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

[Magnus Ihse Bursie]

On Wed, 8 May 2024 13:30:59 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.

When making a build comparison, the build result was identical on Windows (of course), and macOS. On linux/x64 and linux/aarch64, there was a slight difference, in that a few functions did not properly set `.type`, so they appeared as `NOTYPE` instead of `FUNC` in the symbol table.

I have not done comparison builds for other linux platforms, but I assume that GHA passing is good enough.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/19138#issuecomment-2100776636