This patch adds a new Clang compiler flag "-gline-tables-only".
It reduces the amount of emitted debug information:
1) DIEs in .debug_info have types DW_TAG_compile_unit, DW_TAG_subprogram,
DW_TAG_inlined_subroutine (for opt builds) and DW_TAG_lexical_block only.
2) .debug_str contains only function names.
3) No debug data for types/namespaces/variables is emitted.
4) The data in .debug_line is enough to produce valid stack traces with
function names and line numbers.
Reviewed by Eric Christopher.
llvm-svn: 156160
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index af6e340..b3fc0a4 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -1176,6 +1176,7 @@
/// getOrCreateRecordType - Emit record type's standalone debug info.
llvm::DIType CGDebugInfo::getOrCreateRecordType(QualType RTy,
SourceLocation Loc) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
llvm::DIType T = getOrCreateType(RTy, getOrCreateFile(Loc));
return T;
}
@@ -1184,6 +1185,7 @@
/// debug info.
llvm::DIType CGDebugInfo::getOrCreateInterfaceType(QualType D,
SourceLocation Loc) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
llvm::DIType T = getOrCreateType(D, getOrCreateFile(Loc));
DBuilder.retainType(T);
return T;
@@ -2012,18 +2014,21 @@
LinkageName = CGM.getMangledName(GD);
Flags |= llvm::DIDescriptor::FlagPrototyped;
}
- if (LinkageName == Name)
+ if (LinkageName == Name ||
+ CGM.getCodeGenOpts().DebugInfo <= CodeGenOptions::DebugLineTablesOnly)
LinkageName = StringRef();
- if (const NamespaceDecl *NSDecl =
- dyn_cast_or_null<NamespaceDecl>(FD->getDeclContext()))
- FDContext = getOrCreateNameSpace(NSDecl);
- else if (const RecordDecl *RDecl =
- dyn_cast_or_null<RecordDecl>(FD->getDeclContext()))
- FDContext = getContextDescriptor(cast<Decl>(RDecl->getDeclContext()));
+ if (CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo) {
+ if (const NamespaceDecl *NSDecl =
+ dyn_cast_or_null<NamespaceDecl>(FD->getDeclContext()))
+ FDContext = getOrCreateNameSpace(NSDecl);
+ else if (const RecordDecl *RDecl =
+ dyn_cast_or_null<RecordDecl>(FD->getDeclContext()))
+ FDContext = getContextDescriptor(cast<Decl>(RDecl->getDeclContext()));
- // Collect template parameters.
- TParamsArray = CollectFunctionTemplateParams(FD, Unit);
+ // Collect template parameters.
+ TParamsArray = CollectFunctionTemplateParams(FD, Unit);
+ }
} else if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D)) {
Name = getObjCMethodName(OMD);
Flags |= llvm::DIDescriptor::FlagPrototyped;
@@ -2039,14 +2044,27 @@
if (D->isImplicit())
Flags |= llvm::DIDescriptor::FlagArtificial;
- llvm::DISubprogram SPDecl = getFunctionDeclaration(D);
- llvm::DISubprogram SP =
- DBuilder.createFunction(FDContext, Name, LinkageName, Unit,
- LineNo, getOrCreateFunctionType(D, FnType, Unit),
- Fn->hasInternalLinkage(), true/*definition*/,
- getLineNumber(CurLoc),
- Flags, CGM.getLangOpts().Optimize, Fn,
- TParamsArray, SPDecl);
+ llvm::DIType DIFnType;
+ llvm::DISubprogram SPDecl;
+ if (CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo) {
+ DIFnType = getOrCreateFunctionType(D, FnType, Unit);
+ SPDecl = getFunctionDeclaration(D);
+ } else {
+ // Create fake but valid subroutine type. Otherwise
+ // llvm::DISubprogram::Verify() would return false, and
+ // subprogram DIE will miss DW_AT_decl_file and
+ // DW_AT_decl_line fields.
+ SmallVector<llvm::Value*, 16> Elts;
+ llvm::DIArray EltTypeArray = DBuilder.getOrCreateArray(Elts);
+ DIFnType = DBuilder.createSubroutineType(Unit, EltTypeArray);
+ }
+ llvm::DISubprogram SP;
+ SP = DBuilder.createFunction(FDContext, Name, LinkageName, Unit,
+ LineNo, DIFnType,
+ Fn->hasInternalLinkage(), true/*definition*/,
+ getLineNumber(CurLoc), Flags,
+ CGM.getLangOpts().Optimize,
+ Fn, TParamsArray, SPDecl);
// Push function on region stack.
llvm::MDNode *SPN = SP;
@@ -2204,6 +2222,7 @@
void CGDebugInfo::EmitDeclare(const VarDecl *VD, unsigned Tag,
llvm::Value *Storage,
unsigned ArgNo, CGBuilderTy &Builder) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
llvm::DIFile Unit = getOrCreateFile(VD->getLocation());
@@ -2320,12 +2339,14 @@
void CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *VD,
llvm::Value *Storage,
CGBuilderTy &Builder) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
EmitDeclare(VD, llvm::dwarf::DW_TAG_auto_variable, Storage, 0, Builder);
}
void CGDebugInfo::EmitDeclareOfBlockDeclRefVariable(
const VarDecl *VD, llvm::Value *Storage, CGBuilderTy &Builder,
const CGBlockInfo &blockInfo) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
assert(!LexicalBlockStack.empty() && "Region stack mismatch, stack empty!");
if (Builder.GetInsertBlock() == 0)
@@ -2386,6 +2407,7 @@
void CGDebugInfo::EmitDeclareOfArgVariable(const VarDecl *VD, llvm::Value *AI,
unsigned ArgNo,
CGBuilderTy &Builder) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
EmitDeclare(VD, llvm::dwarf::DW_TAG_arg_variable, AI, ArgNo, Builder);
}
@@ -2402,6 +2424,7 @@
void CGDebugInfo::EmitDeclareOfBlockLiteralArgVariable(const CGBlockInfo &block,
llvm::Value *addr,
CGBuilderTy &Builder) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
ASTContext &C = CGM.getContext();
const BlockDecl *blockDecl = block.getBlockDecl();
@@ -2546,6 +2569,7 @@
/// EmitGlobalVariable - Emit information about a global variable.
void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
const VarDecl *D) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
// Create global variable debug descriptor.
llvm::DIFile Unit = getOrCreateFile(D->getLocation());
unsigned LineNo = getLineNumber(D->getLocation());
@@ -2581,6 +2605,7 @@
/// EmitGlobalVariable - Emit information about an objective-c interface.
void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
ObjCInterfaceDecl *ID) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
// Create global variable debug descriptor.
llvm::DIFile Unit = getOrCreateFile(ID->getLocation());
unsigned LineNo = getLineNumber(ID->getLocation());
@@ -2608,6 +2633,7 @@
/// EmitGlobalVariable - Emit global variable's debug info.
void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD,
llvm::Constant *Init) {
+ assert(CGM.getCodeGenOpts().DebugInfo >= CodeGenOptions::LimitedDebugInfo);
// Create the descriptor for the variable.
llvm::DIFile Unit = getOrCreateFile(VD->getLocation());
StringRef Name = VD->getName();