RFR: 8272586: emit abstract machine code in hs-err logs [v4]

[Doug Simon]

On Thu, 7 Oct 2021 20:27:34 GMT, Doug Simon <dnsimon at openjdk.org> wrote:

>> This enhances hs-err logs to:
>> * Show the [abstract machine code](https://bugs.openjdk.java.net/browse/JDK-8213084) of the crashing frame if a disassembler is not installed.
>> * Show machine code for the top frames on the native stack.
>> 
>> An interpreter or stub frame is only shown if it is the crashing frame.
>> 
>> A sample of the enhanced hs-err log can be seen [here](https://bugs.openjdk.java.net/secure/attachment/96664/hs_err_pid7179.log).
>
> Doug Simon has updated the pull request incrementally with one additional commit since the last revision:
> 
>   disable write protection before decoding nmethod

Thanks, you're right. I placed it in `nmethod::decode2`: 62cc866440084366dc4b69d47391557a9457f6bd

BTW, I noticed that often nmethod info is written to `tty` during crash reporting. I tracked this down to [this change](https://github.com/dougxc/jdk/commit/4af237427144060d0b97c14a086401b0a3781198#diff-82948e0048fb88e1e9281b61394d9a9e2e0c8e75ab1a834c3bf943dbde73e2ffR618) where the `st` argument is ignored. @TheRealMDoerr do you think that should be fixed?

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PR: https://git.openjdk.java.net/jdk/pull/5446