8035828: Turn on @Stable support in VM

Reviewed-by: jrose, twisti

hotspot/src/share/vm/opto/c2_globals.hpp

@@ -452,7 +452,7 @@
   product(bool, EliminateAutoBox, true,                                     \
           "Control optimizations for autobox elimination")                  \
                                                                             \
-  experimental(bool, UseImplicitStableValues, false,                        \
+  diagnostic(bool, UseImplicitStableValues, true,                           \
           "Mark well-known stable fields as such (e.g. String.value)")      \
                                                                             \
   product(intx, AutoBoxCacheMax, 128,                                       \

hotspot/src/share/vm/runtime/globals.hpp

@@ -3799,8 +3799,8 @@ class CommandLineFlags {
   experimental(bool, TrustFinalNonStaticFields, false,                      \
           "trust final non-static declarations for constant folding")       \
                                                                             \
-  experimental(bool, FoldStableValues, false,                               \
-          "Private flag to control optimizations for stable variables")     \
+  diagnostic(bool, FoldStableValues, true,                                  \
+          "Optimize loads from stable fields (marked w/ @Stable)")          \
                                                                             \
   develop(bool, TraceInvokeDynamic, false,                                  \
           "trace internal invoke dynamic operations")                       \

hotspot/test/compiler/stable/TestStableBoolean.java

@@ -0,0 +1,627 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableBoolean
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableBoolean.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableBoolean
+ *           java/lang/invoke/TestStableBoolean$BooleanStable
+ *           java/lang/invoke/TestStableBoolean$StaticBooleanStable
+ *           java/lang/invoke/TestStableBoolean$VolatileBooleanStable
+ *           java/lang/invoke/TestStableBoolean$BooleanArrayDim1
+ *           java/lang/invoke/TestStableBoolean$BooleanArrayDim2
+ *           java/lang/invoke/TestStableBoolean$BooleanArrayDim3
+ *           java/lang/invoke/TestStableBoolean$BooleanArrayDim4
+ *           java/lang/invoke/TestStableBoolean$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableBoolean$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableBoolean$NestedStableField
+ *           java/lang/invoke/TestStableBoolean$NestedStableField$A
+ *           java/lang/invoke/TestStableBoolean$NestedStableField1
+ *           java/lang/invoke/TestStableBoolean$NestedStableField1$A
+ *           java/lang/invoke/TestStableBoolean$NestedStableField2
+ *           java/lang/invoke/TestStableBoolean$NestedStableField2$A
+ *           java/lang/invoke/TestStableBoolean$NestedStableField3
+ *           java/lang/invoke/TestStableBoolean$NestedStableField3$A
+ *           java/lang/invoke/TestStableBoolean$DefaultValue
+ *           java/lang/invoke/TestStableBoolean$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableBoolean
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableBoolean
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableBoolean
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableBoolean
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableBoolean {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(BooleanStable.class);
+        run(StaticBooleanStable.class);
+        run(VolatileBooleanStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(BooleanArrayDim1.class);
+        run(BooleanArrayDim2.class);
+        run(BooleanArrayDim3.class);
+        run(BooleanArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DefaultValue {
+        public @Stable boolean v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static boolean get() { return c.v; }
+        public static void test() throws Exception {
+                        boolean val1 = get();
+            c.v = true; boolean val2 = get();
+            assertEquals(val1, false);
+            assertEquals(val2, true);
+        }
+    }
+
+    /* ==================================================== */
+
+    static class BooleanStable {
+        public @Stable boolean v;
+
+        public static final BooleanStable c = new BooleanStable();
+        public static boolean get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = true; boolean val1 = get();
+            c.v = false; boolean val2 = get();
+            assertEquals(val1, true);
+            assertEquals(val2, (isStableEnabled ? true : false));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticBooleanStable {
+        public static @Stable boolean v;
+
+        public static final StaticBooleanStable c = new StaticBooleanStable();
+        public static boolean get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = true; boolean val1 = get();
+            c.v = false; boolean val2 = get();
+            assertEquals(val1, true);
+            assertEquals(val2, (isStableEnabled ? true : false));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileBooleanStable {
+        public @Stable volatile boolean v;
+
+        public static final VolatileBooleanStable c = new VolatileBooleanStable();
+        public static boolean get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = true; boolean val1 = get();
+            c.v = false; boolean val2 = get();
+            assertEquals(val1, true);
+            assertEquals(val2, (isStableEnabled ? true : false));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class BooleanArrayDim1 {
+        public @Stable boolean[] v;
+
+        public static final BooleanArrayDim1 c = new BooleanArrayDim1();
+        public static boolean get() { return c.v[0]; }
+        public static boolean get1() { return c.v[10]; }
+        public static boolean[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new boolean[1]; c.v[0] = true;  boolean val1 = get();
+                                      c.v[0] = false; boolean val2 = get();
+                assertEquals(val1, true);
+                assertEquals(val2, (isStableEnabled ? true : false));
+            }
+
+            {
+                c.v = new boolean[20]; c.v[10] = true;  boolean val1 = get1();
+                                       c.v[10] = false; boolean val2 = get1();
+                assertEquals(val1, true);
+                assertEquals(val2, (isStableEnabled ? true : false));
+            }
+
+            {
+                c.v = new boolean[1]; boolean[] val1 = get2();
+                c.v = new boolean[1]; boolean[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class BooleanArrayDim2 {
+        public @Stable boolean[][] v;
+
+        public static final BooleanArrayDim2 c = new BooleanArrayDim2();
+        public static boolean get() { return c.v[0][0]; }
+        public static boolean[] get1() { return c.v[0]; }
+        public static boolean[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new boolean[1][1]; c.v[0][0] = true;  boolean val1 = get();
+                                         c.v[0][0] = false; boolean val2 = get();
+                assertEquals(val1, true);
+                assertEquals(val2, (isStableEnabled ? true : false));
+
+                c.v = new boolean[1][1]; c.v[0][0] = false; boolean val3 = get();
+                assertEquals(val3, (isStableEnabled ? true : false));
+
+                c.v[0] = new boolean[1]; c.v[0][0] = false; boolean val4 = get();
+                assertEquals(val4, (isStableEnabled ? true : false));
+            }
+
+            {
+                c.v = new boolean[1][1]; boolean[] val1 = get1();
+                c.v[0] = new boolean[1]; boolean[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[1][1]; boolean[][] val1 = get2();
+                c.v = new boolean[1][1]; boolean[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class BooleanArrayDim3 {
+        public @Stable boolean[][][] v;
+
+        public static final BooleanArrayDim3 c = new BooleanArrayDim3();
+        public static boolean get() { return c.v[0][0][0]; }
+        public static boolean[] get1() { return c.v[0][0]; }
+        public static boolean[][] get2() { return c.v[0]; }
+        public static boolean[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new boolean[1][1][1]; c.v[0][0][0] = true;  boolean val1 = get();
+                                            c.v[0][0][0] = false; boolean val2 = get();
+                assertEquals(val1, true);
+                assertEquals(val2, (isStableEnabled ? true : false));
+
+                c.v = new boolean[1][1][1]; c.v[0][0][0] = false; boolean val3 = get();
+                assertEquals(val3, (isStableEnabled ? true : false));
+
+                c.v[0] = new boolean[1][1]; c.v[0][0][0] = false; boolean val4 = get();
+                assertEquals(val4, (isStableEnabled ? true : false));
+
+                c.v[0][0] = new boolean[1]; c.v[0][0][0] = false; boolean val5 = get();
+                assertEquals(val5, (isStableEnabled ? true : false));
+            }
+
+            {
+                c.v = new boolean[1][1][1]; boolean[] val1 = get1();
+                c.v[0][0] = new boolean[1]; boolean[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[1][1][1]; boolean[][] val1 = get2();
+                c.v[0] = new boolean[1][1]; boolean[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[1][1][1]; boolean[][][] val1 = get3();
+                c.v = new boolean[1][1][1]; boolean[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class BooleanArrayDim4 {
+        public @Stable boolean[][][][] v;
+
+        public static final BooleanArrayDim4 c = new BooleanArrayDim4();
+        public static boolean get() { return c.v[0][0][0][0]; }
+        public static boolean[] get1() { return c.v[0][0][0]; }
+        public static boolean[][] get2() { return c.v[0][0]; }
+        public static boolean[][][] get3() { return c.v[0]; }
+        public static boolean[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new boolean[1][1][1][1]; c.v[0][0][0][0] = true;  boolean val1 = get();
+                                               c.v[0][0][0][0] = false; boolean val2 = get();
+                assertEquals(val1, true);
+                assertEquals(val2, (isStableEnabled ? true : false));
+
+                c.v = new boolean[1][1][1][1]; c.v[0][0][0][0] = false; boolean val3 = get();
+                assertEquals(val3, (isStableEnabled ? true : false));
+
+                c.v[0] = new boolean[1][1][1]; c.v[0][0][0][0] = false; boolean val4 = get();
+                assertEquals(val4, (isStableEnabled ? true : false));
+
+                c.v[0][0] = new boolean[1][1]; c.v[0][0][0][0] = false; boolean val5 = get();
+                assertEquals(val5, (isStableEnabled ? true : false));
+
+                c.v[0][0][0] = new boolean[1]; c.v[0][0][0][0] = false; boolean val6 = get();
+                assertEquals(val6, (isStableEnabled ? true : false));
+            }
+
+            {
+                c.v = new boolean[1][1][1][1]; boolean[] val1 = get1();
+                c.v[0][0][0] = new boolean[1]; boolean[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[1][1][1][1]; boolean[][] val1 = get2();
+                c.v[0][0] = new boolean[1][1]; boolean[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[1][1][1][1]; boolean[][][] val1 = get3();
+                c.v[0] = new boolean[1][1][1]; boolean[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[1][1][1][1]; boolean[][][][] val1 = get4();
+                c.v = new boolean[1][1][1][1]; boolean[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static boolean get() { return ((boolean[])c.v)[0]; }
+        public static boolean[] get1() { return (boolean[])c.v; }
+        public static boolean[] get2() { return (boolean[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new boolean[1]; ((boolean[])c.v)[0] = true;  boolean val1 = get();
+                                      ((boolean[])c.v)[0] = false; boolean val2 = get();
+
+                assertEquals(val1, true);
+                assertEquals(val2, false);
+            }
+
+            {
+                c.v = new boolean[1]; boolean[] val1 = get1();
+                c.v = new boolean[1]; boolean[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static boolean get() { return ((boolean[][])c.v)[0][0]; }
+        public static boolean[] get1() { return (boolean[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new boolean[1][1]; ((boolean[][])c.v)[0][0] = true;  boolean val1 = get();
+                                         ((boolean[][])c.v)[0][0] = false; boolean val2 = get();
+
+                assertEquals(val1, true);
+                assertEquals(val2, false);
+            }
+
+            {
+                c.v = new boolean[1][1]; c.v[0] = new boolean[0]; boolean[] val1 = get1();
+                                         c.v[0] = new boolean[0]; boolean[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[0][0]; Object[] val1 = get2();
+                c.v = new boolean[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static boolean get() { return ((boolean[][][])c.v)[0][0][0]; }
+        public static boolean[] get1() { return (boolean[])(c.v[0][0]); }
+        public static boolean[][] get2() { return (boolean[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new boolean[1][1][1]; ((boolean[][][])c.v)[0][0][0] = true;  boolean val1 = get();
+                                            ((boolean[][][])c.v)[0][0][0] = false; boolean val2 = get();
+
+                assertEquals(val1, true);
+                assertEquals(val2, false);
+            }
+
+            {
+                c.v = new boolean[1][1][1]; c.v[0][0] = new boolean[0]; boolean[] val1 = get1();
+                                            c.v[0][0] = new boolean[0]; boolean[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[1][1][1]; c.v[0] = new boolean[0][0]; boolean[][] val1 = get2();
+                                            c.v[0] = new boolean[0][0]; boolean[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new boolean[0][0][0]; Object[][] val1 = get3();
+                c.v = new boolean[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable boolean a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static boolean get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = true;  A val1 = get();
+                               c.v.a = false; A val2 = get();
+
+                assertEquals(val1.a, false);
+                assertEquals(val2.a, false);
+            }
+
+            {
+                c.v = new A(); c.v.a = true;  boolean val1 = get1();
+                               c.v.a = false; boolean val2 = get1();
+                c.v = new A(); c.v.a = false; boolean val3 = get1();
+
+                assertEquals(val1, true);
+                assertEquals(val2, (isStableEnabled ? true : false));
+                assertEquals(val3, (isStableEnabled ? true : false));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable boolean a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static boolean get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A(); c.v.next.next  = c.v;
+                               c.v.a = true;  c.v.next.a = true;  A val1 = get();
+                               c.v.a = false; c.v.next.a = false; A val2 = get();
+
+                assertEquals(val1.a, false);
+                assertEquals(val2.a, false);
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = true;  boolean val1 = get1();
+                               c.v.a = false; boolean val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = false; boolean val3 = get1();
+
+                assertEquals(val1, true);
+                assertEquals(val2, (isStableEnabled ? true : false));
+                assertEquals(val3, (isStableEnabled ? true : false));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable boolean a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static boolean get() { return c.v.left.left.left.a; }
+        public static boolean get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = true;  boolean val1 = get(); boolean val2 = get1();
+                               c.v.a = false; boolean val3 = get(); boolean val4 = get1();
+
+                assertEquals(val1, true);
+                assertEquals(val3, (isStableEnabled ? true : false));
+
+                assertEquals(val2, true);
+                assertEquals(val4, false);
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable boolean a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static boolean get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static boolean get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = true;  boolean val1 = get(); boolean val2 = get1();
+                               elem.a = false; boolean val3 = get(); boolean val4 = get1();
+
+                assertEquals(val1, true);
+                assertEquals(val3, (isStableEnabled ? true : false));
+
+                assertEquals(val2, true);
+                assertEquals(val4, false);
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(boolean i, boolean j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}

