Revert "Numerous changes to selector handling:", this breaks a whole bunch of

working code, for no apparent reason.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@95244 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/AST/ExprObjC.h

@@ -96,22 +96,18 @@ public:
 /// ObjCSelectorExpr used for @selector in Objective-C.
 class ObjCSelectorExpr : public Expr {
   Selector SelName;
-  ObjCMethodDecl *Method;
   SourceLocation AtLoc, RParenLoc;
 public:
   ObjCSelectorExpr(QualType T, Selector selInfo,
                    SourceLocation at, SourceLocation rp)
-  : Expr(ObjCSelectorExprClass, T, false, false), SelName(selInfo), Method(0),
-    AtLoc(at), RParenLoc(rp){}
+  : Expr(ObjCSelectorExprClass, T, false, false), SelName(selInfo), AtLoc(at),
+    RParenLoc(rp){}
   explicit ObjCSelectorExpr(EmptyShell Empty)
    : Expr(ObjCSelectorExprClass, Empty) {}
 
   Selector getSelector() const { return SelName; }
   void setSelector(Selector S) { SelName = S; }
 
-  ObjCMethodDecl *getMethodDecl() const { return Method; }
-  void setMethodDecl(ObjCMethodDecl *M) { Method = M; }
-
   SourceLocation getAtLoc() const { return AtLoc; }
   SourceLocation getRParenLoc() const { return RParenLoc; }
   void setAtLoc(SourceLocation L) { AtLoc = L; }

lib/AST/Expr.cpp

@@ -1454,7 +1454,6 @@ bool Expr::isConstantInitializer(ASTContext &Ctx) const {
   case StringLiteralClass:
   case ObjCStringLiteralClass:
   case ObjCEncodeExprClass:
-  case ObjCSelectorExprClass:
     return true;
   case CompoundLiteralExprClass: {
     // This handles gcc's extension that allows global initializers like

lib/CodeGen/CGExprConstant.cpp

@@ -701,14 +701,6 @@ public:
                                     CGM.GetStringForStringLiteral(E), false);
   }
 
-  llvm::Constant *VisitObjCSelectorExpr(const ObjCSelectorExpr *E) {
-    ObjCMethodDecl *OMD = E->getMethodDecl();
-    if (OMD)
-      return CGM.getObjCRuntime().GetConstantTypedSelector(OMD);
-    else 
-      return CGM.getObjCRuntime().GetConstantSelector(E->getSelector());
-  }
-
   llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E) {
     // This must be an @encode initializing an array in a static initializer.
     // Don't emit it as the address of the string, emit the string data itself

lib/CodeGen/CGObjC.cpp

@@ -38,11 +38,7 @@ llvm::Value *CodeGenFunction::EmitObjCSelectorExpr(const ObjCSelectorExpr *E) {
   // Note that this implementation allows for non-constant strings to be passed
   // as arguments to @selector().  Currently, the only thing preventing this
   // behaviour is the type checking in the front end.
-  ObjCMethodDecl *OMD = E->getMethodDecl();
-  if (OMD)
-    return CGM.getObjCRuntime().GetSelector(Builder, OMD);
-  else 
-    return CGM.getObjCRuntime().GetSelector(Builder, E->getSelector());
+  return CGM.getObjCRuntime().GetSelector(Builder, E->getSelector());
 }
 
 llvm::Value *CodeGenFunction::EmitObjCProtocolExpr(const ObjCProtocolExpr *E) {

lib/CodeGen/CGObjCGNU.cpp

@@ -156,17 +156,9 @@ public:
                            const ObjCMethodDecl *Method);
   virtual llvm::Value *GetClass(CGBuilderTy &Builder,
                                 const ObjCInterfaceDecl *OID);
-  virtual llvm::Constant *GetConstantSelector(Selector Sel);
-  virtual llvm::Constant *GetConstantTypedSelector(
-     const ObjCMethodDecl *Method);
-  llvm::Value *GetSelector(CGBuilderTy &Builder,
-                           Selector Sel) {
-    return cast<llvm::Constant>((GetConstantSelector(Sel)));
-  }
-  llvm::Value *GetSelector(CGBuilderTy &Builder,
-                           const ObjCMethodDecl *Method) {
-    return cast<llvm::Constant>(GetConstantTypedSelector(Method));
-  }
+  virtual llvm::Value *GetSelector(CGBuilderTy &Builder, Selector Sel);
+  virtual llvm::Value *GetSelector(CGBuilderTy &Builder, const ObjCMethodDecl
+      *Method);
 
   virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,
                                          const ObjCContainerDecl *CD);
@@ -347,18 +339,18 @@ llvm::Value *CGObjCGNU::GetClass(CGBuilderTy &Builder,
   return Builder.CreateCall(ClassLookupFn, ClassName);
 }
 
