From: Adrian Prantl Date: Fri, 17 Feb 2017 19:42:32 +0000 (+0000) Subject: Debug Info: Sort frame index expressions before emitting them. X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7e8d980564ddef4721213740345c03e345ad0ccb;p=llvm Debug Info: Sort frame index expressions before emitting them. This fixes PR31381, which caused an assertion and/or invalid debug info. This affects debug variables that have multiple fragments in the MMI side (i.e.: in the stack frame) table. rdar://problem/30571676 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295486 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp index d4c7ff193dc..66ac0e7271d 100644 --- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp @@ -522,22 +522,19 @@ DIE *DwarfCompileUnit::constructVariableDIEImpl(const DbgVariable &DV, } // .. else use frame index. - if (DV.getFrameIndex().empty()) + if (!DV.hasFrameIndexExprs()) return VariableDie; - auto Expr = DV.getExpression().begin(); DIELoc *Loc = new (DIEValueAllocator) DIELoc; DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc); - for (auto FI : DV.getFrameIndex()) { + for (auto &Fragment : DV.getFrameIndexExprs()) { unsigned FrameReg = 0; const TargetFrameLowering *TFI = Asm->MF->getSubtarget().getFrameLowering(); - int Offset = TFI->getFrameIndexReference(*Asm->MF, FI, FrameReg); - assert(Expr != DV.getExpression().end() && "Wrong number of expressions"); - DwarfExpr.addFragmentOffset(*Expr); + int Offset = TFI->getFrameIndexReference(*Asm->MF, Fragment.FI, FrameReg); + DwarfExpr.addFragmentOffset(Fragment.Expr); DwarfExpr.AddMachineRegIndirect(*Asm->MF->getSubtarget().getRegisterInfo(), FrameReg, Offset); - DwarfExpr.AddExpression(*Expr); - ++Expr; + DwarfExpr.AddExpression(Fragment.Expr); } addBlock(*VariableDie, dwarf::DW_AT_location, DwarfExpr.finalize()); diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp index 749957fea90..c4a5a58df5d 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp @@ -199,6 +199,15 @@ const DIType *DbgVariable::getType() const { return Ty; } +ArrayRef DbgVariable::getFrameIndexExprs() const { + std::sort(FrameIndexExprs.begin(), FrameIndexExprs.end(), + [](const FrameIndexExpr &A, const FrameIndexExpr &B) -> bool { + return A.Expr->getFragmentInfo()->OffsetInBits < + B.Expr->getFragmentInfo()->OffsetInBits; + }); + return FrameIndexExprs; +} + static const DwarfAccelTable::Atom TypeAtoms[] = { DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4), DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2), diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h index 8e95af54651..1976d9dcbb4 100644 --- a/lib/CodeGen/AsmPrinter/DwarfDebug.h +++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h @@ -54,7 +54,7 @@ class MachineModuleInfo; /// /// Variables can be created from allocas, in which case they're generated from /// the MMI table. Such variables can have multiple expressions and frame -/// indices. The \a Expr and \a FrameIndices array must match. +/// indices. /// /// Variables can be created from \c DBG_VALUE instructions. Those whose /// location changes over time use \a DebugLocListIndex, while those with a @@ -64,11 +64,16 @@ class MachineModuleInfo; class DbgVariable { const DILocalVariable *Var; /// Variable Descriptor. const DILocation *IA; /// Inlined at location. - SmallVector Expr; /// Complex address. DIE *TheDIE = nullptr; /// Variable DIE. unsigned DebugLocListIndex = ~0u; /// Offset in DebugLocs. const MachineInstr *MInsn = nullptr; /// DBG_VALUE instruction. - SmallVector FrameIndex; /// Frame index. + + struct FrameIndexExpr { + int FI; + const DIExpression *Expr; + }; + mutable SmallVector + FrameIndexExprs; /// Frame index + expression. public: /// Construct a DbgVariable. @@ -80,21 +85,18 @@ public: /// Initialize from the MMI table. void initializeMMI(const DIExpression *E, int FI) { - assert(Expr.empty() && "Already initialized?"); - assert(FrameIndex.empty() && "Already initialized?"); + assert(FrameIndexExprs.empty() && "Already initialized?"); assert(!MInsn && "Already initialized?"); assert((!E || E->isValid()) && "Expected valid expression"); assert(~FI && "Expected valid index"); - Expr.push_back(E); - FrameIndex.push_back(FI); + FrameIndexExprs.push_back({FI, E}); } /// Initialize from a DBG_VALUE instruction. void initializeDbgValue(const MachineInstr *DbgValue) { - assert(Expr.empty() && "Already initialized?"); - assert(FrameIndex.empty() && "Already initialized?"); + assert(FrameIndexExprs.empty() && "Already initialized?"); assert(!MInsn && "Already initialized?"); assert(Var == DbgValue->getDebugVariable() && "Wrong variable"); @@ -103,16 +105,15 @@ public: MInsn = DbgValue; if (auto *E = DbgValue->getDebugExpression()) if (E->getNumElements()) - Expr.push_back(E); + FrameIndexExprs.push_back({0, E}); } // Accessors. const DILocalVariable *getVariable() const { return Var; } const DILocation *getInlinedAt() const { return IA; } - ArrayRef getExpression() const { return Expr; } const DIExpression *getSingleExpression() const { - assert(MInsn && Expr.size() <= 1); - return Expr.size() ? Expr[0] : nullptr; + assert(MInsn && FrameIndexExprs.size() <= 1); + return FrameIndexExprs.size() ? FrameIndexExprs[0].Expr : nullptr; } void setDIE(DIE &D) { TheDIE = &D; } DIE *getDIE() const { return TheDIE; } @@ -120,7 +121,9 @@ public: unsigned getDebugLocListIndex() const { return DebugLocListIndex; } StringRef getName() const { return Var->getName(); } const MachineInstr *getMInsn() const { return MInsn; } - ArrayRef getFrameIndex() const { return FrameIndex; } + /// Get the FI entries, sorted by fragment offset. + ArrayRef getFrameIndexExprs() const; + bool hasFrameIndexExprs() const { return !FrameIndexExprs.empty(); } void addMMIEntry(const DbgVariable &V) { assert(DebugLocListIndex == ~0U && !MInsn && "not an MMI entry"); @@ -128,16 +131,15 @@ public: assert(V.Var == Var && "conflicting variable"); assert(V.IA == IA && "conflicting inlined-at location"); - assert(!FrameIndex.empty() && "Expected an MMI entry"); - assert(!V.FrameIndex.empty() && "Expected an MMI entry"); - assert(Expr.size() == FrameIndex.size() && "Mismatched expressions"); - assert(V.Expr.size() == V.FrameIndex.size() && "Mismatched expressions"); + assert(!FrameIndexExprs.empty() && "Expected an MMI entry"); + assert(!V.FrameIndexExprs.empty() && "Expected an MMI entry"); - Expr.append(V.Expr.begin(), V.Expr.end()); - FrameIndex.append(V.FrameIndex.begin(), V.FrameIndex.end()); - assert(all_of(Expr, [](const DIExpression *E) { - return E && E->isFragment(); - }) && "conflicting locations for variable"); + FrameIndexExprs.append(V.FrameIndexExprs.begin(), V.FrameIndexExprs.end()); + assert(all_of(FrameIndexExprs, + [](FrameIndexExpr &FIE) { + return FIE.Expr && FIE.Expr->isFragment(); + }) && + "conflicting locations for variable"); } // Translate tag to proper Dwarf tag. @@ -167,11 +169,11 @@ public: bool hasComplexAddress() const { assert(MInsn && "Expected DBG_VALUE, not MMI variable"); - assert(FrameIndex.empty() && "Expected DBG_VALUE, not MMI variable"); - assert( - (Expr.empty() || (Expr.size() == 1 && Expr.back()->getNumElements())) && - "Invalid Expr for DBG_VALUE"); - return !Expr.empty(); + assert((FrameIndexExprs.empty() || + (FrameIndexExprs.size() == 1 && + FrameIndexExprs[0].Expr->getNumElements())) && + "Invalid Expr for DBG_VALUE"); + return !FrameIndexExprs.empty(); } bool isBlockByrefVariable() const; const DIType *getType() const; diff --git a/test/DebugInfo/X86/FrameIndexExprs.ll b/test/DebugInfo/X86/FrameIndexExprs.ll new file mode 100644 index 00000000000..a964688cd97 --- /dev/null +++ b/test/DebugInfo/X86/FrameIndexExprs.ll @@ -0,0 +1,85 @@ +; PR31381: An assertion in the DWARF backend when fragments in MMI slots are +; sorted by largest offset first. +; RUN: %llc_dwarf -filetype=obj < %s | llvm-dwarfdump -debug-dump=info - | FileCheck %s +; CHECK: DW_TAG_formal_parameter +; CHECK: DW_TAG_formal_parameter +; CHECK-NEXT: DW_AT_location [DW_FORM_exprloc] (<0xa> 91 78 93 03 93 06 91 7d 93 03 ) +; fbreg -8, piece 0x00000003, piece 0x00000006, fbreg -3, piece 0x00000003 +; CHECK-NEXT: DW_AT_abstract_origin {{.