[PATCH] D37093: [coroutines] Promote cleanup.dest.slot-like allocas to registers to avoid storing them in the coroutine frame

[Gor Nishanov via Phabricator via llvm-commits]

GorNishanov added a comment.

> I still don't see what checking that the type is an integer or the value is a constant buys you. Why can't you look for allocas that are used after the call to llvm.coro.free? Isn't that the relevant factor?

The problem this patch is fixing only occurs in -O0, at any other optimization levels, mem2reg pass during SROA eliminates all of the cleanup related allocas (and more).
I do not want to promote all promotable allocas, I only would like to target cleanup allocas (flags and dest.slot), so I am looking for a pattern used in those, namely, those are integer allocas that have only constants stored in them.


https://reviews.llvm.org/D37093