search for: r269358

...ion - places that currently call ReplaceUses() and then return nullptr often do that. There are examples of this in r269256. 2. Similarly, some places might replace all uses of a node with a new one, then return the new node. Just remove the dead node instead. There was some of this in r269358. 3. Anywhere else where Select returns a node, update it to call ReplaceNode instead (or ReplaceUses + RemoveDeadNode). All of the "Implement Select instead of SelectImpl" commits do some of this. 4. Where a utility function can return null when Select should fall back to anoth...

Thanks Ahmed and also Alex for your replies. This is more or less what I was realising, but it is a great confidence booster to know that it is the correct way also. I can replace all of my various 'Select*' specialisations with version that use 'ReplaceNode/SelectCode' and return 'void', but what about the places where I currently call 'Select(N)' directly?