aarch64: RFR: Block zeroing by 'DC ZVA'

[Andrew Haley]

On 04/18/2016 09:10 AM, Edward Nevill wrote:
> I have benchmarked this on 3 different partners HW using the following JMH test case
> 
> http://people.linaro.org/~edward.nevill/jmh/test/src/main/java/org/sample/JMHTest_00_StringConcatTest.java

This isn't a great test for block zeroing.  Nevertheless, I have
approved this patch, with a few alterations.

A note about using jmh, not just for you but for everyone working on
this project.  Don't do something like

for (int i = 0; i < 10000; i++)
    theTest();

as an attempt to pad out the execution time.  jmh is much better at
this sort of thing than you are.  Just put the code you're trying to
test in the test case.

Andrew.