swiftlang · ellishg · Sep 29, 2020 · Sep 29, 2020
diff --git a/clang/include/clang/AST/DeclObjC.h b/clang/include/clang/AST/DeclObjC.h
@@ -320,6 +320,13 @@ class ObjCMethodDecl : public NamedDecl, public DeclContext {
     return const_cast<ObjCMethodDecl*>(this)->getClassInterface();
   }
 
+  /// If this method is declared or implemented in a category, return
+  /// that category.
+  ObjCCategoryDecl *getCategory();
+  const ObjCCategoryDecl *getCategory() const {
+    return const_cast<ObjCMethodDecl*>(this)->getCategory();
+  }
+
   Selector getSelector() const { return getDeclName().getObjCSelector(); }
 
   QualType getReturnType() const { return MethodDeclType; }

diff --git a/clang/include/clang/AST/Mangle.h b/clang/include/clang/AST/Mangle.h
@@ -123,8 +123,11 @@ class MangleContext {
   void mangleBlock(const DeclContext *DC, const BlockDecl *BD,
                    raw_ostream &Out);
 
-  void mangleObjCMethodNameWithoutSize(const ObjCMethodDecl *MD, raw_ostream &);
-  void mangleObjCMethodName(const ObjCMethodDecl *MD, raw_ostream &);
+  void mangleObjCMethodName(const ObjCMethodDecl *MD, raw_ostream &OS,
+                            bool includePrefixByte = true,
+                            bool includeCategoryNamespace = true);
+  void mangleObjCMethodNameAsSourceName(const ObjCMethodDecl *MD,
+                                        raw_ostream &);
 
   virtual void mangleStaticGuardVariable(const VarDecl *D, raw_ostream &) = 0;
 

diff --git a/clang/lib/AST/DeclObjC.cpp b/clang/lib/AST/DeclObjC.cpp
@@ -1167,6 +1167,14 @@ ObjCInterfaceDecl *ObjCMethodDecl::getClassInterface() {
   llvm_unreachable("unknown method context");
 }
 
+ObjCCategoryDecl *ObjCMethodDecl::getCategory() {
+  if (auto *CD = dyn_cast<ObjCCategoryDecl>(getDeclContext()))
+    return CD;
+  if (auto *IMD = dyn_cast<ObjCCategoryImplDecl>(getDeclContext()))
+    return IMD->getCategoryDecl();
+  return nullptr;
+}
+
 SourceRange ObjCMethodDecl::getReturnTypeSourceRange() const {
   const auto *TSI = getReturnTypeSourceInfo();
   if (TSI)

diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
@@ -2492,7 +2492,7 @@ void CXXNameMangler::mangleRefQualifier(RefQualifierKind RefQualifier) {
 }
 
 void CXXNameMangler::mangleObjCMethodName(const ObjCMethodDecl *MD) {
-  Context.mangleObjCMethodName(MD, Out);
+  Context.mangleObjCMethodNameAsSourceName(MD, Out);
 }
 
 static bool isTypeSubstitutable(Qualifiers Quals, const Type *Ty,

diff --git a/clang/lib/AST/Mangle.cpp b/clang/lib/AST/Mangle.cpp
@@ -175,7 +175,7 @@ void MangleContext::mangleName(GlobalDecl GD, raw_ostream &Out) {
   const TargetInfo &TI = Context.getTargetInfo();
   if (CC == CCM_Other || (MCXX && TI.getCXXABI() == TargetCXXABI::Microsoft)) {
     if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D))
-      mangleObjCMethodName(OMD, Out);
+      mangleObjCMethodNameAsSourceName(OMD, Out);
     else
       mangleCXXName(GD, Out);
     return;
@@ -192,7 +192,7 @@ void MangleContext::mangleName(GlobalDecl GD, raw_ostream &Out) {
   if (!MCXX)
     Out << D->getIdentifier()->getName();
   else if (const ObjCMethodDecl *OMD = dyn_cast<ObjCMethodDecl>(D))
-    mangleObjCMethodName(OMD, Out);
+    mangleObjCMethodNameAsSourceName(OMD, Out);
   else
     mangleCXXName(GD, Out);
 
@@ -275,7 +275,7 @@ void MangleContext::mangleBlock(const DeclContext *DC, const BlockDecl *BD,
   SmallString<64> Buffer;
   llvm::raw_svector_ostream Stream(Buffer);
   if (const ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(DC)) {
-    mangleObjCMethodName(Method, Stream);
+    mangleObjCMethodNameAsSourceName(Method, Stream);
   } else {
     assert((isa<NamedDecl>(DC) || isa<BlockDecl>(DC)) &&
            "expected a NamedDecl or BlockDecl");
@@ -304,29 +304,70 @@ void MangleContext::mangleBlock(const DeclContext *DC, const BlockDecl *BD,
   mangleFunctionBlock(*this, Buffer, BD, Out);
 }
 
