RFR: 8357434: x86: Simplify Interpreter::profile_taken_branch [v3]

[Vladimir Kozlov]

On Tue, 3 Jun 2025 09:38:09 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> Noticed that `Interpreter::profile_taken_branch` has the same `sbbptr` pattern we have eliminated with [JDK-8356946](https://bugs.openjdk.org/browse/JDK-8356946). The same logic applies here: the counter is 64-bit, never practically overflows, and no other code cares about it.
>> 
>> Also tidied up some comments around it.
>> 
>> Additional testing;
>>  - [x] Linux x86_64 server fastdebug, `tier1 tier2`
>>  - [x] Linux x86_64 server fastdebug, `all`
>
> Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:
> 
>  - Merge branch 'master' into JDK-8357434-x86-profile-taken
>  - Stale comment
>  - Merge branch 'master' into JDK-8357434-x86-profile-taken
>  - Fix

Re-approved.

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Marked as reviewed by kvn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/25343#pullrequestreview-2893267613