llvm/test/DebugInfo/MIR/InstrRef/ignore-dbg-value-list.mir

# RUN: llc %s -o - -mtriple=x86_64-unknown-unknown \
# RUN:    -experimental-debug-variable-locations -run-pass=livedebugvalues\
# RUN:    | FileCheck %s --implicit-check-not=DBG_VALUE \
# RUN:                   --implicit-check-not=DBG_VALUE_LIST
#
# Test that any DBG_VALUE_LISTs observed are interpreted as DBG_VALUE $noreg.
# This is obviously sub-optimal, but avoids false variable locations, for the
# period of time until InstrRefBasedLDV supports these variable locations.
# 
--- |
  target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
  target triple = "x86_64-unknown-linux-gnu"
  
  define dso_local i32 @foo() !dbg !7 {
  entry:
    ret i32 0
  }
  
  !llvm.dbg.cu = !{!0}
  !llvm.module.flags = !{!3, !4, !5}
  !llvm.ident = !{!6}
  
  !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, splitDebugInlining: false, nameTableKind: None)
  !1 = !DIFile(filename: "test.c", directory: "/tmp/out.c")
  !2 = !{}
  !3 = !{i32 7, !"Dwarf Version", i32 4}
  !4 = !{i32 2, !"Debug Info Version", i32 3}
  !5 = !{i32 1, !"wchar_size", i32 4}
  !6 = !{!""}
  !7 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 3, type: !8, scopeLine: 3, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
  !8 = !DISubroutineType(types: !9)
  !9 = !{!10, !11, !11}
  !10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
  !11 = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
  !12 = !DILocalVariable(name: "bar", arg: 1, scope: !7, file: !1, line: 3, type: !11)
  !13 = !DILocation(line: 0, scope: !7)
  !14 = !DILocalVariable(name: "baz", arg: 2, scope: !7, file: !1, line: 3, type: !11)

...
---
name:            foo
alignment:       16
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  bb.0:
    liveins: $rdi, $rsi, $r14, $rbx

    ; CHECK-LABEL: bb.0:
    $rax = MOV64ri 0, debug-location !13
    $rbx = MOV64ri 0, debug-location !13
    DBG_VALUE_LIST !12, !DIExpression(), $rax, $rbx, debug-location !13
    ; CHECK: DBG_VALUE_LIST

  bb.1:
    liveins: $rax

    ; CHECK-LABEL: bb.1:
    ; Earlier DBG_VALUE_LIST should not be propagated here, would be caught
    ; by implicit check not on FileCheck cmdline.

    DBG_VALUE $rax, $noreg, !12, !DIExpression(), debug-location !13
    ; CHECK: DBG_VALUE
    $rbx = MOV64ri 0, debug-location !13
    DBG_VALUE_LIST !12, !DIExpression(), $rax, $rbx, debug-location !13
    ; CHECK: DBG_VALUE_LIST
    $rbx = COPY killed $rax, debug-location !13
    $rax = MOV64ri 0, debug-location !13
    ; This clobber of $rax might cause LDV to re-issue a DBG_VALUE stating the
    ; variable location as $rbx. However, the preceeding DBG_VALUE_LIST should
    ; terminate the earlier location.
    RET64 implicit $rbx, debug-location !13

...