Recommitted r263425 "Supporting all entities declared in lexical scope in LLVM debug info."

After fixing PR26942 (the fix is included in this commit).

Differential Revision: http://reviews.llvm.org/D18350

llvm-svn: 264281

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -831,15 +831,18 @@ llvm::DIType *CGDebugInfo::CreateType(const TemplateSpecializationType *Ty,
 
 llvm::DIType *CGDebugInfo::CreateType(const TypedefType *Ty,
                                       llvm::DIFile *Unit) {
+  TypedefNameDecl *TD = Ty->getDecl();
   // We don't set size information, but do specify where the typedef was
   // declared.
-  SourceLocation Loc = Ty->getDecl()->getLocation();
+  SourceLocation Loc = TD->getLocation();
+
+  llvm::DIScope *TDContext = getDeclarationLexicalScope(*TD, QualType(Ty, 0));
 
   // Typedefs are derived from some other type.
   return DBuilder.createTypedef(
       getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit),
       Ty->getDecl()->getName(), getOrCreateFile(Loc), getLineNumber(Loc),
-      getDeclContextDescriptor(Ty->getDecl()));
+      TDContext);
 }
 
 llvm::DIType *CGDebugInfo::CreateType(const FunctionType *Ty,
@@ -1472,6 +1475,23 @@ llvm::DIType *CGDebugInfo::getOrCreateStandaloneType(QualType D,
   return T;
 }
 
+void CGDebugInfo::recordDeclarationLexicalScope(const Decl &D) {
+  assert(LexicalBlockMap.find(&D) == LexicalBlockMap.end() &&
+         "D is already mapped to lexical block scope");
+  if (!LexicalBlockStack.empty())
+    LexicalBlockMap[&D] = LexicalBlockStack.back();
+}
+
+llvm::DIScope *CGDebugInfo::getDeclarationLexicalScope(const Decl &D,
+                                                       QualType Ty) {
+  auto I = LexicalBlockMap.find(&D);
+  if (I != LexicalBlockMap.end()) {
+    RetainedTypes.push_back(Ty.getAsOpaquePtr());
+    return I->second;
+  }
+  return getDeclContextDescriptor(cast<Decl>(&D));
+}
+
 void CGDebugInfo::completeType(const EnumDecl *ED) {
   if (DebugKind <= codegenoptions::DebugLineTablesOnly)
     return;
@@ -2057,7 +2077,7 @@ llvm::DIType *CGDebugInfo::CreateEnumType(const EnumType *Ty) {
     // entered into the ReplaceMap: finalize() will replace the first
     // FwdDecl with the second and then replace the second with
     // complete type.
-    llvm::DIScope *EDContext = getDeclContextDescriptor(ED);
+    llvm::DIScope *EDContext = getDeclarationLexicalScope(*ED, QualType(Ty, 0));
     llvm::DIFile *DefUnit = getOrCreateFile(ED->getLocation());
     llvm::TempDIScope TmpContext(DBuilder.createReplaceableCompositeType(
         llvm::dwarf::DW_TAG_enumeration_type, "", TheCU, DefUnit, 0));
@@ -2101,7 +2121,7 @@ llvm::DIType *CGDebugInfo::CreateTypeDefinition(const EnumType *Ty) {
 
   llvm::DIFile *DefUnit = getOrCreateFile(ED->getLocation());
   unsigned Line = getLineNumber(ED->getLocation());
-  llvm::DIScope *EnumContext = getDeclContextDescriptor(ED);
+  llvm::DIScope *EnumContext = getDeclarationLexicalScope(*ED, QualType(Ty, 0));
   llvm::DIType *ClassTy =
       ED->isFixed() ? getOrCreateType(ED->getIntegerType(), DefUnit) : nullptr;
   return DBuilder.createEnumerationType(EnumContext, ED->getName(), DefUnit,
@@ -2362,7 +2382,7 @@ llvm::DICompositeType *CGDebugInfo::CreateLimitedType(const RecordType *Ty) {
   unsigned Line = getLineNumber(RD->getLocation());
   StringRef RDName = getClassName(RD);
 