hotspot/test/compiler/stable/TestStableByte.java

@@ -0,0 +1,632 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableByte
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableByte.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableByte
+ *           java/lang/invoke/TestStableByte$ByteStable
+ *           java/lang/invoke/TestStableByte$StaticByteStable
+ *           java/lang/invoke/TestStableByte$VolatileByteStable
+ *           java/lang/invoke/TestStableByte$ByteArrayDim1
+ *           java/lang/invoke/TestStableByte$ByteArrayDim2
+ *           java/lang/invoke/TestStableByte$ByteArrayDim3
+ *           java/lang/invoke/TestStableByte$ByteArrayDim4
+ *           java/lang/invoke/TestStableByte$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableByte$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableByte$NestedStableField
+ *           java/lang/invoke/TestStableByte$NestedStableField$A
+ *           java/lang/invoke/TestStableByte$NestedStableField1
+ *           java/lang/invoke/TestStableByte$NestedStableField1$A
+ *           java/lang/invoke/TestStableByte$NestedStableField2
+ *           java/lang/invoke/TestStableByte$NestedStableField2$A
+ *           java/lang/invoke/TestStableByte$NestedStableField3
+ *           java/lang/invoke/TestStableByte$NestedStableField3$A
+ *           java/lang/invoke/TestStableByte$DefaultValue
+ *           java/lang/invoke/TestStableByte$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableByte
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableByte
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableByte
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableByte
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableByte {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(ByteStable.class);
+        run(StaticByteStable.class);
+        run(VolatileByteStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(ByteArrayDim1.class);
+        run(ByteArrayDim2.class);
+        run(ByteArrayDim3.class);
+        run(ByteArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DefaultValue {
+        public @Stable byte v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static byte get() { return c.v; }
+        public static void test() throws Exception {
+                     byte val1 = get();
+            c.v = 1; byte val2 = get();
+            assertEquals(val1, 0);
+            assertEquals(val2, 1);
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ByteStable {
+        public @Stable byte v;
+
+        public static final ByteStable c = new ByteStable();
+        public static byte get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 5;   byte val1 = get();
+            c.v = 127; byte val2 = get();
+            assertEquals(val1, 5);
+            assertEquals(val2, (isStableEnabled ? 5 : 127));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticByteStable {
+        public static @Stable byte v;
+
+        public static final StaticByteStable c = new StaticByteStable();
+        public static byte get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 5;   byte val1 = get();
+            c.v = 127; byte val2 = get();
+            assertEquals(val1, 5);
+            assertEquals(val2, (isStableEnabled ? 5 : 127));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileByteStable {
+        public @Stable volatile byte v;
+
+        public static final VolatileByteStable c = new VolatileByteStable();
+        public static byte get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 5;   byte val1 = get();
+            c.v = 127; byte val2 = get();
+            assertEquals(val1, 5);
+            assertEquals(val2, (isStableEnabled ? 5 : 127));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class ByteArrayDim1 {
+        public @Stable byte[] v;
+
+        public static final ByteArrayDim1 c = new ByteArrayDim1();
+        public static byte get() { return c.v[0]; }
+        public static byte get1() { return c.v[10]; }
+        public static byte[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new byte[1]; c.v[0] = 1; byte val1 = get();
+                                   c.v[0] = 2; byte val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new byte[1]; c.v[0] = 3; byte val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+
+            {
+                c.v = new byte[20]; c.v[10] = 1; byte val1 = get1();
+                                    c.v[10] = 2; byte val2 = get1();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new byte[20]; c.v[10] = 3; byte val3 = get1();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+
+            {
+                c.v = new byte[1]; byte[] val1 = get2();
+                c.v = new byte[1]; byte[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ByteArrayDim2 {
+        public @Stable byte[][] v;
+
+        public static final ByteArrayDim2 c = new ByteArrayDim2();
+        public static byte get() { return c.v[0][0]; }
+        public static byte[] get1() { return c.v[0]; }
+        public static byte[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new byte[1][1]; c.v[0][0] = 1; byte val1 = get();
+                                      c.v[0][0] = 2; byte val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new byte[1][1]; c.v[0][0] = 3; byte val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new byte[1]; c.v[0][0] = 4; byte val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+            }
+
+            {
+                c.v = new byte[1][1]; byte[] val1 = get1();
+                c.v[0] = new byte[1]; byte[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[1][1]; byte[][] val1 = get2();
+                c.v = new byte[1][1]; byte[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ByteArrayDim3 {
+        public @Stable byte[][][] v;
+
+        public static final ByteArrayDim3 c = new ByteArrayDim3();
+        public static byte get() { return c.v[0][0][0]; }
+        public static byte[] get1() { return c.v[0][0]; }
+        public static byte[][] get2() { return c.v[0]; }
+        public static byte[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new byte[1][1][1]; c.v[0][0][0] = 1; byte val1 = get();
+                                         c.v[0][0][0] = 2; byte val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new byte[1][1][1]; c.v[0][0][0] = 3; byte val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new byte[1][1]; c.v[0][0][0] = 4; byte val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+
+                c.v[0][0] = new byte[1]; c.v[0][0][0] = 5; byte val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1 : 5));
+            }
+
+            {
+                c.v = new byte[1][1][1]; byte[] val1 = get1();
+                c.v[0][0] = new byte[1]; byte[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[1][1][1]; byte[][] val1 = get2();
+                c.v[0] = new byte[1][1]; byte[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[1][1][1]; byte[][][] val1 = get3();
+                c.v = new byte[1][1][1]; byte[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ByteArrayDim4 {
+        public @Stable byte[][][][] v;
+
+        public static final ByteArrayDim4 c = new ByteArrayDim4();
+        public static byte get() { return c.v[0][0][0][0]; }
+        public static byte[] get1() { return c.v[0][0][0]; }
+        public static byte[][] get2() { return c.v[0][0]; }
+        public static byte[][][] get3() { return c.v[0]; }
+        public static byte[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new byte[1][1][1][1]; c.v[0][0][0][0] = 1; byte val1 = get();
+                                            c.v[0][0][0][0] = 2; byte val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new byte[1][1][1][1]; c.v[0][0][0][0] = 3; byte val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new byte[1][1][1]; c.v[0][0][0][0] = 4; byte val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+
+                c.v[0][0] = new byte[1][1]; c.v[0][0][0][0] = 5; byte val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1 : 5));
+
+                c.v[0][0][0] = new byte[1]; c.v[0][0][0][0] = 6; byte val6 = get();
+                assertEquals(val6, (isStableEnabled ? 1 : 6));
+            }
+
+            {
+                c.v = new byte[1][1][1][1]; byte[] val1 = get1();
+                c.v[0][0][0] = new byte[1]; byte[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[1][1][1][1]; byte[][] val1 = get2();
+                c.v[0][0] = new byte[1][1]; byte[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[1][1][1][1]; byte[][][] val1 = get3();
+                c.v[0] = new byte[1][1][1]; byte[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[1][1][1][1]; byte[][][][] val1 = get4();
+                c.v = new byte[1][1][1][1]; byte[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static byte get() { return ((byte[])c.v)[0]; }
+        public static byte[] get1() { return (byte[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new byte[1]; ((byte[])c.v)[0] = 1; byte val1 = get();
+                                   ((byte[])c.v)[0] = 2; byte val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new byte[1]; byte[] val1 = get1();
+                c.v = new byte[1]; byte[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static byte get() { return ((byte[][])c.v)[0][0]; }
+        public static byte[] get1() { return (byte[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new byte[1][1]; ((byte[][])c.v)[0][0] = 1; byte val1 = get();
+                                      ((byte[][])c.v)[0][0] = 2; byte val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new byte[1][1]; c.v[0] = new byte[0]; byte[] val1 = get1();
+                                     c.v[0] = new byte[0]; byte[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[0][0]; Object[] val1 = get2();
+                c.v = new byte[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static byte get() { return ((byte[][][])c.v)[0][0][0]; }
+        public static byte[] get1() { return (byte[])(c.v[0][0]); }
+        public static byte[][] get2() { return (byte[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new byte[1][1][1]; ((byte[][][])c.v)[0][0][0] = 1;  byte val1 = get();
+                                         ((byte[][][])c.v)[0][0][0] = 2; byte val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new byte[1][1][1]; c.v[0][0] = new byte[0]; byte[] val1 = get1();
+                                         c.v[0][0] = new byte[0]; byte[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[1][1][1]; c.v[0] = new byte[0][0]; byte[][] val1 = get2();
+                                         c.v[0] = new byte[0][0]; byte[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new byte[0][0][0]; Object[][] val1 = get3();
+                c.v = new byte[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable byte a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static byte get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = 1; A val1 = get();
+                               c.v.a = 2; A val2 = get();
+
+                assertEquals(val1.a, 2);
+                assertEquals(val2.a, 2);
+            }
+
+            {
+                c.v = new A(); c.v.a = 1; byte val1 = get1();
+                               c.v.a = 2; byte val2 = get1();
+                c.v = new A(); c.v.a = 3; byte val3 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable byte a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static byte get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A();   c.v.next.next  = c.v;
+                               c.v.a = 1; c.v.next.a = 1; A val1 = get();
+                               c.v.a = 2; c.v.next.a = 2; A val2 = get();
+
+                assertEquals(val1.a, 2);
+                assertEquals(val2.a, 2);
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 1; byte val1 = get1();
+                               c.v.a = 2; byte val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 3; byte val3 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable byte a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static byte get() { return c.v.left.left.left.a; }
+        public static byte get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = 1; byte val1 = get(); byte val2 = get1();
+                               c.v.a = 2; byte val3 = get(); byte val4 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val3, (isStableEnabled ? 1 : 2));
+
+                assertEquals(val2, 1);
+                assertEquals(val4, 2);
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable byte a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static byte get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static byte get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = 1; byte val1 = get(); byte val2 = get1();
+                               elem.a = 2; byte val3 = get(); byte val4 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val3, (isStableEnabled ? 1 : 2));
+
+                assertEquals(val2, 1);
+                assertEquals(val4, 2);
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(int i, int j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}

