lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp

//===-- ClangExpressionDeclMap.cpp -----------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "ClangExpressionDeclMap.h"

#include "ASTDumper.h"
#include "ClangASTSource.h"
#include "ClangModulesDeclVendor.h"
#include "ClangPersistentVariables.h"

#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclarationName.h"
#include "clang/AST/Decl.h"
#include "lldb/lldb-private.h"
#include "lldb/Core/Address.h"
#include "lldb/Core/Error.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/RegisterValue.h"
#include "lldb/Core/ValueObjectConstResult.h"
#include "lldb/Core/ValueObjectVariable.h"
#include "lldb/Expression/Materializer.h"
#include "lldb/Host/Endian.h"
#include "lldb/Symbol/ClangASTContext.h"
#include "lldb/Symbol/CompilerDecl.h"
#include "lldb/Symbol/CompilerDeclContext.h"
#include "lldb/Symbol/CompileUnit.h"
#include "lldb/Symbol/Function.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Symbol/SymbolContext.h"
#include "lldb/Symbol/SymbolVendor.h"
#include "lldb/Symbol/Type.h"
#include "lldb/Symbol/TypeList.h"
#include "lldb/Symbol/Variable.h"
#include "lldb/Symbol/VariableList.h"
#include "lldb/Target/CPPLanguageRuntime.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/ObjCLanguageRuntime.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"

#include "Plugins/Language/CPlusPlus/CPlusPlusLanguage.h"

using namespace lldb;
using namespace lldb_private;
using namespace clang;

ClangExpressionDeclMap::ClangExpressionDeclMap (bool keep_result_in_memory,
                                                Materializer::PersistentVariableDelegate *result_delegate,
                                                ExecutionContext &exe_ctx) :
    ClangASTSource (exe_ctx.GetTargetSP()),
    m_found_entities (),
    m_struct_members (),
    m_keep_result_in_memory (keep_result_in_memory),
    m_result_delegate (result_delegate),
    m_parser_vars (),
    m_struct_vars ()
{
    EnableStructVars();
}

ClangExpressionDeclMap::~ClangExpressionDeclMap()
{
    // Note: The model is now that the parser's AST context and all associated
    //   data does not vanish until the expression has been executed.  This means
    //   that valuable lookup data (like namespaces) doesn't vanish, but

    DidParse();
    DisableStructVars();
}

bool
ClangExpressionDeclMap::WillParse(ExecutionContext &exe_ctx,
                                  Materializer *materializer)
{
    ClangASTMetrics::ClearLocalCounters();

    EnableParserVars();
    m_parser_vars->m_exe_ctx = exe_ctx;

    Target *target = exe_ctx.GetTargetPtr();
    if (exe_ctx.GetFramePtr())
        m_parser_vars->m_sym_ctx = exe_ctx.GetFramePtr()->GetSymbolContext(lldb::eSymbolContextEverything);
    else if (exe_ctx.GetThreadPtr() && exe_ctx.GetThreadPtr()->GetStackFrameAtIndex(0))
        m_parser_vars->m_sym_ctx = exe_ctx.GetThreadPtr()->GetStackFrameAtIndex(0)->GetSymbolContext(lldb::eSymbolContextEverything);
    else if (exe_ctx.GetProcessPtr())
    {
        m_parser_vars->m_sym_ctx.Clear(true);
        m_parser_vars->m_sym_ctx.target_sp = exe_ctx.GetTargetSP();
    }
    else if (target)
    {
        m_parser_vars->m_sym_ctx.Clear(true);
        m_parser_vars->m_sym_ctx.target_sp = exe_ctx.GetTargetSP();
    }

    if (target)
    {
        m_parser_vars->m_persistent_vars = llvm::cast<ClangPersistentVariables>(target->GetPersistentExpressionStateForLanguage(eLanguageTypeC));

        if (!target->GetScratchClangASTContext())
            return false;
    }

    m_parser_vars->m_target_info = GetTargetInfo();
    m_parser_vars->m_materializer = materializer;

    return true;
}

void
ClangExpressionDeclMap::InstallCodeGenerator (clang::ASTConsumer *code_gen)
{
    assert(m_parser_vars);
    m_parser_vars->m_code_gen = code_gen;
}

void
ClangExpressionDeclMap::DidParse()
{
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    if (log)
        ClangASTMetrics::DumpCounters(log);

    if (m_parser_vars.get())
    {
        for (size_t entity_index = 0, num_entities = m_found_entities.GetSize();
             entity_index < num_entities;
             ++entity_index)
        {
            ExpressionVariableSP var_sp(m_found_entities.GetVariableAtIndex(entity_index));
            if (var_sp)
                llvm::cast<ClangExpressionVariable>(var_sp.get())->DisableParserVars(GetParserID());
        }

        for (size_t pvar_index = 0, num_pvars = m_parser_vars->m_persistent_vars->GetSize();
             pvar_index < num_pvars;
             ++pvar_index)
        {
            ExpressionVariableSP pvar_sp(m_parser_vars->m_persistent_vars->GetVariableAtIndex(pvar_index));
            if (ClangExpressionVariable *clang_var = llvm::dyn_cast<ClangExpressionVariable>(pvar_sp.get()))
                clang_var->DisableParserVars(GetParserID());
        }

        DisableParserVars();
    }
}

// Interface for IRForTarget

ClangExpressionDeclMap::TargetInfo
ClangExpressionDeclMap::GetTargetInfo()
{
    assert (m_parser_vars.get());

    TargetInfo ret;

    ExecutionContext &exe_ctx = m_parser_vars->m_exe_ctx;

    Process *process = exe_ctx.GetProcessPtr();
    if (process)
    {
        ret.byte_order = process->GetByteOrder();
        ret.address_byte_size = process->GetAddressByteSize();
    }
    else
    {
        Target *target = exe_ctx.GetTargetPtr();
        if (target)
        {
            ret.byte_order = target->GetArchitecture().GetByteOrder();
            ret.address_byte_size = target->GetArchitecture().GetAddressByteSize();
        }
    }

    return ret;
}

bool
ClangExpressionDeclMap::AddPersistentVariable
(
    const NamedDecl *decl,
    const ConstString &name,
    TypeFromParser parser_type,
    bool is_result,
    bool is_lvalue
)
{
    assert (m_parser_vars.get());

    ClangASTContext *ast = llvm::dyn_cast_or_null<ClangASTContext>(parser_type.GetTypeSystem());
    if (ast == nullptr)
        return false;

    if (m_parser_vars->m_materializer && is_result)
    {
        Error err;

