Index: include/llvm/IR/DebugInfoMetadata.h =================================================================== --- include/llvm/IR/DebugInfoMetadata.h +++ include/llvm/IR/DebugInfoMetadata.h @@ -2444,6 +2444,12 @@ SmallVectorImpl &Ops, bool StackValue = false); + /// Append the opcodes \p Ops to \p DIExpr. Unlike \ref appendToStack, the + /// returned expression is a stack value only if \p DIExpr is a stack value. + /// If \p DIExpr describes a fragment, the returned expression will describe + /// the same fragment. + static DIExpression *append(const DIExpression *Expr, ArrayRef Ops); + /// Convert \p DIExpr into a stack value if it isn't one already by appending /// DW_OP_deref if needed, and appending \p Ops to the resulting expression. /// If \p DIExpr describes a fragment, the returned expression will describe Index: lib/IR/DebugInfoMetadata.cpp =================================================================== --- lib/IR/DebugInfoMetadata.cpp +++ lib/IR/DebugInfoMetadata.cpp @@ -841,9 +841,36 @@ return DIExpression::get(Expr->getContext(), Ops); } +DIExpression *DIExpression::append(const DIExpression *Expr, + ArrayRef Ops) { + assert(Expr && !Ops.empty() && "Can't append ops to this expression"); + + // Copy Expr's current op list. + SmallVector NewOps; + for (auto Op : Expr->expr_ops()) { + // Append new opcodes before DW_OP_stack_value or DW_OP_LLVM_fragment. + if (Op.getOp() == dwarf::DW_OP_stack_value || + Op.getOp() == dwarf::DW_OP_LLVM_fragment) { + NewOps.append(Ops.begin(), Ops.end()); + Ops = None; + } + Op.appendToVector(NewOps); + } + + // Append any remaining new opcodes. + NewOps.append(Ops.begin(), Ops.end()); + return DIExpression::get(Expr->getContext(), NewOps); +} + DIExpression *DIExpression::appendToStack(const DIExpression *Expr, ArrayRef Ops) { assert(Expr && !Ops.empty() && "Can't append ops to this expression"); + assert(none_of(Ops, + [](uint64_t Op) { + return Op == dwarf::DW_OP_stack_value || + Op == dwarf::DW_OP_LLVM_fragment; + }) && + "Can't append this op"); // Append a DW_OP_deref after Expr's current op list if it's non-empty and // has no DW_OP_stack_value. @@ -851,30 +878,21 @@ // Match .* DW_OP_stack_value (DW_OP_LLVM_fragment A B)?. Optional FI = Expr->getFragmentInfo(); unsigned DropUntilStackValue = FI.hasValue() ? 3 : 0; - bool NeedsDeref = - (Expr->getNumElements() > DropUntilStackValue) && - (Expr->getElements().drop_back(DropUntilStackValue).back() != - dwarf::DW_OP_stack_value); - - // Copy Expr's current op list, add a DW_OP_deref if needed, and ensure that - // a DW_OP_stack_value is present. + ArrayRef ExprOpsBeforeFragment = + Expr->getElements().drop_back(DropUntilStackValue); + bool NeedsDeref = (Expr->getNumElements() > DropUntilStackValue) && + (ExprOpsBeforeFragment.back() != dwarf::DW_OP_stack_value); + bool NeedsStackValue = NeedsDeref || ExprOpsBeforeFragment.empty(); + + // Append a DW_OP_deref after Expr's current op list if needed, then append + // the new ops, and finally ensure that a single DW_OP_stack_value is present. SmallVector NewOps; - for (auto Op : Expr->expr_ops()) { - if (Op.getOp() == dwarf::DW_OP_stack_value || - Op.getOp() == dwarf::DW_OP_LLVM_fragment) - break; - Op.appendToVector(NewOps); - } if (NeedsDeref) NewOps.push_back(dwarf::DW_OP_deref); NewOps.append(Ops.begin(), Ops.end()); - NewOps.push_back(dwarf::DW_OP_stack_value); - - // If Expr is a fragment, make the new expression a fragment as well. - if (FI) - NewOps.append( - {dwarf::DW_OP_LLVM_fragment, FI->OffsetInBits, FI->SizeInBits}); - return DIExpression::get(Expr->getContext(), NewOps); + if (NeedsStackValue) + NewOps.push_back(dwarf::DW_OP_stack_value); + return DIExpression::append(Expr, NewOps); } Optional DIExpression::createFragmentExpression( Index: lib/Transforms/Utils/Local.cpp =================================================================== --- lib/Transforms/Utils/Local.cpp +++ lib/Transforms/Utils/Local.cpp @@ -1419,12 +1419,13 @@ } else if (LoadInst *LI = dyn_cast(U)) { ConvertDebugDeclareToDebugValue(DDI, LI, DIB); } else if (CallInst *CI = dyn_cast(U)) { - // This is a call by-value or some other instruction that - // takes a pointer to the variable. Insert a *value* - // intrinsic that describes the alloca. - DIB.insertDbgValueIntrinsic(AI, DDI->getVariable(), - DDI->getExpression(), DDI->getDebugLoc(), - CI); + // This is a call by-value or some other instruction that takes a + // pointer to the variable. Insert a *value* intrinsic that describes + // the variable by dereferencing the alloca. + auto *DerefExpr = + DIExpression::append(DDI->getExpression(), dwarf::DW_OP_deref); + DIB.insertDbgValueIntrinsic(AI, DDI->getVariable(), DerefExpr, + DDI->getDebugLoc(), CI); } } DDI->eraseFromParent(); Index: test/Transforms/InstCombine/lower-dbg-declare.ll =================================================================== --- /dev/null +++ test/Transforms/InstCombine/lower-dbg-declare.ll @@ -0,0 +1,183 @@ +; RUN: opt -instcombine < %s -S | FileCheck %s + +; This tests dbg.declare lowering for CallInst users of an alloca. The +; resulting dbg.value expressions should add a deref to the declare's expression. + +; Hand-reduced from this example (-g -Og -fsanitize=address): + +; static volatile int sink; +; struct OneElementVector { +; int Element; +; OneElementVector(int Element) : Element(Element) { sink = Element; } +; bool empty() const { return false; } +; }; +; using container = OneElementVector; +; static void escape(container &c) { sink = c.Element; } +; int main() { +; container d1 = {42}; +; while (!d1.empty()) +; escape(d1); +; return 0; +; } + +target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-apple-macosx10.13.0" + +%struct.OneElementVector = type { i32 } + +define i1 @escape(%struct.OneElementVector* %d1) { + ret i1 false +} + +; CHECK-LABEL: @main +define i32 @main() !dbg !15 { +entry: + %d1 = alloca %struct.OneElementVector, align 4 + %0 = bitcast %struct.OneElementVector* %d1 to i8*, !dbg !34 + +; CHECK: dbg.value(metadata %struct.OneElementVector* [[var:%.*]], metadata !DIExpression(DW_OP_deref)) +; CHECK-NEXT: call i1 @escape + call void @llvm.dbg.declare(metadata %struct.OneElementVector* %d1, metadata !19, metadata !DIExpression()), !dbg !35 + call i1 @escape(%struct.OneElementVector* %d1) + br label %while.cond, !dbg !37 + +while.cond: ; preds = %while.body, %entry +; CHECK: dbg.value(metadata %struct.OneElementVector* [[var]], metadata !DIExpression(DW_OP_deref)) +; CHECK-NEXT: call i1 @escape + %call = call i1 @escape(%struct.OneElementVector* %d1), !dbg !38 + %lnot = xor i1 %call, true, !dbg !39 + br i1 %lnot, label %while.body, label %while.end, !dbg !37 + +while.body: ; preds = %while.cond +; CHECK: dbg.value(metadata %struct.OneElementVector* [[var]], metadata !DIExpression(DW_OP_deref)) +; CHECK-NEXT: call i1 @escape + call i1 @escape(%struct.OneElementVector* %d1) + br label %while.cond, !dbg !37, !llvm.loop !42 + +while.end: ; preds = %while.cond + ret i32 0, !dbg !45 +} + +; CHECK-LABEL: @main2 +define i32 @main2() { +entry: + %d1 = alloca %struct.OneElementVector, align 4 + %0 = bitcast %struct.OneElementVector* %d1 to i8*, !dbg !34 + +; CHECK: dbg.value(metadata %struct.OneElementVector* [[var:%.*]], metadata !DIExpression(DW_OP_lit0, DW_OP_mul, DW_OP_deref)) +; CHECK-NEXT: call i1 @escape + call void @llvm.dbg.declare(metadata %struct.OneElementVector* %d1, metadata !19, metadata !DIExpression(DW_OP_lit0, DW_OP_mul)), !dbg !35 + call i1 @escape(%struct.OneElementVector* %d1) + br label %while.cond, !dbg !37 + +while.cond: ; preds = %while.body, %entry +; CHECK: dbg.value(metadata %struct.OneElementVector* [[var]], metadata !DIExpression(DW_OP_lit0, DW_OP_mul, DW_OP_deref)) +; CHECK-NEXT: call i1 @escape + %call = call i1 @escape(%struct.OneElementVector* %d1), !dbg !38 + %lnot = xor i1 %call, true, !dbg !39 + br i1 %lnot, label %while.body, label %while.end, !dbg !37 + +while.body: ; preds = %while.cond +; CHECK: dbg.value(metadata %struct.OneElementVector* [[var]], metadata !DIExpression(DW_OP_lit0, DW_OP_mul, DW_OP_deref)) +; CHECK-NEXT: call i1 @escape + call i1 @escape(%struct.OneElementVector* %d1) + br label %while.cond, !dbg !37, !llvm.loop !42 + +while.end: ; preds = %while.cond + ret i32 0, !dbg !45 +} + +declare void @llvm.dbg.declare(metadata, metadata, metadata) + +!llvm.dbg.cu = !