llvm-project/llvm/test/CodeGen/X86/opt_phis.mir

# RUN: llc -run-pass opt-phis -march=x86-64 -o - %s | FileCheck %s
--- |
  define void @test() {
    ret void
  }

  !llvm.dbg.cu = !{!1}
  !llvm.module.flags = !{!2, !3}
  !llvm.ident = !{!4}

  !0 = !DIFile(filename: "foo.c", directory: "/bar")
  !1 = distinct !DICompileUnit(language: DW_LANG_C, file: !0, producer: "My Compiler")
  !2 = !{i32 2, !"Dwarf Version", i32 4}
  !3 = !{i32 2, !"Debug Info Version", i32 3}
  !4 = !{!"My Compiler"}
  !5 = distinct !DISubprogram(name: "test")
  !6 = !DILocation(line: 7, column: 11, scope: !5)
  !7 = !DILocalVariable(name: "l", scope: !5)

...
---
name:            test
tracksRegLiveness: true
body:             |
  bb.0:
    %0:gr32 = IMPLICIT_DEF

  bb.1:
    %1:gr32 = PHI %0, %bb.0, %2, %bb.1
    DBG_VALUE %1, _, !7, !DIExpression(), debug-location !6
    %2:gr32 = IMPLICIT_DEF
    JMP_1 %bb.1
...

# The PHI should be removed since it's only used in a DBG_VALUE
# CHECK-LABEL: bb.1:
# CHECK-NOT: PHI