[all-commits] [llvm/llvm-project] 037636: [SDAG] Introduce a common MEMBARRIER node [nfc]

[Philip Reames via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 037636e695daff1834f0bda0aed52e606c7ebf9a
      https://github.com/llvm/llvm-project/commit/037636e695daff1834f0bda0aed52e606c7ebf9a
  Author: Philip Reames <preames at rivosinc.com>
  Date:   2023-01-09 (Mon, 09 Jan 2023)

  Changed paths:
    M llvm/include/llvm/CodeGen/ISDOpcodes.h
    M llvm/include/llvm/Target/TargetSelectionDAG.td
    M llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
    M llvm/lib/Target/SystemZ/SystemZISelLowering.cpp
    M llvm/lib/Target/SystemZ/SystemZISelLowering.h
    M llvm/lib/Target/SystemZ/SystemZInstrInfo.td
    M llvm/lib/Target/SystemZ/SystemZOperators.td
    M llvm/lib/Target/X86/X86ISelLowering.cpp
    M llvm/lib/Target/X86/X86ISelLowering.h
    M llvm/lib/Target/X86/X86InstrCompiler.td
    M llvm/lib/Target/X86/X86InstrInfo.td

  Log Message:
  -----------
  [SDAG] Introduce a common MEMBARRIER node [nfc]

We have multiple targets which have defined custom instructions and sdag nodes to represent a compiler memory barrier. This patch consolidates the sdag node definition into common code.

This is a companion to D92842, but a bit different in focus. This change consolidates the existing sdag node definitions; that patch skipped defining a sdag node by instead going straight to a target node. That patch is also not NFC - as being so is quite hard for commoning up the instruction definitions.

I started with two backends to ensure the new common code was reusable while not having a massive diff. Once this lands, I'll submit a series of NFCs for backends where the changes are obvious, or reviews if more discussion is needed.

Differential Revision: https://reviews.llvm.org/D141317