RFR: 8332670: C1 clone intrinsic needs memory barriers [v2]

[Galder Zamarreño]

> Adds a storestore barrier after copying the contents in the primitive array intrinsic (credit @shipilev). The barrier is a no-op in platforms where not needed so no need for an ifdef.
> 
> The barrier after new array creation is only added if zeroing the array on aarch64 (credit @dean-long). Since the primitive array clone intrinsic does not zero the array, that means there's a single barrier added for this use case.
> 
> There's no barrier added on x86 c1 macro assembler for nothing to do there. 
> 
> I've run the following tests:
> * tier 1 on darwin/aarch64
> * tier 1 on linux/x86_64
> * `hotspot_compiler` tests on darwin/aarch64
> * `copy.clone.arrays` jcstress tests on darwin/aarch64.
> 
> I tried but was unable to create a standalone test for the jdk source tree that would fail.
> 
> FYI @bulasevich @TheRealMDoerr @RealFYang @RealLucy similar platform specific c1 macro assembler changes might be required for other platforms.

Galder Zamarreño has updated the pull request incrementally with one additional commit since the last revision:

  Keep storestore barrier for array allocation
  
  * Having c1 array clone use 2 storestore barriers
  has no performance impact, so it's safer to keep it in place.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/19538/files
  - new: https://git.openjdk.org/jdk/pull/19538/files/6400b755..24d72c67

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19538&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19538&range=00-01

  Stats: 6 lines in 1 file changed: 0 ins; 5 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/19538.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19538/head:pull/19538

PR: https://git.openjdk.org/jdk/pull/19538