        ExecutionContext &exe_ctx = m_parser_vars->m_exe_ctx;
        Target *target = exe_ctx.GetTargetPtr();
        if (target == nullptr)
            return false;

        ClangASTContext *context(target->GetScratchClangASTContext());

        TypeFromUser user_type(m_ast_importer->DeportType(context->getASTContext(),
                                                          ast->getASTContext(),
                                                          parser_type.GetOpaqueQualType()),
                               context);
        
        uint32_t offset = m_parser_vars->m_materializer->AddResultVariable(user_type,
                                                                           is_lvalue,
                                                                           m_keep_result_in_memory,
                                                                           m_result_delegate,
                                                                           err);

        ClangExpressionVariable *var = new ClangExpressionVariable(exe_ctx.GetBestExecutionContextScope(),
                                                                   name,
                                                                   user_type,
                                                                   m_parser_vars->m_target_info.byte_order,
                                                                   m_parser_vars->m_target_info.address_byte_size);

        m_found_entities.AddNewlyConstructedVariable(var);
        
        var->EnableParserVars(GetParserID());

        ClangExpressionVariable::ParserVars *parser_vars = var->GetParserVars(GetParserID());

        parser_vars->m_named_decl = decl;
        parser_vars->m_parser_type = parser_type;

        var->EnableJITVars(GetParserID());

        ClangExpressionVariable::JITVars *jit_vars = var->GetJITVars(GetParserID());

        jit_vars->m_offset = offset;

        return true;
    }

    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
    ExecutionContext &exe_ctx = m_parser_vars->m_exe_ctx;
    Target *target = exe_ctx.GetTargetPtr();
    if (target == NULL)
        return false;

    ClangASTContext *context(target->GetScratchClangASTContext());

    TypeFromUser user_type(m_ast_importer->DeportType(context->getASTContext(),
                                                      ast->getASTContext(),
                                                      parser_type.GetOpaqueQualType()),
                           context);

    if (!user_type.GetOpaqueQualType())
    {
        if (log)
            log->Printf("Persistent variable's type wasn't copied successfully");
        return false;
    }

    if (!m_parser_vars->m_target_info.IsValid())
        return false;

    ClangExpressionVariable *var = llvm::cast<ClangExpressionVariable>(m_parser_vars->m_persistent_vars->CreatePersistentVariable (exe_ctx.GetBestExecutionContextScope (),
                                                                                                                                   name,
                                                                                                                                   user_type,
                                                                                                                                   m_parser_vars->m_target_info.byte_order,
                                                                                                                                   m_parser_vars->m_target_info.address_byte_size).get());

    if (!var)
        return false;

    var->m_frozen_sp->SetHasCompleteType();

    if (is_result)
        var->m_flags |= ClangExpressionVariable::EVNeedsFreezeDry;
    else
        var->m_flags |= ClangExpressionVariable::EVKeepInTarget; // explicitly-declared persistent variables should persist

    if (is_lvalue)
    {
        var->m_flags |= ClangExpressionVariable::EVIsProgramReference;
    }
    else
    {
        var->m_flags |= ClangExpressionVariable::EVIsLLDBAllocated;
        var->m_flags |= ClangExpressionVariable::EVNeedsAllocation;
    }

    if (m_keep_result_in_memory)
    {
        var->m_flags |= ClangExpressionVariable::EVKeepInTarget;
    }

    if (log)
        log->Printf("Created persistent variable with flags 0x%hx", var->m_flags);

    var->EnableParserVars(GetParserID());

    ClangExpressionVariable::ParserVars *parser_vars = var->GetParserVars(GetParserID());

    parser_vars->m_named_decl = decl;
    parser_vars->m_parser_type = parser_type;

    return true;
}

bool
ClangExpressionDeclMap::AddValueToStruct
(
    const NamedDecl *decl,
    const ConstString &name,
    llvm::Value *value,
    size_t size,
    lldb::offset_t alignment
)
{
    assert (m_struct_vars.get());
    assert (m_parser_vars.get());

    bool is_persistent_variable = false;

    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    m_struct_vars->m_struct_laid_out = false;

    if (ClangExpressionVariable::FindVariableInList(m_struct_members, decl, GetParserID()))
        return true;

    ClangExpressionVariable *var(ClangExpressionVariable::FindVariableInList(m_found_entities, decl, GetParserID()));

    if (!var)
    {
        var = ClangExpressionVariable::FindVariableInList(*m_parser_vars->m_persistent_vars, decl, GetParserID());
        is_persistent_variable = true;
    }

    if (!var)
        return false;

    if (log)
        log->Printf("Adding value for (NamedDecl*)%p [%s - %s] to the structure",
                    static_cast<const void*>(decl), name.GetCString(),
                    var->GetName().GetCString());

    // We know entity->m_parser_vars is valid because we used a parser variable
    // to find it

    ClangExpressionVariable::ParserVars *parser_vars = llvm::cast<ClangExpressionVariable>(var)->GetParserVars(GetParserID());

    parser_vars->m_llvm_value = value;

    if (ClangExpressionVariable::JITVars *jit_vars = llvm::cast<ClangExpressionVariable>(var)->GetJITVars(GetParserID()))
    {
        // We already laid this out; do not touch

        if (log)
            log->Printf("Already placed at 0x%llx", (unsigned long long)jit_vars->m_offset);
    }

    llvm::cast<ClangExpressionVariable>(var)->EnableJITVars(GetParserID());

    ClangExpressionVariable::JITVars *jit_vars = llvm::cast<ClangExpressionVariable>(var)->GetJITVars(GetParserID());

    jit_vars->m_alignment = alignment;
    jit_vars->m_size = size;

    m_struct_members.AddVariable(var->shared_from_this());

    if (m_parser_vars->m_materializer)
    {
        uint32_t offset = 0;

