RFR: 8252505: C1/C2 compiler support for blackholes [v23]

[Aleksey Shipilev]

On Fri, 4 Dec 2020 09:50:58 GMT, Vladimir Ivanov <vlivanov at openjdk.org> wrote:

>> Then check `PrintWarnings`? It's an explicit user request to silent JVM warnings on output stream.
>
> I agree now that `CompileCommand=quiet` is not appropriate here.

All right. I see `CompilerOracle` sometimes calls into `warning` from `debug.cpp` that handles `PrintWarnings`. Updated new hunk to use it, and a test case that proves it works.

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PR: https://git.openjdk.java.net/jdk/pull/1203