[all-commits] [llvm/llvm-project] 87debd: [VectorCombine] check instruction type before disp...

[Sanjay Patel via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 87debdadaf18f8a5c7e5d563889e10731dc3554d
      https://github.com/llvm/llvm-project/commit/87debdadaf18f8a5c7e5d563889e10731dc3554d
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2022-11-18 (Fri, 18 Nov 2022)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/VectorCombine.cpp

  Log Message:
  -----------
  [VectorCombine] check instruction type before dispatching to folds

This is no externally visible change intended, but appears to be a
noticeable (surprising) improvement in compile-time based on:
https://llvm-compile-time-tracker.com/compare.php?from=0f3e72e86c8c7c6bf0ec24bf1e2acd74b4123e7b&to=5e8c2026d10e8e2c93c038c776853bed0e7c8fc1&stat=instructions:u

The early returns in the individual fold functions are not good
enough to avoid the overhead of the many "fold*" calls, so this
speeds up the main instruction loop enough to make a difference.