[PATCH] D45379: [LoopInterchange] Ignore debug intrinsics during legality checks.

[Florian Hahn via Phabricator via llvm-commits]

fhahn added inline comments.


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Comment at: lib/Transforms/Scalar/LoopInterchange.cpp:82
+template <typename T>
+static auto skipDebugIntrinsics(iterator_range<T> Iter)
+    -> decltype(make_filter_range(Iter, isDebugIntrinsic)) {
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mattd wrote:
> vsk wrote:
> > fhahn wrote:
> > > vsk wrote:
> > > > aprantl wrote:
> > > > > This adapter should really be available in BasicBlock.h or somewhere more accessible if it doesn't exist already. Could you move it there (or elsewhere appropriate) and add a doxygen comment?
> > > > + 1, I think having `iterator_range<iterator> instructions()` and `... instructions_nodbg()` in BasicBlock would be nice.
> > > Ok great, I will move it there. Do you think we should just have a member function `instructionsNodbg()` or a function taking an instruction iterator and returning a filtered iterator? It's just a question how we want to compose it with things like reverse
> > I think we should have both. We'd need 'skipDebugIntrinsics' to implement 'instructionsNodbg', and 'instructionsNodbg' would make it easier to write correct code going forwards.
> > 
> > Wdyt of placing 'skipDebugIntrinsics' in IR/DebugInfo.h?
> I'm a bit late to the party here, but have been keeping an eye on this discussion.  I really like this idea.  What about exposing this in IR/Intrinisics.h instead?  For instance, what if there were other intrinsics that we would like to skip over as well (e.g., lifetime.start, lifetime.end).  In that case I can imagine (in the future) an iterator that takes a list of types to skip-over, like a parameter pack or something, although I'm not sure if that would work with  make_filter_range, just a thought.
Having an easy way to skip all kinds of instructions sounds like a great idea. I will try to put initial patches together in the next few days.


https://reviews.llvm.org/D45379