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.
llvm-svn: 182231
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index a270976..a8ab1c1 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/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