Add LangOptions::NeXTRuntime.

 - Wired to -fnext-runtime and -fgnu-runtime options.
 - Defaults to GNU, no autoselection for NeXT.

Emit NeXT OBJC_IMAGE_INFO marker.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@54651 91177308-0d34-0410-b5e6-96231b3b80d8

7 files changed, 117 insertions, 10 deletions

diff --git a/Driver/clang.cpp b/Driver/clang.cpp
index c55aa17eb2..089faf1255 100644
--- a/Driver/clang.cpp
+++ b/Driver/clang.cpp
@@ -373,6 +373,14 @@ static llvm::cl::opt<bool>
 Exceptions("fexceptions",
            llvm::cl::desc("Enable support for exception handling."));
 
+static llvm::cl::opt<bool>
+GNURuntime("fgnu-runtime",
+            llvm::cl::desc("Generate output compatible with the standard GNU Objective-C runtime."));
+
+static llvm::cl::opt<bool>
+NeXTRuntime("fnext-runtime",
+            llvm::cl::desc("Generate output compatible with the NeXT runtime."));
+
 // FIXME: add:
 //   -ansi
 //   -trigraphs
@@ -439,6 +447,15 @@ static void InitializeLanguageStandard(LangOptions &Options, LangKind LK) {
   Options.WritableStrings = WritableStrings;
   Options.LaxVectorConversions = LaxVectorConversions;
   Options.Exceptions = Exceptions;
+
+  if (NeXTRuntime) {
+    Options.NeXTRuntime = 1;
+  } else if (GNURuntime) {
+    Options.NeXTRuntime = 0;
+  } else {
+    // FIXME: Should autoselect based on platform.
+    Options.NeXTRuntime = 0;
+  }
 }
 
 static llvm::cl::opt<bool>
diff --git a/include/clang/Basic/LangOptions.h b/include/clang/Basic/LangOptions.h
index 7756a2ab5b..c07fdfe47c 100644
--- a/include/clang/Basic/LangOptions.h
+++ b/include/clang/Basic/LangOptions.h
@@ -43,7 +43,9 @@ struct LangOptions {
   unsigned WritableStrings   : 1;  // Allow writable strings
   unsigned LaxVectorConversions : 1;
   unsigned Exceptions        : 1;  // Support exception handling.
-  
+
+  unsigned NeXTRuntime       : 1; // Use NeXT runtime.
+
 private:
   unsigned GC : 2; // Objective-C Garbage Collection modes.  We declare
                    // this enum as unsigned because MSVC insists on making enums
@@ -58,7 +60,7 @@ public:
     GC = ObjC1 = ObjC2 = 0;
     C99 = Microsoft = CPlusPlus = CPlusPlus0x = NoExtensions = 0;
     CXXOperatorNames = PascalStrings = Boolean = WritableStrings = 0;
-    LaxVectorConversions = Exceptions = 0;
+    LaxVectorConversions = Exceptions = NeXTRuntime = 0;    
   }
   
   GCMode getGCMode() const { return (GCMode) GC; }
diff --git a/lib/Basic/Targets.cpp b/lib/Basic/Targets.cpp
index 214dfb16de..bc35d7fe8e 100644
--- a/lib/Basic/Targets.cpp
+++ b/lib/Basic/Targets.cpp
@@ -53,7 +53,7 @@ public:
     Define(Defs, "linux");
 #endif
     
-    if (1) {// -fobjc-gc controls this.
+    if (1) { // FIXME: -fobjc-gc controls this.
       Define(Defs, "__weak", "");
       Define(Defs, "__strong", "");
     } else {
@@ -67,6 +67,9 @@ public:
     
     if (0)  // darwin_pascal_strings
       Define(Defs, "__PASCAL_STRINGS__");
+
+    if (0) // FIXME: -fnext-runtime controls this
+      Define(Defs, "__NEXT_RUNTIME__");
   }
 
 };
diff --git a/lib/CodeGen/CGObjCMac.cpp b/lib/CodeGen/CGObjCMac.cpp
index faf6fa94fc..205a8f55e9 100644
--- a/lib/CodeGen/CGObjCMac.cpp
+++ b/lib/CodeGen/CGObjCMac.cpp
@@ -12,7 +12,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "CGObjCRuntime.h"
+
+#include "CodeGenModule.h"
 #include "clang/AST/Decl.h"
+#include "clang/Basic/LangOptions.h"
+
 #include "llvm/Support/IRBuilder.h"
 
 using namespace clang;
@@ -22,6 +26,18 @@ class CGObjCMac : public CodeGen::CGObjCRuntime {
 private:
   CodeGen::CodeGenModule &CGM;
 
+  /// UsedGlobals - list of globals to pack into the llvm.used metadata
+  /// to prevent them from being clobbered.
+  std::vector<llvm::GlobalValue*> UsedGlobals;
+
+  /// EmitImageInfo - Emit the image info marker used to encode some module
+  /// level information.
+  void EmitImageInfo();
+
+  /// FinishModule - Write out global data structures at the end of
+  /// processing a translation unit.
+  void FinishModule();
+
 public:
   CGObjCMac(CodeGen::CodeGenModule &cgm);
   virtual llvm::Constant *GenerateConstantString(const char *String, 
@@ -94,6 +110,7 @@ public:
 } // end anonymous namespace
  
 CGObjCMac::CGObjCMac(CodeGen::CodeGenModule &cgm) : CGM(cgm) {
+  EmitImageInfo();
 }
 
 // This has to perform the lookup every time, since posing and related
@@ -186,6 +203,9 @@ void CGObjCMac::GenerateClass(
 }
 
 llvm::Function *CGObjCMac::ModuleInitFunction() { 
+  // Abuse this interface function as a place to finalize.
+  FinishModule();
+
   return NULL;
 }
 