-  llvm::DIScope *RDContext = getDeclContextDescriptor(RD);
+  llvm::DIScope *RDContext = getDeclarationLexicalScope(*RD, QualType(Ty, 0));
 
   // If we ended up creating the type during the context chain construction,
   // just return that.
@@ -2509,8 +2529,15 @@ void CGDebugInfo::collectVarDeclProps(const VarDecl *VD, llvm::DIFile *&Unit,
   if (DC->isRecord())
     DC = CGM.getContext().getTranslationUnitDecl();
 
+  if (VD->isStaticLocal()) {
+    // Get context for static locals (that are technically globals) the same way
+    // we do for "local" locals -- by using current lexical block.
+    assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
+    VDContext = LexicalBlockStack.back();
+  } else {
     llvm::DIScope *Mod = getParentModuleOrNull(VD);
     VDContext = getContextDescriptor(cast<Decl>(DC), Mod ? Mod : TheCU);
+  }
 }
 
 llvm::DISubprogram *

clang/lib/CodeGen/CGDebugInfo.h

@@ -116,6 +116,11 @@ class CGDebugInfo {
 
   /// Keep track of our current nested lexical block.
   std::vector<llvm::TypedTrackingMDRef<llvm::DIScope>> LexicalBlockStack;
+
+  /// Map of AST declaration to its lexical block scope.
+  llvm::DenseMap<const Decl *, llvm::TypedTrackingMDRef<llvm::DIScope>>
+      LexicalBlockMap;
+
   llvm::DenseMap<const Decl *, llvm::TrackingMDRef> RegionMap;
   /// Keep track of LexicalBlockStack counter at the beginning of a
   /// function. This is used to pop unbalanced regions at the end of a
@@ -378,6 +383,12 @@ public:
   /// Emit an Objective-C interface type standalone debug info.
   llvm::DIType *getOrCreateInterfaceType(QualType Ty, SourceLocation Loc);
 
+  /// Map AST declaration to its lexical block scope if available.
+  void recordDeclarationLexicalScope(const Decl &D);
+
+  /// Get lexical scope of AST declaration.
+  llvm::DIScope *getDeclarationLexicalScope(const Decl &D, QualType Ty);
+
   /// Emit standalone debug info for a type.
   llvm::DIType *getOrCreateStandaloneType(QualType Ty, SourceLocation Loc);
 

clang/lib/CodeGen/CGDecl.cpp

@@ -88,10 +88,6 @@ void CodeGenFunction::EmitDecl(const Decl &D) {
   case Decl::ObjCTypeParam:
     llvm_unreachable("Declaration should not be in declstmts!");
   case Decl::Function:     // void X();
-  case Decl::Record:    // struct/union/class X;
-  case Decl::Enum:      // enum X;
-  case Decl::EnumConstant: // enum ? { X = ? }
-  case Decl::CXXRecord: // struct/union/class X; [C++]
   case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
   case Decl::Label:        // __label__ x;
   case Decl::Import:
@@ -101,6 +97,14 @@ void CodeGenFunction::EmitDecl(const Decl &D) {
     // None of these decls require codegen support.
     return;
 
+  case Decl::Record:       // struct/union/class X;
+  case Decl::Enum:         // enum X;
+  case Decl::EnumConstant: // enum ? { X = ? }
+  case Decl::CXXRecord:    // struct/union/class X; [C++]
+    if (CGDebugInfo *DI = getDebugInfo())
+      DI->recordDeclarationLexicalScope(D);
+    return;
+
   case Decl::NamespaceAlias:
     if (CGDebugInfo *DI = getDebugInfo())
       DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(D));
@@ -128,6 +132,9 @@ void CodeGenFunction::EmitDecl(const Decl &D) {
     const TypedefNameDecl &TD = cast<TypedefNameDecl>(D);
     QualType Ty = TD.getUnderlyingType();
 
