[all-commits] [llvm/llvm-project] 3f571b: [ARM] Make t2DoLoopStartTP a terminator

[David Green via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 3f571be1c07b48846f9c1ff31c088b00c3ef1f13
      https://github.com/llvm/llvm-project/commit/3f571be1c07b48846f9c1ff31c088b00c3ef1f13
  Author: David Green <david.green at arm.com>
  Date:   2020-12-11 (Fri, 11 Dec 2020)

  Changed paths:
    M llvm/lib/Target/ARM/ARMBaseInstrInfo.h
    M llvm/lib/Target/ARM/ARMInstrThumb2.td
    M llvm/lib/Target/ARM/MVEVPTOptimisationsPass.cpp
    M llvm/test/CodeGen/Thumb2/LowOverheadLoops/exitcount.ll
    M llvm/test/CodeGen/Thumb2/LowOverheadLoops/mov-operand.ll
    M llvm/test/CodeGen/Thumb2/LowOverheadLoops/reductions.ll
    M llvm/test/CodeGen/Thumb2/LowOverheadLoops/while-loops.ll
    M llvm/test/CodeGen/Thumb2/mve-fma-loops.ll
    M llvm/test/CodeGen/Thumb2/mve-gather-scatter-tailpred.ll
    M llvm/test/CodeGen/Thumb2/mve-postinc-dct.ll
    M llvm/test/CodeGen/Thumb2/mve-postinc-lsr.ll
    M llvm/test/CodeGen/Thumb2/mve-pred-vctpvpsel.ll
    M llvm/test/CodeGen/Thumb2/mve-vecreduce-loops.ll

  Log Message:
  -----------
  [ARM] Make t2DoLoopStartTP a terminator

Although this was something that I was hoping we would not have to do,
this patch makes t2DoLoopStartTP a terminator in order to keep it at the
end of it's block, so not allowing extra MVE instruction between it and
the end. With t2DoLoopStartTP's also starting tail predication regions,
it also marks them as having side effects. The t2DoLoopStart is still
not a terminator, giving it the extra scheduling freedom that can be
helpful, but now that we have a TP version they can be treated
differently.

Differential Revision: https://reviews.llvm.org/D91887