RFR: 8240772: x86_64: Pre-generate Assembler::popa, pusha and vzeroupper

[Ioi Lam]

Looks good!

- Ioi

On 3/11/20 2:36 PM, Claes Redestad wrote:
> On 2020-03-11 19:29, Vladimir Kozlov wrote:
>>
>> That leads to question. Claes, what was the reason you used loop 
>> instead of memcpy for vzeroupper?
>
> For UseAXV <= 2 then vzeroupper is 3 bytes, so the loop simply used
> fewer instructions. It doesn't seem to matter much in the end, so let's
> favor simplicity.
>
> Final(?) version: http://cr.openjdk.java.net/~redestad/8240772/open.02/
>
> /Claes