From fff6a1b0f1fe57b46379001db75952d2a06eab1f Mon Sep 17 00:00:00 2001 From: Leonard Chan Date: Tue, 28 Jan 2020 12:30:33 -0800 Subject: [PATCH] [SafeStack][DebugInfo] Insert DW_OP_deref in correct location This patch addresses the issue found in https://bugs.llvm.org/show_bug.cgi?id=44585 where a DW_OP_deref was placed at the end of a dwarf expression, resulting in corrupt symbols when debugging. Differential Revision: https://reviews.llvm.org/D73526 --- llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp | 6 +-- llvm/test/DebugInfo/COFF/types-array-advanced.ll | 51 ++++++++++-------------- llvm/test/DebugInfo/X86/safestack-byval.ll | 2 +- llvm/test/DebugInfo/X86/safestack-deref.ll | 42 +++++++++++++++++++ 4 files changed, 66 insertions(+), 35 deletions(-) create mode 100644 llvm/test/DebugInfo/X86/safestack-deref.ll diff --git a/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp b/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp index 02de072..dc78bba 100644 --- a/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/InstrEmitter.cpp @@ -754,9 +754,9 @@ InstrEmitter::EmitDbgValue(SDDbgValue *SD, // Indirect addressing is indicated by an Imm as the second parameter. if (SD->isIndirect()) - Expr = DIExpression::append(Expr, {dwarf::DW_OP_deref}); - - MIB.addReg(0U, RegState::Debug); + MIB.addImm(0U); + else + MIB.addReg(0U, RegState::Debug); MIB.addMetadata(Var); MIB.addMetadata(Expr); diff --git a/llvm/test/DebugInfo/COFF/types-array-advanced.ll b/llvm/test/DebugInfo/COFF/types-array-advanced.ll index 3aa0686..146fd93 100644 --- a/llvm/test/DebugInfo/COFF/types-array-advanced.ll +++ b/llvm/test/DebugInfo/COFF/types-array-advanced.ll @@ -51,39 +51,28 @@ ; CHECK: SizeOf: 0 ; CHECK: Name: ; CHECK: } -; CHECK: Pointer (0x1004) { -; CHECK: TypeLeafKind: LF_POINTER (0x1002) -; CHECK: PointeeType: 0x1003 -; CHECK: PtrType: Near32 (0xA) -; CHECK: PtrMode: LValueReference (0x1) -; CHECK: IsFlat: 0 -; CHECK: IsConst: 0 -; CHECK: IsVolatile: 0 -; CHECK: IsUnaligned: 0 -; CHECK: SizeOf: 0 -; CHECK: } -; CHECK: Array (0x1005) { +; CHECK: Array (0x1004) { ; CHECK: TypeLeafKind: LF_ARRAY (0x1503) ; CHECK: ElementType: char (0x70) ; CHECK: IndexType: unsigned long (0x22) ; CHECK: SizeOf: 7 ; CHECK: Name: ; CHECK: } -; CHECK: Array (0x1006) { +; CHECK: Array (0x1005) { ; CHECK: TypeLeafKind: LF_ARRAY (0x1503) -; CHECK: ElementType: 0x1005 +; CHECK: ElementType: 0x1004 ; CHECK: IndexType: unsigned long (0x22) ; CHECK: SizeOf: 35 ; CHECK: Name: ; CHECK: } -; CHECK: Array (0x1007) { +; CHECK: Array (0x1006) { ; CHECK: TypeLeafKind: LF_ARRAY (0x1503) -; CHECK: ElementType: 0x1006 +; CHECK: ElementType: 0x1005 ; CHECK: IndexType: unsigned long (0x22) ; CHECK: SizeOf: 70 ; CHECK: Name: ; CHECK: } -; CHECK: Struct (0x1008) { +; CHECK: Struct (0x1007) { ; CHECK: TypeLeafKind: LF_STRUCTURE (0x1505) ; CHECK: MemberCount: 0 ; CHECK: Properties [ (0x280) @@ -97,16 +86,16 @@ ; CHECK: Name: incomplete_struct ; CHECK: LinkageName: .?AUincomplete_struct@@ ; CHECK: } -; CHECK: Array (0x1009) { +; CHECK: Array (0x1008) { ; CHECK: TypeLeafKind: LF_ARRAY (0x1503) -; CHECK: ElementType: incomplete_struct (0x1008) +; CHECK: ElementType: incomplete_struct (0x1007) ; CHECK: IndexType: unsigned long (0x22) ; CHECK: SizeOf: 12 ; CHECK: Name: ; CHECK: } -; CHECK: Pointer (0x100A) { +; CHECK: Pointer (0x1009) { ; CHECK: TypeLeafKind: LF_POINTER (0x1002) -; CHECK: PointeeType: 0x1009 +; CHECK: PointeeType: 0x1008 ; CHECK: PtrType: Near32 (0xA) ; CHECK: PtrMode: Pointer (0x0) ; CHECK: IsFlat: 0 @@ -115,7 +104,7 @@ ; CHECK: IsUnaligned: 0 ; CHECK: SizeOf: 4 ; CHECK: } -; CHECK: FieldList (0x100B) { +; CHECK: FieldList (0x100A) { ; CHECK: TypeLeafKind: LF_FIELDLIST (0x1203) ; CHECK: DataMember { ; CHECK: TypeLeafKind: LF_MEMBER (0x150D) @@ -125,31 +114,31 @@ ; CHECK: Name: s1 ; CHECK: } ; CHECK: } -; CHECK: Struct (0x100C) { +; CHECK: Struct (0x100B) { ; CHECK: TypeLeafKind: LF_STRUCTURE (0x1505) ; CHECK: MemberCount: 1 ; CHECK: Properties [ (0x200) ; CHECK: HasUniqueName (0x200) ; CHECK: ] -; CHECK: FieldList: (0x100B) +; CHECK: FieldList: (0x100A) ; CHECK: DerivedFrom: 0x0 ; CHECK: VShape: 0x0 ; CHECK: SizeOf: 4 ; CHECK: Name: incomplete_struct ; CHECK: LinkageName: .?AUincomplete_struct@@ ; CHECK: } -; CHECK: StringId (0x100D) { +; CHECK: StringId (0x100C) { ; CHECK: TypeLeafKind: LF_STRING_ID (0x1605) ; CHECK: Id: 0x0 ; CHECK: StringData: /t.cpp ; CHECK: } -; CHECK: UdtSourceLine (0x100E) { +; CHECK: UdtSourceLine (0x100D) { ; CHECK: TypeLeafKind: LF_UDT_SRC_LINE (0x1606) -; CHECK: UDT: incomplete_struct (0x100C) -; CHECK: SourceFile: /t.cpp (0x100D) +; CHECK: UDT: incomplete_struct (0x100B) +; CHECK: SourceFile: /t.cpp (0x100C) ; CHECK: LineNumber: 4 ; CHECK: } -; CHECK: Modifier (0x100F) { +; CHECK: Modifier (0x100E) { ; CHECK: TypeLeafKind: LF_MODIFIER (0x1001) ; CHECK: ModifiedType: int (0x74) ; CHECK: Modifiers [ (0x3) @@ -157,9 +146,9 @@ ; CHECK: Volatile (0x2) ; CHECK: ] ; CHECK: } -; CHECK: Array (0x1010) { +; CHECK: Array (0x100F) { ; CHECK: TypeLeafKind: LF_ARRAY (0x1503) -; CHECK: ElementType: const volatile int (0x100F) +; CHECK: ElementType: const volatile int (0x100E) ; CHECK: IndexType: unsigned long (0x22) ; CHECK: SizeOf: 16 ; CHECK: Name: diff --git a/llvm/test/DebugInfo/X86/safestack-byval.ll b/llvm/test/DebugInfo/X86/safestack-byval.ll index 1d53908..ee09ba5 100644 --- a/llvm/test/DebugInfo/X86/safestack-byval.ll +++ b/llvm/test/DebugInfo/X86/safestack-byval.ll @@ -14,7 +14,7 @@ ; } ; CHECK: ![[ZZZ:.