Revert "[DWARF] Fix debug info generation for function static variables, typedefs, and records"

Caused PR24008

This reverts commit 37cb5f1c2db9f42d29f26b215585f56bb64ae4f5.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241176 91177308-0d34-0410-b5e6-96231b3b80d8

8 files changed, 35 insertions, 194 deletions

diff --git a/include/llvm/ADT/iterator_range.h b/include/llvm/ADT/iterator_range.h
index b266b95aba0..523a86f02e0 100644
--- a/include/llvm/ADT/iterator_range.h
+++ b/include/llvm/ADT/iterator_range.h
@@ -53,7 +53,4 @@ template <typename T> iterator_range<T> make_range(std::pair<T, T> p) {
 }
 }
 
-template <typename R>
-bool empty(const R& r) { return begin(r) == end(r); }
-
 #endif
diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index 86389f89783..fc54a2925be 100644
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -101,7 +101,7 @@ static const ConstantExpr *getMergedGlobalExpr(const Value *V) {
 
 /// getOrCreateGlobalVariableDIE - get or create global variable DIE.
 DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
-  const DIGlobalVariable *GV, DIE *ContextDIE) {
+    const DIGlobalVariable *GV) {
   // Check for pre-existence.
   if (DIE *Die = getDIE(GV))
     return Die;
@@ -113,8 +113,7 @@ DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
 
   // Construct the context before querying for the existence of the DIE in
   // case such construction creates the DIE.
-  if (ContextDIE == nullptr)
-    ContextDIE = getOrCreateContextDIE(GVContext);
+  DIE *ContextDIE = getOrCreateContextDIE(GVContext);
 
   // Add to map.
   DIE *VariableDIE = &createAndAddDIE(GV->getTag(), *ContextDIE, GV);
@@ -336,16 +335,17 @@ void DwarfCompileUnit::constructScopeDIE(
     // null and the children will be added to the scope DIE.
     createScopeChildrenDIE(Scope, Children, &ChildScopeCount);
 
-
-    DwarfDebug::LocalDeclMapRange LocalDeclNodeRangeForScope(nullptr, nullptr);
-    // Skip local decls in gmlt-like data.
-    if (!includeMinimalInlineScopes())
-      LocalDeclNodeRangeForScope = DD->findLocalDeclNodesForScope(DS);
+    // Skip imported directives in gmlt-like data.
+    if (!includeMinimalInlineScopes()) {
+      // There is no need to emit empty lexical block DIE.
+      for (const auto &E : DD->findImportedEntitiesForScope(DS))
+        Children.push_back(
+            constructImportedEntityDIE(cast<DIImportedEntity>(E.second)));
+    }
 
     // If there are only other scopes as children, put them directly in the
     // parent instead, as this scope would serve no purpose.
-    if (Children.size() == ChildScopeCount &&
-        empty(LocalDeclNodeRangeForScope)) {
+    if (Children.size() == ChildScopeCount) {
       FinalChildren.insert(FinalChildren.end(),
                            std::make_move_iterator(Children.begin()),
                            std::make_move_iterator(Children.end()));
@@ -353,15 +353,6 @@ void DwarfCompileUnit::constructScopeDIE(
     }
     ScopeDIE = constructLexicalScopeDIE(Scope);
     assert(ScopeDIE && "Scope DIE should not be null.");
-
-    for (const auto &DI : LocalDeclNodeRangeForScope) {
-      if (auto *IE = dyn_cast<DIImportedEntity>(DI.second))
-        Children.push_back(constructImportedEntityDIE(IE));
-      else if (auto *GV = dyn_cast<DIGlobalVariable>(DI.second))
-        getOrCreateGlobalVariableDIE(GV, ScopeDIE);
-      else if (auto *RT = dyn_cast<DIType>(DI.second))
-        getOrCreateTypeDIE(RT, ScopeDIE);
-    }
   }
 
   // Add children
diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
index 132b06885a3..509c9432bcb 100644
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
@@ -77,11 +77,8 @@ public:
   /// Apply the DW_AT_stmt_list from this compile unit to the specified DIE.
   void applyStmtList(DIE &D);
 
-  /// Get or create global variable DIE.
-  /// \param GV Global Variable Node
-  /// \param ContextDIE DIE scope for GV Node, if available.
-  DIE *getOrCreateGlobalVariableDIE(const DIGlobalVariable *GV,
-                                    DIE *ContextDIE = nullptr);
+  /// getOrCreateGlobalVariableDIE - get or create global variable DIE.
+  DIE *getOrCreateGlobalVariableDIE(const DIGlobalVariable *GV);
 
