[PATCH] D75845: [ValueLattice] Add singlecrfromundef lattice value.

Tue Mar 17 07:57:38 PDT 2020

fhahn marked an inline comment as done.
fhahn added inline comments.

================
Comment at: llvm/include/llvm/Analysis/ValueLattice.h:44
+    /// Transition allowed to the following states:
+    ///  constant
+    ///  singlecrfromundef
----------------
efriedma wrote:
> fhahn wrote:
> > efriedma wrote:
> > > Is there actually a transition from undef -> constant?
> > Yes it is allowed in `mergeIn()`, which also ensures going to overdefined if we merge a constant with a different constant.
> Oh, I see.  It's probably worth calling out in the documentation for constant: it might actually come from an undef/constant merge, like singlecrfromundef.  (I don't think it has any practical impact at the moment, but it could matter in the future.)
Should be added in 873ab73db477

Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D75845/new/

https://reviews.llvm.org/D75845