[llvm] [CodeLayout] cache-directed sort: limit max chain size (PR #69039)

[via llvm-commits]

spupyrev wrote:

Thanks a lot for speeding this up!

Can we apply the density-based condition, as in https://github.com/llvm/llvm-project/pull/68617? Besides making the code faster, it is often helps for quality too. I'd keep the max-chain-size to be 512, if possible (assuming in conjunction with the density-based check the runtime is low).

https://github.com/llvm/llvm-project/pull/69039