This patch makes Clang-independent base classes for all the expression types that lldb currently vends.

Before we had:

ClangFunction
ClangUtilityFunction
ClangUserExpression

and code all over in lldb that explicitly made Clang-based expressions. This patch adds an Expression 
base class, and three pure virtual implementations for the Expression kinds:

FunctionCaller
UtilityFunction
UserExpression

You can request one of these expression types from the Target using the Get<ExpressionType>ForLanguage. 
The Target will then consult all the registered TypeSystem plugins, and if the type system that matches 
the language can make an expression of that kind, it will do so and return it.

Because all of the real expression types need to communicate with their ExpressionParser in a uniform way, 
I also added a ExpressionTypeSystemHelper class that expressions generically can vend, and a ClangExpressionHelper 
that encapsulates the operations that the ClangExpressionParser needs to perform on the ClangExpression types. 
Then each of the Clang* expression kinds constructs the appropriate helper to do what it needs.

The patch also fixes a wart in the UtilityFunction that to use it you had to create a parallel FunctionCaller 
to actually call the function made by the UtilityFunction. Now the UtilityFunction can be asked to vend a 
FunctionCaller that will run its function. This cleaned up a lot of boiler plate code using UtilityFunctions.

Note, in this patch all the expression types explicitly depend on the LLVM JIT and IR, and all the common 
JIT running code is in the FunctionCaller etc base classes. At some point we could also abstract that dependency 
but I don't see us adding another back end in the near term, so I'll leave that exercise till it is actually necessary.

llvm-svn: 247720

11 files changed, 199 insertions, 218 deletions

diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCClassDescriptorV2.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCClassDescriptorV2.cpp
index 7a519532036..925e49883b5 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCClassDescriptorV2.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCClassDescriptorV2.cpp
@@ -8,7 +8,9 @@
 //===----------------------------------------------------------------------===//
 
 #include "AppleObjCClassDescriptorV2.h"
+
 #include "lldb/Core/Log.h"
+#include "lldb/Expression/FunctionCaller.h"
 
 using namespace lldb;
 using namespace lldb_private;
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
index 81ae61841ae..b4b725ea3cc 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
@@ -1,4 +1,4 @@
-//===-- AppleObjCRuntime.cpp --------------------------------------*- C++ -*-===//
+//===-- AppleObjCRuntime.cpp -------------------------------------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -22,7 +22,8 @@
 #include "lldb/Core/Scalar.h"
 #include "lldb/Core/Section.h"
 #include "lldb/Core/StreamString.h"
-#include "lldb/Expression/ClangFunction.h"
+#include "lldb/Core/ValueObject.h"
+#include "lldb/Expression/FunctionCaller.h"
 #include "lldb/Symbol/ClangASTContext.h"
 #include "lldb/Symbol/ObjectFile.h"
 #include "lldb/Target/ExecutionContext.h"
@@ -39,6 +40,10 @@ using namespace lldb_private;
 
 #define PO_FUNCTION_TIMEOUT_USEC 15*1000*1000
 
+AppleObjCRuntime::~AppleObjCRuntime()
+{
+}
+
 AppleObjCRuntime::AppleObjCRuntime(Process *process) :
     ObjCLanguageRuntime (process),
     m_read_objc_library (false),
@@ -135,16 +140,36 @@ AppleObjCRuntime::GetObjectDescription (Stream &strm, Value &value, ExecutionCon
     }
     
     // Now we're ready to call the function:
-    ClangFunction func (*exe_ctx.GetBestExecutionContextScope(),
-                        return_clang_type, 
-                        *function_address, 
-                        arg_value_list,
-                        "objc-object-description");
-
-    StreamString error_stream;
     
+    StreamString error_stream;
     lldb::addr_t wrapper_struct_addr = LLDB_INVALID_ADDRESS;
-    func.InsertFunction(exe_ctx, wrapper_struct_addr, error_stream);
+
+    if (!m_print_object_caller_up)
+    {
+        Error error;
+         m_print_object_caller_up.reset(exe_scope->CalculateTarget()->GetFunctionCallerForLanguage (eLanguageTypeObjC,
+                                                                                                    return_clang_type,
+                                                                                                    *function_address,
+                                                                                                    arg_value_list,
+                                                                                                    "objc-object-description",
+                                                                                                    error));
+        if (error.Fail())
+        {
+            m_print_object_caller_up.reset();
+            strm.Printf("Could not get function runner to call print for debugger function: %s.", error.AsCString());
+            return false;
+        }
+        m_print_object_caller_up->InsertFunction(exe_ctx, wrapper_struct_addr, error_stream);
+    }
+    else
+    {
+        m_print_object_caller_up->WriteFunctionArguments(exe_ctx,
+                                                         wrapper_struct_addr,
+                                                         arg_value_list,
+                                                         error_stream);
+    }
+
+    
 
