I added a simple guard elimination pass to the compiler. This should be done very late in the pipeline, since it benefits from load elimination (which we don’t do yet but will do soon). Currently I only eliminate redundant null guards that point directly to an object allocation. Since we are in SSA, and in particular once we do load elimination, this should catch all redundant null checks on locally allocated objects.

The other common case we should optimize for are null checks on the this pointer. This should be pretty straight forward to detect. The this pointer is in context slot 0. In case of inlined method calls the this pointer will be passed in as argument, but since we are in SSA and do copy propagation the direct link to slot 0 in the anchor context will be visible even for such inlined uses of the this pointer.

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