hotspot/test/compiler/stable/TestStableChar.java

@@ -0,0 +1,631 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableChar
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableChar.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableChar
+ *           java/lang/invoke/TestStableChar$CharStable
+ *           java/lang/invoke/TestStableChar$StaticCharStable
+ *           java/lang/invoke/TestStableChar$VolatileCharStable
+ *           java/lang/invoke/TestStableChar$CharArrayDim1
+ *           java/lang/invoke/TestStableChar$CharArrayDim2
+ *           java/lang/invoke/TestStableChar$CharArrayDim3
+ *           java/lang/invoke/TestStableChar$CharArrayDim4
+ *           java/lang/invoke/TestStableChar$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableChar$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableChar$NestedStableField
+ *           java/lang/invoke/TestStableChar$NestedStableField$A
+ *           java/lang/invoke/TestStableChar$NestedStableField1
+ *           java/lang/invoke/TestStableChar$NestedStableField1$A
+ *           java/lang/invoke/TestStableChar$NestedStableField2
+ *           java/lang/invoke/TestStableChar$NestedStableField2$A
+ *           java/lang/invoke/TestStableChar$NestedStableField3
+ *           java/lang/invoke/TestStableChar$NestedStableField3$A
+ *           java/lang/invoke/TestStableChar$DefaultValue
+ *           java/lang/invoke/TestStableChar$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableChar
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableChar
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableChar
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableChar
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableChar {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(CharStable.class);
+        run(StaticCharStable.class);
+        run(VolatileCharStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(CharArrayDim1.class);
+        run(CharArrayDim2.class);
+        run(CharArrayDim3.class);
+        run(CharArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DefaultValue {
+        public @Stable char v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static char get() { return c.v; }
+        public static void test() throws Exception {
+                       char val1 = get();
+            c.v = 'a'; char val2 = get();
+            assertEquals(val1, 0);
+            assertEquals(val2, 'a');
+        }
+    }
+
+    /* ==================================================== */
+
+    static class CharStable {
+        public @Stable char v;
+
+        public static final CharStable c = new CharStable();
+        public static char get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 'a'; char val1 = get();
+            c.v = 'b'; char val2 = get();
+            assertEquals(val1, 'a');
+            assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticCharStable {
+        public @Stable char v;
+
+        public static final StaticCharStable c = new StaticCharStable();
+        public static char get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 'a'; char val1 = get();
+            c.v = 'b'; char val2 = get();
+            assertEquals(val1, 'a');
+            assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileCharStable {
+        public @Stable volatile char v;
+
+        public static final VolatileCharStable c = new VolatileCharStable();
+        public static char get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 'a'; char val1 = get();
+            c.v = 'b'; char val2 = get();
+            assertEquals(val1, 'a');
+            assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class CharArrayDim1 {
+        public @Stable char[] v;
+
+        public static final CharArrayDim1 c = new CharArrayDim1();
+        public static char get() { return c.v[0]; }
+        public static char get1() { return c.v[10]; }
+        public static char[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new char[1]; c.v[0] = 'a'; char val1 = get();
+                                   c.v[0] = 'b'; char val2 = get();
+                assertEquals(val1, 'a');
+                assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+
+                c.v = new char[1]; c.v[0] = 'c'; char val3 = get();
+                assertEquals(val3, (isStableEnabled ? 'a' : 'c'));
+            }
+
+            {
+                c.v = new char[20]; c.v[10] = 'a'; char val1 = get1();
+                                    c.v[10] = 'b'; char val2 = get1();
+                assertEquals(val1, 'a');
+                assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+
+                c.v = new char[20]; c.v[10] = 'c'; char val3 = get1();
+                assertEquals(val3, (isStableEnabled ? 'a' : 'c'));
+            }
+
+            {
+                c.v = new char[1]; char[] val1 = get2();
+                c.v = new char[1]; char[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class CharArrayDim2 {
+        public @Stable char[][] v;
+
+        public static final CharArrayDim2 c = new CharArrayDim2();
+        public static char get() { return c.v[0][0]; }
+        public static char[] get1() { return c.v[0]; }
+        public static char[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new char[1][1]; c.v[0][0] = 'a'; char val1 = get();
+                                      c.v[0][0] = 'b'; char val2 = get();
+                assertEquals(val1, 'a');
+                assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+
+                c.v = new char[1][1]; c.v[0][0] = 'c'; char val3 = get();
+                assertEquals(val3, (isStableEnabled ? 'a' : 'c'));
+
+                c.v[0] = new char[1]; c.v[0][0] = 'd'; char val4 = get();
+                assertEquals(val4, (isStableEnabled ? 'a' : 'd'));
+            }
+
+            {
+                c.v = new char[1][1]; char[] val1 = get1();
+                c.v[0] = new char[1]; char[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[1][1]; char[][] val1 = get2();
+                c.v = new char[1][1]; char[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class CharArrayDim3 {
+        public @Stable char[][][] v;
+
+        public static final CharArrayDim3 c = new CharArrayDim3();
+        public static char get() { return c.v[0][0][0]; }
+        public static char[] get1() { return c.v[0][0]; }
+        public static char[][] get2() { return c.v[0]; }
+        public static char[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new char[1][1][1]; c.v[0][0][0] = 'a'; char val1 = get();
+                                         c.v[0][0][0] = 'b'; char val2 = get();
+                assertEquals(val1, 'a');
+                assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+
+                c.v = new char[1][1][1]; c.v[0][0][0] = 'c'; char val3 = get();
+                assertEquals(val3, (isStableEnabled ? 'a' : 'c'));
+
+                c.v[0] = new char[1][1]; c.v[0][0][0] = 'd'; char val4 = get();
+                assertEquals(val4, (isStableEnabled ? 'a' : 'd'));
+
+                c.v[0][0] = new char[1]; c.v[0][0][0] = 'e'; char val5 = get();
+                assertEquals(val5, (isStableEnabled ? 'a' : 'e'));
+            }
+
+            {
+                c.v = new char[1][1][1]; char[] val1 = get1();
+                c.v[0][0] = new char[1]; char[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[1][1][1]; char[][] val1 = get2();
+                c.v[0] = new char[1][1]; char[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[1][1][1]; char[][][] val1 = get3();
+                c.v = new char[1][1][1]; char[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class CharArrayDim4 {
+        public @Stable char[][][][] v;
+
+        public static final CharArrayDim4 c = new CharArrayDim4();
+        public static char get() { return c.v[0][0][0][0]; }
+        public static char[] get1() { return c.v[0][0][0]; }
+        public static char[][] get2() { return c.v[0][0]; }
+        public static char[][][] get3() { return c.v[0]; }
+        public static char[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new char[1][1][1][1]; c.v[0][0][0][0] = 'a'; char val1 = get();
+                                            c.v[0][0][0][0] = 'b'; char val2 = get();
+                assertEquals(val1, 'a');
+                assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+
+                c.v = new char[1][1][1][1]; c.v[0][0][0][0] = 'c'; char val3 = get();
+                assertEquals(val3, (isStableEnabled ? 'a' : 'c'));
+
+                c.v[0] = new char[1][1][1]; c.v[0][0][0][0] = 'd'; char val4 = get();
+                assertEquals(val4, (isStableEnabled ? 'a' : 'd'));
+
+                c.v[0][0] = new char[1][1]; c.v[0][0][0][0] = 'e'; char val5 = get();
+                assertEquals(val5, (isStableEnabled ? 'a' : 'e'));
+
+                c.v[0][0][0] = new char[1]; c.v[0][0][0][0] = 'f'; char val6 = get();
+                assertEquals(val6, (isStableEnabled ? 'a' : 'f'));
+            }
+
+            {
+                c.v = new char[1][1][1][1]; char[] val1 = get1();
+                c.v[0][0][0] = new char[1]; char[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[1][1][1][1]; char[][] val1 = get2();
+                c.v[0][0] = new char[1][1]; char[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[1][1][1][1]; char[][][] val1 = get3();
+                c.v[0] = new char[1][1][1]; char[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[1][1][1][1]; char[][][][] val1 = get4();
+                c.v = new char[1][1][1][1]; char[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static char get() { return ((char[])c.v)[0]; }
+        public static char[] get1() { return (char[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new char[1]; ((char[])c.v)[0] = 'a'; char val1 = get();
+                                   ((char[])c.v)[0] = 'b'; char val2 = get();
+
+                assertEquals(val1, 'a');
+                assertEquals(val2, 'b');
+            }
+
+            {
+                c.v = new char[1]; char[] val1 = get1();
+                c.v = new char[1]; char[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static char get() { return ((char[][])c.v)[0][0]; }
+        public static char[] get1() { return (char[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new char[1][1]; ((char[][])c.v)[0][0] = 'a'; char val1 = get();
+                                      ((char[][])c.v)[0][0] = 'b'; char val2 = get();
+
+                assertEquals(val1, 'a');
+                assertEquals(val2, 'b');
+            }
+
+            {
+                c.v = new char[1][1]; c.v[0] = new char[0]; char[] val1 = get1();
+                                      c.v[0] = new char[0]; char[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[0][0]; Object[] val1 = get2();
+                c.v = new char[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static char get() { return ((char[][][])c.v)[0][0][0]; }
+        public static char[] get1() { return (char[])(c.v[0][0]); }
+        public static char[][] get2() { return (char[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new char[1][1][1]; ((char[][][])c.v)[0][0][0] = 'a';  char val1 = get();
+                                         ((char[][][])c.v)[0][0][0] = 'b'; char val2 = get();
+
+                assertEquals(val1, 'a');
+                assertEquals(val2, 'b');
+            }
+
+            {
+                c.v = new char[1][1][1]; c.v[0][0] = new char[0]; char[] val1 = get1();
+                                         c.v[0][0] = new char[0]; char[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[1][1][1]; c.v[0] = new char[0][0]; char[][] val1 = get2();
+                                         c.v[0] = new char[0][0]; char[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new char[0][0][0]; Object[][] val1 = get3();
+                c.v = new char[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable char a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static char get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = 'a'; A val1 = get();
+                               c.v.a = 'b'; A val2 = get();
+
+                assertEquals(val1.a, 'b');
+                assertEquals(val2.a, 'b');
+            }
+
+            {
+                c.v = new A(); c.v.a = 'a'; char val1 = get1();
+                               c.v.a = 'b'; char val2 = get1();
+                c.v = new A(); c.v.a = 'c'; char val3 = get1();
+
+                assertEquals(val1, 'a');
+                assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+                assertEquals(val3, (isStableEnabled ? 'a' : 'c'));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable char a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static char get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A(); c.v.next.next  = c.v;
+                               c.v.a = 'a'; c.v.next.a = 'a'; A val1 = get();
+                               c.v.a = 'b'; c.v.next.a = 'b'; A val2 = get();
+
+                assertEquals(val1.a, 'b');
+                assertEquals(val2.a, 'b');
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 'a'; char val1 = get1();
+                               c.v.a = 'b'; char val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 'c'; char val3 = get1();
+
+                assertEquals(val1, 'a');
+                assertEquals(val2, (isStableEnabled ? 'a' : 'b'));
+                assertEquals(val3, (isStableEnabled ? 'a' : 'c'));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable char a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static char get() { return c.v.left.left.left.a; }
+        public static char get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = 'a'; char val1 = get(); char val2 = get1();
+                               c.v.a = 'b'; char val3 = get(); char val4 = get1();
+
+                assertEquals(val1, 'a');
+                assertEquals(val3, (isStableEnabled ? 'a' : 'b'));
+
+                assertEquals(val2, 'a');
+                assertEquals(val4, 'b');
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable char a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static char get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static char get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = 'a'; char val1 = get(); char val2 = get1();
+                               elem.a = 'b'; char val3 = get(); char val4 = get1();
+
+                assertEquals(val1, 'a');
+                assertEquals(val3, (isStableEnabled ? 'a' : 'b'));
+
+                assertEquals(val2, 'a');
+                assertEquals(val4, 'b');
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(int i, int j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}

