RFR: 8266388: C2: Improve constant ShiftCntV on x86

Fri Apr 30 20:07:50 UTC 2021

On Fri, 30 Apr 2021 19:18:37 GMT, Vladimir Ivanov <vlivanov at openjdk.org> wrote:

> Clone ShiftCntV w/ a constant input during matching on x86. 
> It enables `vshiftI_imm`/`vshiftL_imm` when ShiftCntV is shared.
> 
> Testing:
> - [x] hs-tier1 - hs-tier4

Good.

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Marked as reviewed by kvn (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/3823