[PATCH] D83153: [DAGCombiner] Prevent regression in isMulAddWithConstProfitable

Tue Jul 7 05:53:06 PDT 2020

benshi001 marked 4 inline comments as done.
benshi001 added a comment.

Change list according to all your comments.

1. Seperate the test cases to show improvement in another patch.

Done. https://reviews.llvm.org/D83159

2. Make sure c1 and c2 do not exceed int64, to avoid assert failure.

Done. One more if-statment is added to check that.

3. Check if c1*c2 is overflow.

Done One more if-statment for that is added.

4. Add a new test case case triggers the overflow check.

I will do that in  https://reviews.llvm.org/D83159

5. Make a inverse transform if "opt -instcombine" has been performed.

Shall we seperate this inverse transform in another patch? At least this patch improves
the test case urem-seteq-nonzero.ll, and the case in https://reviews.llvm.org/D83159

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D83153/new/

https://reviews.llvm.org/D83153