RFR: 8217745: ZGC: Simplify ZLoadBarrierStubC1

[Nils Eliasson]

Looks good,

// Nils

On 2019-01-28 09:54, Per Liden wrote:
> We can simplify ZLoadBarrierStubC1 a little bit since we know that 
> _ref_addr is always a LIR_Address and never a Register. In the 
> ZLoadBarrierStubC1 constructor we can just assert that this is always 
> true. Later, when emitting code, we can just use the presence of the 
> tmp register as indicator that we need to load the effective address.
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8217745
> Webrev: http://cr.openjdk.java.net/~pliden/8217745/webrev.0
>
> /Per