RFR(XS): shenandoah_wb should fallback to slow path with -UseTLAB

[Aleksey Shipilev]

On 06/15/2017 10:40 PM, Zhengyu Gu wrote:
> When UseTLAB = false, gclab and tlab are not properly initialized. shenandoah_wb
> should just fallback to slow path immediately.
> 
> Please pay additional attention to aarch64, as I am not familiar with ARM 64
> instructions and have not test machine.
> 
> Webrev: http://cr.openjdk.java.net/~zgu/shenandoah/shbs_no_tlab/webrev.00/

Seems fine.

-Aleksey