:                 InvokeVirtual [<<String>>,{{l\d+}}] intrinsic:StringStringIndexOf loop:<<Loop>>      outer_loop:none
+  static int indexOfExceptions(String s, String t) {
+    int k = 0;
+    for (char c = 'A'; c <= 'Z'; c++) {
+      k += s.indexOf(t);
+    }
+    return k;
+  }
+
+  public static void main(String[] args) {
+    expectEquals(1865, liveIndexOf());
+    expectEquals(29, deadIndexOf());
+    try {
+      indexOfExceptions(null, XYZ);
+      throw new Error("Expected: NPE");
+    } catch (NullPointerException e) {
+    }
+    try {
+      indexOfExceptions(ABC, null);
+      throw new Error("Expected: NPE");
+    } catch (NullPointerException e) {
+    }
+    expectEquals(598, indexOfExceptions(ABC, XYZ));
+
+    System.out.println("passed");
+  }
+
+  private static void expectEquals(int expected, int result) {
+    if (expected != result) {
+      throw new Error("Expected: " + expected + ", found: " + result);
+    }
+  }
+}