llvm/llvm/test/CodeGen/AMDGPU/coalescer-identical-values-undef.mir

# RUN: llc -mtriple=amdgcn--amdpal -run-pass=register-coalescer -o - %s | FileCheck %s

# Check that this doesn't crash. Check for some legitimate output.
# CHECK: S_CBRANCH_SCC1

---
name: fred
tracksRegLiveness: true
body: |
  bb.0:
    successors: %bb.1, %bb.2
    liveins: $sgpr4
    undef %0.sub2:sgpr_128 = COPY $sgpr4
    %3 = IMPLICIT_DEF
    S_CBRANCH_SCC1 %bb.2, implicit undef $scc

  bb.1:
    successors: %bb.2
    %0.sub0:sgpr_128 = COPY %0.sub2
    %0.sub1:sgpr_128 = COPY %0.sub2
    %1:sgpr_128 = COPY %0
    %2:sgpr_128 = COPY %0
    %0:sgpr_128 = COPY %2
    %3:sgpr_128 = COPY %1

  bb.2:
    $sgpr1 = COPY %3
    $sgpr2 = COPY %0.sub2
...