[PATCH] D33587: [DAGCombine] Do several rounds of combine.

Mon Jan 28 17:02:17 PST 2019

craig.topper added a comment.

In D33587#1374753 <https://reviews.llvm.org/D33587#1374753>, @deadalnix wrote:

> Hi @craig.topper ,
>
> First about the kind of code I try to get to have better codegen, it's mostly about large integer manipulations. I already added a fair amount of reduced test cases in addcarry.ll/subcarry.ll . I'm at a stage where the pattern I have to work with are somewhat deep, see D57302 <https://reviews.llvm.org/D57302> for an example. These patterns do not do anything useful if other transform cannot pick up from whee they left.

I don't see changes to addcarry.ll and subborrow.ll in this patch. So do we not have test cases from your workloads that show the benefit of this patch?

Are there non-X86 changes from this patch as well that haven't been captured here? Or is X86 somehow the only target affected by this?

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D33587/new/

https://reviews.llvm.org/D33587