-void MangleContext::mangleObjCMethodNameWithoutSize(const ObjCMethodDecl *MD,
-                                                    raw_ostream &OS) {
-  const ObjCContainerDecl *CD =
-  dyn_cast<ObjCContainerDecl>(MD->getDeclContext());
-  assert (CD && "Missing container decl in GetNameForMethod");
+void MangleContext::mangleObjCMethodName(const ObjCMethodDecl *MD,
+                                         raw_ostream &OS,
+                                         bool includePrefixByte,
+                                         bool includeCategoryNamespace) {
+  if (getASTContext().getLangOpts().ObjCRuntime.isGNUFamily()) {
+    // This is the mangling we've always used on the GNU runtimes, but it
+    // has obvious collisions in the face of underscores within class
+    // names, category names, and selectors; maybe we should improve it.
+
+    OS << (MD->isClassMethod() ? "_c_" : "_i_")
+       << MD->getClassInterface()->getName() << '_';
+
+    if (includeCategoryNamespace) {
+      if (auto category = MD->getCategory())
+        OS << category->getName();
+    }
+    OS << '_';
+
+    auto selector = MD->getSelector();
+    for (unsigned slotIndex = 0,
+                  numArgs = selector.getNumArgs(),
+                  slotEnd = std::max(numArgs, 1U);
+           slotIndex != slotEnd; ++slotIndex) {
+      if (auto name = selector.getIdentifierInfoForSlot(slotIndex))
+        OS << name->getName();
+
+      // Replace all the positions that would've been ':' with '_'.
+      // That's after each slot except that a unary selector doesn't
+      // end in ':'.
+      if (numArgs)
+        OS << '_';
+    }
+
+    return;
+  }
+
+  // \01+[ContainerName(CategoryName) SelectorName]
+  if (includePrefixByte) {
+    OS << '\01';
+  }
   OS << (MD->isInstanceMethod() ? '-' : '+') << '[';
-  if (const ObjCCategoryImplDecl *CID = dyn_cast<ObjCCategoryImplDecl>(CD)) {
+  if (const auto *CID = MD->getCategory()) {
     OS << CID->getClassInterface()->getName();
-    OS << '(' << *CID << ')';
-  } else {
+    if (includeCategoryNamespace) {
+      OS << '(' << *CID << ')';
+    }
+  } else if (const auto *CD =
+                 dyn_cast<ObjCContainerDecl>(MD->getDeclContext())) {
     OS << CD->getName();
+  } else {
+    llvm_unreachable("Unexpected ObjC method decl context");
   }
   OS << ' ';
   MD->getSelector().print(OS);
   OS << ']';
 }
 
-void MangleContext::mangleObjCMethodName(const ObjCMethodDecl *MD,
-                                         raw_ostream &Out) {
+void MangleContext::mangleObjCMethodNameAsSourceName(const ObjCMethodDecl *MD,
+                                                     raw_ostream &Out) {
   SmallString<64> Name;
   llvm::raw_svector_ostream OS(Name);
 
-  mangleObjCMethodNameWithoutSize(MD, OS);
+  mangleObjCMethodName(MD, OS, /*includePrefixByte=*/false,
+                       /*includeCategoryNamespace=*/true);
   Out << OS.str().size() << OS.str();
 }
 
@@ -352,7 +393,8 @@ class ASTNameGenerator::Implementation {
       if (writeFuncOrVarName(VD, FrontendBufOS))
         return true;
     } else if (auto *MD = dyn_cast<ObjCMethodDecl>(D)) {
-      MC->mangleObjCMethodNameWithoutSize(MD, OS);
+      MC->mangleObjCMethodName(MD, OS, /*includePrefixByte=*/false,
+                               /*includeCategoryNamespace=*/true);
       return false;
     } else if (auto *ID = dyn_cast<ObjCInterfaceDecl>(D)) {
       writeObjCClassName(ID, FrontendBufOS);

diff --git a/clang/lib/AST/MicrosoftMangle.cpp b/clang/lib/AST/MicrosoftMangle.cpp
@@ -1321,7 +1321,7 @@ void MicrosoftCXXNameMangler::mangleSourceName(StringRef Name) {
 }
 
 void MicrosoftCXXNameMangler::mangleObjCMethodName(const ObjCMethodDecl *MD) {
-  Context.mangleObjCMethodName(MD, Out);
+  Context.mangleObjCMethodNameAsSourceName(MD, Out);
 }
 
 void MicrosoftCXXNameMangler::mangleTemplateInstantiationName(

diff --git a/clang/lib/CodeGen/CGObjCGNU.cpp b/clang/lib/CodeGen/CGObjCGNU.cpp
@@ -42,16 +42,6 @@ using namespace CodeGen;
 