hotspot/test/compiler/stable/TestStableDouble.java

@@ -0,0 +1,632 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableDouble
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableDouble.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableDouble
+ *           java/lang/invoke/TestStableDouble$DoubleStable
+ *           java/lang/invoke/TestStableDouble$StaticDoubleStable
+ *           java/lang/invoke/TestStableDouble$VolatileDoubleStable
+ *           java/lang/invoke/TestStableDouble$DoubleArrayDim1
+ *           java/lang/invoke/TestStableDouble$DoubleArrayDim2
+ *           java/lang/invoke/TestStableDouble$DoubleArrayDim3
+ *           java/lang/invoke/TestStableDouble$DoubleArrayDim4
+ *           java/lang/invoke/TestStableDouble$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableDouble$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableDouble$NestedStableField
+ *           java/lang/invoke/TestStableDouble$NestedStableField$A
+ *           java/lang/invoke/TestStableDouble$NestedStableField1
+ *           java/lang/invoke/TestStableDouble$NestedStableField1$A
+ *           java/lang/invoke/TestStableDouble$NestedStableField2
+ *           java/lang/invoke/TestStableDouble$NestedStableField2$A
+ *           java/lang/invoke/TestStableDouble$NestedStableField3
+ *           java/lang/invoke/TestStableDouble$NestedStableField3$A
+ *           java/lang/invoke/TestStableDouble$DefaultValue
+ *           java/lang/invoke/TestStableDouble$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableDouble
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableDouble
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableDouble
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableDouble
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableDouble {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(DoubleStable.class);
+        run(StaticDoubleStable.class);
+        run(VolatileDoubleStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(DoubleArrayDim1.class);
+        run(DoubleArrayDim2.class);
+        run(DoubleArrayDim3.class);
+        run(DoubleArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DefaultValue {
+        public @Stable double v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static double get() { return c.v; }
+        public static void test() throws Exception {
+                       double val1 = get();
+            c.v = 1.0; double val2 = get();
+            assertEquals(val1, 0);
+            assertEquals(val2, 1.0);
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DoubleStable {
+        public @Stable double v;
+
+        public static final DoubleStable c = new DoubleStable();
+        public static double get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1.0; double val1 = get();
+            c.v = Double.MAX_VALUE; double val2 = get();
+            assertEquals(val1, 1.0);
+            assertEquals(val2, (isStableEnabled ? 1.0 : Double.MAX_VALUE));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticDoubleStable {
+        public static @Stable double v;
+
+        public static final StaticDoubleStable c = new StaticDoubleStable();
+        public static double get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1.0; double val1 = get();
+            c.v = Double.MAX_VALUE; double val2 = get();
+            assertEquals(val1, 1.0);
+            assertEquals(val2, (isStableEnabled ? 1.0 : Double.MAX_VALUE));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileDoubleStable {
+        public @Stable double v;
+
+        public static final VolatileDoubleStable c = new VolatileDoubleStable();
+        public static double get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1.0; double val1 = get();
+            c.v = Double.MAX_VALUE; double val2 = get();
+            assertEquals(val1, 1.0);
+            assertEquals(val2, (isStableEnabled ? 1.0 : Double.MAX_VALUE));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class DoubleArrayDim1 {
+        public @Stable double[] v;
+
+        public static final DoubleArrayDim1 c = new DoubleArrayDim1();
+        public static double get() { return c.v[0]; }
+        public static double get1() { return c.v[10]; }
+        public static double[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new double[1]; c.v[0] = 1.0; double val1 = get();
+                                     c.v[0] = 2.0; double val2 = get();
+                assertEquals(val1, 1.0);
+                assertEquals(val2, (isStableEnabled ? 1.0 : 2.0));
+
+                c.v = new double[1]; c.v[0] = 3.0; double val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1.0 : 3.0));
+            }
+
+            {
+                c.v = new double[20]; c.v[10] = 1.0; double val1 = get1();
+                                      c.v[10] = 2.0; double val2 = get1();
+                assertEquals(val1, 1.0);
+                assertEquals(val2, (isStableEnabled ? 1.0 : 2.0));
+
+                c.v = new double[20]; c.v[10] = 3.0; double val3 = get1();
+                assertEquals(val3, (isStableEnabled ? 1.0 : 3.0));
+            }
+
+            {
+                c.v = new double[1]; double[] val1 = get2();
+                c.v = new double[1]; double[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DoubleArrayDim2 {
+        public @Stable double[][] v;
+
+        public static final DoubleArrayDim2 c = new DoubleArrayDim2();
+        public static double get() { return c.v[0][0]; }
+        public static double[] get1() { return c.v[0]; }
+        public static double[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new double[1][1]; c.v[0][0] = 1.0; double val1 = get();
+                                        c.v[0][0] = 2.0; double val2 = get();
+                assertEquals(val1, 1.0);
+                assertEquals(val2, (isStableEnabled ? 1.0 : 2.0));
+
+                c.v = new double[1][1]; c.v[0][0] = 3.0; double val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1.0 : 3.0));
+
+                c.v[0] = new double[1]; c.v[0][0] = 4.0; double val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1.0 : 4.0));
+            }
+
+            {
+                c.v = new double[1][1]; double[] val1 = get1();
+                c.v[0] = new double[1]; double[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[1][1]; double[][] val1 = get2();
+                c.v = new double[1][1]; double[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DoubleArrayDim3 {
+        public @Stable double[][][] v;
+
+        public static final DoubleArrayDim3 c = new DoubleArrayDim3();
+        public static double get() { return c.v[0][0][0]; }
+        public static double[] get1() { return c.v[0][0]; }
+        public static double[][] get2() { return c.v[0]; }
+        public static double[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new double[1][1][1]; c.v[0][0][0] = 1.0; double val1 = get();
+                                           c.v[0][0][0] = 2.0; double val2 = get();
+                assertEquals(val1, 1.0);
+                assertEquals(val2, (isStableEnabled ? 1.0 : 2.0));
+
+                c.v = new double[1][1][1]; c.v[0][0][0] = 3.0; double val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1.0 : 3.0));
+
+                c.v[0] = new double[1][1]; c.v[0][0][0] = 4.0; double val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1.0 : 4.0));
+
+                c.v[0][0] = new double[1]; c.v[0][0][0] = 5.0; double val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1.0 : 5.0));
+            }
+
+            {
+                c.v = new double[1][1][1]; double[] val1 = get1();
+                c.v[0][0] = new double[1]; double[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[1][1][1]; double[][] val1 = get2();
+                c.v[0] = new double[1][1]; double[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[1][1][1]; double[][][] val1 = get3();
+                c.v = new double[1][1][1]; double[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DoubleArrayDim4 {
+        public @Stable double[][][][] v;
+
+        public static final DoubleArrayDim4 c = new DoubleArrayDim4();
+        public static double get() { return c.v[0][0][0][0]; }
+        public static double[] get1() { return c.v[0][0][0]; }
+        public static double[][] get2() { return c.v[0][0]; }
+        public static double[][][] get3() { return c.v[0]; }
+        public static double[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new double[1][1][1][1]; c.v[0][0][0][0] = 1.0; double val1 = get();
+                                              c.v[0][0][0][0] = 2.0; double val2 = get();
+                assertEquals(val1, 1.0);
+                assertEquals(val2, (isStableEnabled ? 1.0 : 2.0));
+
+                c.v = new double[1][1][1][1]; c.v[0][0][0][0] = 3.0; double val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1.0 : 3.0));
+
+                c.v[0] = new double[1][1][1]; c.v[0][0][0][0] = 4.0; double val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1.0 : 4.0));
+
+                c.v[0][0] = new double[1][1]; c.v[0][0][0][0] = 5.0; double val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1.0 : 5.0));
+
+                c.v[0][0][0] = new double[1]; c.v[0][0][0][0] = 6.0; double val6 = get();
+                assertEquals(val6, (isStableEnabled ? 1.0 : 6.0));
+            }
+
+            {
+                c.v = new double[1][1][1][1]; double[] val1 = get1();
+                c.v[0][0][0] = new double[1]; double[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[1][1][1][1]; double[][] val1 = get2();
+                c.v[0][0] = new double[1][1]; double[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[1][1][1][1]; double[][][] val1 = get3();
+                c.v[0] = new double[1][1][1]; double[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[1][1][1][1]; double[][][][] val1 = get4();
+                c.v = new double[1][1][1][1]; double[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static double get() { return ((double[])c.v)[0]; }
+        public static double[] get1() { return (double[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new double[1]; ((double[])c.v)[0] = 1.0; double val1 = get();
+                                     ((double[])c.v)[0] = 2.0; double val2 = get();
+
+                assertEquals(val1, 1.0);
+                assertEquals(val2, 2.0);
+            }
+
+            {
+                c.v = new double[1]; double[] val1 = get1();
+                c.v = new double[1]; double[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static double get() { return ((double[][])c.v)[0][0]; }
+        public static double[] get1() { return (double[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new double[1][1]; ((double[][])c.v)[0][0] = 1.0; double val1 = get();
+                                        ((double[][])c.v)[0][0] = 2.0; double val2 = get();
+
+                assertEquals(val1, 1.0);
+                assertEquals(val2, 2.0);
+            }
+
+            {
+                c.v = new double[1][1]; c.v[0] = new double[0]; double[] val1 = get1();
+                                        c.v[0] = new double[0]; double[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[0][0]; Object[] val1 = get2();
+                c.v = new double[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static double get() { return ((double[][][])c.v)[0][0][0]; }
+        public static double[] get1() { return (double[])(c.v[0][0]); }
+        public static double[][] get2() { return (double[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new double[1][1][1]; ((double[][][])c.v)[0][0][0] = 1.0; double val1 = get();
+                                           ((double[][][])c.v)[0][0][0] = 2.0; double val2 = get();
+
+                assertEquals(val1, 1.0);
+                assertEquals(val2, 2.0);
+            }
+
+            {
+                c.v = new double[1][1][1]; c.v[0][0] = new double[0]; double[] val1 = get1();
+                                           c.v[0][0] = new double[0]; double[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[1][1][1]; c.v[0] = new double[0][0]; double[][] val1 = get2();
+                                           c.v[0] = new double[0][0]; double[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new double[0][0][0]; Object[][] val1 = get3();
+                c.v = new double[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable double a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static double get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = 1.0; A val1 = get();
+                               c.v.a = 2.0; A val2 = get();
+
+                assertEquals(val1.a, 2.0);
+                assertEquals(val2.a, 2.0);
+            }
+
+            {
+                c.v = new A(); c.v.a = 1.0; double val1 = get1();
+                               c.v.a = 2.0; double val2 = get1();
+                c.v = new A(); c.v.a = 3.0; double val3 = get1();
+
+                assertEquals(val1, 1.0);
+                assertEquals(val2, (isStableEnabled ? 1.0 : 2.0));
+                assertEquals(val3, (isStableEnabled ? 1.0 : 3.0));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable double a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static double get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A();   c.v.next.next  = c.v;
+                               c.v.a = 1.0; c.v.next.a = 1.0; A val1 = get();
+                               c.v.a = 2.0; c.v.next.a = 2.0; A val2 = get();
+
+                assertEquals(val1.a, 2.0);
+                assertEquals(val2.a, 2.0);
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 1.0; double val1 = get1();
+                               c.v.a = 2.0; double val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 3.0; double val3 = get1();
+
+                assertEquals(val1, 1.0);
+                assertEquals(val2, (isStableEnabled ? 1.0 : 2.0));
+                assertEquals(val3, (isStableEnabled ? 1.0 : 3.0));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable double a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static double get() { return c.v.left.left.left.a; }
+        public static double get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = 1.0; double val1 = get(); double val2 = get1();
+                               c.v.a = 2.0; double val3 = get(); double val4 = get1();
+
+                assertEquals(val1, 1.0);
+                assertEquals(val3, (isStableEnabled ? 1.0 : 2.0));
+
+                assertEquals(val2, 1.0);
+                assertEquals(val4, 2.0);
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable double a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static double get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static double get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = 1.0; double val1 = get(); double val2 = get1();
+                               elem.a = 2.0; double val3 = get(); double val4 = get1();
+
+                assertEquals(val1, 1.0);
+                assertEquals(val3, (isStableEnabled ? 1.0 : 2.0));
+
+                assertEquals(val2, 1.0);
+                assertEquals(val4, 2.0);
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(double i, double j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}

