[foreign-memaccess+abi] RFR: 8255902: Enable stack arguments for native invokers & optimized upcall stubs [v2]

[Jorn Vernee]

> Hi,
> 
> This patch implements stack argument support in native invokers & optimized upcalls stubs.
> 
> The main changes needed are:
> - allow passing a stack offset 'bias' to shuffling code in macro assembler, so that it can account for shadow space (only needed on x86_64 for now).
> - implement missing stack to reg & reg to stack moves for float and double on AArch64
> - add TestDowncallStack & TestUpcallStack, which are basically the same as TestDowncall & TestUpcall, but with 8 `long long` and 8 `double` prefix arguments which saturate the argument registers and makes the arguments that are being tested passed on the stack instead.
> 
> Thanks,
> Jorn

Jorn Vernee has updated the pull request incrementally with one additional commit since the last revision:

  Fold TestDown/UpcallStack into TestDown/Upcall to reduce code duplication

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

Changes:
  - all: https://git.openjdk.java.net/panama-foreign/pull/600/files
  - new: https://git.openjdk.java.net/panama-foreign/pull/600/files/194c942c..ff1f45cb

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=panama-foreign&pr=600&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=panama-foreign&pr=600&range=00-01

  Stats: 458 lines in 5 files changed: 95 ins; 330 del; 33 mod
  Patch: https://git.openjdk.java.net/panama-foreign/pull/600.diff
  Fetch: git fetch https://git.openjdk.java.net/panama-foreign pull/600/head:pull/600

PR: https://git.openjdk.java.net/panama-foreign/pull/600