vendor/lldb/lldb-release_39-r276489

16 files changed, 1739 insertions, 655 deletions

diff --git a/source/Expression/CMakeLists.txt b/source/Expression/CMakeLists.txt
index 52392f13319aa..48e67888e436d 100644
--- a/source/Expression/CMakeLists.txt
+++ b/source/Expression/CMakeLists.txt
@@ -1,4 +1,5 @@
 add_lldb_library(lldbExpression
+  DiagnosticManager.cpp
   DWARFExpression.cpp
   Expression.cpp
   ExpressionSourceCode.cpp
diff --git a/source/Expression/DWARFExpression.cpp b/source/Expression/DWARFExpression.cpp
index ebcc284603958..b81d60e9b065b 100644
--- a/source/Expression/DWARFExpression.cpp
+++ b/source/Expression/DWARFExpression.cpp
@@ -1003,7 +1003,128 @@ DWARFExpression::Update_DW_OP_addr (lldb::addr_t file_addr)
 }
 
 bool
-DWARFExpression::LocationListContainsAddress (lldb::addr_t loclist_base_addr, lldb::addr_t addr) const
+DWARFExpression::ContainsThreadLocalStorage() const
+{
+    // We are assuming for now that any thread local variable will not
+    // have a location list. This has been true for all thread local
+    // variables we have seen so far produced by any compiler.
+    if (IsLocationList())
+        return false;
+    lldb::offset_t offset = 0;
+    while (m_data.ValidOffset(offset))
+    {
+        const uint8_t op = m_data.GetU8(&offset);
+
+        if (op == DW_OP_form_tls_address || op == DW_OP_GNU_push_tls_address)
+            return true;
+        const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op);
+        if (op_arg_size == LLDB_INVALID_OFFSET)
+            return false;
+        else
+            offset += op_arg_size;
+    }
+    return false;
+}
+bool
+DWARFExpression::LinkThreadLocalStorage(
+    lldb::ModuleSP new_module_sp, std::function<lldb::addr_t(lldb::addr_t file_addr)> const &link_address_callback)
+{
+    // We are assuming for now that any thread local variable will not
+    // have a location list. This has been true for all thread local
+    // variables we have seen so far produced by any compiler.
+    if (IsLocationList())
+        return false;
+
+    const uint32_t addr_byte_size = m_data.GetAddressByteSize();
+    // We have to make a copy of the data as we don't know if this
+    // data is from a read only memory mapped buffer, so we duplicate
+    // all of the data first, then modify it, and if all goes well,
+    // we then replace the data for this expression
+
+    // So first we copy the data into a heap buffer
+    std::shared_ptr<DataBufferHeap> heap_data_sp(new DataBufferHeap(m_data.GetDataStart(), m_data.GetByteSize()));
+
+    // Make en encoder so we can write the address into the buffer using
+    // the correct byte order (endianness)
+    DataEncoder encoder(heap_data_sp->GetBytes(), heap_data_sp->GetByteSize(), m_data.GetByteOrder(), addr_byte_size);
+
+    lldb::offset_t offset = 0;
+    lldb::offset_t const_offset = 0;
+    lldb::addr_t const_value = 0;
+    size_t const_byte_size = 0;
+    while (m_data.ValidOffset(offset))
+    {
+        const uint8_t op = m_data.GetU8(&offset);
+
+        bool decoded_data = false;
+        switch (op)
+        {
+            case DW_OP_const4u:
+                // Remember the const offset in case we later have a DW_OP_form_tls_address
+                // or DW_OP_GNU_push_tls_address
+                const_offset = offset;
+                const_value = m_data.GetU32(&offset);
+                decoded_data = true;
+                const_byte_size = 4;
+                break;
+
+            case DW_OP_const8u:
+                // Remember the const offset in case we later have a DW_OP_form_tls_address
+                // or DW_OP_GNU_push_tls_address
+                const_offset = offset;
+                const_value = m_data.GetU64(&offset);
+                decoded_data = true;
+                const_byte_size = 8;
+                break;
+
+            case DW_OP_form_tls_address:
+            case DW_OP_GNU_push_tls_address:
+                // DW_OP_form_tls_address and DW_OP_GNU_push_tls_address must be preceded by
+                // a file address on the stack. We assume that DW_OP_const4u or DW_OP_const8u
+                // is used for these values, and we check that the last opcode we got before
+                // either of these was DW_OP_const4u or DW_OP_const8u. If so, then we can link
+                // the value accodingly. For Darwin, the value in the DW_OP_const4u or
+                // DW_OP_const8u is the file address of a structure that contains a function
+                // pointer, the pthread key and the offset into the data pointed to by the
+                // pthread key. So we must link this address and also set the module of this
+                // expression to the new_module_sp so we can resolve the file address correctly
+                if (const_byte_size > 0)
+                {
+                    lldb::addr_t linked_file_addr = link_address_callback(const_value);
+                    if (linked_file_addr == LLDB_INVALID_ADDRESS)
+                        return false;
+                    // Replace the address in the new buffer
+                    if (encoder.PutMaxU64(const_offset, const_byte_size, linked_file_addr) == UINT32_MAX)
+                        return false;
+                }
+                break;
+
+            default:
+                const_offset = 0;
+                const_value = 0;
+                const_byte_size = 0;
+                break;
+        }
+
+        if (!decoded_data)
+        {
+            const offset_t op_arg_size = GetOpcodeDataSize(m_data, offset, op);
+            if (op_arg_size == LLDB_INVALID_OFFSET)
+                return false;
+            else
+                offset += op_arg_size;
+        }
+    }
+
+    // If we linked the TLS address correctly, update the module so that when the expression
+    // is evaluated it can resolve the file address to a load address and read the TLS data
+    m_module_wp = new_module_sp;
+    m_data.SetData(heap_data_sp);
+    return true;
+}
+
+bool
+DWARFExpression::LocationListContainsAddress(lldb::addr_t loclist_base_addr, lldb::addr_t addr) const
 {
     if (addr == LLDB_INVALID_ADDRESS)
         return false;
@@ -1108,12 +1229,21 @@ DWARFExpression::Evaluate
     ClangExpressionDeclMap *decl_map,
     lldb::addr_t loclist_base_load_addr,
     const Value* initial_value_ptr,
+    const Value* object_address_ptr,
     Value& result,
     Error *error_ptr
 ) const
 {
     ExecutionContext exe_ctx (exe_scope);
-    return Evaluate(&exe_ctx, expr_locals, decl_map, NULL, loclist_base_load_addr, initial_value_ptr, result, error_ptr);
+    return Evaluate(&exe_ctx,
+                    expr_locals,
+                    decl_map,
+                    nullptr,
+                    loclist_base_load_addr,
+                    initial_value_ptr,
+                    object_address_ptr,
+                    result,
+                    error_ptr);
 }
 
 bool
@@ -1125,6 +1255,7 @@ DWARFExpression::Evaluate
     RegisterContext *reg_ctx,
     lldb::addr_t loclist_base_load_addr,
     const Value* initial_value_ptr,
+    const Value* object_address_ptr,
     Value& result,
     Error *error_ptr
 ) const
@@ -1189,6 +1320,7 @@ DWARFExpression::Evaluate
                                                       length,
                                                       m_reg_kind,
                                                       initial_value_ptr,
+                                                      object_address_ptr,
                                                       result,
                                                       error_ptr);
                 }
@@ -1212,6 +1344,7 @@ DWARFExpression::Evaluate
                                       m_data.GetByteSize(),
                                       m_reg_kind,
                                       initial_value_ptr,
+                                      object_address_ptr,
                                       result,
                                       error_ptr);
 }
@@ -1232,6 +1365,7 @@ DWARFExpression::Evaluate
     const lldb::offset_t opcodes_length,
     const lldb::RegisterKind reg_kind,
     const Value* initial_value_ptr,
+    const Value* object_address_ptr,
     Value& result,
     Error *error_ptr
 )
@@ -1931,7 +2065,7 @@ DWARFExpression::Evaluate
             {
                 tmp = stack.back();
                 stack.pop_back();
-                stack.back().ResolveValue(exe_ctx) = stack.back().ResolveValue(exe_ctx) + tmp.ResolveValue(exe_ctx);
+                stack.back().GetScalar() += tmp.GetScalar();
             }
             break;
 
@@ -1952,8 +2086,8 @@ DWARFExpression::Evaluate
             {
                 const uint64_t uconst_value = opcodes.GetULEB128(&offset);
                 // Implicit conversion from a UINT to a Scalar...
-                stack.back().ResolveValue(exe_ctx) += uconst_value;
-                if (!stack.back().ResolveValue(exe_ctx).IsValid())
+                stack.back().GetScalar() += uconst_value;
+                if (!stack.back().GetScalar().IsValid())
                 {
                     if (error_ptr)
                         error_ptr->SetErrorString("DW_OP_plus_uconst failed.");
@@ -2689,9 +2823,15 @@ DWARFExpression::Evaluate
         // during user expression evaluation.
         //----------------------------------------------------------------------
         case DW_OP_push_object_address:
-            if (error_ptr)
-                error_ptr->SetErrorString ("Unimplemented opcode DW_OP_push_object_address.");
-            return false;
+            if (object_address_ptr)
+                stack.push_back(*object_address_ptr);
+            else
+            {
+                if (error_ptr)
+                    error_ptr->SetErrorString ("DW_OP_push_object_address used without specifying an object address");
+                return false;
+            }
+            break;
 
         //----------------------------------------------------------------------
         // OPCODE: DW_OP_call2
@@ -2826,18 +2966,17 @@ DWARFExpression::Evaluate
                 }
 
                 // Lookup the TLS block address for this thread and module.
-                addr_t tls_addr = thread->GetThreadLocalData (module_sp);
+                const addr_t tls_file_addr = stack.back().GetScalar().ULongLong(LLDB_INVALID_ADDRESS);
+                const addr_t tls_load_addr = thread->GetThreadLocalData(module_sp, tls_file_addr);
 
-                if (tls_addr == LLDB_INVALID_ADDRESS)
+                if (tls_load_addr == LLDB_INVALID_ADDRESS)
                 {
                     if (error_ptr)
                         error_ptr->SetErrorString ("No TLS data currently exists for this thread.");
                     return false;
                 }
 
-                // Convert the TLS offset into the absolute address.
-                Scalar tmp = stack.back().ResolveValue(exe_ctx);
-                stack.back() = tmp + tls_addr;
+                stack.back().GetScalar() = tls_load_addr;
                 stack.back().SetValueType (Value::eValueTypeLoadAddress);
             }
             break;
diff --git a/source/Expression/DiagnosticManager.cpp b/source/Expression/DiagnosticManager.cpp
new file mode 100644
index 0000000000000..5156ee38a67bf
--- /dev/null
+++ b/source/Expression/DiagnosticManager.cpp
@@ -0,0 +1,91 @@
+//===-- DiagnosticManager.cpp -----------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Expression/DiagnosticManager.h"
+
+#include "llvm/Support/ErrorHandling.h"
+
+#include "lldb/Core/Log.h"
+#include "lldb/Core/StreamString.h"
+
+using namespace lldb_private;
+
+void
+DiagnosticManager::Dump(Log *log)
+{
+    if (!log)
+        return;
+
+    std::string str = GetString();
+
+    // GetString() puts a separator after each diagnostic.
+    // We want to remove the last '\n' because log->PutCString will add one for us.
+
+    if (str.size() && str.back() == '\n')
+    {
+        str.pop_back();
+    }
+
+    log->PutCString(str.c_str());
+}
+
+static const char *
+StringForSeverity(DiagnosticSeverity severity)
+{
+    switch (severity)
+    {
+        // this should be exhaustive
+        case lldb_private::eDiagnosticSeverityError:
+            return "error: ";
+        case lldb_private::eDiagnosticSeverityWarning:
+            return "warning: ";
+        case lldb_private::eDiagnosticSeverityRemark:
+            return "";
+    }
+    llvm_unreachable("switch needs another case for DiagnosticSeverity enum");
+}
+
+std::string
+DiagnosticManager::GetString(char separator)
+{
+    std::string ret;
+
+    for (const Diagnostic *diagnostic : Diagnostics())
+    {
+        ret.append(StringForSeverity(diagnostic->GetSeverity()));
+        ret.append(diagnostic->GetMessage());
+        ret.push_back(separator);
+    }
+
+    return ret;
+}
+
+size_t
+DiagnosticManager::Printf(DiagnosticSeverity severity, const char *format, ...)
+{
+    StreamString ss;
+
+    va_list args;
+    va_start(args, format);
+    size_t result = ss.PrintfVarArg(format, args);
+    va_end(args);
+
+    AddDiagnostic(ss.GetData(), severity, eDiagnosticOriginLLDB);
+
+    return result;
+}
+
+size_t
+DiagnosticManager::PutCString(DiagnosticSeverity severity, const char *cstr)
+{
+    if (!cstr)
+        return 0;
+    AddDiagnostic(cstr, severity, eDiagnosticOriginLLDB);
+    return strlen(cstr);
+}
diff --git a/source/Expression/ExpressionSourceCode.cpp b/source/Expression/ExpressionSourceCode.cpp
index c4ab7a95d7a9a..2d41d1a8b449d 100644
--- a/source/Expression/ExpressionSourceCode.cpp
+++ b/source/Expression/ExpressionSourceCode.cpp
@@ -16,7 +16,9 @@
 #include "lldb/Symbol/DebugMacros.h"
 #include "lldb/Symbol/Block.h"
 #include "lldb/Symbol/TypeSystem.h"
+#include "lldb/Symbol/VariableList.h"
 #include "lldb/Target/ExecutionContext.h"
+#include "lldb/Target/Language.h"
 #include "lldb/Target/Platform.h"
 #include "lldb/Target/StackFrame.h"
 #include "lldb/Target/Target.h"
@@ -59,6 +61,9 @@ extern "C"
 }
 )";
 
+static const char *c_start_marker = "    /*LLDB_BODY_START*/\n    ";
+static const char *c_end_marker   = ";\n    /*LLDB_BODY_END*/\n";
+
 namespace {
 
 class AddMacroState
@@ -106,8 +111,6 @@ public:
         {
             case CURRENT_FILE_NOT_YET_PUSHED:
                 return true;
-            case CURRENT_FILE_POPPED:
-                return false;
             case CURRENT_FILE_PUSHED:
                 // If we are in file included in the current file,
                 // the entry should be added.
@@ -118,6 +121,8 @@ public:
                     return false;
                 else
                     return true;
+            default:
+                return false;
         }
     }
 
@@ -175,12 +180,28 @@ AddMacros(const DebugMacros *dm, CompileUnit *comp_unit, AddMacroState &state, S
     }
 }
 
-bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrapping_language, bool const_object, bool static_method, ExecutionContext &exe_ctx) const
+static void
+AddLocalVariableDecls(const lldb::VariableListSP &var_list_sp, StreamString &stream)
+{
+    for (size_t i = 0; i < var_list_sp->GetSize(); i++)
+    {
+        lldb::VariableSP var_sp = var_list_sp->GetVariableAtIndex(i);
+
+        ConstString var_name = var_sp->GetName();
+        if (!var_name || var_name == ConstString("this") || var_name == ConstString(".block_descriptor"))
+            continue;
+
+        stream.Printf("using $__lldb_local_vars::%s;\n", var_name.AsCString());
+    }
+}
+
+bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrapping_language, bool static_method, ExecutionContext &exe_ctx) const
 {
     const char *target_specific_defines = "typedef signed char BOOL;\n";
     std::string module_macros;
     
-    if (Target *target = exe_ctx.GetTargetPtr())
+    Target *target = exe_ctx.GetTargetPtr();
+    if (target)
     {
         if (target->GetArchitecture().GetMachine() == llvm::Triple::aarch64)
         {
@@ -239,6 +260,7 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
     }
 
     StreamString debug_macros_stream;
+    StreamString lldb_local_var_decls;
     if (StackFrame *frame = exe_ctx.GetFramePtr())
     {
         const SymbolContext &sc = frame->GetSymbolContext(
@@ -253,8 +275,18 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
                 AddMacros(dm, sc.comp_unit, state, debug_macros_stream);
             }
         }
+
+        ConstString object_name;
+        if (Language::LanguageIsCPlusPlus(frame->GetLanguage()))
+        {
+            if (target->GetInjectLocalVariables(&exe_ctx))
+            {
+                lldb::VariableListSP var_list_sp = frame->GetInScopeVariableList(false, true);
+                AddLocalVariableDecls(var_list_sp, lldb_local_var_decls);
+            }
+        }
     }
-    
+
     if (m_wrap)
     {
         switch (wrapping_language) 
@@ -276,6 +308,22 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
                            target_specific_defines,
                            m_prefix.c_str());
         
+        // First construct a tagged form of the user expression so we can find it later:
+        std::string tagged_body;
+        switch (wrapping_language)
+        {
+            default:
+                tagged_body = m_body;
+                break;
+            case lldb::eLanguageTypeC:
+            case lldb::eLanguageTypeC_plus_plus:
+            case lldb::eLanguageTypeObjC:
+                tagged_body.append(c_start_marker);
+                tagged_body.append(m_body);
+                tagged_body.append(c_end_marker);
+                break;
+            
+        }
         switch (wrapping_language) 
         {
         default:
@@ -284,20 +332,23 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
             wrap_stream.Printf("void                           \n"
                                "%s(void *$__lldb_arg)          \n"
                                "{                              \n"
-                               "    %s;                        \n" 
+                               "    %s;                        \n"
+                               "%s"
                                "}                              \n",
                                m_name.c_str(),
-                               m_body.c_str());
+                               lldb_local_var_decls.GetData(),
+                               tagged_body.c_str());
             break;
         case lldb::eLanguageTypeC_plus_plus:
             wrap_stream.Printf("void                                   \n"
-                               "$__lldb_class::%s(void *$__lldb_arg) %s\n"
+                               "$__lldb_class::%s(void *$__lldb_arg)   \n"
                                "{                                      \n"
-                               "    %s;                                \n" 
+                               "    %s;                                \n"
+                               "%s"
                                "}                                      \n",
                                m_name.c_str(),
-                               (const_object ? "const" : ""),
-                               m_body.c_str());
+                               lldb_local_var_decls.GetData(),
+                               tagged_body.c_str());
             break;
         case lldb::eLanguageTypeObjC:
             if (static_method)
@@ -308,12 +359,12 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
                                    "@implementation $__lldb_objc_class ($__lldb_category)   \n"
                                    "+(void)%s:(void *)$__lldb_arg                           \n"
                                    "{                                                       \n"
-                                   "    %s;                                                 \n"
+                                   "%s"
                                    "}                                                       \n"
                                    "@end                                                    \n",
                                    m_name.c_str(),
                                    m_name.c_str(),
-                                   m_body.c_str());
+                                   tagged_body.c_str());
             }
             else
             {
@@ -323,12 +374,12 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
                                    "@implementation $__lldb_objc_class ($__lldb_category)  \n"
                                    "-(void)%s:(void *)$__lldb_arg                          \n"
                                    "{                                                      \n"
-                                   "    %s;                                                \n"
+                                   "%s"
                                    "}                                                      \n"
                                    "@end                                                   \n",
                                    m_name.c_str(),
                                    m_name.c_str(),
-                                   m_body.c_str());
+                                   tagged_body.c_str());
             }
             break;
         }
@@ -339,6 +390,38 @@ bool ExpressionSourceCode::GetText (std::string &text, lldb::LanguageType wrappi
     {
         text.append(m_body);
     }
+
+    return true;
+}
+
+bool
+ExpressionSourceCode::GetOriginalBodyBounds(std::string transformed_text,
+                                            lldb::LanguageType wrapping_language,
+                                            size_t &start_loc,
+                                            size_t &end_loc)
+{
+    const char *start_marker;
+    const char *end_marker;
     
+    switch (wrapping_language)
+    {
+    default:
+        return false;
+    case lldb::eLanguageTypeC:
+    case lldb::eLanguageTypeC_plus_plus:
+    case lldb::eLanguageTypeObjC:
+        start_marker = c_start_marker;
+        end_marker = c_end_marker;
+        break;
+    }
+    
+    start_loc = transformed_text.find(start_marker);
+    if (start_loc == std::string::npos)
+        return false;
+    start_loc += strlen(start_marker);
+    end_loc  = transformed_text.find(end_marker);
+    if (end_loc == std::string::npos)
+        return false;
     return true;
 }
+
diff --git a/source/Expression/ExpressionVariable.cpp b/source/Expression/ExpressionVariable.cpp
index 8bef60fdf1d7b..5567ee286aa94 100644
--- a/source/Expression/ExpressionVariable.cpp
+++ b/source/Expression/ExpressionVariable.cpp
@@ -7,7 +7,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "lldb/Core/Log.h"
 #include "lldb/Expression/ExpressionVariable.h"
+#include "lldb/Expression/IRExecutionUnit.h"
 
 using namespace lldb_private;
 