hotspot/test/compiler/stable/TestStableFloat.java

@@ -0,0 +1,632 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableFloat
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableFloat.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableFloat
+ *           java/lang/invoke/TestStableFloat$FloatStable
+ *           java/lang/invoke/TestStableFloat$StaticFloatStable
+ *           java/lang/invoke/TestStableFloat$VolatileFloatStable
+ *           java/lang/invoke/TestStableFloat$FloatArrayDim1
+ *           java/lang/invoke/TestStableFloat$FloatArrayDim2
+ *           java/lang/invoke/TestStableFloat$FloatArrayDim3
+ *           java/lang/invoke/TestStableFloat$FloatArrayDim4
+ *           java/lang/invoke/TestStableFloat$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableFloat$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableFloat$NestedStableField
+ *           java/lang/invoke/TestStableFloat$NestedStableField$A
+ *           java/lang/invoke/TestStableFloat$NestedStableField1
+ *           java/lang/invoke/TestStableFloat$NestedStableField1$A
+ *           java/lang/invoke/TestStableFloat$NestedStableField2
+ *           java/lang/invoke/TestStableFloat$NestedStableField2$A
+ *           java/lang/invoke/TestStableFloat$NestedStableField3
+ *           java/lang/invoke/TestStableFloat$NestedStableField3$A
+ *           java/lang/invoke/TestStableFloat$DefaultValue
+ *           java/lang/invoke/TestStableFloat$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableFloat
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableFloat
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableFloat
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableFloat
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableFloat {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(FloatStable.class);
+        run(StaticFloatStable.class);
+        run(VolatileFloatStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(FloatArrayDim1.class);
+        run(FloatArrayDim2.class);
+        run(FloatArrayDim3.class);
+        run(FloatArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DefaultValue {
+        public @Stable float v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static float get() { return c.v; }
+        public static void test() throws Exception {
+                        float val1 = get();
+            c.v = 1.0F; float val2 = get();
+            assertEquals(val1, 0F);
+            assertEquals(val2, 1.0F);
+        }
+    }
+
+    /* ==================================================== */
+
+    static class FloatStable {
+        public @Stable float v;
+
+        public static final FloatStable c = new FloatStable();
+        public static float get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1.0F; float val1 = get();
+            c.v = 2.0F; float val2 = get();
+            assertEquals(val1, 1.0F);
+            assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticFloatStable {
+        public static @Stable float v;
+
+        public static final StaticFloatStable c = new StaticFloatStable();
+        public static float get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1.0F; float val1 = get();
+            c.v = 2.0F; float val2 = get();
+            assertEquals(val1, 1.0F);
+            assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileFloatStable {
+        public @Stable volatile float v;
+
+        public static final VolatileFloatStable c = new VolatileFloatStable();
+        public static float get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1.0F; float val1 = get();
+            c.v = 2.0F; float val2 = get();
+            assertEquals(val1, 1.0F);
+            assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class FloatArrayDim1 {
+        public @Stable float[] v;
+
+        public static final FloatArrayDim1 c = new FloatArrayDim1();
+        public static float get() { return c.v[0]; }
+        public static float get1() { return c.v[10]; }
+        public static float[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new float[1]; c.v[0] = 1.0F; float val1 = get();
+                                    c.v[0] = 2.0F; float val2 = get();
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+
+                c.v = new float[1]; c.v[0] = 3.0F; float val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1.0F : 3.0F));
+            }
+
+            {
+                c.v = new float[20]; c.v[10] = 1.0F; float val1 = get1();
+                                     c.v[10] = 2.0F; float val2 = get1();
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+
+                c.v = new float[20]; c.v[10] = 3.0F; float val3 = get1();
+                assertEquals(val3, (isStableEnabled ? 1.0F : 3.0F));
+            }
+
+            {
+                c.v = new float[1]; float[] val1 = get2();
+                c.v = new float[1]; float[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class FloatArrayDim2 {
+        public @Stable float[][] v;
+
+        public static final FloatArrayDim2 c = new FloatArrayDim2();
+        public static float get() { return c.v[0][0]; }
+        public static float[] get1() { return c.v[0]; }
+        public static float[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new float[1][1]; c.v[0][0] = 1.0F; float val1 = get();
+                                       c.v[0][0] = 2.0F; float val2 = get();
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+
+                c.v = new float[1][1]; c.v[0][0] = 3.0F; float val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1.0F : 3.0F));
+
+                c.v[0] = new float[1]; c.v[0][0] = 4.0F; float val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1.0F : 4.0F));
+            }
+
+            {
+                c.v = new float[1][1]; float[] val1 = get1();
+                c.v[0] = new float[1]; float[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[1][1]; float[][] val1 = get2();
+                c.v = new float[1][1]; float[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class FloatArrayDim3 {
+        public @Stable float[][][] v;
+
+        public static final FloatArrayDim3 c = new FloatArrayDim3();
+        public static float get() { return c.v[0][0][0]; }
+        public static float[] get1() { return c.v[0][0]; }
+        public static float[][] get2() { return c.v[0]; }
+        public static float[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new float[1][1][1]; c.v[0][0][0] = 1.0F; float val1 = get();
+                                          c.v[0][0][0] = 2.0F; float val2 = get();
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+
+                c.v = new float[1][1][1]; c.v[0][0][0] = 3.0F; float val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1.0F : 3.0F));
+
+                c.v[0] = new float[1][1]; c.v[0][0][0] = 4.0F; float val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1.0F : 4.0F));
+
+                c.v[0][0] = new float[1]; c.v[0][0][0] = 5.0F; float val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1.0F : 5.0F));
+            }
+
+            {
+                c.v = new float[1][1][1]; float[] val1 = get1();
+                c.v[0][0] = new float[1]; float[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[1][1][1]; float[][] val1 = get2();
+                c.v[0] = new float[1][1]; float[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[1][1][1]; float[][][] val1 = get3();
+                c.v = new float[1][1][1]; float[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class FloatArrayDim4 {
+        public @Stable float[][][][] v;
+
+        public static final FloatArrayDim4 c = new FloatArrayDim4();
+        public static float get() { return c.v[0][0][0][0]; }
+        public static float[] get1() { return c.v[0][0][0]; }
+        public static float[][] get2() { return c.v[0][0]; }
+        public static float[][][] get3() { return c.v[0]; }
+        public static float[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new float[1][1][1][1]; c.v[0][0][0][0] = 1.0F; float val1 = get();
+                                             c.v[0][0][0][0] = 2.0F; float val2 = get();
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+
+                c.v = new float[1][1][1][1]; c.v[0][0][0][0] = 3.0F; float val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1.0F : 3.0F));
+
+                c.v[0] = new float[1][1][1]; c.v[0][0][0][0] = 4.0F; float val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1.0F : 4.0F));
+
+                c.v[0][0] = new float[1][1]; c.v[0][0][0][0] = 5.0F; float val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1.0F : 5.0F));
+
+                c.v[0][0][0] = new float[1]; c.v[0][0][0][0] = 6.0F; float val6 = get();
+                assertEquals(val6, (isStableEnabled ? 1.0F : 6.0F));
+            }
+
+            {
+                c.v = new float[1][1][1][1]; float[] val1 = get1();
+                c.v[0][0][0] = new float[1]; float[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[1][1][1][1]; float[][] val1 = get2();
+                c.v[0][0] = new float[1][1]; float[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[1][1][1][1]; float[][][] val1 = get3();
+                c.v[0] = new float[1][1][1]; float[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[1][1][1][1]; float[][][][] val1 = get4();
+                c.v = new float[1][1][1][1]; float[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static float get() { return ((float[])c.v)[0]; }
+        public static float[] get1() { return (float[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new float[1]; ((float[])c.v)[0] = 1.0F; float val1 = get();
+                                    ((float[])c.v)[0] = 2.0F; float val2 = get();
+
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, 2.0F);
+            }
+
+            {
+                c.v = new float[1]; float[] val1 = get1();
+                c.v = new float[1]; float[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static float get() { return ((float[][])c.v)[0][0]; }
+        public static float[] get1() { return (float[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new float[1][1]; ((float[][])c.v)[0][0] = 1.0F; float val1 = get();
+                                       ((float[][])c.v)[0][0] = 2.0F; float val2 = get();
+
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, 2.0F);
+            }
+
+            {
+                c.v = new float[1][1]; c.v[0] = new float[0]; float[] val1 = get1();
+                                       c.v[0] = new float[0]; float[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[0][0]; Object[] val1 = get2();
+                c.v = new float[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static float get() { return ((float[][][])c.v)[0][0][0]; }
+        public static float[] get1() { return (float[])(c.v[0][0]); }
+        public static float[][] get2() { return (float[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new float[1][1][1]; ((float[][][])c.v)[0][0][0] = 1.0F; float val1 = get();
+                                          ((float[][][])c.v)[0][0][0] = 2.0F; float val2 = get();
+
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, 2.0F);
+            }
+
+            {
+                c.v = new float[1][1][1]; c.v[0][0] = new float[0]; float[] val1 = get1();
+                                          c.v[0][0] = new float[0]; float[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[1][1][1]; c.v[0] = new float[0][0]; float[][] val1 = get2();
+                                          c.v[0] = new float[0][0]; float[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new float[0][0][0]; Object[][] val1 = get3();
+                c.v = new float[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable float a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static float get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = 1.0F; A val1 = get();
+                               c.v.a = 2.0F; A val2 = get();
+
+                assertEquals(val1.a, 2.0F);
+                assertEquals(val2.a, 2.0F);
+            }
+
+            {
+                c.v = new A(); c.v.a = 1.0F; float val1 = get1();
+                               c.v.a = 2.0F; float val2 = get1();
+                c.v = new A(); c.v.a = 3.0F; float val3 = get1();
+
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+                assertEquals(val3, (isStableEnabled ? 1.0F : 3.0F));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable float a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static float get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A();   c.v.next.next  = c.v;
+                               c.v.a = 1.0F; c.v.next.a = 1.0F; A val1 = get();
+                               c.v.a = 2.0F; c.v.next.a = 2.0F; A val2 = get();
+
+                assertEquals(val1.a, 2.0F);
+                assertEquals(val2.a, 2.0F);
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 1.0F; float val1 = get1();
+                               c.v.a = 2.0F; float val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 3.0F; float val3 = get1();
+
+                assertEquals(val1, 1.0F);
+                assertEquals(val2, (isStableEnabled ? 1.0F : 2.0F));
+                assertEquals(val3, (isStableEnabled ? 1.0F : 3.0F));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable float a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static float get() { return c.v.left.left.left.a; }
+        public static float get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = 1.0F; float val1 = get(); float val2 = get1();
+                               c.v.a = 2.0F; float val3 = get(); float val4 = get1();
+
+                assertEquals(val1, 1.0F);
+                assertEquals(val3, (isStableEnabled ? 1.0F : 2.0F));
+
+                assertEquals(val2, 1.0F);
+                assertEquals(val4, 2.0F);
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable float a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static float get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static float get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = 1.0F; float val1 = get(); float val2 = get1();
+                               elem.a = 2.0F; float val3 = get(); float val4 = get1();
+
+                assertEquals(val1, 1.0F);
+                assertEquals(val3, (isStableEnabled ? 1.0F : 2.0F));
+
+                assertEquals(val2, 1.0F);
+                assertEquals(val4, 2.0F);
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(float i, float j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}

hotspot/test/compiler/stable/TestStableInt.java

@@ -0,0 +1,632 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableInt
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableInt.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableInt
+ *           java/lang/invoke/TestStableInt$IntStable
+ *           java/lang/invoke/TestStableInt$StaticIntStable
+ *           java/lang/invoke/TestStableInt$VolatileIntStable
+ *           java/lang/invoke/TestStableInt$IntArrayDim1
+ *           java/lang/invoke/TestStableInt$IntArrayDim2
+ *           java/lang/invoke/TestStableInt$IntArrayDim3
+ *           java/lang/invoke/TestStableInt$IntArrayDim4
+ *           java/lang/invoke/TestStableInt$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableInt$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableInt$NestedStableField
+ *           java/lang/invoke/TestStableInt$NestedStableField$A
+ *           java/lang/invoke/TestStableInt$NestedStableField1
+ *           java/lang/invoke/TestStableInt$NestedStableField1$A
+ *           java/lang/invoke/TestStableInt$NestedStableField2
+ *           java/lang/invoke/TestStableInt$NestedStableField2$A
+ *           java/lang/invoke/TestStableInt$NestedStableField3
+ *           java/lang/invoke/TestStableInt$NestedStableField3$A
+ *           java/lang/invoke/TestStableInt$DefaultValue
+ *           java/lang/invoke/TestStableInt$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableInt
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableInt
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableInt
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableInt
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableInt {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(IntStable.class);
+        run(StaticIntStable.class);
+        run(VolatileIntStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(IntArrayDim1.class);
+        run(IntArrayDim2.class);
+        run(IntArrayDim3.class);
+        run(IntArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DefaultValue {
+        public @Stable int v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static int get() { return c.v; }
+        public static void test() throws Exception {
+                        int val1 = get();
+            c.v = 1; int val2 = get();
+            assertEquals(val1, 0);
+            assertEquals(val2, 1);
+        }
+    }
+
+    /* ==================================================== */
+
+    static class IntStable {
+        public @Stable int v;
+
+        public static final IntStable c = new IntStable();
+        public static int get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1; int val1 = get();
+            c.v = 2; int val2 = get();
+            assertEquals(val1, 1);
+            assertEquals(val2, (isStableEnabled ? 1 : 2));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticIntStable {
+        public static @Stable int v;
+
+        public static final StaticIntStable c = new StaticIntStable();
+        public static int get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1; int val1 = get();
+            c.v = 2; int val2 = get();
+            assertEquals(val1, 1);
+            assertEquals(val2, (isStableEnabled ? 1 : 2));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileIntStable {
+        public @Stable volatile int v;
+
+        public static final VolatileIntStable c = new VolatileIntStable();
+        public static int get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1; int val1 = get();
+            c.v = 2; int val2 = get();
+            assertEquals(val1, 1);
+            assertEquals(val2, (isStableEnabled ? 1 : 2));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class IntArrayDim1 {
+        public @Stable int[] v;
+
+        public static final IntArrayDim1 c = new IntArrayDim1();
+        public static int get() { return c.v[0]; }
+        public static int get1() { return c.v[10]; }
+        public static int[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new int[1]; c.v[0] = 1; int val1 = get();
+                                  c.v[0] = 2; int val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new int[1]; c.v[0] = 3; int val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+
+            {
+                c.v = new int[20]; c.v[10] = 1; int val1 = get1();
+                                   c.v[10] = 2; int val2 = get1();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new int[20]; c.v[10] = 3; int val3 = get1();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+
+            {
+                c.v = new int[1]; int[] val1 = get2();
+                c.v = new int[1]; int[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class IntArrayDim2 {
+        public @Stable int[][] v;
+
+        public static final IntArrayDim2 c = new IntArrayDim2();
+        public static int get() { return c.v[0][0]; }
+        public static int[] get1() { return c.v[0]; }
+        public static int[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new int[1][1]; c.v[0][0] = 1; int val1 = get();
+                                     c.v[0][0] = 2; int val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new int[1][1]; c.v[0][0] = 3; int val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new int[1]; c.v[0][0] = 4; int val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+            }
+
+            {
+                c.v = new int[1][1]; int[] val1 = get1();
+                c.v[0] = new int[1]; int[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[1][1]; int[][] val1 = get2();
+                c.v = new int[1][1]; int[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class IntArrayDim3 {
+        public @Stable int[][][] v;
+
+        public static final IntArrayDim3 c = new IntArrayDim3();
+        public static int get() { return c.v[0][0][0]; }
+        public static int[] get1() { return c.v[0][0]; }
+        public static int[][] get2() { return c.v[0]; }
+        public static int[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new int[1][1][1]; c.v[0][0][0] = 1; int val1 = get();
+                                        c.v[0][0][0] = 2; int val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new int[1][1][1]; c.v[0][0][0] = 3; int val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new int[1][1]; c.v[0][0][0] = 4; int val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+
+                c.v[0][0] = new int[1]; c.v[0][0][0] = 5; int val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1 : 5));
+            }
+
+            {
+                c.v = new int[1][1][1]; int[] val1 = get1();
+                c.v[0][0] = new int[1]; int[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[1][1][1]; int[][] val1 = get2();
+                c.v[0] = new int[1][1]; int[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[1][1][1]; int[][][] val1 = get3();
+                c.v = new int[1][1][1]; int[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class IntArrayDim4 {
+        public @Stable int[][][][] v;
+
+        public static final IntArrayDim4 c = new IntArrayDim4();
+        public static int get() { return c.v[0][0][0][0]; }
+        public static int[] get1() { return c.v[0][0][0]; }
+        public static int[][] get2() { return c.v[0][0]; }
+        public static int[][][] get3() { return c.v[0]; }
+        public static int[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new int[1][1][1][1]; c.v[0][0][0][0] = 1; int val1 = get();
+                                           c.v[0][0][0][0] = 2; int val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new int[1][1][1][1]; c.v[0][0][0][0] = 3; int val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new int[1][1][1]; c.v[0][0][0][0] = 4; int val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+
+                c.v[0][0] = new int[1][1]; c.v[0][0][0][0] = 5; int val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1 : 5));
+
+                c.v[0][0][0] = new int[1]; c.v[0][0][0][0] = 6; int val6 = get();
+                assertEquals(val6, (isStableEnabled ? 1 : 6));
+            }
+
+            {
+                c.v = new int[1][1][1][1]; int[] val1 = get1();
+                c.v[0][0][0] = new int[1]; int[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[1][1][1][1]; int[][] val1 = get2();
+                c.v[0][0] = new int[1][1]; int[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[1][1][1][1]; int[][][] val1 = get3();
+                c.v[0] = new int[1][1][1]; int[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[1][1][1][1]; int[][][][] val1 = get4();
+                c.v = new int[1][1][1][1]; int[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static int get() { return ((int[])c.v)[0]; }
+        public static int[] get1() { return (int[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new int[1]; ((int[])c.v)[0] = 1; int val1 = get();
+                                  ((int[])c.v)[0] = 2; int val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new int[1]; int[] val1 = get1();
+                c.v = new int[1]; int[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static int get() { return ((int[][])c.v)[0][0]; }
+        public static int[] get1() { return (int[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new int[1][1]; ((int[][])c.v)[0][0] = 1; int val1 = get();
+                                     ((int[][])c.v)[0][0] = 2; int val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new int[1][1]; c.v[0] = new int[0]; int[] val1 = get1();
+                                     c.v[0] = new int[0]; int[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[0][0]; Object[] val1 = get2();
+                c.v = new int[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static int get() { return ((int[][][])c.v)[0][0][0]; }
+        public static int[] get1() { return (int[])(c.v[0][0]); }
+        public static int[][] get2() { return (int[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new int[1][1][1]; ((int[][][])c.v)[0][0][0] = 1; int val1 = get();
+                                        ((int[][][])c.v)[0][0][0] = 2; int val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new int[1][1][1]; c.v[0][0] = new int[0]; int[] val1 = get1();
+                                        c.v[0][0] = new int[0]; int[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[1][1][1]; c.v[0] = new int[0][0]; int[][] val1 = get2();
+                                        c.v[0] = new int[0][0]; int[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new int[0][0][0]; Object[][] val1 = get3();
+                c.v = new int[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable int a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static int get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = 1; A val1 = get();
+                               c.v.a = 2; A val2 = get();
+
+                assertEquals(val1.a, 2);
+                assertEquals(val2.a, 2);
+            }
+
+            {
+                c.v = new A(); c.v.a = 1; int val1 = get1();
+                               c.v.a = 2; int val2 = get1();
+                c.v = new A(); c.v.a = 3; int val3 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable int a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static int get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A();   c.v.next.next  = c.v;
+                               c.v.a = 1; c.v.next.a = 1; A val1 = get();
+                               c.v.a = 2; c.v.next.a = 2; A val2 = get();
+
+                assertEquals(val1.a, 2);
+                assertEquals(val2.a, 2);
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 1; int val1 = get1();
+                               c.v.a = 2; int val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 3; int val3 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable int a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static int get() { return c.v.left.left.left.a; }
+        public static int get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = 1; int val1 = get(); int val2 = get1();
+                               c.v.a = 2; int val3 = get(); int val4 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val3, (isStableEnabled ? 1 : 2));
+
+                assertEquals(val2, 1);
+                assertEquals(val4, 2);
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable int a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static int get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static int get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = 1; int val1 = get(); int val2 = get1();
+                               elem.a = 2; int val3 = get(); int val4 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val3, (isStableEnabled ? 1 : 2));
+
+                assertEquals(val2, 1);
+                assertEquals(val4, 2);
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(int i, int j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}

