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

Wed Oct 20 01:48:37 PDT 2021

junparser added a comment.

In D110613#3054593 <https://reviews.llvm.org/D110613#3054593>, @lkail wrote:

> I agree we should add limitation to such pattern of CFG. If not, quadratic number of edges are added to CFG and hurt compile-time, especially when there are 1K+ cases. The setting of `tail-dup-jmptable-loop-size` might be related to BTB or BTAC, of which I'm not an expert. But for now, we don't want to regress protobuf's compile-time, value of `128` need @alexfh 's confirm.

@alexfh, would you have a try with this patch?

Repository:
  rG LLVM Github Monorepo

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

https://reviews.llvm.org/D110613