8319973: AArch64: Save and restore FPCR in the call stub

[bulasevich]

Clean backport to ensure correct FPCR handling and to avoid unexpected behavior. Applying it to earlier releases will ensure stability and consistency across all versions. As a next step, I will propose a backport for JDK-8320892, which depends on this change.

JDK-8319973: AArch64: Save and restore FPCR in the call stub
JDK-8320892: AArch64: Restore FPU control state after JNI

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8319973 needs maintainer approval

Issue

• JDK-8319973: AArch64: Save and restore FPCR in the call stub (Bug - P3 - Approved) ⚠️ Issue is already resolved. Consider making this a "backport pull request" by setting the PR title to Backport <hash> with the hash of the original commit. See Backports.

Reviewers

• Andrew Haley (@theRealAph - Reviewer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/1042/head:pull/1042
$ git checkout pull/1042

Update a local copy of the PR:
$ git checkout pull/1042
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/1042/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 1042

View PR using the GUI difftool:
$ git pr show -t 1042

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Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/1042.diff

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Link to Webrev Comment

[bridgekeeper]

👋 Welcome back bulasevich! 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]

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

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

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

8319973: AArch64: Save and restore FPCR in the call stub

Reviewed-by: aph

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 13 new commits pushed to the master branch:

• eaf1f67: 8340632: ProblemList java/nio/channels/DatagramChannel/ for Macos
• 4de0f30: 8323688: C2: Fix UB of jlong overflow in PhaseIdealLoop::is_counted_loop()
• 21d7353: 8340008: KeyEvent/KeyTyped/Numpad1KeyTyped.java has 15 seconds timeout
• 5f34b72: 8337067: Test runtime/classFileParserBug/Bad_NCDFE_Msg.java won't compile
• b7efb79: 8321543: Update NSS to version 3.96
• 8648dcc: 8321299: runtime/logging/ClassLoadUnloadTest.java doesn't reliably trigger class unloading
• eb6a23a: 8337876: [IR Framework] Add support for IR tests with @stable
• 3efdcde: 8340590: RISC-V: C2: Small improvement to vector gather load and scatter store
• 21fec60: 8332461: ubsan : dependencies.cpp:906:3: runtime error: load of value 4294967295, which is not a valid value for type 'DepType'
• 10665ba: 8341562: RISC-V: Generate comments in -XX:+PrintInterpreter to link to source code
• ... and 3 more: https://git.openjdk.org/jdk21u-dev/compare/978075f67da50403105726105f5aa22fecd9149c...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change. Possible candidates are the reviewers of this PR (@theRealAph) but any other Committer may sponsor as well.

➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[mlbridge]

Webrevs

• 00: Full (71de5206)

[theRealAph]

Yes, I think so. There is no compatibility issue here, because this patch is necessary to ensure standard-compatible behavior in all cases. Thanks.

[openjdk]

⚠️ @bulasevich This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[bulasevich]

/approval request
Clean backport to ensure correct FPCR handling and to avoid unexpected behavior. Applying it to earlier releases will ensure stability and consistency across all versions.

[openjdk]

@bulasevich
8319973: The approval request has been created successfully.

[GoeLin]

I am wondering why this is not recognized clean.

[bulasevich]

I am wondering why this is not recognized clean.

I do not think I did anything wrong. Automatic patch applied cleanly and jtreg tier1-3 tests are OK.

boris@jdk21u-dev$ (cd ../jdk-trunk ; git show 6e86904a94d2ed2815aa6e3364c048dac595320d) | patch -p1
patching file src/hotspot/cpu/aarch64/assembler_aarch64.hpp
patching file src/hotspot/cpu/aarch64/frame_aarch64.hpp
patching file src/hotspot/cpu/aarch64/macroAssembler_aarch64.hpp
Hunk #1 succeeded at 570 (offset -1 lines).
patching file src/hotspot/cpu/aarch64/stubGenerator_aarch64.cpp
Hunk #1 succeeded at 136 (offset -5 lines).
Hunk #2 succeeded at 169 (offset -5 lines).
Hunk #3 succeeded at 201 (offset -5 lines).
Hunk #4 succeeded at 252 (offset -5 lines).
Hunk #5 succeeded at 373 (offset -5 lines).
boris@jdk21u-dev$ git commit -m "Backport 6e86904a94d2ed2815aa6e3364c048dac595320d" src

[bulasevich]

/integrate

[openjdk]

@bulasevich
Your change (at version 71de520) is now ready to be sponsored by a Committer.

[phohensee]

/sponsor

[openjdk]

Going to push as commit 9e582fc.
Since your change was applied there have been 13 commits pushed to the master branch:

• eaf1f67: 8340632: ProblemList java/nio/channels/DatagramChannel/ for Macos
• 4de0f30: 8323688: C2: Fix UB of jlong overflow in PhaseIdealLoop::is_counted_loop()
• 21d7353: 8340008: KeyEvent/KeyTyped/Numpad1KeyTyped.java has 15 seconds timeout
• 5f34b72: 8337067: Test runtime/classFileParserBug/Bad_NCDFE_Msg.java won't compile
• b7efb79: 8321543: Update NSS to version 3.96
• 8648dcc: 8321299: runtime/logging/ClassLoadUnloadTest.java doesn't reliably trigger class unloading
• eb6a23a: 8337876: [IR Framework] Add support for IR tests with @stable
• 3efdcde: 8340590: RISC-V: C2: Small improvement to vector gather load and scatter store
• 21fec60: 8332461: ubsan : dependencies.cpp:906:3: runtime error: load of value 4294967295, which is not a valid value for type 'DepType'
• 10665ba: 8341562: RISC-V: Generate comments in -XX:+PrintInterpreter to link to source code
• ... and 3 more: https://git.openjdk.org/jdk21u-dev/compare/978075f67da50403105726105f5aa22fecd9149c...master

Your commit was automatically rebased without conflicts.

[openjdk]

@phohensee @bulasevich Pushed as commit 9e582fc.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.