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

[Hal Finkel via Phabricator via llvm-commits]

hfinkel added a comment.

In https://reviews.llvm.org/D37093#858860, @majnemer wrote:

> Seems fragile. What if we run optimizations and transform the IR to another, different, version of the IR but the alloca is not promotable anymore? On occasion, the compiler can pessimize a code sequence and coroutine lowering should be resilient to such things.


I agree. If we take a step back, what's necessary to make the current algorithm sound in general?


https://reviews.llvm.org/D37093