     EvaluateExpressionOptions options;
     options.SetUnwindOnError(true);
@@ -153,11 +178,11 @@ AppleObjCRuntime::GetObjectDescription (Stream &strm, Value &value, ExecutionCon
     options.SetIgnoreBreakpoints(true);
     options.SetTimeoutUsec(PO_FUNCTION_TIMEOUT_USEC);
     
-    ExpressionResults results = func.ExecuteFunction (exe_ctx, 
-                                                     &wrapper_struct_addr,
-                                                     options,
-                                                     error_stream, 
-                                                     ret);
+    ExpressionResults results = m_print_object_caller_up->ExecuteFunction (exe_ctx,
+                                                                           &wrapper_struct_addr,
+                                                                           options,
+                                                                           error_stream,
+                                                                           ret);
     if (results != eExpressionCompleted)
     {
         strm.Printf("Error evaluating Print Object function: %d.\n", results);
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
index f8f73bae865..424058ee0b7 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.h
@@ -20,7 +20,6 @@
 #include "lldb/lldb-private.h"
 #include "lldb/Target/LanguageRuntime.h"
 #include "lldb/Target/ObjCLanguageRuntime.h"
-#include "lldb/Core/ValueObject.h"
 #include "AppleObjCTrampolineHandler.h"
 #include "AppleThreadPlanStepThroughObjCTrampoline.h"
 
@@ -31,7 +30,7 @@ class AppleObjCRuntime :
 {
 public:
     
-    virtual ~AppleObjCRuntime() { }
+    virtual ~AppleObjCRuntime();
     
     // These are generic runtime functions:
     bool
@@ -127,6 +126,7 @@ protected:
     std::unique_ptr<lldb_private::AppleObjCTrampolineHandler> m_objc_trampoline_handler_ap;
     lldb::BreakpointSP m_objc_exception_bp_sp;
     lldb::ModuleWP m_objc_module_wp;
+    std::unique_ptr<FunctionCaller>  m_print_object_caller_up;
     
     llvm::Optional<uint32_t> m_Foundation_major;
 
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
index 17aa03e4a64..85729e827f5 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.cpp
@@ -21,8 +21,8 @@
 #include "lldb/Core/PluginManager.h"
 #include "lldb/Core/Scalar.h"
 #include "lldb/Core/StreamString.h"
-#include "lldb/Expression/ClangFunction.h"
-#include "lldb/Expression/ClangUtilityFunction.h"
+#include "lldb/Expression/FunctionCaller.h"
+#include "lldb/Expression/UtilityFunction.h"
 #include "lldb/Symbol/ClangASTContext.h"
 #include "lldb/Symbol/Symbol.h"
 #include "lldb/Target/ExecutionContext.h"
@@ -143,7 +143,7 @@ struct BufStruct {
     char contents[2048];
 };
 
-ClangUtilityFunction *
+UtilityFunction *
 AppleObjCRuntimeV1::CreateObjectChecker(const char *name)
 {
     std::unique_ptr<BufStruct> buf(new BufStruct);
@@ -170,7 +170,8 @@ AppleObjCRuntimeV1::CreateObjectChecker(const char *name)
                     "}                                                                      \n",
                     name) < (int)sizeof(buf->contents));
 
-    return new ClangUtilityFunction(buf->contents, name);
+    Error error;
+    return GetTargetRef().GetUtilityFunctionForLanguage(buf->contents, eLanguageTypeObjC, name, error);
 }
 
 AppleObjCRuntimeV1::ClassDescriptorV1::ClassDescriptorV1 (ValueObject &isa_pointer)
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h
index f98f065f6a7..73e8607286f 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV1.h
@@ -102,7 +102,7 @@ public:
                               TypeAndOrName &class_type_or_name, 
                               Address &address);
 
-    virtual ClangUtilityFunction *
+    virtual UtilityFunction *
     CreateObjectChecker (const char *);
 