hotspot/test/compiler/stable/TestStableLong.java

@@ -0,0 +1,632 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableLong
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableLong.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableLong
+ *           java/lang/invoke/TestStableLong$LongStable
+ *           java/lang/invoke/TestStableLong$StaticLongStable
+ *           java/lang/invoke/TestStableLong$VolatileLongStable
+ *           java/lang/invoke/TestStableLong$LongArrayDim1
+ *           java/lang/invoke/TestStableLong$LongArrayDim2
+ *           java/lang/invoke/TestStableLong$LongArrayDim3
+ *           java/lang/invoke/TestStableLong$LongArrayDim4
+ *           java/lang/invoke/TestStableLong$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableLong$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableLong$NestedStableField
+ *           java/lang/invoke/TestStableLong$NestedStableField$A
+ *           java/lang/invoke/TestStableLong$NestedStableField1
+ *           java/lang/invoke/TestStableLong$NestedStableField1$A
+ *           java/lang/invoke/TestStableLong$NestedStableField2
+ *           java/lang/invoke/TestStableLong$NestedStableField2$A
+ *           java/lang/invoke/TestStableLong$NestedStableField3
+ *           java/lang/invoke/TestStableLong$NestedStableField3$A
+ *           java/lang/invoke/TestStableLong$DefaultValue
+ *           java/lang/invoke/TestStableLong$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableLong
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableLong
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableLong
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableLong
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableLong {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(LongStable.class);
+        run(StaticLongStable.class);
+        run(VolatileLongStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(LongArrayDim1.class);
+        run(LongArrayDim2.class);
+        run(LongArrayDim3.class);
+        run(LongArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DefaultValue {
+        public @Stable long v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static long get() { return c.v; }
+        public static void test() throws Exception {
+                      long val1 = get();
+            c.v = 1L; long val2 = get();
+            assertEquals(val1, 0);
+            assertEquals(val2, 1L);
+        }
+    }
+
+    /* ==================================================== */
+
+    static class LongStable {
+        public @Stable long v;
+
+        public static final LongStable c = new LongStable();
+        public static long get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 5;              long val1 = get();
+            c.v = Long.MAX_VALUE; long val2 = get();
+            assertEquals(val1, 5);
+            assertEquals(val2, (isStableEnabled ? 5 : Long.MAX_VALUE));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticLongStable {
+        public static @Stable long v;
+
+        public static final StaticLongStable c = new StaticLongStable();
+        public static long get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 5;              long val1 = get();
+            c.v = Long.MAX_VALUE; long val2 = get();
+            assertEquals(val1, 5);
+            assertEquals(val2, (isStableEnabled ? 5 : Long.MAX_VALUE));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileLongStable {
+        public @Stable volatile long v;
+
+        public static final VolatileLongStable c = new VolatileLongStable();
+        public static long get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 5;              long val1 = get();
+            c.v = Long.MAX_VALUE; long val2 = get();
+            assertEquals(val1, 5);
+            assertEquals(val2, (isStableEnabled ? 5 : Long.MAX_VALUE));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class LongArrayDim1 {
+        public @Stable long[] v;
+
+        public static final LongArrayDim1 c = new LongArrayDim1();
+        public static long get() { return c.v[0]; }
+        public static long get1() { return c.v[10]; }
+        public static long[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new long[1]; c.v[0] = 1; long val1 = get();
+                                   c.v[0] = 2; long val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new long[1]; c.v[0] = 3; long val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+
+            {
+                c.v = new long[20]; c.v[10] = 1; long val1 = get1();
+                                    c.v[10] = 2; long val2 = get1();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new long[20]; c.v[10] = 3; long val3 = get1();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+
+            {
+                c.v = new long[1]; long[] val1 = get2();
+                c.v = new long[1]; long[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class LongArrayDim2 {
+        public @Stable long[][] v;
+
+        public static final LongArrayDim2 c = new LongArrayDim2();
+        public static long get() { return c.v[0][0]; }
+        public static long[] get1() { return c.v[0]; }
+        public static long[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new long[1][1]; c.v[0][0] = 1; long val1 = get();
+                                      c.v[0][0] = 2; long val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new long[1][1]; c.v[0][0] = 3; long val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new long[1]; c.v[0][0] = 4; long val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+            }
+
+            {
+                c.v = new long[1][1]; long[] val1 = get1();
+                c.v[0] = new long[1]; long[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[1][1]; long[][] val1 = get2();
+                c.v = new long[1][1]; long[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class LongArrayDim3 {
+        public @Stable long[][][] v;
+
+        public static final LongArrayDim3 c = new LongArrayDim3();
+        public static long get() { return c.v[0][0][0]; }
+        public static long[] get1() { return c.v[0][0]; }
+        public static long[][] get2() { return c.v[0]; }
+        public static long[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new long[1][1][1]; c.v[0][0][0] = 1; long val1 = get();
+                                         c.v[0][0][0] = 2; long val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new long[1][1][1]; c.v[0][0][0] = 3; long val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new long[1][1]; c.v[0][0][0] = 4; long val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+
+                c.v[0][0] = new long[1]; c.v[0][0][0] = 5; long val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1 : 5));
+            }
+
+            {
+                c.v = new long[1][1][1]; long[] val1 = get1();
+                c.v[0][0] = new long[1]; long[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[1][1][1]; long[][] val1 = get2();
+                c.v[0] = new long[1][1]; long[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[1][1][1]; long[][][] val1 = get3();
+                c.v = new long[1][1][1]; long[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class LongArrayDim4 {
+        public @Stable long[][][][] v;
+
+        public static final LongArrayDim4 c = new LongArrayDim4();
+        public static long get() { return c.v[0][0][0][0]; }
+        public static long[] get1() { return c.v[0][0][0]; }
+        public static long[][] get2() { return c.v[0][0]; }
+        public static long[][][] get3() { return c.v[0]; }
+        public static long[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new long[1][1][1][1]; c.v[0][0][0][0] = 1; long val1 = get();
+                                            c.v[0][0][0][0] = 2; long val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new long[1][1][1][1]; c.v[0][0][0][0] = 3; long val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new long[1][1][1]; c.v[0][0][0][0] = 4; long val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+
+                c.v[0][0] = new long[1][1]; c.v[0][0][0][0] = 5; long val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1 : 5));
+
+                c.v[0][0][0] = new long[1]; c.v[0][0][0][0] = 6; long val6 = get();
+                assertEquals(val6, (isStableEnabled ? 1 : 6));
+            }
+
+            {
+                c.v = new long[1][1][1][1]; long[] val1 = get1();
+                c.v[0][0][0] = new long[1]; long[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[1][1][1][1]; long[][] val1 = get2();
+                c.v[0][0] = new long[1][1]; long[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[1][1][1][1]; long[][][] val1 = get3();
+                c.v[0] = new long[1][1][1]; long[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[1][1][1][1]; long[][][][] val1 = get4();
+                c.v = new long[1][1][1][1]; long[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static long get() { return ((long[])c.v)[0]; }
+        public static long[] get1() { return (long[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new long[1]; ((long[])c.v)[0] = 1; long val1 = get();
+                                   ((long[])c.v)[0] = 2; long val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new long[1]; long[] val1 = get1();
+                c.v = new long[1]; long[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static long get() { return ((long[][])c.v)[0][0]; }
+        public static long[] get1() { return (long[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new long[1][1]; ((long[][])c.v)[0][0] = 1; long val1 = get();
+                                      ((long[][])c.v)[0][0] = 2; long val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new long[1][1]; c.v[0] = new long[0]; long[] val1 = get1();
+                                     c.v[0] = new long[0]; long[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[0][0]; Object[] val1 = get2();
+                c.v = new long[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static long get() { return ((long[][][])c.v)[0][0][0]; }
+        public static long[] get1() { return (long[])(c.v[0][0]); }
+        public static long[][] get2() { return (long[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new long[1][1][1]; ((long[][][])c.v)[0][0][0] = 1L; long val1 = get();
+                                         ((long[][][])c.v)[0][0][0] = 2L; long val2 = get();
+
+                assertEquals(val1, 1L);
+                assertEquals(val2, 2L);
+            }
+
+            {
+                c.v = new long[1][1][1]; c.v[0][0] = new long[0]; long[] val1 = get1();
+                                         c.v[0][0] = new long[0]; long[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[1][1][1]; c.v[0] = new long[0][0]; long[][] val1 = get2();
+                                         c.v[0] = new long[0][0]; long[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new long[0][0][0]; Object[][] val1 = get3();
+                c.v = new long[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable long a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static long get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = 1; A val1 = get();
+                               c.v.a = 2; A val2 = get();
+
+                assertEquals(val1.a, 2);
+                assertEquals(val2.a, 2);
+            }
+
+            {
+                c.v = new A(); c.v.a = 1; long val1 = get1();
+                               c.v.a = 2; long val2 = get1();
+                c.v = new A(); c.v.a = 3; long val3 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable long a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static long get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A();   c.v.next.next  = c.v;
+                               c.v.a = 1; c.v.next.a = 1; A val1 = get();
+                               c.v.a = 2; c.v.next.a = 2; A val2 = get();
+
+                assertEquals(val1.a, 2);
+                assertEquals(val2.a, 2);
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 1; long val1 = get1();
+                               c.v.a = 2; long val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 3; long val3 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable long a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static long get() { return c.v.left.left.left.a; }
+        public static long get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = 1; long val1 = get(); long val2 = get1();
+                               c.v.a = 2; long val3 = get(); long val4 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val3, (isStableEnabled ? 1 : 2));
+
+                assertEquals(val2, 1);
+                assertEquals(val4, 2);
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable long a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static long get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static long get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = 1; long val1 = get(); long val2 = get1();
+                               elem.a = 2; long val3 = get(); long val4 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val3, (isStableEnabled ? 1 : 2));
+
+                assertEquals(val2, 1);
+                assertEquals(val4, 2);
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(long i, long j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}

