diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index 1d9a9a6..bd14d1b 100644
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -856,9 +856,10 @@
 
   assert(FI.arg_size() == Args.size() &&
          "Mismatch between function signature & arguments.");
+  unsigned ArgNo = 1;
   CGFunctionInfo::const_arg_iterator info_it = FI.arg_begin();
-  for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end();
-       i != e; ++i, ++info_it) {
+  for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end(); 
+       i != e; ++i, ++info_it, ++ArgNo) {
     const VarDecl *Arg = i->first;
     QualType Ty = info_it->type;
     const ABIArgInfo &ArgI = info_it->info;
@@ -898,7 +899,7 @@
           V = EmitScalarConversion(V, Ty, Arg->getType());
         }
       }
-      EmitParmDecl(*Arg, V);
+      EmitParmDecl(*Arg, V, ArgNo);
       break;
     }
 
@@ -919,7 +920,7 @@
           // "void a(x) short x; {..."
           V = EmitScalarConversion(V, Ty, Arg->getType());
         }
-        EmitParmDecl(*Arg, V);
+        EmitParmDecl(*Arg, V, ArgNo);
         break;
       }
 
@@ -974,7 +975,7 @@
           V = EmitScalarConversion(V, Ty, Arg->getType());
         }
       }
-      EmitParmDecl(*Arg, V);
+      EmitParmDecl(*Arg, V, ArgNo);
       continue;  // Skip ++AI increment, already done.
     }
 
@@ -985,7 +986,7 @@
       llvm::Value *Temp = CreateMemTemp(Ty, Arg->getName() + ".addr");
       llvm::Function::arg_iterator End =
         ExpandTypeFromArgs(Ty, MakeAddrLValue(Temp, Ty), AI);
-      EmitParmDecl(*Arg, Temp);
+      EmitParmDecl(*Arg, Temp, ArgNo);
 
       // Name the arguments used in expansion and increment AI.
       unsigned Index = 0;
@@ -997,9 +998,10 @@
     case ABIArgInfo::Ignore:
       // Initialize the local variable appropriately.
       if (hasAggregateLLVMType(Ty))
-        EmitParmDecl(*Arg, CreateMemTemp(Ty));
+        EmitParmDecl(*Arg, CreateMemTemp(Ty), ArgNo);
       else
-        EmitParmDecl(*Arg, llvm::UndefValue::get(ConvertType(Arg->getType())));
+        EmitParmDecl(*Arg, llvm::UndefValue::get(ConvertType(Arg->getType())),
+                     ArgNo);
 
       // Skip increment, no matching LLVM parameter.
       continue;
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index 8038ce3..e6d2af3 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -1750,7 +1750,8 @@
 
 /// EmitDeclare - Emit local variable declaration debug info.
 void CGDebugInfo::EmitDeclare(const VarDecl *VD, unsigned Tag,
-                              llvm::Value *Storage, CGBuilderTy &Builder) {
+                              llvm::Value *Storage, 
+                              unsigned ArgNo, CGBuilderTy &Builder) {
   assert(!RegionStack.empty() && "Region stack mismatch, stack empty!");
 
   llvm::DIFile Unit = getOrCreateFile(VD->getLocation());
@@ -1810,7 +1811,7 @@
         DBuilder.createComplexVariable(Tag, 
                                        llvm::DIDescriptor(RegionStack.back()),
                                        VD->getName(), Unit, Line, Ty,
-                                       addr.data(), addr.size());
+                                       addr.data(), addr.size(), ArgNo);
       
       // Insert an llvm.dbg.declare into the current block.
       llvm::Instruction *Call =
@@ -1823,7 +1824,7 @@
     llvm::DIVariable D =
       DBuilder.createLocalVariable(Tag, llvm::DIDescriptor(Scope), 
                                    Name, Unit, Line, Ty, 
-                                   CGM.getLangOptions().Optimize, Flags);
+                                   CGM.getLangOptions().Optimize, Flags, ArgNo);
     
     // Insert an llvm.dbg.declare into the current block.
     llvm::Instruction *Call =
@@ -1853,7 +1854,8 @@
         llvm::DIVariable D =
           DBuilder.createLocalVariable(Tag, llvm::DIDescriptor(Scope),
                                        FieldName, Unit, Line, FieldTy, 
-                                       CGM.getLangOptions().Optimize, Flags);
+                                       CGM.getLangOptions().Optimize, Flags,
+                                       ArgNo);
           
