8337780: RISC-V: C2: Change C calling convention for sp to NS

[RealFYang]

Clean backport of JDK-8337780 to reduce frame size by 16 bytes and improve performance for some C2 runtime stubs as we do not have to save sp on the method entry. Gtest & Tier1-3 tested on linux-riscv64 platform.

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8337780 needs maintainer approval

Issue

• JDK-8337780: RISC-V: C2: Change C calling convention for sp to NS (Enhancement - P4 - Approved)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk23u.git pull/87/head:pull/87
$ git checkout pull/87

Update a local copy of the PR:
$ git checkout pull/87
$ git pull https://git.openjdk.org/jdk23u.git pull/87/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 87

View PR using the GUI difftool:
$ git pr show -t 87

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk23u/pull/87.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back fyang! 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]

@RealFYang 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:

8337780: RISC-V: C2: Change C calling convention for sp to NS

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[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

⚠️ @RealFYang 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.

[RealFYang]

/approval request Clean backport of JDK-8337780 to reduce frame size by 16 bytes and improve performance for some C2 runtime stubs as we do not have to save sp on the method entry. This is a RISC-V specific change. Tier1-3 tested on linux-riscv64 platform.

[openjdk]

@RealFYang
8337780: The approval request has been created successfully.

[mlbridge]

Webrevs

• 00: Full (c8291a9b)

[RealFYang]

/integrate

[openjdk]

Going to push as commit 7bdece3.

[openjdk]

@RealFYang Pushed as commit 7bdece3.

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