        Error err;

        if (is_persistent_variable)
        {
            ExpressionVariableSP var_sp(var->shared_from_this());
            offset = m_parser_vars->m_materializer->AddPersistentVariable(var_sp, nullptr, err);
        }
        else
        {
            if (const lldb_private::Symbol *sym = parser_vars->m_lldb_sym)
                offset = m_parser_vars->m_materializer->AddSymbol(*sym, err);
            else if (const RegisterInfo *reg_info = var->GetRegisterInfo())
                offset = m_parser_vars->m_materializer->AddRegister(*reg_info, err);
            else if (parser_vars->m_lldb_var)
                offset = m_parser_vars->m_materializer->AddVariable(parser_vars->m_lldb_var, err);
        }

        if (!err.Success())
            return false;

        if (log)
            log->Printf("Placed at 0x%llx", (unsigned long long)offset);

        jit_vars->m_offset = offset; // TODO DoStructLayout() should not change this.
    }

    return true;
}

bool
ClangExpressionDeclMap::DoStructLayout ()
{
    assert (m_struct_vars.get());

    if (m_struct_vars->m_struct_laid_out)
        return true;

    if (!m_parser_vars->m_materializer)
        return false;

    m_struct_vars->m_struct_alignment = m_parser_vars->m_materializer->GetStructAlignment();
    m_struct_vars->m_struct_size = m_parser_vars->m_materializer->GetStructByteSize();
    m_struct_vars->m_struct_laid_out = true;
    return true;
}

bool ClangExpressionDeclMap::GetStructInfo
(
    uint32_t &num_elements,
    size_t &size,
    lldb::offset_t &alignment
)
{
    assert (m_struct_vars.get());

    if (!m_struct_vars->m_struct_laid_out)
        return false;

    num_elements = m_struct_members.GetSize();
    size = m_struct_vars->m_struct_size;
    alignment = m_struct_vars->m_struct_alignment;

    return true;
}

bool
ClangExpressionDeclMap::GetStructElement
(
    const NamedDecl *&decl,
    llvm::Value *&value,
    lldb::offset_t &offset,
    ConstString &name,
    uint32_t index
)
{
    assert (m_struct_vars.get());

    if (!m_struct_vars->m_struct_laid_out)
        return false;

    if (index >= m_struct_members.GetSize())
        return false;

    ExpressionVariableSP member_sp(m_struct_members.GetVariableAtIndex(index));

    if (!member_sp)
        return false;

    ClangExpressionVariable::ParserVars *parser_vars = llvm::cast<ClangExpressionVariable>(member_sp.get())->GetParserVars(GetParserID());
    ClangExpressionVariable::JITVars *jit_vars = llvm::cast<ClangExpressionVariable>(member_sp.get())->GetJITVars(GetParserID());

    if (!parser_vars ||
        !jit_vars ||
        !member_sp->GetValueObject())
        return false;

    decl = parser_vars->m_named_decl;
    value = parser_vars->m_llvm_value;
    offset = jit_vars->m_offset;
    name = member_sp->GetName();

    return true;
}

bool
ClangExpressionDeclMap::GetFunctionInfo
(
    const NamedDecl *decl,
    uint64_t &ptr
)
{
    ClangExpressionVariable *entity(ClangExpressionVariable::FindVariableInList(m_found_entities, decl, GetParserID()));

    if (!entity)
        return false;

    // We know m_parser_vars is valid since we searched for the variable by
    // its NamedDecl

    ClangExpressionVariable::ParserVars *parser_vars = entity->GetParserVars(GetParserID());

    ptr = parser_vars->m_lldb_value.GetScalar().ULongLong();

    return true;
}

static void
FindCodeSymbolInContext
(
    const ConstString &name,
    SymbolContext &sym_ctx,
    uint32_t name_type_mask,
    SymbolContextList &sc_list
)
{
    sc_list.Clear();
    SymbolContextList temp_sc_list;
    if (sym_ctx.module_sp)
        sym_ctx.module_sp->FindFunctions(name,
                                         NULL,
                                         name_type_mask,
                                         true,  // include_symbols
                                         false, // include_inlines
                                         true,  // append
                                         temp_sc_list);
    if (temp_sc_list.GetSize() == 0)
    {
        if (sym_ctx.target_sp)
            sym_ctx.target_sp->GetImages().FindFunctions(name,
                                                         name_type_mask,
                                                         true,  // include_symbols
                                                         false, // include_inlines
                                                         true,  // append
                                                         temp_sc_list);
    }

    SymbolContextList internal_symbol_sc_list;
    unsigned temp_sc_list_size = temp_sc_list.GetSize();
    for (unsigned i = 0; i < temp_sc_list_size; i++)
    {
        SymbolContext sc;
        temp_sc_list.GetContextAtIndex(i, sc);
        if (sc.function)
        {
            sc_list.Append(sc);
        }
        else if (sc.symbol)
        {
            if (sc.symbol->IsExternal())
            {
                sc_list.Append(sc);
            }
            else
            {
                internal_symbol_sc_list.Append(sc);
            }
        }
    }

    // If we had internal symbols and we didn't find any external symbols or
    // functions in debug info, then fallback to the internal symbols
    if (sc_list.GetSize() == 0 && internal_symbol_sc_list.GetSize())
    {
        sc_list = internal_symbol_sc_list;
    }
}

bool
ClangExpressionDeclMap::GetFunctionAddress
(
    const ConstString &name,
    uint64_t &func_addr
)
{
    assert (m_parser_vars.get());

    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
    ExecutionContext &exe_ctx = m_parser_vars->m_exe_ctx;
    Target *target = exe_ctx.GetTargetPtr();
    // Back out in all cases where we're not fully initialized
    if (target == NULL)
        return false;
    if (!m_parser_vars->m_sym_ctx.target_sp)
        return false;

    SymbolContextList sc_list;

    FindCodeSymbolInContext(name, m_parser_vars->m_sym_ctx, eFunctionNameTypeAuto, sc_list);

    uint32_t sc_list_size = sc_list.GetSize();

    if (sc_list_size == 0)
    {
        SymbolContext &sc = m_parser_vars->m_sym_ctx;
        if (sc.comp_unit)
        {
            LanguageType lang_type = sc.comp_unit->GetLanguage();
            if (Language::LanguageIsCPlusPlus(lang_type) &&
                CPlusPlusLanguage::IsCPPMangledName(name.AsCString()))
            {
                // 1. Demangle the name
                Mangled mangled(name, true);
                ConstString demangled = mangled.GetDemangledName(lang_type);

                if (demangled)
                {
                    FindCodeSymbolInContext(
                        demangled, m_parser_vars->m_sym_ctx, eFunctionNameTypeFull, sc_list);
                    sc_list_size = sc_list.GetSize();
                }
            }
        }
    }

    if (sc_list_size == 0)
    {
        // We occasionally get debug information in which a const function is reported
        // as non-const, so the mangled name is wrong.  This is a hack to compensate.

        if (!strncmp(name.GetCString(), "_ZN", 3) &&
            strncmp(name.GetCString(), "_ZNK", 4))
        {
            std::string fixed_scratch("_ZNK");
            fixed_scratch.append(name.GetCString() + 3);
            ConstString fixed_name(fixed_scratch.c_str());

            if (log)
                log->Printf("Failed to find symbols given non-const name %s; trying %s", name.GetCString(), fixed_name.GetCString());