     //------------------------------------------------------------------
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
index 4817d57a353..ac643064415 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.cpp
@@ -28,8 +28,8 @@
 #include "lldb/Core/StreamString.h"
 #include "lldb/Core/Timer.h"
 #include "lldb/Core/ValueObjectVariable.h"
-#include "lldb/Expression/ClangFunction.h"
-#include "lldb/Expression/ClangUtilityFunction.h"
+#include "lldb/Expression/FunctionCaller.h"
+#include "lldb/Expression/UtilityFunction.h"
 #include "lldb/Host/StringConvert.h"
 #include "lldb/Interpreter/CommandObject.h"
 #include "lldb/Interpreter/CommandObjectMultiword.h"
@@ -348,11 +348,9 @@ ExtractRuntimeGlobalSymbol (Process* process,
 AppleObjCRuntimeV2::AppleObjCRuntimeV2 (Process *process,
                                         const ModuleSP &objc_module_sp) :
     AppleObjCRuntime (process),
-    m_get_class_info_function(),
     m_get_class_info_code(),
     m_get_class_info_args (LLDB_INVALID_ADDRESS),
     m_get_class_info_args_mutex (Mutex::eMutexTypeNormal),
-    m_get_shared_cache_class_info_function(),
     m_get_shared_cache_class_info_code(),
     m_get_shared_cache_class_info_args (LLDB_INVALID_ADDRESS),
     m_get_shared_cache_class_info_args_mutex (Mutex::eMutexTypeNormal),
@@ -722,7 +720,7 @@ AppleObjCRuntimeV2::CreateExceptionResolver (Breakpoint *bkpt, bool catch_bp, bo
     return resolver_sp;
 }
 
-ClangUtilityFunction *
+UtilityFunction *
 AppleObjCRuntimeV2::CreateObjectChecker(const char *name)
 {
     char check_function_code[2048];
@@ -780,7 +778,8 @@ AppleObjCRuntimeV2::CreateObjectChecker(const char *name)
     
     assert (len < (int)sizeof(check_function_code));
 
-    return new ClangUtilityFunction(check_function_code, name);
+    Error error;
+    return GetTargetRef().GetUtilityFunctionForLanguage(check_function_code, eLanguageTypeObjC, name, error);
 }
 
 size_t
@@ -1248,75 +1247,74 @@ AppleObjCRuntimeV2::UpdateISAToDescriptorMapDynamic(RemoteNXMapTable &hash_table
     CompilerType clang_uint32_t_type = ast->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 32);
     CompilerType clang_void_pointer_type = ast->GetBasicType(eBasicTypeVoid).GetPointerType();
     
+    ValueList arguments;
+    FunctionCaller *get_class_info_function = nullptr;
+
     if (!m_get_class_info_code.get())
     {
-        m_get_class_info_code.reset (new ClangUtilityFunction (g_get_dynamic_class_info_body,
-                                                               g_get_dynamic_class_info_name));
-        
-        errors.Clear();
-        
-        if (!m_get_class_info_code->Install(errors, exe_ctx))
+        Error error;
+        m_get_class_info_code.reset (GetTargetRef().GetUtilityFunctionForLanguage (g_get_dynamic_class_info_body,
+                                                                                   eLanguageTypeObjC,
+                                                                                   g_get_dynamic_class_info_name,
+                                                                                   error));
+        if (error.Fail())
         {
             if (log)
-                log->Printf ("Failed to install implementation lookup: %s.", errors.GetData());
+                log->Printf ("Failed to get Utility Function for implementation lookup: %s", error.AsCString());
             m_get_class_info_code.reset();
         }
-    }
-    
-    if (m_get_class_info_code.get())
-        function_address.SetOffset(m_get_class_info_code->StartAddress());
-    else
-        return false;
-    
-    ValueList arguments;
-    
-    // Next make the runner function for our implementation utility function.
-    if (!m_get_class_info_function.get())
-    {
+        else
+        {
+            errors.Clear();
+            
+            if (!m_get_class_info_code->Install(errors, exe_ctx))
+            {
+                if (log)
+                    log->Printf ("Failed to install implementation lookup: %s.", errors.GetData());
+                m_get_class_info_code.reset();
+            }
+        }
+        if (!m_get_class_info_code.get())
+            return false;
+        
+        // Next make the runner function for our implementation utility function.
         Value value;
         value.SetValueType (Value::eValueTypeScalar);
-//        value.SetContext (Value::eContextTypeClangType, clang_void_pointer_type);
         value.SetCompilerType (clang_void_pointer_type);
         arguments.PushValue (value);
         arguments.PushValue (value);
         
         value.SetValueType (Value::eValueTypeScalar);
-//        value.SetContext (Value::eContextTypeClangType, clang_uint32_t_type);
         value.SetCompilerType (clang_uint32_t_type);
         arguments.PushValue (value);
         
-        m_get_class_info_function.reset(new ClangFunction (*m_process,
-                                                           clang_uint32_t_type,
-                                                           function_address,
-                                                           arguments,
-                                                           "objc-v2-isa-to-descriptor"));
-        
-        if (m_get_class_info_function.get() == NULL)
-            return false;
-        
-        errors.Clear();
+        get_class_info_function = m_get_class_info_code->MakeFunctionCaller(clang_uint32_t_type,
+                                                                            arguments,
+                                                                            error);
         
