Fixing a bug where debug info for a local variable gets emitted at file scope.

The patch was discussed in Phabricator. See:
http://llvm-reviews.chandlerc.com/D1281

llvm-svn: 189649

1 files changed, 30 insertions, 30 deletions

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index fe503982be3..89e20590255 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -3142,14 +3142,31 @@ CGDebugInfo::getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D) {
 }
 
 /// EmitGlobalVariable - Emit information about a global variable.
-void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
+/// \param VarOrInit either the global variable itself or the initializer
+/// \param D the global declaration
+void CGDebugInfo::EmitGlobalVariable(llvm::Value *VarOrInit,
                                      const VarDecl *D) {
   assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
   // Create global variable debug descriptor.
   llvm::DIFile Unit = getOrCreateFile(D->getLocation());
   unsigned LineNo = getLineNumber(D->getLocation());
-
-  setLocation(D->getLocation());
+  StringRef DeclName = D->getName();
+  StringRef LinkageName;
+  bool IsLocalToUnit = true;
+
+  // For deferred global variables, the current source location is usually
+  // where they are being referenced. Do not change the current source location
+  // to the place where they are declared, lest we get a bogus line table.
+  // FIXME: maybe we do not need to set the source location here at all.
+  if (llvm::GlobalVariable *Var = dyn_cast<llvm::GlobalVariable>(VarOrInit)) {
+    setLocation(D->getLocation());
+    IsLocalToUnit = Var->hasInternalLinkage();
+    if (D->getDeclContext() && !isa<FunctionDecl>(D->getDeclContext())
+        && !isa<ObjCMethodDecl>(D->getDeclContext()))
+      LinkageName = Var->getName();
+    if (LinkageName == DeclName)
+      LinkageName = StringRef();
+  }
 
   QualType T = D->getType();
   if (T->isIncompleteArrayType()) {
@@ -3161,18 +3178,11 @@ void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
     T = CGM.getContext().getConstantArrayType(ET, ConstVal,
                                               ArrayType::Normal, 0);
   }
-  StringRef DeclName = D->getName();
-  StringRef LinkageName;
-  if (D->getDeclContext() && !isa<FunctionDecl>(D->getDeclContext())
-      && !isa<ObjCMethodDecl>(D->getDeclContext()))
-    LinkageName = Var->getName();
-  if (LinkageName == DeclName)
-    LinkageName = StringRef();
   llvm::DIDescriptor DContext =
     getContextDescriptor(dyn_cast<Decl>(D->getDeclContext()));
   llvm::DIGlobalVariable GV = DBuilder.createStaticVariable(
       DContext, DeclName, LinkageName, Unit, LineNo, getOrCreateType(T, Unit),
-      Var->hasInternalLinkage(), Var,
+      IsLocalToUnit, VarOrInit,
       getOrCreateStaticDataMemberDeclarationOrNull(D));
   DeclCache.insert(std::make_pair(D->getCanonicalDecl(), llvm::WeakVH(GV)));
 }
@@ -3203,26 +3213,16 @@ void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
                                 Var->hasInternalLinkage(), Var);
 }
 
-/// EmitGlobalVariable - Emit global variable's debug info.
-void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD,
-                                     llvm::Constant *Init) {
+/// EmitEnumConstant - Emit debug info for an enumerator constant
+void CGDebugInfo::EmitEnumConstant(const EnumConstantDecl *ECD)
+{
   assert(DebugKind >= CodeGenOptions::LimitedDebugInfo);
-  // Create the descriptor for the variable.
-  llvm::DIFile Unit = getOrCreateFile(VD->getLocation());
-  StringRef Name = VD->getName();
-  llvm::DIType Ty = getOrCreateType(VD->getType(), Unit);
-  if (const EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(VD)) {
-    const EnumDecl *ED = cast<EnumDecl>(ECD->getDeclContext());
-    assert(isa<EnumType>(ED->getTypeForDecl()) && "Enum without EnumType?");
-    Ty = getOrCreateType(QualType(ED->getTypeForDecl(), 0), Unit);
-  }
-  // Do not use DIGlobalVariable for enums.
-  if (Ty.getTag() == llvm::dwarf::DW_TAG_enumeration_type)
-    return;
-  llvm::DIGlobalVariable GV = DBuilder.createStaticVariable(
-      Unit, Name, Name, Unit, getLineNumber(VD->getLocation()), Ty, true, Init,
-      getOrCreateStaticDataMemberDeclarationOrNull(cast<VarDecl>(VD)));
-  DeclCache.insert(std::make_pair(VD->getCanonicalDecl(), llvm::WeakVH(GV)));
+  llvm::DIFile Unit = getOrCreateFile(ECD->getLocation());
+  llvm::DIType Ty = getOrCreateType(ECD->getType(), Unit);
+
+  const EnumDecl *ED = cast<EnumDecl>(ECD->getDeclContext());
+  assert(isa<EnumType>(ED->getTypeForDecl()) && "Enum without EnumType?");
+  Ty = getOrCreateType(QualType(ED->getTypeForDecl(), 0), Unit);
 }
 
 llvm::DIScope CGDebugInfo::getCurrentContextDescriptor(const Decl *D) {