I don't think that the current trySub() lowering handles this.
We could handle it either using a second pattern match rule, or by recognizing the zero immediate inside trySub().
Created attachment 264750 [details]
Comment on attachment 264750 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=264750&action=review
> +StoreSubLoad = Store(Sub(left, right), address)
Landed in http://trac.webkit.org/changeset/191996