RFR: 8370500: Change windows x64 implementation of os::current_stack_pointer() [v2]

[Andrew Dinn]

On Mon, 27 Oct 2025 08:53:44 GMT, Erik Österlund <eosterlund at openjdk.org> wrote:

>> The current implementation of os::current_stack_pointer() on windows x64 uses a code stub to read the stack pointer. This means that os::current_stack_pointer() may not be called early on in the bootstrapping. This prevents unhandled oops from being enabled early on.
>> 
>> However, there is an MSVC intrinsic that provides the same functionality without the need to use stubs: _AddressOfReturnAddress() from intrin.h
>> By changing this implementation on windows x64, we should be able to call os::current_stack_pointer() early on as it is seemingly the only implementation with such a bootstrapping dependency.
>
> Erik Österlund has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Comment

Looks good to me.

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Marked as reviewed by adinn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/27956#pullrequestreview-3387434760