RFR: 8255617: Zero: purge the remaining bytecode interpreter profiling support

[Coleen Phillimore]

On Thu, 29 Oct 2020 19:47:02 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> All the stubs in `interpreter/zero/bytecodeInterpreterProfiling.hpp` are empty. History shows the whole thing gradually moved to template interpreter. We can probably simplify Zero code by dropping these empty stubs altogether. Arguably, this makes porting to new architectures a bit harder, but it seems that the proper stepping stone after Zero is implementing template interpreter anyway.
> 
> On my TR 3970X, this improves:
>  - Linux x86_64 Zero "make images" times from ~18 minutes to ~17.5 minutes
> 
> I would like to have the opinion of @GoeLin who added this for PPC64 porting back in 8u. And probably @DamonFool who is usually interested in Zero. And @jerboaa, @gnu-andrew who deal with Zero from time to time.

I left this code from the C++ interpreter because I had a dream that we could someday hook zero up to c1/c2 someday, but if so, there would be a more work than adding these back.  I'd be interested to see what these other people with interest in Zero think.  But this LGTM.

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Marked as reviewed by coleenp (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/944