[PATCH] D24854: [SROA] Drop lifetime.start/end intrinsics when they block promotion.

[Chandler Carruth via llvm-commits]

chandlerc added a comment.

In https://reviews.llvm.org/D24854#602150, @kcc wrote:

> +Vitaly, as this may affect asan's stack-use-after-scope detection.


In case following the thread is confusing: the suggested approach here may cause false *negatives* for ASan + https://reviews.llvm.org/owners/package/2/ + stack-use-after-scope. But anything Eli does here otherwise will regress ASan + https://reviews.llvm.org/owners/package/2/ performance dramatically and fix an unknown number of current false negatives.

So I suspect the ASan folks will want to pursue changes here to reduce false negatives in a separate change where you can both avoid the optimization regressions and control enabling these checks to not suddenly expose large numbers of new failures to a check that is already deployed.


Repository:
  rL LLVM

https://reviews.llvm.org/D24854