Commit ccddca30 authored by Hans Wennborg's avatar Hans Wennborg
Browse files

Merging r367062: 


------------------------------------------------------------------------
r367062 | yhs | 2019-07-25 23:47:27 +0200 (Thu, 25 Jul 2019) | 30 lines

[BPF] fix typedef issue for offset relocation

Currently, the CO-RE offset relocation does not work
if any struct/union member or array element is a typedef.
For example,
  typedef const int arr_t[7];
  struct input {
      arr_t a;
  };
  func(...) {
       struct input *in = ...;
       ... __builtin_preserve_access_index(&in->a[1]) ...
  }
The BPF backend calculated default offset is 0 while
4 is the correct answer. Similar issues exist for struct/union
typedef's.

When getting struct/union member or array element type,
we should trace down to the type by skipping typedef
and qualifiers const/volatile as this is what clang did
to generate getelementptr instructions.
(const/volatile member type qualifiers are already
ignored by clang.)

This patch fixed this issue, for each access index,
skipping typedef and const/volatile/restrict BTF types.

Signed-off-by: default avatarYonghong Song <yhs@fb.com>

Differential Revision: https://reviews.llvm.org/D65259
------------------------------------------------------------------------

llvm-svn: 367211
parent 556a6ff5

llvm/lib/Target/BPF/BTFDebug.cpp

+33 −8
Original line number Diff line number Diff line
@@ -30,6 +30,18 @@ static const char *BTFKindStr[] = { 
#include "BTF.def"

};



static const DIType * stripQualifiers(const DIType *Ty) {

  while (const auto *DTy = dyn_cast<DIDerivedType>(Ty)) {

    unsigned Tag = DTy->getTag();

    if (Tag != dwarf::DW_TAG_typedef && Tag != dwarf::DW_TAG_const_type &&

        Tag != dwarf::DW_TAG_volatile_type && Tag != dwarf::DW_TAG_restrict_type)

      break;

    Ty = DTy->getBaseType();

  }



  return Ty;

}



/// Emit a BTF common type.

void BTFTypeBase::emitType(MCStreamer &OS) {

  OS.AddComment(std::string(BTFKindStr[Kind]) + "(id = " + std::to_string(Id) +
@@ -184,9 +196,9 @@ void BTFTypeEnum::emitType(MCStreamer &OS) { 
  }

}



BTFTypeArray::BTFTypeArray(uint32_t ElemTypeId, uint32_t ElemSize,

                           uint32_t NumElems)

    : ElemSize(ElemSize) {

BTFTypeArray::BTFTypeArray(const DIType *Ty, uint32_t ElemTypeId,

                           uint32_t ElemSize, uint32_t NumElems)

    : ElemTyNoQual(Ty), ElemSize(ElemSize) {

  Kind = BTF::BTF_KIND_ARRAY;

  BTFType.NameOff = 0;

  BTFType.Info = Kind << 24;
@@ -207,6 +219,9 @@ void BTFTypeArray::completeType(BTFDebug &BDebug) { 
  // created during initial type traversal. Just

  // retrieve that type id.

  ArrayInfo.IndexType = BDebug.getArrayIndexTypeId();



  ElemTypeNoQual = ElemTyNoQual ? BDebug.getTypeId(ElemTyNoQual)

                                : ArrayInfo.ElemType;

}



void BTFTypeArray::emitType(MCStreamer &OS) {
@@ -218,7 +233,7 @@ void BTFTypeArray::emitType(MCStreamer &OS) { 


void BTFTypeArray::getLocInfo(uint32_t Loc, uint32_t &LocOffset,

                              uint32_t &ElementTypeId) {

  ElementTypeId = ArrayInfo.ElemType;

  ElementTypeId = ElemTypeNoQual;

  LocOffset = Loc * ElemSize;

}
@@ -251,7 +266,9 @@ void BTFTypeStruct::completeType(BTFDebug &BDebug) { 
    } else {

      BTFMember.Offset = DDTy->getOffsetInBits();

    }

    BTFMember.Type = BDebug.getTypeId(DDTy->getBaseType());

    const auto *BaseTy = DDTy->getBaseType();