hotspot/test/compiler/stable/TestStableObject.java

@@ -0,0 +1,635 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableObject
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableObject.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableObject
+ *           java/lang/invoke/TestStableObject$ObjectStable
+ *           java/lang/invoke/TestStableObject$StaticObjectStable
+ *           java/lang/invoke/TestStableObject$VolatileObjectStable
+ *           java/lang/invoke/TestStableObject$ObjectArrayDim1
+ *           java/lang/invoke/TestStableObject$ObjectArrayDim2
+ *           java/lang/invoke/TestStableObject$ObjectArrayDim3
+ *           java/lang/invoke/TestStableObject$ObjectArrayDim4
+ *           java/lang/invoke/TestStableObject$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableObject$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableObject$NestedStableField
+ *           java/lang/invoke/TestStableObject$NestedStableField$A
+ *           java/lang/invoke/TestStableObject$NestedStableField1
+ *           java/lang/invoke/TestStableObject$NestedStableField1$A
+ *           java/lang/invoke/TestStableObject$NestedStableField2
+ *           java/lang/invoke/TestStableObject$NestedStableField2$A
+ *           java/lang/invoke/TestStableObject$NestedStableField3
+ *           java/lang/invoke/TestStableObject$NestedStableField3$A
+ *           java/lang/invoke/TestStableObject$Values
+ *           java/lang/invoke/TestStableObject$DefaultValue
+ *           java/lang/invoke/TestStableObject$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableObject
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableObject
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableObject
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableObject
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableObject {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(ObjectStable.class);
+        run(StaticObjectStable.class);
+        run(VolatileObjectStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(ObjectArrayDim1.class);
+        run(ObjectArrayDim2.class);
+        run(ObjectArrayDim3.class);
+        run(ObjectArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    enum Values {A, B, C, D, E, F}
+
+    static class DefaultValue {
+        public @Stable Object v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static Object get() { return c.v; }
+        public static void test() throws Exception {
+                            Object val1 = get();
+            c.v = Values.A; Object val2 = get();
+            assertEquals(val1, null);
+            assertEquals(val2, Values.A);
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectStable {
+        public @Stable Values v;
+
+        public static final ObjectStable c = new ObjectStable ();
+        public static Values get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = Values.A; Values val1 = get();
+            c.v = Values.B; Values val2 = get();
+            assertEquals(val1, Values.A);
+            assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticObjectStable {
+        public static @Stable Values v;
+
+        public static final ObjectStable c = new ObjectStable ();
+        public static Values get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = Values.A; Values val1 = get();
+            c.v = Values.B; Values val2 = get();
+            assertEquals(val1, Values.A);
+            assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileObjectStable {
+        public @Stable volatile Values v;
+
+        public static final VolatileObjectStable c = new VolatileObjectStable ();
+        public static Values get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = Values.A; Values val1 = get();
+            c.v = Values.B; Values val2 = get();
+            assertEquals(val1, Values.A);
+            assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class ObjectArrayDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayDim1 c = new ObjectArrayDim1();
+        public static Object get() { return c.v[0]; }
+        public static Object get1() { return c.v[10]; }
+        public static Object[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new Object[1]; c.v[0] = Values.A; Object val1 = get();
+                                     c.v[0] = Values.B; Object val2 = get();
+                assertEquals(val1, Values.A);
+                assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+
+                c.v = new Object[1]; c.v[0] = Values.C; Object val3 = get();
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.C));
+            }
+
+            {
+                c.v = new Object[20]; c.v[10] = Values.A; Object val1 = get1();
+                                      c.v[10] = Values.B; Object val2 = get1();
+                assertEquals(val1, Values.A);
+                assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+
+                c.v = new Object[20]; c.v[10] = Values.C; Object val3 = get1();
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.C));
+            }
+
+            {
+                c.v = new Object[1]; Object[] val1 = get2();
+                c.v = new Object[1]; Object[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayDim2 c = new ObjectArrayDim2();
+        public static Object get() { return c.v[0][0]; }
+        public static Object[] get1() { return c.v[0]; }
+        public static Object[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new Object[1][1]; c.v[0][0] = Values.A; Object val1 = get();
+                                        c.v[0][0] = Values.B; Object val2 = get();
+                assertEquals(val1, Values.A);
+                assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+
+                c.v = new Object[1][1]; c.v[0][0] = Values.C; Object val3 = get();
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.C));
+
+                c.v[0] = new Object[1]; c.v[0][0] = Values.D; Object val4 = get();
+                assertEquals(val4, (isStableEnabled ? Values.A : Values.D));
+            }
+
+            {
+                c.v = new Object[1][1]; Object[] val1 = get1();
+                c.v[0] = new Object[1]; Object[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[1][1]; Object[][] val1 = get2();
+                c.v = new Object[1][1]; Object[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayDim3 {
+        public @Stable Object[][][] v;
+
+        public static final ObjectArrayDim3 c = new ObjectArrayDim3();
+        public static Object get() { return c.v[0][0][0]; }
+        public static Object[] get1() { return c.v[0][0]; }
+        public static Object[][] get2() { return c.v[0]; }
+        public static Object[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new Object[1][1][1]; c.v[0][0][0] = Values.A; Object val1 = get();
+                                           c.v[0][0][0] = Values.B; Object val2 = get();
+                assertEquals(val1, Values.A);
+                assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+
+                c.v = new Object[1][1][1]; c.v[0][0][0] = Values.C; Object val3 = get();
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.C));
+
+                c.v[0] = new Object[1][1]; c.v[0][0][0] = Values.D; Object val4 = get();
+                assertEquals(val4, (isStableEnabled ? Values.A : Values.D));
+
+                c.v[0][0] = new Object[1]; c.v[0][0][0] = Values.E; Object val5 = get();
+                assertEquals(val5, (isStableEnabled ? Values.A : Values.E));
+            }
+
+            {
+                c.v = new Object[1][1][1]; Object[] val1 = get1();
+                c.v[0][0] = new Object[1]; Object[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[1][1][1]; Object[][] val1 = get2();
+                c.v[0] = new Object[1][1]; Object[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[1][1][1]; Object[][][] val1 = get3();
+                c.v = new Object[1][1][1]; Object[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayDim4 {
+        public @Stable Object[][][][] v;
+
+        public static final ObjectArrayDim4 c = new ObjectArrayDim4();
+        public static Object get() { return c.v[0][0][0][0]; }
+        public static Object[] get1() { return c.v[0][0][0]; }
+        public static Object[][] get2() { return c.v[0][0]; }
+        public static Object[][][] get3() { return c.v[0]; }
+        public static Object[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new Object[1][1][1][1]; c.v[0][0][0][0] = Values.A; Object val1 = get();
+                                              c.v[0][0][0][0] = Values.B; Object val2 = get();
+                assertEquals(val1, Values.A);
+                assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+
+                c.v = new Object[1][1][1][1]; c.v[0][0][0][0] = Values.C; Object val3 = get();
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.C));
+
+                c.v[0] = new Object[1][1][1]; c.v[0][0][0][0] = Values.D; Object val4 = get();
+                assertEquals(val4, (isStableEnabled ? Values.A : Values.D));
+
+                c.v[0][0] = new Object[1][1]; c.v[0][0][0][0] = Values.E; Object val5 = get();
+                assertEquals(val5, (isStableEnabled ? Values.A : Values.E));
+
+                c.v[0][0][0] = new Object[1]; c.v[0][0][0][0] = Values.F; Object val6 = get();
+                assertEquals(val6, (isStableEnabled ? Values.A : Values.F));
+            }
+
+            {
+                c.v = new Object[1][1][1][1]; Object[] val1 = get1();
+                c.v[0][0][0] = new Object[1]; Object[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[1][1][1][1]; Object[][] val1 = get2();
+                c.v[0][0] = new Object[1][1]; Object[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[1][1][1][1]; Object[][][] val1 = get3();
+                c.v[0] = new Object[1][1][1]; Object[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[1][1][1][1]; Object[][][][] val1 = get4();
+                c.v = new Object[1][1][1][1]; Object[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static Object get() { return ((Object[])c.v)[0]; }
+        public static Object[] get1() { return (Object[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new Object[1]; ((Object[])c.v)[0] = Values.A; Object val1 = get();
+                                     ((Object[])c.v)[0] = Values.B; Object val2 = get();
+
+                assertEquals(val1, Values.A);
+                assertEquals(val2, Values.B);
+            }
+
+            {
+                c.v = new Object[1]; Object[] val1 = get1();
+                c.v = new Object[1]; Object[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static Object get() { return ((Object[][])c.v)[0][0]; }
+        public static Object[] get1() { return (Object[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new Object[1][1]; ((Object[][])c.v)[0][0] = Values.A; Object val1 = get();
+                                        ((Object[][])c.v)[0][0] = Values.B; Object val2 = get();
+
+                assertEquals(val1, Values.A);
+                assertEquals(val2, Values.B);
+            }
+
+            {
+                c.v = new Object[1][1]; c.v[0] = new Object[0]; Object[] val1 = get1();
+                                     c.v[0] = new Object[0]; Object[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[0][0]; Object[] val1 = get2();
+                c.v = new Object[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static Object get() { return ((Object[][][])c.v)[0][0][0]; }
+        public static Object[] get1() { return (Object[])(c.v[0][0]); }
+        public static Object[][] get2() { return (Object[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new Object[1][1][1]; ((Object[][][])c.v)[0][0][0] = Values.A; Object val1 = get();
+                                           ((Object[][][])c.v)[0][0][0] = Values.B; Object val2 = get();
+
+                assertEquals(val1, Values.A);
+                assertEquals(val2, Values.B);
+            }
+
+            {
+                c.v = new Object[1][1][1]; c.v[0][0] = new Object[0]; Object[] val1 = get1();
+                                           c.v[0][0] = new Object[0]; Object[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[1][1][1]; c.v[0] = new Object[0][0]; Object[][] val1 = get2();
+                                           c.v[0] = new Object[0][0]; Object[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new Object[0][0][0]; Object[][] val1 = get3();
+                c.v = new Object[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable Object a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static Object get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = Values.A; A val1 = get();
+                               c.v.a = Values.B; A val2 = get();
+
+                assertEquals(val1.a, Values.B);
+                assertEquals(val2.a, Values.B);
+            }
+
+            {
+                c.v = new A(); c.v.a = Values.A; Object val1 = get1();
+                               c.v.a = Values.B; Object val2 = get1();
+                c.v = new A(); c.v.a = Values.C; Object val3 = get1();
+
+                assertEquals(val1, Values.A);
+                assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.C));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable Object a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static Object get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A();   c.v.next.next  = c.v;
+                               c.v.a = Values.A; c.v.next.a = Values.A; A val1 = get();
+                               c.v.a = Values.B; c.v.next.a = Values.B; A val2 = get();
+
+                assertEquals(val1.a, Values.B);
+                assertEquals(val2.a, Values.B);
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = Values.A; Object val1 = get1();
+                               c.v.a = Values.B; Object val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = Values.C; Object val3 = get1();
+
+                assertEquals(val1, Values.A);
+                assertEquals(val2, (isStableEnabled ? Values.A : Values.B));
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.C));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable Object a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static Object get() { return c.v.left.left.left.a; }
+        public static Object get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = Values.A; Object val1 = get(); Object val2 = get1();
+                               c.v.a = Values.B; Object val3 = get(); Object val4 = get1();
+
+                assertEquals(val1, Values.A);
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.B));
+
+                assertEquals(val2, Values.A);
+                assertEquals(val4, Values.B);
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable Object a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static Object get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static Object get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = Values.A; Object val1 = get(); Object val2 = get1();
+                               elem.a = Values.B; Object val3 = get(); Object val4 = get1();
+
+                assertEquals(val1, Values.A);
+                assertEquals(val3, (isStableEnabled ? Values.A : Values.B));
+
+                assertEquals(val2, Values.A);
+                assertEquals(val4, Values.B);
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(Object i, Object j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}