            FindCodeSymbolInContext(
                fixed_name, m_parser_vars->m_sym_ctx, eFunctionNameTypeAuto, sc_list);
            sc_list_size = sc_list.GetSize();
        }
    }

    lldb::addr_t intern_callable_load_addr = LLDB_INVALID_ADDRESS;

    for (uint32_t i=0; i<sc_list_size; ++i)
    {
        SymbolContext sym_ctx;
        sc_list.GetContextAtIndex(i, sym_ctx);


        lldb::addr_t callable_load_addr = LLDB_INVALID_ADDRESS;

        if (sym_ctx.function)
        {
            const Address func_so_addr = sym_ctx.function->GetAddressRange().GetBaseAddress();
            if (func_so_addr.IsValid())
            {
                callable_load_addr = func_so_addr.GetCallableLoadAddress(target, false);
            }
        }
        else if (sym_ctx.symbol)
        {
            if (sym_ctx.symbol->IsExternal())
                callable_load_addr = sym_ctx.symbol->ResolveCallableAddress(*target);
            else
            {
                if (intern_callable_load_addr == LLDB_INVALID_ADDRESS)
                    intern_callable_load_addr = sym_ctx.symbol->ResolveCallableAddress(*target);
            }
        }

        if (callable_load_addr != LLDB_INVALID_ADDRESS)
        {
            func_addr = callable_load_addr;
            return true;
        }
    }

    // See if we found an internal symbol
    if (intern_callable_load_addr != LLDB_INVALID_ADDRESS)
    {
        func_addr = intern_callable_load_addr;
        return true;
    }

    return false;
}

addr_t
ClangExpressionDeclMap::GetSymbolAddress (Target &target,
                                          Process *process,
                                          const ConstString &name,
                                          lldb::SymbolType symbol_type,
                                          lldb_private::Module *module)
{
    SymbolContextList sc_list;

    if (module)
        module->FindSymbolsWithNameAndType(name, symbol_type, sc_list);
    else
        target.GetImages().FindSymbolsWithNameAndType(name, symbol_type, sc_list);

    const uint32_t num_matches = sc_list.GetSize();
    addr_t symbol_load_addr = LLDB_INVALID_ADDRESS;

    for (uint32_t i=0; i<num_matches && (symbol_load_addr == 0 || symbol_load_addr == LLDB_INVALID_ADDRESS); i++)
    {
        SymbolContext sym_ctx;
        sc_list.GetContextAtIndex(i, sym_ctx);

        const Address sym_address = sym_ctx.symbol->GetAddress();

        if (!sym_address.IsValid())
            continue;

        switch (sym_ctx.symbol->GetType())
        {
            case eSymbolTypeCode:
            case eSymbolTypeTrampoline:
                symbol_load_addr = sym_address.GetCallableLoadAddress (&target);
                break;

            case eSymbolTypeResolver:
                symbol_load_addr = sym_address.GetCallableLoadAddress (&target, true);
                break;

            case eSymbolTypeReExported:
                {
                    ConstString reexport_name = sym_ctx.symbol->GetReExportedSymbolName();
                    if (reexport_name)
                    {
                        ModuleSP reexport_module_sp;
                        ModuleSpec reexport_module_spec;
                        reexport_module_spec.GetPlatformFileSpec() = sym_ctx.symbol->GetReExportedSymbolSharedLibrary();
                        if (reexport_module_spec.GetPlatformFileSpec())
                        {
                            reexport_module_sp = target.GetImages().FindFirstModule(reexport_module_spec);
                            if (!reexport_module_sp)
                            {
                                reexport_module_spec.GetPlatformFileSpec().GetDirectory().Clear();
                                reexport_module_sp = target.GetImages().FindFirstModule(reexport_module_spec);
                            }
                        }
                        symbol_load_addr = GetSymbolAddress(target, process, sym_ctx.symbol->GetReExportedSymbolName(), symbol_type, reexport_module_sp.get());
                    }
                }
                break;

            case eSymbolTypeData:
            case eSymbolTypeRuntime:
            case eSymbolTypeVariable:
            case eSymbolTypeLocal:
            case eSymbolTypeParam:
            case eSymbolTypeInvalid:
            case eSymbolTypeAbsolute:
            case eSymbolTypeException:
            case eSymbolTypeSourceFile:
            case eSymbolTypeHeaderFile:
            case eSymbolTypeObjectFile:
            case eSymbolTypeCommonBlock:
            case eSymbolTypeBlock:
            case eSymbolTypeVariableType:
            case eSymbolTypeLineEntry:
            case eSymbolTypeLineHeader:
            case eSymbolTypeScopeBegin:
            case eSymbolTypeScopeEnd:
            case eSymbolTypeAdditional:
            case eSymbolTypeCompiler:
            case eSymbolTypeInstrumentation:
            case eSymbolTypeUndefined:
            case eSymbolTypeObjCClass:
            case eSymbolTypeObjCMetaClass:
            case eSymbolTypeObjCIVar:
                symbol_load_addr = sym_address.GetLoadAddress (&target);
                break;
        }
    }

    if (symbol_load_addr == LLDB_INVALID_ADDRESS && process)
    {
        ObjCLanguageRuntime *runtime = process->GetObjCLanguageRuntime();

        if (runtime)
        {
            symbol_load_addr = runtime->LookupRuntimeSymbol(name);
        }
    }

    return symbol_load_addr;
}

addr_t
ClangExpressionDeclMap::GetSymbolAddress (const ConstString &name, lldb::SymbolType symbol_type)
{
    assert (m_parser_vars.get());

    if (!m_parser_vars->m_exe_ctx.GetTargetPtr())
        return false;

    return GetSymbolAddress(m_parser_vars->m_exe_ctx.GetTargetRef(), m_parser_vars->m_exe_ctx.GetProcessPtr(), name, symbol_type);
}

const Symbol *
ClangExpressionDeclMap::FindGlobalDataSymbol (Target &target,
                                              const ConstString &name,
                                              lldb_private::Module *module)
{
    SymbolContextList sc_list;

    if (module)
        module->FindSymbolsWithNameAndType(name, eSymbolTypeAny, sc_list);
    else
        target.GetImages().FindSymbolsWithNameAndType(name, eSymbolTypeAny, sc_list);

    const uint32_t matches = sc_list.GetSize();
    for (uint32_t i=0; i<matches; ++i)
    {
        SymbolContext sym_ctx;
        sc_list.GetContextAtIndex(i, sym_ctx);
        if (sym_ctx.symbol)
        {
            const Symbol *symbol = sym_ctx.symbol;
            const Address sym_address = symbol->GetAddress();