@@ -203,6 +223,74 @@ llvm::Function *CGObjCMac::MethodPreamble(
   return 0;
 }
 
+/* *** Private Interface *** */
+
+/// EmitImageInfo - Emit the image info marker used to encode some module
+/// level information.
+///
+/// See: <rdr://4810609&4810587&4810587>
+/// struct IMAGE_INFO {
+///   unsigned version;
+///   unsigned flags;
+/// };
+enum ImageInfoFlags {
+  eImageInfo_FixAndContinue   = (1 << 0), // FIXME: Not sure what this implies
+  eImageInfo_GarbageCollected = (1 << 1), 
+  eImageInfo_GCOnly           = (1 << 2)  
+};
+
+void CGObjCMac::EmitImageInfo() {
+  unsigned version = 0; // Version is unused?
+  unsigned flags = 0;
+
+  // FIXME: Fix and continue?
+  if (CGM.getLangOptions().getGCMode() != LangOptions::NonGC)
+    flags |= eImageInfo_GarbageCollected;
+  if (CGM.getLangOptions().getGCMode() == LangOptions::GCOnly)
+    flags |= eImageInfo_GCOnly;
+
+  fprintf(stderr, "flags: %d (%d)\n", flags, CGM.getLangOptions().getGCMode());
+
+  // Emitted as int[2];
+  llvm::Constant *values[2] = {
+    llvm::ConstantInt::get(llvm::Type::Int32Ty, version),
+    llvm::ConstantInt::get(llvm::Type::Int32Ty, flags)
+  };
+  llvm::ArrayType *AT = llvm::ArrayType::get(llvm::Type::Int32Ty, 2);  
+  llvm::GlobalValue *GV = 
+    new llvm::GlobalVariable(AT, true,
+                             llvm::GlobalValue::InternalLinkage,
+                             llvm::ConstantArray::get(AT, values, 2),
+                             "\01L_OBJC_IMAGE_INFO", 
+                             &CGM.getModule());
+
+  GV->setSection("__OBJC, __image_info,regular");
+
+  UsedGlobals.push_back(GV);
+}
+
+void CGObjCMac::FinishModule() {
+  std::vector<llvm::Constant*> Used;
+  
+  llvm::Type *I8Ptr = llvm::PointerType::getUnqual(llvm::Type::Int8Ty);
+  for (std::vector<llvm::GlobalValue*>::iterator i = UsedGlobals.begin(), 
+         e = UsedGlobals.end(); i != e; ++i) {
+    Used.push_back(llvm::ConstantExpr::getBitCast(*i, I8Ptr));
+  }
+  
+  llvm::ArrayType *AT = llvm::ArrayType::get(I8Ptr, Used.size());
+  llvm::GlobalValue *GV = 
+    new llvm::GlobalVariable(AT, false,
+                             llvm::GlobalValue::AppendingLinkage,
+                             llvm::ConstantArray::get(AT, Used),
+                             "llvm.used", 
+                             &CGM.getModule());
+
+  GV->setSection("llvm.metadata");
+}
+
+/* *** */
+
 CodeGen::CGObjCRuntime *CodeGen::CreateMacObjCRuntime(CodeGen::CodeGenModule &CGM){
   return new CGObjCMac(CGM);
 }
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 347f4d24f9..fb873c2a67 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -30,15 +30,13 @@ using namespace CodeGen;
 
 CodeGenModule::CodeGenModule(ASTContext &C, const LangOptions &LO,
                              llvm::Module &M, const llvm::TargetData &TD,
-                             Diagnostic &diags, bool GenerateDebugInfo,
-                             bool UseMacObjCRuntime)
+                             Diagnostic &diags, bool GenerateDebugInfo)
   : Context(C), Features(LO), TheModule(M), TheTargetData(TD), Diags(diags),
     Types(C, M, TD), Runtime(0), MemCpyFn(0), MemMoveFn(0), MemSetFn(0),
     CFConstantStringClassRef(0) {
 
   if (Features.ObjC1) {
-    // TODO: Make this selectable at runtime
-    if (UseMacObjCRuntime) {
+    if (Features.NeXTRuntime) {
       Runtime = CreateMacObjCRuntime(*this);
     } else {
       Runtime = CreateGNUObjCRuntime(*this);
diff --git a/lib/CodeGen/CodeGenModule.h b/lib/CodeGen/CodeGenModule.h
index 0b313c4205..3f30cd3283 100644
--- a/lib/CodeGen/CodeGenModule.h
+++ b/lib/CodeGen/CodeGenModule.h
@@ -105,7 +105,7 @@ class CodeGenModule {
 public:
   CodeGenModule(ASTContext &C, const LangOptions &Features, llvm::Module &M, 
                 const llvm::TargetData &TD, Diagnostic &Diags,
-                bool GenerateDebugInfo, bool UseMacObjCRuntime);
+                bool GenerateDebugInfo);
 
   ~CodeGenModule();
   
diff --git a/lib/CodeGen/ModuleBuilder.cpp b/lib/CodeGen/ModuleBuilder.cpp
index 7c43943eac..affef35f28 100644
--- a/lib/CodeGen/ModuleBuilder.cpp
+++ b/lib/CodeGen/ModuleBuilder.cpp
@@ -59,8 +59,7 @@ namespace {
       M->setDataLayout(Ctx->Target.getTargetDescription());
       TD.reset(new llvm::TargetData(Ctx->Target.getTargetDescription()));
       Builder.reset(new CodeGen::CodeGenModule(Context, Features, *M, *TD,
-                                               Diags, GenerateDebugInfo,
-                                               false));
+                                               Diags, GenerateDebugInfo));
     }
     
     virtual void HandleTopLevelDecl(Decl *D) {