Revert "Revert "Debug Info: Using declarations/DW_TAG_imported_declaration of variables, types, and functions.""
This reverts commit r181947 (git d2990ce56a16050cac0d7937ec9919ff54c6df62 )
This addresses one of the two issues identified in r181947, ensuring
that types imported via using declarations only result in a declaration
being emitted for the type, not a definition. The second issue (emitting
using declarations that are unused) is hopefully an acceptable increase
as the real fix for this would be a bit difficult (probably at best we
could record which using directives were involved in lookups - but may
not have been the result of the lookup).
This also ensures that DW_TAG_imported_declarations (& directives) are
not emitted in line-tables-only mode as well as ensuring that typedefs
only require/emit declarations (rather than definitions) for referenced
types.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@182231 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index a270976..a8ab1c1 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -611,7 +611,7 @@
/// then emit record's fwd if debug info size reduction is enabled.
llvm::DIType CGDebugInfo::CreatePointeeType(QualType PointeeTy,
llvm::DIFile Unit) {
- if (DebugKind != CodeGenOptions::LimitedDebugInfo)
+ if (DebugKind > CodeGenOptions::LimitedDebugInfo)
return getOrCreateType(PointeeTy, Unit);
// Limit debug info for the pointee type.
@@ -735,7 +735,7 @@
llvm::DIType CGDebugInfo::CreateType(const TypedefType *Ty, llvm::DIFile Unit) {
// Typedefs are derived from some other type. If we have a typedef of a
// typedef, make sure to emit the whole chain.
- llvm::DIType Src = getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit);
+ llvm::DIType Src = CreatePointeeType(Ty->getDecl()->getUnderlyingType(), Unit);
if (!Src.Verify())
return llvm::DIType();
// We don't set size information, but do specify where the typedef was
@@ -2188,6 +2188,30 @@
return Ty;
}
+llvm::DIDescriptor CGDebugInfo::getDeclarationOrDefinition(const Decl *D) {
+ // We only need a declaration (not a definition) of the type - so use whatever
+ // we would otherwise do to get a type for a pointee. (forward declarations in
+ // limited debug info, full definitions (if the type definition is available)
+ // in unlimited debug info)
+ if (const TypeDecl *TD = dyn_cast<TypeDecl>(D)) {
+ llvm::DIFile DefUnit = getOrCreateFile(TD->getLocation());
+ return CreatePointeeType(CGM.getContext().getTypeDeclType(TD), DefUnit);
+ }
+ // Otherwise fall back to a fairly rudimentary cache of existing declarations.
+ // This doesn't handle providing declarations (for functions or variables) for
+ // entities without definitions in this TU, nor when the definition proceeds
+ // the call to this function.
+ // FIXME: This should be split out into more specific maps with support for
+ // emitting forward declarations and merging definitions with declarations,
+ // the same way as we do for types.
+ llvm::DenseMap<const Decl *, llvm::WeakVH>::iterator I =
+ DeclCache.find(D->getCanonicalDecl());
+ if (I == DeclCache.end())
+ return llvm::DIDescriptor();
+ llvm::Value *V = I->second;
+ return llvm::DIDescriptor(dyn_cast_or_null<llvm::MDNode>(V));
+}
+
/// getFunctionDeclaration - Return debug info descriptor to describe method
/// declaration for the given method definition.
llvm::DISubprogram CGDebugInfo::getFunctionDeclaration(const Decl *D) {
@@ -2359,6 +2383,8 @@
getLineNumber(CurLoc), Flags,
CGM.getLangOpts().Optimize,
Fn, TParamsArray, SPDecl);
+ if (HasDecl)
+ DeclCache.insert(std::make_pair(D->getCanonicalDecl(), llvm::WeakVH(SP)));
// Push function on region stack.
llvm::MDNode *SPN = SP;
@@ -2973,10 +2999,11 @@
LinkageName = StringRef();
llvm::DIDescriptor DContext =
getContextDescriptor(dyn_cast<Decl>(D->getDeclContext()));
- DBuilder.createStaticVariable(DContext, DeclName, LinkageName,
+ llvm::DIGlobalVariable GV = DBuilder.createStaticVariable(DContext, DeclName, LinkageName,
Unit, LineNo, getOrCreateType(T, Unit),
Var->hasInternalLinkage(), Var,
getStaticDataMemberDeclaration(D));
+ DeclCache.insert(std::make_pair(D->getCanonicalDecl(), llvm::WeakVH(GV)));
}
/// EmitGlobalVariable - Emit information about an objective-c interface.