            if (sym_address.IsValid())
            {
                switch (symbol->GetType())
                {
                    case eSymbolTypeData:
                    case eSymbolTypeRuntime:
                    case eSymbolTypeAbsolute:
                    case eSymbolTypeObjCClass:
                    case eSymbolTypeObjCMetaClass:
                    case eSymbolTypeObjCIVar:
                        if (symbol->GetDemangledNameIsSynthesized())
                        {
                            // If the demangled name was synthesized, then don't use it
                            // for expressions. Only let the symbol match if the mangled
                            // named matches for these symbols.
                            if (symbol->GetMangled().GetMangledName() != name)
                                break;
                        }
                        return symbol;

                    case eSymbolTypeReExported:
                        {
                            ConstString reexport_name = symbol->GetReExportedSymbolName();
                            if (reexport_name)
                            {
                                ModuleSP reexport_module_sp;
                                ModuleSpec reexport_module_spec;
                                reexport_module_spec.GetPlatformFileSpec() = symbol->GetReExportedSymbolSharedLibrary();
                                if (reexport_module_spec.GetPlatformFileSpec())
                                {
                                    reexport_module_sp = target.GetImages().FindFirstModule(reexport_module_spec);
                                    if (!reexport_module_sp)
                                    {
                                        reexport_module_spec.GetPlatformFileSpec().GetDirectory().Clear();
                                        reexport_module_sp = target.GetImages().FindFirstModule(reexport_module_spec);
                                    }
                                }
                                // Don't allow us to try and resolve a re-exported symbol if it is the same
                                // as the current symbol
                                if (name == symbol->GetReExportedSymbolName() && module == reexport_module_sp.get())
                                    return NULL;

                                return FindGlobalDataSymbol(target, symbol->GetReExportedSymbolName(), reexport_module_sp.get());
                            }
                        }
                        break;

                    case eSymbolTypeCode: // We already lookup functions elsewhere
                    case eSymbolTypeVariable:
                    case eSymbolTypeLocal:
                    case eSymbolTypeParam:
                    case eSymbolTypeTrampoline:
                    case eSymbolTypeInvalid:
                    case eSymbolTypeException:
                    case eSymbolTypeSourceFile:
                    case eSymbolTypeHeaderFile:
                    case eSymbolTypeObjectFile:
                    case eSymbolTypeCommonBlock:
                    case eSymbolTypeBlock:
                    case eSymbolTypeVariableType:
                    case eSymbolTypeLineEntry:
                    case eSymbolTypeLineHeader:
                    case eSymbolTypeScopeBegin:
                    case eSymbolTypeScopeEnd:
                    case eSymbolTypeAdditional:
                    case eSymbolTypeCompiler:
                    case eSymbolTypeInstrumentation:
                    case eSymbolTypeUndefined:
                    case eSymbolTypeResolver:
                        break;
                }
            }
        }
    }

    return NULL;
}

lldb::VariableSP
ClangExpressionDeclMap::FindGlobalVariable
(
    Target &target,
    ModuleSP &module,
    const ConstString &name,
    CompilerDeclContext *namespace_decl,
    TypeFromUser *type
)
{
    VariableList vars;

    if (module && namespace_decl)
        module->FindGlobalVariables (name, namespace_decl, true, -1, vars);
    else
        target.GetImages().FindGlobalVariables(name, true, -1, vars);

    if (vars.GetSize())
    {
        if (type)
        {
            for (size_t i = 0; i < vars.GetSize(); ++i)
            {
                VariableSP var_sp = vars.GetVariableAtIndex(i);

                if (ClangASTContext::AreTypesSame(*type, var_sp->GetType()->GetFullCompilerType ()))
                    return var_sp;
            }
        }
        else
        {
            return vars.GetVariableAtIndex(0);
        }
    }

    return VariableSP();
}

// Interface for ClangASTSource

void
ClangExpressionDeclMap::FindExternalVisibleDecls (NameSearchContext &context)
{
    assert (m_ast_context);

    ClangASTMetrics::RegisterVisibleQuery();

    const ConstString name(context.m_decl_name.getAsString().c_str());

    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    if (GetImportInProgress())
    {
        if (log && log->GetVerbose())
            log->Printf("Ignoring a query during an import");
        return;
    }

    static unsigned int invocation_id = 0;
    unsigned int current_id = invocation_id++;

    if (log)
    {
        if (!context.m_decl_context)
            log->Printf("ClangExpressionDeclMap::FindExternalVisibleDecls[%u] for '%s' in a NULL DeclContext", current_id, name.GetCString());
        else if (const NamedDecl *context_named_decl = dyn_cast<NamedDecl>(context.m_decl_context))
            log->Printf("ClangExpressionDeclMap::FindExternalVisibleDecls[%u] for '%s' in '%s'", current_id, name.GetCString(), context_named_decl->getNameAsString().c_str());
        else
            log->Printf("ClangExpressionDeclMap::FindExternalVisibleDecls[%u] for '%s' in a '%s'", current_id, name.GetCString(), context.m_decl_context->getDeclKindName());
    }

    if (const NamespaceDecl *namespace_context = dyn_cast<NamespaceDecl>(context.m_decl_context))
    {
        ClangASTImporter::NamespaceMapSP namespace_map = m_ast_importer->GetNamespaceMap(namespace_context);

        if (log && log->GetVerbose())
            log->Printf("  CEDM::FEVD[%u] Inspecting (NamespaceMap*)%p (%d entries)",
                        current_id, static_cast<void*>(namespace_map.get()),
                        (int)namespace_map->size());

        if (!namespace_map)
            return;

        for (ClangASTImporter::NamespaceMap::iterator i = namespace_map->begin(), e = namespace_map->end();
             i != e;
             ++i)
        {
            if (log)
                log->Printf("  CEDM::FEVD[%u] Searching namespace %s in module %s",
                            current_id,
                            i->second.GetName().AsCString(),
                            i->first->GetFileSpec().GetFilename().GetCString());

            FindExternalVisibleDecls(context,
                                     i->first,
                                     i->second,
                                     current_id);
        }
    }
    else if (isa<TranslationUnitDecl>(context.m_decl_context))
    {
        CompilerDeclContext namespace_decl;

        if (log)
            log->Printf("  CEDM::FEVD[%u] Searching the root namespace", current_id);

