[all-commits] [llvm/llvm-project] a2332d: [ARM] Prevent continuous folding of SUBC

[David Green via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: a2332d5332c3ede49adf1c71481e9efab7ca88c7
      https://github.com/llvm/llvm-project/commit/a2332d5332c3ede49adf1c71481e9efab7ca88c7
  Author: David Green <david.green at arm.com>
  Date:   2021-09-15 (Wed, 15 Sep 2021)

  Changed paths:
    M llvm/lib/Target/ARM/ARMISelLowering.cpp
    M llvm/test/CodeGen/ARM/select_const.ll

  Log Message:
  -----------
  [ARM] Prevent continuous folding of SUBC

Under some situations under Thumb1, we could be stuck in an infinite
loop recombining the same instruction. This puts a limit on that, not
combining SUBC with SUBE repeatedly.