DebugInfo: Omit debug info for dynamic classes in TUs that do not have the vtable for that class
This reduces Clang's .dwo (fission debug info) size by 23% over
Clang+LLVM.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@188576 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index d1ee2f6..f7ea474 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -865,7 +865,7 @@
}
}
-/// CollectRecordStaticField - Helper for CollectRecordFields.
+/// Helper for CollectRecordFields.
llvm::DIDerivedType
CGDebugInfo::CreateRecordStaticField(const VarDecl *Var,
llvm::DIType RecordTy) {
@@ -951,7 +951,7 @@
for (RecordDecl::decl_iterator I = record->decls_begin(),
E = record->decls_end(); I != E; ++I)
if (const VarDecl *V = dyn_cast<VarDecl>(*I))
- elements.push_back(CreateRecordStaticField(V, RecordTy));
+ elements.push_back(getOrCreateStaticDataMemberDeclaration(V, RecordTy));
else if (FieldDecl *field = dyn_cast<FieldDecl>(*I)) {
CollectRecordNormalField(field, layout.getFieldOffset(fieldNo),
tunit, elements, RecordTy);
@@ -1122,8 +1122,14 @@
if (D->isImplicit())
continue;
- if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
- EltTys.push_back(CreateCXXMemberFunction(Method, Unit, RecordTy));
+ if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
+ llvm::DenseMap<const FunctionDecl *, llvm::WeakVH>::iterator MI =
+ SPCache.find(Method->getCanonicalDecl());
+ if (MI == SPCache.end())
+ EltTys.push_back(CreateCXXMemberFunction(Method, Unit, RecordTy));
+ else
+ EltTys.push_back(MI->second);
+ }
}
}
@@ -1408,10 +1414,18 @@
}
void CGDebugInfo::completeRequiredType(const RecordDecl *RD) {
+ if (const CXXRecordDecl *CXXDecl = dyn_cast<CXXRecordDecl>(RD))
+ if (CXXDecl->isDynamicClass())
+ return;
+
QualType Ty = CGM.getContext().getRecordType(RD);
llvm::DIType T = getTypeOrNull(Ty);
- if (!T || !T.isForwardDecl())
- return;
+ if (T && T.isForwardDecl())
+ completeClassData(RD);
+}
+
+void CGDebugInfo::completeClassData(const RecordDecl *RD) {
+ QualType Ty = CGM.getContext().getRecordType(RD);
void* TyPtr = Ty.getAsOpaquePtr();
if (CompletedTypeCache.count(TyPtr))
return;
@@ -1424,14 +1438,23 @@
/// CreateType - get structure or union type.
llvm::DIType CGDebugInfo::CreateType(const RecordType *Ty, bool Declaration) {
RecordDecl *RD = Ty->getDecl();
+ const CXXRecordDecl *CXXDecl = dyn_cast<CXXRecordDecl>(RD);
// Limited debug info should only remove struct definitions that can
// safely be replaced by a forward declaration in the source code.
- if (DebugKind <= CodeGenOptions::LimitedDebugInfo && Declaration &&
- !RD->isCompleteDefinitionRequired() && CGM.getLangOpts().CPlusPlus) {
+ if ((DebugKind <= CodeGenOptions::LimitedDebugInfo && Declaration &&
+ !RD->isCompleteDefinitionRequired() && CGM.getLangOpts().CPlusPlus) ||
+ (CXXDecl && CXXDecl->hasDefinition() && CXXDecl->isDynamicClass())) {
llvm::DIDescriptor FDContext =
getContextDescriptor(cast<Decl>(RD->getDeclContext()));
llvm::DIType RetTy = getOrCreateRecordFwdDecl(RD, FDContext);
- return RetTy;
+ // FIXME: This is conservatively correct. If we return a non-forward decl
+ // that's not a full definition (such as those created by
+ // createContextChain) then getOrCreateType will record is as a complete
+ // type and we'll never record all its members. But this means we're
+ // emitting full debug info in TUs where GCC successfully emits a partial
+ // definition of the type.
+ if (RetTy.isForwardDecl())
+ return RetTy;
}
return CreateTypeDefinition(Ty);
@@ -1466,6 +1489,13 @@
// Convert all the elements.
