RFR: 8367129: Move input validation checks to Java for java.lang.StringLatin1 intrinsics [v2]

[Volkan Yazici]

On Tue, 10 Feb 2026 08:28:58 GMT, Damon Fenacci <dfenacci at openjdk.org> wrote:

>> Volkan Yazici has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Apply review feedback
>
> src/hotspot/share/classfile/vmIntrinsics.hpp line 402:
> 
>> 400:    do_signature(indexOfChar_signature,                           "([BIII)I")                                            \
>> 401:   do_intrinsic(_equalsL,                  java_lang_StringLatin1,equalsS_name, equalsB_signature,                 F_S)  \
>> 402:     do_name(    equalsS_name,                                    "equals0")                                             \
> 
> Suggestion:
> 
>    do_name(    equalsS_name,                                     "equals0")                                             \

Applied the suggestion in 068eb3589a3.

> src/java.base/share/classes/java/lang/StringLatin1.java line 2:
> 
>> 1: /*
>> 2:  * Copyright (c) 2015, 2025, Oracle and/or its affiliates. All rights reserved.
> 
> Suggestion:
> 
>  * Copyright (c) 2015, 2026, Oracle and/or its affiliates. All rights reserved.

Corrected the copyright year in 068eb3589a3.

> Are these additional checks?

Yes. I'm exercising _"Always validate all input at the Java wrapper"_ stated in the parent issue [JDK-8156534].

> I'm asking because I was expecting them to "replace" intrinsics ones but couldn't find where/how

Note the Javadoc of `ArraysSupport#mismatch(byte[] a, byte[] b, int length)`:

    This method does not perform bounds checks. It is the responsibility
    of the caller to perform such bounds checks before calling this method.

AFAICT, `ArraysSupport` should be updated to validate its inputs too. But that is for another day.

> I'm also wondering why they were not there before: did all callers ensure that?

Yes, pretty much accidentally.

[JDK-8156534]: https://bugs.openjdk.org/browse/JDK-8156534

> src/java.base/share/classes/java/lang/StringLatin1.java line 220:
> 
>> 218:     static int compareToUTF16(byte[] value, byte[] other, int len1, int len2) {
>> 219:         Objects.requireNonNull(value);
>> 220:         Objects.requireNonNull(other);
> 
> [Similar question](https://github.com/openjdk/jdk/pull/28832/changes#r2788781455)

Callers were ensuring the validity.

> src/java.base/share/classes/java/lang/StringLatin1.java line 266:
> 
>> 264:     static int compareToCI_UTF16(byte[] value, byte[] other) {
>> 265:         Objects.requireNonNull(value);
>> 266:         Objects.requireNonNull(other);
> 
> [Similar question](https://github.com/openjdk/jdk/pull/28832/changes#r2788781455)

Caller were ensuring the validity.

> src/java.base/share/classes/java/lang/StringUTF16.java line 2:
> 
>> 1: /*
>> 2:  * Copyright (c) 2015, 2025, Oracle and/or its affiliates. All rights reserved.
> 
> Suggestion:
> 
>  * Copyright (c) 2015, 2026, Oracle and/or its affiliates. All rights reserved.

Corrected the copyright year in 068eb3589a3.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/28832#discussion_r2799748646
PR Review Comment: https://git.openjdk.org/jdk/pull/28832#discussion_r2799749747
PR Review Comment: https://git.openjdk.org/jdk/pull/28832#discussion_r2799752709
PR Review Comment: https://git.openjdk.org/jdk/pull/28832#discussion_r2799754246
PR Review Comment: https://git.openjdk.org/jdk/pull/28832#discussion_r2799754534
PR Review Comment: https://git.openjdk.org/jdk/pull/28832#discussion_r2799755812