4 files changed, 37 insertions, 10 deletions

diff --git a/clang/CodeGen/CGExpr.cpp b/clang/CodeGen/CGExpr.cpp
index 63879ad66be..e6aaff15d55 100644
--- a/clang/CodeGen/CGExpr.cpp
+++ b/clang/CodeGen/CGExpr.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "CodeGenFunction.h"
+#include "CodeGenModule.h"
 #include "clang/AST/AST.h"
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
@@ -261,6 +262,8 @@ LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
     llvm::Value *V = LocalDeclMap[D];
     assert(V && "BlockVarDecl not entered in LocalDeclMap?");
     return LValue::getAddr(V);
+  } else if (isa<FunctionDecl>(D) || isa<FileVarDecl>(D)) {
+    return LValue::getAddr(CGM.GetAddrOfGlobalDecl(D));
   }
   assert(0 && "Unimp declref");
 }
diff --git a/clang/CodeGen/CodeGenFunction.cpp b/clang/CodeGen/CodeGenFunction.cpp
index d3abbc97e2b..3c4a68baeac 100644
--- a/clang/CodeGen/CodeGenFunction.cpp
+++ b/clang/CodeGen/CodeGenFunction.cpp
@@ -47,14 +47,11 @@ void CodeGenFunction::GenerateCode(const FunctionDecl *FD) {
   LLVMIntTy = ConvertType(getContext().IntTy, FD->getLocation());
   LLVMPointerWidth = Target.getPointerWidth(FD->getLocation());
   
-  const llvm::FunctionType *Ty = 
-    cast<llvm::FunctionType>(ConvertType(FD->getType(), FD->getLocation()));
-  
-  // FIXME: param attributes for sext/zext etc.
-  
+  CurFn = cast<llvm::Function>(CGM.GetAddrOfGlobalDecl(FD));
   CurFuncDecl = FD;
-  CurFn = new llvm::Function(Ty, llvm::Function::ExternalLinkage,
-                             FD->getName(), &CGM.getModule());
+  
+  // TODO: Set up linkage and many other things.
+  assert(CurFn->isDeclaration() && "Function already has body?");
   
   llvm::BasicBlock *EntryBB = new llvm::BasicBlock("entry", CurFn);
   
@@ -77,10 +74,10 @@ void CodeGenFunction::GenerateCode(const FunctionDecl *FD) {
   
   // Emit a return for code that falls off the end.
   // FIXME: if this is C++ main, this should return 0.
-  if (Ty->getReturnType() == llvm::Type::VoidTy)
+  if (CurFn->getReturnType() == llvm::Type::VoidTy)
     Builder.CreateRetVoid();
   else
-    Builder.CreateRet(llvm::UndefValue::get(Ty->getReturnType()));
+    Builder.CreateRet(llvm::UndefValue::get(CurFn->getReturnType()));
   
   // Verify that the function is well formed.
   assert(!verifyFunction(*CurFn));
diff --git a/clang/CodeGen/CodeGenModule.cpp b/clang/CodeGen/CodeGenModule.cpp
index 6ec9b796bd9..d4068c67532 100644
--- a/clang/CodeGen/CodeGenModule.cpp
+++ b/clang/CodeGen/CodeGenModule.cpp
@@ -15,6 +15,9 @@
 #include "CodeGenFunction.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/GlobalVariable.h"
 using namespace clang;
 using namespace CodeGen;
 
@@ -22,6 +25,27 @@ using namespace CodeGen;
 CodeGenModule::CodeGenModule(ASTContext &C, llvm::Module &M)
   : Context(C), TheModule(M), Types(C.Target) {}
 
+llvm::Constant *CodeGenModule::GetAddrOfGlobalDecl(const Decl *D) {
+  // See if it is already in the map.
+  llvm::Constant *&Entry = GlobalDeclMap[D];
+  if (Entry) return Entry;
+  
+  QualType ASTTy = cast<ValueDecl>(D)->getType();
+  const llvm::Type *Ty = getTypes().ConvertType(ASTTy, D->getLocation());
+  if (isa<FunctionDecl>(D)) {
+    const llvm::FunctionType *FTy = cast<llvm::FunctionType>(Ty);
+    // FIXME: param attributes for sext/zext etc.
+    return Entry = new llvm::Function(FTy, llvm::Function::ExternalLinkage,
+                                      D->getName(), &getModule());
+  }
+  
+  assert(isa<FileVarDecl>(D) && "Unknown global decl!");
+  
+  return Entry = new llvm::GlobalVariable(Ty, false, 
+                                          llvm::GlobalValue::ExternalLinkage,
+                                          0, D->getName(), &getModule());
+}
+
 void CodeGenModule::EmitFunction(FunctionDecl *FD) {
   // If this is not a prototype, emit the body.
   if (FD->getBody())
diff --git a/clang/CodeGen/CodeGenModule.h b/clang/CodeGen/CodeGenModule.h
index d72b84549c8..8e40483bd57 100644
--- a/clang/CodeGen/CodeGenModule.h
+++ b/clang/CodeGen/CodeGenModule.h
@@ -15,6 +15,7 @@
 #define CODEGEN_CODEGENMODULE_H
 
 #include "CodeGenTypes.h"
+#include "llvm/ADT/DenseMap.h"
 
 namespace llvm {
   class Module;
@@ -35,7 +36,7 @@ class CodeGenModule {
   llvm::Module &TheModule;
   CodeGenTypes Types;
 
-  //llvm::DenseMap<const Decl*, llvm::Constant*> GlobalDeclMap;
+  llvm::DenseMap<const Decl*, llvm::Constant*> GlobalDeclMap;
 public:
   CodeGenModule(ASTContext &C, llvm::Module &M);
   
@@ -43,6 +44,8 @@ public:
   llvm::Module &getModule() const { return TheModule; }
   CodeGenTypes &getTypes() { return Types; }
   
+  llvm::Constant *GetAddrOfGlobalDecl(const Decl *D);
+  
   void EmitFunction(FunctionDecl *FD);
   
   void PrintStats() {}