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
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 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.StableRefPlainTest
 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 StableRefPlainTest {
 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 INTEGER = 42;
 59 
 60     static class Carrier {
 61         @Stable
 62         Integer field;
 63 
 64         @ForceInline
 65         public Carrier(boolean init) {
 66             if (init) {
 67                 field = INTEGER;
 68             }
 69         }
 70 
 71         @ForceInline
 72         public void init() {
 73             field = INTEGER;
 74         }
 75     }
 76 
 77     static final Carrier BLANK_CARRIER = new Carrier(false);
 78     static final Carrier INIT_CARRIER = new Carrier(true);
 79 
 80     @Test
 81     @IR(counts = { IRNode.LOAD, ">0" })
 82     @IR(applyIf = {"enable-valhalla", "false"}, failOn = { IRNode.MEMBAR })
 83     // We have barriers with valhalla from the atomic expansion of the LoadFlatNode
 84     // Indeed, since the field is not initialized, it is not known to be constant yet,
 85     // and so, the LoadFlat cannot be expanded non-atomically. We need barriers to synchronize
 86     // the LoadFlat and potential updates to sub-field of the flatten field.
 87     @IR(applyIfAnd = {"UseFieldFlattening", "true", "enable-valhalla", "true"}, counts = { IRNode.MEMBAR, ">0" })
 88     static int testNoFold() {
 89         // Access should not be folded.
 90         Integer i = BLANK_CARRIER.field;
 91         return i != null ? i : 0;
 92     }
 93 
 94     @Test
 95     @IR(failOn = { IRNode.LOAD, IRNode.MEMBAR })
 96     static int testFold() {
 97         // Access should be completely folded.
 98         Integer i = INIT_CARRIER.field;
 99         return i != null ? i : 0;
100     }
101 
102     @Test
103     @IR(counts = { IRNode.MEMBAR_STORESTORE, "1" })
104     static Carrier testConstructorBlankInit() {
105         // Only the header barrier.
106         return new Carrier(false);
107     }
108 
109     @Test
110     @IR(counts = { IRNode.MEMBAR_STORESTORE, "1" })
111     static Carrier testConstructorFullInit() {
112         // Only the header barrier.
113         return new Carrier(true);
114     }
115 
116     @Test
117     @IR(applyIf = {"enable-valhalla", "false"}, failOn = { IRNode.MEMBAR })
118     // We have barriers from the atomic expansion of the StoreFlatNode. Store is not eliminated with
119     // or without Valhalla, but Valhalla's StoreFlat require barriers.
120     @IR(applyIfAnd = {"UseFieldFlattening", "true", "enable-valhalla", "true"}, counts = { IRNode.MEMBAR, ">0" })
121     static void testMethodInit() {
122         INIT_CARRIER.init();
123     }
124 
125 }