JDK-8310020: MacroAssembler::call_VM(_leaf) doesn't consistently check for conflict with C calling convention.

[dafedafe]

Issue

The MacroAssembler::call_VM and MacroAssembler::call_VM_leaf methods don't include asserts to check if the passed arguments collide with the C calling convention registers consistently. Some versions omit them completely (e.g. aarch64 MacroAssembler::call_VM_leaf), other ones use regular asserts (where the assert_different_registers function should be used).

Solution

We use assert_different_registers across all MacroAssembler::call_VM and MacroAssembler::call_VM_leaf where a check is needed (except for the arm implementation, which doesn't change as it uses fixed registers).

Testing

This fix includes changes for x86_32/64 and aarch64, which I could test thoroughly but also for ppc, riscv, and s390 for which I would need some help with testing.

---

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-8310020: MacroAssembler::call_VM(_leaf) doesn't consistently check for conflict with C calling convention. (Enhancement - P4)

Reviewers

• Tobias Hartmann (@TobiHartmann - Reviewer) ⚠️ Review applies to 841f0181
• Fei Yang (@RealFYang - Reviewer)
• Martin Doerr (@TheRealMDoerr - Reviewer)
• Amit Kumar (@offamitkumar - Committer)

Reviewing

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Update a local copy of the PR:
$ git checkout pull/14470
$ git pull https://git.openjdk.org/jdk.git pull/14470/head

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$ git pr checkout 14470

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https://git.openjdk.org/jdk/pull/14470.diff

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[bridgekeeper]

👋 Welcome back dafedafe! 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]

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

• hotspot

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[mlbridge]

Webrevs

• 02: Full - Incremental (a7a1abd1)
• 01: Full - Incremental (841f0181)
• 00: Full (a9dea0c5)

[TobiHartmann]

Looks good to me.

[openjdk]

@dafedafe 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:

8310020: MacroAssembler::call_VM(_leaf) doesn't consistently check for conflict with C calling convention.

Reviewed-by: thartmann, fyang, mdoerr, amitkumar

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 64 new commits pushed to the master branch:

• 79069c5: 8310314: Misplaced "unnamed classes are a preview feature and are disabled by default" error
• 96a7db7: 8309228: Clarify EXPERIMENTAL flags comment in hotspot/share/runtime/globals.hpp
• b2e86ae: 8304478: Initial nroff manpage generation for JDK 22
• 7b45c8f: 8241800: Disable IPV6_MULTICAST_ALL to prevent interference from all multicast groups
• 137a5f7: 8310105: LoongArch64 builds are broken after JDK-8304913
• 33c6ec9: 8310019: MIPS builds are broken after JDK-8304913
• e08e94f: 8310266: JFR: Refactor after 'view' command
• f8f8bfb: 8309939: HttpClient should not use Instant.now() as Instant source for deadlines
• 7d4b77a: 8304835: jdk/jfr/event/oldobject/TestArrayInformation.java fails with "Could not find event with class ... as (leak) object"
• b896e3e: 8310146: Removing unused PerfLongVariant::_sampled
• ... and 54 more: https://git.openjdk.org/jdk/compare/4c18b9e1faba32bd54a5d8b0b3c21b07f694c71b...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 (@TobiHartmann, @RealFYang, @TheRealMDoerr, @offamitkumar) 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).

[RealFYang]

Hello, I can help do some tests on linux-riscv64 platform.
But I think we need following extra changes for riscv. Could you please help add this? Thanks.

diff --git a/src/hotspot/cpu/riscv/macroAssembler_riscv.cpp b/src/hotspot/cpu/riscv/macroAssembler_riscv.cpp
index e6d1e66e0c0..32a144b2d42 100644
--- a/src/hotspot/cpu/riscv/macroAssembler_riscv.cpp
+++ b/src/hotspot/cpu/riscv/macroAssembler_riscv.cpp
@@ -666,6 +666,7 @@ void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0) {
 }

 void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0, Register arg_1) {
+  assert_different_registers(arg_1, c_rarg0);
   pass_arg0(this, arg_0);
   pass_arg1(this, arg_1);
   call_VM_leaf_base(entry_point, 2);
@@ -673,6 +674,8 @@ void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0, Register

 void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0,
                                   Register arg_1, Register arg_2) {
+  assert_different_registers(arg_1, c_rarg0);
+  assert_different_registers(arg_2, c_rarg0, c_rarg1);
   pass_arg0(this, arg_0);
   pass_arg1(this, arg_1);
   pass_arg2(this, arg_2);

[dafedafe]

Thanks @RealFYang, I missed it! It should be fixed now.
Thanks for testing too!

[RealFYang]

Updated change LGTM. I can do native fastdebug build with this and run non-trivial benchmark workloads on linux-riscv64 platform. Thanks.

[dafedafe]

This PR includes changes for ppc and s390 that I couldn't test either.
@TheRealMDoerr, @offamitkumar could I ask you if you could please run some tests on this change as well for ppc/s390 (and possibly also have a quick look at it)? Thank you very much!

[TheRealMDoerr]

Thanks for cleaning this up! PPC64 part is good.

[offamitkumar]

LGTM, Test result also came clean. A few other assert-occurrence could be updated but I guess those are out of scope for this PR.

Thank you very much for the change :-)

[dafedafe]

@TobiHartmann @offamitkumar @TheRealMDoerr @RealFYang thank you very much for your reviews!

[dafedafe]

/integrate

[openjdk]

@dafedafe
Your change (at version a7a1abd) is now ready to be sponsored by a Committer.

[offamitkumar]

/sponsor

[openjdk]

Going to push as commit 0878872.
Since your change was applied there have been 64 commits pushed to the master branch:

• 79069c5: 8310314: Misplaced "unnamed classes are a preview feature and are disabled by default" error
• 96a7db7: 8309228: Clarify EXPERIMENTAL flags comment in hotspot/share/runtime/globals.hpp
• b2e86ae: 8304478: Initial nroff manpage generation for JDK 22
• 7b45c8f: 8241800: Disable IPV6_MULTICAST_ALL to prevent interference from all multicast groups
• 137a5f7: 8310105: LoongArch64 builds are broken after JDK-8304913
• 33c6ec9: 8310019: MIPS builds are broken after JDK-8304913
• e08e94f: 8310266: JFR: Refactor after 'view' command
• f8f8bfb: 8309939: HttpClient should not use Instant.now() as Instant source for deadlines
• 7d4b77a: 8304835: jdk/jfr/event/oldobject/TestArrayInformation.java fails with "Could not find event with class ... as (leak) object"
• b896e3e: 8310146: Removing unused PerfLongVariant::_sampled
• ... and 54 more: https://git.openjdk.org/jdk/compare/4c18b9e1faba32bd54a5d8b0b3c21b07f694c71b...master

Your commit was automatically rebased without conflicts.

[openjdk]

@offamitkumar @dafedafe Pushed as commit 0878872.

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