+    if (CGDebugInfo *DI = getDebugInfo())
+      DI->recordDeclarationLexicalScope(D);
+
     if (Ty->isVariablyModifiedType())
       EmitVariablyModifiedType(Ty);
   }

clang/test/CodeGenCXX/debug-info-anon-union-vars.cpp

@@ -44,7 +44,12 @@ void instantiate(int x) {
   buildBytes(x);
 }
 
+// CHECK: ![[UNION:[0-9]+]] = !DICompositeType(tag: DW_TAG_union_type,
+// CHECK-NOT: name:
+// CHECK: elements
 // CHECK: [[FILE:.*]] = !DIFile(filename: "{{.*}}debug-info-anon-union-vars.cpp",
+// CHECK: !DIDerivedType(tag: DW_TAG_member, name: "i", scope: ![[UNION]],
+// CHECK: !DIDerivedType(tag: DW_TAG_member, name: "c", scope: ![[UNION]],
 // CHECK: !DIGlobalVariable(name: "c",{{.*}} file: [[FILE]], line: 6,{{.*}} isLocal: true, isDefinition: true
 // CHECK: !DIGlobalVariable(name: "d",{{.*}} file: [[FILE]], line: 6,{{.*}} isLocal: true, isDefinition: true
 // CHECK: !DIGlobalVariable(name: "a",{{.*}} file: [[FILE]], line: 6,{{.*}} isLocal: true, isDefinition: true
@@ -55,9 +60,4 @@ void instantiate(int x) {
 // CHECK: !DILocalVariable(name: "c", {{.*}}, flags: DIFlagArtificial
 // CHECK: !DILocalVariable(
 // CHECK-NOT: name:
-// CHECK: type: ![[UNION:[0-9]+]]
-// CHECK: ![[UNION]] = !DICompositeType(tag: DW_TAG_union_type,
-// CHECK-NOT: name:
-// CHECK: elements
-// CHECK: !DIDerivedType(tag: DW_TAG_member, name: "i", scope: ![[UNION]],
-// CHECK: !DIDerivedType(tag: DW_TAG_member, name: "c", scope: ![[UNION]],
+// CHECK: type: ![[UNION]]

clang/test/CodeGenCXX/debug-info-lb.cpp

@@ -0,0 +1,27 @@
+// RUN: %clang_cc1 -triple x86_64-none-linux-gnu -emit-llvm -debug-info-kind=limited %s -o - | FileCheck %s
+
+void foo() {
+  static int bar = 1;
+  {
+    struct X {};
+    typedef char Y;
+    static int bar = 0;
+    // The following basic block is intended, in order to check the case where
+    // types "X", "Y" are defined in a different scope than where they are used.
+    // They should have the scope they are defined at as their parent scope.
+    {
+      X a;
+      Y b;
+    }
+  }
+}
+
+// CHECK: !{{[0-9]+}} = !DICompositeType(tag: DW_TAG_structure_type, name: "X", scope: [[LBScope:![0-9]+]],
+// CHECK: [[LBScope]] = distinct !DILexicalBlock(scope: !{{[0-9]+}}, file: !{{[0-9]+}}, line: 5)
+
+// CHECK: [[FuncScope:![0-9]+]] = distinct !DISubprogram(name: "foo",
+
+// CHECK: !{{[0-9]+}} = !DIDerivedType(tag: DW_TAG_typedef, name: "Y", scope: [[LBScope]],
+// CHECK: !{{[0-9]+}} = !DIGlobalVariable(name: "bar", scope: [[FuncScope]], file: !{{[0-9]+}}, line: 4
+// CHECK: !{{[0-9]+}} = !DIGlobalVariable(name: "bar", scope: [[LBScope]], file: !{{[0-9]+}}, line: 8
+