[all-commits] [llvm/llvm-project] 241c2d: [AIX][Power10] Restrict prefixed instructions from...

[Victor Huang via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 241c2da4064c850d58896e0a870b0c3485dfd82d
      https://github.com/llvm/llvm-project/commit/241c2da4064c850d58896e0a870b0c3485dfd82d
  Author: Victor Huang <wei.huang at ibm.com>
  Date:   2021-04-27 (Tue, 27 Apr 2021)

  Changed paths:
    M llvm/include/llvm/Support/TargetRegistry.h
    M llvm/lib/Target/PowerPC/MCTargetDesc/CMakeLists.txt
    M llvm/lib/Target/PowerPC/MCTargetDesc/PPCMCTargetDesc.cpp
    A llvm/lib/Target/PowerPC/MCTargetDesc/PPCXCOFFStreamer.cpp
    A llvm/lib/Target/PowerPC/MCTargetDesc/PPCXCOFFStreamer.h
    A llvm/test/CodeGen/PowerPC/aix-prefixed-instruction-boundary.mir

  Log Message:
  -----------
  [AIX][Power10] Restrict prefixed instructions from crossing the 64byte boundary

This patch adds the support to restrict prefixed instruction from
crossing the 64 byte boundary:
- Add the infrastructure to register a custom XCOFF streamer
- Add a custom XCOFF streamer for PowerPC to allow us to
  intercept instructions as they are being emitted and align all 8 byte
  instructions to a 64 byte boundary if required by adding a 4 byte nop.

Reviewed By: stefanp

Differential Revision: https://reviews.llvm.org/D101107