8286177: C2: "failed: non-reduction loop contains reduction nodes" assert failure

[GoeLin]

I backport this for parity with 17.0.5-oracle.

I had to resolve the removal of the assertion in superword.cpp

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8286177: C2: "failed: non-reduction loop contains reduction nodes" assert failure

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk17u-dev pull/495/head:pull/495
$ git checkout pull/495

Update a local copy of the PR:
$ git checkout pull/495
$ git pull https://git.openjdk.org/jdk17u-dev pull/495/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 495

View PR using the GUI difftool:
$ git pr show -t 495

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk17u-dev/pull/495.diff

[bridgekeeper]

👋 Welcome back goetz! A progress list of the required criteria for merging this PR into pr/494 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

• 01: Full - Incremental (594456fe)
• 00: Full (594456fe)

[GoeLin]

Pre-submit failure: infra issue

[openjdk-notifier]

The dependent pull request has now been integrated, and the target branch of this pull request has been updated. This means that changes from the dependent pull request can start to show up as belonging to this pull request, which may be confusing for reviewers. To remedy this situation, simply merge the latest changes from the new target branch into this pull request by running commands similar to these in the local repository for your personal fork:

git checkout goetz_backport_8286177
git fetch https://git.openjdk.org/jdk17u-dev master
git merge FETCH_HEAD
# if there are conflicts, follow the instructions given by git merge
git commit -m "Merge master"
git push

[GoeLin]

/clean
Change was clean before Skara resolved the dependent pull request

[openjdk]

@GoeLin This backport pull request is now marked as clean

[GoeLin]

Pre-submit failure: infra issue

[openjdk]

@GoeLin 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:

8286177: C2: "failed: non-reduction loop contains reduction nodes" assert failure

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 22 new commits pushed to the master branch:

• dd7ab3d: 8280696: C2 compilation hits assert(is_dominator(c, n_ctrl)) failed
• 3269cec: 8286870: Memory leak with RepeatCompilation
• 47e478d: 8279622: C2: miscompilation of map pattern as a vector reduction
• d90fd6f: 8282937: Write a regression test for JDK-4820080
• 270a474: 8211002: test/jdk/java/lang/Math/PowTests.java skips testing for non-corner-case values
• 6f0f842: 8286582: Build fails on macos aarch64 when using --with-zlib=bundled
• 68456bb: 8288754: GCC 12 fails to build zReferenceProcessor.cpp
• 72603ff: 8288303: C1: Miscompilation due to broken Class.getModifiers intrinsic
• a2be28d: 8283457: [macos] libpng build failures with Xcode13.3
• a411085: 8285081: Improve XPath operators count accuracy
• ... and 12 more: https://git.openjdk.org/jdk17u-dev/compare/50c0080689d7971162669d72cf5e21cfd3bc2321...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.

[GoeLin]

/integrate

[openjdk]

Going to push as commit caceaba.
Since your change was applied there have been 22 commits pushed to the master branch:

• dd7ab3d: 8280696: C2 compilation hits assert(is_dominator(c, n_ctrl)) failed
• 3269cec: 8286870: Memory leak with RepeatCompilation
• 47e478d: 8279622: C2: miscompilation of map pattern as a vector reduction
• d90fd6f: 8282937: Write a regression test for JDK-4820080
• 270a474: 8211002: test/jdk/java/lang/Math/PowTests.java skips testing for non-corner-case values
• 6f0f842: 8286582: Build fails on macos aarch64 when using --with-zlib=bundled
• 68456bb: 8288754: GCC 12 fails to build zReferenceProcessor.cpp
• 72603ff: 8288303: C1: Miscompilation due to broken Class.getModifiers intrinsic
• a2be28d: 8283457: [macos] libpng build failures with Xcode13.3
• a411085: 8285081: Improve XPath operators count accuracy
• ... and 12 more: https://git.openjdk.org/jdk17u-dev/compare/50c0080689d7971162669d72cf5e21cfd3bc2321...master

Your commit was automatically rebased without conflicts.

[openjdk]

@GoeLin Pushed as commit caceaba.

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