RFR: 8286104: use aggressive liveness for unstable_if traps [v2]

[Xin Liu]

On Thu, 26 May 2022 20:15:05 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

> You need to verify that calls are removed from lists (for example call valueOf() from _boxing_late_inlines list).  If calls are indeed removed from lists by calling igvn.optimize() then I will be fine with your code.

Hi，@vnkozlov , 

from my reading, `valueOf()` in this [example](https://github.com/openjdk/jdk/pull/8545/files#diff-77b63ebfe062d7bec62f831c7a5f2c77ad9767f3d4a6be87ea22337e50b70192R47)  is removed in late-inliner.  It is pure and nobody consumes its return value.  This is my goal in this PR. 

I will explore full-fledged useless elimination after [JDK-8287385](https://bugs.openjdk.java.net/browse/JDK-8287385). I think it can reveal more chances than this.  I clean up this patch. could you take a look at this? 

thanks,
--lx

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PR: https://git.openjdk.java.net/jdk/pull/8545