*}}"p" +source_filename = "bugpoint-reduced-simplified.ll" +target triple = "x86_64-apple-darwin" + +@f = common local_unnamed_addr global i32 0, align 4, !dbg !0 +@h = common local_unnamed_addr global i32 0, align 4, !dbg !6 + +; Function Attrs: nounwind readnone +declare void @llvm.dbg.declare(metadata, metadata, metadata) #0 + +define void @fn4() local_unnamed_addr !dbg !12 { +entry: + %l1.sroa.7.i = alloca [3 x i8], align 1 + tail call void @llvm.dbg.declare(metadata [3 x i8]* %l1.sroa.7.i, metadata !15, metadata !26), !dbg !27 + %i.sroa.4.i = alloca [3 x i8], align 8 + tail call void @llvm.dbg.declare(metadata [3 x i8]* %i.sroa.4.i, metadata !15, metadata !32), !dbg !27 + %0 = load i32, i32* @h, align 4 + br label %while.body.i.i, !dbg !33 + +while.body.i.i: ; preds = %while.body.i.i, %entry + br label %while.body.i.i, !dbg !34 + +fn3.exit: ; No predecessors! + %1 = load i32, i32* @f, align 4 + %tobool.i = icmp eq i32 %1, 0 + br label %while.body.i + +while.body.i: ; preds = %if.end.i, %fn3.exit + br i1 %tobool.i, label %if.end.i, label %if.then.i + +if.then.i: ; preds = %while.body.i + br label %if.end.i + +if.end.i: ; preds = %if.then.i, %while.body.i + br label %while.body.i +} + +attributes #0 = { nounwind readnone } + +!llvm.dbg.cu = !{!2} +!llvm.module.flags = !{!9, !10, !11} + +!0 = !DIGlobalVariableExpression(var: !1) +!1 = distinct !DIGlobalVariable(name: "f", scope: !2, file: !3, line: 8, type: !8, isLocal: false, isDefinition: true) +!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5) +!3 = !DIFile(filename: "PR31381.c", directory: "/") +!4 = !{} +!5 = !{!0, !6} +!6 = !DIGlobalVariableExpression(var: !7) +!7 = distinct !DIGlobalVariable(name: "h", scope: !2, file: !3, line: 8, type: !8, isLocal: false, isDefinition: true) +!8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!9 = !{i32 2, !"Dwarf Version", i32 4} +!10 = !{i32 2, !"Debug Info Version", i32 3} +!11 = !{i32 1, !"PIC Level", i32 2} +!12 = distinct !DISubprogram(name: "fn4", scope: !3, file: !3, line: 31, type: !13, isLocal: false, isDefinition: true, scopeLine: 32, isOptimized: true, unit: !2, variables: !4) +!13 = !DISubroutineType(types: !14) +!14 = !{null} +!15 = !DILocalVariable(name: "p", arg: 1, scope: !16, file: !3, line: 19, type: !19) +!16 = distinct !DISubprogram(name: "fn2", scope: !3, file: !3, line: 19, type: !17, isLocal: false, isDefinition: true, scopeLine: 20, flags: DIFlagPrototyped, isOptimized: true, unit: !2, variables: !25) +!17 = !DISubroutineType(types: !18) +!18 = !{null, !19} +!19 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "S", file: !3, line: 1, size: 96, elements: !20) +!20 = !{!21, !23, !24} +!21 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !19, file: !3, line: 4, baseType: !22, size: 8, offset: 24) +!22 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char) +!23 = !DIDerivedType(tag: DW_TAG_member, name: "c", scope: !19, file: !3, line: 5, baseType: !8, size: 32, offset: 32) +!24 = !DIDerivedType(tag: DW_TAG_member, name: "d", scope: !19, file: !3, line: 6, baseType: !8, size: 6, offset: 64, flags: DIFlagBitField, extraData: i64 64) +!25 = !{!15} +!26 = !DIExpression(DW_OP_LLVM_fragment, 72, 24) +!27 = !DILocation(line: 19, column: 20, scope: !16, inlinedAt: !28) +!28 = distinct !DILocation(line: 27, column: 3, scope: !29, inlinedAt: !30) +!29 = distinct !DISubprogram(name: "fn3", scope: !3, file: !3, line: 24, type: !13, isLocal: false, isDefinition: true, scopeLine: 25, isOptimized: true, unit: !2, variables: !4) +!30 = distinct !DILocation(line: 34, column: 7, scope: !31) +!31 = distinct !DILexicalBlock(scope: !12, file: !3, line: 33, column: 5) +!32 = !DIExpression(DW_OP_LLVM_fragment, 0, 24) +!33 = !DILocation(line: 22, column: 9, scope: !16, inlinedAt: !28) +!34 = !DILocation(line: 21, column: 3, scope: !35, inlinedAt: !28) +!35 = !DILexicalBlockFile(scope: !16, file: !3, discriminator: 2)