[PATCH] D62392: [DAGCombine][ARM] (sub Carry, X) -> (addcarry (sub 0, X), 0, Carry) fold

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri marked an inline comment as done.
lebedev.ri added a comment.

In D62392#1516829 <https://reviews.llvm.org/D62392#1516829>, @efriedma wrote:

> It looks like we don't have great test coverage here.


Yes, indeed, that is the only affected test in the entire `check-llvm-codegen`.

In D62392#1516829 <https://reviews.llvm.org/D62392#1516829>, @efriedma wrote:

> In general, we probably need to restrict getAsCarry depending on whether the intended use is an an addition or subtraction, at least for ARM.


I'm sorry, but i'm again not sure what that means (:
Restrict how?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D62392/new/

https://reviews.llvm.org/D62392