February 2021 - core-libs-dev

RFR: 8253795: Implementation of JEP 391: macOS/AArch64 Port
by Anton Kozlov 25 Mar '21

25 Mar '21

Please review the implementation of JEP 391: macOS/AArch64 Port. It's heavily based on existing ports to linux/aarch64, macos/x86_64, and windows/aarch64. Major changes are in: * src/hotspot/cpu/aarch64: support of the new calling convention (subtasks JDK-8253817, JDK-8253818) * src/hotspot/os_cpu/bsd_aarch64: copy of os_cpu/linux_aarch64 with necessary adjustments (JDK-8253819) * src/hotspot/share, test/hotspot/gtest: support of write-xor-execute (W^X), required on macOS/AArch64 platform. It's implemented with pthread_jit_write_protect_np provided by Apple. The W^X mode is local to a thread, so W^X mode change relates to the java thread state change (for java threads). In most cases, JVM executes in write-only mode, except when calling a generated stub like SafeFetch, which requires a temporary switch to execute-only mode. The same execute-only mode is enabled when a java thread executes in java or native states. This approach of managing W^X mode turned out to be simple and efficient enough. * src/jdk.hotspot.agent: serviceability agent implementation (JDK-8254941) ------------- Commit messages: - Fix build - JDK-8253816: Update after recent changes - Rework gtests to always have wx_write - Revert gtest changes - Fix gtests in debug - Merge remote-tracking branch 'upstream/master' into jdk-macos - Fix windows_aarch64 - Use r18_tls instead of r18_reserved - JDK-8253742: bsd_aarch64 part - JDK-8257882: bsd_aarch64 part - ... and 40 more: https://git.openjdk.java.net/jdk/compare/82adfb32...3d4f4c23 Changes: https://git.openjdk.java.net/jdk/pull/2200/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2200&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8253795 Stats: 3335 lines in 117 files changed: 3230 ins; 41 del; 64 mod Patch: https://git.openjdk.java.net/jdk/pull/2200.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2200/head:pull/2200 PR: https://git.openjdk.java.net/jdk/pull/2200

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Class.getRecordComponents security checks
by Attila Szegedi 20 Mar '21

20 Mar '21

Hey folks, Why are security checks for Class.getRecordComponents as strict as those for e.g. getDeclaredMethods? I would’ve expected they’d be as strict as those for e.g. getMethods. Specifically, the difference is the: > “the caller's class loader is not the same as the class loader of this class and invocation of s.checkPermission method with RuntimePermission("accessDeclaredMembers") denies access to the declared methods within this class” step. Aren’t record accessors supposed to be public? Attila.

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RFR: 8260605: Various java.lang.invoke cleanups
by Claes Redestad 18 Mar '21

18 Mar '21

- Remove unused code - Inline and simplify the bootstrap method invocation code (remove pointless reboxing checks etc) - Apply pattern matching to make some code more readable ------------- Commit messages: - Avoid unnecessary reboxing checks, inline and simplify class/mt invokes - j.l.invoke cleanups Changes: https://git.openjdk.java.net/jdk/pull/2300/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2300&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8260605 Stats: 269 lines in 14 files changed: 11 ins; 161 del; 97 mod Patch: https://git.openjdk.java.net/jdk/pull/2300.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2300/head:pull/2300 PR: https://git.openjdk.java.net/jdk/pull/2300

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RFR: 8148937: (str) Adapt StringJoiner for Compact Strings
by Сергей Цыпанов 17 Mar '21

