8241503: C2: Share MacroAssembler between mach nodes during code emission

[JohnTortugo]

Hi there, can I please get some reviews on this change? The patch is to make the code reuse the same C2_MacroAssembler object during the emission of CPU instructions of a given compilation.

As you'll see the change affects all backends. I've done my best to keep the changes minimal/simple.

I tested this locally on Linux x86_64, x86_32 and MacOS Arm32, and ARM64.

I need help testing the changes on PPC, S390, and RISCV. I cross-compiled the JVM locally and the builds are all succeeding, but I couldn't use an emulator (yet) or any real hardware (no access to one) to test the changes on these platforms. I see that GitHub actions do some tests on S390 and PPC but the tests seem to not be extensive.

Thanks in advance,
Cesar

---

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

Issue

• JDK-8241503: C2: Share MacroAssembler between mach nodes during code emission

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk pull/9074/head:pull/9074
$ git checkout pull/9074

Update a local copy of the PR:
$ git checkout pull/9074
$ git pull https://git.openjdk.org/jdk pull/9074/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 9074

View PR using the GUI difftool:
$ git pr show -t 9074

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/9074.diff

[bridgekeeper]

👋 Welcome back JohnTortugo! 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]

@JohnTortugo this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout 8241503-share-asm
git fetch https://git.openjdk.java.net/jdk master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
git push

[openjdk]

⚠️ @JohnTortugo This pull request contains merges that bring in commits not present in the target repository. Since this is not a "merge style" pull request, these changes will be squashed when this pull request in integrated. If this is your intention, then please ignore this message. If you want to preserve the commit structure, you must change the title of this pull request to Merge <project>:<branch> where <project> is the name of another project in the OpenJDK organization (for example Merge jdk:master).

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[mlbridge]

Webrevs

• 03: Full - Incremental (8ebb3dca)
• 02: Full (fbb8cb1c)
• 01: Full - Incremental (13fe3060)
• 00: Full (7c739f77)

[vnkozlov]

Nice work. I think we can target this for JDK 20. Please, update it to latest JDK - there are conflicts.

[JohnTortugo]

Hi again, can someone with access to a PPC64, S360, etc. help with testing this?

[bridgekeeper]

@JohnTortugo This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[JohnTortugo]

I'll resolve the conflicts and continue working on this. Any help testing will be appreciated.

[bridgekeeper]

@JohnTortugo This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[bridgekeeper]

@JohnTortugo This pull request has been inactive for more than 8 weeks and will now be automatically closed. If you would like to continue working on this pull request in the future, feel free to reopen it! This can be done using the /open pull request command.