8293337: Store method handle intrinsics in AOT cache

[iklam]

This is the 5th PR for JEP 483: Ahead-of-Time Class Loading & Linking.

This PR is necessary to support JDK-8293336: AOT-linking of invokedynamic for lambda expression and string concat, which needs to store Java heap objects that have native pointers to the C++ Method objects returned by SystemDictionary::find_method_handle_intrinsic()

These Method objects are created within the JVM. They do not belong to any actual Java classes. We store all these Method objects into the AOT cache, so that they can be referenced by other artifacts in the AOT cache.

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See here for the sequence of dependent RFEs for implementing JEP 483.

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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

Integration blockers

 ⚠️ Dependency #20958 must be integrated first
 ⚠️ Title mismatch between PR and JBS for issue JDK-8293337

Issue

• JDK-8293337: Store method handle intrinsics in AOTCache (Enhancement - P4) ⚠️ Title mismatch between PR and JBS.

Reviewers

• Vladimir Kozlov (@vnkozlov - Reviewer) 🔄 Re-review required (review applies to 988f101c)
• Coleen Phillimore (@coleenp - Reviewer) 🔄 Re-review required (review applies to 1e79b7e2)
• Ashutosh Mehra (@ashu-mehra - Committer) 🔄 Re-review required (review applies to a9356279)
• Vladimir Ivanov (@iwanowww - Reviewer) 🔄 Re-review required (review applies to a9356279)
• Andrew Dinn (@adinn - Reviewer) 🔄 Re-review required (review applies to a9356279)
• John R Rose (@rose00 - Reviewer) 🔄 Re-review required (review applies to 1e79b7e2)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/20959/head:pull/20959
$ git checkout pull/20959

Update a local copy of the PR:
$ git checkout pull/20959
$ git pull https://git.openjdk.org/jdk.git pull/20959/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 20959

View PR using the GUI difftool:
$ git pr show -t 20959

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/20959.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back iklam! A progress list of the required criteria for merging this PR into pr/20958 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 change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

@iklam The following label will be automatically applied to this pull request:

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[mlbridge]

Webrevs

• 11: Full - Incremental (27337ead)
• 10: Full - Incremental (1e79b7e2)
• 09: Full - Incremental (a9356279)
• 08: Full - Incremental (84777aa4)
• 07: Full - Incremental (9b787423)
• 06: Full - Incremental (180375ac)
• 05: Full - Incremental (59dd8879)
• 04: Full - Incremental (66157452)
• 03: Full - Incremental (988f101c)
• 02: Full - Incremental (16b51d55)
• 01: Full - Incremental (a57e9f00)
• 00: Full (9385da0c)

[vnkozlov]

Looks good to me. But I am not expert in this code.

[openjdk]

⚠️ @iklam 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).

[coleenp]

I have one question, but this is good. I've always wanted these to be shared.

[coleenp]

Can you add // INCLUDE_CDS

This is called at startup time before anything so it doesn't need the locking?

[iklam]

I added the INCLUDE_CDS. I also added locking (or assert safepoint). They are probably not needed now, but will make the code safer in case someone tries to move or refactor it.

[ashu-mehra]

lgtm!

[iwanowww]

Looks good.

[adinn]

This all looks good.

[coleenp]

I forgot to release my comment. You could hold the lock for the duration if you want.

[coleenp]

This looks good. I've always wondered if CDS could share these.

[rose00]

Good changes. One request: Please add a comment, if there isn't one somewhere already, saying (as an order of magnitude) what is a typical size of the MH intrinsic table. That would be an estimate of the number printed by this log message:

  log_info(cds)("Archived %d method handle intrinsics", len)

[iklam]

Closing this PR as its changes have been combined into #21642.

[iklam]

Good changes. One request: Please add a comment, if there isn't one somewhere already, saying (as an order of magnitude) what is a typical size of the MH intrinsic table. That would be an estimate of the number printed by this log message:

  log_info(cds)("Archived %d method handle intrinsics", len)

I have added size statistics in the combined PR

https://github.com/openjdk/jdk/pull/21642/files#diff-ca37be6e6608d8db9e461dffd6574bc8a2dc3d1e0e88d9ba66735d4b37f8c226R377-R390

It looks like this:

[0.603s][info][cds] Archived 19 method handle intrinsics (5784 bytes)     <-- for HelloWorld
[1.696s][info][cds] Archived 61 method handle intrinsics (18552 bytes)    <-- for 'javac HelloWorld.java'