RFR(M): 8213134: AArch64: vector shift failed with MaxVectorSize=8

[Yang Zhang (Arm Technology China)]

Hi,

When I implemented AArch64 NEON for Vector API (http://openjdk.java.net/jeps/338), I found an issue about vector shift. I have a patch which could fix this issue. Could anyone help to review this patch?

Webrev: http://cr.openjdk.java.net/~yzhang/8213134/webrev.01/
JBS:  https://bugs.openjdk.java.net/browse/JDK-8213134

This patch is verified both in jdk/jdk master and panama/vectorIntrinsics, and tests are passed.
Hotspt jtreg contains the following test cases that can cover all the patterns of vector shift.  But only default option "-XX:MaxVectorSize=64" is tested, so this issue isn't detected. Now I add "-XX:MaxVectorSize=8", "-XX:MaxVectorSize=16" and "-XX:MaxVectorSize=32" to these jtreg tests in this patch.
compiler/c2/cr6340864/TestByteVect.java
compiler/c2/cr6340864/TestIntVect.java
compiler/c2/cr6340864/TestShortVect.java
compiler/codegen/TestCharVect2.java

Regards
Yang