8279833: Loop optimization issue in String.encodeUTF8_UTF16

[GoeLin]

I backport this for parity with 11.0.15-oracle.

The patch does not apply well.

8259842: Remove Result cache from StringCoding is missing in 11.
Therefore the actual change must be applied to StringCoding.java
and not to String.java. The method encodeUTF8_UTF16() was moved
from the one to the other file in 8259842.

8259842 change also brought the benchmark edited by this change.
I include the whole benchmark in this change. I had to adapt the strings
to compile with 11.

---

Progress

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Issue

• JDK-8279833: Loop optimization issue in String.encodeUTF8_UTF16

Reviewers

• Thomas Stuefe (@tstuefe - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back goetz! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[mlbridge]

Webrevs

• 00: Full (f3dcd764)

[tstuefe]

8259842 change also brought the benchmark edited by this change.
I include the whole benchmark in this change. I had to adapt the strings
to compile with 11.

Could you point out the changed strings please?

Hmm, the test is identical to master. I assume that is what you wanted.

[tstuefe]

LGTM

[openjdk]

@GoeLin This change now passes all automated pre-integration checks.

After integration, the commit message for the final commit will be:

8279833: Loop optimization issue in String.encodeUTF8_UTF16

Reviewed-by: stuefe

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 1 new commit pushed to the master branch:

• e651f09: 8236505: Mark jdk/editpad/EditPadTest.java as @headful

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[GoeLin]

8259842 change also brought the benchmark edited by this change.
I include the whole benchmark in this change. I had to adapt the strings
to compile with 11.

Could you point out the changed strings please?

Hmm, the test is identical to master. I assume that is what you wanted.

The original uses text blocks ("""), I am using normal Strings and '+' to concatenate. The intend is to have the identical String as in master in the end.

[GoeLin]

/integrate

[openjdk]

Going to push as commit 84ed967.
Since your change was applied there have been 4 commits pushed to the master branch:

• 8352e38: 8273277: C2: Move conditional negation into rc_predicate
• 9700ded: 8253197: vmTestbase/nsk/jvmti/StopThread/stopthrd007/TestDescription.java fails with "ERROR: DebuggeeSleepingThread: ThreadDeath lost"
• e279d07: 8236210: javac generates wrong annotation for fields generated from record components
• e651f09: 8236505: Mark jdk/editpad/EditPadTest.java as @headful

Your commit was automatically rebased without conflicts.

[openjdk]

@GoeLin Pushed as commit 84ed967.

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