@@ -34,3 +36,55 @@ ExpressionVariable::GetValueBytes()
 PersistentExpressionState::~PersistentExpressionState ()
 {
 }
+
+lldb::addr_t
+PersistentExpressionState::LookupSymbol (const ConstString &name)
+{
+    SymbolMap::iterator si = m_symbol_map.find(name.GetCString());
+    
+    if (si != m_symbol_map.end())
+        return si->second;
+    else
+        return LLDB_INVALID_ADDRESS;
+}
+
+
+void
+PersistentExpressionState::RegisterExecutionUnit (lldb::IRExecutionUnitSP &execution_unit_sp)
+{
+    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
+    
+    m_execution_units.insert(execution_unit_sp);
+    
+    if (log)
+        log->Printf ("Registering JITted Functions:\n");
+    
+    for (const IRExecutionUnit::JittedFunction &jitted_function : execution_unit_sp->GetJittedFunctions())
+    {
+        if (jitted_function.m_external &&
+            jitted_function.m_name != execution_unit_sp->GetFunctionName() &&
+            jitted_function.m_remote_addr != LLDB_INVALID_ADDRESS)
+        {
+            m_symbol_map[jitted_function.m_name.GetCString()] = jitted_function.m_remote_addr;
+            if (log)
+                log->Printf ("  Function: %s at 0x%" PRIx64 ".", jitted_function.m_name.GetCString(), jitted_function.m_remote_addr);
+        }
+    }
+    
+    if (log)
+        log->Printf ("Registering JIIted Symbols:\n");
+    
+    for (const IRExecutionUnit::JittedGlobalVariable &global_var : execution_unit_sp->GetJittedGlobalVariables())
+    {
+        if (global_var.m_remote_addr != LLDB_INVALID_ADDRESS)
+        {
+            // Demangle the name before inserting it, so that lookups by the ConstStr of the demangled name
+            // will find the mangled one (needed for looking up metadata pointers.)
+            Mangled mangler(global_var.m_name);
+            mangler.GetDemangledName(lldb::eLanguageTypeUnknown);
+            m_symbol_map[global_var.m_name.GetCString()] = global_var.m_remote_addr;
+            if (log)
+                log->Printf ("  Symbol: %s at 0x%" PRIx64 ".", global_var.m_name.GetCString(), global_var.m_remote_addr);
+        }
+    }
+}
diff --git a/source/Expression/FunctionCaller.cpp b/source/Expression/FunctionCaller.cpp
index ddc378dcb4161..3a4f1fe33add0 100644
--- a/source/Expression/FunctionCaller.cpp
+++ b/source/Expression/FunctionCaller.cpp
@@ -13,13 +13,14 @@
 // Other libraries and framework includes
 
 // Project includes
+#include "lldb/Expression/FunctionCaller.h"
 #include "lldb/Core/DataExtractor.h"
 #include "lldb/Core/Log.h"
 #include "lldb/Core/Module.h"
 #include "lldb/Core/State.h"
 #include "lldb/Core/ValueObject.h"
 #include "lldb/Core/ValueObjectList.h"
-#include "lldb/Expression/FunctionCaller.h"
+#include "lldb/Expression/DiagnosticManager.h"
 #include "lldb/Expression/IRExecutionUnit.h"
 #include "lldb/Interpreter/CommandReturnObject.h"
 #include "lldb/Symbol/Function.h"
@@ -76,11 +77,11 @@ FunctionCaller::~FunctionCaller()
         lldb::ModuleSP jit_module_sp (m_jit_module_wp.lock());
         if (jit_module_sp)
             process_sp->GetTarget().GetImages().Remove(jit_module_sp);
-    }    
+    }
 }
 
 bool
-FunctionCaller::WriteFunctionWrapper (ExecutionContext &exe_ctx, Stream &errors)
+FunctionCaller::WriteFunctionWrapper(ExecutionContext &exe_ctx, DiagnosticManager &diagnostic_manager)
 {
     Process *process = exe_ctx.GetProcessPtr();
 
@@ -133,27 +134,28 @@ FunctionCaller::WriteFunctionWrapper (ExecutionContext &exe_ctx, Stream &errors)
 }
 
 bool
-FunctionCaller::WriteFunctionArguments (ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, Stream &errors)
+FunctionCaller::WriteFunctionArguments(ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref,
+                                       DiagnosticManager &diagnostic_manager)
 {
-    return WriteFunctionArguments(exe_ctx, args_addr_ref, m_arg_values, errors);
+    return WriteFunctionArguments(exe_ctx, args_addr_ref, m_arg_values, diagnostic_manager);
 }
 
 // FIXME: Assure that the ValueList we were passed in is consistent with the one that defined this function.
 
 bool
-FunctionCaller::WriteFunctionArguments (ExecutionContext &exe_ctx, 
-                                       lldb::addr_t &args_addr_ref, 
-                                       ValueList &arg_values,
-                                       Stream &errors)
+FunctionCaller::WriteFunctionArguments(ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, ValueList &arg_values,
+                                       DiagnosticManager &diagnostic_manager)
 {
     // All the information to reconstruct the struct is provided by the
     // StructExtractor.
     if (!m_struct_valid)
     {
-        errors.Printf("Argument information was not correctly parsed, so the function cannot be called.");
+        diagnostic_manager.PutCString(
+            eDiagnosticSeverityError,
+            "Argument information was not correctly parsed, so the function cannot be called.");
         return false;
     }
-        
+
     Error error;
     lldb::ExpressionResults return_value = lldb::eExpressionSetupError;
 
@@ -191,14 +193,16 @@ FunctionCaller::WriteFunctionArguments (ExecutionContext &exe_ctx,
     // FIXME: We will need to extend this for Variadic functions.
 
     Error value_error;
-    
+
     size_t num_args = arg_values.GetSize();
     if (num_args != m_arg_values.GetSize())
     {
-        errors.Printf ("Wrong number of arguments - was: %" PRIu64 " should be: %" PRIu64 "", (uint64_t)num_args, (uint64_t)m_arg_values.GetSize());
+        diagnostic_manager.Printf(eDiagnosticSeverityError,
+                                  "Wrong number of arguments - was: %" PRIu64 " should be: %" PRIu64 "",
+                                  (uint64_t)num_args, (uint64_t)m_arg_values.GetSize());
         return false;
     }
-    
+
     for (size_t i = 0; i < num_args; i++)
     {
         // FIXME: We should sanity check sizes.
@@ -225,16 +229,17 @@ FunctionCaller::WriteFunctionArguments (ExecutionContext &exe_ctx,
 }
 
 bool
-FunctionCaller::InsertFunction (ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref, Stream &errors)
+FunctionCaller::InsertFunction(ExecutionContext &exe_ctx, lldb::addr_t &args_addr_ref,
+                               DiagnosticManager &diagnostic_manager)
 {
-    if (CompileFunction(errors) != 0)
+    if (CompileFunction(exe_ctx.GetThreadSP(), diagnostic_manager) != 0)
         return false;
-    if (!WriteFunctionWrapper(exe_ctx, errors))
+    if (!WriteFunctionWrapper(exe_ctx, diagnostic_manager))
         return false;
-    if (!WriteFunctionArguments(exe_ctx, args_addr_ref, errors))
+    if (!WriteFunctionArguments(exe_ctx, args_addr_ref, diagnostic_manager))
         return false;
 
-    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP));
+    Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
     if (log)
         log->Printf ("Call Address: 0x%" PRIx64 " Struct Address: 0x%" PRIx64 ".\n", m_jit_start_addr, args_addr_ref);
         
@@ -242,13 +247,12 @@ FunctionCaller::InsertFunction (ExecutionContext &exe_ctx, lldb::addr_t &args_ad
 }
 
 lldb::ThreadPlanSP
-FunctionCaller::GetThreadPlanToCallFunction (ExecutionContext &exe_ctx, 
-                                            lldb::addr_t args_addr,
+FunctionCaller::GetThreadPlanToCallFunction(ExecutionContext &exe_ctx, lldb::addr_t args_addr,
                                             const EvaluateExpressionOptions &options,
-                                            Stream &errors)
+                                            DiagnosticManager &diagnostic_manager)
 {
-    Log *log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP));
-    
+    Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP));
+
     if (log)
         log->Printf("-- [FunctionCaller::GetThreadPlanToCallFunction] Creating thread plan to call function \"%s\" --", m_name.c_str());
     
@@ -256,7 +260,7 @@ FunctionCaller::GetThreadPlanToCallFunction (ExecutionContext &exe_ctx,
     Thread *thread = exe_ctx.GetThreadPtr();
     if (thread == NULL)
     {
-        errors.Printf("Can't call a function without a valid thread.");
+        diagnostic_manager.PutCString(eDiagnosticSeverityError, "Can't call a function without a valid thread.");
         return NULL;
     }
 
@@ -322,15 +326,12 @@ FunctionCaller::DeallocateFunctionResults (ExecutionContext &exe_ctx, lldb::addr
 }
 
 lldb::ExpressionResults
-FunctionCaller::ExecuteFunction(
-        ExecutionContext &exe_ctx, 
-        lldb::addr_t *args_addr_ptr,
-        const EvaluateExpressionOptions &options,
-        Stream &errors, 
-        Value &results)
+FunctionCaller::ExecuteFunction(ExecutionContext &exe_ctx, lldb::addr_t *args_addr_ptr,
+                                const EvaluateExpressionOptions &options, DiagnosticManager &diagnostic_manager,
+                                Value &results)
 {
     lldb::ExpressionResults return_value = lldb::eExpressionSetupError;
-    
+
     // FunctionCaller::ExecuteFunction execution is always just to get the result.  Do make sure we ignore
     // breakpoints, unwind on error, and don't try to debug it.
     EvaluateExpressionOptions real_options = options;
@@ -345,12 +346,12 @@ FunctionCaller::ExecuteFunction(
     else
         args_addr = LLDB_INVALID_ADDRESS;
         
-    if (CompileFunction(errors) != 0)
+    if (CompileFunction(exe_ctx.GetThreadSP(), diagnostic_manager) != 0)
         return lldb::eExpressionSetupError;
-    
+
     if (args_addr == LLDB_INVALID_ADDRESS)
     {
-        if (!InsertFunction(exe_ctx, args_addr, errors))
+        if (!InsertFunction(exe_ctx, args_addr, diagnostic_manager))
             return lldb::eExpressionSetupError;
     }
 
@@ -358,24 +359,18 @@ FunctionCaller::ExecuteFunction(
 
     if (log)
         log->Printf("== [FunctionCaller::ExecuteFunction] Executing function \"%s\" ==", m_name.c_str());
-    
-    lldb::ThreadPlanSP call_plan_sp = GetThreadPlanToCallFunction (exe_ctx,
-                                                                   args_addr,
-                                                                   real_options,
-                                                                   errors);
+
+    lldb::ThreadPlanSP call_plan_sp = GetThreadPlanToCallFunction(exe_ctx, args_addr, real_options, diagnostic_manager);
     if (!call_plan_sp)
         return lldb::eExpressionSetupError;
-        
+
     // We need to make sure we record the fact that we are running an expression here
     // otherwise this fact will fail to be recorded when fetching an Objective-C object description
     if (exe_ctx.GetProcessPtr())
         exe_ctx.GetProcessPtr()->SetRunningUserExpression(true);
-    
-    return_value = exe_ctx.GetProcessRef().RunThreadPlan (exe_ctx,
-                                                          call_plan_sp,
-                                                          real_options,
-                                                          errors);
-    
+
+    return_value = exe_ctx.GetProcessRef().RunThreadPlan(exe_ctx, call_plan_sp, real_options, diagnostic_manager);
+
     if (log)
     {
         if (return_value != lldb::eExpressionCompleted)
diff --git a/source/Expression/IRDynamicChecks.cpp b/source/Expression/IRDynamicChecks.cpp
index 64fdb08157aa7..62bcfe0d14b83 100644
--- a/source/Expression/IRDynamicChecks.cpp
+++ b/source/Expression/IRDynamicChecks.cpp
@@ -50,8 +50,7 @@ DynamicCheckerFunctions::DynamicCheckerFunctions() = default;
 DynamicCheckerFunctions::~DynamicCheckerFunctions() = default;
 
 bool
-DynamicCheckerFunctions::Install(Stream &error_stream,
-                                 ExecutionContext &exe_ctx)
+DynamicCheckerFunctions::Install(DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx)
 {
     Error error;
     m_valid_pointer_check.reset(exe_ctx.GetTargetRef().GetUtilityFunctionForLanguage(g_valid_pointer_check_text,
@@ -60,8 +59,8 @@ DynamicCheckerFunctions::Install(Stream &error_stream,
                                                                                      error));
     if (error.Fail())
         return false;
-        
-    if (!m_valid_pointer_check->Install(error_stream, exe_ctx))
+
+    if (!m_valid_pointer_check->Install(diagnostic_manager, exe_ctx))
         return false;
 
     Process *process = exe_ctx.GetProcessPtr();
@@ -74,7 +73,7 @@ DynamicCheckerFunctions::Install(Stream &error_stream,
         {
             m_objc_object_check.reset(objc_language_runtime->CreateObjectChecker(VALID_OBJC_OBJECT_CHECK_NAME));
 
-            if (!m_objc_object_check->Install(error_stream, exe_ctx))
+            if (!m_objc_object_check->Install(diagnostic_manager, exe_ctx))
                 return false;
         }
     }
@@ -506,6 +505,32 @@ protected:
 
         return true;
     }
+    
+    static llvm::Function *GetFunction(llvm::Value *value)
+    {
+        if (llvm::Function *function = llvm::dyn_cast<llvm::Function>(value))
+        {
+            return function;
+        }
+        
+        if (llvm::ConstantExpr *const_expr = llvm::dyn_cast<llvm::ConstantExpr>(value))
+        {
+            switch (const_expr->getOpcode())
+            {
+            default:
+                return nullptr;
+            case llvm::Instruction::BitCast:
+                return GetFunction(const_expr->getOperand(0));
+            }
+        }
+        
+        return nullptr;
+    }
+    
+    static llvm::Function *GetCalledFunction(llvm::CallInst *inst)
+    {
+        return GetFunction(inst->getCalledValue());
+    }
 
     bool InspectInstruction(llvm::Instruction &i) override
     {
@@ -515,35 +540,12 @@ protected:
 
         if (call_inst)
         {
-            // This metadata is set by IRForTarget::MaybeHandleCall().
-
-            MDNode *metadata = call_inst->getMetadata("lldb.call.realName");
-
-            if (!metadata)
+            const llvm::Function *called_function = GetCalledFunction(call_inst);
+            
+            if (!called_function)
                 return true;
-
-            if (metadata->getNumOperands() != 1)
-            {
-                if (log)
-                    log->Printf("Function call metadata has %d operands for [%p] %s",
-                                metadata->getNumOperands(),
-                                static_cast<void*>(call_inst),
-                                PrintValue(call_inst).c_str());
-                return false;
-            }
-
-            MDString *real_name = dyn_cast<MDString>(metadata->getOperand(0));
-
-            if (!real_name)
-            {
-                if (log)
-                    log->Printf("Function call metadata is not an MDString for [%p] %s",
-                                static_cast<void*>(call_inst),
-                                PrintValue(call_inst).c_str());
-                return false;
-            }
-
-            std::string name_str = real_name->getString();
+            
+            std::string name_str = called_function->getName().str();
             const char* name_cstr = name_str.c_str();
 
             if (log)
diff --git a/source/Expression/IRExecutionUnit.cpp b/source/Expression/IRExecutionUnit.cpp
index 3f19c508c9267..103d76328c3a8 100644
--- a/source/Expression/IRExecutionUnit.cpp
+++ b/source/Expression/IRExecutionUnit.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/ExecutionEngine/ExecutionEngine.h"
+#include "llvm/IR/Constants.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
 #include "llvm/Support/SourceMgr.h"
@@ -20,11 +21,17 @@
 #include "lldb/Core/Log.h"
 #include "lldb/Core/Module.h"
 #include "lldb/Core/Section.h"
+#include "lldb/Symbol/CompileUnit.h"
 #include "lldb/Symbol/SymbolContext.h"
+#include "lldb/Symbol/SymbolVendor.h"
+#include "lldb/Symbol/SymbolFile.h"
 #include "lldb/Expression/IRExecutionUnit.h"
 #include "lldb/Target/ExecutionContext.h"
 #include "lldb/Target/Target.h"
 #include "lldb/Target/ObjCLanguageRuntime.h"
+#include "lldb/Utility/LLDBAssert.h"
+
+#include "lldb/../../source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.h"
 
 using namespace lldb_private;
 
@@ -32,6 +39,7 @@ IRExecutionUnit::IRExecutionUnit (std::unique_ptr<llvm::LLVMContext> &context_ap
                                   std::unique_ptr<llvm::Module> &module_ap,
                                   ConstString &name,
                                   const lldb::TargetSP &target_sp,
+                                  const SymbolContext &sym_ctx,
                                   std::vector<std::string> &cpu_features) :
     IRMemoryMap(target_sp),
     m_context_ap(context_ap.release()),
@@ -39,9 +47,11 @@ IRExecutionUnit::IRExecutionUnit (std::unique_ptr<llvm::LLVMContext> &context_ap
     m_module(m_module_ap.get()),
     m_cpu_features(cpu_features),
     m_name(name),
+    m_sym_ctx(sym_ctx),
     m_did_jit(false),
     m_function_load_addr(LLDB_INVALID_ADDRESS),
-    m_function_end_load_addr(LLDB_INVALID_ADDRESS)
+    m_function_end_load_addr(LLDB_INVALID_ADDRESS),
+    m_reported_allocations(false)
 {
 }
 
@@ -115,7 +125,7 @@ IRExecutionUnit::DisassembleFunction (Stream &stream,
 
     for (JittedFunction &function : m_jitted_functions)
     {
-        if (strstr(function.m_name.c_str(), m_name.AsCString()))
+        if (function.m_name == m_name)
         {
             func_local_addr = function.m_local_addr;
             func_remote_addr = function.m_remote_addr;
@@ -206,10 +216,6 @@ IRExecutionUnit::DisassembleFunction (Stream &stream,
 
     InstructionList &instruction_list = disassembler_sp->GetInstructionList();
     instruction_list.Dump(&stream, true, true, &exe_ctx);
-    
-    // FIXME: The DisassemblerLLVMC has a reference cycle and won't go away if it has any active instructions.
-    // I'll fix that but for now, just clear the list and it will go away nicely.
-    disassembler_sp->GetInstructionList().Clear();
     return ret;
 }
 
@@ -237,7 +243,7 @@ IRExecutionUnit::GetRunnableInfo(Error &error,
 {
     lldb::ProcessSP process_sp(GetProcessWP().lock());
 
-    static Mutex s_runnable_info_mutex(Mutex::Type::eMutexTypeRecursive);
+    static std::recursive_mutex s_runnable_info_mutex;
 
     func_addr = LLDB_INVALID_ADDRESS;
     func_end = LLDB_INVALID_ADDRESS;
@@ -257,7 +263,7 @@ IRExecutionUnit::GetRunnableInfo(Error &error,
         return;
     };
 
-    Mutex::Locker runnable_info_mutex_locker(s_runnable_info_mutex);
+    std::lock_guard<std::recursive_mutex> guard(s_runnable_info_mutex);
 
     m_did_jit = true;
 
@@ -278,22 +284,21 @@ IRExecutionUnit::GetRunnableInfo(Error &error,
     }
 
     llvm::Triple triple(m_module->getTargetTriple());
-    llvm::Function *function = m_module->getFunction (m_name.AsCString());
     llvm::Reloc::Model relocModel;
     llvm::CodeModel::Model codeModel;
 
     if (triple.isOSBinFormatELF())
     {
         relocModel = llvm::Reloc::Static;
-        // This will be small for 32-bit and large for 64-bit.
-        codeModel = llvm::CodeModel::JITDefault;
     }
     else
     {
         relocModel = llvm::Reloc::PIC_;
-        codeModel = llvm::CodeModel::Small;
     }
 
+    // This will be small for 32-bit and large for 64-bit.
+    codeModel = llvm::CodeModel::JITDefault;
+
     m_module_ap->getContext().setInlineAsmDiagnosticHandler(ReportInlineAsmError, &error);
 
     llvm::EngineBuilder builder(std::move(m_module_ap));
@@ -319,6 +324,8 @@ IRExecutionUnit::GetRunnableInfo(Error &error,
 
     m_execution_engine_ap.reset(builder.create(target_machine));
 