-        unsigned num_errors = m_get_class_info_function->CompileFunction(errors);
-        if (num_errors)
+        if (error.Fail())
         {
             if (log)
-                log->Printf ("Error compiling function: \"%s\".", errors.GetData());
+                log->Printf("Failed to make function caller for implementation lookup: %s.", error.AsCString());
             return false;
         }
-        
-        errors.Clear();
-        
-        if (!m_get_class_info_function->WriteFunctionWrapper(exe_ctx, errors))
+    }
+    else
+    {
+        get_class_info_function = m_get_class_info_code->GetFunctionCaller();
+        if (!get_class_info_function)
         {
             if (log)
-                log->Printf ("Error Inserting function: \"%s\".", errors.GetData());
+                log->Printf ("Failed to get implementation lookup function caller: %s.", errors.GetData());
             return false;
         }
+        arguments = get_class_info_function->GetArgumentValues();
     }
-    else
-    {
-        arguments = m_get_class_info_function->GetArgumentValues ();
-    }
+    
+    
+    
+    
+    errors.Clear();
     
     const uint32_t class_info_byte_size = addr_size + 4;
     const uint32_t class_infos_byte_size = num_classes * class_info_byte_size;
@@ -1339,9 +1337,8 @@ AppleObjCRuntimeV2::UpdateISAToDescriptorMapDynamic(RemoteNXMapTable &hash_table
     errors.Clear();
     
     // Write our function arguments into the process so we can run our function
-    if (m_get_class_info_function->WriteFunctionArguments (exe_ctx,
+    if (get_class_info_function->WriteFunctionArguments (exe_ctx,
                                                            m_get_class_info_args,
-                                                           function_address,
                                                            arguments,
                                                            errors))
     {
@@ -1361,11 +1358,11 @@ AppleObjCRuntimeV2::UpdateISAToDescriptorMapDynamic(RemoteNXMapTable &hash_table
         errors.Clear();
         
         // Run the function
-        ExpressionResults results = m_get_class_info_function->ExecuteFunction (exe_ctx,
-                                                                               &m_get_class_info_args,
-                                                                               options,
-                                                                               errors,
-                                                                               return_value);
+        ExpressionResults results = get_class_info_function->ExecuteFunction (exe_ctx,
+                                                                              &m_get_class_info_args,
+                                                                              options,
+                                                                              errors,
+                                                                              return_value);
         
         if (results == eExpressionCompleted)
         {
@@ -1502,31 +1499,38 @@ AppleObjCRuntimeV2::UpdateISAToDescriptorMapSharedCache()
     CompilerType clang_uint32_t_type = ast->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 32);
     CompilerType clang_void_pointer_type = ast->GetBasicType(eBasicTypeVoid).GetPointerType();
     
+    ValueList arguments;
+    FunctionCaller *get_shared_cache_class_info_function = nullptr;
+    
     if (!m_get_shared_cache_class_info_code.get())
     {
-        m_get_shared_cache_class_info_code.reset (new ClangUtilityFunction (g_get_shared_cache_class_info_body,
-                                                                            g_get_shared_cache_class_info_name));
-        
-        errors.Clear();
-        
-        if (!m_get_shared_cache_class_info_code->Install(errors, exe_ctx))
+        Error error;
+        m_get_shared_cache_class_info_code.reset (GetTargetRef().GetUtilityFunctionForLanguage (g_get_shared_cache_class_info_body,
+                                                                                                eLanguageTypeObjC,
+                                                                                                g_get_shared_cache_class_info_name,
+                                                                                                error));
+        if (error.Fail())
         {
             if (log)
-                log->Printf ("Failed to install implementation lookup: %s.", errors.GetData());
+                log->Printf ("Failed to get Utility function for implementation lookup: %s.", error.AsCString());
             m_get_shared_cache_class_info_code.reset();
         }
-    }
-    
-    if (m_get_shared_cache_class_info_code.get())
-        function_address.SetOffset(m_get_shared_cache_class_info_code->StartAddress());
-    else
-        return DescriptorMapUpdateResult::Fail();
-    
-    ValueList arguments;
+        else
+        {
+            errors.Clear();
+            
+            if (!m_get_shared_cache_class_info_code->Install(errors, exe_ctx))
+            {
+                if (log)
+                    log->Printf ("Failed to install implementation lookup: %s.", errors.GetData());
+                m_get_shared_cache_class_info_code.reset();
+            }
+        }
+        
+        if (!m_get_shared_cache_class_info_code.get())
+            return DescriptorMapUpdateResult::Fail();
     
