[PATCH] D32755: [DAGCombine] (addcarry (add|uaddo X, Y), 0, Carry) -> (addcarry X, Y, Carry)

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon accepted this revision.
RKSimon added a comment.
This revision is now accepted and ready to land.

LGTM with one minor



================
Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:2158
+  // If the flag result is dead, we can do transform that invalidate it.
+  // (addcarry (add|uaddo X, Y), 0, Carry) -> (addcarry X, Y, Carry)
+  if ((N0.getOpcode() == ISD::ADD || N0.getOpcode() == ISD::UADDO) &&
----------------
The comment doesn't grok well, maybe just:
```
// IIF the flag result is dead:
// (addcarry (add|uaddo X, Y), 0, Carry) -> (addcarry X, Y, Carry)
```



https://reviews.llvm.org/D32755