[InstSimplify] Drop redundant icmp(ptrtoint, const) fold #171988
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I believe this fold isn't going to do anything useful: If the constant is 0, then we'll already handle this via isKnownNonZero(). If the constant is non-zero, we'll create an inttoptr constant expression, and as far as I can tell we don't have any InstSimplify folds that would apply for that case.
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Looks like the case where this makes a difference if if we're comparing ptrtoint of a phi node. In that case threadCmpOverPhi() does full recursion, while isKnownNonZero() only does partial. Might still make sense to drop as this seems rather niche, but it's clearly not NFC at least... |
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I believe this fold isn't going to do anything useful: If the constant is 0, then we'll already handle this via isKnownNonZero(). If the constant is non-zero, we'll create an inttoptr constant expression, and as far as I can tell we don't have any InstSimplify folds that would apply for that case.