test/DebugInfo/MIR/X86/live-debug-values-entry-transfer.mir

# RUN: llc %s -o - -run-pass=livedebugvalues -mtriple=x86_64-unknown-unknown | FileCheck %s
#
# In this lightly modified test case, the transfer in the entry block from
# geti32's return value in $eax to the non-volatile $ebx should be recognized,
# and propagated throughout the whole function.
#
# CHECK-LABEL: bb.0.entry
# CHECK:       DBG_VALUE $eax
# CHECK:       DBG_VALUE $ebx
# CHECK-LABEL: bb.1.loop2
# CHECK:       DBG_VALUE $ebx
# CHECK-LABEL: bb.2.loop
# CHECK:       DBG_VALUE $ebx
# CHECK-LABEL: bb.3.exit
# CHECK:       DBG_VALUE $ebx
--- |
  ; ModuleID = 'asdf'
  source_filename = "asdf.ll"
  target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
  target triple = "x86_64-unknown-unknown"

  @glob = global i32 0

  declare i1 @booler()

  declare i32 @geti32()

  declare void @escape(i32)

  ; Function Attrs: nounwind readnone speculatable willreturn
  declare void @llvm.dbg.value(metadata, metadata, metadata)

  define i32 @foo() !dbg !4 {
  entry:
    %bar = call i32 @geti32(), !dbg !10
    call void @llvm.dbg.value(metadata i32 %bar, metadata !9, metadata !DIExpression()), !dbg !10
    br label %loop

  loop:                                             ; preds = %loop2, %entry
    call void @escape(i32 %bar)
    %retval = call i1 @booler(), !dbg !10
    br i1 %retval, label %loop2, label %exit

  loop2:                                            ; preds = %loop
    store i32 %bar, i32* @glob
    br label %loop

  exit:                                             ; preds = %loop
    ret i32 %bar
  }

  ; Function Attrs: nounwind
  declare void @llvm.stackprotector(i8*, i8**)

  !llvm.module.flags = !{!0, !1}
  !llvm.dbg.cu = !{!2}

  !0 = !{i32 2, !"Debug Info Version", i32 3}
  !1 = !{i32 2, !"Dwarf Version", i32 4}
  !2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !3, producer: "beards", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug)
  !3 = !DIFile(filename: "bees.cpp", directory: ".")
  !4 = distinct !DISubprogram(name: "nope", scope: !3, file: !3, line: 1, type: !5, spFlags: DISPFlagDefinition, unit: !2, retainedNodes: !8)
  !5 = !DISubroutineType(types: !6)
  !6 = !{!7}
  !7 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
  !8 = !{!9}
  !9 = !DILocalVariable(name: "toast", scope: !4, file: !3, line: 1, type: !7)
  !10 = !DILocation(line: 1, scope: !4)

...
---
name:            foo
tracksRegLiveness: true
frameInfo:
  stackSize:       8
  offsetAdjustment: -8
  adjustsStack:    true
  hasCalls:        true
  cvBytesOfCalleeSavedRegisters: 8
fixedStack:
  - { id: 0, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
      callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '',
      debug-info-expression: '', debug-info-location: '' }
stack:           []
body:             |
  bb.0.entry:
    successors: %bb.1(0x80000000)
    liveins: $rbx

    frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp, debug-location !10
    CFI_INSTRUCTION def_cfa_offset 16
    CFI_INSTRUCTION offset $rbx, -16
    CALL64pcrel32 @geti32, csr_64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp, implicit-def $eax, debug-location !10
    DBG_VALUE $eax, $noreg, !9, !DIExpression(), debug-location !10
    $ebx = MOV32rr killed $eax, debug-location !10
    JMP_1 %bb.1

  bb.1.loop2:
    successors: %bb.2
    liveins: $ebx

    MOV32mr $rip, 1, $noreg, @glob, $noreg, renamable $ebx :: (store 4 into @glob)

  bb.2.loop:
    successors: %bb.1, %bb.3
    liveins: $ebx

    $edi = MOV32rr $ebx
    CALL64pcrel32 @escape, csr_64, implicit $rsp, implicit $ssp, implicit killed $edi, implicit-def $rsp, implicit-def $ssp
    CALL64pcrel32 @booler, csr_64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp, implicit-def $al, debug-location !10
    TEST8ri killed renamable $al, 1, implicit-def $eflags
    JCC_1 %bb.1, 5, implicit $eflags

  bb.3.exit:
    liveins: $ebx

    $eax = MOV32rr killed $ebx
    $rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp
    CFI_INSTRUCTION def_cfa_offset 8
    RETQ $eax

...