{!2} +!llvm.asan.globals = !{!8} +!llvm.module.flags = !{!10, !11, !12, !13} +!llvm.ident = !{!14} + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(name: "sink", linkageName: "_ZL4sink", scope: !2, file: !3, line: 1, type: !6, isLocal: true, isDefinition: true) +!2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !3, producer: "clang version 7.0.0 (trunk 337207) (llvm/trunk 337204)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5) +!3 = !DIFile(filename: "test.cc", directory: "/Users/vsk/src/builds/llvm.org-master-RA") +!4 = !{} +!5 = !{!0} +!6 = !DIDerivedType(tag: DW_TAG_volatile_type, baseType: !7) +!7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!8 = !{} +!9 = !{!"test.cc", i32 1, i32 21} +!10 = !{i32 2, !"Dwarf Version", i32 4} +!11 = !{i32 2, !"Debug Info Version", i32 3} +!12 = !{i32 1, !"wchar_size", i32 4} +!13 = !{i32 7, !"PIC Level", i32 2} +!14 = !{!"clang version 7.0.0 (trunk 337207) (llvm/trunk 337204)"} +!15 = distinct !DISubprogram(name: "main", scope: !3, file: !3, line: 18, type: !16, isLocal: false, isDefinition: true, scopeLine: 18, flags: DIFlagPrototyped, isOptimized: true, unit: !2, retainedNodes: !18) +!16 = !DISubroutineType(types: !17) +!17 = !{!7} +!18 = !{!19} +!19 = !DILocalVariable(name: "d1", scope: !15, file: !3, line: 21, type: !20) +!20 = !DIDerivedType(tag: DW_TAG_typedef, name: "container", file: !3, line: 12, baseType: !21) +!21 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "OneElementVector", file: !3, line: 3, size: 32, flags: DIFlagTypePassByValue, elements: !22, identifier: "_ZTS16OneElementVector") +!22 = !{!23, !24, !28} +!23 = !DIDerivedType(tag: DW_TAG_member, name: "Element", scope: !21, file: !3, line: 4, baseType: !7, size: 32) +!24 = !DISubprogram(name: "OneElementVector", scope: !21, file: !3, line: 6, type: !25, isLocal: false, isDefinition: false, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: true) +!25 = !DISubroutineType(types: !26) +!26 = !{null, !27, !7} +!27 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !21, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer) +!28 = !DISubprogram(name: "empty", linkageName: "_ZNK16OneElementVector5emptyEv", scope: !21, file: !3, line: 8, type: !29, isLocal: false, isDefinition: false, scopeLine: 8, flags: DIFlagPrototyped, isOptimized: true) +!29 = !DISubroutineType(types: !30) +!30 = !{!31, !32} +!31 = !DIBasicType(name: "bool", size: 8, encoding: DW_ATE_boolean) +!32 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !33, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer) +!33 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !21) +!34 = !DILocation(line: 21, column: 3, scope: !15) +!35 = !DILocation(line: 21, column: 13, scope: !15) +!36 = !DILocation(line: 21, column: 18, scope: !15) +!37 = !DILocation(line: 22, column: 3, scope: !15) +!38 = !DILocation(line: 22, column: 14, scope: !15) +!39 = !DILocation(line: 22, column: 10, scope: !15) +!40 = !DILocation(line: 23, column: 5, scope: !41) +!41 = distinct !DILexicalBlock(scope: !15, file: !3, line: 22, column: 23) +!42 = distinct !{!42, !37, !43} +!43 = !DILocation(line: 24, column: 3, scope: !15) +!44 = !DILocation(line: 26, column: 1, scope: !15) +!45 = !DILocation(line: 25, column: 3, scope: !15) +!46 = distinct !DISubprogram(name: "OneElementVector", linkageName: "_ZN16OneElementVectorC1Ei", scope: !21, file: !3, line: 6, type: !25, isLocal: false, isDefinition: true, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !2, declaration: !24, retainedNodes: !47) +!47 = !