+    m_strip_underscore = (m_execution_engine_ap->getDataLayout().getGlobalPrefix() == '_');
+
     if (!m_execution_engine_ap.get())
     {
         error.SetErrorToGenericError();
@@ -331,44 +338,79 @@ IRExecutionUnit::GetRunnableInfo(Error &error,
 
     m_execution_engine_ap->DisableLazyCompilation();
 
-    // We don't actually need the function pointer here, this just forces it to get resolved.
-
-    void *fun_ptr = m_execution_engine_ap->getPointerToFunction(function);
-
-    if (!error.Success())
+    for (llvm::Function &function : *m_module)
     {
-        // We got an error through our callback!
-        return;
+        if (function.isDeclaration() || function.hasPrivateLinkage())
+            continue;
+        
+        const bool external = function.hasExternalLinkage() || function.hasLinkOnceODRLinkage();
+        
+        void *fun_ptr = m_execution_engine_ap->getPointerToFunction(&function);
+        
+        if (!error.Success())
+        {
+            // We got an error through our callback!
+            return;
+        }
+        
+        if (!fun_ptr)
+        {
+            error.SetErrorToGenericError();
+            error.SetErrorStringWithFormat("'%s' was in the JITted module but wasn't lowered", function.getName().str().c_str());
+            return;
+        }
+        m_jitted_functions.push_back (JittedFunction(function.getName().str().c_str(), external, (lldb::addr_t)fun_ptr));
     }
 
-    if (!function)
+    CommitAllocations(process_sp);
+    ReportAllocations(*m_execution_engine_ap);
+    
+    // We have to do this after calling ReportAllocations because for the MCJIT, getGlobalValueAddress
+    // will cause the JIT to perform all relocations.  That can only be done once, and has to happen
+    // after we do the remapping from local -> remote.
+    // That means we don't know the local address of the Variables, but we don't need that for anything,
+    // so that's okay.
+    
+    std::function<void (llvm::GlobalValue &)> RegisterOneValue = [this] (llvm::GlobalValue &val) {
+        if (val.hasExternalLinkage() && !val.isDeclaration())
+        {
+            uint64_t var_ptr_addr = m_execution_engine_ap->getGlobalValueAddress(val.getName().str());
+            
+            lldb::addr_t remote_addr = GetRemoteAddressForLocal(var_ptr_addr);
+            
+            // This is a really unfortunae API that sometimes returns local addresses and sometimes returns remote addresses, based on whether
+            // the variable was relocated during ReportAllocations or not.
+            
+            if (remote_addr == LLDB_INVALID_ADDRESS)
+            {
+                remote_addr = var_ptr_addr;
+            }
+                
+            if (var_ptr_addr != 0)
+                m_jitted_global_variables.push_back (JittedGlobalVariable (val.getName().str().c_str(), LLDB_INVALID_ADDRESS, remote_addr));
+        }
+    };
+    
+    for (llvm::GlobalVariable &global_var : m_module->getGlobalList())
     {
-        error.SetErrorToGenericError();
-        error.SetErrorStringWithFormat("Couldn't find '%s' in the JITted module", m_name.AsCString());
-        return;
+        RegisterOneValue(global_var);
     }
-
-    if (!fun_ptr)
+    
+    for (llvm::GlobalAlias &global_alias : m_module->getAliasList())
     {
-        error.SetErrorToGenericError();
-        error.SetErrorStringWithFormat("'%s' was in the JITted module but wasn't lowered", m_name.AsCString());
-        return;
+        RegisterOneValue(global_alias);
     }
 
-    m_jitted_functions.push_back (JittedFunction(m_name.AsCString(), (lldb::addr_t)fun_ptr));
-
-    CommitAllocations(process_sp);
-    ReportAllocations(*m_execution_engine_ap);
     WriteData(process_sp);
 
     if (m_failed_lookups.size())
     {
         StreamString ss;
-        
+
         ss.PutCString("Couldn't lookup symbols:\n");
-        
+
         bool emitNewLine = false;
-        
+
         for (const ConstString &failed_lookup : m_failed_lookups)
         {
             if (emitNewLine)
@@ -377,14 +419,14 @@ IRExecutionUnit::GetRunnableInfo(Error &error,
             ss.PutCString("  ");
             ss.PutCString(Mangled(failed_lookup).GetDemangledName(lldb::eLanguageTypeObjC_plus_plus).AsCString());
         }
-        
+
         m_failed_lookups.clear();
-        
+
         error.SetErrorString(ss.GetData());
-        
+
         return;
     }
-    
+
     m_function_load_addr = LLDB_INVALID_ADDRESS;
     m_function_end_load_addr = LLDB_INVALID_ADDRESS;
 
@@ -392,7 +434,7 @@ IRExecutionUnit::GetRunnableInfo(Error &error,
     {
         jitted_function.m_remote_addr = GetRemoteAddressForLocal (jitted_function.m_local_addr);
 
-        if (!jitted_function.m_name.compare(m_name.AsCString()))
+        if (!m_name.IsEmpty() && jitted_function.m_name == m_name)
         {
             AddrRange func_range = GetRemoteRangeForLocal(jitted_function.m_local_addr);
             m_function_end_load_addr = func_range.first + func_range.second;
@@ -437,7 +479,7 @@ IRExecutionUnit::GetRunnableInfo(Error &error,
             else
             {
                 record.dump(log);
-                
+
                 DataExtractor my_extractor ((const void*)record.m_host_address, record.m_size, lldb::eByteOrderBig, 8);
                 my_extractor.PutToLog(log, 0, record.m_size, record.m_host_address, 16, DataExtractor::TypeUInt8);
             }
@@ -603,6 +645,14 @@ IRExecutionUnit::MemoryManager::allocateCodeSection(uintptr_t Size,
         log->Printf("IRExecutionUnit::allocateCodeSection(Size=0x%" PRIx64 ", Alignment=%u, SectionID=%u) = %p",
                     (uint64_t)Size, Alignment, SectionID, (void *)return_value);
     }
+    
+    if (m_parent.m_reported_allocations)
+    {
+        Error err;
+        lldb::ProcessSP process_sp = m_parent.GetBestExecutionContextScope()->CalculateProcess();
+        
+        m_parent.CommitOneAllocation(process_sp, err, m_parent.m_records.back());
+    }
 
     return return_value;
 }
@@ -633,105 +683,449 @@ IRExecutionUnit::MemoryManager::allocateDataSection(uintptr_t Size,
         log->Printf("IRExecutionUnit::allocateDataSection(Size=0x%" PRIx64 ", Alignment=%u, SectionID=%u) = %p",
                     (uint64_t)Size, Alignment, SectionID, (void *)return_value);
     }
+    
+    if (m_parent.m_reported_allocations)
+    {
+        Error err;
+        lldb::ProcessSP process_sp = m_parent.GetBestExecutionContextScope()->CalculateProcess();
+        
+        m_parent.CommitOneAllocation(process_sp, err, m_parent.m_records.back());
+    }
 
     return return_value;
 }
 
-uint64_t
-IRExecutionUnit::MemoryManager::getSymbolAddress(const std::string &Name)
+static ConstString
+FindBestAlternateMangledName(const ConstString &demangled,
+                             const lldb::LanguageType &lang_type,
+                             const SymbolContext &sym_ctx)
 {
-    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
-    
-    SymbolContextList sc_list;
-    
-    ExecutionContextScope *exe_scope = m_parent.GetBestExecutionContextScope();
-    
-    lldb::TargetSP target_sp = exe_scope->CalculateTarget();
-    
-    const char *name = Name.c_str();
-    
-    ConstString bare_name_cs(name);
-    ConstString name_cs;
-    
-    if (name[0] == '_')
-        name_cs = ConstString(name + 1);
-    
-    if (!target_sp)
+    CPlusPlusLanguage::MethodName cpp_name(demangled);
+    std::string scope_qualified_name = cpp_name.GetScopeQualifiedName();
+
+    if (!scope_qualified_name.size())
+        return ConstString();
+
+    if (!sym_ctx.module_sp)
+        return ConstString();
+
+    SymbolVendor *sym_vendor = sym_ctx.module_sp->GetSymbolVendor();
+    if (!sym_vendor)
+        return ConstString();
+
+    lldb_private::SymbolFile *sym_file = sym_vendor->GetSymbolFile();
+    if (!sym_file)
+        return ConstString();
+
+    std::vector<ConstString> alternates;
+    sym_file->GetMangledNamesForFunction(scope_qualified_name, alternates);
+
+    std::vector<ConstString> param_and_qual_matches;
+    std::vector<ConstString> param_matches;
+    for (size_t i = 0; i < alternates.size(); i++)
     {
-        if (log)
-            log->Printf("IRExecutionUnit::getSymbolAddress(Name=\"%s\") = <no target>",
-                        Name.c_str());
-        
-        m_parent.ReportSymbolLookupError(name_cs);
-        
-        return 0xbad0bad0;
+        ConstString alternate_mangled_name = alternates[i];
+        Mangled mangled(alternate_mangled_name, true);
+        ConstString demangled = mangled.GetDemangledName(lang_type);
+
+        CPlusPlusLanguage::MethodName alternate_cpp_name(demangled);
+        if (!cpp_name.IsValid())
+            continue;
+
+        if (alternate_cpp_name.GetArguments() == cpp_name.GetArguments())
+        {
+            if (alternate_cpp_name.GetQualifiers() == cpp_name.GetQualifiers())
+                param_and_qual_matches.push_back(alternate_mangled_name);
+            else
+                param_matches.push_back(alternate_mangled_name);
+        }
     }
-    
-    uint32_t num_matches = 0;
-    lldb::ProcessSP process_sp = exe_scope->CalculateProcess();
-    
-    if (!name_cs.IsEmpty())
+
+    if (param_and_qual_matches.size())
+        return param_and_qual_matches[0]; // It is assumed that there will be only one!
+    else if (param_matches.size())
+        return param_matches[0]; // Return one of them as a best match
+    else
+        return ConstString();
+}
+
+struct IRExecutionUnit::SearchSpec
+{
+    ConstString name;
+    uint32_t    mask;
+
+    SearchSpec(ConstString n, uint32_t m = lldb::eFunctionNameTypeFull) :
+        name(n),
+        mask(m)
     {
-        target_sp->GetImages().FindSymbolsWithNameAndType(name_cs, lldb::eSymbolTypeAny, sc_list);
-        num_matches = sc_list.GetSize();
     }
-    
-    if (!num_matches)
+};
+
+void
+IRExecutionUnit::CollectCandidateCNames(std::vector<IRExecutionUnit::SearchSpec> &C_specs, const ConstString &name)
+{
+    if (m_strip_underscore && name.AsCString()[0] == '_')
+        C_specs.insert(C_specs.begin(), ConstString(&name.AsCString()[1]));
+    C_specs.push_back(SearchSpec(name));
+}
+
+void
+IRExecutionUnit::CollectCandidateCPlusPlusNames(std::vector<IRExecutionUnit::SearchSpec> &CPP_specs, const std::vector<SearchSpec> &C_specs, const SymbolContext &sc)
+{
+    for (const SearchSpec &C_spec : C_specs)
     {
-        target_sp->GetImages().FindSymbolsWithNameAndType(bare_name_cs, lldb::eSymbolTypeAny, sc_list);
-        num_matches = sc_list.GetSize();
+        const ConstString &name = C_spec.name;
+
+        if (CPlusPlusLanguage::IsCPPMangledName(name.GetCString()))
+        {
+            Mangled mangled(name, true);
+            ConstString demangled = mangled.GetDemangledName(lldb::eLanguageTypeC_plus_plus);
+
+            if (demangled)
+            {
+                ConstString best_alternate_mangled_name = FindBestAlternateMangledName(demangled, lldb::eLanguageTypeC_plus_plus, sc);
+
+                if (best_alternate_mangled_name)
+                {
+                    CPP_specs.push_back(best_alternate_mangled_name);
+                }
+
+                CPP_specs.push_back(SearchSpec(demangled, lldb::eFunctionNameTypeFull));
+            }
+        }
+
+        // Maybe we're looking for a const symbol but the debug info told us it was const...
+        if (!strncmp(name.GetCString(), "_ZN", 3) &&
+            strncmp(name.GetCString(), "_ZNK", 4))
+        {
+            std::string fixed_scratch("_ZNK");
+            fixed_scratch.append(name.GetCString() + 3);
+            CPP_specs.push_back(ConstString(fixed_scratch.c_str()));
+        }
+
+        // Maybe we're looking for a static symbol but we thought it was global...
+        if (!strncmp(name.GetCString(), "_Z", 2) &&
+            strncmp(name.GetCString(), "_ZL", 3))
+        {
+            std::string fixed_scratch("_ZL");
+            fixed_scratch.append(name.GetCString() + 2);
+            CPP_specs.push_back(ConstString(fixed_scratch.c_str()));
+        }
+
     }
-        
-    lldb::addr_t symbol_load_addr = LLDB_INVALID_ADDRESS;
+}
+
+void
+IRExecutionUnit::CollectFallbackNames(std::vector<SearchSpec> &fallback_specs,
+                                      const std::vector<SearchSpec> &C_specs)
+{
+    // As a last-ditch fallback, try the base name for C++ names.  It's terrible,
+    // but the DWARF doesn't always encode "extern C" correctly.
     
-    for (uint32_t i=0; i<num_matches && (symbol_load_addr == 0 || symbol_load_addr == LLDB_INVALID_ADDRESS); i++)
+    for (const SearchSpec &C_spec : C_specs)
     {
-        SymbolContext sym_ctx;
-        sc_list.GetContextAtIndex(i, sym_ctx);
+        const ConstString &name = C_spec.name;
         
-        symbol_load_addr = sym_ctx.symbol->ResolveCallableAddress(*target_sp);
+        if (CPlusPlusLanguage::IsCPPMangledName(name.GetCString()))
+        {
+            Mangled mangled_name(name);
+            ConstString demangled_name = mangled_name.GetDemangledName(lldb::eLanguageTypeC_plus_plus);
+            if (!demangled_name.IsEmpty())
+            {
+                const char *demangled_cstr = demangled_name.AsCString();
+                const char *lparen_loc = strchr(demangled_cstr, '(');
+                if (lparen_loc)
+                {
+                    llvm::StringRef base_name(demangled_cstr, lparen_loc-demangled_cstr);
+                    fallback_specs.push_back(ConstString(base_name));
+                }
+            }
+        }
+    }
+}
+
+
+lldb::addr_t
+IRExecutionUnit::FindInSymbols(const std::vector<IRExecutionUnit::SearchSpec> &specs, const lldb_private::SymbolContext &sc)
+{
+    Target *target = sc.target_sp.get();
 
-        if (symbol_load_addr == LLDB_INVALID_ADDRESS)
-            symbol_load_addr = sym_ctx.symbol->GetAddress().GetLoadAddress(target_sp.get());
+    if (!target)
+    {
+        // we shouldn't be doing any symbol lookup at all without a target
+        return LLDB_INVALID_ADDRESS;
     }
+
+    for (const SearchSpec &spec : specs)
+    {
+        SymbolContextList sc_list;
+
+        lldb::addr_t best_internal_load_address = LLDB_INVALID_ADDRESS;
+
+        std::function<bool (lldb::addr_t &, SymbolContextList &, const lldb_private::SymbolContext &)> get_external_load_address =
+            [&best_internal_load_address, target](lldb::addr_t &load_address,
+                                                  SymbolContextList &sc_list,
+                                                  const lldb_private::SymbolContext &sc) -> lldb::addr_t
+        {
+            load_address = LLDB_INVALID_ADDRESS;
+
+            for (size_t si = 0, se = sc_list.GetSize(); si < se; ++si)
+            {
+                SymbolContext candidate_sc;
+
+                sc_list.GetContextAtIndex(si, candidate_sc);
+
+                const bool is_external = (candidate_sc.function) ||
+                                         (candidate_sc.symbol && candidate_sc.symbol->IsExternal());
+                if (candidate_sc.symbol)
+                {
+                    load_address = candidate_sc.symbol->ResolveCallableAddress(*target);
+
+                    if (load_address == LLDB_INVALID_ADDRESS)
+                    {
+                        if (target->GetProcessSP())
+                            load_address = candidate_sc.symbol->GetAddress().GetLoadAddress(target);
+                        else
+                            load_address = candidate_sc.symbol->GetAddress().GetFileAddress();
+                    }
+                }
+
+                if (load_address == LLDB_INVALID_ADDRESS && candidate_sc.function)
+                {
+                        if (target->GetProcessSP())
+                            load_address = candidate_sc.function->GetAddressRange().GetBaseAddress().GetLoadAddress(target);
+                        else
+                            load_address = candidate_sc.function->GetAddressRange().GetBaseAddress().GetFileAddress();
+                }
+
+                if (load_address != LLDB_INVALID_ADDRESS)
+                {
+                    if (is_external)
+                    {
+                        return true;
+                    }
+                    else if (best_internal_load_address == LLDB_INVALID_ADDRESS)
+                    {
+                        best_internal_load_address = load_address;
+                        load_address = LLDB_INVALID_ADDRESS;
+                    }
+                }
+            }
+
+            return false;
+        };
+
+        if (sc.module_sp)
+        {
+            sc.module_sp->FindFunctions(spec.name,
+                                        NULL,
+                                        spec.mask,
+                                        true,  // include_symbols
+                                        false, // include_inlines
+                                        true,  // append
+                                        sc_list);
+        }
+
+        lldb::addr_t load_address = LLDB_INVALID_ADDRESS;
+
+        if (get_external_load_address(load_address, sc_list, sc))
+        {
+            return load_address;
+        }
+        else
+        {
+            sc_list.Clear();
+        }
+
+        if (sc_list.GetSize() == 0 && sc.target_sp)
+        {
+            sc.target_sp->GetImages().FindFunctions(spec.name,
+                                                    spec.mask,
+                                                    true,  // include_symbols
+                                                    false, // include_inlines
+                                                    true,  // append
+                                                    sc_list);
+        }
+
+        if (get_external_load_address(load_address, sc_list, sc))
+        {
+            return load_address;
+        }
+        else
+        {
+            sc_list.Clear();
+        }
+
+        if (sc_list.GetSize() == 0 && sc.target_sp)
+        {
+            sc.target_sp->GetImages().FindSymbolsWithNameAndType(spec.name, lldb::eSymbolTypeAny, sc_list);
+        }
+
+        if (get_external_load_address(load_address, sc_list, sc))
+        {
+            return load_address;
+        }
+        // if there are any searches we try after this, add an sc_list.Clear() in an "else" clause here
+
+        if (best_internal_load_address != LLDB_INVALID_ADDRESS)
+        {
+            return best_internal_load_address;
+        }
+    }
+
+    return LLDB_INVALID_ADDRESS;
+}
+
+lldb::addr_t
+IRExecutionUnit::FindInRuntimes(const std::vector<SearchSpec> &specs, const lldb_private::SymbolContext &sc)
+{
+    lldb::TargetSP target_sp = sc.target_sp;
+
+    if (!target_sp)
+    {
+        return LLDB_INVALID_ADDRESS;
+    }
+
+    lldb::ProcessSP process_sp = sc.target_sp->GetProcessSP();
+
+    if (!process_sp)
+    {
+        return LLDB_INVALID_ADDRESS;
+    }
+
+    ObjCLanguageRuntime *runtime = process_sp->GetObjCLanguageRuntime();
+
+    if (runtime)
+    {
+        for (const SearchSpec &spec : specs)
+        {
+            lldb::addr_t symbol_load_addr = runtime->LookupRuntimeSymbol(spec.name);
+
+            if (symbol_load_addr != LLDB_INVALID_ADDRESS)
+                return symbol_load_addr;
+        }
+    }
+
+    return LLDB_INVALID_ADDRESS;
+}
+
+lldb::addr_t
+IRExecutionUnit::FindInUserDefinedSymbols(const std::vector<SearchSpec> &specs, const lldb_private::SymbolContext &sc)
+{
+    lldb::TargetSP target_sp = sc.target_sp;
     
-    if (symbol_load_addr == LLDB_INVALID_ADDRESS && process_sp && name_cs)
+    for (const SearchSpec &spec : specs)
     {
-        // Try the Objective-C language runtime.
-        
-        ObjCLanguageRuntime *runtime = process_sp->GetObjCLanguageRuntime();
+        lldb::addr_t symbol_load_addr = target_sp->GetPersistentSymbol(spec.name);
         
-        if (runtime)
-            symbol_load_addr = runtime->LookupRuntimeSymbol(name_cs);
+        if (symbol_load_addr != LLDB_INVALID_ADDRESS)
+            return symbol_load_addr;
     }
     
