[release/8.0] [NativeAOT] Switch macOS to mmap thunks like iOS platforms

[github-actions]

Backport of #91751 to release/8.0

/cc @jkotas @filipnavara

Customer Impact

Apps published as native AOT do not work with hardened runtime on macOS. It is regression relative to regular CoreCLR w/ JIT that prevents native AOT compiled apps from being published on the app store.

Testing

Ad hoc testing.

Risk

Medium. The change itself is small, but it enables hundreds of lines of low-level code. that have been used for iOS.

IMPORTANT: If this backport is for a servicing release, please verify that:

• The PR target branch is release/X.0-staging, not release/X.0.

• If the change touches code that ships in a NuGet package, you have added the necessary package authoring and gotten it explicitly reviewed.

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Issue Details

---

Backport of #91751 to release/8.0

/cc @jkotas @filipnavara

Customer Impact

Testing

Risk

IMPORTANT: If this backport is for a servicing release, please verify that:

• The PR target branch is release/X.0-staging, not release/X.0.

• If the change touches code that ships in a NuGet package, you have added the necessary package authoring and gotten it explicitly reviewed.

Author:	github-actions[bot]
Assignees:	-
Labels:	area-NativeAOT-coreclr
Milestone:	-

[jeffschwMSFT]

approved. this can be merged when ready

[carlossanlop]

@filipnavara @jkotas there is a NativeAOT failure in osx-x64. Is it related to this change? https://github.com/dotnet/runtime/pull/92136/checks?check_run_id=16837406532

[agocke]

Looks like this change very slightly increases the size of the executable. I assume that's expected? Because we now have to reserve a page for the thunks?

[jkotas]

Yes, it is expected. We have not seen this issue in main because of it has other size reducing changes.