RFR: 8287393: AArch64: Remove trampoline_call1 [v2]

[Evgeny Astigeevich]

On Thu, 21 Jul 2022 16:37:03 GMT, Evgeny Astigeevich <duke at openjdk.org> wrote:

>> `trampoline_call` can do dummy code generation to calculate the size of C2 generated code. This is done in the output phase. In [src/hotspot/cpu/aarch64/sharedRuntime_aarch64.cpp#L1042](https://github.com/openjdk/jdk/blob/e0d361cea91d3dd1450aece73f660b4abb7ce5fa/src/hotspot/cpu/aarch64/sharedRuntime_aarch64.cpp#L1042) Loom code needed to generate a trampoline call outside of C2 and without the output phase. This caused test crashes. The project Loom added `trampoline_call1` to workaround the crashes. 
>> 
>> This PR improves detection of C2 output phase which makes `trampoline_call1` redundant.
>> 
>> Tested the fastdebug/release builds:
>> - `'gtest`: Passed
>> - `tier1`...`tier2`: Passed
>
> Evgeny Astigeevich has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Replace trampoline_call1 with trampoline_call

Andrew (@theRealAph), could you please have a look?

Thanks.

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PR: https://git.openjdk.org/jdk/pull/9592