-llvm::Constant *CGObjCGNU::GetConstantSelector(Selector Sel) {
+llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, Selector Sel) {
   llvm::GlobalAlias *&US = UntypedSelectors[Sel.getAsString()];
   if (US == 0)
-    US = new llvm::GlobalAlias(SelectorTy,
+    US = new llvm::GlobalAlias(llvm::PointerType::getUnqual(SelectorTy),
                                llvm::GlobalValue::PrivateLinkage,
                                ".objc_untyped_selector_alias"+Sel.getAsString(),
                                NULL, &TheModule);
 
-  return US;
+  return Builder.CreateLoad(US);
 }
 
-llvm::Constant *CGObjCGNU::GetConstantTypedSelector(const ObjCMethodDecl
+llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, const ObjCMethodDecl
     *Method) {
 
   std::string SelName = Method->getSelector().getAsString();
@@ -370,17 +362,17 @@ llvm::Constant *CGObjCGNU::GetConstantTypedSelector(const ObjCMethodDecl
 
   // If it's already cached, return it.
   if (TypedSelectors[Selector]) {
-    return TypedSelectors[Selector];
+    return Builder.CreateLoad(TypedSelectors[Selector]);
   }
 
   // If it isn't, cache it.
   llvm::GlobalAlias *Sel = new llvm::GlobalAlias(
-          SelectorTy,
+          llvm::PointerType::getUnqual(SelectorTy),
           llvm::GlobalValue::PrivateLinkage, ".objc_selector_alias" + SelName,
           NULL, &TheModule);
   TypedSelectors[Selector] = Sel;
 
-  return Sel;
+  return Builder.CreateLoad(Sel);
 }
 
 llvm::Constant *CGObjCGNU::MakeConstantString(const std::string &Str,
@@ -1537,43 +1529,40 @@ llvm::Function *CGObjCGNU::ModuleInitFunction() {
 
   // Now that all of the static selectors exist, create pointers to them.
   int index = 0;
-  llvm::SmallVector<std::pair<llvm::GlobalAlias*,llvm::Value*>, 16> selectors;
   for (std::map<TypedSelector, llvm::GlobalAlias*>::iterator
      iter=TypedSelectors.begin(), iterEnd =TypedSelectors.end();
      iter != iterEnd; ++iter) {
     llvm::Constant *Idxs[] = {Zeros[0],
       llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), index++), Zeros[0]};
-    llvm::Constant *SelPtr = 
-        llvm::ConstantExpr::getGetElementPtr(SelectorList, Idxs, 2);
+    llvm::Constant *SelPtr = new llvm::GlobalVariable(TheModule, SelStructPtrTy,
+        true, llvm::GlobalValue::InternalLinkage,
+        llvm::ConstantExpr::getGetElementPtr(SelectorList, Idxs, 2),
+        ".objc_sel_ptr");
     // If selectors are defined as an opaque type, cast the pointer to this
     // type.
     if (isSelOpaque) {
-      SelPtr = llvm::ConstantExpr::getBitCast(SelPtr,SelectorTy);
+      SelPtr = llvm::ConstantExpr::getBitCast(SelPtr,
+        llvm::PointerType::getUnqual(SelectorTy));
     }
-    selectors.push_back(
-        std::pair<llvm::GlobalAlias*,llvm::Value*>((*iter).second, SelPtr));
+    (*iter).second->setAliasee(SelPtr);
   }
   for (llvm::StringMap<llvm::GlobalAlias*>::iterator
       iter=UntypedSelectors.begin(), iterEnd = UntypedSelectors.end();
       iter != iterEnd; iter++) {
     llvm::Constant *Idxs[] = {Zeros[0],
       llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), index++), Zeros[0]};
-    llvm::Constant *SelPtr = 
-       llvm::ConstantExpr::getGetElementPtr(SelectorList, Idxs, 2);
+    llvm::Constant *SelPtr = new llvm::GlobalVariable
+      (TheModule, SelStructPtrTy,
+       true, llvm::GlobalValue::InternalLinkage,
+       llvm::ConstantExpr::getGetElementPtr(SelectorList, Idxs, 2),
+       ".objc_sel_ptr");
     // If selectors are defined as an opaque type, cast the pointer to this
     // type.
     if (isSelOpaque) {
-      SelPtr = llvm::ConstantExpr::getBitCast(SelPtr, SelectorTy);
+      SelPtr = llvm::ConstantExpr::getBitCast(SelPtr,
+        llvm::PointerType::getUnqual(SelectorTy));
     }
-    selectors.push_back(
-        std::pair<llvm::GlobalAlias*,llvm::Value*>((*iter).second, SelPtr));
-  }
-  for (llvm::SmallVectorImpl<std::pair<
-            llvm::GlobalAlias*,llvm::Value*> >::iterator
-     iter=selectors.begin(), iterEnd =selectors.end();
-     iter != iterEnd; ++iter) {
-    iter->first->replaceAllUsesWith(iter->second);
-    iter->first->eraseFromParent();
+    (*iter).second->setAliasee(SelPtr);
   }
   // Number of classes defined.
   Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext),