 namespace {
 
-std::string SymbolNameForMethod( StringRef ClassName,
-     StringRef CategoryName, const Selector MethodName,
-    bool isClassMethod) {
-  std::string MethodNameColonStripped = MethodName.getAsString();
-  std::replace(MethodNameColonStripped.begin(), MethodNameColonStripped.end(),
-      ':', '_');
-  return (Twine(isClassMethod ? "_c_" : "_i_") + ClassName + "_" +
-    CategoryName + "_" + MethodNameColonStripped).str();
-}
-
 /// Class that lazily initialises the runtime function.  Avoids inserting the
 /// types and the function declaration into a module if they're not used, and
 /// avoids constructing the type more than once if it's used more than once.
@@ -2825,9 +2815,7 @@ GenerateMethodList(StringRef ClassName,
   ASTContext &Context = CGM.getContext();
   for (const auto *OMD : Methods) {
     llvm::Constant *FnPtr =
-      TheModule.getFunction(SymbolNameForMethod(ClassName, CategoryName,
-                                                OMD->getSelector(),
-                                                isClassMethodList));
+      TheModule.getFunction(getSymbolNameForMethod(OMD));
     assert(FnPtr && "Can't generate metadata for method that doesn't exist");
     auto Method = MethodArray.beginStruct(ObjCMethodTy);
     if (isV2ABI) {
@@ -3875,18 +3863,10 @@ llvm::Function *CGObjCGNU::ModuleInitFunction() {
 
 llvm::Function *CGObjCGNU::GenerateMethod(const ObjCMethodDecl *OMD,
                                           const ObjCContainerDecl *CD) {
-  const ObjCCategoryImplDecl *OCD =
-    dyn_cast<ObjCCategoryImplDecl>(OMD->getDeclContext());
-  StringRef CategoryName = OCD ? OCD->getName() : "";
-  StringRef ClassName = CD->getName();
-  Selector MethodName = OMD->getSelector();
-  bool isClassMethod = !OMD->isInstanceMethod();
-
   CodeGenTypes &Types = CGM.getTypes();
   llvm::FunctionType *MethodTy =
     Types.GetFunctionType(Types.arrangeObjCMethodDeclaration(OMD));
-  std::string FunctionName = SymbolNameForMethod(ClassName, CategoryName,
-      MethodName, isClassMethod);
+  std::string FunctionName = getSymbolNameForMethod(OMD);
 
   llvm::Function *Method
     = llvm::Function::Create(MethodTy,

diff --git a/clang/lib/CodeGen/CGObjCMac.cpp b/clang/lib/CodeGen/CGObjCMac.cpp
@@ -20,6 +20,7 @@
 #include "clang/AST/Attr.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclObjC.h"
+#include "clang/AST/Mangle.h"
 #include "clang/AST/RecordLayout.h"
 #include "clang/AST/StmtObjC.h"
 #include "clang/Basic/CodeGenOptions.h"
@@ -924,13 +925,6 @@ class CGObjCCommonMac : public CodeGen::CGObjCRuntime {
 
   llvm::StringMap<llvm::GlobalVariable *> NSConstantStringMap;
 
-  /// GetNameForMethod - Return a name for the given method.
-  /// \param[out] NameOut - The return value.
-  void GetNameForMethod(const ObjCMethodDecl *OMD,
-                        const ObjCContainerDecl *CD,
-                        SmallVectorImpl<char> &NameOut,
-                        bool ignoreCategoryNamespace = false);
-
   /// GetMethodVarName - Return a unique constant for the given
   /// selector's name. The return value has type char *.
   llvm::Constant *GetMethodVarName(Selector Sel);
@@ -1085,8 +1079,8 @@ class CGObjCCommonMac : public CodeGen::CGObjCRuntime {
   void EmitImageInfo();
 
 public:
-  CGObjCCommonMac(CodeGen::CodeGenModule &cgm) :
-    CGObjCRuntime(cgm), VMContext(cgm.getLLVMContext()) { }
+  CGObjCCommonMac(CodeGen::CodeGenModule &cgm)
+      : CGObjCRuntime(cgm), VMContext(cgm.getLLVMContext()) {}
 
   bool isNonFragileABI() const {
     return ObjCABI == 2;
@@ -4007,15 +4001,14 @@ llvm::Function *CGObjCCommonMac::GenerateMethod(const ObjCMethodDecl *OMD,
   if (OMD->isDirectMethod()) {
     Method = GenerateDirectMethod(OMD, CD);
   } else {
-    SmallString<256> Name;
-    GetNameForMethod(OMD, CD, Name);
+    auto Name = getSymbolNameForMethod(OMD);
 
