1 /*
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  4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  7  * under the terms of the GNU General Public License version 2 only, as
  8  * published by the Free Software Foundation.
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 10  * This code is distributed in the hope that it will be useful, but WITHOUT
 11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 13  * version 2 for more details (a copy is included in the LICENSE file that
 14  * accompanied this code).
 15  *
 16  * You should have received a copy of the GNU General Public License version
 17  * 2 along with this work; if not, write to the Free Software Foundation,
 18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 19  *
 20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 21  * or visit www.oracle.com if you need additional information or have any
 22  * questions.
 23  */
 24 
 25 /*
 26  * @test
 27  * @bug 8333791
 28  * @requires os.arch=="aarch64" | os.arch=="riscv64" | os.arch=="x86_64" | os.arch=="amd64"
 29  * @requires vm.gc.Parallel
 30  * @requires vm.compiler2.enabled
 31  * @summary Check stable field folding and barriers
 32  * @modules java.base/jdk.internal.vm.annotation
 33  * @library /test/lib /
 34  * @run driver compiler.c2.irTests.stable.StableRefArrayTest
 35  */
 36 
 37 package compiler.c2.irTests.stable;
 38 
 39 import compiler.lib.ir_framework.*;
 40 import jdk.test.lib.Asserts;
 41 
 42 import jdk.internal.vm.annotation.Stable;
 43 
 44 public class StableRefArrayTest {
 45 
 46     public static void main(String[] args) {
 47         TestFramework tf = new TestFramework();
 48         tf.addTestClassesToBootClassPath();
 49         tf.addFlags(
 50             "-XX:+UnlockExperimentalVMOptions",
 51             "-XX:CompileThreshold=100",
 52             "-XX:-TieredCompilation",
 53             "-XX:+UseParallelGC"
 54         );
 55         tf.start();
 56     }
 57 
 58     static final Integer[] EMPTY_INTEGER = new Integer[] { null };
 59     static final Integer[] FULL_INTEGER = new Integer[] { 42 };
 60 
 61     static class Carrier {
 62         @Stable
 63         Integer[] field;
 64 
 65         @ForceInline
 66         public Carrier(int initLevel) {
 67             switch (initLevel) {
 68                 case 0:
 69                     // Do nothing.
 70                     break;
 71                 case 1:
 72                     field = EMPTY_INTEGER;
 73                     break;
 74                 case 2:
 75                     field = FULL_INTEGER;
 76                     break;
 77                 default:
 78                     throw new IllegalStateException("Unknown level");
 79             }
 80         }
 81 
 82         @ForceInline
 83         public void initEmpty() {
 84             field = EMPTY_INTEGER;
 85         }
 86 
 87         @ForceInline
 88         public void initFull() {
 89             field = FULL_INTEGER;
 90         }
 91 
 92     }
 93 
 94     static final Carrier BLANK_CARRIER = new Carrier(0);
 95     static final Carrier INIT_EMPTY_CARRIER = new Carrier(1);
 96     static final Carrier INIT_FULL_CARRIER = new Carrier(2);
 97 
 98     @Test
 99     @IR(counts = { IRNode.LOAD, ">0" })
100     @IR(failOn = { IRNode.MEMBAR })
101     static int testNoFold() {
102         // Access should not be folded.
103         // No barriers expected for plain fields.
104         Integer[] is = BLANK_CARRIER.field;
105         if (is != null) {
106             Integer i = is[0];
107             if (i != null) {
108                 return i;
109             }
110         }
111         return 0;
112     }
113 
114     @Test
115     @IR(counts = { IRNode.LOAD, ">0" })
116     @IR(applyIf = {"enable-valhalla", "false"}, failOn = { IRNode.MEMBAR })
117     // We have barriers with valhalla from the atomic expansion of the LoadFlatNode
118     // Indeed, since the array element is not initialized, it is not known to be constant yet,
119     // and so, the LoadFlat cannot be expanded non-atomically. We need barriers to synchronize
120     // the LoadFlat and potential updates to field of the flatten array element.
121     @IR(applyIfAnd = {"UseArrayFlattening", "true", "enable-valhalla", "true"}, counts = { IRNode.MEMBAR, "> 0" })
122     static int testPartialFold() {
123         // Access should not be folded.

124         Integer[] is = INIT_EMPTY_CARRIER.field;
125         if (is != null) {
126             Integer i = is[0];
127             if (i != null) {
128                 return i;
129             }
130         }
131         return 0;
132     }
133 
134 
135     @Test
136     @IR(failOn = { IRNode.LOAD, IRNode.MEMBAR })
137     static int testFold() {
138         // Access should be completely folded.
139         Integer[] is = INIT_FULL_CARRIER.field;
140         if (is != null) {
141             Integer i = is[0];
142             if (i != null) {
143                 return i;
144             }
145         }
146         return 0;
147     }
148 
149     @Test
150     @IR(counts = { IRNode.MEMBAR_STORESTORE, "1" })
151     static Carrier testConstructorBlankInit() {
152         // Only the header barrier.
153         return new Carrier(0);
154     }
155 
156     @Test
157     @IR(counts = { IRNode.MEMBAR_STORESTORE, "1" })
158     static Carrier testConstructorEmptyInit() {
159         // Only the header barrier.
160         return new Carrier(1);
161     }
162 
163     @Test
164     @IR(counts = { IRNode.MEMBAR_STORESTORE, "1" })
165     static Carrier testConstructorFullInit() {
166         // Only the header barrier.
167         return new Carrier(2);
168     }
169 
170     @Test
171     @IR(failOn = { IRNode.MEMBAR })
172     static void testMethodEmptyInit() {
173         // Reference inits do not have membars.
174         INIT_EMPTY_CARRIER.initEmpty();
175     }
176 
177     @Test
178     @IR(failOn = { IRNode.MEMBAR })
179     static void testMethodFullInit() {
180         // Reference inits do not have membars.
181         INIT_FULL_CARRIER.initFull();
182     }
183 
184 }
--- EOF ---