-    // Next make the runner function for our implementation utility function.
-    if (!m_get_shared_cache_class_info_function.get())
-    {
+        // Next make the function caller for our implementation utility function.
         Value value;
         value.SetValueType (Value::eValueTypeScalar);
         //value.SetContext (Value::eContextTypeClangType, clang_void_pointer_type);
@@ -1539,39 +1543,24 @@ AppleObjCRuntimeV2::UpdateISAToDescriptorMapSharedCache()
         value.SetCompilerType (clang_uint32_t_type);
         arguments.PushValue (value);
         
-        m_get_shared_cache_class_info_function.reset(new ClangFunction (*m_process,
-                                                                        clang_uint32_t_type,
-                                                                        function_address,
-                                                                        arguments,
-                                                                        "objc-isa-to-descriptor-shared-cache"));
-        
-        if (m_get_shared_cache_class_info_function.get() == NULL)
-            return DescriptorMapUpdateResult::Fail();
-        
-        errors.Clear();
-        
-        unsigned num_errors = m_get_shared_cache_class_info_function->CompileFunction(errors);
-        if (num_errors)
-        {
-            if (log)
-                log->Printf ("Error compiling function: \"%s\".", errors.GetData());
-            return DescriptorMapUpdateResult::Fail();
-        }
-        
-        errors.Clear();
+        get_shared_cache_class_info_function = m_get_shared_cache_class_info_code->MakeFunctionCaller(clang_uint32_t_type,
+                                                                                                      arguments,
+                                                                                                      error);
         
-        if (!m_get_shared_cache_class_info_function->WriteFunctionWrapper(exe_ctx, errors))
-        {
-            if (log)
-                log->Printf ("Error Inserting function: \"%s\".", errors.GetData());
+        if (get_shared_cache_class_info_function == nullptr)
             return DescriptorMapUpdateResult::Fail();
-        }
+    
     }
     else
     {
-        arguments = m_get_shared_cache_class_info_function->GetArgumentValues ();
+        get_shared_cache_class_info_function = m_get_shared_cache_class_info_code->GetFunctionCaller();
+        if (get_shared_cache_class_info_function == nullptr)
+            return DescriptorMapUpdateResult::Fail();
+        arguments = get_shared_cache_class_info_function->GetArgumentValues();
     }
     
+    errors.Clear();
+    
     const uint32_t class_info_byte_size = addr_size + 4;
     const uint32_t class_infos_byte_size = num_classes * class_info_byte_size;
     lldb::addr_t class_infos_addr = process->AllocateMemory (class_infos_byte_size,
@@ -1594,11 +1583,10 @@ AppleObjCRuntimeV2::UpdateISAToDescriptorMapSharedCache()
     errors.Clear();
     
     // Write our function arguments into the process so we can run our function
-    if (m_get_shared_cache_class_info_function->WriteFunctionArguments (exe_ctx,
-                                                                        m_get_shared_cache_class_info_args,
-                                                                        function_address,
-                                                                        arguments,
-                                                                        errors))
+    if (get_shared_cache_class_info_function->WriteFunctionArguments (exe_ctx,
+                                                                      m_get_shared_cache_class_info_args,
+                                                                      arguments,
+                                                                      errors))
     {
         EvaluateExpressionOptions options;
         options.SetUnwindOnError(true);
@@ -1616,11 +1604,11 @@ AppleObjCRuntimeV2::UpdateISAToDescriptorMapSharedCache()
         errors.Clear();
         
         // Run the function
-        ExpressionResults results = m_get_shared_cache_class_info_function->ExecuteFunction (exe_ctx,
-                                                                                            &m_get_shared_cache_class_info_args,
-                                                                                            options,
-                                                                                            errors,
-                                                                                            return_value);
+        ExpressionResults results = get_shared_cache_class_info_function->ExecuteFunction (exe_ctx,
+                                                                                           &m_get_shared_cache_class_info_args,
+                                                                                           options,
+                                                                                           errors,
+                                                                                           return_value);
         
         if (results == eExpressionCompleted)
         {
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
index 6d981f72d8c..feaf9d4d6f0 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntimeV2.h
@@ -39,7 +39,7 @@ public:
                               TypeAndOrName &class_type_or_name, 
                               Address &address);
     
-    virtual ClangUtilityFunction *
+    virtual UtilityFunction *
     CreateObjectChecker (const char *);
 
 
@@ -299,22 +299,20 @@ private:
     
     friend class ClassDescriptorV2;
 