   /// addLabelAddress - Add a dwarf label attribute data and value using
   /// either DW_FORM_addr or DW_FORM_GNU_addr_index.
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 363311e8c9e..7d03a3930d7 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -449,14 +449,14 @@ void DwarfDebug::beginModule() {
     auto *CUNode = cast<DICompileUnit>(N);
     DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
     for (auto *IE : CUNode->getImportedEntities())
-      ScopesWithLocalDeclNodes.push_back(std::make_pair(IE->getScope(), IE));
-    for (auto *GV : CUNode->getGlobalVariables()) {
-      auto *Context = GV->getScope();
-      if (Context && isa<DILexicalBlockBase>(Context))
-        ScopesWithLocalDeclNodes.push_back(std::make_pair(Context, GV));
-      else
-        CU.getOrCreateGlobalVariableDIE(GV);
-    }
+      ScopesWithImportedEntities.push_back(std::make_pair(IE->getScope(), IE));
+    // Stable sort to preserve the order of appearance of imported entities.
+    // This is to avoid out-of-order processing of interdependent declarations
+    // within the same scope, e.g. { namespace A = base; namespace B = A; }
+    std::stable_sort(ScopesWithImportedEntities.begin(),
+                     ScopesWithImportedEntities.end(), less_first());
+    for (auto *GV : CUNode->getGlobalVariables())
+      CU.getOrCreateGlobalVariableDIE(GV);
     for (auto *SP : CUNode->getSubprograms())
       SPMap.insert(std::make_pair(SP, &CU));
     for (auto *Ty : CUNode->getEnumTypes()) {
@@ -467,23 +467,12 @@ void DwarfDebug::beginModule() {
     for (auto *Ty : CUNode->getRetainedTypes()) {
       // The retained types array by design contains pointers to
       // MDNodes rather than DIRefs. Unique them here.
-      DIType *RT = cast<DIType>(resolve(Ty->getRef()));
-      auto *Context = resolve(Ty->getScope());
-      if (Context && isa<DILexicalBlockBase>(Context))
-        ScopesWithLocalDeclNodes.push_back(std::make_pair(Context, RT));
-      else
-        CU.getOrCreateTypeDIE(RT);
+      CU.getOrCreateTypeDIE(cast<DIType>(resolve(Ty->getRef())));
     }
     // Emit imported_modules last so that the relevant context is already
     // available.
     for (auto *IE : CUNode->getImportedEntities())
       constructAndAddImportedEntityDIE(CU, IE);
-
-    // Stable sort to preserve the order of appearance of imported entities.
-    // This is to avoid out-of-order processing of interdependent declarations
-    // within the same scope, e.g. { namespace A = base; namespace B = A; }
-    std::stable_sort(ScopesWithLocalDeclNodes.begin(),
-                     ScopesWithLocalDeclNodes.end(), less_first());
   }
 
   // Tell MMI that we have debug info.
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h
index 3a583e71c4c..1c3e2aec64a 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -278,10 +278,13 @@ class DwarfDebug : public AsmPrinterHandler {
   // Holder for the file specific debug information.
   DwarfFile InfoHolder;
 
-  // Holder for local declaration DI nodes per scope.
+  // Holders for the various debug information flags that we might need to
+  // have exposed. See accessor functions below for description.
+
+  // Holder for imported entities.
   typedef SmallVector<std::pair<const MDNode *, const MDNode *>, 32>
-  LocalDeclMap;
-  LocalDeclMap ScopesWithLocalDeclNodes;
+  ImportedEntityMap;
+  ImportedEntityMap ScopesWithImportedEntities;
 
