8293976: Use unsigned integers in Assembler/CodeBuffer::emit_int*

[merykitty]

Assembler/CodeBuffer::emit_int* accept signed int arguments.

• Since we are trying to emit some bit patterns into the code buffer instead of doing integer arithmetics, it makes more sense to use unsigned parameters.

• It makes usage with constants become inconvenient, as an integer literal is positive, a 0xC0 does not fit into an int8_t, resulting in the compiler complaining about lossy implicit conversions, the current solution is manual casting of the constants to unsigned char, which can be converted to int8_t without complaints.

Please have a look and leave some reviews. Thanks very much.

---

Progress

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Issue

• JDK-8293976: Use unsigned integers in Assembler/CodeBuffer::emit_int*

Reviewers

• Vladimir Kozlov (@vnkozlov - Reviewer)
• Jatin Bhateja (@jatin-bhateja - Reviewer)

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (c03023e6)

[jatin-bhateja]

Do you also plan to cleanup redundant char casting usages from assembler after your modifications.

[merykitty]

@jatin-bhateja Thanks for taking a look, those redundant casts do not have any drawbacks so I think existing usages could stay as they are.

[vnkozlov]

Good. I will test it.

[vnkozlov]

Testing passed.

[openjdk]

@merykitty 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:

8293976: Use unsigned integers in Assembler/CodeBuffer::emit_int*

Reviewed-by: kvn, jbhateja

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 25 new commits pushed to the master branch:

• fe541f0: 8293989: [JVMCI] re-use cleared oop handles
• 0fa7d9e: 8278863: Add method ClassDesc::ofInternalName
• 4020ed5: 8293210: G1: Remove redundant check in G1FreeHumongousRegionClosure
• 8ff2c26: 8293942: [JVMCI] data section entries must be 4-byte aligned on AArch64
• 6e23b43: 8293502: (fc) FileChannel::transfer methods fail to copy /proc files on Linux
• 1f9ff41: 8292297: Fix up loading of override java.security properties file
• 64b96e5: 8293811: Provide a reason for PassFailJFrame.forceFail
• f91762f: 8293965: Code signing warnings after JDK-8293550
• 8082c24: 8054572: [macosx] JComboBox paints the border incorrectly
• b920d29: 8271328: User is able to choose the color after disabling the color chooser.
• ... and 15 more: https://git.openjdk.org/jdk/compare/cfd44bb2cd4f2fdbfc15a7a76757a92c0a557439...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.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change. Possible candidates are the reviewers of this PR (@vnkozlov, @jatin-bhateja) but any other Committer may sponsor as well.

➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[jatin-bhateja]

@jatin-bhateja Thanks for taking a look, those redundant casts do not have any drawbacks so I think existing usages could stay as they are.

Fine.

[jatin-bhateja]

@jatin-bhateja Thanks for taking a look, those redundant casts do not have any drawbacks so I think existing usages could stay as they are.

Fine.

Only drawback is that someone may still accidently add more casts on finding some occurrences of redundant casts in that file. So ideally you can remove redundancies with your new code changes.

[merykitty]

Thanks a lot for your reviews.
@jatin-bhateja In that case I will follow up with a patch that does some cleanup in the assembler, including removing of these casts.
/integrate

[openjdk]

@merykitty
Your change (at version c03023e) is now ready to be sponsored by a Committer.

[DamonFool]

/sponsor

[openjdk]

Going to push as commit a07902b.
Since your change was applied there have been 25 commits pushed to the master branch:

• fe541f0: 8293989: [JVMCI] re-use cleared oop handles
• 0fa7d9e: 8278863: Add method ClassDesc::ofInternalName
• 4020ed5: 8293210: G1: Remove redundant check in G1FreeHumongousRegionClosure
• 8ff2c26: 8293942: [JVMCI] data section entries must be 4-byte aligned on AArch64
• 6e23b43: 8293502: (fc) FileChannel::transfer methods fail to copy /proc files on Linux
• 1f9ff41: 8292297: Fix up loading of override java.security properties file
• 64b96e5: 8293811: Provide a reason for PassFailJFrame.forceFail
• f91762f: 8293965: Code signing warnings after JDK-8293550
• 8082c24: 8054572: [macosx] JComboBox paints the border incorrectly
• b920d29: 8271328: User is able to choose the color after disabling the color chooser.
• ... and 15 more: https://git.openjdk.org/jdk/compare/cfd44bb2cd4f2fdbfc15a7a76757a92c0a557439...master

Your commit was automatically rebased without conflicts.

[openjdk]

@DamonFool @merykitty Pushed as commit a07902b.

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