-    std::unique_ptr<ClangFunction>            m_get_class_info_function;
-    std::unique_ptr<ClangUtilityFunction>     m_get_class_info_code;
+    std::unique_ptr<UtilityFunction>        m_get_class_info_code;
     lldb::addr_t                            m_get_class_info_args;
     Mutex                                   m_get_class_info_args_mutex;
 
-    std::unique_ptr<ClangFunction>            m_get_shared_cache_class_info_function;
-    std::unique_ptr<ClangUtilityFunction>     m_get_shared_cache_class_info_code;
+    std::unique_ptr<UtilityFunction>        m_get_shared_cache_class_info_code;
     lldb::addr_t                            m_get_shared_cache_class_info_args;
     Mutex                                   m_get_shared_cache_class_info_args_mutex;
 
-    std::unique_ptr<DeclVendor>               m_decl_vendor_ap;
+    std::unique_ptr<DeclVendor>             m_decl_vendor_ap;
     lldb::addr_t                            m_isa_hash_table_ptr;
     HashTableSignature                      m_hash_signature;
     bool                                    m_has_object_getClass;
     bool                                    m_loaded_objc_opt;
-    std::unique_ptr<NonPointerISACache>       m_non_pointer_isa_cache_ap;
+    std::unique_ptr<NonPointerISACache>     m_non_pointer_isa_cache_ap;
     std::unique_ptr<TaggedPointerVendor>    m_tagged_pointer_vendor_ap;
     EncodingToTypeSP                        m_encoding_to_type_sp;
     bool                                    m_noclasses_warning_emitted;
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCTrampolineHandler.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCTrampolineHandler.cpp
index db5b7f0a406..d38a076ad5d 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCTrampolineHandler.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCTrampolineHandler.cpp
@@ -22,9 +22,9 @@
 #include "lldb/Core/Module.h"
 #include "lldb/Core/StreamFile.h"
 #include "lldb/Core/Value.h"
-#include "lldb/Expression/ClangExpression.h"
-#include "lldb/Expression/ClangFunction.h"
-#include "lldb/Expression/ClangUtilityFunction.h"
+#include "lldb/Expression/UserExpression.h"
+#include "lldb/Expression/FunctionCaller.h"
+#include "lldb/Expression/UtilityFunction.h"
 #include "lldb/Host/FileSpec.h"
 #include "lldb/Symbol/ClangASTContext.h"
 #include "lldb/Symbol/Symbol.h"
@@ -741,10 +741,10 @@ lldb::addr_t
 AppleObjCTrampolineHandler::SetupDispatchFunction (Thread &thread, ValueList &dispatch_values)
 {
     ExecutionContext exe_ctx (thread.shared_from_this());
-    Address impl_code_address;
     StreamString errors;
     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
     lldb::addr_t args_addr = LLDB_INVALID_ADDRESS;
+    FunctionCaller *impl_function_caller = nullptr;
 
     // Scope for mutex locker:
     {
@@ -752,38 +752,23 @@ AppleObjCTrampolineHandler::SetupDispatchFunction (Thread &thread, ValueList &di
         
         // First stage is to make the ClangUtility to hold our injected function:
 
-    #define USE_BUILTIN_FUNCTION 0  // Define this to 1 and we will use the get_implementation function found in the target.
-                        // This is useful for debugging additions to the get_impl function 'cause you don't have
-                        // to bother with string-ifying the code into g_lookup_implementation_function_code.
-        
-        if (USE_BUILTIN_FUNCTION)
-        {
-            ConstString our_utility_function_name("__lldb_objc_find_implementation_for_selector");
-            SymbolContextList sc_list;
-            
-            exe_ctx.GetTargetRef().GetImages().FindSymbolsWithNameAndType (our_utility_function_name, eSymbolTypeCode, sc_list);
-            if (sc_list.GetSize() == 1)
-            {
-                SymbolContext sc;
-                sc_list.GetContextAtIndex(0, sc);
-                if (sc.symbol != NULL)
-                    impl_code_address = sc.symbol->GetAddress();
-                    
-                //lldb::addr_t addr = impl_code_address.GetOpcodeLoadAddress (exe_ctx.GetTargetPtr());
-                //printf ("Getting address for our_utility_function: 0x%" PRIx64 ".\n", addr);
-            }
-            else
-            {
-                //printf ("Could not find implementation function address.\n");
-                return args_addr;
-            }
-        }
-        else if (!m_impl_code.get())
+        if (!m_impl_code.get())
         {
             if (g_lookup_implementation_function_code != NULL)
             {
-                m_impl_code.reset (new ClangUtilityFunction (g_lookup_implementation_function_code,
-                                                             g_lookup_implementation_function_name));
+                Error error;
+                m_impl_code.reset (exe_ctx.GetTargetRef().GetUtilityFunctionForLanguage (g_lookup_implementation_function_code,
+                                                                                         eLanguageTypeObjC,
+                                                                                         g_lookup_implementation_function_name,
+                                                                                         error));
+                if (error.Fail())
+                {
+                    if (log)
+                        log->Printf ("Failed to get Utility Function for implementation lookup: %s.", error.AsCString());
+                    m_impl_code.reset();
+                    return args_addr;
+                }
+                
                 if (!m_impl_code->Install(errors, exe_ctx))
                 {
                     if (log)
@@ -800,43 +785,26 @@ AppleObjCTrampolineHandler::SetupDispatchFunction (Thread &thread, ValueList &di
                 return LLDB_INVALID_ADDRESS;
             }
             
