[PATCH] D110613: [Taildup] Don't tail-duplicate loop header with multiple successors as its latches

Fri Oct 8 23:34:53 PDT 2021

junparser added a comment.

In D110613#3037724 <https://reviews.llvm.org/D110613#3037724>, @alexfh wrote:

> In D110613#3029276 <https://reviews.llvm.org/D110613#3029276>, @junparser wrote:
>
>> So this change blocks optimization from D106056 <https://reviews.llvm.org/D106056>,  @alexfh  would you like to workaround with  -mllvm -tail-dup-indirect-size=4？
>
> I found a single huge protobuf generated source that was pushed over the time limit. However, there are likely many others that will just take more time to compile wasting resources and potentially increasing build latency. Having to hunt down all of them and to sprinkle `-mllvm -tail-dup-indirect-size=4` all around the build configuration files would be unfortunate.
>
>> Or let add one more parameter such as -tail-dup-jmptable-size with default value maybe 100?
>> any suggest？
>
> Would that stop this particular transformation for large switch cases?  Should this always be done?

Sorry for the late reply.  I believe this should stop to tail duplicate large jump table loop generated by switch loop.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D110613/new/

https://reviews.llvm.org/D110613