17 Mar '21

Hello, as of now `java.util.StringJoiner` still uses `char[]` as a storage for joined Strings. This applies for the cases when all joined Strings as well as delimiter, prefix and suffix contain only ASCII symbols. As a result when `StringJoiner.toString()` is called `byte[]` stored in Strings is inflated in order to fill in `char[]` and after that `char[]` is compressed when constructor of String is called: String delimiter = this.delimiter; char[] chars = new char[this.len + addLen]; int k = getChars(this.prefix, chars, 0); if (size > 0) { k += getChars(elts[0], chars, k); // inflate byte[] for(int i = 1; i < size; ++i) { k += getChars(delimiter, chars, k); k += getChars(elts[i], chars, k); } } k += getChars(this.suffix, chars, k); return new String(chars); // compress char[] -> byte[] This can be improved by utilizing new method `String.getBytes(byte[], int, int, byte, int)` [introduced](https://github.com/openjdk/jdk/pull/402) in [JDK-8224986](https://bugs.openjdk.java.net/browse/JDK-8254082) covering both cases when resulting String is Latin1 or UTF-16 I've prepared a patch along with benchmark proving that this change is correct and brings improvement. @BenchmarkMode(Mode.AverageTime) @OutputTimeUnit(TimeUnit.NANOSECONDS) @Fork(jvmArgsAppend = {"-Xms2g", "-Xmx2g"}) public class StringJoinerBenchmark { @Benchmark public String stringJoiner(Data data) { String[] stringArray = data.stringArray; return Joiner.joinWithStringJoiner(stringArray); } @State(Scope.Thread) public static class Data { @Param({"latin", "cyrillic", "mixed"}) private String mode; @Param({"8", "32", "64"}) private int length; @Param({"5", "10", "100"}) private int count; private String[] stringArray; @Setup public void setup() { RandomStringGenerator generator = new RandomStringGenerator(); stringArray = new String[count]; for (int i = 0; i < count; i++) { String alphabet = getAlphabet(i, mode); stringArray[i] = generator.randomString(alphabet, length); } } private static String getAlphabet(int index, String mode) { var latin = "abcdefghijklmnopqrstuvwxyz"; //English var cyrillic = "абвгдеёжзиклмнопрстуфхцчшщьыъэюя"; // Russian String alphabet; switch (mode) { case "mixed" -> alphabet = index % 2 == 0 ? cyrillic : latin; case "latin" -> alphabet = latin; case "cyrillic" -> alphabet = cyrillic; default -> throw new RuntimeException("Illegal mode " + mode); } return alphabet; } } } (count) (length) (mode) Java 14 patched Units stringJoiner 5 8 latin 78.836 ± 0.208 67.546 ± 0.500 ns/op stringJoiner 5 32 latin 92.877 ± 0.422 66.760 ± 0.498 ns/op stringJoiner 5 64 latin 115.423 ± 0.883 73.224 ± 0.289 ns/op stringJoiner 10 8 latin 152.587 ± 0.429 161.427 ± 0.635 ns/op stringJoiner 10 32 latin 189.998 ± 0.478 164.099 ± 0.963 ns/op stringJoiner 10 64 latin 238.679 ± 1.419 176.825 ± 0.533 ns/op stringJoiner 100 8 latin 1215.612 ± 17.413 1541.802 ± 126.166 ns/op stringJoiner 100 32 latin 1699.998 ± 28.407 1563.341 ± 4.439 ns/op stringJoiner 100 64 latin 2289.388 ± 45.319 2215.931 ± 137.583 ns/op stringJoiner 5 8 cyrillic 96.692 ± 0.947 80.946 ± 0.371 ns/op stringJoiner 5 32 cyrillic 107.806 ± 0.429 84.717 ± 0.541 ns/op stringJoiner 5 64 cyrillic 150.762 ± 2.267 96.214 ± 1.251 ns/op stringJoiner 10 8 cyrillic 190.570 ± 0.381 182.754 ± 0.678 ns/op stringJoiner 10 32 cyrillic 240.239 ± 1.110 187.991 ± 1.575 ns/op stringJoiner 10 64 cyrillic 382.493 ± 2.692 219.358 ± 0.967 ns/op stringJoiner 100 8 cyrillic 1737.435 ± 16.171 1658.379 ± 56.225 ns/op stringJoiner 100 32 cyrillic 2321.106 ± 13.583 1942.028 ± 3.418 