[all-commits] [llvm/llvm-project] eb35eb: [LV] Update CFG before adding runtime checks.

[Florian Hahn via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: eb35ebb3a2c6db62ec54efdaff23e4f31d118c85
      https://github.com/llvm/llvm-project/commit/eb35ebb3a2c6db62ec54efdaff23e4f31d118c85
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2020-08-30 (Sun, 30 Aug 2020)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
    A llvm/test/Transforms/LoopVectorize/pr47343-expander-lcssa-after-cfg-update.ll

  Log Message:
  -----------
  [LV] Update CFG before adding runtime checks.

addRuntimeChecks uses SCEVExpander, which relies on the DT/LoopInfo to
be up-to-date. Changing the CFG afterwards may invalidate some inserted
instructions, especially LCSSA phis.

Reorder the code to first update the CFG and then create the runtime
checks. This should not have any impact on the generated code, as we
adjust the CFG and generate runtime checks together.

Fixes PR47343.