RFR: 8296477: Foreign linker implementation update following JEP 434

[Robbin Ehn]

On Mon, 7 Nov 2022 14:34:45 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

> Pull in linker implementation changes, that include non-trivial changes to VM code, from the panama-foreign repo into the main JDK.
> 
> This is split off from the main JEP integration to make reviewing easier.
> 
> This includes the following patches:
> 
> 1. https://github.com/openjdk/panama-foreign/pull/698
> 2. https://github.com/openjdk/panama-foreign/pull/699
> 3. (part of) https://github.com/openjdk/panama-foreign/pull/731
> 4. https://github.com/openjdk/panama-foreign/pull/740
> 5. https://github.com/openjdk/panama-foreign/pull/746
> 6. https://github.com/openjdk/panama-foreign/pull/742
> 7. https://github.com/openjdk/panama-foreign/pull/743
> 
> Probably the biggest change to the code comes from replacing `VMReg` - which can not represent offsets into the stack that are not a multiple of the VM's stack slot size (32-bits) - with the new `VMStorage` class, which can describe byte offsets into the stack, as well as having a register mask to indicate only certain register segments.
> 
> The only part of 3. that is in this PR is the part that turns the `VMStorage` class in Java into a record.
> 
> Please refer to the PR of each individual patch for a more detailed description.

Looks good (-+ few nits), the errno capture feature seems handy, thanks!

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

Marked as reviewed by rehn (Reviewer).

PR: https://git.openjdk.org/jdk/pull/11019