ns/op stringJoiner 100 64 cyrillic 3189.563 ± 10.135 2484.796 ± 7.572 ns/op stringJoiner 5 8 mixed 88.743 ± 0.709 76.049 ± 0.685 ns/op stringJoiner 5 32 mixed 103.425 ± 0.745 81.006 ± 0.184 ns/op stringJoiner 5 64 mixed 146.441 ± 0.763 93.071 ± 0.858 ns/op stringJoiner 10 8 mixed 169.262 ± 0.482 158.890 ± 0.598 ns/op stringJoiner 10 32 mixed 218.566 ± 0.945 170.415 ± 1.172 ns/op stringJoiner 10 64 mixed 361.412 ± 1.546 200.374 ± 0.683 ns/op stringJoiner 100 8 mixed 1594.544 ± 5.761 1476.689 ± 2.004 ns/op stringJoiner 100 32 mixed 2221.333 ± 28.320 1879.071 ± 52.729 ns/op stringJoiner 100 64 mixed 3115.786 ± 22.485 2400.644 ± 4.401 ns/op stringJoiner:·gc.alloc.rate.norm 5 8 latin 248.023 ± 0.001 136.015 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 32 latin 608.045 ± 0.001 256.022 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 64 latin 1088.067 ± 0.002 416.030 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 8 latin 464.044 ± 0.001 264.029 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 32 latin 1184.085 ± 0.003 504.044 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 64 latin 2144.123 ± 0.005 824.065 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 100 8 latin 3872.367 ± 8.002 2024.269 ± 8.016 B/op stringJoiner:·gc.alloc.rate.norm 100 32 latin 11048.803 ± 7.988 4416.393 ± 0.004 B/op stringJoiner:·gc.alloc.rate.norm 100 64 latin 20657.194 ± 9.775 7640.642 ± 9.819 B/op stringJoiner:·gc.alloc.rate.norm 5 8 cyrillic 360.029 ± 0.001 184.020 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 32 cyrillic 960.060 ± 0.002 424.032 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 64 cyrillic 1760.088 ± 0.003 744.043 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 8 cyrillic 664.063 ± 0.001 352.038 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 32 cyrillic 1864.128 ± 0.003 832.067 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 64 cyrillic 3464.206 ± 0.007 1472.094 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 100 8 cyrillic 5704.541 ± 0.006 2928.317 ± 8.002 B/op stringJoiner:·gc.alloc.rate.norm 100 32 cyrillic 17705.090 ± 0.045 7720.658 ± 0.007 B/op stringJoiner:·gc.alloc.rate.norm 100 64 cyrillic 33689.855 ± 9.786 14121.042 ± 0.015 B/op stringJoiner:·gc.alloc.rate.norm 5 8 mixed 360.028 ± 0.001 184.016 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 32 mixed 960.059 ± 0.002 424.031 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 64 mixed 1760.088 ± 0.003 744.041 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 8 mixed 664.052 ± 0.001 352.035 ± 0.002 B/op stringJoiner:·gc.alloc.rate.norm 10 32 mixed 1864.116 ± 0.005 832.064 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 64 mixed 3464.196 ± 0.006 1472.088 ± 0.002 B/op stringJoiner:·gc.alloc.rate.norm 100 8 mixed 5672.448 ± 8.002 2920.314 ± 0.006 B/op stringJoiner:·gc.alloc.rate.norm 100 32 mixed 17681.092 ± 9.824 7728.653 ± 8.008 B/op stringJoiner:·gc.alloc.rate.norm 100 64 mixed 33697.818 ± 8.011 14120.977 ± 0.034 B/op ------------- Commit messages: - 8261880: Check also delimiter, prefix and suffix - 8148937: (str) Adapt StringJoiner for Compact Strings Changes: https://git.openjdk.java.net/jdk/pull/2627/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2627&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8148937 Stats: 77 lines in 3 files changed: 56 ins; 6 del; 15 mod Patch: https://git.openjdk.java.net/jdk/pull/2627.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2627/head:pull/2627 PR: https://git.openjdk.java.net/jdk/pull/2627