{!48, !50} +!48 = !DILocalVariable(name: "this", arg: 1, scope: !46, type: !49, flags: DIFlagArtificial | DIFlagObjectPointer) +!49 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !21, size: 64) +!50 = !DILocalVariable(name: "Element", arg: 2, scope: !46, file: !3, line: 6, type: !7) +!51 = !DILocation(line: 0, scope: !46) +!52 = !DILocation(line: 6, column: 24, scope: !46) +!53 = !DILocation(line: 6, column: 52, scope: !46) +!54 = !DILocation(line: 6, column: 70, scope: !46) +!55 = distinct !DISubprogram(name: "empty", linkageName: "_ZNK16OneElementVector5emptyEv", scope: !21, file: !3, line: 8, type: !29, isLocal: false, isDefinition: true, scopeLine: 8, flags: DIFlagPrototyped, isOptimized: true, unit: !2, declaration: !28, retainedNodes: !56) +!56 = !{!57} +!57 = !DILocalVariable(name: "this", arg: 1, scope: !55, type: !58, flags: DIFlagArtificial | DIFlagObjectPointer) +!58 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !33, size: 64) +!59 = !DILocation(line: 0, scope: !55) +!60 = !DILocation(line: 8, column: 24, scope: !55) +!61 = distinct !DISubprogram(name: "escape", linkageName: "_ZL6escapeR16OneElementVector", scope: !3, file: !3, line: 14, type: !62, isLocal: true, isDefinition: true, scopeLine: 14, flags: DIFlagPrototyped, isOptimized: true, unit: !2, retainedNodes: !65) +!62 = !DISubroutineType(types: !63) +!63 = !{null, !64} +!64 = !DIDerivedType(tag: DW_TAG_reference_type, baseType: !20, size: 64) +!65 = !{!66} +!66 = !DILocalVariable(name: "c", arg: 1, scope: !61, file: !3, line: 14, type: !64) +!67 = !DILocation(line: 14, column: 31, scope: !61) +!68 = !DILocation(line: 15, column: 12, scope: !61) +!69 = !{!70, !71, i64 0} +!70 = !{!"_ZTS16OneElementVector", !71, i64 0} +!71 = !{!"int", !72, i64 0} +!72 = !{!"omnipotent char", !73, i64 0} +!73 = !{!"Simple C++ TBAA"} +!74 = !DILocation(line: 15, column: 8, scope: !61) +!75 = !{!71, !71, i64 0} +!76 = !DILocation(line: 16, column: 1, scope: !61) +!77 = distinct !DISubprogram(name: "OneElementVector", linkageName: "_ZN16OneElementVectorC2Ei", scope: !21, file: !3, line: 6, type: !25, isLocal: false, isDefinition: true, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !2, declaration: !24, retainedNodes: !78) +!78 = !{!79, !80} +!79 = !DILocalVariable(name: "this", arg: 1, scope: !77, type: !49, flags: DIFlagArtificial | DIFlagObjectPointer) +!80 = !DILocalVariable(name: "Element", arg: 2, scope: !77, file: !3, line: 6, type: !7) +!81 = !DILocation(line: 0, scope: !77) +!82 = !DILocation(line: 6, column: 24, scope: !77) +!83 = !DILocation(line: 6, column: 35, scope: !77) +!84 = !DILocation(line: 6, column: 59, scope: !85) +!85 = distinct !DILexicalBlock(scope: !77, file: !3, line: 6, column: 52) +!86 = !DILocation(line: 6, column: 70, scope: !77) Index: unittests/IR/MetadataTest.cpp =================================================================== --- unittests/IR/MetadataTest.cpp +++ unittests/IR/MetadataTest.cpp @@ -2111,14 +2111,20 @@ // Test DIExpression::prepend(). uint64_t Elts0[] = {dwarf::DW_OP_LLVM_fragment, 0, 32}; auto *N0 = DIExpression::get(Context, Elts0); - N0 = DIExpression::prepend(N0, true, 64, true, true); + auto *N0WithPrependedOps = DIExpression::prepend(N0, true, 64, true, true); uint64_t Elts1[] = {dwarf::DW_OP_deref, dwarf::DW_OP_plus_uconst, 64, dwarf::DW_OP_deref, dwarf::DW_OP_stack_value, dwarf::DW_OP_LLVM_fragment, 0, 32}; auto *N1 = DIExpression::get(Context, Elts1); - EXPECT_EQ(N0, N1); + EXPECT_EQ(N0WithPrependedOps, N1); + + // Test DIExpression::append(). + uint64_t Elts2[] = {dwarf::DW_OP_deref, dwarf::DW_OP_plus_uconst, 64, + dwarf::DW_OP_deref, dwarf::DW_OP_stack_value}; + auto *N2 = DIExpression::append(N0, Elts2); + EXPECT_EQ(N0WithPrependedOps, N2); } TEST_F(DIExpressionTest, isValid) {