RFR(M): 8195112: x86 (32 bit): implementation for Thread-local handshakes

[Doerr, Martin]

Hi,

I think supporting Thread-local handshakes on all platforms will make future changes easier, because some new features may require it.
At least, I prefer to treat 32 bit like the 64 bit version. So I just implemented it for x86 (32 bit).

Please review:
http://cr.openjdk.java.net/~mdoerr/8195112_x86_local_poll/webrev.00/

I've ran a couple of tests on linux and Windows. Maybe someone else still supports 32 bit and wants to run additional tests?
I haven't done performance comparisons, because it's not so critical for us on 32 bit.

I will also need a sponsor.

Best regards,
Martin