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RFR: 8259925: [Vector API] Unreasonable IndexOutOfBoundsException message when length < vlen
by Jie Fu 17 Mar '21

17 Mar '21

Hi all, For this reproducer: import jdk.incubator.vector.ByteVector; import jdk.incubator.vector.VectorSpecies; public class Test { static final VectorSpecies<Byte> SPECIES_128 = ByteVector.SPECIES_128; static byte[] a = new byte[8]; static byte[] b = new byte[8]; public static void main(String[] args) { ByteVector av = ByteVector.fromArray(SPECIES_128, a, 0); av.intoArray(b, 0); System.out.println("b: " + b[0]); } } The following IndexOutOfBoundsException message (length -7) is unreasonable. Exception in thread "main" java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length -7 It might be better to fix it like this. Exception in thread "main" java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0 Thanks. Best regards, Jie ------------- Commit messages: - 8259925: [Vector API] Unreasonable IndexOutOfBoundsException message when length < vlen Changes: https://git.openjdk.java.net/jdk/pull/2127/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2127&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8259925 Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/2127.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2127/head:pull/2127 PR: https://git.openjdk.java.net/jdk/pull/2127

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RFR: 8080272 Refactor I/O stream copying to use java.io.InputStream.transferTo
by Andrey Turbanov 16 Mar '21

16 Mar '21

8080272 Refactor I/O stream copying to use java.io.InputStream.transferTo ------------- Commit messages: - 8080272: Refactor I/O stream copying to use java.io.InputStream.transferTo - 8080272: Refactor I/O stream copying to use java.io.InputStream.transferTo Changes: https://git.openjdk.java.net/jdk/pull/1853/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1853&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8080272 Stats: 319 lines in 26 files changed: 1 ins; 248 del; 70 mod Patch: https://git.openjdk.java.net/jdk/pull/1853.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/1853/head:pull/1853 PR: https://git.openjdk.java.net/jdk/pull/1853

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RFR: 8248862: Implement Enhanced Pseudo-Random Number Generators
by Jim Laskey 15 Mar '21

15 Mar '21

This PR is to introduce a new random number API for the JDK. The primary API is found in RandomGenerator and RandomGeneratorFactory. Further description can be found in the JEP https://openjdk.java.net/jeps/356 . ------------- Commit messages: - 8248862: Implement Enhanced Pseudo-Random Number Generators - Merge branch 'master' into 8248862 - Merge branch 'master' into 8248862 - 8248862: Implement Enhanced Pseudo-Random Number Generators - Merge branch 'master' into 8248862 - 8248862: Implement Enhanced Pseudo-Random Number Generators - 8248862; Implement Enhanced Pseudo-Random Number Generators - Merge branch 'master' into 8248862 - 8248862: Implement Enhanced Pseudo-Random Number Generators - Merge branch 'master' into 8248862 - ... and 27 more: https://git.openjdk.java.net/jdk/compare/9efbb463...7469ca58 Changes: https://git.openjdk.java.net/jdk/pull/1273/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1273&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8248862 Stats: 14875 lines in 31 files changed: 11094 ins; 3704 del; 77 mod Patch: https://git.openjdk.java.net/jdk/pull/1273.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/1273/head:pull/1273 PR: https://git.openjdk.java.net/jdk/pull/1273

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RFR: 8261031: Move some ClassLoader name checking to native/VM
by Claes Redestad 12 Mar '21

12 Mar '21

This patch moves some sanity checking done in ClassLoader.java to the corresponding endpoints in native or VM code. ------------- Commit messages: - Copyrights - Move class name checking for findBootstrapClass/findLoadedClass into native/VM Changes: https://git.openjdk.java.net/jdk/pull/2378/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2378&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8261031 Stats: 20 lines in 3 files changed: 11 ins; 4 del; 5 mod Patch: https://git.openjdk.java.net/jdk/pull/2378.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2378/head:pull/2378 PR: https://git.openjdk.java.net/jdk/pull/2378

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RFR: JDK-8262471: Fix coding style in src/java.base/share/classes/java/lang/CharacterDataPrivateUse.java
by Christoph Göttschkes 10 Mar '21

10 Mar '21

Please review this small patch which fixes the coding style of CharacterDataPrivateUse.java ------------- Commit messages: - Fixes coding style. Changes: https://git.openjdk.java.net/jdk/pull/2754/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2754&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8262471 Stats: 13 lines in 1 file changed: 0 ins; 2 del; 11 mod Patch: https://git.openjdk.java.net/jdk/pull/2754.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2754/head:pull/2754 PR: https://git.openjdk.java.net/jdk/pull/2754

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RFR: 8252399: Update mapMulti documentation to use type test pattern instead of instanceof once JEP 375 exits preview
by Patrick Concannon 09 Mar '21

09 Mar '21

Hi, Could someone please review my changeset for JDK-8252399: 'Update mapMulti documentation to use type test pattern instead of instanceof once JEP 375 exits preview' ? This change updates the example code displayed in the API documentation for mapMulti to use the type test pattern introduced in [JEP375](https://openjdk.java.net/jeps/375). Kind regards, Patrick ------------- Commit messages: - 8252399: Update mapMulti documentation to use type test pattern instead of instanceof once JEP 375 exits preview Changes: https://git.openjdk.java.net/jdk/pull/2544/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2544&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8252399 Stats: 68 lines in 2 files changed: 64 ins; 0 del; 4 mod Patch: https://git.openjdk.java.net/jdk/pull/2544.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2544/head:pull/2544 PR: https://git.openjdk.java.net/jdk/pull/2544

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