*]] = !DILocalVariable(name: "zzz", -; CHECK: DBG_VALUE {{.*}} ![[ZZZ]], !DIExpression(DW_OP_constu, 400, DW_OP_minus, DW_OP_deref) +; CHECK: DBG_VALUE {{.*}} ![[ZZZ]], !DIExpression(DW_OP_constu, 400, DW_OP_minus) %struct.S = type { [100 x i32] } diff --git a/llvm/test/DebugInfo/X86/safestack-deref.ll b/llvm/test/DebugInfo/X86/safestack-deref.ll new file mode 100644 index 0000000..6a13dbc --- /dev/null +++ b/llvm/test/DebugInfo/X86/safestack-deref.ll @@ -0,0 +1,42 @@ +; This test prevents a regression of PR44585 where the DW_OP_deref is incorrectly placed at the end of the expression chain. + +; RUN: llc -O0 -mtriple=x86_64-unknown-linux-gnu -filetype=obj %s -o - | llvm-dwarfdump - --name=value | FileCheck %s +; REQUIRES: object-emission + +; CHECK: DW_TAG_variable +; CHECK-NEXT: DW_AT_location +; CHECK-NEXT: DW_OP_breg{{[0-9]+}} R{{[0-9A-Z]+}}-8 +; CHECK-NEXT: DW_OP_breg{{[0-9]+}} R{{[0-9A-Z]+}}+8, DW_OP_deref, DW_OP_lit8, DW_OP_minus +; CHECK-NEXT: DW_AT_name ("value") + +define dso_local void @_Z4funcv() safestack !dbg !7 { + %1 = alloca i8, align 8 + call void @llvm.dbg.declare(metadata i8* %1, metadata !11, metadata !DIExpression()), !dbg !22 + call void @extern_func(i8* %1), !dbg !22 + ret void +} +declare void @llvm.dbg.declare(metadata, metadata, metadata) +declare void @extern_func(i8* %0) + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!4} + +!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, emissionKind: FullDebug) +!1 = !DIFile(filename: "/tmp/test3.cpp", directory: "") +!4 = !{i32 2, !"Debug Info Version", i32 3} +!7 = distinct !DISubprogram(name: "func", linkageName: "_Z4funcv", scope: !8, file: !8, line: 7, type: !9, scopeLine: 7, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0) +!8 = !DIFile(filename: "/tmp/test3.cpp", directory: "") +!9 = !DISubroutineType(types: !10) +!10 = !{null} +!11 = !DILocalVariable(name: "value", scope: !7, file: !8, line: 8, type: !12) +!12 = distinct !DICompositeType(tag: DW_TAG_class_type, name: "A", file: !8, line: 1, size: 64, flags: DIFlagTypePassByValue | DIFlagNonTrivial, elements: !13, identifier: "_ZTS1A") +!13 = !{!14, !18} +!14 = !DIDerivedType(tag: DW_TAG_member, name: "c", scope: !12, file: !8, line: 4, baseType: !15, size: 64, flags: DIFlagPublic) +!15 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !16, size: 64) +!16 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !17) +!17 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char) +!18 = !DISubprogram(name: "A", scope: !12, file: !8, line: 3, type: !19, scopeLine: 3, flags: DIFlagPublic | DIFlagPrototyped, spFlags: 0) +!19 = !DISubroutineType(types: !20) +!20 = !{null, !21, !15} +!21 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer) +!22 = !DILocation(line: 8, column: 5, scope: !7) -- 2.7.4