hotspot/test/compiler/stable/TestStableShort.java

@@ -0,0 +1,632 @@
+/*
+ * Copyright (c) 2014, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 TestStableShort
+ * @summary tests on stable fields and arrays
+ * @library /testlibrary
+ * @compile -XDignore.symbol.file TestStableShort.java
+ * @run main ClassFileInstaller
+ *           java/lang/invoke/TestStableShort
+ *           java/lang/invoke/TestStableShort$ShortStable
+ *           java/lang/invoke/TestStableShort$StaticShortStable
+ *           java/lang/invoke/TestStableShort$VolatileShortStable
+ *           java/lang/invoke/TestStableShort$ShortArrayDim1
+ *           java/lang/invoke/TestStableShort$ShortArrayDim2
+ *           java/lang/invoke/TestStableShort$ShortArrayDim3
+ *           java/lang/invoke/TestStableShort$ShortArrayDim4
+ *           java/lang/invoke/TestStableShort$ObjectArrayLowerDim0
+ *           java/lang/invoke/TestStableShort$ObjectArrayLowerDim1
+ *           java/lang/invoke/TestStableShort$NestedStableField
+ *           java/lang/invoke/TestStableShort$NestedStableField$A
+ *           java/lang/invoke/TestStableShort$NestedStableField1
+ *           java/lang/invoke/TestStableShort$NestedStableField1$A
+ *           java/lang/invoke/TestStableShort$NestedStableField2
+ *           java/lang/invoke/TestStableShort$NestedStableField2$A
+ *           java/lang/invoke/TestStableShort$NestedStableField3
+ *           java/lang/invoke/TestStableShort$NestedStableField3$A
+ *           java/lang/invoke/TestStableShort$DefaultValue
+ *           java/lang/invoke/TestStableShort$ObjectArrayLowerDim2
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableShort
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:+FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableShort
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:+UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableShort
+ *
+ * @run main/othervm -Xbootclasspath/a:. -XX:+IgnoreUnrecognizedVMOptions
+ *                   -XX:+UnlockDiagnosticVMOptions -XX:-FoldStableValues -XX:-UseCompressedOop
+ *                   -server -XX:-TieredCompilation -Xcomp
+ *                   -XX:CompileOnly=::get,::get1,::get2,::get3,::get4
+ *                   java.lang.invoke.TestStableShort
+ */
+package java.lang.invoke;
+
+import com.sun.management.HotSpotDiagnosticMXBean;
+import com.sun.management.VMOption;
+import sun.management.ManagementFactoryHelper;
+import java.lang.reflect.InvocationTargetException;
+
+public class TestStableShort {
+    public static void main(String[] args) throws Exception {
+        System.out.println("@Stable enabled: "+isStableEnabled);
+        System.out.println();
+
+        run(DefaultValue.class);
+        run(ShortStable.class);
+        run(StaticShortStable.class);
+        run(VolatileShortStable.class);
+
+        // @Stable arrays: Dim 1-4
+        run(ShortArrayDim1.class);
+        run(ShortArrayDim2.class);
+        run(ShortArrayDim3.class);
+        run(ShortArrayDim4.class);
+
+        // @Stable Object field: dynamic arrays
+        run(ObjectArrayLowerDim0.class);
+        run(ObjectArrayLowerDim1.class);
+        run(ObjectArrayLowerDim2.class);
+
+        // Nested @Stable fields
+        run(NestedStableField.class);
+        run(NestedStableField1.class);
+        run(NestedStableField2.class);
+        run(NestedStableField3.class);
+
+        if (failed) {
+            throw new Error("TEST FAILED");
+        }
+    }
+
+    /* ==================================================== */
+
+    static class DefaultValue {
+        public @Stable short v;
+
+        public static final DefaultValue c = new DefaultValue();
+        public static short get() { return c.v; }
+        public static void test() throws Exception {
+                     short val1 = get();
+            c.v = 1; short val2 = get();
+            assertEquals(val1, 0);
+            assertEquals(val2, 1);
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ShortStable {
+        public @Stable short v;
+
+        public static final ShortStable c = new ShortStable();
+        public static short get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1;     short val1 = get();
+            c.v = 32767; short val2 = get();
+            assertEquals(val1, 1);
+            assertEquals(val2, (isStableEnabled ? 1 : 32767));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class StaticShortStable {
+        public static @Stable short v;
+
+        public static final StaticShortStable c = new StaticShortStable();
+        public static short get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1;     short val1 = get();
+            c.v = 32767; short val2 = get();
+            assertEquals(val1, 1);
+            assertEquals(val2, (isStableEnabled ? 1 : 32767));
+        }
+    }
+
+    /* ==================================================== */
+
+    static class VolatileShortStable {
+        public @Stable volatile short v;
+
+        public static final VolatileShortStable c = new VolatileShortStable();
+        public static short get() { return c.v; }
+        public static void test() throws Exception {
+            c.v = 1;     short val1 = get();
+            c.v = 32767; short val2 = get();
+            assertEquals(val1, 1);
+            assertEquals(val2, (isStableEnabled ? 1 : 32767));
+        }
+    }
+
+    /* ==================================================== */
+    // @Stable array == field && all components are stable
+
+    static class ShortArrayDim1 {
+        public @Stable short[] v;
+
+        public static final ShortArrayDim1 c = new ShortArrayDim1();
+        public static short get() { return c.v[0]; }
+        public static short get1() { return c.v[10]; }
+        public static short[] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new short[1]; c.v[0] = 1; short val1 = get();
+                                    c.v[0] = 2; short val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new short[1]; c.v[0] = 3; short val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+
+            {
+                c.v = new short[20]; c.v[10] = 1; short val1 = get1();
+                                     c.v[10] = 2; short val2 = get1();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new short[20]; c.v[10] = 3; short val3 = get1();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+
+            {
+                c.v = new short[1]; short[] val1 = get2();
+                c.v = new short[1]; short[] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ShortArrayDim2 {
+        public @Stable short[][] v;
+
+        public static final ShortArrayDim2 c = new ShortArrayDim2();
+        public static short get() { return c.v[0][0]; }
+        public static short[] get1() { return c.v[0]; }
+        public static short[][] get2() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new short[1][1]; c.v[0][0] = 1; short val1 = get();
+                                       c.v[0][0] = 2; short val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new short[1][1]; c.v[0][0] = 3; short val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new short[1]; c.v[0][0] = 4; short val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+            }
+
+            {
+                c.v = new short[1][1]; short[] val1 = get1();
+                c.v[0] = new short[1]; short[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[1][1]; short[][] val1 = get2();
+                c.v = new short[1][1]; short[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ShortArrayDim3 {
+        public @Stable short[][][] v;
+
+        public static final ShortArrayDim3 c = new ShortArrayDim3();
+        public static short get() { return c.v[0][0][0]; }
+        public static short[] get1() { return c.v[0][0]; }
+        public static short[][] get2() { return c.v[0]; }
+        public static short[][][] get3() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new short[1][1][1]; c.v[0][0][0] = 1; short val1 = get();
+                                          c.v[0][0][0] = 2; short val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new short[1][1][1]; c.v[0][0][0] = 3; short val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new short[1][1]; c.v[0][0][0] = 4; short val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+
+                c.v[0][0] = new short[1]; c.v[0][0][0] = 5; short val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1 : 5));
+            }
+
+            {
+                c.v = new short[1][1][1]; short[] val1 = get1();
+                c.v[0][0] = new short[1]; short[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[1][1][1]; short[][] val1 = get2();
+                c.v[0] = new short[1][1]; short[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[1][1][1]; short[][][] val1 = get3();
+                c.v = new short[1][1][1]; short[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ShortArrayDim4 {
+        public @Stable short[][][][] v;
+
+        public static final ShortArrayDim4 c = new ShortArrayDim4();
+        public static short get() { return c.v[0][0][0][0]; }
+        public static short[] get1() { return c.v[0][0][0]; }
+        public static short[][] get2() { return c.v[0][0]; }
+        public static short[][][] get3() { return c.v[0]; }
+        public static short[][][][] get4() { return c.v; }
+        public static void test() throws Exception {
+            {
+                c.v = new short[1][1][1][1]; c.v[0][0][0][0] = 1; short val1 = get();
+                                             c.v[0][0][0][0] = 2; short val2 = get();
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+
+                c.v = new short[1][1][1][1]; c.v[0][0][0][0] = 3; short val3 = get();
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+
+                c.v[0] = new short[1][1][1]; c.v[0][0][0][0] = 4; short val4 = get();
+                assertEquals(val4, (isStableEnabled ? 1 : 4));
+
+                c.v[0][0] = new short[1][1]; c.v[0][0][0][0] = 5; short val5 = get();
+                assertEquals(val5, (isStableEnabled ? 1 : 5));
+
+                c.v[0][0][0] = new short[1]; c.v[0][0][0][0] = 6; short val6 = get();
+                assertEquals(val6, (isStableEnabled ? 1 : 6));
+            }
+
+            {
+                c.v = new short[1][1][1][1]; short[] val1 = get1();
+                c.v[0][0][0] = new short[1]; short[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[1][1][1][1]; short[][] val1 = get2();
+                c.v[0][0] = new short[1][1]; short[][] val2 = get2();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[1][1][1][1]; short[][][] val1 = get3();
+                c.v[0] = new short[1][1][1]; short[][][] val2 = get3();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[1][1][1][1]; short[][][][] val1 = get4();
+                c.v = new short[1][1][1][1]; short[][][][] val2 = get4();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+        }
+    }
+
+    /* ==================================================== */
+    // Dynamic Dim is higher than static
+
+    static class ObjectArrayLowerDim0 {
+        public @Stable Object v;
+
+        public static final ObjectArrayLowerDim0 c = new ObjectArrayLowerDim0();
+        public static short get() { return ((short[])c.v)[0]; }
+        public static short[] get1() { return (short[])c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new short[1]; ((short[])c.v)[0] = 1; short val1 = get();
+                                    ((short[])c.v)[0] = 2; short val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new short[1]; short[] val1 = get1();
+                c.v = new short[1]; short[] val2 = get1();
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim1 {
+        public @Stable Object[] v;
+
+        public static final ObjectArrayLowerDim1 c = new ObjectArrayLowerDim1();
+        public static short get() { return ((short[][])c.v)[0][0]; }
+        public static short[] get1() { return (short[])(c.v[0]); }
+        public static Object[] get2() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new short[1][1]; ((short[][])c.v)[0][0] = 1; short val1 = get();
+                                       ((short[][])c.v)[0][0] = 2; short val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new short[1][1]; c.v[0] = new short[0]; short[] val1 = get1();
+                                       c.v[0] = new short[0]; short[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[0][0]; Object[] val1 = get2();
+                c.v = new short[0][0]; Object[] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class ObjectArrayLowerDim2 {
+        public @Stable Object[][] v;
+
+        public static final ObjectArrayLowerDim2 c = new ObjectArrayLowerDim2();
+        public static short get() { return ((short[][][])c.v)[0][0][0]; }
+        public static short[] get1() { return (short[])(c.v[0][0]); }
+        public static short[][] get2() { return (short[][])(c.v[0]); }
+        public static Object[][] get3() { return c.v; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new short[1][1][1]; ((short[][][])c.v)[0][0][0] = 1; short val1 = get();
+                                          ((short[][][])c.v)[0][0][0] = 2; short val2 = get();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, 2);
+            }
+
+            {
+                c.v = new short[1][1][1]; c.v[0][0] = new short[0]; short[] val1 = get1();
+                                          c.v[0][0] = new short[0]; short[] val2 = get1();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[1][1][1]; c.v[0] = new short[0][0]; short[][] val1 = get2();
+                                          c.v[0] = new short[0][0]; short[][] val2 = get2();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+
+            {
+                c.v = new short[0][0][0]; Object[][] val1 = get3();
+                c.v = new short[0][0][0]; Object[][] val2 = get3();
+
+                assertTrue((isStableEnabled ? (val1 == val2) : (val1 != val2)));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField {
+        static class A {
+            public @Stable short a;
+
+        }
+        public @Stable A v;
+
+        public static final NestedStableField c = new NestedStableField();
+        public static A get() { return c.v; }
+        public static short get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.a = 1; A val1 = get();
+                               c.v.a = 2; A val2 = get();
+
+                assertEquals(val1.a, 2);
+                assertEquals(val2.a, 2);
+            }
+
+            {
+                c.v = new A(); c.v.a = 1; short val1 = get1();
+                               c.v.a = 2; short val2 = get1();
+                c.v = new A(); c.v.a = 3; short val3 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField1 {
+        static class A {
+            public @Stable short a;
+            public @Stable A next;
+        }
+        public @Stable A v;
+
+        public static final NestedStableField1 c = new NestedStableField1();
+        public static A get() { return c.v.next.next.next.next.next.next.next; }
+        public static short get1() { return get().a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.next = new A();   c.v.next.next  = c.v;
+                               c.v.a = 1; c.v.next.a = 1; A val1 = get();
+                               c.v.a = 2; c.v.next.a = 2; A val2 = get();
+
+                assertEquals(val1.a, 2);
+                assertEquals(val2.a, 2);
+            }
+
+            {
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 1; short val1 = get1();
+                               c.v.a = 2; short val2 = get1();
+                c.v = new A(); c.v.next = c.v;
+                               c.v.a = 3; short val3 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val2, (isStableEnabled ? 1 : 2));
+                assertEquals(val3, (isStableEnabled ? 1 : 3));
+            }
+        }
+    }
+   /* ==================================================== */
+
+    static class NestedStableField2 {
+        static class A {
+            public @Stable short a;
+            public @Stable A left;
+            public         A right;
+        }
+
+        public @Stable A v;
+
+        public static final NestedStableField2 c = new NestedStableField2();
+        public static short get() { return c.v.left.left.left.a; }
+        public static short get1() { return c.v.left.left.right.left.a; }
+
+        public static void test() throws Exception {
+            {
+                c.v = new A(); c.v.left = c.v.right = c.v;
+                               c.v.a = 1; short val1 = get(); short val2 = get1();
+                               c.v.a = 2; short val3 = get(); short val4 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val3, (isStableEnabled ? 1 : 2));
+
+                assertEquals(val2, 1);
+                assertEquals(val4, 2);
+            }
+        }
+    }
+
+    /* ==================================================== */
+
+    static class NestedStableField3 {
+        static class A {
+            public @Stable short a;
+            public @Stable A[] left;
+            public         A[] right;
+        }
+
+        public @Stable A[] v;
+
+        public static final NestedStableField3 c = new NestedStableField3();
+        public static short get() { return c.v[0].left[1].left[0].left[1].a; }
+        public static short get1() { return c.v[1].left[0].left[1].right[0].left[1].a; }
+
+        public static void test() throws Exception {
+            {
+                A elem = new A();
+                c.v = new A[] { elem, elem }; c.v[0].left = c.v[0].right = c.v;
+                               elem.a = 1; short val1 = get(); short val2 = get1();
+                               elem.a = 2; short val3 = get(); short val4 = get1();
+
+                assertEquals(val1, 1);
+                assertEquals(val3, (isStableEnabled ? 1 : 2));
+
+                assertEquals(val2, 1);
+                assertEquals(val4, 2);
+            }
+        }
+    }
+
+    /* ==================================================== */
+    // Auxiliary methods
+    static void assertEquals(int i, int j) { if (i != j)  throw new AssertionError(i + " != " + j); }
+    static void assertTrue(boolean b) { if (!b)  throw new AssertionError(); }
+
+    static boolean failed = false;
+
+    public static void run(Class<?> test) {
+        Throwable ex = null;
+        System.out.print(test.getName()+": ");
+        try {
+            test.getMethod("test").invoke(null);
+        } catch (InvocationTargetException e) {
+            ex = e.getCause();
+        } catch (Throwable e) {
+            ex = e;
+        } finally {
+            if (ex == null) {
+                System.out.println("PASSED");
+            } else {
+                failed = true;
+                System.out.println("FAILED");
+                ex.printStackTrace(System.out);
+            }
+        }
+    }
+
+    static final boolean isStableEnabled;
+    static {
+        HotSpotDiagnosticMXBean diagnostic
+                = ManagementFactoryHelper.getDiagnosticMXBean();
+        VMOption tmp;
+        try {
+            tmp = diagnostic.getVMOption("FoldStableValues");
+        } catch (IllegalArgumentException e) {
+            tmp = null;
+        }
+        isStableEnabled = (tmp == null ? false : Boolean.parseBoolean(tmp.getValue()));
+    }
+}