| # NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py | 
 | # RUN: llc -march=amdgcn -mcpu=gfx900 -verify-machineinstrs -run-pass=register-coalescer -o - %s | FileCheck -check-prefix=GCN %s | 
 |  | 
 | # Test used to crash with message: | 
 | # JoinVals::ConflictResolution (anonymous namespace)::JoinVals::analyzeValue(unsigned int, (anonymous namespace)::JoinVals &): Assertion `DefMI != nullptr' failed | 
 |  | 
 | --- | 
 | name:            test | 
 | tracksRegLiveness: true | 
 | body:             | | 
 |   ; GCN-LABEL: name: test | 
 |   ; GCN: bb.0: | 
 |   ; GCN-NEXT:   successors: %bb.2(0x80000000) | 
 |   ; GCN-NEXT: {{  $}} | 
 |   ; GCN-NEXT:   undef %1.sub0:vreg_128 = IMPLICIT_DEF | 
 |   ; GCN-NEXT:   %1.sub1:vreg_128 = IMPLICIT_DEF | 
 |   ; GCN-NEXT:   S_BRANCH %bb.2 | 
 |   ; GCN-NEXT: {{  $}} | 
 |   ; GCN-NEXT: bb.1: | 
 |   ; GCN-NEXT:   successors: %bb.2(0x80000000) | 
 |   ; GCN-NEXT: {{  $}} | 
 |   ; GCN-NEXT:   [[DEF:%[0-9]+]]:vreg_128 = IMPLICIT_DEF | 
 |   ; GCN-NEXT: {{  $}} | 
 |   ; GCN-NEXT: bb.2: | 
 |   ; GCN-NEXT:   [[DEF]].sub2:vreg_128 = COPY undef %3:sreg_32 | 
 |   ; GCN-NEXT:   S_ENDPGM 0, implicit [[DEF]] | 
 |   bb.0: | 
 |     undef %0.sub0:vreg_128 = IMPLICIT_DEF | 
 |     %0.sub1:vreg_128 = IMPLICIT_DEF | 
 |     %1:vreg_128 = COPY %0 | 
 |     %2:vreg_128 = COPY killed %0 | 
 |     S_BRANCH %bb.2 | 
 |  | 
 |   bb.1: | 
 |     %1:vreg_128 = COPY killed undef %1 | 
 |  | 
 |   bb.2: | 
 |     %1.sub2:vreg_128 = COPY undef %3:sreg_32 | 
 |     %2:vreg_128 = COPY killed %1 | 
 |     %4:vreg_128 = COPY killed %2 | 
 |     S_ENDPGM 0, implicit killed %4 | 
 |  | 
 | ... |