     CodeGenTypes &Types = CGM.getTypes();
     llvm::FunctionType *MethodTy =
         Types.GetFunctionType(Types.arrangeObjCMethodDeclaration(OMD));
     Method =
         llvm::Function::Create(MethodTy, llvm::GlobalValue::InternalLinkage,
-                               Name.str(), &CGM.getModule());
+                               Name, &CGM.getModule());
   }
 
   MethodDefinitions.insert(std::make_pair(OMD, Method));
@@ -4060,11 +4053,10 @@ CGObjCCommonMac::GenerateDirectMethod(const ObjCMethodDecl *OMD,
     // Replace the cached function in the map.
     I->second = Fn;
   } else {
-    SmallString<256> Name;
-    GetNameForMethod(OMD, CD, Name, /*ignoreCategoryNamespace*/ true);
+    auto Name = getSymbolNameForMethod(OMD, /*include category*/ false);
 
     Fn = llvm::Function::Create(MethodTy, llvm::GlobalValue::ExternalLinkage,
-                                Name.str(), &CGM.getModule());
+                                Name, &CGM.getModule());
     DirectMethodDefinitions.insert(std::make_pair(COMD, Fn));
   }
 
@@ -5714,21 +5706,6 @@ CGObjCCommonMac::GetPropertyTypeString(const ObjCPropertyDecl *PD,
   return GetPropertyName(&CGM.getContext().Idents.get(TypeStr));
 }
 
-void CGObjCCommonMac::GetNameForMethod(const ObjCMethodDecl *D,
-                                       const ObjCContainerDecl *CD,
-                                       SmallVectorImpl<char> &Name,
-                                       bool ignoreCategoryNamespace) {
-  llvm::raw_svector_ostream OS(Name);
-  assert (CD && "Missing container decl in GetNameForMethod");
-  OS << '\01' << (D->isInstanceMethod() ? '-' : '+')
-     << '[' << CD->getName();
-  if (!ignoreCategoryNamespace)
-    if (const ObjCCategoryImplDecl *CID =
-        dyn_cast<ObjCCategoryImplDecl>(D->getDeclContext()))
-      OS << '(' << *CID << ')';
-  OS << ' ' << D->getSelector().getAsString() << ']';
-}
-
 void CGObjCMac::FinishModule() {
   EmitModuleInfo();
 

diff --git a/clang/lib/CodeGen/CGObjCRuntime.cpp b/clang/lib/CodeGen/CGObjCRuntime.cpp
@@ -390,3 +390,13 @@ clang::CodeGen::emitObjCProtocolObject(CodeGenModule &CGM,
                                        const ObjCProtocolDecl *protocol) {
   return CGM.getObjCRuntime().GetOrEmitProtocol(protocol);
 }
+
+std::string CGObjCRuntime::getSymbolNameForMethod(const ObjCMethodDecl *OMD,
+                                                  bool includeCategoryName) {
+  std::string buffer;
+  llvm::raw_string_ostream out(buffer);
+  CGM.getCXXABI().getMangleContext().mangleObjCMethodName(OMD, out,
+                                       /*includePrefixByte=*/true,
+                                       includeCategoryName);
+  return buffer;
+}
diff --git a/clang/lib/CodeGen/CGObjCRuntime.h b/clang/lib/CodeGen/CGObjCRuntime.h
@@ -115,6 +115,9 @@ class CGObjCRuntime {
 public:
   virtual ~CGObjCRuntime();
 
+  std::string getSymbolNameForMethod(const ObjCMethodDecl *method,
+                                     bool includeCategoryName = true);
+
   /// Generate the function required to register all Objective-C components in
   /// this compilation unit with the runtime library.
   virtual llvm::Function *ModuleInitFunction() = 0;

diff --git a/clang/test/AST/ast-dump-decl-json.m b/clang/test/AST/ast-dump-decl-json.m
@@ -836,7 +836,7 @@ void f() {
 // CHECK-NEXT:     }
 // CHECK-NEXT:    },
 // CHECK-NEXT:    "name": "bar",
-// CHECK-NEXT:    "mangledName": "-[TestObjCCategoryDecl bar]",
+// CHECK-NEXT:    "mangledName": "-[TestObjCClass(TestObjCCategoryDecl) bar]",
 // CHECK-NEXT:    "returnType": {
 // CHECK-NEXT:     "qualType": "void"
 // CHECK-NEXT:    },

diff --git a/llvm/tools/dsymutil/SymbolMap.cpp b/llvm/tools/dsymutil/SymbolMap.cpp
@@ -47,7 +47,7 @@ StringRef SymbolMapTranslator::operator()(StringRef Input) {
     return Translation;
 
   // Objective-C symbols for the MachO symbol table start with a \1. Please see
-  // `CGObjCCommonMac::GetNameForMethod` in clang.
+  // `MangleContext::mangleObjCMethodName` in clang.
   if (Translation[0] == 1)
     return StringRef(Translation).drop_front();