   // Map from MDNodes for user-defined types to the type units that describe
   // them.
@@ -616,12 +619,10 @@ public:
 
   const MachineFunction *getCurrentFunction() const { return CurFn; }
 
-  typedef iterator_range<LocalDeclMap::const_iterator> LocalDeclMapRange;
-  
-  LocalDeclMapRange findLocalDeclNodesForScope(const MDNode *Scope) const {
-    assert(DILexicalBlockBase::classof(Scope) && "Expected LexicalBlock scope");
+  iterator_range<ImportedEntityMap::const_iterator>
+  findImportedEntitiesForScope(const MDNode *Scope) const {
     return make_range(std::equal_range(
-        ScopesWithLocalDeclNodes.begin(), ScopesWithLocalDeclNodes.end(),
+        ScopesWithImportedEntities.begin(), ScopesWithImportedEntities.end(),
         std::pair<const MDNode *, const MDNode *>(Scope, nullptr),
         less_first()));
   }
diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index 6334be5f027..355582298e5 100644
--- a/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -704,7 +704,7 @@ DIE *DwarfUnit::createTypeDIE(const DICompositeType *Ty) {
   return &TyDIE;
 }
 
-DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode, DIE *ContextDIE) {
+DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
   if (!TyNode)
     return nullptr;
 
@@ -714,20 +714,17 @@ DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode, DIE *ContextDIE) {
 
   // DW_TAG_restrict_type is not supported in DWARF2
   if (Ty->getTag() == dwarf::DW_TAG_restrict_type && DD->getDwarfVersion() <= 2)
-    return getOrCreateTypeDIE(resolve(cast<DIDerivedType>(Ty)->getBaseType()),
-                              ContextDIE);
+    return getOrCreateTypeDIE(resolve(cast<DIDerivedType>(Ty)->getBaseType()));
 
   // Construct the context before querying for the existence of the DIE in case
   // such construction creates the DIE.
   auto *Context = resolve(Ty->getScope());
-  if (ContextDIE == nullptr)
-    ContextDIE = getOrCreateContextDIE(Context);
+  DIE *ContextDIE = getOrCreateContextDIE(Context);
+  assert(ContextDIE);
 
   if (DIE *TyDIE = getDIE(Ty))
     return TyDIE;
 
-  assert(ContextDIE);
-
   // Create new type.
   DIE &TyDIE = createAndAddDIE(Ty->getTag(), *ContextDIE, Ty);
 
diff --git a/lib/CodeGen/AsmPrinter/DwarfUnit.h b/lib/CodeGen/AsmPrinter/DwarfUnit.h
index 3f4809974f3..4000ae48a85 100644
--- a/lib/CodeGen/AsmPrinter/DwarfUnit.h
+++ b/lib/CodeGen/AsmPrinter/DwarfUnit.h
@@ -298,9 +298,7 @@ public:
                                  bool Minimal = false);
 
   /// \brief Find existing DIE or create new DIE for the given type.
-  /// \param N Type Node
-  /// \param ContextDIE DIE scope for N Node, if available.
-  DIE *getOrCreateTypeDIE(const MDNode *N, DIE *ContextDIE = nullptr);
+  DIE *getOrCreateTypeDIE(const MDNode *N);
 