-            impl_code_address.Clear();
-            impl_code_address.SetOffset(m_impl_code->StartAddress());
-        }
-        else
-        {
-            impl_code_address.Clear();
-            impl_code_address.SetOffset(m_impl_code->StartAddress());
-        }
 
-        // Next make the runner function for our implementation utility function.
-        if (!m_impl_function.get())
-        {
+            // Next make the runner function for our implementation utility function.
             ClangASTContext *clang_ast_context = thread.GetProcess()->GetTarget().GetScratchClangASTContext();
             CompilerType clang_void_ptr_type = clang_ast_context->GetBasicType(eBasicTypeVoid).GetPointerType();
-            m_impl_function.reset(new ClangFunction (thread,
-                                                     clang_void_ptr_type,
-                                                     impl_code_address,
-                                                     dispatch_values,
-                                                     "objc-dispatch-lookup"));
+            Error error;
             
-            errors.Clear();        
-            unsigned num_errors = m_impl_function->CompileFunction(errors);
-            if (num_errors)
+            impl_function_caller = m_impl_code->MakeFunctionCaller(clang_void_ptr_type,
+                                                                   dispatch_values,
+                                                                   error);
+            if (error.Fail())
             {
                 if (log)
-                    log->Printf ("Error compiling function: \"%s\".", errors.GetData());
-                return args_addr;
-            }
-            
-            errors.Clear();
-            if (!m_impl_function->WriteFunctionWrapper(exe_ctx, errors))
-            {
-                if (log)
-                    log->Printf ("Error Inserting function: \"%s\".", errors.GetData());
+                    log->Printf ("Error getting function caller for dispatch lookup: \"%s\".", error.AsCString());
                 return args_addr;
             }
         }
+        else
+        {
+            impl_function_caller = m_impl_code->GetFunctionCaller();
+        }
     }
     
     errors.Clear();
@@ -845,7 +813,7 @@ AppleObjCTrampolineHandler::SetupDispatchFunction (Thread &thread, ValueList &di
     // if other threads were calling into here, but actually it isn't because we allocate a new args structure for
     // this call by passing args_addr = LLDB_INVALID_ADDRESS...
 
-    if (!m_impl_function->WriteFunctionArguments (exe_ctx, args_addr, impl_code_address, dispatch_values, errors))
+    if (impl_function_caller->WriteFunctionArguments (exe_ctx, args_addr, dispatch_values, errors))
     {
         if (log)
             log->Printf ("Error writing function arguments: \"%s\".", errors.GetData());
@@ -1169,8 +1137,8 @@ AppleObjCTrampolineHandler::GetStepThroughDispatchPlan (Thread &thread, bool sto
     return ret_plan_sp;
 }
 
-ClangFunction *
-AppleObjCTrampolineHandler::GetLookupImplementationWrapperFunction ()
+FunctionCaller *
+AppleObjCTrampolineHandler::GetLookupImplementationFunctionCaller ()
 {
-    return m_impl_function.get();
+    return m_impl_code->GetFunctionCaller();
 }
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCTrampolineHandler.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCTrampolineHandler.h
index c9d0e19ed2b..0ddb540439d 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCTrampolineHandler.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCTrampolineHandler.h
@@ -35,8 +35,8 @@ public:
     GetStepThroughDispatchPlan (Thread &thread, 
                                 bool stop_others);
     
