RFR: 8254793: [JVMCI] improve speculation encoding [v4]

[Doug Simon]

On Fri, 16 Oct 2020 19:45:51 GMT, Dean Long <dlong at openjdk.org> wrote:

>> Doug Simon has refreshed the contents of this pull request, and previous commits have been removed. The incremental
>> views will show differences compared to the previous content of the PR. The pull request contains one new commit since
>> the last revision:
>>   8254793: encode a HotSpotSpeculation in 31 bits
>
> Marked as reviewed by dlong (Reviewer).

@dean-long @vnkozlov I've made a few new changes based on @tkrodriguez 's comments. Please let me know if it still
looks good. I've also rerun mach5 testing on the new changes and everything passes.

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PR: https://git.openjdk.java.net/jdk/pull/667