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Re: How to check that two ssa registers have the same symbolic value


On 5/29/07, Jeffrey Law <law@redhat.com> wrote:


Note that this form of code hoisting is generally a win from a codesize standpoint. We have an RTL implementation, but not a tree-ssa implementation IIRC.

tree level PRE knows it could hoist these things (and they are marked as such), but we simply don't do it because it's not a partial redundancy. IE they are all marked antic at the beginning of the block.

I've never bothered to teach it there are other times it might be
profitable to move calculations anyway.


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