RFR: 8283422: Create a new test for JDK-8254790 [v2]

[Sergey Bylokhov]

On Mon, 28 Mar 2022 20:30:35 GMT, Sergey Bylokhov <serb at openjdk.org> wrote:

>> The [JDK-8254790](https://bugs.openjdk.java.net/browse/JDK-8254790) initially was reported on macOS.
>> It was found by the "javax/xml/crypto/dsig/GenerationTests.java" test which for some reason worked fine on Linux/Windows most? of the time.
>> 
>> I tried to run that test on Linux/Windows many times on a few systems and it always pass. Also, I got the same result for the tier1...tier4 tests.
>> 
>> I have found that the easiest way to reproduce the crash is to pass the result of the string.indexOf to the str.charAt when the heap is big enough. The test below[1] trigger the crash 1000 time in a row on win/lin on systems I have tested.
>> 
>> I am not sure what is the best way to contribute to the test, should I create a stand-alone test like[1], or update an existing test as I did for the first version of this PR?
>> 
>> [1]:
>> 
>> package compiler.intrinsics.string;
>> 
>> import static jdk.test.lib.Asserts.assertTrue;
>> 
>> public final class TestStringIndexOfLargeHeap {
>>     static final int[] data = new int[Integer.MAX_VALUE / 2];
>>     public static void main(String[] args) throws Exception {
>>         test('a');
>>         test('\ubeef');
>>     }
>>     private static void test(char ch) {
>>         String str = ("0123456789" + ch).repeat(100);
>>         for (int i = 0; i < 1_000_000; ++i) {
>>             assertTrue(ch == str.charAt(str.indexOf(ch)));
>>         }
>>     }
>> }
>
> Sergey Bylokhov has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:
> 
>  - Request 8G of heap
>  - Merge branch 'master' into JDK-8283422
>  - Add vm.bits == "64"
>  - Initial version

I have found the bug where some tests tried to allocate same huge amount of memory and fail:
https://bugs.openjdk.java.net/browse/JDK-8227645
The solution was to move them to the special folder "hotspot/jtreg/resourcehogs" so they will have "exclusiveAccess" flag.
I'll "move" the new test there.

-------------

PR: https://git.openjdk.java.net/jdk/pull/7883