[all-commits] [llvm/llvm-project] 0c6dc8: BalancedPartitioning: minor updates (#77568)

[Fangrui Song via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 0c6dc80531ed332e346934019095ad9518f465f3
      https://github.com/llvm/llvm-project/commit/0c6dc80531ed332e346934019095ad9518f465f3
  Author: Fangrui Song <i at maskray.me>
  Date:   2024-01-17 (Wed, 17 Jan 2024)

  Changed paths:
    M llvm/lib/ProfileData/InstrProf.cpp
    M llvm/lib/Support/BalancedPartitioning.cpp
    M llvm/unittests/ProfileData/BPFunctionNodeTest.cpp

  Log Message:
  -----------
  BalancedPartitioning: minor updates (#77568)

When LargestTraceSize is a power of two, createBPFunctionNodes does not
allocate a group ID for Trace[LargestTraceSize-1] (as N is off by 1).
Fix
this and change floor+log2 to Log2_64.

BalancedPartitioning::bisect can use unstable sort because `Nodes`
contains distinct `InputOrderIndex`s.

BalancedPartitioning::runIterations: use one DenseMap and simplify the
node renumbering code.