[PATCH] D12455: [IR] Teach `llvm::User` to co-allocate a descriptor.

[Pete Cooper via llvm-commits]

pete added a subscriber: pete.
pete added a comment.

This is just a question, not intended to block the commit if someone else gives a LGTM.

Have you considered making use of 'hung off uses' instead of adding DescBytes to new?

It would take a little work to change 'hung off uses' to actually be 'hung off bytes', and i haven't looked to see how possible that is, but it feels to me like it should be considered.

This also has the advantage of moving the desc bytes handling out of new so that all User's don't pay the price for checking them in new, and instead the rare case of meeting extra bytes can get them only on request.

Just my 2c though.

Cheers,
Pete


http://reviews.llvm.org/D12455