Slow code due to many AbstractVector::check and AbstractShuffle::checkIndexes checks in C2

[John Rose]

On May 22, 2020, at 3:25 PM, Paul Sandoz <paul.sandoz at oracle.com> wrote:
> 
> The checkIndexes of the shuffle.checkIndexes is likely to have a cost, it's not optimized right now. 

After it’s converted to vector operations, it should be hoistable
from loops.  “Should be” != “is”, of course.