RFR(XS): 8193518: C2: Vector registers sometimes corrupted at safepoint

[Roland Westrelin]

Hi Nils,

Thanks for taking a look at this...

> You need to initalize _max_vector_size in Compile::init.

...and verifying something I didn't.

There's a:
set_max_vector_size(0);
in Compile::Init() so it should be all good.

Roland.