lib/CodeGen/CGObjCMac.cpp

@@ -953,14 +953,6 @@ public:
   CGObjCCommonMac(CodeGen::CodeGenModule &cgm) :
     CGM(cgm), VMContext(cgm.getLLVMContext()) { }
 
-  virtual llvm::Constant *GetConstantSelector(Selector Sel) {
-    assert(0 && "Constant Selectors are not yet supported on the Mac runtimes");
-    return 0;
-  }
-  virtual llvm::Constant *GetConstantTypedSelector(
-     const ObjCMethodDecl *Method) {
-    return GetConstantSelector(Method->getSelector());
-  }
   virtual llvm::Constant *GenerateConstantString(const StringLiteral *SL);
 
   virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,

lib/CodeGen/CGObjCRuntime.h

@@ -95,12 +95,6 @@ public:
   /// this compilation unit with the runtime library.
   virtual llvm::Function *ModuleInitFunction() = 0;
 
-  virtual llvm::Constant *GetConstantSelector(Selector Sel) = 0;
-
-  /// Get a typed selector.
-  virtual llvm::Constant *GetConstantTypedSelector(
-     const ObjCMethodDecl *Method) = 0;
-
   /// Get a selector for the specified name and type values. The
   /// return value should have the LLVM type for pointer-to
   /// ASTContext::getObjCSelType().

lib/Sema/SemaExprObjC.cpp

@@ -140,20 +140,7 @@ Sema::ExprResult Sema::ParseObjCSelectorExpression(Selector Sel,
     Diag(SelLoc, diag::warn_undeclared_selector) << Sel;
 
   QualType Ty = Context.getObjCSelType();
-  ObjCSelectorExpr *E = 
-      new (Context) ObjCSelectorExpr(Ty, Sel, AtLoc, RParenLoc);
-  // Make sure that we have seen this selector.  There are lots of checks we
-  // should be doing on this selector.  For example, when this is passed as the
-  // second argument to objc_msgSend() on the Mac runtime, or as the selector
-  // argument to the -performSelector:.  We can do these checks at run time
-  // with the GNU runtimes, but the Apple runtimes let you sneak stack
-  // corruption in easily by passing the wrong selector to these functions if
-  // there is no static checking.
-  //
-  // Only log a warning on the GNU runtime.
-  E->setMethodDecl(LookupInstanceMethodInGlobalPool(Sel, 
-      SourceRange(LParenLoc,  LParenLoc), !LangOpts.NeXTRuntime));
-  return E;
+  return new (Context) ObjCSelectorExpr(Ty, Sel, AtLoc, RParenLoc);
 }
 
 Sema::ExprResult Sema::ParseObjCProtocolExpression(IdentifierInfo *ProtocolId,