-    if (symbol_load_addr == LLDB_INVALID_ADDRESS)
+    return LLDB_INVALID_ADDRESS;
+}
+
+lldb::addr_t
+IRExecutionUnit::FindSymbol(const lldb_private::ConstString &name)
+{
+    std::vector<SearchSpec> candidate_C_names;
+    std::vector<SearchSpec> candidate_CPlusPlus_names;
+
+    CollectCandidateCNames(candidate_C_names, name);
+
+    lldb::addr_t ret = FindInSymbols(candidate_C_names, m_sym_ctx);
+    if (ret == LLDB_INVALID_ADDRESS)
+        ret = FindInRuntimes(candidate_C_names, m_sym_ctx);
+
+    if (ret == LLDB_INVALID_ADDRESS)
+        ret = FindInUserDefinedSymbols(candidate_C_names, m_sym_ctx);
+
+    if (ret == LLDB_INVALID_ADDRESS)
+    {
+        CollectCandidateCPlusPlusNames(candidate_CPlusPlus_names, candidate_C_names, m_sym_ctx);
+        ret = FindInSymbols(candidate_CPlusPlus_names, m_sym_ctx);
+    }
+    
+    if (ret == LLDB_INVALID_ADDRESS)
+    {
+        std::vector<SearchSpec> candidate_fallback_names;
+
+        CollectFallbackNames(candidate_fallback_names, candidate_C_names);
+        ret = FindInSymbols(candidate_fallback_names, m_sym_ctx);
+    }
+
+    return ret;
+}
+
+void
+IRExecutionUnit::GetStaticInitializers(std::vector <lldb::addr_t> &static_initializers)
+{
+    if (llvm::GlobalVariable *global_ctors = m_module->getNamedGlobal("llvm.global_ctors"))
+    {
+        if (llvm::ConstantArray *ctor_array = llvm::dyn_cast<llvm::ConstantArray>(global_ctors->getInitializer()))
+        {
+            for (llvm::Use &ctor_use : ctor_array->operands())
+            {
+                if (llvm::ConstantStruct *ctor_struct = llvm::dyn_cast<llvm::ConstantStruct>(ctor_use))
+                {
+                    lldbassert(ctor_struct->getNumOperands() == 3); // this is standardized
+                    if (llvm::Function *ctor_function = llvm::dyn_cast<llvm::Function>(ctor_struct->getOperand(1)))
+                    {
+                        ctor_function->dump();
+
+                        ConstString ctor_function_name_cs(ctor_function->getName().str());
+                        
+                        for (JittedFunction &jitted_function : m_jitted_functions)
+                        {
+                            if (ctor_function_name_cs == jitted_function.m_name)
+                            {
+                                if (jitted_function.m_remote_addr != LLDB_INVALID_ADDRESS)
+                                {
+                                    static_initializers.push_back(jitted_function.m_remote_addr);
+                                }
+                                break;
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+uint64_t
+IRExecutionUnit::MemoryManager::getSymbolAddress(const std::string &Name)
+{
+    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
+
+    ConstString name_cs(Name.c_str());
+
+    lldb::addr_t ret = m_parent.FindSymbol(name_cs);
+
+    if (ret == LLDB_INVALID_ADDRESS)
     {
         if (log)
             log->Printf("IRExecutionUnit::getSymbolAddress(Name=\"%s\") = <not found>",
-                        name);
-        
-        m_parent.ReportSymbolLookupError(bare_name_cs);
-        
+                        Name.c_str());
+
+        m_parent.ReportSymbolLookupError(name_cs);
         return 0xbad0bad0;
     }
-    
-    if (log)
-        log->Printf("IRExecutionUnit::getSymbolAddress(Name=\"%s\") = %" PRIx64,
-                    name,
-                    symbol_load_addr);
-    
-    if (symbol_load_addr == 0)
-        return 0xbad00add;
-    
-    return symbol_load_addr;
+    else
+    {
+        if (log)
+            log->Printf("IRExecutionUnit::getSymbolAddress(Name=\"%s\") = %" PRIx64,
+                        Name.c_str(),
+                        ret);
+        return ret;
+    }
 }
 
 void *
 IRExecutionUnit::MemoryManager::getPointerToNamedFunction(const std::string &Name,
                                                           bool AbortOnFailure) {
     assert (sizeof(void *) == 8);
-    
+
     return (void*)getSymbolAddress(Name);
 }
 
@@ -787,19 +1181,17 @@ IRExecutionUnit::GetRemoteRangeForLocal (lldb::addr_t local_address)
 }
 
 bool
-IRExecutionUnit::CommitAllocations (lldb::ProcessSP &process_sp)
+IRExecutionUnit::CommitOneAllocation (lldb::ProcessSP &process_sp,
+                                      Error &error,
+                                      AllocationRecord &record)
 {
-    bool ret = true;
-
-    lldb_private::Error err;
-
-    for (AllocationRecord &record : m_records)
+    if (record.m_process_address != LLDB_INVALID_ADDRESS)
+    {
+        return true;
+    }
+    
+    switch (record.m_sect_type)
     {
-        if (record.m_process_address != LLDB_INVALID_ADDRESS)
-            continue;
-
-        switch (record.m_sect_type)
-        {
         case lldb::eSectionTypeInvalid:
         case lldb::eSectionTypeDWARFDebugAbbrev:
         case lldb::eSectionTypeDWARFDebugAddr:
@@ -818,7 +1210,7 @@ IRExecutionUnit::CommitAllocations (lldb::ProcessSP &process_sp)
         case lldb::eSectionTypeDWARFAppleTypes:
         case lldb::eSectionTypeDWARFAppleNamespaces:
         case lldb::eSectionTypeDWARFAppleObjC:
-            err.Clear();
+            error.Clear();
             break;
         default:
             const bool zero_memory = false;
@@ -827,13 +1219,26 @@ IRExecutionUnit::CommitAllocations (lldb::ProcessSP &process_sp)
                                                record.m_permissions,
                                                eAllocationPolicyProcessOnly,
                                                zero_memory,
-                                               err);
+                                               error);
             break;
-        }
+    }
+    
+    return error.Success();
+}
 
-        if (!err.Success())
+bool
+IRExecutionUnit::CommitAllocations (lldb::ProcessSP &process_sp)
+{
+    bool ret = true;
+
+    lldb_private::Error err;
+
+    for (AllocationRecord &record : m_records)
+    {
+        ret = CommitOneAllocation(process_sp, err, record);
+        
+        if (!ret)
         {
-            ret = false;
             break;
         }
     }
@@ -856,6 +1261,8 @@ IRExecutionUnit::CommitAllocations (lldb::ProcessSP &process_sp)
 void
 IRExecutionUnit::ReportAllocations (llvm::ExecutionEngine &engine)
 {
+    m_reported_allocations = true;
+    
     for (AllocationRecord &record : m_records)
     {
         if (record.m_process_address == LLDB_INVALID_ADDRESS)
diff --git a/source/Expression/IRInterpreter.cpp b/source/Expression/IRInterpreter.cpp
index a2b0c5b86851d..0285248314b67 100644
--- a/source/Expression/IRInterpreter.cpp
+++ b/source/Expression/IRInterpreter.cpp
@@ -7,16 +7,19 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "lldb/Expression/IRInterpreter.h"
+#include "lldb/Core/ConstString.h"
 #include "lldb/Core/DataExtractor.h"
 #include "lldb/Core/Error.h"
 #include "lldb/Core/Log.h"
-#include "lldb/Core/ModuleSpec.h"
 #include "lldb/Core/Module.h"
+#include "lldb/Core/ModuleSpec.h"
 #include "lldb/Core/Scalar.h"
 #include "lldb/Core/StreamString.h"
 #include "lldb/Core/ValueObject.h"
+#include "lldb/Expression/DiagnosticManager.h"
+#include "lldb/Expression/IRExecutionUnit.h"
 #include "lldb/Expression/IRMemoryMap.h"
-#include "lldb/Expression/IRInterpreter.h"
 #include "lldb/Host/Endian.h"
 
 #include "lldb/Target/ABI.h"
@@ -33,6 +36,7 @@
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
+#include "llvm/IR/Operator.h"
 #include "llvm/Support/raw_ostream.h"
 
 #include <map>
@@ -100,8 +104,9 @@ public:
 
     ValueMap                                m_values;
     DataLayout                             &m_target_data;
-    lldb_private::IRMemoryMap              &m_memory_map;
+    lldb_private::IRExecutionUnit          &m_execution_unit;
     const BasicBlock                       *m_bb;
+    const BasicBlock                       *m_prev_bb;
     BasicBlock::const_iterator              m_ii;
     BasicBlock::const_iterator              m_ie;
 
@@ -113,11 +118,13 @@ public:
     size_t                                  m_addr_byte_size;
 
     InterpreterStackFrame (DataLayout &target_data,
-                           lldb_private::IRMemoryMap &memory_map,
+                           lldb_private::IRExecutionUnit &execution_unit,
                            lldb::addr_t stack_frame_bottom,
                            lldb::addr_t stack_frame_top) :
         m_target_data (target_data),
-        m_memory_map (memory_map)
+        m_execution_unit (execution_unit),
+        m_bb (nullptr),
+        m_prev_bb (nullptr)
     {
         m_byte_order = (target_data.isLittleEndian() ? lldb::eByteOrderLittle : lldb::eByteOrderBig);
         m_addr_byte_size = (target_data.getPointerSize(0));
@@ -133,6 +140,7 @@ public:
 
     void Jump (const BasicBlock *bb)
     {
+        m_prev_bb = m_bb;
         m_bb = bb;
         m_ii = m_bb->begin();
         m_ie = m_bb->end();
@@ -202,7 +210,7 @@ public:
             lldb_private::DataExtractor value_extractor;
             lldb_private::Error extract_error;
 
-            m_memory_map.GetMemoryData(value_extractor, process_address, value_size, extract_error);
+            m_execution_unit.GetMemoryData(value_extractor, process_address, value_size, extract_error);
 
             if (!extract_error.Success())
                 return false;
@@ -227,7 +235,7 @@ public:
 
         lldb_private::Scalar cast_scalar;
 
-        if (!AssignToMatchType(cast_scalar, scalar.GetRawBits64(0), value->getType()))
+        if (!AssignToMatchType(cast_scalar, scalar.ULongLong(), value->getType()))
             return false;
 
         size_t value_byte_size = m_target_data.getTypeStoreSize(value->getType());
@@ -241,7 +249,7 @@ public:
 
         lldb_private::Error write_error;
 
-        m_memory_map.WriteMemory(process_address, buf.GetBytes(), buf.GetByteSize(), write_error);
+        m_execution_unit.WriteMemory(process_address, buf.GetBytes(), buf.GetByteSize(), write_error);
 
         return write_error.Success();
     }
@@ -252,6 +260,17 @@ public:
         {
         default:
             break;
+        case Value::FunctionVal:
+            if (const Function *constant_func = dyn_cast<Function>(constant))
+            {
+                lldb_private::ConstString name(constant_func->getName());
+                lldb::addr_t addr = m_execution_unit.FindSymbol(name);
+                if (addr == LLDB_INVALID_ADDRESS)
+                    return false;
+                value = APInt(m_target_data.getPointerSizeInBits(), addr);
+                return true;
+            }
+            break;
         case Value::ConstantIntVal:
             if (const ConstantInt *constant_int = dyn_cast<ConstantInt>(constant))
             {
@@ -297,7 +316,8 @@ public:
 
                         SmallVector <Value *, 8> indices (op_cursor, op_end);
 
-                        uint64_t offset = m_target_data.getIndexedOffset(base->getType(), indices);
+                        Type *src_elem_ty = cast<GEPOperator>(constant_expr)->getSourceElementType();
+                        uint64_t offset = m_target_data.getIndexedOffsetInType(src_elem_ty, indices);
 
                         const bool is_signed = true;
                         value += APInt(value.getBitWidth(), offset, is_signed);
@@ -327,12 +347,12 @@ public:
 
         lldb_private::Error write_error;
 
-        m_memory_map.WritePointerToMemory(data_address, address, write_error);
+        m_execution_unit.WritePointerToMemory(data_address, address, write_error);
 
         if (!write_error.Success())
         {
             lldb_private::Error free_error;
-            m_memory_map.Free(data_address, free_error);
+            m_execution_unit.Free(data_address, free_error);
             return false;
         }
 
@@ -357,19 +377,18 @@ public:
         if (!ResolveConstantValue(resolved_value, constant))
             return false;
 
-        lldb_private::StreamString buffer (lldb_private::Stream::eBinary,
-                                           m_memory_map.GetAddressByteSize(),
-                                           m_memory_map.GetByteOrder());
-
         size_t constant_size = m_target_data.getTypeStoreSize(constant->getType());
+        lldb_private::DataBufferHeap buf(constant_size, 0);
 
-        const uint64_t *raw_data = resolved_value.getRawData();
+        lldb_private::Error get_data_error;
 
-        buffer.PutRawBytes(raw_data, constant_size, lldb_private::endian::InlHostByteOrder());
+        lldb_private::Scalar resolved_scalar(resolved_value.zextOrTrunc(llvm::NextPowerOf2(constant_size) * 8));
+        if (!resolved_scalar.GetAsMemoryData(buf.GetBytes(), buf.GetByteSize(), m_byte_order, get_data_error))
+            return false;
 
         lldb_private::Error write_error;
 
-        m_memory_map.WriteMemory(process_address, (const uint8_t*)buffer.GetData(), constant_size, write_error);
+        m_execution_unit.WriteMemory(process_address, buf.GetBytes(), buf.GetByteSize(), write_error);
 
         return write_error.Success();
     }
@@ -408,7 +427,7 @@ public:
 
         lldb_private::Error read_error;
 
-        m_memory_map.ReadMemory(buf.GetBytes(), addr, length, read_error);
+        m_execution_unit.ReadMemory(buf.GetBytes(), addr, length, read_error);
 
         if (!read_error.Success())
             return std::string("<couldn't read data>");
@@ -442,7 +461,7 @@ public:
             if (!ResolveConstant (data_address, constant))
             {
                 lldb_private::Error free_error;
-                m_memory_map.Free(data_address, free_error);
+                m_execution_unit.Free(data_address, free_error);
                 return LLDB_INVALID_ADDRESS;
             }
         }
@@ -462,6 +481,47 @@ static const char *memory_write_error               = "Interpreter couldn't writ
 static const char *memory_read_error                = "Interpreter couldn't read from memory";
 static const char *infinite_loop_error              = "Interpreter ran for too many cycles";
 //static const char *bad_result_error                 = "Result of expression is in bad memory";
+static const char *too_many_functions_error = "Interpreter doesn't handle modules with multiple function bodies.";
+
+static bool
+CanResolveConstant (llvm::Constant *constant)
+{
+    switch (constant->getValueID())
+    {
+    default:
+        return false;
+    case Value::ConstantIntVal:
+    case Value::ConstantFPVal:
+    case Value::FunctionVal:
+        return true;
+    case Value::ConstantExprVal:
+        if (const ConstantExpr *constant_expr = dyn_cast<ConstantExpr>(constant))
+        {
+            switch (constant_expr->getOpcode())
+            {
+                default:
+                    return false;
+                case Instruction::IntToPtr:
+                case Instruction::PtrToInt:
+                case Instruction::BitCast:
+                    return CanResolveConstant(constant_expr->getOperand(0));
+                case Instruction::GetElementPtr:
+                {
+                    ConstantExpr::const_op_iterator op_cursor = constant_expr->op_begin();
+                    Constant *base = dyn_cast<Constant>(*op_cursor);
+                    if (!base)
+                        return false;
+
+                    return CanResolveConstant(base);
+                }
+            }
+        } else {
+            return false;
+        }
+    case Value::ConstantPointerNullVal:
+        return true;
+    }
+}
 
 bool
 IRInterpreter::CanInterpret (llvm::Module &module,
@@ -480,7 +540,13 @@ IRInterpreter::CanInterpret (llvm::Module &module,
         if (fi->begin() != fi->end())
         {
             if (saw_function_with_body)
+            {
+                if (log)
+                    log->Printf("More than one function in the module has a body");
+                error.SetErrorToGenericError();
+                error.SetErrorString(too_many_functions_error);
                 return false;
+            }
             saw_function_with_body = true;
         }
     }
@@ -507,6 +573,7 @@ IRInterpreter::CanInterpret (llvm::Module &module,
             case Instruction::Alloca:
             case Instruction::BitCast:
             case Instruction::Br:
+            case Instruction::PHI:
                 break;
             case Instruction::Call:
                 {
@@ -609,18 +676,30 @@ IRInterpreter::CanInterpret (llvm::Module &module,
                         return false;
                     }
                 }
+
+                if (Constant *constant = llvm::dyn_cast<Constant>(operand))
+                {
+                    if (!CanResolveConstant(constant))
+                    {
+                        if (log)
+                            log->Printf("Unsupported constant: %s", PrintValue(constant).c_str());
+                        error.SetErrorString(unsupported_operand_error);
+                        return false;
+                    }
+                }
             }
         }
 
     }
 
-    return true;}
+    return true;
+}
 
 bool
 IRInterpreter::Interpret (llvm::Module &module,
                           llvm::Function &function,
                           llvm::ArrayRef<lldb::addr_t> args,
-                          lldb_private::IRMemoryMap &memory_map,
+                          lldb_private::IRExecutionUnit &execution_unit,
                           lldb_private::Error &error,
                           lldb::addr_t stack_frame_bottom,
                           lldb::addr_t stack_frame_top,
@@ -642,7 +721,7 @@ IRInterpreter::Interpret (llvm::Module &module,
 
     DataLayout data_layout(&module);
 
-    InterpreterStackFrame frame(data_layout, memory_map, stack_frame_bottom, stack_frame_top);
+    InterpreterStackFrame frame(data_layout, execution_unit, stack_frame_bottom, stack_frame_top);
 
     if (frame.m_frame_process_address == LLDB_INVALID_ADDRESS)
     {
@@ -752,7 +831,9 @@ IRInterpreter::Interpret (llvm::Module &module,
                         result = L / R;
                         break;
                     case Instruction::UDiv:
-                        result = L.GetRawBits64(0) / R.GetRawBits64(1);
+                        L.MakeUnsigned();
+                        R.MakeUnsigned();
+                        result = L / R;
                         break;
                     case Instruction::SRem:
                         L.MakeSigned();
@@ -760,7 +841,9 @@ IRInterpreter::Interpret (llvm::Module &module,
                         result = L % R;
                         break;
                     case Instruction::URem:
-                        result = L.GetRawBits64(0) % R.GetRawBits64(1);
+                        L.MakeUnsigned();
+                        R.MakeUnsigned();
+                        result = L % R;
                         break;
                     case Instruction::Shl:
                         result = L << R;
@@ -848,7 +931,7 @@ IRInterpreter::Interpret (llvm::Module &module,
 
                 lldb_private::Error write_error;
 
-                memory_map.WritePointerToMemory(P, R, write_error);
+                execution_unit.WritePointerToMemory(P, R, write_error);
 
                 if (!write_error.Success())
                 {
@@ -857,8 +940,8 @@ IRInterpreter::Interpret (llvm::Module &module,
                     error.SetErrorToGenericError();
                     error.SetErrorString(memory_write_error);
                     lldb_private::Error free_error;
-                    memory_map.Free(P, free_error);
-                    memory_map.Free(R, free_error);
+                    execution_unit.Free(P, free_error);
+                    execution_unit.Free(R, free_error);
                     return false;
                 }
 
@@ -963,7 +1046,7 @@ IRInterpreter::Interpret (llvm::Module &module,
                         return false;
                     }
 
-                    if (C.GetRawBits64(0))
+                    if (!C.IsZero())
                         frame.Jump(br_inst->getSuccessor(0));
                     else
                         frame.Jump(br_inst->getSuccessor(1));
@@ -985,6 +1068,46 @@ IRInterpreter::Interpret (llvm::Module &module,
                 }
             }
                 continue;
+            case Instruction::PHI:
+            {
+                const PHINode *phi_inst = dyn_cast<PHINode>(inst);
+
+                if (!phi_inst)
+                {
+                    if (log)
+                        log->Printf("getOpcode() returns PHI, but instruction is not a PHINode");
+                    error.SetErrorToGenericError();
+                    error.SetErrorString(interpreter_internal_error);
+                    return false;
+                }
+                if (!frame.m_prev_bb)
+                {
+                    if (log)
+                        log->Printf("Encountered PHI node without having jumped from another basic block");
+                    error.SetErrorToGenericError();
+                    error.SetErrorString(interpreter_internal_error);
+                    return false;
+                }
+
+                Value* value = phi_inst->getIncomingValueForBlock(frame.m_prev_bb);
+                lldb_private::Scalar result;
+                if (!frame.EvaluateValue(result, value, module))
+                {
+                    if (log)
+                        log->Printf("Couldn't evaluate %s", PrintValue(value).c_str());
+                    error.SetErrorToGenericError();
+                    error.SetErrorString(bad_value_error);
+                    return false;
+                }
+                frame.AssignValue(inst, result, module);
+
+                if (log)
+                {
+                    log->Printf("Interpreted a %s", inst->getOpcodeName());
+                    log->Printf("  Incoming value : %s", frame.SummarizeValue(value).c_str());
+                }
+            }
+            break;
             case Instruction::GetElementPtr:
             {
                 const GetElementPtrInst *gep_inst = dyn_cast<GetElementPtrInst>(inst);
@@ -999,7 +1122,7 @@ IRInterpreter::Interpret (llvm::Module &module,
                 }
 
                 const Value *pointer_operand = gep_inst->getPointerOperand();
-                Type *pointer_type = pointer_operand->getType();
+                Type *src_elem_ty = gep_inst->getSourceElementType();
 
                 lldb_private::Scalar P;
 