SmallVector<llvm::Value *, 16> EltTys;
+ llvm::DIArray PrevMem = FwdDecl.getTypeArray();
+ unsigned NumElements = PrevMem.getNumElements();
+ if (NumElements == 1 && !PrevMem.getElement(0))
+ NumElements = 0;
+ EltTys.reserve(NumElements);
+ for (unsigned i = 0; i != NumElements; ++i)
+ EltTys.push_back(PrevMem.getElement(i));
// Note: The split of CXXDecl information here is intentional, the
// gdb tests will depend on a certain ordering at printout. The debug
@@ -2291,7 +2321,7 @@
llvm::DenseMap<const FunctionDecl *, llvm::WeakVH>::iterator
MI = SPCache.find(FD->getCanonicalDecl());
if (MI == SPCache.end()) {
- if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
+ if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD->getCanonicalDecl())) {
llvm::DICompositeType T(S);
llvm::DISubprogram SP = CreateCXXMemberFunction(MD, getOrCreateFile(MD->getLocation()), T);
T.addMember(SP);
@@ -2997,19 +3027,35 @@
DbgDecl->setDebugLoc(llvm::DebugLoc::get(line, column, scope));
}
-/// getStaticDataMemberDeclaration - If D is an out-of-class definition of
-/// a static data member of a class, find its corresponding in-class
-/// declaration.
-llvm::DIDerivedType CGDebugInfo::getStaticDataMemberDeclaration(const VarDecl *D) {
- if (D->isStaticDataMember()) {
- llvm::DenseMap<const Decl *, llvm::WeakVH>::iterator
- MI = StaticDataMemberCache.find(D->getCanonicalDecl());
- if (MI != StaticDataMemberCache.end())
- // Verify the info still exists.
- if (llvm::Value *V = MI->second)
- return llvm::DIDerivedType(cast<llvm::MDNode>(V));
+/// If D is an out-of-class definition of a static data member of a class, find
+/// its corresponding in-class declaration.
+llvm::DIDerivedType
+CGDebugInfo::getOrCreateStaticDataMemberDeclarationOrNull(const VarDecl *D) {
+ if (!D->isStaticDataMember())
+ return llvm::DIDerivedType();
+ llvm::DenseMap<const Decl *, llvm::WeakVH>::iterator MI =
+ StaticDataMemberCache.find(D->getCanonicalDecl());
+ if (MI != StaticDataMemberCache.end()) {
+ assert(MI->second && "Static data member declaration should still exist");
+ return llvm::DIDerivedType(cast<llvm::MDNode>(MI->second));
}
- return llvm::DIDerivedType();
+ llvm::DICompositeType Ctxt(
+ getContextDescriptor(cast<Decl>(D->getDeclContext())));
+ llvm::DIDerivedType T = CreateRecordStaticField(D, Ctxt);
+ Ctxt.addMember(T);
+ return T;
+}
+
+llvm::DIDerivedType
+CGDebugInfo::getOrCreateStaticDataMemberDeclaration(const VarDecl *D,
+ llvm::DICompositeType Ctxt) {
+ llvm::DenseMap<const Decl *, llvm::WeakVH>::iterator MI =
+ StaticDataMemberCache.find(D->getCanonicalDecl());
+ if (MI != StaticDataMemberCache.end()) {
+ assert(MI->second && "Static data member declaration should still exist");
+ return llvm::DIDerivedType(cast<llvm::MDNode>(MI->second));
+ }
+ return CreateRecordStaticField(D, Ctxt);
}
/// EmitGlobalVariable - Emit information about a global variable.
@@ -3041,11 +3087,10 @@
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,
- getStaticDataMemberDeclaration(D));
+ llvm::DIGlobalVariable GV = DBuilder.createStaticVariable(
+ DContext, DeclName, LinkageName, Unit, LineNo, getOrCreateType(T, Unit),
+ Var->hasInternalLinkage(), Var,
+ getOrCreateStaticDataMemberDeclarationOrNull(D));
DeclCache.insert(std::make_pair(D->getCanonicalDecl(), llvm::WeakVH(GV)));
}
@@ -3093,7 +3138,7 @@
return;
llvm::DIGlobalVariable GV = DBuilder.createStaticVariable(
Unit, Name, Name, Unit, getLineNumber(VD->getLocation()), Ty, true, Init,
- getStaticDataMemberDeclaration(cast<VarDecl>(VD)));
+ getOrCreateStaticDataMemberDeclarationOrNull(cast<VarDecl>(VD)));
DeclCache.insert(std::make_pair(VD->getCanonicalDecl(), llvm::WeakVH(GV)));
}