RFR: C1 fixes to matrix barriers

[Roman Kennke]

Am 24.03.2017 um 09:55 schrieb Andrew Haley:
> On 24/03/17 08:29, Roman Kennke wrote:
>> Yeah, but x86 can move an immediate instead, no need to take a register
>> there.
>> AArch64's const2mem() would only move a zero.
> And this is worth splattering #ifdefs over shared code?  And there
> is a speed gain?  In C1?
Hmm, right. No.

http://cr.openjdk.java.net/~rkennke/c1matrixbarrier/webrev.01/
<http://cr.openjdk.java.net/%7Erkennke/c1matrixbarrier/webrev.01/>

Better?

Roman