@@ -1048,7 +1171,7 @@ IRInterpreter::Interpret (llvm::Module &module,
                     const_indices.push_back(constant_index);
                 }
 
-                uint64_t offset = data_layout.getIndexedOffset(pointer_type, const_indices);
+                uint64_t offset = data_layout.getIndexedOffsetInType(src_elem_ty, const_indices);
 
                 lldb_private::Scalar Poffset = P + offset;
 
@@ -1114,16 +1237,24 @@ IRInterpreter::Interpret (llvm::Module &module,
                         result = (L != R);
                         break;
                     case CmpInst::ICMP_UGT:
-                        result = (L.GetRawBits64(0) > R.GetRawBits64(0));
+                        L.MakeUnsigned();
+                        R.MakeUnsigned();
+                        result = (L > R);
                         break;
                     case CmpInst::ICMP_UGE:
-                        result = (L.GetRawBits64(0) >= R.GetRawBits64(0));
+                        L.MakeUnsigned();
+                        R.MakeUnsigned();
+                        result = (L >= R);
                         break;
                     case CmpInst::ICMP_ULT:
-                        result = (L.GetRawBits64(0) < R.GetRawBits64(0));
+                        L.MakeUnsigned();
+                        R.MakeUnsigned();
+                        result = (L < R);
                         break;
                     case CmpInst::ICMP_ULE:
-                        result = (L.GetRawBits64(0) <= R.GetRawBits64(0));
+                        L.MakeUnsigned();
+                        R.MakeUnsigned();
+                        result = (L <= R);
                         break;
                     case CmpInst::ICMP_SGT:
                         L.MakeSigned();
@@ -1322,7 +1453,7 @@ IRInterpreter::Interpret (llvm::Module &module,
 
                 lldb::addr_t R;
                 lldb_private::Error read_error;
-                memory_map.ReadPointerFromMemory(&R, P, read_error);
+                execution_unit.ReadPointerFromMemory(&R, P, read_error);
 
                 if (!read_error.Success())
                 {
@@ -1337,7 +1468,7 @@ IRInterpreter::Interpret (llvm::Module &module,
                 lldb_private::DataBufferHeap buffer(target_size, 0);
 
                 read_error.Clear();
-                memory_map.ReadMemory(buffer.GetBytes(), R, buffer.GetByteSize(), read_error);
+                execution_unit.ReadMemory(buffer.GetBytes(), R, buffer.GetByteSize(), read_error);
                 if (!read_error.Success())
                 {
                     if (log)
@@ -1348,7 +1479,7 @@ IRInterpreter::Interpret (llvm::Module &module,
                 }
 
                 lldb_private::Error write_error;
-                memory_map.WriteMemory(D, buffer.GetBytes(), buffer.GetByteSize(), write_error);
+                execution_unit.WriteMemory(D, buffer.GetBytes(), buffer.GetByteSize(), write_error);
                 if (!write_error.Success())
                 {
                     if (log)
@@ -1422,7 +1553,7 @@ IRInterpreter::Interpret (llvm::Module &module,
 
                 lldb::addr_t R;
                 lldb_private::Error read_error;
-                memory_map.ReadPointerFromMemory(&R, P, read_error);
+                execution_unit.ReadPointerFromMemory(&R, P, read_error);
 
                 if (!read_error.Success())
                 {
@@ -1437,7 +1568,7 @@ IRInterpreter::Interpret (llvm::Module &module,
                 lldb_private::DataBufferHeap buffer(target_size, 0);
 
                 read_error.Clear();
-                memory_map.ReadMemory(buffer.GetBytes(), D, buffer.GetByteSize(), read_error);
+                execution_unit.ReadMemory(buffer.GetBytes(), D, buffer.GetByteSize(), read_error);
                 if (!read_error.Success())
                 {
                     if (log)
@@ -1448,7 +1579,7 @@ IRInterpreter::Interpret (llvm::Module &module,
                 }
 
                 lldb_private::Error write_error;
-                memory_map.WriteMemory(R, buffer.GetBytes(), buffer.GetByteSize(), write_error);
+                execution_unit.WriteMemory(R, buffer.GetBytes(), buffer.GetByteSize(), write_error);
                 if (!write_error.Success())
                 {
                     if (log)
@@ -1530,7 +1661,7 @@ IRInterpreter::Interpret (llvm::Module &module,
                 }
                 lldb_private::Address funcAddr(I.ULongLong(LLDB_INVALID_ADDRESS));
 
-                lldb_private::StreamString error_stream;
+                lldb_private::DiagnosticManager diagnostics;
                 lldb_private::EvaluateExpressionOptions options;
 
                 // We generally receive a function pointer which we must dereference
@@ -1597,14 +1728,14 @@ IRInterpreter::Interpret (llvm::Module &module,
                         lldb::addr_t addr = tmp_op.ULongLong();
                         size_t dataSize = 0;
 
-                        if (memory_map.GetAllocSize(addr, dataSize))
+                        if (execution_unit.GetAllocSize(addr, dataSize))
                         {
                             // Create the required buffer
                             rawArgs[i].size = dataSize;
                             rawArgs[i].data_ap.reset(new uint8_t[dataSize + 1]);
 
                             // Read string from host memory
-                            memory_map.ReadMemory(rawArgs[i].data_ap.get(), addr, dataSize, error);
+                            execution_unit.ReadMemory(rawArgs[i].data_ap.get(), addr, dataSize, error);
                             if (error.Fail())
                             {
                                 assert(!"we have failed to read the string from memory");
@@ -1635,31 +1766,24 @@ IRInterpreter::Interpret (llvm::Module &module,
                 llvm::ArrayRef<lldb_private::ABI::CallArgument> args(rawArgs, numArgs);
 
                 // Setup a thread plan to call the target function
-                lldb::ThreadPlanSP call_plan_sp
-                (
-                    new lldb_private::ThreadPlanCallFunctionUsingABI
-                    (
-                        exe_ctx.GetThreadRef(),
-                        funcAddr,
-                        *prototype,
-                        *returnType,
-                        args,
-                        options
-                    )
-                );
+                lldb::ThreadPlanSP call_plan_sp(new lldb_private::ThreadPlanCallFunctionUsingABI(
+                    exe_ctx.GetThreadRef(), funcAddr, *prototype, *returnType, args, options));
 
                 // Check if the plan is valid
-                if (!call_plan_sp || !call_plan_sp->ValidatePlan(&error_stream))
+                lldb_private::StreamString ss;
+                if (!call_plan_sp || !call_plan_sp->ValidatePlan(&ss))
                 {
                     error.SetErrorToGenericError();
-                    error.SetErrorStringWithFormat("unable to make ThreadPlanCallFunctionUsingABI for 0x%llx", I.ULongLong());
+                    error.SetErrorStringWithFormat("unable to make ThreadPlanCallFunctionUsingABI for 0x%llx",
+                                                   I.ULongLong());
                     return false;
                 }
 
                 exe_ctx.GetProcessPtr()->SetRunningUserExpression(true);
 
                 // Execute the actual function call thread plan
-                lldb::ExpressionResults res = exe_ctx.GetProcessRef().RunThreadPlan(exe_ctx, call_plan_sp, options, error_stream);
+                lldb::ExpressionResults res =
+                    exe_ctx.GetProcessRef().RunThreadPlan(exe_ctx, call_plan_sp, options, diagnostics);
 
                 // Check that the thread plan completed successfully
                 if (res != lldb::ExpressionResults::eExpressionCompleted)
diff --git a/source/Expression/IRMemoryMap.cpp b/source/Expression/IRMemoryMap.cpp
index e96bddde7cbb8..aa165722c437c 100644
--- a/source/Expression/IRMemoryMap.cpp
+++ b/source/Expression/IRMemoryMap.cpp
@@ -13,8 +13,10 @@
 #include "lldb/Core/Log.h"
 #include "lldb/Core/Scalar.h"
 #include "lldb/Expression/IRMemoryMap.h"
+#include "lldb/Target/MemoryRegionInfo.h"
 #include "lldb/Target/Process.h"
 #include "lldb/Target/Target.h"
+#include "lldb/Utility/LLDBAssert.h"
 
 using namespace lldb_private;
 
@@ -47,37 +49,136 @@ IRMemoryMap::~IRMemoryMap ()
 }
 
 lldb::addr_t
-IRMemoryMap::FindSpace (size_t size, bool zero_memory)
+IRMemoryMap::FindSpace (size_t size)
 {
+    // The FindSpace algorithm's job is to find a region of memory that the
+    // underlying process is unlikely to be using.
+    //
+    // The memory returned by this function will never be written to.  The only
+    // point is that it should not shadow process memory if possible, so that
+    // expressions processing real values from the process do not use the
+    // wrong data.
+    //
+    // If the process can in fact allocate memory (CanJIT() lets us know this)
+    // then this can be accomplished just be allocating memory in the inferior.
+    // Then no guessing is required.
+
     lldb::TargetSP target_sp = m_target_wp.lock();
     lldb::ProcessSP process_sp = m_process_wp.lock();
+    
+    const bool process_is_alive = process_sp && process_sp->IsAlive();
 
     lldb::addr_t ret = LLDB_INVALID_ADDRESS;
     if (size == 0)
         return ret;
 
-    if (process_sp && process_sp->CanJIT() && process_sp->IsAlive())
+    if (process_is_alive && process_sp->CanJIT())
     {
         Error alloc_error;
 
-        if (!zero_memory)
-            ret = process_sp->AllocateMemory(size, lldb::ePermissionsReadable | lldb::ePermissionsWritable, alloc_error);
-        else
-            ret = process_sp->CallocateMemory(size, lldb::ePermissionsReadable | lldb::ePermissionsWritable, alloc_error);
+        ret = process_sp->AllocateMemory(size, lldb::ePermissionsReadable | lldb::ePermissionsWritable, alloc_error);
 
         if (!alloc_error.Success())
             return LLDB_INVALID_ADDRESS;
         else
             return ret;
     }
+    
+    // At this point we know that we need to hunt.
+    //
+    // First, go to the end of the existing allocations we've made if there are
+    // any allocations.  Otherwise start at the beginning of memory.
 
-    ret = 0;
-    if (!m_allocations.empty())
+    if (m_allocations.empty())
+    {
+        ret = 0x0;
+    }
+    else
+    {
+        auto back = m_allocations.rbegin();
+        lldb::addr_t addr = back->first;
+        size_t alloc_size = back->second.m_size;
+        ret = llvm::alignTo(addr+alloc_size, 4096);
+    }
+    
+    // Now, if it's possible to use the GetMemoryRegionInfo API to detect mapped
+    // regions, walk forward through memory until a region is found that
+    // has adequate space for our allocation.
+    if (process_is_alive)
+    {
+        const uint64_t end_of_memory = process_sp->GetAddressByteSize() == 8 ?
+            0xffffffffffffffffull : 0xffffffffull;
+        
+        lldbassert(process_sp->GetAddressByteSize() == 4 || end_of_memory != 0xffffffffull);
+        
+        MemoryRegionInfo region_info;
+        Error err = process_sp->GetMemoryRegionInfo(ret, region_info);
+        if (err.Success())
+        {
+            while (true)
+            {
+                if (region_info.GetReadable() != MemoryRegionInfo::OptionalBool::eNo ||
+                    region_info.GetWritable() != MemoryRegionInfo::OptionalBool::eNo ||
+                    region_info.GetExecutable() != MemoryRegionInfo::OptionalBool::eNo)
+                {
+                    if (region_info.GetRange().GetRangeEnd() - 1 >= end_of_memory)
+                    {
+                        ret = LLDB_INVALID_ADDRESS;
+                        break;
+                    }
+                    else
+                    {
+                        ret = region_info.GetRange().GetRangeEnd();
+                    }
+                }
+                else if (ret + size < region_info.GetRange().GetRangeEnd())
+                {
+                    return ret;
+                }
+                else
+                {
+                    // ret stays the same.  We just need to walk a bit further.
+                }
+                
+                err = process_sp->GetMemoryRegionInfo(region_info.GetRange().GetRangeEnd(), region_info);
+                if (err.Fail())
+                {
+                    lldbassert(!"GetMemoryRegionInfo() succeeded, then failed");
+                    ret = LLDB_INVALID_ADDRESS;
+                    break;
+                }
+            }
+        }
+    }
+    
+    // We've tried our algorithm, and it didn't work.  Now we have to reset back
+    // to the end of the allocations we've already reported, or use a 'sensible'
+    // default if this is our first allocation.
+    
+    if (m_allocations.empty())
+    {
+        uint32_t address_byte_size = GetAddressByteSize();
+        if (address_byte_size != UINT32_MAX)
+        {
+            switch (address_byte_size)
+            {
+                case 8:
+                    ret = 0xffffffff00000000ull;
+                    break;
+                case 4:
+                    ret = 0xee000000ull;
+                    break;
+                default:
+                    break;
+            }
+        }
+    }
+    else
     {
         auto back = m_allocations.rbegin();
         lldb::addr_t addr = back->first;
         size_t alloc_size = back->second.m_size;
-        ret = llvm::RoundUpToAlignment(addr+alloc_size, 4096);
+        ret = llvm::alignTo(addr+alloc_size, 4096);
     }
 
     return ret;
@@ -329,6 +430,13 @@ IRMemoryMap::Malloc (size_t size, uint8_t alignment, uint32_t permissions, Alloc
                                                 alignment,
                                                 policy);
 
+    if (zero_memory)
+    {
+        Error write_error;
+        std::vector<uint8_t> zero_buf(size, 0);
+        WriteMemory(aligned_address, zero_buf.data(), size, write_error);
+    }
+
     if (log)
     {
         const char * policy_string;
@@ -784,6 +892,7 @@ IRMemoryMap::GetMemoryData (DataExtractor &extractor, lldb::addr_t process_addre
                     return;
                 }
             }
+            break;
         case eAllocationPolicyHostOnly:
             if (!allocation.m_data.GetByteSize())
             {
diff --git a/source/Expression/LLVMUserExpression.cpp b/source/Expression/LLVMUserExpression.cpp
index eff0a2dc30d6d..0b969806280e7 100644
--- a/source/Expression/LLVMUserExpression.cpp
+++ b/source/Expression/LLVMUserExpression.cpp
@@ -18,6 +18,7 @@
 #include "lldb/Core/StreamFile.h"
 #include "lldb/Core/StreamString.h"
 #include "lldb/Core/ValueObjectConstResult.h"
+#include "lldb/Expression/DiagnosticManager.h"
 #include "lldb/Expression/ExpressionSourceCode.h"
 #include "lldb/Expression/IRExecutionUnit.h"
 #include "lldb/Expression/IRInterpreter.h"
@@ -25,11 +26,11 @@
 #include "lldb/Host/HostInfo.h"
 #include "lldb/Symbol/Block.h"
 #include "lldb/Symbol/ClangASTContext.h"
+#include "lldb/Symbol/ClangExternalASTSourceCommon.h"
 #include "lldb/Symbol/Function.h"
 #include "lldb/Symbol/ObjectFile.h"
 #include "lldb/Symbol/SymbolVendor.h"
 #include "lldb/Symbol/Type.h"
-#include "lldb/Symbol/ClangExternalASTSourceCommon.h"
 #include "lldb/Symbol/VariableList.h"
 #include "lldb/Target/ExecutionContext.h"
 #include "lldb/Target/Process.h"
@@ -58,7 +59,6 @@ LLVMUserExpression::LLVMUserExpression(ExecutionContextScope &exe_scope,
       m_in_objectivec_method(false),
       m_in_static_method(false),
       m_needs_object_ptr(false),
-      m_const_object(false),
       m_target(NULL),
       m_can_interpret(false),
       m_materialized_address(LLDB_INVALID_ADDRESS)
@@ -76,8 +76,9 @@ LLVMUserExpression::~LLVMUserExpression()
 }
 
 lldb::ExpressionResults
-LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, const EvaluateExpressionOptions &options,
-                            lldb::UserExpressionSP &shared_ptr_to_me, lldb::ExpressionVariableSP &result)
+LLVMUserExpression::DoExecute(DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx,
+                              const EvaluateExpressionOptions &options, lldb::UserExpressionSP &shared_ptr_to_me,
+                              lldb::ExpressionVariableSP &result)
 {
     // The expression log is quite verbose, and if you're just tracking the execution of the
     // expression, it's quite convenient to have these logs come out with the STEP log as well.
@@ -87,9 +88,10 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
     {
         lldb::addr_t struct_address = LLDB_INVALID_ADDRESS;
 
-        if (!PrepareToExecuteJITExpression(error_stream, exe_ctx, struct_address))
+        if (!PrepareToExecuteJITExpression(diagnostic_manager, exe_ctx, struct_address))
         {
-            error_stream.Printf("Errored out in %s, couldn't PrepareToExecuteJITExpression", __FUNCTION__);
+            diagnostic_manager.Printf(eDiagnosticSeverityError,
+                                      "errored out in %s, couldn't PrepareToExecuteJITExpression", __FUNCTION__);
             return lldb::eExpressionSetupError;
         }
 
@@ -103,7 +105,7 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
 
             if (!module || !function)
             {
-                error_stream.Printf("Supposed to interpret, but nothing is there");
+                diagnostic_manager.PutCString(eDiagnosticSeverityError, "supposed to interpret, but nothing is there");
                 return lldb::eExpressionSetupError;
             }
 
@@ -111,9 +113,10 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
 
             std::vector<lldb::addr_t> args;
 
-            if (!AddArguments(exe_ctx, args, struct_address, error_stream))
+            if (!AddArguments(exe_ctx, args, struct_address, diagnostic_manager))
             {
-                error_stream.Printf("Errored out in %s, couldn't AddArguments", __FUNCTION__);
+                diagnostic_manager.Printf(eDiagnosticSeverityError, "errored out in %s, couldn't AddArguments",
+                                          __FUNCTION__);
                 return lldb::eExpressionSetupError;
             }
 
@@ -121,11 +124,12 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
             function_stack_top = m_stack_frame_top;
 
             IRInterpreter::Interpret(*module, *function, args, *m_execution_unit_sp.get(), interpreter_error,
-                                     function_stack_bottom, function_stack_top, exe_ctx);
+                function_stack_bottom, function_stack_top, exe_ctx);
 
             if (!interpreter_error.Success())
             {
-                error_stream.Printf("Supposed to interpret, but failed: %s", interpreter_error.AsCString());
+                diagnostic_manager.Printf(eDiagnosticSeverityError, "supposed to interpret, but failed: %s",
+                                          interpreter_error.AsCString());
                 return lldb::eExpressionDiscarded;
             }
         }
@@ -133,7 +137,7 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
         {
             if (!exe_ctx.HasThreadScope())
             {
-                error_stream.Printf("UserExpression::Execute called with no thread selected.");
+                diagnostic_manager.Printf(eDiagnosticSeverityError, "%s called with no thread selected", __FUNCTION__);
                 return lldb::eExpressionSetupError;
             }
 
@@ -141,17 +145,22 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
 
             std::vector<lldb::addr_t> args;
 
-            if (!AddArguments(exe_ctx, args, struct_address, error_stream))
+            if (!AddArguments(exe_ctx, args, struct_address, diagnostic_manager))
             {
-                error_stream.Printf("Errored out in %s, couldn't AddArguments", __FUNCTION__);
+                diagnostic_manager.Printf(eDiagnosticSeverityError, "errored out in %s, couldn't AddArguments",
+                                          __FUNCTION__);
                 return lldb::eExpressionSetupError;
             }
 
             lldb::ThreadPlanSP call_plan_sp(new ThreadPlanCallUserExpression(exe_ctx.GetThreadRef(), wrapper_address,
                                                                              args, options, shared_ptr_to_me));
 
-            if (!call_plan_sp || !call_plan_sp->ValidatePlan(&error_stream))
+            StreamString ss;
+            if (!call_plan_sp || !call_plan_sp->ValidatePlan(&ss))
+            {
+                diagnostic_manager.PutCString(eDiagnosticSeverityError, ss.GetData());
                 return lldb::eExpressionSetupError;
+            }
 