         // Insert an llvm.dbg.declare into the current block.
         llvm::Instruction *Call =
@@ -1927,7 +1929,7 @@
 void CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *VD,
                                             llvm::Value *Storage,
                                             CGBuilderTy &Builder) {
-  EmitDeclare(VD, llvm::dwarf::DW_TAG_auto_variable, Storage, Builder);
+  EmitDeclare(VD, llvm::dwarf::DW_TAG_auto_variable, Storage, 0, Builder);
 }
 
 void CGDebugInfo::EmitDeclareOfBlockDeclRefVariable(
@@ -1940,8 +1942,9 @@
 /// EmitDeclareOfArgVariable - Emit call to llvm.dbg.declare for an argument
 /// variable declaration.
 void CGDebugInfo::EmitDeclareOfArgVariable(const VarDecl *VD, llvm::Value *AI,
+                                           unsigned ArgNo,
                                            CGBuilderTy &Builder) {
-  EmitDeclare(VD, llvm::dwarf::DW_TAG_arg_variable, AI, Builder);
+  EmitDeclare(VD, llvm::dwarf::DW_TAG_arg_variable, AI, ArgNo, Builder);
 }
 
 namespace {
@@ -2090,7 +2093,8 @@
     DBuilder.createLocalVariable(llvm::dwarf::DW_TAG_arg_variable,
                                  llvm::DIDescriptor(scope), 
                                  name, tunit, line, type, 
-                                 CGM.getLangOptions().Optimize, flags);
+                                 CGM.getLangOptions().Optimize, flags,
+                                 cast<llvm::Argument>(addr)->getArgNo() + 1);
     
   // Insert an llvm.dbg.value into the current block.
   llvm::Instruction *declare =
diff --git a/lib/CodeGen/CGDebugInfo.h b/lib/CodeGen/CGDebugInfo.h
index a390788..2e0f719 100644
--- a/lib/CodeGen/CGDebugInfo.h
+++ b/lib/CodeGen/CGDebugInfo.h
@@ -181,7 +181,7 @@
   /// EmitDeclareOfArgVariable - Emit call to llvm.dbg.declare for an argument
   /// variable declaration.
   void EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI,
-                                CGBuilderTy &Builder);
+                                unsigned ArgNo, CGBuilderTy &Builder);
 
   /// EmitDeclareOfBlockLiteralArgVariable - Emit call to
   /// llvm.dbg.declare for the block-literal argument to a block
@@ -204,7 +204,7 @@
 private:
   /// EmitDeclare - Emit call to llvm.dbg.declare for a variable declaration.
   void EmitDeclare(const VarDecl *decl, unsigned Tag, llvm::Value *AI,
-                   CGBuilderTy &Builder);
+                   unsigned ArgNo, CGBuilderTy &Builder);
 
   /// EmitDeclare - Emit call to llvm.dbg.declare for a variable
   /// declaration from an enclosing block.
diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index f4db01d..ecc0a4c 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -1000,7 +1000,8 @@
 
 /// Emit an alloca (or GlobalValue depending on target)
 /// for the specified parameter and set up LocalDeclMap.
-void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg) {
+void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg,
+                                   unsigned ArgNo) {
   // FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
   assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
          "Invalid argument to EmitParmDecl");
@@ -1046,6 +1047,6 @@
   // Emit debug info for param declaration.
   if (CGDebugInfo *DI = getDebugInfo()) {
     DI->setLocation(D.getLocation());
-    DI->EmitDeclareOfArgVariable(&D, DeclPtr, Builder);
+    DI->EmitDeclareOfArgVariable(&D, DeclPtr, ArgNo, Builder);
   }
 }
diff --git a/lib/CodeGen/CodeGenFunction.h b/lib/CodeGen/CodeGenFunction.h
index 0edd0f0..ef006d9 100644
--- a/lib/CodeGen/CodeGenFunction.h
+++ b/lib/CodeGen/CodeGenFunction.h
@@ -1609,7 +1609,7 @@
                          llvm::GlobalValue::LinkageTypes Linkage);
 
   /// EmitParmDecl - Emit a ParmVarDecl or an ImplicitParamDecl.
-  void EmitParmDecl(const VarDecl &D, llvm::Value *Arg);
+  void EmitParmDecl(const VarDecl &D, llvm::Value *Arg, unsigned ArgNo);
 
   /// protectFromPeepholes - Protect a value that we're intending to
   /// store to the side, but which will probably be used later, from