Re: eliminating array bounds checking overhead

>>>>> "Mark" == Mark Williams <markw65@my-deja.com> writes:
> If hi & lo are constants, then it is a very reasonable transformation
> to expect the compiler to perform (on architectures where it is
> beneficial). If not, then it is unlikely to be able to. Its not a
> performance issue, its a correctness one: the two forms are only
> equivalent when hi > lo.


Very very very few languages allow arrays where the high bound is
lower then the low bound. So the only "interesting case is when
lo==hi, but that is also rare enough to be either disallowed or
handled specially.


                Stefan

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