             ThreadPlanCallUserExpression *user_expression_plan =
                 static_cast<ThreadPlanCallUserExpression *>(call_plan_sp.get());
@@ -168,7 +177,7 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
                 exe_ctx.GetProcessPtr()->SetRunningUserExpression(true);
 
             lldb::ExpressionResults execution_result =
-                exe_ctx.GetProcessRef().RunThreadPlan(exe_ctx, call_plan_sp, options, error_stream);
+                exe_ctx.GetProcessRef().RunThreadPlan(exe_ctx, call_plan_sp, options, diagnostic_manager);
 
             if (exe_ctx.GetProcessPtr())
                 exe_ctx.GetProcessPtr()->SetRunningUserExpression(false);
@@ -187,20 +196,21 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
                         error_desc = real_stop_info_sp->GetDescription();
                 }
                 if (error_desc)
-                    error_stream.Printf("Execution was interrupted, reason: %s.", error_desc);
+                    diagnostic_manager.Printf(eDiagnosticSeverityError, "Execution was interrupted, reason: %s.",
+                                              error_desc);
                 else
-                    error_stream.PutCString("Execution was interrupted.");
+                    diagnostic_manager.PutCString(eDiagnosticSeverityError, "Execution was interrupted.");
 
                 if ((execution_result == lldb::eExpressionInterrupted && options.DoesUnwindOnError()) ||
                     (execution_result == lldb::eExpressionHitBreakpoint && options.DoesIgnoreBreakpoints()))
-                    error_stream.PutCString(
-                        "\nThe process has been returned to the state before expression evaluation.");
+                    diagnostic_manager.AppendMessageToDiagnostic(
+                        "The process has been returned to the state before expression evaluation.");
                 else
                 {
                     if (execution_result == lldb::eExpressionHitBreakpoint)
                         user_expression_plan->TransferExpressionOwnership();
-                    error_stream.PutCString(
-                        "\nThe process has been left at the point where it was interrupted, "
+                    diagnostic_manager.AppendMessageToDiagnostic(
+                        "The process has been left at the point where it was interrupted, "
                         "use \"thread return -x\" to return to the state before expression evaluation.");
                 }
 
@@ -208,7 +218,8 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
             }
             else if (execution_result == lldb::eExpressionStoppedForDebug)
             {
-                error_stream.PutCString(
+                diagnostic_manager.PutCString(
+                    eDiagnosticSeverityRemark,
                     "Execution was halted at the first instruction of the expression "
                     "function because \"debug\" was requested.\n"
                     "Use \"thread return -x\" to return to the state before expression evaluation.");
@@ -216,13 +227,13 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
             }
             else if (execution_result != lldb::eExpressionCompleted)
             {
-                error_stream.Printf("Couldn't execute function; result was %s\n",
-                                    Process::ExecutionResultAsCString(execution_result));
+                diagnostic_manager.Printf(eDiagnosticSeverityError, "Couldn't execute function; result was %s",
+                                          Process::ExecutionResultAsCString(execution_result));
                 return execution_result;
             }
         }
 
-        if (FinalizeJITExecution(error_stream, exe_ctx, result, function_stack_bottom, function_stack_top))
+        if (FinalizeJITExecution(diagnostic_manager, exe_ctx, result, function_stack_bottom, function_stack_top))
         {
             return lldb::eExpressionCompleted;
         }
@@ -233,13 +244,14 @@ LLVMUserExpression::Execute(Stream &error_stream, ExecutionContext &exe_ctx, con
     }
     else
     {
-        error_stream.Printf("Expression can't be run, because there is no JIT compiled function");
+        diagnostic_manager.PutCString(eDiagnosticSeverityError,
+                                      "Expression can't be run, because there is no JIT compiled function");
         return lldb::eExpressionSetupError;
     }
 }
 
 bool
-LLVMUserExpression::FinalizeJITExecution(Stream &error_stream, ExecutionContext &exe_ctx,
+LLVMUserExpression::FinalizeJITExecution(DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx,
                                          lldb::ExpressionVariableSP &result, lldb::addr_t function_stack_bottom,
                                          lldb::addr_t function_stack_top)
 {
@@ -250,7 +262,8 @@ LLVMUserExpression::FinalizeJITExecution(Stream &error_stream, ExecutionContext
 
     if (!m_dematerializer_sp)
     {
-        error_stream.Printf("Couldn't apply expression side effects : no dematerializer is present");
+        diagnostic_manager.Printf(eDiagnosticSeverityError,
+                                  "Couldn't apply expression side effects : no dematerializer is present");
         return false;
     }
 
@@ -260,8 +273,8 @@ LLVMUserExpression::FinalizeJITExecution(Stream &error_stream, ExecutionContext
 
     if (!dematerialize_error.Success())
     {
-        error_stream.Printf("Couldn't apply expression side effects : %s\n",
-                            dematerialize_error.AsCString("unknown error"));
+        diagnostic_manager.Printf(eDiagnosticSeverityError, "Couldn't apply expression side effects : %s",
+                                  dematerialize_error.AsCString("unknown error"));
         return false;
     }
 
@@ -276,7 +289,7 @@ LLVMUserExpression::FinalizeJITExecution(Stream &error_stream, ExecutionContext
 }
 
 bool
-LLVMUserExpression::PrepareToExecuteJITExpression(Stream &error_stream, ExecutionContext &exe_ctx,
+LLVMUserExpression::PrepareToExecuteJITExpression(DiagnosticManager &diagnostic_manager, ExecutionContext &exe_ctx,
                                                   lldb::addr_t &struct_address)
 {
     lldb::TargetSP target;
@@ -285,7 +298,8 @@ LLVMUserExpression::PrepareToExecuteJITExpression(Stream &error_stream, Executio
 
     if (!LockAndCheckContext(exe_ctx, target, process, frame))
     {
-        error_stream.Printf("The context has changed before we could JIT the expression!\n");
+        diagnostic_manager.PutCString(eDiagnosticSeverityError,
+                                      "The context has changed before we could JIT the expression!");
         return false;
     }
 
@@ -309,7 +323,9 @@ LLVMUserExpression::PrepareToExecuteJITExpression(Stream &error_stream, Executio
 
             if (!alloc_error.Success())
             {
-                error_stream.Printf("Couldn't allocate space for materialized struct: %s\n", alloc_error.AsCString());
+                diagnostic_manager.Printf(eDiagnosticSeverityError,
+                                          "Couldn't allocate space for materialized struct: %s",
+                                          alloc_error.AsCString());
                 return false;
             }
         }
@@ -335,7 +351,8 @@ LLVMUserExpression::PrepareToExecuteJITExpression(Stream &error_stream, Executio
 
             if (!alloc_error.Success())
             {
-                error_stream.Printf("Couldn't allocate space for the stack frame: %s\n", alloc_error.AsCString());
+                diagnostic_manager.Printf(eDiagnosticSeverityError, "Couldn't allocate space for the stack frame: %s",
+                                          alloc_error.AsCString());
                 return false;
             }
         }
@@ -347,7 +364,8 @@ LLVMUserExpression::PrepareToExecuteJITExpression(Stream &error_stream, Executio
 
         if (!materialize_error.Success())
         {
-            error_stream.Printf("Couldn't materialize: %s\n", materialize_error.AsCString());
+            diagnostic_manager.Printf(eDiagnosticSeverityError, "Couldn't materialize: %s",
+                                      materialize_error.AsCString());
             return false;
         }
     }
diff --git a/source/Expression/Makefile b/source/Expression/Makefile
deleted file mode 100644
index 495f094d39006..0000000000000
--- a/source/Expression/Makefile
+++ /dev/null
@@ -1,14 +0,0 @@
-##===- source/Expression/Makefile --------------------------*- Makefile -*-===##
-#
-#                     The LLVM Compiler Infrastructure
-#
-# This file is distributed under the University of Illinois Open Source
-# License. See LICENSE.TXT for details.
-#
-##===----------------------------------------------------------------------===##
-
-LLDB_LEVEL := ../..
-LIBRARYNAME := lldbExpression
-BUILD_ARCHIVE = 1
-
-include $(LLDB_LEVEL)/Makefile
diff --git a/source/Expression/Materializer.cpp b/source/Expression/Materializer.cpp
index 8d68b4f79819d..3575f5436d921 100644
--- a/source/Expression/Materializer.cpp
+++ b/source/Expression/Materializer.cpp
@@ -34,19 +34,19 @@ Materializer::AddStructMember (Entity &entity)
 {
     uint32_t size = entity.GetSize();
     uint32_t alignment = entity.GetAlignment();
-    
+
     uint32_t ret;
-    
+
     if (m_current_offset == 0)
         m_struct_alignment = alignment;
-    
+
     if (m_current_offset % alignment)
         m_current_offset += (alignment - (m_current_offset % alignment));
-    
+
     ret = m_current_offset;
-    
+
     m_current_offset += size;
-    
+
     return ret;
 }
 
@@ -54,15 +54,15 @@ void
 Materializer::Entity::SetSizeAndAlignmentFromType (CompilerType &type)
 {
     m_size = type.GetByteSize(nullptr);
-    
+
     uint32_t bit_alignment = type.GetTypeBitAlign();
-    
+
     if (bit_alignment % 8)
     {
         bit_alignment += 8;
         bit_alignment &= ~((uint32_t)0x111u);
     }
-    
+
     m_alignment = bit_alignment / 8;
 }
 
@@ -79,59 +79,59 @@ public:
         m_size = 8;
         m_alignment = 8;
     }
-    
+
     void MakeAllocation (IRMemoryMap &map, Error &err)
     {
         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
 
         // Allocate a spare memory area to store the persistent variable's contents.
-        
+
         Error allocate_error;
         const bool zero_memory = false;
-        
+
         lldb::addr_t mem = map.Malloc(m_persistent_variable_sp->GetByteSize(),
                                       8,
                                       lldb::ePermissionsReadable | lldb::ePermissionsWritable,
                                       IRMemoryMap::eAllocationPolicyMirror,
                                       zero_memory,
                                       allocate_error);
-        
+
         if (!allocate_error.Success())
         {
             err.SetErrorStringWithFormat("couldn't allocate a memory area to store %s: %s", m_persistent_variable_sp->GetName().GetCString(), allocate_error.AsCString());
             return;
         }
-        
+
         if (log)
             log->Printf("Allocated %s (0x%" PRIx64 ") successfully", m_persistent_variable_sp->GetName().GetCString(), mem);
-        
+
         // Put the location of the spare memory into the live data of the ValueObject.
-        
+
         m_persistent_variable_sp->m_live_sp = ValueObjectConstResult::Create (map.GetBestExecutionContextScope(),
                                                                               m_persistent_variable_sp->GetCompilerType(),
                                                                               m_persistent_variable_sp->GetName(),
                                                                               mem,
                                                                               eAddressTypeLoad,
                                                                               map.GetAddressByteSize());
-        
+
         // Clear the flag if the variable will never be deallocated.
-        
+
         if (m_persistent_variable_sp->m_flags & ExpressionVariable::EVKeepInTarget)
         {
             Error leak_error;
             map.Leak(mem, leak_error);
             m_persistent_variable_sp->m_flags &= ~ExpressionVariable::EVNeedsAllocation;
         }
-        
+
         // Write the contents of the variable to the area.
-        
+
         Error write_error;
-        
+
         map.WriteMemory (mem,
                          m_persistent_variable_sp->GetValueBytes(),
                          m_persistent_variable_sp->GetByteSize(),
                          write_error);
-        
+
         if (!write_error.Success())
         {
             err.SetErrorStringWithFormat ("couldn't write %s to the target: %s", m_persistent_variable_sp->GetName().AsCString(),
@@ -139,21 +139,21 @@ public:
             return;
         }
     }
-    
+
     void DestroyAllocation (IRMemoryMap &map, Error &err)
     {
         Error deallocate_error;
-        
+
         map.Free((lldb::addr_t)m_persistent_variable_sp->m_live_sp->GetValue().GetScalar().ULongLong(), deallocate_error);
-        
+
         m_persistent_variable_sp->m_live_sp.reset();
-            
+
         if (!deallocate_error.Success())
         {
             err.SetErrorStringWithFormat ("couldn't deallocate memory for %s: %s", m_persistent_variable_sp->GetName().GetCString(), deallocate_error.AsCString());
         }
     }
-    
+
     void Materialize(lldb::StackFrameSP &frame_sp,
                      IRMemoryMap &map,
                      lldb::addr_t process_address,
@@ -162,7 +162,7 @@ public:
         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
 
         const lldb::addr_t load_addr = process_address + m_offset;
-    
+
         if (log)
         {
             log->Printf("EntityPersistentVariable::Materialize [address = 0x%" PRIx64 ", m_name = %s, m_flags = 0x%hx]",
@@ -170,26 +170,26 @@ public:
                         m_persistent_variable_sp->GetName().AsCString(),
                         m_persistent_variable_sp->m_flags);
         }
-        
+
         if (m_persistent_variable_sp->m_flags & ExpressionVariable::EVNeedsAllocation)
         {
             MakeAllocation(map, err);
             m_persistent_variable_sp->m_flags |= ExpressionVariable::EVIsLLDBAllocated;
-            
+
             if (!err.Success())
                 return;
         }
-        
+
         if ((m_persistent_variable_sp->m_flags & ExpressionVariable::EVIsProgramReference && m_persistent_variable_sp->m_live_sp) ||
             m_persistent_variable_sp->m_flags & ExpressionVariable::EVIsLLDBAllocated)
         {
             Error write_error;
-                        
+
             map.WriteScalarToMemory(load_addr,
                                     m_persistent_variable_sp->m_live_sp->GetValue().GetScalar(),
                                     map.GetAddressByteSize(),
                                     write_error);
-            
+
             if (!write_error.Success())
             {
                 err.SetErrorStringWithFormat("couldn't write the location of %s to memory: %s", m_persistent_variable_sp->GetName().AsCString(), write_error.AsCString());
@@ -201,7 +201,7 @@ public:
             return;
         }
     }
-    
+
     void Dematerialize(lldb::StackFrameSP &frame_sp,
                        IRMemoryMap &map,
                        lldb::addr_t process_address,
@@ -210,7 +210,7 @@ public:
                        Error &err) override
     {
         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
-        
+
         const lldb::addr_t load_addr = process_address + m_offset;
 
         if (log)
@@ -220,7 +220,7 @@ public:
                         m_persistent_variable_sp->GetName().AsCString(),
                         m_persistent_variable_sp->m_flags);
         }
-        
+
         if (m_delegate)
         {
             m_delegate->DidDematerialize(m_persistent_variable_sp);
@@ -234,25 +234,25 @@ public:
             {
                 // If the reference comes from the program, then the ClangExpressionVariable's
                 // live variable data hasn't been set up yet.  Do this now.
-                
+
                 lldb::addr_t location;
                 Error read_error;
-                
+
                 map.ReadPointerFromMemory(&location, load_addr, read_error);
-                                
+
                 if (!read_error.Success())
                 {
                     err.SetErrorStringWithFormat("couldn't read the address of program-allocated variable %s: %s", m_persistent_variable_sp->GetName().GetCString(), read_error.AsCString());
                     return;
                 }
-                
+
                 m_persistent_variable_sp->m_live_sp = ValueObjectConstResult::Create (map.GetBestExecutionContextScope (),
                                                                                       m_persistent_variable_sp.get()->GetCompilerType(),
                                                                                       m_persistent_variable_sp->GetName(),
                                                                                       location,
                                                                                       eAddressTypeLoad,
                                                                                       m_persistent_variable_sp->GetByteSize());
-                
+
                 if (frame_top != LLDB_INVALID_ADDRESS &&
                     frame_bottom != LLDB_INVALID_ADDRESS &&
                     location >= frame_bottom &&
@@ -267,44 +267,44 @@ public:
                     m_persistent_variable_sp->m_flags &= ~ExpressionVariable::EVIsProgramReference;
                 }
             }
-            
+
             lldb::addr_t mem = m_persistent_variable_sp->m_live_sp->GetValue().GetScalar().ULongLong();
-            
+
             if (!m_persistent_variable_sp->m_live_sp)
             {
                 err.SetErrorStringWithFormat("couldn't find the memory area used to store %s", m_persistent_variable_sp->GetName().GetCString());
                 return;
             }
-            
+
             if (m_persistent_variable_sp->m_live_sp->GetValue().GetValueAddressType() != eAddressTypeLoad)
             {
                 err.SetErrorStringWithFormat("the address of the memory area for %s is in an incorrect format", m_persistent_variable_sp->GetName().GetCString());
                 return;
             }
-            
+
             if (m_persistent_variable_sp->m_flags & ExpressionVariable::EVNeedsFreezeDry ||
                 m_persistent_variable_sp->m_flags & ExpressionVariable::EVKeepInTarget)
-            {                
+            {
                 if (log)
                     log->Printf("Dematerializing %s from 0x%" PRIx64 " (size = %llu)", m_persistent_variable_sp->GetName().GetCString(), (uint64_t)mem, (unsigned long long)m_persistent_variable_sp->GetByteSize());
-                
+
                 // Read the contents of the spare memory area
-                
+
                 m_persistent_variable_sp->ValueUpdated ();
-                
+
                 Error read_error;
-                
+
                 map.ReadMemory(m_persistent_variable_sp->GetValueBytes(),
                                mem,
                                m_persistent_variable_sp->GetByteSize(),
                                read_error);
-                
+
                 if (!read_error.Success())
                 {
                     err.SetErrorStringWithFormat ("couldn't read the contents of %s from memory: %s", m_persistent_variable_sp->GetName().GetCString(), read_error.AsCString());
                     return;
                 }
-                    
+
                 m_persistent_variable_sp->m_flags &= ~ExpressionVariable::EVNeedsFreezeDry;
             }
         }
@@ -313,13 +313,13 @@ public:
             err.SetErrorStringWithFormat("no dematerialization happened for persistent variable %s", m_persistent_variable_sp->GetName().AsCString());
             return;
         }
-        
+
         lldb::ProcessSP process_sp = map.GetBestExecutionContextScope()->CalculateProcess();
         if (!process_sp ||
             !process_sp->CanJIT())
         {
             // Allocations are not persistent so persistent variables cannot stay materialized.
-            
+
             m_persistent_variable_sp->m_flags |= ExpressionVariable::EVNeedsAllocation;
 
