[all-commits] [llvm/llvm-project] 8e8d21: [NFCI][SimplifyCFG] Prefer to add Insert edges bef...

[Roman Lebedev via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 8e8d214c4a6c417e42996faeb9211a5c2e32111f
      https://github.com/llvm/llvm-project/commit/8e8d214c4a6c417e42996faeb9211a5c2e32111f
  Author: Roman Lebedev <lebedev.ri at gmail.com>
  Date:   2021-01-11 (Mon, 11 Jan 2021)

  Changed paths:
    M llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
    M llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
    M llvm/lib/Transforms/Utils/Local.cpp
    M llvm/lib/Transforms/Utils/SimplifyCFG.cpp

  Log Message:
  -----------
  [NFCI][SimplifyCFG] Prefer to add Insert edges before Delete edges into DomTreeUpdater, if reasonable

This has a measurable impact on the number of DomTree recalculations.
While this doesn't handle all the cases,
it deals with the most obvious ones.