1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
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17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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23 
24 /**
25  * @test
26  * @bug 8078426
27  * @summary split if finds predicates on several incoming paths when unswitched's loops are optimized out
28  *
29  * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-UseOnStackReplacement
30  *                   -XX:-BackgroundCompilation -XX:-UseCompressedOops
31  *                   compiler.loopopts.TestSplitIfUnswitchedLoopsEliminated
32  */
33 
34 package compiler.loopopts;
35 
36 public class TestSplitIfUnswitchedLoopsEliminated {
37 
38     static class A {
39         int f;
40     }
41 
42     static A aa = new A();
43     static A aaa = new A();
44 
test_helper(int stop, boolean unswitch)45     static int test_helper(int stop, boolean unswitch) {
46         A a = null;
47         for (int i = 3; i < 10; i++) {
48             if (unswitch) {
49                 a = null;
50             } else {
51                 a = aa;
52                 int v = a.f;
53             }
54         }
55         if (stop != 4) {
56             a = aaa;
57         }
58         if (a != null) {
59             return a.f;
60         }
61         return 0;
62     }
63 
test(boolean unswitch)64     static int test(boolean unswitch) {
65         int stop = 1;
66         for (; stop < 3; stop *= 4) {
67         }
68         return test_helper(stop, unswitch);
69     }
70 
main(String[] args)71     public static void main(String[] args) {
72         for (int i = 0; i < 20000; i++) {
73             test_helper(10, i%2 == 0);
74             test(i%2 == 0);
75         }
76     }
77 }
78