    BTFMember.Type = BDebug.getTypeId(BaseTy);

    MemberTypeNoQual.push_back(BDebug.getTypeId(stripQualifiers(BaseTy)));

    Members.push_back(BTFMember);

  }

}
@@ -270,7 +287,7 @@ std::string BTFTypeStruct::getName() { return STy->getName(); } 


void BTFTypeStruct::getMemberInfo(uint32_t Loc, uint32_t &MemberOffset,

                                  uint32_t &MemberType) {

  MemberType = Members[Loc].Type;

  MemberType = MemberTypeNoQual[Loc];

  MemberOffset =

      HasBitField ? Members[Loc].Offset & 0xffffff : Members[Loc].Offset;

}
@@ -492,10 +509,13 @@ void BTFDebug::visitArrayType(const DICompositeType *CTy, uint32_t &TypeId) { 
  uint32_t ElemTypeId, ElemSize;

  const DIType *ElemType = CTy->getBaseType();

  visitTypeEntry(ElemType, ElemTypeId, false, false);



  // Strip qualifiers from element type to get accurate element size.

  ElemType = stripQualifiers(ElemType);

  ElemSize = ElemType->getSizeInBits() >> 3;



  if (!CTy->getSizeInBits()) {

    auto TypeEntry = llvm::make_unique<BTFTypeArray>(ElemTypeId, 0, 0);

    auto TypeEntry = llvm::make_unique<BTFTypeArray>(ElemType, ElemTypeId, 0, 0);

    ArrayTypes.push_back(TypeEntry.get());

    ElemTypeId = addType(std::move(TypeEntry), CTy);

  } else {
@@ -507,9 +527,11 @@ void BTFDebug::visitArrayType(const DICompositeType *CTy, uint32_t &TypeId) { 
          const DISubrange *SR = cast<DISubrange>(Element);

          auto *CI = SR->getCount().dyn_cast<ConstantInt *>();

          int64_t Count = CI->getSExtValue();

          const DIType *ArrayElemTy = (I == 0) ? ElemType : nullptr;



          auto TypeEntry =

              llvm::make_unique<BTFTypeArray>(ElemTypeId, ElemSize, Count);

              llvm::make_unique<BTFTypeArray>(ArrayElemTy, ElemTypeId,

                                              ElemSize, Count);

          ArrayTypes.push_back(TypeEntry.get());

          if (I == 0)

            ElemTypeId = addType(std::move(TypeEntry), CTy);
@@ -1039,7 +1061,10 @@ void BTFDebug::generateOffsetReloc(const MachineInstr *MI, 
        Offset += LocOffset;

        PrevArrayType = nullptr;

        setTypeFromId(ElementTypeId, &PrevStructType, &PrevArrayType);

      } else {

        llvm_unreachable("Internal Error: BTF offset relocation type traversal error");

      }



      Start = End + 1;

      End = Start;

    }

llvm/lib/Target/BPF/BTFDebug.h

+5 −1
Original line number Diff line number Diff line
@@ -104,11 +104,14 @@ public: 


/// Handle array type.

class BTFTypeArray : public BTFTypeBase {

  const DIType *ElemTyNoQual;

  uint32_t ElemSize;

  struct BTF::BTFArray ArrayInfo;

  uint32_t ElemTypeNoQual;



public:

  BTFTypeArray(uint32_t ElemTypeId, uint32_t ElemSize, uint32_t NumElems);

  BTFTypeArray(const DIType *Ty, uint32_t ElemTypeId,

               uint32_t ElemSize, uint32_t NumElems);

  uint32_t getSize() { return BTFTypeBase::getSize() + BTF::BTFArraySize; }

  void completeType(BTFDebug &BDebug);

  void emitType(MCStreamer &OS);
@@ -120,6 +123,7 @@ class BTFTypeStruct : public BTFTypeBase { 
  const DICompositeType *STy;

  bool HasBitField;

  std::vector<struct BTF::BTFMember> Members;

  std::vector<uint32_t> MemberTypeNoQual;



public:

  BTFTypeStruct(const DICompositeType *STy, bool IsStruct, bool HasBitField,

llvm/test/CodeGen/BPF/CORE/offset-reloc-typedef-array.ll

0 → 100644
+97 −0
Original line number Diff line number Diff line 
; RUN: llc -march=bpfel -filetype=asm -o - %s | FileCheck %s

; RUN: llc -march=bpfeb -filetype=asm -o - %s | FileCheck %s

;

; Source code:

;   typedef const int arr_t[7];

;   typedef arr_t __arr;

;   typedef __arr _arr;

;   struct __s { _arr a; };

;   typedef struct __s s;

;   #define _(x) (__builtin_preserve_access_index(x))

;   int get_value(const void *addr);

;   int test(s *arg) {

;     return get_value(_(&arg->a[1]));

;   }

; clang -target bpf -S -O2 -g -emit-llvm test.c



%struct.__s = type { [7 x i32] }



; Function Attrs: nounwind

define dso_local i32 @test(%struct.__s* %arg) local_unnamed_addr #0 !dbg !7 {

entry:

  call void @llvm.dbg.value(metadata %struct.__s* %arg, metadata !24, metadata !DIExpression()), !dbg !25

  %0 = tail call [7 x i32]* @llvm.preserve.struct.access.index.p0a7i32.p0s_struct.__ss(%struct.__s* %arg, i32 0, i32 0), !dbg !26, !llvm.preserve.access.index !13

  %1 = tail call i32* @llvm.preserve.array.access.index.p0i32.p0a7i32([7 x i32]* %0, i32 1, i32 1), !dbg !26

  %2 = bitcast i32* %1 to i8*, !dbg !26

  %call = tail call i32 @get_value(i8* %2) #4, !dbg !27

  ret i32 %call, !dbg !28

}



; CHECK:        .cfi_startproc

; CHECK: [[RELOC:.Ltmp[0-9]+]]:

; CHECK:         r2 = 4

; CHECK:         r1 += r2

; CHECK:         call get_value



; CHECK:         .long   {{[0-9]+}}              # BTF_KIND_STRUCT(id = [[TYPE_ID:[0-9]+]])

; CHECK:         .ascii  ".text"                 # string offset=[[SEC_INDEX:[0-9]+]]

; CHECK-NEXT:    .byte   0

; CHECK:         .ascii  "0:0:1"                 # string offset=[[ACCESS_STR:[0-9]+]]

; CHECK-NEXT:    .byte   0

; CHECK:         .long   12                      # OffsetReloc

; CHECK-NEXT:    .long   [[SEC_INDEX]]           # Offset reloc section string offset=[[SEC_INDEX]]

; CHECK-NEXT:    .long   1

; CHECK-NEXT:    .long   [[RELOC]]

; CHECK-NEXT:    .long   [[TYPE_ID]]

; CHECK-NEXT:    .long   [[ACCESS_STR]]



declare dso_local i32 @get_value(i8*) local_unnamed_addr #1



; Function Attrs: nounwind readnone

declare [7 x i32]* @llvm.preserve.struct.access.index.p0a7i32.p0s_struct.__ss(%struct.__s*, i32 immarg, i32 immarg) #2



; Function Attrs: nounwind readnone

declare i32* @llvm.preserve.array.access.index.p0i32.p0a7i32([7 x i32]*, i32 immarg, i32 immarg) #2



; Function Attrs: nounwind readnone speculatable

declare void @llvm.dbg.value(metadata, metadata, metadata) #3



attributes #0 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }

attributes #1 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }

attributes #2 = { nounwind readnone }

attributes #3 = { nounwind readnone speculatable }

attributes #4 = { nounwind }



!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 10.0.0 (trunk 366831) (llvm/trunk 366867)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)

!1 = !DIFile(filename: "test.c", directory: "/tmp/home/yhs/work/tests/llvm/core-bugs")