        FindExternalVisibleDecls(context,
                                 lldb::ModuleSP(),
                                 namespace_decl,
                                 current_id);
    }

    if (!context.m_found.variable)
        ClangASTSource::FindExternalVisibleDecls(context);
}

void
ClangExpressionDeclMap::FindExternalVisibleDecls (NameSearchContext &context,
                                                  lldb::ModuleSP module_sp,
                                                  CompilerDeclContext &namespace_decl,
                                                  unsigned int current_id)
{
    assert (m_ast_context);

    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    SymbolContextList sc_list;

    const ConstString name(context.m_decl_name.getAsString().c_str());

    const char *name_unique_cstr = name.GetCString();

    if (name_unique_cstr == NULL)
        return;

    static ConstString id_name("id");
    static ConstString Class_name("Class");

    if (name == id_name || name == Class_name)
        return;

    // Only look for functions by name out in our symbols if the function
    // doesn't start with our phony prefix of '$'
    Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();
    StackFrame *frame = m_parser_vars->m_exe_ctx.GetFramePtr();
    SymbolContext sym_ctx;
    if (frame != nullptr)
        sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction|lldb::eSymbolContextBlock);
    if (name_unique_cstr[0] == '$' && !namespace_decl)
    {
        static ConstString g_lldb_class_name ("$__lldb_class");

        if (name == g_lldb_class_name)
        {
            // Clang is looking for the type of "this"

            if (frame == NULL)
                return;


            // Find the block that defines the function represented by "sym_ctx"
            Block *function_block = sym_ctx.GetFunctionBlock();

            if (!function_block)
                return;

            CompilerDeclContext function_decl_ctx = function_block->GetDeclContext();

            if (!function_decl_ctx)
                return;

            clang::CXXMethodDecl *method_decl = ClangASTContext::DeclContextGetAsCXXMethodDecl(function_decl_ctx);

            if (method_decl)
            {
                clang::CXXRecordDecl *class_decl = method_decl->getParent();

                QualType class_qual_type(class_decl->getTypeForDecl(), 0);

                TypeFromUser class_user_type (class_qual_type.getAsOpaquePtr(),
                                              ClangASTContext::GetASTContext(&class_decl->getASTContext()));

                if (log)
                {
                    ASTDumper ast_dumper(class_qual_type);
                    log->Printf("  CEDM::FEVD[%u] Adding type for $__lldb_class: %s", current_id, ast_dumper.GetCString());
                }

                TypeFromParser class_type = CopyClassType(class_user_type, current_id);

                if (!class_type.IsValid())
                    return;

                TypeSourceInfo *type_source_info = m_ast_context->getTrivialTypeSourceInfo(QualType::getFromOpaquePtr(class_type.GetOpaqueQualType()));

                if (!type_source_info)
                    return;

                TypedefDecl *typedef_decl = TypedefDecl::Create(*m_ast_context,
                                                                m_ast_context->getTranslationUnitDecl(),
                                                                SourceLocation(),
                                                                SourceLocation(),
                                                                context.m_decl_name.getAsIdentifierInfo(),
                                                                type_source_info);


                if (!typedef_decl)
                    return;

                context.AddNamedDecl(typedef_decl);

                if (method_decl->isInstance())
                {
                    // self is a pointer to the object

                    QualType class_pointer_type = method_decl->getASTContext().getPointerType(class_qual_type);

                    TypeFromUser self_user_type(class_pointer_type.getAsOpaquePtr(),
                                                ClangASTContext::GetASTContext(&method_decl->getASTContext()));

                    m_struct_vars->m_object_pointer_type = self_user_type;
                }
            }
            else
            {
                // This branch will get hit if we are executing code in the context of a function that
                // claims to have an object pointer (through DW_AT_object_pointer?) but is not formally a
                // method of the class.  In that case, just look up the "this" variable in the current
                // scope and use its type.
                // FIXME: This code is formally correct, but clang doesn't currently emit DW_AT_object_pointer
                // for C++ so it hasn't actually been tested.

                VariableList *vars = frame->GetVariableList(false);

                lldb::VariableSP this_var = vars->FindVariable(ConstString("this"));

                if (this_var &&
                    this_var->IsInScope(frame) &&
                    this_var->LocationIsValidForFrame (frame))
                {
                    Type *this_type = this_var->GetType();

                    if (!this_type)
                        return;

                    CompilerType pointee_type = this_type->GetForwardCompilerType ().GetPointeeType();

                    if (pointee_type.IsValid())
                    {
                        if (log)
                        {
                            ASTDumper ast_dumper(this_type->GetFullCompilerType ());
                            log->Printf("  FEVD[%u] Adding type for $__lldb_objc_class: %s", current_id, ast_dumper.GetCString());
                        }

                        TypeFromUser class_user_type(pointee_type);
                        AddOneType(context, class_user_type, current_id);


                        TypeFromUser this_user_type(this_type->GetFullCompilerType ());
                        m_struct_vars->m_object_pointer_type = this_user_type;
                        return;
                    }
                }
            }

            return;
        }

        static ConstString g_lldb_objc_class_name ("$__lldb_objc_class");
        if (name == g_lldb_objc_class_name)
        {
            // Clang is looking for the type of "*self"

            if (!frame)
                return;

            SymbolContext sym_ctx = frame->GetSymbolContext(lldb::eSymbolContextFunction|lldb::eSymbolContextBlock);

            // Find the block that defines the function represented by "sym_ctx"
            Block *function_block = sym_ctx.GetFunctionBlock();

            if (!function_block)
                return;

            CompilerDeclContext function_decl_ctx = function_block->GetDeclContext();

            if (!function_decl_ctx)
                return;

            clang::ObjCMethodDecl *method_decl = ClangASTContext::DeclContextGetAsObjCMethodDecl(function_decl_ctx);

            if (method_decl)
            {
                ObjCInterfaceDecl* self_interface = method_decl->getClassInterface();

                if (!self_interface)
                    return;

                const clang::Type *interface_type = self_interface->getTypeForDecl();

                if (!interface_type)
                    return; // This is unlikely, but we have seen crashes where this occurred

                TypeFromUser class_user_type(QualType(interface_type, 0).getAsOpaquePtr(),
                                             ClangASTContext::GetASTContext(&method_decl->getASTContext()));

                if (log)
                {
                    ASTDumper ast_dumper(interface_type);
                    log->Printf("  FEVD[%u] Adding type for $__lldb_objc_class: %s", current_id, ast_dumper.GetCString());
                }

                AddOneType(context, class_user_type, current_id);

                if (method_decl->isInstanceMethod())
                {
                    // self is a pointer to the object

                    QualType class_pointer_type = method_decl->getASTContext().getObjCObjectPointerType(QualType(interface_type, 0));

                    TypeFromUser self_user_type(class_pointer_type.getAsOpaquePtr(),
                                                ClangASTContext::GetASTContext(&method_decl->getASTContext()));

                    m_struct_vars->m_object_pointer_type = self_user_type;
                }
                else
                {
                    // self is a Class pointer
                    QualType class_type = method_decl->getASTContext().getObjCClassType();

                    TypeFromUser self_user_type(class_type.getAsOpaquePtr(),
                                                ClangASTContext::GetASTContext(&method_decl->getASTContext()));

                    m_struct_vars->m_object_pointer_type = self_user_type;
                }

                return;
            }
            else
            {
                // This branch will get hit if we are executing code in the context of a function that
                // claims to have an object pointer (through DW_AT_object_pointer?) but is not formally a
                // method of the class.  In that case, just look up the "self" variable in the current
                // scope and use its type.

