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Re: basic_block index negative?
On Wed, 17 Oct 2001, Daniel Egger wrote:
> Am Mit, 2001-10-17 um 19.46 schrieb 1003340807:
> > Dunno. I guess because they're special and contain no program
> > instructions. The tree SSA code uses it to tell whether it found
> > a ghost definition (artificial definitions created by SSA).
> I find it quite odd and distracting to have negative indices. This
> also forbids using them for arrays.
> I think it would be really nice to mostly unsigned variables; this
> makes it easy to prevent nasty sideeffects when dealing with them
> and quite frankly I don't like the just of casts in the code. Maybe
> gcc could also create better code but this is just a speculation
> for recent versions, it worked on older versions though.
Even if you didn't allow negative indices, reverse traversals are
important. Making the index unsigned would make them more
interesting than they need to be.