   /// \brief Get context owner's DIE.
   DIE *createTypeDIE(const DICompositeType *Ty);
diff --git a/test/DebugInfo/X86/lexical-block-pr19238.ll b/test/DebugInfo/X86/lexical-block-pr19238.ll
deleted file mode 100644
index 81e31391294..00000000000
--- a/test/DebugInfo/X86/lexical-block-pr19238.ll
+++ /dev/null
@@ -1,129 +0,0 @@
-; RUN: llc -mtriple=x86_64-unknown-linux-gnu -filetype=obj -O0 < %s  | llvm-dwarfdump -debug-dump=info - | FileCheck %s
-
-;; This test checks the following:
-;; 1. Useless lexical block entry is not emitted
-;; 2. Function static variable, typedef, records (structure, class and union)
-;;    that are defined in lexical basic block are emitted as children to
-;;    these lexical blocks.
-;;    * For typedef and record check that both are emitted in lexical block
-;;      where they are declared and not in the one where they are used.
-;;
-;; This test was generated by running following command:
-;; clang -cc1 -O0 -g -emit-llvm foo.cpp 
-;; Where foo.cpp
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;;int foo(void) { 
-;;  {
-;;    {
-;;      struct X {
-;;        int x;
-;;      };
-;;      typedef int Y;
-;;      {
-;;        X a;
-;;        Y b;
-;;        static int c;
-;;        return a.x + b + c;
-;;      }
-;;    }
-;;  }
-;;}
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-
-
-; CHECK:      DW_TAG_subprogram
-; CHECK-NOT: DW_TAG
-; CHECK:        DW_AT_name {{.*}} "foo"
-; CHECK-NOT: NULL
-; CHECK:      DW_TAG_lexical_block
-
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:        DW_TAG_structure_type
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:          DW_AT_name {{.*}} "X"
-; CHECK:          NULL
-
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:        DW_TAG_typedef
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:          DW_AT_name {{.*}} "Y"
-
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:        DW_TAG_lexical_block
-
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:        DW_TAG_variable
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:          DW_AT_name {{.*}} "c"
-
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:        DW_TAG_variable
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:          DW_AT_name {{.*}} "a"
-
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:        DW_TAG_variable
-; CHECK-NOT: {{DW_TAG|NULL}}
-; CHECK:          DW_AT_name {{.*}} "b"
-
-; CHECK-NOT: {{DW_TAG}}
-; CHECK:        NULL
-
-
-%struct.X = type { i32 }
-
-@_ZZ3foovE1c = internal global i32 0, align 4
-
-; Function Attrs: nounwind
-define i32 @_Z3foov() #0 {
-entry:
-  %a = alloca %struct.X, align 4
-  %b = alloca i32, align 4
-  call void @llvm.dbg.declare(metadata %struct.X* %a, metadata !21, metadata !22), !dbg !23
-  call void @llvm.dbg.declare(metadata i32* %b, metadata !24, metadata !22), !dbg !25
-  %x = getelementptr inbounds %struct.X, %struct.X* %a, i32 0, i32 0, !dbg !26
-  %0 = load i32, i32* %x, align 4, !dbg !26
-  %1 = load i32, i32* %b, align 4, !dbg !26
-  %add = add nsw i32 %0, %1, !dbg !26
-  %2 = load i32, i32* @_ZZ3foovE1c, align 4, !dbg !26
-  %add1 = add nsw i32 %add, %2, !dbg !26
-  ret i32 %add1, !dbg !26
-}
-
-; Function Attrs: nounwind readnone
-declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
-
-attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" }
-attributes #1 = { nounwind readnone }
-
-!llvm.dbg.cu = !{!0}
-!llvm.module.flags = !{!18, !19}
-!llvm.ident = !{!20}
-
-!0 = !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.7.0 (trunk 237245)", isOptimized: false, runtimeVersion: 0, emissionKind: 1, enums: !2, retainedTypes: !3, subprograms: !14, globals: !15, imports: !2)
-!1 = !DIFile(filename: "foo.cpp", directory: "/")
-!2 = !{}
-!3 = !{!4, !13}
-!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "X", scope: !5, file: !1, line: 4, size: 32, align: 32, elements: !11)
-!5 = distinct !DILexicalBlock(scope: !6, file: !1, line: 3)
-!6 = distinct !DILexicalBlock(scope: !7, file: !1, line: 2)
-!7 = !DISubprogram(name: "foo", linkageName: "_Z3foov", scope: !1, file: !1, line: 1, type: !8, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: false, function: i32 ()* @_Z3foov, variables: !2)
-!8 = !DISubroutineType(types: !9)
-!9 = !{!10}
-!10 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
-!11 = !{!12}
-!12 = !DIDerivedType(tag: DW_TAG_member, name: "x", scope: !4, file: !1, line: 5, baseType: !10, size: 32, align: 32)
-!13 = !DIDerivedType(tag: DW_TAG_typedef, name: "Y", scope: !5, file: !1, line: 7, baseType: !10)
-!14 = !{!7}
-!15 = !{!16}
-!16 = !DIGlobalVariable(name: "c", scope: !17, file: !1, line: 11, type: !10, isLocal: true, isDefinition: true, variable: i32* @_ZZ3foovE1c)
-!17 = distinct !DILexicalBlock(scope: !5, file: !1, line: 8)
-!18 = !{i32 2, !"Dwarf Version", i32 4}
-!19 = !{i32 2, !"Debug Info Version", i32 3}
-!20 = !{!"clang version 3.7.0 (trunk 237245)"}
-!21 = !DILocalVariable(tag: DW_TAG_auto_variable, name: "a", scope: !17, file: !1, line: 9, type: !4)
-!22 = !DIExpression()
-!23 = !DILocation(line: 9, scope: !17)
-!24 = !DILocalVariable(tag: DW_TAG_auto_variable, name: "b", scope: !17, file: !1, line: 10, type: !13)
-!25 = !DILocation(line: 10, scope: !17)
-!26 = !DILocation(line: 12, scope: !17)