[PATCH] D48239: [LangRef] Clarify meaning of "dereferencable" attribute/metadata.

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

It's straightforward to define the alternative semantics where it only applies at the point of the call/load.  And it would still be useful to the optimizer.  But the optimizer code would have to be written from scratch; the existing getPointerDereferenceableBytes API isn't usable with an attribute like that.  It's probably worth doing at some point, though: we could prove other interesting things with the context-sensitive analysis, though.  For example, we could prove that a pointer is dereferenceable using a previous load or store operation.)


Repository:
  rL LLVM

https://reviews.llvm.org/D48239