-    ClangFunction *
-    GetLookupImplementationWrapperFunction ();
+    FunctionCaller *
+    GetLookupImplementationFunctionCaller ();
     
     bool 
     AddrIsMsgForward (lldb::addr_t addr) const
@@ -198,8 +198,7 @@ private:
     MsgsendMap m_msgSend_map;
     lldb::ProcessWP m_process_wp;
     lldb::ModuleSP m_objc_module_sp;
-    std::unique_ptr<ClangFunction> m_impl_function;
-    std::unique_ptr<ClangUtilityFunction> m_impl_code;
+    std::unique_ptr<UtilityFunction> m_impl_code;
     Mutex m_impl_function_mutex;
     lldb::addr_t m_impl_fn_addr;
     lldb::addr_t m_impl_stret_fn_addr;
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleThreadPlanStepThroughObjCTrampoline.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleThreadPlanStepThroughObjCTrampoline.cpp
index fe364faefe3..285786a09db 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleThreadPlanStepThroughObjCTrampoline.cpp
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleThreadPlanStepThroughObjCTrampoline.cpp
@@ -15,8 +15,8 @@
 #include "AppleObjCTrampolineHandler.h"
 #include "lldb/Target/Process.h"
 #include "lldb/Target/Thread.h"
-#include "lldb/Expression/ClangExpression.h"
-#include "lldb/Expression/ClangFunction.h"
+#include "lldb/Expression/FunctionCaller.h"
+#include "lldb/Expression/UtilityFunction.h"
 #include "lldb/Target/ExecutionContext.h"
 #include "lldb/Target/ObjCLanguageRuntime.h"
 #include "lldb/Target/ThreadPlanRunToAddress.h"
@@ -67,11 +67,11 @@ AppleThreadPlanStepThroughObjCTrampoline::DidPush ()
 {
     // Setting up the memory space for the called function text might require allocations,
     // i.e. a nested function call.  This needs to be done as a PreResumeAction.
-    m_thread.GetProcess()->AddPreResumeAction (PreResumeInitializeClangFunction, (void *) this);
+    m_thread.GetProcess()->AddPreResumeAction (PreResumeInitializeFunctionCaller, (void *) this);
 }
 
 bool
-AppleThreadPlanStepThroughObjCTrampoline::InitializeClangFunction ()
+AppleThreadPlanStepThroughObjCTrampoline::InitializeFunctionCaller ()
 {
     if (!m_func_sp)
     {
@@ -82,7 +82,7 @@ AppleThreadPlanStepThroughObjCTrampoline::InitializeClangFunction ()
         {
             return false;
         }
-        m_impl_function = m_trampoline_handler->GetLookupImplementationWrapperFunction();
+        m_impl_function = m_trampoline_handler->GetLookupImplementationFunctionCaller();
         ExecutionContext exc_ctx;
         EvaluateExpressionOptions options;
         options.SetUnwindOnError(true);
@@ -100,10 +100,10 @@ AppleThreadPlanStepThroughObjCTrampoline::InitializeClangFunction ()
 }
 
 bool
-AppleThreadPlanStepThroughObjCTrampoline::PreResumeInitializeClangFunction(void *void_myself)
+AppleThreadPlanStepThroughObjCTrampoline::PreResumeInitializeFunctionCaller(void *void_myself)
 {
     AppleThreadPlanStepThroughObjCTrampoline *myself = static_cast<AppleThreadPlanStepThroughObjCTrampoline *>(void_myself);
-    return myself->InitializeClangFunction();
+    return myself->InitializeFunctionCaller();
 }
 
 void
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleThreadPlanStepThroughObjCTrampoline.h b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleThreadPlanStepThroughObjCTrampoline.h
index 253190991ce..2ad181e553f 100644
--- a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleThreadPlanStepThroughObjCTrampoline.h
+++ b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleThreadPlanStepThroughObjCTrampoline.h
@@ -66,7 +66,7 @@ public:
     DidPush();
     
     static bool
-    PreResumeInitializeClangFunction(void *myself);
+    PreResumeInitializeFunctionCaller(void *myself);
 
     virtual bool
     WillStop();
@@ -82,7 +82,7 @@ protected:
 	
 private:
     bool
-    InitializeClangFunction ();
+    InitializeFunctionCaller ();
 
 	//------------------------------------------------------------------
 	// For AppleThreadPlanStepThroughObjCTrampoline only
@@ -96,7 +96,7 @@ private:
     lldb::ThreadPlanSP m_func_sp;       // This is the function call plan.  We fill it at start, then set it
                                         // to NULL when this plan is done.  That way we know to go to:
     lldb::ThreadPlanSP m_run_to_sp;     // The plan that runs to the target.
-    ClangFunction *m_impl_function;  // This is a pointer to a impl function that 
+    FunctionCaller *m_impl_function;  // This is a pointer to a impl function that
                                      // is owned by the client that pushes this plan.
     bool m_stop_others;
 };