Withdrawn: 8356027: Print enhanced compilation timings

[duke]

On Thu, 1 May 2025 12:35:38 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> In Leyden, we have the extended compilation timings printouts with -XX:+PrintCompilation / UL, that are very useful to study compiler dynamics. These timings include:
>  1. Time spent before queuing: shows the compilation queue bottlenecks
>  2. Time spent in the queue: shows delays caused by queue bottlenecks and compiler load
>  3. Time spent actually compiling: shows the per-method compilation costs
> 
> We should consider the same kind of printout for mainline. This would also require us to print the compilation task _after_ the compilation, not only before it. This improvement would also obviate any need for `PrintCompilation2` flag, [JDK-8356028](https://bugs.openjdk.org/browse/JDK-8356028).
> 
> The difference from the output format we ship in Leyden:
>  1. This output prints before/after the compilation to maintain old behavior partially. The "before" printout is now prepended with `started` to clearly mark it as such.
>  2. The output is raw number in microseconds. In Leyden repo, we have these prepended with characters, like `C0.1`, but that prepending makes it a bit inconvenient with scripts. This PR also does microseconds, instead of fractional milliseconds. This should be enough to capture the wide range of durations.
> 
> See the sample `-XX:+PrintCompilation` output in the comments.
> 
> Additional testing:
>  - [x] Linux x86_64 server fastdebug, `compiler`
>  - [x]  Linux x86_64 server fastdebug, `all`

This pull request has been closed without being integrated.

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

PR: https://git.openjdk.org/jdk/pull/24984