[all-commits] [llvm/llvm-project] fdb055: Reapply "[DebugInfo] Fix updateDbgUsersToReg to su...

[Stephen Tozer via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: fdb055f4f139e225884109fbffa275bd3eb3d3b9
      https://github.com/llvm/llvm-project/commit/fdb055f4f139e225884109fbffa275bd3eb3d3b9
  Author: Stephen Tozer <Stephen.Tozer at Sony.com>
  Date:   2021-05-12 (Wed, 12 May 2021)

  Changed paths:
    M llvm/include/llvm/CodeGen/MachineRegisterInfo.h
    M llvm/lib/CodeGen/MachineCopyPropagation.cpp
    A llvm/test/DebugInfo/ARM/machine-cp-updates-dbg-reg.mir

  Log Message:
  -----------
  Reapply "[DebugInfo] Fix updateDbgUsersToReg to support DBG_VALUE_LIST"

Previous crashes caused by this patch were the result of machine
subregisters being incorrectly handled in updateDbgUsersToReg; this has
been fixed by using RegUnits to determine overlapping registers, instead
of using the register values directly.

Differential Revision: https://reviews.llvm.org/D101523

This reverts commit 7ca26c5fa2df253878cab22e1e2f0d6f1b481218.