[all-commits] [llvm/llvm-project] bacddf: [amdgpu] Fix a crash case when preserving MDT in S...

[darkbuck via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: bacddf47a8381f52baebaaa41a2c482c156b6f01
      https://github.com/llvm/llvm-project/commit/bacddf47a8381f52baebaaa41a2c482c156b6f01
  Author: Michael Liao <michael.hliao at gmail.com>
  Date:   2021-10-15 (Fri, 15 Oct 2021)

  Changed paths:
    M llvm/lib/Target/AMDGPU/SILowerControlFlow.cpp
    A llvm/test/CodeGen/AMDGPU/mdt-preserving-crash.ll

  Log Message:
  -----------
  [amdgpu] Fix a crash case when preserving MDT in SILowerControlFlow

- When a redundant MBB is being erased from MDT, check whether its
  single successor is dominiated by it. If yes, update that successor's
  idom before erasing MBB; otherwise, it implies MBB is a leaf node and
  could be erased directly.

Reviewed By: foad

Differential Revision: https://reviews.llvm.org/D111831