RFR: 8285394: Compiler blackholes can be eliminated due to stale ciMethod::intrinsic_id() [v2]

[Vladimir Kozlov]

On Thu, 21 Apr 2022 17:14:03 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> This is seen in some tests: if blackhole method is deemed hot for inlining, then at least C2 would inline it without looking back at its intrinsic status. Which silently breaks blackholes.
>> 
>> The cause is that there are *two* places where intrinsic ID is recorded. Current blackhole code only writes down blackhole intrinsic ID in `Method::intrinsic_id()`, but we should also set it in `ciMethod::intrinsic_id()`, which is used from C2 inlining code. `ciMethod` is normally populated from `Method::intrinsic_id()`, but it happens too early, before setting up blackhole intrinsic. 
>> 
>> Additional testing:
>>  - [x] Linux x86_64 {fastdebug,release}, wew test fails before the patch, passes with it
>>  - [x] Linux x86_64 {fastdebug,release} `compiler/blackhole`
>>  - [ ] Linux x86_64 fastdebug, sanity microbenchmark corpus run with the patch
>
> Aleksey Shipilev has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Negative test

Good. Need to test it.

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PR: https://git.openjdk.java.net/jdk/pull/8344