Add -fobjc-gc and -fobjc-gc-only options to the driver.

Add corresponding enum in LangOptions.

llvm-svn: 50387

clang/Driver/clang.cpp

@@ -358,6 +358,7 @@ LaxVectorConversions("flax-vector-conversions",
                      llvm::cl::desc("Allow implicit conversions between vectors"
                                     " with a different number of elements or "
                                     "different element types."));
+
 // FIXME: add:
 //   -ansi
 //   -trigraphs
@@ -425,6 +426,23 @@ static void InitializeLanguageStandard(LangOptions &Options, LangKind LK) {
   Options.LaxVectorConversions = LaxVectorConversions;
 }
 
+static llvm::cl::opt<bool>
+ObjCExclusiveGC("fobjc-gc-only",
+                llvm::cl::desc("Use GC exclusively for Objective-C related "
+                               "memory management."));
+
+static llvm::cl::opt<bool>
+ObjCEnableGC("fobjc-gc",
+             llvm::cl::desc("Enable Objective-C garbage collection."));             
+
+void InitializeGCMode(LangOptions &Options) {
+  if (ObjCExclusiveGC)
+    Options.setGCMode(LangOptions::GCOnly);
+  else if (ObjCEnableGC)
+    Options.setGCMode(LangOptions::HybridGC);
+}
+
+
 //===----------------------------------------------------------------------===//
 // Our DiagnosticClient implementation
 //===----------------------------------------------------------------------===//
@@ -1399,6 +1417,7 @@ int main(int argc, char **argv) {
       LangKind LK = GetLanguage(InFile);
       InitializeLangOptions(LangInfo, LK);
       InitializeLanguageStandard(LangInfo, LK);
+      InitializeGCMode(LangInfo);
       
       // Process the -I options and set them in the HeaderInfo.
       HeaderSearch HeaderInfo(FileMgr);

clang/include/clang/Basic/LangOptions.h

@@ -21,6 +21,7 @@ namespace clang {
 /// LangOptions - This class keeps track of the various options that can be
 /// enabled, which controls the dialect of C that is accepted.
 struct LangOptions {
+  
   unsigned Trigraphs         : 1;  // Trigraphs in source files.
   unsigned BCPLComment       : 1;  // BCPL-style '//' comments.
   unsigned DollarIdents      : 1;  // '$' allowed in identifiers.
@@ -34,23 +35,34 @@ struct LangOptions {
   unsigned NoExtensions      : 1;  // All extensions are disabled, strict mode.
   unsigned CXXOperatorNames  : 1;  // Treat C++ operator names as keywords.
     
-  unsigned ObjC1             : 1;  // Objective C 1 support enabled.
-  unsigned ObjC2             : 1;  // Objective C 2 support enabled.
+  unsigned ObjC1             : 1;  // Objective-C 1 support enabled.
+  unsigned ObjC2             : 1;  // Objective-C 2 support enabled.
     
   unsigned PascalStrings     : 1;  // Allow Pascal strings
   unsigned Boolean           : 1;  // Allow bool/true/false
   unsigned WritableStrings   : 1;  // Allow writable strings
   unsigned LaxVectorConversions : 1;
   
+private:
+  unsigned GC : 2; // Objective-C Garbage Collection modes.  We declare
+                   // this enum as unsigned because MSVC insists on making enums
+                   // signed.  Set/Query this value using accessors.  
+public:  
+
+  enum GCMode { NonGC, GCOnly, HybridGC };
+  
   LangOptions() {
     Trigraphs = BCPLComment = DollarIdents = ImplicitInt = Digraphs = 0;
     HexFloats = 0;
-    ObjC1 = ObjC2 = 0;
+    GC = ObjC1 = ObjC2 = 0;
     C99 = Microsoft = CPlusPlus = CPlusPlus0x = NoExtensions = 0;
     CXXOperatorNames = PascalStrings = Boolean = WritableStrings = 0;
     LaxVectorConversions = 0;
   }
   
+  GCMode getGCMode() const { return (GCMode) GC; }
+  void setGCMode(GCMode m) { GC = (unsigned) m; }
+  
   /// Emit - Emit this LangOptions object to bitcode.
   void Emit(llvm::Serializer& S) const;
   

clang/lib/Basic/LangOptions.cpp

@@ -31,6 +31,7 @@ void LangOptions::Emit(llvm::Serializer& S) const {
   S.EmitBool((bool) CXXOperatorNames);             
   S.EmitBool((bool) ObjC1);
   S.EmitBool((bool) ObjC2);
+  S.EmitBool((unsigned) GC);
   S.EmitBool((bool) PascalStrings);
   S.EmitBool((bool) Boolean);
   S.EmitBool((bool) WritableStrings);
@@ -51,6 +52,7 @@ void LangOptions::Read(llvm::Deserializer& D) {
   CXXOperatorNames = D.ReadBool() ? 1 : 0;
   ObjC1 = D.ReadBool() ? 1 : 0;
   ObjC2 = D.ReadBool() ? 1 : 0;
+  GC = D.ReadInt();
   PascalStrings = D.ReadBool() ? 1 : 0;
   Boolean = D.ReadBool() ? 1 : 0;
   WritableStrings = D.ReadBool() ? 1 : 0;