8277239: SIGSEGV in vrshift_reg_maskedNode::emit

[jatin-bhateja]

Currently instruction selector differentiates between the two kinds of vector shift operations i.e. one with vector shift count and other with scalar shift count passed though LShiftCntV/RShiftCntV nodes by looking at the ideal opcode of shift count node.

A more robust scheme is to set a flag over vector shift node if it has variable vector shift count and replace the opcode based check with flag based check in various shift instruction selection patterns.

---

Progress

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Issue

• JDK-8277239: SIGSEGV in vrshift_reg_maskedNode::emit

Reviewers

• Sandhya Viswanathan (@sviswa7 - Reviewer) ⚠️ Review applies to 97dce5c
• Dean Long (@dean-long - Reviewer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk pull/6431/head:pull/6431
$ git checkout pull/6431

Update a local copy of the PR:
$ git checkout pull/6431
$ git pull https://git.openjdk.java.net/jdk pull/6431/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 6431

View PR using the GUI difftool:
$ git pr show -t 6431

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk/pull/6431.diff

[bridgekeeper]

👋 Welcome back jbhateja! 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.

[jatin-bhateja]

/label hotspot-compiler-dev

[openjdk]

@jatin-bhateja
The hotspot-compiler label was successfully added.

[mlbridge]

Webrevs

• 01: Full - Incremental (41d33df0)
• 00: Full (97dce5ca)

[PaulSandoz]

Running tests to verify.

[sviswa7]

The patch looks good to me.

[openjdk]

@jatin-bhateja 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:

8277239: SIGSEGV in vrshift_reg_maskedNode::emit

Reviewed-by: sviswanathan, dlong

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 90 new commits pushed to the master branch:

• 8051041: 8277534: Remove unused ReferenceProcessor::has_discovered_references
• 3f847fe: 8277385: Zero: Enable CompactStrings support
• ca31ed5: 8275448: [REDO] AArch64: Implement string_compare intrinsic in SVE
• 4ff4301: 8224922: Access JavaFileObject from Element(s)
• 0a9e76c: 8277485: Zero: Fix fast{i,f}access_0 bytecodes handling
• 1c215f3: 8272773: Configurable card table card size
• 1d7cef3: 8276662: Scalability bottleneck in SymbolTable::lookup_common()
• c79a485: 8277494: [BACKOUT] JDK-8276150 Quarantined jpackage apps are labeled as "damaged"
• 2ab43ec: 8273544: Increase test coverage for snippets
• 2d4af22: 8277370: configure script cannot distinguish WSL version
• ... and 80 more: https://git.openjdk.java.net/jdk/compare/bd92674be563ad291990216b7cdf061c498f5dd3...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.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[PaulSandoz]

Tests passed. Needs another HotSpot reviewer.

[dean-long]

how about moving this down to where it is used?

[jatin-bhateja]

Thanks @sviswa7 and @dean-long

[jatin-bhateja]

/integrate

[openjdk]

Going to push as commit e529865.
Since your change was applied there have been 94 commits pushed to the master branch:

• 8683de5: 8274685: Documentation suggests there are ArbitrarilyJumpableGenerator when none
• 6b4fbae: 8273792: JumpableGenerator.rngs() documentation refers to wrong method
• d427c79: 8277428: G1: Move and inline G1STWIsAliveClosure::do_object_b
• 32839ba: 8266593: vmTestbase/nsk/jvmti/PopFrame/popframe011 fails with "assert(java_thread == _state->get_thread()) failed: Must be"
• 8051041: 8277534: Remove unused ReferenceProcessor::has_discovered_references
• 3f847fe: 8277385: Zero: Enable CompactStrings support
• ca31ed5: 8275448: [REDO] AArch64: Implement string_compare intrinsic in SVE
• 4ff4301: 8224922: Access JavaFileObject from Element(s)
• 0a9e76c: 8277485: Zero: Fix fast{i,f}access_0 bytecodes handling
• 1c215f3: 8272773: Configurable card table card size
• ... and 84 more: https://git.openjdk.java.net/jdk/compare/bd92674be563ad291990216b7cdf061c498f5dd3...master

Your commit was automatically rebased without conflicts.

[openjdk]

@jatin-bhateja Pushed as commit e529865.

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