RFR(XS) 8223215: Shenandoah: Support verifying subset of roots

[Aleksey Shipilev]

On 5/10/19 11:14 PM, Zhengyu Gu wrote:
> 
> On 5/10/19 3:12 PM, Roman Kennke wrote:
>> Hi Zhengyu,
>>
>> this looks good.
>> Maybe the root-verifier code should be in its own files?
> 
> Updated: http://cr.openjdk.java.net/~zgu/JDK-8223215/webrev.01/

Stylistic nits:

*) New line is missing here in shenandoahRootVerifier.cpp?

  54   }
  55   if (verify(CLDGRoots)) {

*) You sure uint is not too narrow here? I think it's fine, but maybe casting through uintptr_t is
safer?

  42 void ShenandoahRootVerifier::excludes(RootTypes types) {
  43   _types = static_cast<ShenandoahRootVerifier::RootTypes>(static_cast<uint>(_types) &
(~static_cast<uint>(types)));
  44 }


-Aleksey