llvm/test/DebugInfo/X86/dbg_value_list_clobbers.mir

# RUN: llc %s --start-after=livedebugvalues -filetype=obj -o - \
# RUN:     | llvm-dwarfdump - -name locala -o - | FileCheck %s
#
# Test that clobbers between DBG_VALUE_LIST and DBG_VALUE instructions work as
# expected. Comments and test directives inline.

--- |
  target triple = "x86_64-unknown-linux-gnu"
  define dso_local i32 @fun() local_unnamed_addr !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, producer: "clang version 11.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, splitDebugInlining: false, nameTableKind: None)
  !1 = !DIFile(filename: "example.c", directory: "/")
  !2 = !{}
  !3 = !{i32 7, !"Dwarf Version", i32 4}
  !4 = !{i32 2, !"Debug Info Version", i32 3}
  !5 = !{i32 1, !"wchar_size", i32 4}
  !6 = !{!"clang version 11.0.0"}
  !8 = !DISubroutineType(types: !9)
  !9 = !{!10}
  !10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
  !11 = !{!12}
  !22 = !DISubroutineType(types: !23)
  !23 = !{!10, !10}
  ; --- Important metadata ---
  !7 = distinct !DISubprogram(name: "fun", scope: !1, file: !1, line: 2, type: !8, scopeLine: 2, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !11)
  !15 = !DILocation(line: 1, column: 1, scope: !7)
  !12 = !DILocalVariable(name: "locala", scope: !7, file: !1, line: 1, type: !10)

...
---
name:            fun
body:             |
  bb.0.entry:
    ; This test checks that we see expected location ranges for a single variable.
    ; CHECK: {{.*}} DW_TAG_variable
    ; CHECK-NEXT: DW_AT_location {{.*}}

    DBG_VALUE_LIST !12, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_stack_value), $eax, debug-location !15
    ; CHECK-NEXT: [{{.*}}): DW_OP_breg0 RAX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_stack_value

    $edi = MOV32ri 1
    DBG_VALUE_LIST !12, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_stack_value), $esi, debug-location !15
    ; CHECK-NEXT: [{{.*}}): DW_OP_breg4 RSI+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_stack_value

    $eax = MOV32ri 2
    DBG_VALUE $eax, $noreg, !12, !DIExpression(), debug-location !15
    ; CHECK-NEXT: [{{.*}}): DW_OP_reg0 RAX

    $ecx = MOV32ri 3
    DBG_VALUE_LIST !12, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_stack_value), $eax, $ecx, debug-location !15
    ; CHECK-NEXT: [{{.*}}): DW_OP_breg0 RAX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_breg2 RCX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_plus, DW_OP_stack_value

    ; Check that a reg clobber prevents identical locations merging.
    $ecx = MOV32ri 4
    $ecx = MOV32ri 5
    DBG_VALUE_LIST !12, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_stack_value), $eax, $ecx, debug-location !15
    ; CHECK-NEXT: [{{.*}}): DW_OP_breg0 RAX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_breg2 RCX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_plus, DW_OP_stack_value

    ; Check that fragments are composed correctly.
    $ecx = MOV32ri 6
    DBG_VALUE_LIST !12, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 16), $eax, debug-location !15
    DBG_VALUE_LIST !12, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_stack_value, DW_OP_LLVM_fragment, 16, 16), $ecx, debug-location !15
    ; CHECK-NEXT: [{{.*}}): DW_OP_breg0 RAX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_stack_value, DW_OP_piece 0x2, DW_OP_breg2 RCX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_stack_value, DW_OP_piece 0x2

    ; Check that fragments clobber preceeding overlap.
    $edi = MOV32ri 7
    DBG_VALUE_LIST !12, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_stack_value, DW_OP_LLVM_fragment, 16, 16), $edi, debug-location !15
    ; CHECK-NEXT: [{{.*}}): DW_OP_breg0 RAX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_stack_value, DW_OP_piece 0x2, DW_OP_breg5 RDI+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_stack_value, DW_OP_piece 0x2

    ; Check that a (non-zero-offset) fragment works.
    $ecx = MOV32ri 8
    $ecx = MOV32ri 9
    DBG_VALUE_LIST !12, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_stack_value, DW_OP_LLVM_fragment, 16, 16), $eax, $ecx, debug-location !15
    ; CHECK-NEXT: [{{.*}}): DW_OP_breg0 RAX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_stack_value, DW_OP_piece 0x2, DW_OP_breg0 RAX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_breg2 RCX+0, DW_OP_constu 0xffffffff, DW_OP_and, DW_OP_plus, DW_OP_stack_value, DW_OP_piece 0x2

    RET64 debug-location !15
...