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

[Axel Boldt-Christmas]

On Thu, 23 Oct 2025 15:44:39 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.

Sounds resonable.

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Marked as reviewed by aboldtch (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/27956#pullrequestreview-3374738933