@@ -3021,22 +3048,42 @@
// Do not use DIGlobalVariable for enums.
if (Ty.getTag() == llvm::dwarf::DW_TAG_enumeration_type)
return;
- DBuilder.createStaticVariable(Unit, Name, Name, Unit,
+ llvm::DIGlobalVariable GV = DBuilder.createStaticVariable(Unit, Name, Name, Unit,
getLineNumber(VD->getLocation()),
Ty, true, Init,
getStaticDataMemberDeclaration(VD));
+ DeclCache.insert(std::make_pair(VD->getCanonicalDecl(), llvm::WeakVH(GV)));
+}
+
+llvm::DIScope CGDebugInfo::getCurrentContextDescriptor(const Decl *D) {
+ if (!LexicalBlockStack.empty())
+ return llvm::DIScope(LexicalBlockStack.back());
+ return getContextDescriptor(D);
}
void CGDebugInfo::EmitUsingDirective(const UsingDirectiveDecl &UD) {
- llvm::DIScope Scope =
- LexicalBlockStack.empty()
- ? getContextDescriptor(cast<Decl>(UD.getDeclContext()))
- : llvm::DIScope(LexicalBlockStack.back());
+ if (CGM.getCodeGenOpts().getDebugInfo() < CodeGenOptions::LimitedDebugInfo)
+ return;
DBuilder.createImportedModule(
- Scope, getOrCreateNameSpace(UD.getNominatedNamespace()),
+ getCurrentContextDescriptor(cast<Decl>(UD.getDeclContext())),
+ getOrCreateNameSpace(UD.getNominatedNamespace()),
getLineNumber(UD.getLocation()));
}
+void CGDebugInfo::EmitUsingDecl(const UsingDecl &UD) {
+ if (CGM.getCodeGenOpts().getDebugInfo() < CodeGenOptions::LimitedDebugInfo)
+ return;
+ assert(UD.shadow_size() &&
+ "We shouldn't be codegening an invalid UsingDecl containing no decls");
+ // Emitting one decl is sufficient - debuggers can detect that this is an
+ // overloaded name & provide lookup for all the overloads.
+ const UsingShadowDecl &USD = **UD.shadow_begin();
+ if (llvm::DIDescriptor Target = getDeclarationOrDefinition(USD.getUnderlyingDecl()))
+ DBuilder.createImportedDeclaration(
+ getCurrentContextDescriptor(cast<Decl>(USD.getDeclContext())), Target,
+ getLineNumber(USD.getLocation()));
+}
+
/// getOrCreateNamesSpace - Return namespace descriptor for the given
/// namespace decl.
llvm::DINameSpace
diff --git a/lib/CodeGen/CGDebugInfo.h b/lib/CodeGen/CGDebugInfo.h
index 853ec2e..68fdbd9 100644
--- a/lib/CodeGen/CGDebugInfo.h
+++ b/lib/CodeGen/CGDebugInfo.h
@@ -36,6 +36,7 @@
class ObjCIvarDecl;
class ClassTemplateSpecializationDecl;
class GlobalDecl;
+ class UsingDecl;
namespace CodeGen {
class CodeGenModule;
@@ -96,6 +97,9 @@
llvm::DenseMap<const char *, llvm::WeakVH> DIFileCache;
llvm::DenseMap<const FunctionDecl *, llvm::WeakVH> SPCache;
+ /// \brief Cache declarations relevant to DW_TAG_imported_declarations (C++
+ /// using declarations) that aren't covered by other more specific caches.
+ llvm::DenseMap<const Decl *, llvm::WeakVH> DeclCache;
llvm::DenseMap<const NamespaceDecl *, llvm::WeakVH> NameSpaceCache;
llvm::DenseMap<const Decl *, llvm::WeakVH> StaticDataMemberCache;
@@ -270,6 +274,9 @@
/// \brief - Emit C++ using directive.
void EmitUsingDirective(const UsingDirectiveDecl &UD);
+ /// \brief - Emit C++ using declaration.
+ void EmitUsingDecl(const UsingDecl &UD);
+
/// getOrCreateRecordType - Emit record type's standalone debug info.
llvm::DIType getOrCreateRecordType(QualType Ty, SourceLocation L);
@@ -291,6 +298,8 @@
/// getContextDescriptor - Get context info for the decl.
llvm::DIScope getContextDescriptor(const Decl *Decl);
+ llvm::DIScope getCurrentContextDescriptor(const Decl *Decl);
+
/// createRecordFwdDecl - Create a forward decl for a RecordType in a given
/// context.
llvm::DIType createRecordFwdDecl(const RecordDecl *, llvm::DIDescriptor);
@@ -334,6 +343,10 @@
llvm::DIType CreateMemberType(llvm::DIFile Unit, QualType FType,
StringRef Name, uint64_t *Offset);
+ /// \brief Retrieve the DIDescriptor, if any, for the canonical form of this
+ /// declaration.
+ llvm::DIDescriptor getDeclarationOrDefinition(const Decl *D);
+
/// getFunctionDeclaration - Return debug info descriptor to describe method
/// declaration for the given method definition.
llvm::DISubprogram getFunctionDeclaration(const Decl *D);
diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index eb2b0e7..ce7a13d 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -72,14 +72,13 @@
case Decl::Block:
case Decl::Captured:
case Decl::ClassScopeFunctionSpecialization:
+ case Decl::UsingShadow:
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::Using: // using X; [C++]
- case Decl::UsingShadow:
case Decl::NamespaceAlias:
case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
case Decl::Label: // __label__ x;
@@ -89,6 +88,10 @@
// None of these decls require codegen support.
return;
+ case Decl::Using: // using X; [C++]
+ if (CGDebugInfo *DI = getDebugInfo())
+ DI->EmitUsingDecl(cast<UsingDecl>(D));
+ return;
case Decl::UsingDirective: // using namespace X; [C++]
if (CGDebugInfo *DI = getDebugInfo())
DI->EmitUsingDirective(cast<UsingDirectiveDecl>(D));