RFR: 8255287: aarch64: fix SVE patterns for vector shift count

[Fei Yang]

On Fri, 23 Oct 2020 10:05:31 GMT, Andrew Dinn <adinn at openjdk.org> wrote:

>> SVE patterns for vector shift count cannot be matched due to bad matching rules.
>> Also code gen is not correct in certain cases for vlslS_imm and vlsrS_imm.
>> Please refer to JDK-8255287 for details.
>> Patch passed tier1 tests using QEMU system emulator which supports SVE.
>
> These changes look ok.

Thanks for the quick review :-)  @adinn

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PR: https://git.openjdk.java.net/jdk/pull/827