[all-commits] [llvm/llvm-project] 905850: [BOLT] Deprecate hfsort+ in favor of cdsort (#72408)

[spupyrev via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 9058503d2690022642d952ee80ecde5ecdbc79ca
      https://github.com/llvm/llvm-project/commit/9058503d2690022642d952ee80ecde5ecdbc79ca
  Author: spupyrev <spupyrev at users.noreply.github.com>
  Date:   2024-01-26 (Fri, 26 Jan 2024)

  Changed paths:
    M bolt/include/bolt/Passes/HFSort.h
    M bolt/lib/Passes/CMakeLists.txt
    R bolt/lib/Passes/HFSortPlus.cpp
    M bolt/lib/Passes/ReorderFunctions.cpp

  Log Message:
  -----------
  [BOLT] Deprecate hfsort+ in favor of cdsort (#72408)

A new function sorting algorithm (cdsort) in LLVM is an optimized 
version of BOLT's hfsort+. In order to avoid code duplication and 
simplify maintenance, getting rid of hfsort+.

Perf-wise this is likely a neutral change, though differences on 
individual benchmarks are possible, since the generated function layout 
has changed. I tested cdsort vs hfsort+ on a number of open-source and 
prod binaries built in different modes and record an average neutral 
perf difference, perhaps with more "green" counters.