Use snippets in LIRGenerator

[D.Sturm]

>
> You shouldn't create new control flow in the LIR. A better way to do this
> in the high level graph, then you can still profit from subsequent
> optimizations on the control flow.
>
Something like this was what I was hoping for, great.


> I already have code that introduces the explicit division-by-zero checks
> using Snippets. I'll send it to you later in a direct email.
> You can look at AMD64HotSpotLoweringProvider and AMD64ConvertSnippets for
> how this is done.

Got the code and am already looking at integrating it. Looks
straightforward to adapt to my code.

thanks to both of you,
-- Daniel