[PATCH] D152833: A new code layout algorithm for function reordering [1/3]

[Sergey Pupyrev via Phabricator via llvm-commits]

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We are brining a new algorithm for function layout (reordering) based on the
call graph (extracted from a profile data). The algorithm is an improvement of
top of a known heuristic, C^3. It tries to co-locate hot and frequently executed
together functions in the resulting ordering. Unlike C^3, it explores a larger
search space and have an objective closely tied to the performance of 
instruction and i-TLB caches. Hence, the name CDS = Cache-Directed Sort.
The algorithm can be used at the linking or post-linking (e.g., BOLT) stage.

This diff modifies the existing data structures to facilitate the implementation 
(down the stack). This is a no-op change.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D152833

Files:
  llvm/lib/Transforms/Utils/CodeLayout.cpp

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