RFR: 8331921: Hotspot assembler files should use common logic to setup exported functions [v2]

[David Holmes]

On Thu, 23 May 2024 16:33:14 GMT, Magnus Ihse Bursie <ihse at openjdk.org> wrote:

>> As seen in [JDK-8331541](https://bugs.openjdk.org/browse/JDK-8331541), if we are not consistently setting all assembler directives correctly, we can get errors that are not detected by the linker.
>> 
>> We should stop duplicating this code and create a unified macro to properly setup functions, and use it everywhere.
>
> Magnus Ihse Bursie has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains five commits:
> 
>  - Merge branch 'master' into hotspot-assembler-functions
>  - Fix copyright headers
>  - Fix building on macos/aarch64
>  - Use % instead of @ due to arm assembler
>  - 8331921: Hotspot assembler files should use common logic to setup exported functions

What testing has been done in our CI?

The changes seem quite reasonable but it would be easy to overlook a small difference, so the proof of this is in the building and testing.

One query below, but hitting approve.

Thanks

make/hotspot/lib/CompileJvm.gmk line 53:

> 51:         -I$(TOPDIR)/src/hotspot/os_cpu/$(HOTSPOT_TARGET_OS)_$(HOTSPOT_TARGET_CPU_ARCH) \
> 52:         -I$(TOPDIR)/src/hotspot/os/$(HOTSPOT_TARGET_OS) \
> 53:         -I$(TOPDIR)/src/hotspot/os/$(HOTSPOT_TARGET_OS_TYPE) \

What does the second line evaluate to on Windows? Does it duplicate the prior line?

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Marked as reviewed by dholmes (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/19138#pullrequestreview-2081640019
PR Review Comment: https://git.openjdk.org/jdk/pull/19138#discussion_r1616510889