             DestroyAllocation(map, err);
@@ -334,24 +334,24 @@ public:
                 return;
         }
     }
-    
+
     void DumpToLog(IRMemoryMap &map, lldb::addr_t process_address, Log *log) override
     {
         StreamString dump_stream;
-        
+
         Error err;
-        
+
         const lldb::addr_t load_addr = process_address + m_offset;
 
         dump_stream.Printf("0x%" PRIx64 ": EntityPersistentVariable (%s)\n", load_addr, m_persistent_variable_sp->GetName().AsCString());
-        
+
         {
             dump_stream.Printf("Pointer:\n");
-            
+
             DataBufferHeap data (m_size, 0);
-            
+
             map.ReadMemory(data.GetBytes(), load_addr, m_size, err);
-            
+
             if (!err.Success())
             {
                 dump_stream.Printf("  <could not be read>\n");
@@ -359,20 +359,20 @@ public:
             else
             {
                 DataExtractor extractor (data.GetBytes(), data.GetByteSize(), map.GetByteOrder(), map.GetAddressByteSize());
-                
+
                 extractor.DumpHexBytes(&dump_stream, data.GetBytes(), data.GetByteSize(), 16, load_addr);
-                
+
                 dump_stream.PutChar('\n');
             }
         }
-        
+
         {
             dump_stream.Printf("Target:\n");
-            
+
             lldb::addr_t target_address;
-            
+
             map.ReadPointerFromMemory (&target_address, load_addr, err);
-                        
+
             if (!err.Success())
             {
                 dump_stream.Printf("  <could not be read>\n");
@@ -380,9 +380,9 @@ public:
             else
             {
                 DataBufferHeap data (m_persistent_variable_sp->GetByteSize(), 0);
-            
+
                 map.ReadMemory(data.GetBytes(), target_address, m_persistent_variable_sp->GetByteSize(), err);
-                
+
                 if (!err.Success())
                 {
                     dump_stream.Printf("  <could not be read>\n");
@@ -390,17 +390,17 @@ public:
                 else
                 {
                     DataExtractor extractor (data.GetBytes(), data.GetByteSize(), map.GetByteOrder(), map.GetAddressByteSize());
-                    
+
                     extractor.DumpHexBytes(&dump_stream, data.GetBytes(), data.GetByteSize(), 16, target_address);
-                    
+
                     dump_stream.PutChar('\n');
                 }
             }
         }
-        
+
         log->PutCString(dump_stream.GetData());
     }
-    
+
     void Wipe(IRMemoryMap &map, lldb::addr_t process_address) override
     {
     }
@@ -437,14 +437,14 @@ public:
         m_alignment = 8;
         m_is_reference = m_variable_sp->GetType()->GetForwardCompilerType ().IsReferenceType();
     }
-    
+
     void Materialize(lldb::StackFrameSP &frame_sp,
                      IRMemoryMap &map,
                      lldb::addr_t process_address,
                      Error &err) override
     {
         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
-        
+
         const lldb::addr_t load_addr = process_address + m_offset;
         if (log)
         {
@@ -452,46 +452,46 @@ public:
                         (uint64_t)load_addr,
                         m_variable_sp->GetName().AsCString());
         }
-        
+
         ExecutionContextScope *scope = frame_sp.get();
-        
+
         if (!scope)
             scope = map.GetBestExecutionContextScope();
-        
+
         lldb::ValueObjectSP valobj_sp = ValueObjectVariable::Create(scope, m_variable_sp);
-        
+
         if (!valobj_sp)
         {
             err.SetErrorStringWithFormat("couldn't get a value object for variable %s", m_variable_sp->GetName().AsCString());
             return;
         }
-        
+
         Error valobj_error = valobj_sp->GetError();
-        
+
         if (valobj_error.Fail())
         {
             err.SetErrorStringWithFormat("couldn't get the value of variable %s: %s", m_variable_sp->GetName().AsCString(), valobj_error.AsCString());
             return;
         }
-        
+
         if (m_is_reference)
         {
             DataExtractor valobj_extractor;
             Error extract_error;
             valobj_sp->GetData(valobj_extractor, extract_error);
-            
+
             if (!extract_error.Success())
             {
                 err.SetErrorStringWithFormat("couldn't read contents of reference variable %s: %s", m_variable_sp->GetName().AsCString(), extract_error.AsCString());
                 return;
             }
-            
+
             lldb::offset_t offset = 0;
             lldb::addr_t reference_addr = valobj_extractor.GetAddress(&offset);
-            
+
             Error write_error;
             map.WritePointerToMemory(load_addr, reference_addr, write_error);
-            
+
             if (!write_error.Success())
             {
                 err.SetErrorStringWithFormat("couldn't write the contents of reference variable %s to memory: %s", m_variable_sp->GetName().AsCString(), write_error.AsCString());
@@ -507,7 +507,7 @@ public:
             {
                 Error write_error;
                 map.WritePointerToMemory(load_addr, addr_of_valobj, write_error);
-                
+
                 if (!write_error.Success())
                 {
                     err.SetErrorStringWithFormat("couldn't write the address of variable %s to memory: %s", m_variable_sp->GetName().AsCString(), write_error.AsCString());
@@ -524,14 +524,14 @@ public:
                     err.SetErrorStringWithFormat("couldn't get the value of %s: %s", m_variable_sp->GetName().AsCString(), extract_error.AsCString());
                     return;
                 }
-                    
+
                 if (m_temporary_allocation != LLDB_INVALID_ADDRESS)
                 {
                     err.SetErrorStringWithFormat("trying to create a temporary region for %s but one exists", m_variable_sp->GetName().AsCString());
                     return;
                 }
-                
-                if (data.GetByteSize() != m_variable_sp->GetType()->GetByteSize())
+
+                if (data.GetByteSize() < m_variable_sp->GetType()->GetByteSize())
                 {
                     if (data.GetByteSize() == 0 && m_variable_sp->LocationExpression().IsValid() == false)
                     {
@@ -539,20 +539,20 @@ public:
                     }
                     else
                     {
-                        err.SetErrorStringWithFormat("size of variable %s (%" PRIu64 ") disagrees with the ValueObject's size (%" PRIu64 ")",
+                        err.SetErrorStringWithFormat("size of variable %s (%" PRIu64 ") is larger than the ValueObject's size (%" PRIu64 ")",
                                                      m_variable_sp->GetName().AsCString(),
                                                      m_variable_sp->GetType()->GetByteSize(),
                                                      data.GetByteSize());
                     }
                     return;
                 }
-                
+
                 size_t bit_align = m_variable_sp->GetType()->GetLayoutCompilerType ().GetTypeBitAlign();
                 size_t byte_align = (bit_align + 7) / 8;
-                
+
                 if (!byte_align)
                     byte_align = 1;
-                
+
                 Error alloc_error;
                 const bool zero_memory = false;
 
@@ -562,31 +562,31 @@ public:
                                                     IRMemoryMap::eAllocationPolicyMirror,
                                                     zero_memory,
                                                     alloc_error);
-                
+
                 m_temporary_allocation_size = data.GetByteSize();
-                
+
                 m_original_data.reset(new DataBufferHeap(data.GetDataStart(), data.GetByteSize()));
-                
+
                 if (!alloc_error.Success())
                 {
                     err.SetErrorStringWithFormat("couldn't allocate a temporary region for %s: %s", m_variable_sp->GetName().AsCString(), alloc_error.AsCString());
                     return;
                 }
-                
+
                 Error write_error;
-                
+
                 map.WriteMemory(m_temporary_allocation, data.GetDataStart(), data.GetByteSize(), write_error);
-                
+
                 if (!write_error.Success())
                 {
                     err.SetErrorStringWithFormat("couldn't write to the temporary region for %s: %s", m_variable_sp->GetName().AsCString(), write_error.AsCString());
                     return;
                 }
-                
+
                 Error pointer_write_error;
-                
+
                 map.WritePointerToMemory(load_addr, m_temporary_allocation, pointer_write_error);
-                
+
                 if (!pointer_write_error.Success())
                 {
                     err.SetErrorStringWithFormat("couldn't write the address of the temporary region for %s: %s", m_variable_sp->GetName().AsCString(), pointer_write_error.AsCString());
@@ -594,7 +594,7 @@ public:
             }
         }
     }
-    
+
     void Dematerialize(lldb::StackFrameSP &frame_sp,
                        IRMemoryMap &map,
                        lldb::addr_t process_address,
@@ -611,36 +611,36 @@ public:
                         (uint64_t)load_addr,
                         m_variable_sp->GetName().AsCString());
         }
-        
+
         if (m_temporary_allocation != LLDB_INVALID_ADDRESS)
         {
             ExecutionContextScope *scope = frame_sp.get();
-            
+
             if (!scope)
                 scope = map.GetBestExecutionContextScope();
-            
+
             lldb::ValueObjectSP valobj_sp = ValueObjectVariable::Create(scope, m_variable_sp);
-            
+
             if (!valobj_sp)
             {
                 err.SetErrorStringWithFormat("couldn't get a value object for variable %s", m_variable_sp->GetName().AsCString());
                 return;
             }
-            
+
             lldb_private::DataExtractor data;
-            
+
             Error extract_error;
-            
+
             map.GetMemoryData(data, m_temporary_allocation, valobj_sp->GetByteSize(), extract_error);
-            
+
             if (!extract_error.Success())
             {
                 err.SetErrorStringWithFormat("couldn't get the data for variable %s", m_variable_sp->GetName().AsCString());
                 return;
             }
-            
+
             bool actually_write = true;
-            
+
             if (m_original_data)
             {
                 if ((data.GetByteSize() == m_original_data->GetByteSize()) &&
@@ -649,54 +649,54 @@ public:
                     actually_write = false;
                 }
             }
-            
+
             Error set_error;
-            
+
             if (actually_write)
             {
                 valobj_sp->SetData(data, set_error);
-                
+
                 if (!set_error.Success())
                 {
                     err.SetErrorStringWithFormat("couldn't write the new contents of %s back into the variable", m_variable_sp->GetName().AsCString());
                     return;
                 }
             }
-            
+
             Error free_error;
-            
+
             map.Free(m_temporary_allocation, free_error);
-            
+
             if (!free_error.Success())
             {
                 err.SetErrorStringWithFormat("couldn't free the temporary region for %s: %s", m_variable_sp->GetName().AsCString(), free_error.AsCString());
                 return;
             }
-            
+
             m_original_data.reset();
             m_temporary_allocation = LLDB_INVALID_ADDRESS;
             m_temporary_allocation_size = 0;
         }
     }
-    
+
     void DumpToLog(IRMemoryMap &map, lldb::addr_t process_address, Log *log) override
     {
         StreamString dump_stream;
 
         const lldb::addr_t load_addr = process_address + m_offset;
         dump_stream.Printf("0x%" PRIx64 ": EntityVariable\n", load_addr);
-        
+
         Error err;
-                
+
         lldb::addr_t ptr = LLDB_INVALID_ADDRESS;
-        
+
         {
             dump_stream.Printf("Pointer:\n");
-            
+
             DataBufferHeap data (m_size, 0);
-            
+
             map.ReadMemory(data.GetBytes(), load_addr, m_size, err);
-            
+
             if (!err.Success())
             {
                 dump_stream.Printf("  <could not be read>\n");
@@ -704,17 +704,17 @@ public:
             else
             {
                 DataExtractor extractor (data.GetBytes(), data.GetByteSize(), map.GetByteOrder(), map.GetAddressByteSize());
-                
+
                 extractor.DumpHexBytes(&dump_stream, data.GetBytes(), data.GetByteSize(), 16, load_addr);
-                
+
                 lldb::offset_t offset;
-                
+
                 ptr = extractor.GetPointer(&offset);
-                
+
                 dump_stream.PutChar('\n');
             }
         }
-        
+
         if (m_temporary_allocation == LLDB_INVALID_ADDRESS)
         {
             dump_stream.Printf("Points to process memory:\n");
@@ -723,7 +723,7 @@ public:
         {
             dump_stream.Printf("Temporary allocation:\n");
         }
-        
+
         if (ptr == LLDB_INVALID_ADDRESS)
         {
             dump_stream.Printf("  <could not be be found>\n");
@@ -731,9 +731,9 @@ public:
         else
         {
             DataBufferHeap data (m_temporary_allocation_size, 0);
-            
+
             map.ReadMemory(data.GetBytes(), m_temporary_allocation, m_temporary_allocation_size, err);
-            
+
             if (!err.Success())
             {
                 dump_stream.Printf("  <could not be read>\n");
@@ -741,24 +741,24 @@ public:
             else
             {
                 DataExtractor extractor (data.GetBytes(), data.GetByteSize(), map.GetByteOrder(), map.GetAddressByteSize());
-                
+
                 extractor.DumpHexBytes(&dump_stream, data.GetBytes(), data.GetByteSize(), 16, load_addr);
-                
+
                 dump_stream.PutChar('\n');
             }
         }
-        
+
         log->PutCString(dump_stream.GetData());
     }
-    
+
     void Wipe(IRMemoryMap &map, lldb::addr_t process_address) override
     {
         if (m_temporary_allocation != LLDB_INVALID_ADDRESS)
         {
             Error free_error;
-            
+
             map.Free(m_temporary_allocation, free_error);
-            
+
             m_temporary_allocation = LLDB_INVALID_ADDRESS;
             m_temporary_allocation_size = 0;
         }
@@ -802,7 +802,7 @@ public:
         m_size = 8;
         m_alignment = 8;
     }
-    
+
     void Materialize(lldb::StackFrameSP &frame_sp,
                      IRMemoryMap &map,
                      lldb::addr_t process_address,
@@ -815,16 +815,16 @@ public:
                 err.SetErrorString("Trying to create a temporary region for the result but one exists");
                 return;
             }
-            
+
             const lldb::addr_t load_addr = process_address + m_offset;
 
             size_t byte_size = m_type.GetByteSize(nullptr);
             size_t bit_align = m_type.GetTypeBitAlign();
             size_t byte_align = (bit_align + 7) / 8;
-            
+
             if (!byte_align)
                 byte_align = 1;
-            
+
             Error alloc_error;
             const bool zero_memory = true;
 
@@ -835,24 +835,24 @@ public:
                                                 zero_memory,
                                                 alloc_error);
             m_temporary_allocation_size = byte_size;
-            
+
             if (!alloc_error.Success())
             {
                 err.SetErrorStringWithFormat("couldn't allocate a temporary region for the result: %s", alloc_error.AsCString());
                 return;
             }
-                        
+
             Error pointer_write_error;
-            
+
             map.WritePointerToMemory(load_addr, m_temporary_allocation, pointer_write_error);
-            
+
             if (!pointer_write_error.Success())
             {
                 err.SetErrorStringWithFormat("couldn't write the address of the temporary region for the result: %s", pointer_write_error.AsCString());
             }
         }
     }
-    
+
     void Dematerialize(lldb::StackFrameSP &frame_sp,
                        IRMemoryMap &map,
                        lldb::addr_t process_address,
@@ -861,73 +861,73 @@ public:
                        Error &err) override
     {
         err.Clear();
-        
+
         ExecutionContextScope *exe_scope = map.GetBestExecutionContextScope();
-        
+
         if (!exe_scope)
         {
             err.SetErrorString("Couldn't dematerialize a result variable: invalid execution context scope");
             return;
         }
-        
+
         lldb::addr_t address;
         Error read_error;
         const lldb::addr_t load_addr = process_address + m_offset;
-        
+
         map.ReadPointerFromMemory (&address, load_addr, read_error);
-        
+
         if (!read_error.Success())
         {
             err.SetErrorString("Couldn't dematerialize a result variable: couldn't read its address");
             return;
         }
-        
+
         lldb::TargetSP target_sp = exe_scope->CalculateTarget();
-        
+
         if (!target_sp)
         {
             err.SetErrorString("Couldn't dematerialize a result variable: no target");
             return;
         }
-        
+
         Error type_system_error;
         TypeSystem *type_system = target_sp->GetScratchTypeSystemForLanguage(&type_system_error, m_type.GetMinimumLanguage());
-        
+
         if (!type_system)
         {
             err.SetErrorStringWithFormat("Couldn't dematerialize a result variable: couldn't get the corresponding type system: %s", type_system_error.AsCString());
             return;
         }
-        
+
         PersistentExpressionState *persistent_state = type_system->GetPersistentExpressionState();
-        
+
         if (!persistent_state)
         {
             err.SetErrorString("Couldn't dematerialize a result variable: corresponding type system doesn't handle persistent variables");
             return;
         }
-        
+
         ConstString name = m_delegate ? m_delegate->GetName() : persistent_state->GetNextPersistentVariableName();
-        
+
         lldb::ExpressionVariableSP ret = persistent_state->CreatePersistentVariable(exe_scope,
                                                                                     name,
                                                                                     m_type,
                                                                                     map.GetByteOrder(),
                                                                                     map.GetAddressByteSize());
-        
+
         if (!ret)
         {
             err.SetErrorStringWithFormat("couldn't dematerialize a result variable: failed to make persistent variable %s", name.AsCString());
             return;
         }
-        
+
         lldb::ProcessSP process_sp = map.GetBestExecutionContextScope()->CalculateProcess();
-        
+
         if (m_delegate)
         {
             m_delegate->DidDematerialize(ret);
         }
-        
+
         bool can_persist = (m_is_program_reference && process_sp && process_sp->CanJIT() && !(address >= frame_bottom && address < frame_top));
 
         if (can_persist && m_keep_in_memory)
@@ -939,24 +939,24 @@ public:
                                                             eAddressTypeLoad,
                                                             map.GetAddressByteSize());
         }
-        
+
         ret->ValueUpdated();
-        
+
         const size_t pvar_byte_size = ret->GetByteSize();
         uint8_t *pvar_data = ret->GetValueBytes();
-                
+
         map.ReadMemory(pvar_data, address, pvar_byte_size, read_error);
-        
+
         if (!read_error.Success())
         {
             err.SetErrorString("Couldn't dematerialize a result variable: couldn't read its memory");
             return;
         }
-        
+
         if (!can_persist || !m_keep_in_memory)
         {
             ret->m_flags |= ExpressionVariable::EVNeedsAllocation;
-            
+
             if (m_temporary_allocation != LLDB_INVALID_ADDRESS)
             {
                 Error free_error;
@@ -967,30 +967,30 @@ public:
         {
             ret->m_flags |= ExpressionVariable::EVIsLLDBAllocated;
         }
-        
+
         m_temporary_allocation = LLDB_INVALID_ADDRESS;
         m_temporary_allocation_size = 0;
     }
-    
+
     void DumpToLog(IRMemoryMap &map, lldb::addr_t process_address, Log *log) override
     {
         StreamString dump_stream;
-        
+
         const lldb::addr_t load_addr = process_address + m_offset;
 
         dump_stream.Printf("0x%" PRIx64 ": EntityResultVariable\n", load_addr);
-        
+
         Error err;
-        
+
         lldb::addr_t ptr = LLDB_INVALID_ADDRESS;
-        
+
         {
             dump_stream.Printf("Pointer:\n");
-            
+
             DataBufferHeap data (m_size, 0);
-            
+
             map.ReadMemory(data.GetBytes(), load_addr, m_size, err);
-            
+
             if (!err.Success())
             {
                 dump_stream.Printf("  <could not be read>\n");
@@ -998,17 +998,17 @@ public:
             else
             {
                 DataExtractor extractor (data.GetBytes(), data.GetByteSize(), map.GetByteOrder(), map.GetAddressByteSize());
-                
+
                 extractor.DumpHexBytes(&dump_stream, data.GetBytes(), data.GetByteSize(), 16, load_addr);
-                
+
                 lldb::offset_t offset;
-                
+
                 ptr = extractor.GetPointer(&offset);
-                
+
                 dump_stream.PutChar('\n');
             }
         }
-                
+
         if (m_temporary_allocation == LLDB_INVALID_ADDRESS)
         {
             dump_stream.Printf("Points to process memory:\n");
@@ -1017,7 +1017,7 @@ public:
         {
             dump_stream.Printf("Temporary allocation:\n");
         }
-        
+
         if (ptr == LLDB_INVALID_ADDRESS)
         {
             dump_stream.Printf("  <could not be be found>\n");
@@ -1025,9 +1025,9 @@ public:
         else
         {
             DataBufferHeap data (m_temporary_allocation_size, 0);
-            
+
             map.ReadMemory(data.GetBytes(), m_temporary_allocation, m_temporary_allocation_size, err);
-            
+
             if (!err.Success())
             {
                 dump_stream.Printf("  <could not be read>\n");
@@ -1035,25 +1035,25 @@ public:
             else
             {
                 DataExtractor extractor (data.GetBytes(), data.GetByteSize(), map.GetByteOrder(), map.GetAddressByteSize());
-                
+
                 extractor.DumpHexBytes(&dump_stream, data.GetBytes(), data.GetByteSize(), 16, load_addr);
-                
+
                 dump_stream.PutChar('\n');
             }
         }
-        
+
         log->PutCString(dump_stream.GetData());
     }
-    
+
     void Wipe(IRMemoryMap &map, lldb::addr_t process_address) override
     {
         if (!m_keep_in_memory && m_temporary_allocation != LLDB_INVALID_ADDRESS)
         {
             Error free_error;
-            
+
             map.Free(m_temporary_allocation, free_error);
         }
-        
+
         m_temporary_allocation = LLDB_INVALID_ADDRESS;
         m_temporary_allocation_size = 0;
     }
@@ -1062,7 +1062,7 @@ private:
     CompilerType    m_type;
     bool            m_is_program_reference;
     bool            m_keep_in_memory;
-    
+
     lldb::addr_t    m_temporary_allocation;
     size_t          m_temporary_allocation_size;
     Materializer::PersistentVariableDelegate *m_delegate;
@@ -1093,7 +1093,7 @@ public:
         m_size = 8;
         m_alignment = 8;
     }
-    
+
     void Materialize(lldb::StackFrameSP &frame_sp,
                      IRMemoryMap &map,
                      lldb::addr_t process_address,
@@ -1109,38 +1109,38 @@ public:
                         (uint64_t)load_addr,
                         m_symbol.GetName().AsCString());
         }
-        
+
         const Address sym_address = m_symbol.GetAddress();
 