!2 = !{}

!3 = !{i32 2, !"Dwarf Version", i32 4}

!4 = !{i32 2, !"Debug Info Version", i32 3}

!5 = !{i32 1, !"wchar_size", i32 4}

!6 = !{!"clang version 10.0.0 (trunk 366831) (llvm/trunk 366867)"}

!7 = distinct !DISubprogram(name: "test", scope: !1, file: !1, line: 8, type: !8, scopeLine: 8, flags: DIFlagPrototyped, isDefinition: true, isOptimized: true, unit: !0, retainedNodes: !23)

!8 = !DISubroutineType(types: !9)

!9 = !{!10, !11}

!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)

!11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 64)

!12 = !DIDerivedType(tag: DW_TAG_typedef, name: "s", file: !1, line: 5, baseType: !13)

!13 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "__s", file: !1, line: 4, size: 224, elements: !14)

!14 = !{!15}

!15 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !13, file: !1, line: 4, baseType: !16, size: 224)

!16 = !DIDerivedType(tag: DW_TAG_typedef, name: "_arr", file: !1, line: 3, baseType: !17)

!17 = !DIDerivedType(tag: DW_TAG_typedef, name: "__arr", file: !1, line: 2, baseType: !18)

!18 = !DIDerivedType(tag: DW_TAG_typedef, name: "arr_t", file: !1, line: 1, baseType: !19)

!19 = !DICompositeType(tag: DW_TAG_array_type, baseType: !20, size: 224, elements: !21)

!20 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !10)

!21 = !{!22}

!22 = !DISubrange(count: 7)

!23 = !{!24}

!24 = !DILocalVariable(name: "arg", arg: 1, scope: !7, file: !1, line: 8, type: !11)

!25 = !DILocation(line: 0, scope: !7)

!26 = !DILocation(line: 9, column: 20, scope: !7)

!27 = !DILocation(line: 9, column: 10, scope: !7)

!28 = !DILocation(line: 9, column: 3, scope: !7)

llvm/test/CodeGen/BPF/CORE/offset-reloc-typedef-struct.ll

0 → 100644
+90 −0
Original line number Diff line number Diff line 
; RUN: llc -march=bpfel -filetype=asm -o - %s | FileCheck %s

; RUN: llc -march=bpfeb -filetype=asm -o - %s | FileCheck %s

;

; Source code:

;   typedef int _int;

;   typedef _int __int;

;   struct __s { __int a; __int b; };

;   typedef struct __s _s;

;   typedef _s s;

;   #define _(x) (__builtin_preserve_access_index(x))

;   int get_value(const void *addr);

;   int test(s *arg) {

;     return get_value(_(&arg->b));

;   }

; clang -target bpf -S -O2 -g -emit-llvm test.c



%struct.__s = type { i32, i32 }



; Function Attrs: nounwind

define dso_local i32 @test(%struct.__s* %arg) local_unnamed_addr #0 !dbg !7 {

entry:

  call void @llvm.dbg.value(metadata %struct.__s* %arg, metadata !21, metadata !DIExpression()), !dbg !22

  %0 = tail call i32* @llvm.preserve.struct.access.index.p0i32.p0s_struct.__ss(%struct.__s* %arg, i32 1, i32 1), !dbg !23, !llvm.preserve.access.index !14

  %1 = bitcast i32* %0 to i8*, !dbg !23

  %call = tail call i32 @get_value(i8* %1) #4, !dbg !24

  ret i32 %call, !dbg !25

}



; CHECK:        .cfi_startproc

; CHECK:        [[RELOC:.Ltmp[0-9]+]]:

; CHECK:        r2 = 4

; CHECK:        r1 += r2

; CHECK:        call get_value



; CHECK:        .long   {{[0-9]+}}              # BTF_KIND_STRUCT(id = [[TYPE_ID:[0-9]+]])

; CHECK:        .ascii  ".text"                 # string offset=[[SEC_STR:[0-9]+]]

; CHECK-NEXT:   .byte   0

; CHECK:        .ascii  "0:1"                   # string offset=[[ACCESS_STR:[0-9]+]]

; CHECK-NEXT:   .byte   0

; CHECK:        .long   12                      # OffsetReloc

; CHECK-NEXT:   .long   [[SEC_STR]]             # Offset reloc section string offset={{[0-9]+}}

