llvm/llvm/test/CodeGen/X86/branchfolding-undef.mir

# RUN: llc -o - %s -mtriple=i686-- -run-pass branch-folder | FileCheck %s
# Test that tail merging drops undef flags that aren't present on all
# instructions to be merged.
--- |
  define void @func() { ret void }
...
---
# CHECK-LABEL: name: func
# CHECK: bb.1:
# CHECK: $eax = MOV32ri 2
# CHECK-NOT: RET
# CHECK: bb.2:
# CHECK-NOT: RET 0, undef $eax
# CHECK: RET 0, $eax
name: func
tracksRegLiveness: true
body: |
  bb.0:
    JCC_1 %bb.1, 4, implicit undef $eflags
    JMP_1 %bb.2

  bb.1:
    $eax = MOV32ri 2
    RET 0, $eax

  bb.2:
    RET 0, undef $eax
...