         ExecutionContextScope *exe_scope = map.GetBestExecutionContextScope();
-        
+
         lldb::TargetSP target_sp;
-        
+
         if (exe_scope)
             target_sp = map.GetBestExecutionContextScope()->CalculateTarget();
-        
+
         if (!target_sp)
         {
             err.SetErrorStringWithFormat("couldn't resolve symbol %s because there is no target", m_symbol.GetName().AsCString());
             return;
         }
-        
+
         lldb::addr_t resolved_address = sym_address.GetLoadAddress(target_sp.get());
-        
+
         if (resolved_address == LLDB_INVALID_ADDRESS)
             resolved_address = sym_address.GetFileAddress();
-        
+
         Error pointer_write_error;
-        
+
         map.WritePointerToMemory(load_addr, resolved_address, pointer_write_error);
-        
+
         if (!pointer_write_error.Success())
         {
             err.SetErrorStringWithFormat("couldn't write the address of symbol %s: %s", m_symbol.GetName().AsCString(), pointer_write_error.AsCString());
             return;
         }
     }
-    
+
     void Dematerialize(lldb::StackFrameSP &frame_sp,
                        IRMemoryMap &map,
                        lldb::addr_t process_address,
@@ -1158,27 +1158,27 @@ public:
                         (uint64_t)load_addr,
                         m_symbol.GetName().AsCString());
         }
-        
+
         // no work needs to be done
     }
-    
+
     void DumpToLog(IRMemoryMap &map, lldb::addr_t process_address, Log *log) override
     {
         StreamString dump_stream;
-        
+
         Error err;
-        
+
         const lldb::addr_t load_addr = process_address + m_offset;
 
         dump_stream.Printf("0x%" PRIx64 ": EntitySymbol (%s)\n", load_addr, m_symbol.GetName().AsCString());
-        
+
         {
             dump_stream.Printf("Pointer:\n");
-            
+
             DataBufferHeap data (m_size, 0);
-            
+
             map.ReadMemory(data.GetBytes(), load_addr, m_size, err);
-            
+
             if (!err.Success())
             {
                 dump_stream.Printf("  <could not be read>\n");
@@ -1186,16 +1186,16 @@ public:
             else
             {
                 DataExtractor extractor (data.GetBytes(), data.GetByteSize(), map.GetByteOrder(), map.GetAddressByteSize());
-                
+
                 extractor.DumpHexBytes(&dump_stream, data.GetBytes(), data.GetByteSize(), 16, load_addr);
-                
+
                 dump_stream.PutChar('\n');
             }
         }
-        
+
         log->PutCString(dump_stream.GetData());
     }
-    
+
     void Wipe(IRMemoryMap &map, lldb::addr_t process_address) override
     {
     }
@@ -1225,14 +1225,14 @@ public:
         m_size = m_register_info.byte_size;
         m_alignment = m_register_info.byte_size;
     }
-    
+
     void Materialize(lldb::StackFrameSP &frame_sp,
                      IRMemoryMap &map,
                      lldb::addr_t process_address,
                      Error &err) override
     {
         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
-        
+
         const lldb::addr_t load_addr = process_address + m_offset;
 
         if (log)
@@ -1243,37 +1243,37 @@ public:
         }
 
         RegisterValue reg_value;
-        
+
         if (!frame_sp.get())
         {
             err.SetErrorStringWithFormat("couldn't materialize register %s without a stack frame", m_register_info.name);
             return;
         }
-        
+
         lldb::RegisterContextSP reg_context_sp = frame_sp->GetRegisterContext();
-        
+
         if (!reg_context_sp->ReadRegister(&m_register_info, reg_value))
         {
             err.SetErrorStringWithFormat("couldn't read the value of register %s", m_register_info.name);
             return;
         }
-        
+
         DataExtractor register_data;
-        
+
         if (!reg_value.GetData(register_data))
         {
             err.SetErrorStringWithFormat("couldn't get the data for register %s", m_register_info.name);
             return;
         }
-        
+
         if (register_data.GetByteSize() != m_register_info.byte_size)
         {
             err.SetErrorStringWithFormat("data for register %s had size %llu but we expected %llu", m_register_info.name, (unsigned long long)register_data.GetByteSize(), (unsigned long long)m_register_info.byte_size);
             return;
         }
-        
+
         m_register_contents.reset(new DataBufferHeap(register_data.GetDataStart(), register_data.GetByteSize()));
-        
+
         Error write_error;
         
         map.WriteMemory(load_addr, register_data.GetDataStart(), register_data.GetByteSize(), write_error);
@@ -1284,7 +1284,7 @@ public:
             return;
         }
     }
-    
+
     void Dematerialize(lldb::StackFrameSP &frame_sp,
                        IRMemoryMap &map,
                        lldb::addr_t process_address,
@@ -1293,7 +1293,7 @@ public:
                        Error &err) override
     {
         Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
-        
+
         const lldb::addr_t load_addr = process_address + m_offset;
 
         if (log)
@@ -1302,64 +1302,64 @@ public:
                         (uint64_t)load_addr,
                         m_register_info.name);
         }
-        
+
         Error extract_error;
-        
+
         DataExtractor register_data;
-        
+
         if (!frame_sp.get())
         {
             err.SetErrorStringWithFormat("couldn't dematerialize register %s without a stack frame", m_register_info.name);
             return;
         }
-        
+
         lldb::RegisterContextSP reg_context_sp = frame_sp->GetRegisterContext();
-        
+
         map.GetMemoryData(register_data, load_addr, m_register_info.byte_size, extract_error);
-        
+
         if (!extract_error.Success())
         {
             err.SetErrorStringWithFormat("couldn't get the data for register %s: %s", m_register_info.name, extract_error.AsCString());
             return;
         }
-        
+
         if (!memcmp(register_data.GetDataStart(), m_register_contents->GetBytes(), register_data.GetByteSize()))
         {
             // No write required, and in particular we avoid errors if the register wasn't writable
-            
+
             m_register_contents.reset();
             return;
         }
-        
+
         m_register_contents.reset();
-        
+
         RegisterValue register_value (const_cast<uint8_t*>(register_data.GetDataStart()), register_data.GetByteSize(), register_data.GetByteOrder());
-        
+
         if (!reg_context_sp->WriteRegister(&m_register_info, register_value))
         {
             err.SetErrorStringWithFormat("couldn't write the value of register %s", m_register_info.name);
             return;
         }
     }
-    
+
     void DumpToLog(IRMemoryMap &map, lldb::addr_t process_address, Log *log) override
     {
         StreamString dump_stream;
-        
+
         Error err;
-        
+
         const lldb::addr_t load_addr = process_address + m_offset;
 
-        
+
         dump_stream.Printf("0x%" PRIx64 ": EntityRegister (%s)\n", load_addr, m_register_info.name);
-        
+
         {
             dump_stream.Printf("Value:\n");
-            
+
             DataBufferHeap data (m_size, 0);
-            
+
             map.ReadMemory(data.GetBytes(), load_addr, m_size, err);
-            
+
             if (!err.Success())
             {
                 dump_stream.Printf("  <could not be read>\n");
@@ -1367,16 +1367,16 @@ public:
             else
             {
                 DataExtractor extractor (data.GetBytes(), data.GetByteSize(), map.GetByteOrder(), map.GetAddressByteSize());
-                
+
                 extractor.DumpHexBytes(&dump_stream, data.GetBytes(), data.GetByteSize(), 16, load_addr);
-                
+
                 dump_stream.PutChar('\n');
             }
         }
-        
+
         log->PutCString(dump_stream.GetData());
     }
-    
+
     void Wipe(IRMemoryMap &map, lldb::addr_t process_address) override
     {
     }
@@ -1406,7 +1406,7 @@ Materializer::Materializer () :
 Materializer::~Materializer ()
 {
     DematerializerSP dematerializer_sp = m_dematerializer_wp.lock();
-    
+
     if (dematerializer_sp)
         dematerializer_sp->Wipe();
 }
@@ -1507,7 +1507,7 @@ Materializer::Dematerializer::Wipe ()
 {
     if (!IsValid())
         return;
-    
+
     for (EntityUP &entity_up : m_materializer->m_entities)
     {
         entity_up->Wipe (*m_map, m_process_address);
diff --git a/source/Expression/REPL.cpp b/source/Expression/REPL.cpp
index 1727a13abd063..30f256002fc87 100644
--- a/source/Expression/REPL.cpp
+++ b/source/Expression/REPL.cpp
@@ -363,6 +363,7 @@ REPL::IOHandlerInputComplete (IOHandler &io_handler, std::string &code)
                                                                                   result_valobj_sp,
                                                                                   error,
                                                                                   0, // Line offset
+                                                                                  nullptr, // Fixed Expression
                                                                                   &jit_module_sp);
             
             //CommandInterpreter &ci = debugger.GetCommandInterpreter();
@@ -410,7 +411,7 @@ REPL::IOHandlerInputComplete (IOHandler &io_handler, std::string &code)
                         case lldb::eExpressionSetupError:
                         case lldb::eExpressionParseError:
                             add_to_code = false;
-                            // Fall through
+                            LLVM_FALLTHROUGH;
                         case lldb::eExpressionDiscarded:
                             error_sp->Printf("%s\n", error.AsCString());
                             break;
diff --git a/source/Expression/UserExpression.cpp b/source/Expression/UserExpression.cpp
index 70f004ba25c9e..3e2e07e9cb22c 100644
--- a/source/Expression/UserExpression.cpp
+++ b/source/Expression/UserExpression.cpp
@@ -16,18 +16,19 @@
 #include <string>
 #include <map>
 
+#include "Plugins/ExpressionParser/Clang/ClangPersistentVariables.h"
 #include "lldb/Core/ConstString.h"
 #include "lldb/Core/Log.h"
 #include "lldb/Core/Module.h"
 #include "lldb/Core/StreamFile.h"
 #include "lldb/Core/StreamString.h"
 #include "lldb/Core/ValueObjectConstResult.h"
+#include "lldb/Expression/DiagnosticManager.h"
 #include "lldb/Expression/ExpressionSourceCode.h"
 #include "lldb/Expression/IRExecutionUnit.h"
 #include "lldb/Expression/IRInterpreter.h"
 #include "lldb/Expression/Materializer.h"
 #include "lldb/Expression/UserExpression.h"
-#include "Plugins/ExpressionParser/Clang/ClangPersistentVariables.h"
 #include "lldb/Host/HostInfo.h"
 #include "lldb/Symbol/Block.h"
 #include "lldb/Symbol/Function.h"
@@ -159,6 +160,7 @@ UserExpression::Evaluate (ExecutionContext &exe_ctx,
                                lldb::ValueObjectSP &result_valobj_sp,
                                Error &error,
                                uint32_t line_offset,
+                               std::string *fixed_expression,
                                lldb::ModuleSP *jit_module_sp_ptr)
 {
     Log *log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP));
@@ -193,6 +195,11 @@ UserExpression::Evaluate (ExecutionContext &exe_ctx,
 
     if (process == NULL || !process->CanJIT())
         execution_policy = eExecutionPolicyNever;
+    
+    // We need to set the expression execution thread here, turns out parse can call functions in the process of
+    // looking up symbols, which will escape the context set by exe_ctx passed to Execute.
+    lldb::ThreadSP thread_sp = exe_ctx.GetThreadSP();
+    ThreadList::ExpressionExecutionThreadPusher execution_thread_pusher(thread_sp);
 
     const char *full_prefix = NULL;
     const char *option_prefix = options.GetPrefix();
@@ -232,8 +239,6 @@ UserExpression::Evaluate (ExecutionContext &exe_ctx,
             log->Printf ("== [UserExpression::Evaluate] Getting expression: %s ==", error.AsCString());
         return lldb::eExpressionSetupError;
     }
- 
-    StreamString error_stream;
 
     if (log)
         log->Printf("== [UserExpression::Evaluate] Parsing expression %s ==", expr_cstr);
@@ -244,23 +249,75 @@ UserExpression::Evaluate (ExecutionContext &exe_ctx,
     if (options.InvokeCancelCallback (lldb::eExpressionEvaluationParse))
     {
         error.SetErrorString ("expression interrupted by callback before parse");
-        result_valobj_sp = ValueObjectConstResult::Create (exe_ctx.GetBestExecutionContextScope(), error);
+        result_valobj_sp = ValueObjectConstResult::Create(exe_ctx.GetBestExecutionContextScope(), error);
         return lldb::eExpressionInterrupted;
     }
 
-    if (!user_expression_sp->Parse (error_stream,
-                                    exe_ctx,
-                                    execution_policy,
-                                    keep_expression_in_memory,
-                                    generate_debug_info))
+    DiagnosticManager diagnostic_manager;
+
+    bool parse_success = user_expression_sp->Parse(diagnostic_manager,
+                                                   exe_ctx,
+                                                   execution_policy,
+                                                   keep_expression_in_memory,
+                                                   generate_debug_info);
+    
+    // Calculate the fixed expression always, since we need it for errors.
+    std::string tmp_fixed_expression;
+    if (fixed_expression == nullptr)
+        fixed_expression = &tmp_fixed_expression;
+
+    const char *fixed_text = user_expression_sp->GetFixedText();
+    if (fixed_text != nullptr)
+            fixed_expression->append(fixed_text);
+    
+    // If there is a fixed expression, try to parse it:
+    if (!parse_success)
     {
         execution_results = lldb::eExpressionParseError;
-        if (error_stream.GetString().empty())
-            error.SetExpressionError (execution_results, "expression failed to parse, unknown error");
-        else
-            error.SetExpressionError (execution_results, error_stream.GetString().c_str());
+        if (fixed_expression && !fixed_expression->empty() && options.GetAutoApplyFixIts())
+        {
+            lldb::UserExpressionSP fixed_expression_sp(target->GetUserExpressionForLanguage (fixed_expression->c_str(),
+                                                                                             full_prefix,
+                                                                                             language,
+                                                                                             desired_type,
+                                                                                             options,
+                                                                                             error));
+            DiagnosticManager fixed_diagnostic_manager;
+            parse_success = fixed_expression_sp->Parse(fixed_diagnostic_manager,
+                                                       exe_ctx,
+                                                       execution_policy,
+                                                       keep_expression_in_memory,
+                                                       generate_debug_info);
+            if (parse_success)
+            {
+                diagnostic_manager.Clear();
+                user_expression_sp = fixed_expression_sp;
+            }
+            else
+            {
+                // If the fixed expression failed to parse, don't tell the user about, that won't help.
+                fixed_expression->clear();
+            }
+        }
+        
+        if (!parse_success)
+        {
+            if (!fixed_expression->empty() && target->GetEnableNotifyAboutFixIts())
+            {
+                error.SetExpressionErrorWithFormat(execution_results, "expression failed to parse, fixed expression suggested:\n  %s",
+                                                   fixed_expression->c_str());
+            }
+            else
+            {
+                if (!diagnostic_manager.Diagnostics().size())
+                    error.SetExpressionError(execution_results, "expression failed to parse, unknown error");
+                else
+                    error.SetExpressionError(execution_results, diagnostic_manager.GetString().c_str());
+            }
+        }
     }
-    else
+    
+    if (parse_success)
     {
         // If a pointer to a lldb::ModuleSP was passed in, return the JIT'ed module if one was created
         if (jit_module_sp_ptr)
@@ -274,8 +331,13 @@ UserExpression::Evaluate (ExecutionContext &exe_ctx,
             if (log)
                 log->Printf("== [UserExpression::Evaluate] Expression may not run, but is not constant ==");
 
-            if (error_stream.GetString().empty())
-                error.SetExpressionError (lldb::eExpressionSetupError, "expression needed to run but couldn't");
+            if (!diagnostic_manager.Diagnostics().size())
+                error.SetExpressionError(lldb::eExpressionSetupError, "expression needed to run but couldn't");
+        }
+        else if (execution_policy == eExecutionPolicyTopLevel)
+        {
+            error.SetError(UserExpression::kNoResult, lldb::eErrorTypeGeneric);
+            return lldb::eExpressionCompleted;
         }
         else
         {
@@ -286,31 +348,23 @@ UserExpression::Evaluate (ExecutionContext &exe_ctx,
                 return lldb::eExpressionInterrupted;
             }
 
-            error_stream.GetString().clear();
+            diagnostic_manager.Clear();
 
             if (log)
                 log->Printf("== [UserExpression::Evaluate] Executing expression ==");
 
-            execution_results = user_expression_sp->Execute (error_stream,
-                                                             exe_ctx,
-                                                             options,
-                                                             user_expression_sp,
-                                                             expr_result);
-
-            if (options.GetResultIsInternal() && expr_result && process)
-            {
-                process->GetTarget().GetPersistentExpressionStateForLanguage(language)->RemovePersistentVariable (expr_result);
-            }
+            execution_results =
+                user_expression_sp->Execute(diagnostic_manager, exe_ctx, options, user_expression_sp, expr_result);
 
             if (execution_results != lldb::eExpressionCompleted)
             {
                 if (log)
                     log->Printf("== [UserExpression::Evaluate] Execution completed abnormally ==");
 
-                if (error_stream.GetString().empty())
-                    error.SetExpressionError (execution_results, "expression failed to execute, unknown error");
+                if (!diagnostic_manager.Diagnostics().size())
+                    error.SetExpressionError(execution_results, "expression failed to execute, unknown error");
                 else
-                    error.SetExpressionError (execution_results, error_stream.GetString().c_str());
+                    error.SetExpressionError(execution_results, diagnostic_manager.GetString().c_str());
             }
             else
             {
@@ -346,3 +400,21 @@ UserExpression::Evaluate (ExecutionContext &exe_ctx,
 
     return execution_results;
 }
+
+lldb::ExpressionResults
+UserExpression::Execute(DiagnosticManager &diagnostic_manager,
+                        ExecutionContext &exe_ctx,
+                        const EvaluateExpressionOptions &options,
+                        lldb::UserExpressionSP &shared_ptr_to_me,
+                        lldb::ExpressionVariableSP &result_var)
+{
+    lldb::ExpressionResults expr_result = DoExecute(diagnostic_manager, exe_ctx, options, shared_ptr_to_me, result_var);
+    Target *target = exe_ctx.GetTargetPtr();
+    if (options.GetResultIsInternal() && result_var && target)
+    {
+        target->GetPersistentExpressionStateForLanguage(m_language)->RemovePersistentVariable (result_var);
+    }
+    return expr_result;
+}
+
+
diff --git a/source/Expression/UtilityFunction.cpp b/source/Expression/UtilityFunction.cpp
index f93e358d35dfa..2ff77f093db20 100644
--- a/source/Expression/UtilityFunction.cpp
+++ b/source/Expression/UtilityFunction.cpp
@@ -20,10 +20,11 @@
 #include "lldb/Core/Module.h"
 #include "lldb/Core/Stream.h"
 #include "lldb/Core/StreamFile.h"
-#include "lldb/Expression/FunctionCaller.h"
-#include "lldb/Expression/UtilityFunction.h"
+#include "lldb/Expression/DiagnosticManager.h"
 #include "lldb/Expression/ExpressionSourceCode.h"
+#include "lldb/Expression/FunctionCaller.h"
 #include "lldb/Expression/IRExecutionUnit.h"
+#include "lldb/Expression/UtilityFunction.h"
 #include "lldb/Host/Host.h"
 #include "lldb/Target/ExecutionContext.h"
 #include "lldb/Target/Process.h"
@@ -69,14 +70,17 @@ UtilityFunction::~UtilityFunction ()
 // FIXME: We should check that every time this is called it is called with the same return type & arguments...
 
 FunctionCaller *
-UtilityFunction::MakeFunctionCaller (const CompilerType &return_type, const ValueList &arg_value_list, Error &error)
+UtilityFunction::MakeFunctionCaller (const CompilerType &return_type, const ValueList &arg_value_list, lldb::ThreadSP thread_to_use_sp, Error &error)
 {
     if (m_caller_up)
         return m_caller_up.get();
     
     ProcessSP process_sp = m_jit_process_wp.lock();
     if (!process_sp)
+    {
+        error.SetErrorString("Can't make a function caller without a process.");
         return nullptr;
+    }
     
     Address impl_code_address;
     impl_code_address.SetOffset(StartAddress());
@@ -96,26 +100,24 @@ UtilityFunction::MakeFunctionCaller (const CompilerType &return_type, const Valu
     }
     if (m_caller_up)
     {
-        StreamString errors;
-        errors.Clear();
-        unsigned num_errors = m_caller_up->CompileFunction(errors);
+        DiagnosticManager diagnostics;
+
+        unsigned num_errors = m_caller_up->CompileFunction(thread_to_use_sp, diagnostics);
         if (num_errors)
         {
-            error.SetErrorStringWithFormat ("Error compiling %s caller function: \"%s\".",
-                                                m_function_name.c_str(),
-                                                errors.GetData());
+            error.SetErrorStringWithFormat("Error compiling %s caller function: \"%s\".", m_function_name.c_str(),
+                                           diagnostics.GetString().c_str());
             m_caller_up.reset();
             return nullptr;
         }
-        
-        errors.Clear();
+
+        diagnostics.Clear();
         ExecutionContext exe_ctx(process_sp);
-        
-        if (!m_caller_up->WriteFunctionWrapper(exe_ctx, errors))
+
+        if (!m_caller_up->WriteFunctionWrapper(exe_ctx, diagnostics))
         {
-            error.SetErrorStringWithFormat ("Error inserting caller function for %s: \"%s\".",
-                                                m_function_name.c_str(),
-                                                errors.GetData());
+            error.SetErrorStringWithFormat("Error inserting caller function for %s: \"%s\".", m_function_name.c_str(),
+                                           diagnostics.GetString().c_str());
             m_caller_up.reset();
             return nullptr;
         }