; CHECK-NEXT:   .long   1

; CHECK-NEXT:   .long   [[RELOC]]

; CHECK-NEXT:   .long   [[TYPE_ID]]

; CHECK-NEXT:   .long   [[ACCESS_STR]]



declare dso_local i32 @get_value(i8*) local_unnamed_addr #1



; Function Attrs: nounwind readnone

declare i32* @llvm.preserve.struct.access.index.p0i32.p0s_struct.__ss(%struct.__s*, i32 immarg, i32 immarg) #2



; Function Attrs: nounwind readnone speculatable

declare void @llvm.dbg.value(metadata, metadata, metadata) #3



attributes #0 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }

attributes #1 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }

attributes #2 = { nounwind readnone }

attributes #3 = { nounwind readnone speculatable }

attributes #4 = { nounwind }



!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 10.0.0 (trunk 366831) (llvm/trunk 366867)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)

!1 = !DIFile(filename: "test.c", directory: "/tmp/home/yhs/work/tests/llvm/core-bugs")

!2 = !{}

!3 = !{i32 2, !"Dwarf Version", i32 4}

!4 = !{i32 2, !"Debug Info Version", i32 3}

!5 = !{i32 1, !"wchar_size", i32 4}

!6 = !{!"clang version 10.0.0 (trunk 366831) (llvm/trunk 366867)"}

!7 = distinct !DISubprogram(name: "test", scope: !1, file: !1, line: 8, type: !8, scopeLine: 8, flags: DIFlagPrototyped, isDefinition: true, isOptimized: true, unit: !0, retainedNodes: !20)

!8 = !DISubroutineType(types: !9)

!9 = !{!10, !11}

!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)

!11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 64)

!12 = !DIDerivedType(tag: DW_TAG_typedef, name: "s", file: !1, line: 5, baseType: !13)

!13 = !DIDerivedType(tag: DW_TAG_typedef, name: "_s", file: !1, line: 4, baseType: !14)

!14 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "__s", file: !1, line: 3, size: 64, elements: !15)

!15 = !{!16, !19}

!16 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !14, file: !1, line: 3, baseType: !17, size: 32)

!17 = !DIDerivedType(tag: DW_TAG_typedef, name: "__int", file: !1, line: 2, baseType: !18)

!18 = !DIDerivedType(tag: DW_TAG_typedef, name: "_int", file: !1, line: 1, baseType: !10)

!19 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !14, file: !1, line: 3, baseType: !17, size: 32, offset: 32)

!20 = !{!21}

!21 = !DILocalVariable(name: "arg", arg: 1, scope: !7, file: !1, line: 8, type: !11)

!22 = !DILocation(line: 0, scope: !7)

!23 = !DILocation(line: 9, column: 20, scope: !7)

!24 = !DILocation(line: 9, column: 10, scope: !7)

!25 = !DILocation(line: 9, column: 3, scope: !7)

llvm/test/CodeGen/BPF/CORE/offset-reloc-typedef-union.ll

0 → 100644
+90 −0
Original line number Diff line number Diff line 
; RUN: llc -march=bpfel -filetype=asm -o - %s | FileCheck %s

; RUN: llc -march=bpfeb -filetype=asm -o - %s | FileCheck %s

;

; Source code:

;   typedef int _int;

;   typedef _int __int;

;   union __s { __int a; __int b; };

;   typedef union __s _s;

;   typedef _s s;

;   #define _(x) (__builtin_preserve_access_index(x))

;   int get_value(const void *addr);

;   int test(s *arg) {

;     return get_value(_(&arg->b));

;   }

; clang -target bpf -S -O2 -g -emit-llvm test.c



%union.__s = type { i32 }



; Function Attrs: nounwind

define dso_local i32 @test(%union.__s* %arg) local_unnamed_addr #0 !dbg !7 {

entry:

  call void @llvm.dbg.value(metadata %union.__s* %arg, metadata !21, metadata !DIExpression()), !dbg !22

  %0 = tail call %union.__s* @llvm.preserve.union.access.index.p0s_union.__ss.p0s_union.__ss(%union.__s* %arg, i32 1), !dbg !23, !llvm.preserve.access.index !14

