This patch implements Next's IRGen for -fconstant-string-class=class-name.

PR6056, //rdar: //8564463



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@116819 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CGObjCMac.cpp

@@ -1520,7 +1520,7 @@ llvm::Constant *CGObjCCommonMac::GenerateConstantString(
   const StringLiteral *SL) {
   return (CGM.getLangOptions().NoConstantCFStrings == 0 ? 
           CGM.GetAddrOfConstantCFString(SL) :
-          CGM.GetAddrOfConstantNSString(SL));
+          CGM.GetAddrOfConstantString(SL));
 }
 
 /// Generates a message send where the super is the receiver.  This is

lib/CodeGen/CodeGenModule.cpp

@@ -65,7 +65,7 @@ CodeGenModule::CodeGenModule(ASTContext &C, const CodeGenOptions &CGO,
     Types(C, M, TD, getTargetCodeGenInfo().getABIInfo(), ABI),
     TBAA(0),
     VTables(*this), Runtime(0),
-    CFConstantStringClassRef(0), NSConstantStringClassRef(0),
+    CFConstantStringClassRef(0), ConstantStringClassRef(0),
     VMContext(M.getContext()),
     NSConcreteGlobalBlockDecl(0), NSConcreteStackBlockDecl(0),
     NSConcreteGlobalBlock(0), NSConcreteStackBlock(0),
@@ -1635,7 +1635,7 @@ CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) {
 }
 
 llvm::Constant *
-CodeGenModule::GetAddrOfConstantNSString(const StringLiteral *Literal) {
+CodeGenModule::GetAddrOfConstantString(const StringLiteral *Literal) {
   unsigned StringLength = 0;
   bool isUTF16 = false;
   llvm::StringMapEntry<llvm::Constant*> &Entry =
@@ -1651,16 +1651,27 @@ CodeGenModule::GetAddrOfConstantNSString(const StringLiteral *Literal) {
   llvm::Constant *Zeros[] = { Zero, Zero };
   
   // If we don't already have it, get _NSConstantStringClassReference.
-  if (!NSConstantStringClassRef) {
+  if (!ConstantStringClassRef) {
+    std::string StringClass(getLangOptions().ObjCConstantStringClass);
     const llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
     Ty = llvm::ArrayType::get(Ty, 0);
-    llvm::Constant *GV = CreateRuntimeVariable(Ty, 
-                                        Features.ObjCNonFragileABI ?
-                                        "OBJC_CLASS_$_NSConstantString" :
-                                        "_NSConstantStringClassReference");
+    llvm::Constant *GV;
+    if (StringClass.empty())
+      GV = CreateRuntimeVariable(Ty, 
+                                 Features.ObjCNonFragileABI ?
+                                 "OBJC_CLASS_$_NSConstantString" :
+                                 "_NSConstantStringClassReference");
+    else {
+      std::string str;
+      if (Features.ObjCNonFragileABI)
+        str = "OBJC_CLASS_$_" + StringClass;
+      else
+        str = "_" + StringClass + "ClassReference";
+      GV = CreateRuntimeVariable(Ty, str);
+    }
     // Decay array -> ptr
-    NSConstantStringClassRef = 
-      llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2);
+    ConstantStringClassRef = 
+    llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2);
   }
   
   QualType NSTy = getContext().getNSConstantStringType();
@@ -1671,7 +1682,7 @@ CodeGenModule::GetAddrOfConstantNSString(const StringLiteral *Literal) {
   std::vector<llvm::Constant*> Fields(3);
   
   // Class pointer.
-  Fields[0] = NSConstantStringClassRef;
+  Fields[0] = ConstantStringClassRef;
   
   // String pointer.
   llvm::Constant *C = llvm::ConstantArray::get(VMContext, Entry.getKey().str());

lib/CodeGen/CodeGenModule.h

@@ -185,9 +185,9 @@ class CodeGenModule : public BlockModule {
   /// strings. This value has type int * but is actually an Obj-C class pointer.
   llvm::Constant *CFConstantStringClassRef;
 
-  /// NSConstantStringClassRef - Cached reference to the class for constant
+  /// ConstantStringClassRef - Cached reference to the class for constant
   /// strings. This value has type int * but is actually an Obj-C class pointer.
-  llvm::Constant *NSConstantStringClassRef;
+  llvm::Constant *ConstantStringClassRef;
 
   /// Lazily create the Objective-C runtime
   void createObjCRuntime();
@@ -321,9 +321,10 @@ public:
   /// for the given string.
   llvm::Constant *GetAddrOfConstantCFString(const StringLiteral *Literal);
   
-  /// GetAddrOfConstantNSString - Return a pointer to a constant NSString object
-  /// for the given string.
-  llvm::Constant *GetAddrOfConstantNSString(const StringLiteral *Literal);
+  /// GetAddrOfConstantString - Return a pointer to a constant NSString object
+  /// for the given string. Or a user defined String object as defined via
+  /// -fconstant-string-class=class_name option.
+  llvm::Constant *GetAddrOfConstantString(const StringLiteral *Literal);
 
   /// GetAddrOfConstantStringFromLiteral - Return a pointer to a constant array
   /// for the given string literal.

lib/Sema/SemaExprObjC.cpp

@@ -77,7 +77,14 @@ ExprResult Sema::ParseObjCStringLiteral(SourceLocation *AtLocs,
   if (!Ty.isNull()) {
     Ty = Context.getObjCObjectPointerType(Ty);
   } else if (getLangOptions().NoConstantCFStrings) {
-    IdentifierInfo *NSIdent = &Context.Idents.get("NSConstantString");
+    IdentifierInfo *NSIdent=0;
+    std::string StringClass(getLangOptions().ObjCConstantStringClass);
+    
+    if (StringClass.empty())
+      NSIdent = &Context.Idents.get("NSConstantString");
+    else
+      NSIdent = &Context.Idents.get(StringClass);
+    
     NamedDecl *IF = LookupSingleName(TUScope, NSIdent, AtLocs[0],
                                      LookupOrdinaryName);
     if (ObjCInterfaceDecl *StrIF = dyn_cast_or_null<ObjCInterfaceDecl>(IF)) {

test/CodeGenObjC/constant-string-class.m

@@ -0,0 +1,34 @@
+// RUN: %clang_cc1 -triple i386-apple-darwin9 -fno-constant-cfstrings -fconstant-string-class Foo -emit-llvm -o %t %s
+// RUN: FileCheck --check-prefix CHECK-FRAGILE < %t %s
+
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fobjc-nonfragile-abi -fno-constant-cfstrings -fconstant-string-class Foo -emit-llvm -o %t %s
+// RUN: FileCheck --check-prefix CHECK-NONFRAGILE < %t %s
+
+// rdar: // 8564463
+// PR6056
+
+@interface Object {
+  id isa;
+}
+@end
+
+@interface Foo : Object{
+  char *cString;
+  unsigned int len;
+}
+- (char *)customString;
+@end
+
+id _FooClassReference[20];
+
+@implementation Foo 
+- (char *)customString { return cString ; }
+@end
+
+int main () {
+  Foo *string = @"bla";
+  return 0;
+}
+
+// CHECK-FRAGILE: @_FooClassReference = common global
+// CHECK-NONFRAGILE: @"OBJC_CLASS_$_Object" = external global