RFR: 8351149: Remove dead IA32/X32/!AMD64 code blocks after 32-bit x86 removal

[Stefan Karlsson]

On Sun, 26 Oct 2025 09:18:40 GMT, Anton Seoane Ampudia <aseoane at openjdk.org> wrote:

> This PR carries out cleanup of `IA32`-, `X32`- and `!AMD64`-guarded code blocks after the removal of the 32-bit x86 architecture from HotSpot.
> 
> These code blocks are either not needed anymore or the guards redundant.
> 
> Please note that this changeset addresses the "complement" of [JDK-8351159](https://github.com/openjdk/jdk/pull/27987). This is to say, this PR targets all directories that are *not* `cpu/x86` and `os_cpu/x86`.
> 
> **Testing:** passes tiers 1-3

Changes requested by stefank (Reviewer).

src/hotspot/os/linux/os_linux.cpp line 3097:

> 3095:   vgetcpu_t vgetcpu = (vgetcpu_t)VSYSCALL_ADDR(__NR_vgetcpu);
> 3096:   retval = vgetcpu(&cpu, nullptr, nullptr);
> 3097: #endif

Should this really have been removed?

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

PR Review: https://git.openjdk.org/jdk/pull/27990#pullrequestreview-3382481257
PR Review Comment: https://git.openjdk.org/jdk/pull/27990#discussion_r2464928052