  %1 = bitcast %union.__s* %0 to i8*, !dbg !23

  %call = tail call i32 @get_value(i8* %1) #4, !dbg !24

  ret i32 %call, !dbg !25

}



; CHECK:        .cfi_startproc

; CHECK: [[RELOC:.Ltmp[0-9]+]]:

; CHECK:         r2 = 0

; CHECK:         r1 += r2

; CHECK:         call get_value



; CHECK:         .long   {{[0-9]+}}              # BTF_KIND_UNION(id = [[TYPE_ID:[0-9]+]])

; CHECK:         .ascii  ".text"                 # string offset=[[SEC_INDEX:[0-9]+]]

; CHECK-NEXT:    .byte   0

; CHECK:         .ascii  "0:1"                   # string offset=[[ACCESS_STR:[0-9]+]]

; CHECK-NEXT:    .byte   0

; CHECK:         .long   12                      # OffsetReloc

; CHECK-NEXT:    .long   [[SEC_INDEX]]           # Offset reloc section string offset=[[SEC_INDEX]]

; CHECK-NEXT:    .long   1

; CHECK-NEXT:    .long   [[RELOC]]

; CHECK-NEXT:    .long   [[TYPE_ID]]

; CHECK-NEXT:    .long   [[ACCESS_STR]]



declare dso_local i32 @get_value(i8*) local_unnamed_addr #1



; Function Attrs: nounwind readnone

declare %union.__s* @llvm.preserve.union.access.index.p0s_union.__ss.p0s_union.__ss(%union.__s*, i32 immarg) #2



; Function Attrs: nounwind readnone speculatable

declare void @llvm.dbg.value(metadata, metadata, metadata) #3



attributes #0 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }

attributes #1 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }

attributes #2 = { nounwind readnone }

attributes #3 = { nounwind readnone speculatable }

attributes #4 = { nounwind }



!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 10.0.0 (trunk 366831) (llvm/trunk 366867)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)

!1 = !DIFile(filename: "test.c", directory: "/tmp/home/yhs/work/tests/llvm/core-bugs")

!2 = !{}

!3 = !{i32 2, !"Dwarf Version", i32 4}

!4 = !{i32 2, !"Debug Info Version", i32 3}

!5 = !{i32 1, !"wchar_size", i32 4}

!6 = !{!"clang version 10.0.0 (trunk 366831) (llvm/trunk 366867)"}

!7 = distinct !DISubprogram(name: "test", scope: !1, file: !1, line: 8, type: !8, scopeLine: 8, flags: DIFlagPrototyped, isDefinition: true, isOptimized: true, unit: !0, retainedNodes: !20)

!8 = !DISubroutineType(types: !9)

!9 = !{!10, !11}

!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)

!11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 64)

!12 = !DIDerivedType(tag: DW_TAG_typedef, name: "s", file: !1, line: 5, baseType: !13)

!13 = !DIDerivedType(tag: DW_TAG_typedef, name: "_s", file: !1, line: 4, baseType: !14)

!14 = distinct !DICompositeType(tag: DW_TAG_union_type, name: "__s", file: !1, line: 3, size: 32, elements: !15)

!15 = !{!16, !19}

!16 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !14, file: !1, line: 3, baseType: !17, size: 32)

!17 = !DIDerivedType(tag: DW_TAG_typedef, name: "__int", file: !1, line: 2, baseType: !18)

!18 = !DIDerivedType(tag: DW_TAG_typedef, name: "_int", file: !1, line: 1, baseType: !10)

!19 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !14, file: !1, line: 3, baseType: !17, size: 32)

!20 = !{!21}

!21 = !DILocalVariable(name: "arg", arg: 1, scope: !7, file: !1, line: 8, type: !11)

!22 = !DILocation(line: 0, scope: !7)

!23 = !DILocation(line: 9, column: 20, scope: !7)

!24 = !DILocation(line: 9, column: 10, scope: !7)

!25 = !DILocation(line: 9, column: 3, scope: !7)