On Mon, 3 Apr 2023 07:17:59 GMT, David Holmes <dhol...@openjdk.org> wrote:
> We have the strange situation where calling `t.isAlive()` on a
> `java.lang.Thread` `t`, will call into the VM (via `alive()` then
> `isAlive0()`) where the VM then examines the `eetop` field of `t` to extract
> its `JavaThread` pointer and compare it to null. We can simply read `eetop`
> directly in `Thread.alive()`:
>
> boolean alive() {
> return eetop != 0;
> }
>
> I also updated a comment in relation to `eetop`.
>
> Testing: tiers 1-3
>
> Thanks
src/java.base/share/classes/java/lang/Thread.java line 231:
> 229: /* Reserved for exclusive use by the JVM. Cannot be moved to
> FieldHolder
> 230: as it needs to be set by the VM before executing the constructor
> that
> 231: will set FieldHolder.
"will set FieldHolder" is a bit confusing. It creates the FieldHolder and sets
the field "holder" so I think the comment could be a bit clearer.
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PR Review Comment: https://git.openjdk.org/jdk/pull/13287#discussion_r1155601934
