[all-commits] [llvm/llvm-project] d72750: [SimplifyCFG] Remove one-use limitation in FoldCon...

[Nikita Popov via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: d727505e40cde2ec5f8e9f4dc2220503f2b1863a
      https://github.com/llvm/llvm-project/commit/d727505e40cde2ec5f8e9f4dc2220503f2b1863a
  Author: Nikita Popov <npopov at redhat.com>
  Date:   2022-04-20 (Wed, 20 Apr 2022)

  Changed paths:
    M llvm/lib/Transforms/Utils/SimplifyCFG.cpp
    M llvm/test/Transforms/SimplifyCFG/jump-threading.ll

  Log Message:
  -----------
  [SimplifyCFG] Remove one-use limitation in FoldCondBranchOnPHI()

BlockIsSimpleEnoughToThreadThrough() already checks that the phi
(and all other instructions) are not used outside the block, so
this one-use check is not necessary for legality. I also don't
see any reason why it would be necessary for profitability (in
fact, those extra uses will be replaced with constants, which
should be generally profitable).