                VariableList *vars = frame->GetVariableList(false);

                lldb::VariableSP self_var = vars->FindVariable(ConstString("self"));

                if (self_var &&
                    self_var->IsInScope(frame) &&
                    self_var->LocationIsValidForFrame (frame))
                {
                    Type *self_type = self_var->GetType();

                    if (!self_type)
                        return;

                    CompilerType self_clang_type = self_type->GetFullCompilerType ();

                    if (ClangASTContext::IsObjCClassType(self_clang_type))
                    {
                        return;
                    }
                    else if (ClangASTContext::IsObjCObjectPointerType(self_clang_type))
                    {
                        self_clang_type = self_clang_type.GetPointeeType();

                        if (!self_clang_type)
                            return;

                        if (log)
                        {
                            ASTDumper ast_dumper(self_type->GetFullCompilerType ());
                            log->Printf("  FEVD[%u] Adding type for $__lldb_objc_class: %s", current_id, ast_dumper.GetCString());
                        }

                        TypeFromUser class_user_type (self_clang_type);

                        AddOneType(context, class_user_type, current_id);

                        TypeFromUser self_user_type(self_type->GetFullCompilerType ());

                        m_struct_vars->m_object_pointer_type = self_user_type;
                        return;
                    }
                }
            }

            return;
        }

        // any other $__lldb names should be weeded out now
        if (!::strncmp(name_unique_cstr, "$__lldb", sizeof("$__lldb") - 1))
            return;

        do
        {
            if (!target)
                break;

            ClangASTContext *scratch_clang_ast_context = target->GetScratchClangASTContext();

            if (!scratch_clang_ast_context)
                break;

            ASTContext *scratch_ast_context = scratch_clang_ast_context->getASTContext();

            if (!scratch_ast_context)
                break;

            TypeDecl *ptype_type_decl = m_parser_vars->m_persistent_vars->GetPersistentType(name);

            if (!ptype_type_decl)
                break;

            Decl *parser_ptype_decl = m_ast_importer->CopyDecl(m_ast_context, scratch_ast_context, ptype_type_decl);

            if (!parser_ptype_decl)
                break;

            TypeDecl *parser_ptype_type_decl = dyn_cast<TypeDecl>(parser_ptype_decl);

            if (!parser_ptype_type_decl)
                break;

            if (log)
                log->Printf("  CEDM::FEVD[%u] Found persistent type %s", current_id, name.GetCString());

            context.AddNamedDecl(parser_ptype_type_decl);
        } while (0);

        ExpressionVariableSP pvar_sp(m_parser_vars->m_persistent_vars->GetVariable(name));

        if (pvar_sp)
        {
            AddOneVariable(context, pvar_sp, current_id);
            return;
        }

        const char *reg_name(&name.GetCString()[1]);

        if (m_parser_vars->m_exe_ctx.GetRegisterContext())
        {
            const RegisterInfo *reg_info(m_parser_vars->m_exe_ctx.GetRegisterContext()->GetRegisterInfoByName(reg_name));

            if (reg_info)
            {
                if (log)
                    log->Printf("  CEDM::FEVD[%u] Found register %s", current_id, reg_info->name);

                AddOneRegister(context, reg_info, current_id);
            }
        }
    }
    else
    {
        ValueObjectSP valobj;
        VariableSP var;

        if (frame && !namespace_decl)
        {
            CompilerDeclContext compiler_decl_context = sym_ctx.block != nullptr ? sym_ctx.block->GetDeclContext() : CompilerDeclContext();

            if (compiler_decl_context)
            {
                // Make sure that the variables are parsed so that we have the declarations
                VariableListSP vars = frame->GetInScopeVariableList(true);
                for (size_t i = 0; i < vars->GetSize(); i++)
                    vars->GetVariableAtIndex(i)->GetDecl();

                // Search for declarations matching the name
                std::vector<CompilerDecl> found_decls = compiler_decl_context.FindDeclByName(name);
                
                bool variable_found = false;
                for (CompilerDecl decl : found_decls)
                {
                    var = decl.GetAsVariable();
                    if (var)
                    {
                        variable_found = true;
                        valobj = ValueObjectVariable::Create(frame, var);
                        AddOneVariable(context, var, valobj, current_id);
                        context.m_found.variable = true;
                    }
                }
                if (variable_found)
                    return;
            }
        }
        if (target)
        {
            var = FindGlobalVariable (*target,
                                      module_sp,
                                      name,
                                      &namespace_decl,
                                      NULL);

            if (var)
            {
                valobj = ValueObjectVariable::Create(target, var);
                AddOneVariable(context, var, valobj, current_id);
                context.m_found.variable = true;
                return;
            }
        }
        
        std::vector<clang::NamedDecl *> decls_from_modules;
        
        if (target)
        {
            if (ClangModulesDeclVendor *decl_vendor = target->GetClangModulesDeclVendor())
            {
                decl_vendor->FindDecls(name, false, UINT32_MAX, decls_from_modules);
            }
        }

        if (!context.m_found.variable)
        {
            const bool include_inlines = false;
            const bool append = false;

            if (namespace_decl && module_sp)
            {
                const bool include_symbols = false;

                module_sp->FindFunctions(name,
                                         &namespace_decl,
                                         eFunctionNameTypeBase,
                                         include_symbols,
                                         include_inlines,
                                         append,
                                         sc_list);
            }
            else if (target && !namespace_decl)
            {
                const bool include_symbols = true;

                // TODO Fix FindFunctions so that it doesn't return
                //   instance methods for eFunctionNameTypeBase.

                target->GetImages().FindFunctions(name,
                                                  eFunctionNameTypeFull,
                                                  include_symbols,
                                                  include_inlines,
                                                  append,
                                                  sc_list);
            }

            if (sc_list.GetSize())
            {
                Symbol *extern_symbol = NULL;
                Symbol *non_extern_symbol = NULL;

                for (uint32_t index = 0, num_indices = sc_list.GetSize();
                     index < num_indices;
                     ++index)
                {
                    SymbolContext sym_ctx;
                    sc_list.GetContextAtIndex(index, sym_ctx);

                    if (sym_ctx.function)
                    {
                        CompilerDeclContext decl_ctx = sym_ctx.function->GetDeclContext();

                        if (!decl_ctx)
                            continue;

                        // Filter out class/instance methods.
                        if (decl_ctx.IsClassMethod(nullptr, nullptr, nullptr))
                            continue;

                        AddOneFunction(context, sym_ctx.function, NULL, current_id);
                        context.m_found.function_with_type_info = true;
                        context.m_found.function = true;
                    }
                    else if (sym_ctx.symbol)
                    {
                        if (sym_ctx.symbol->GetType() == eSymbolTypeReExported && target)
                        {
                            sym_ctx.symbol = sym_ctx.symbol->ResolveReExportedSymbol(*target);
                            if (sym_ctx.symbol == NULL)
                                continue;
                        }

                        if (sym_ctx.symbol->IsExternal())
                            extern_symbol = sym_ctx.symbol;
                        else
                            non_extern_symbol = sym_ctx.symbol;
                    }
                }
                
                if (!context.m_found.function_with_type_info)
                {
                    for (clang::NamedDecl *decl : decls_from_modules)
                    {
                        if (llvm::isa<clang::FunctionDecl>(decl))
                        {
                            clang::NamedDecl *copied_decl = llvm::cast<FunctionDecl>(m_ast_importer->CopyDecl(m_ast_context, &decl->getASTContext(), decl));
                            context.AddNamedDecl(copied_decl);
                            context.m_found.function_with_type_info = true;
                        }
                    }
                }

                if (!context.m_found.function_with_type_info)
                {
                    if (extern_symbol)
                    {
                        AddOneFunction (context, NULL, extern_symbol, current_id);
                        context.m_found.function = true;
                    }
                    else if (non_extern_symbol)
                    {
                        AddOneFunction (context, NULL, non_extern_symbol, current_id);
                        context.m_found.function = true;
                    }
                }
            }
            
            if (!context.m_found.function_with_type_info)
            {
                // Try the modules next.
                
                do
                {
                    if (ClangModulesDeclVendor *modules_decl_vendor = m_target->GetClangModulesDeclVendor())
                    {
                        bool append = false;
                        uint32_t max_matches = 1;
                        std::vector <clang::NamedDecl *> decls;
                        
                        if (!modules_decl_vendor->FindDecls(name,
                                                            append,
                                                            max_matches,
                                                            decls))
                            break;
                        
                        clang::NamedDecl *const decl_from_modules = decls[0];
                        
                        if (llvm::isa<clang::FunctionDecl>(decl_from_modules))
                        {
                            if (log)
                            {
                                log->Printf("  CAS::FEVD[%u] Matching function found for \"%s\" in the modules",
                                            current_id,
                                            name.GetCString());
                            }
                            
                            clang::Decl *copied_decl = m_ast_importer->CopyDecl(m_ast_context, &decl_from_modules->getASTContext(), decl_from_modules);
                            clang::FunctionDecl *copied_function_decl = copied_decl ? dyn_cast<clang::FunctionDecl>(copied_decl) : nullptr;
                            
                            if (!copied_function_decl)
                            {
                                if (log)
                                    log->Printf("  CAS::FEVD[%u] - Couldn't export a function declaration from the modules",
                                                current_id);
                                
                                break;
                            }
                            
                            if (copied_function_decl->getBody() && m_parser_vars->m_code_gen)
                            {
                                DeclGroupRef decl_group_ref(copied_function_decl);
                                m_parser_vars->m_code_gen->HandleTopLevelDecl(decl_group_ref);
                            }
                            
                            context.AddNamedDecl(copied_function_decl);
                            
                            context.m_found.function_with_type_info = true;
                            context.m_found.function = true;
                        }
                        else if (llvm::isa<clang::VarDecl>(decl_from_modules))
                        {
                            if (log)
                            {
                                log->Printf("  CAS::FEVD[%u] Matching variable found for \"%s\" in the modules",
                                            current_id,
                                            name.GetCString());
                            }
                            
                            clang::Decl *copied_decl = m_ast_importer->CopyDecl(m_ast_context, &decl_from_modules->getASTContext(), decl_from_modules);
                            clang::VarDecl *copied_var_decl = copied_decl ? dyn_cast_or_null<clang::VarDecl>(copied_decl) : nullptr;
                            
                            if (!copied_var_decl)
                            {
                                if (log)
                                    log->Printf("  CAS::FEVD[%u] - Couldn't export a variable declaration from the modules",
                                                current_id);
                                
                                break;
                            }
                            
                            context.AddNamedDecl(copied_var_decl);
                            
                            context.m_found.variable = true;
                        }
                    }
                } while (0);
            }

            if (target && !context.m_found.variable && !namespace_decl)
            {
                // We couldn't find a non-symbol variable for this.  Now we'll hunt for a generic
                // data symbol, and -- if it is found -- treat it as a variable.

                const Symbol *data_symbol = FindGlobalDataSymbol(*target, name);

                if (data_symbol)
                {
                    std::string warning("got name from symbols: ");
                    warning.append(name.AsCString());
                    const unsigned diag_id = m_ast_context->getDiagnostics().getCustomDiagID(clang::DiagnosticsEngine::Level::Warning, "%0");
                    m_ast_context->getDiagnostics().Report(diag_id) << warning.c_str();
                    AddOneGenericVariable(context, *data_symbol, current_id);
                    context.m_found.variable = true;
                }
            }
        }
    }
}

//static opaque_compiler_type_t
//MaybePromoteToBlockPointerType
//(
//    ASTContext *ast_context,
//    opaque_compiler_type_t candidate_type
//)
//{
//    if (!candidate_type)
//        return candidate_type;
//
//    QualType candidate_qual_type = QualType::getFromOpaquePtr(candidate_type);
//
//    const PointerType *candidate_pointer_type = dyn_cast<PointerType>(candidate_qual_type);
//
//    if (!candidate_pointer_type)
//        return candidate_type;
//
//    QualType pointee_qual_type = candidate_pointer_type->getPointeeType();
//
//    const RecordType *pointee_record_type = dyn_cast<RecordType>(pointee_qual_type);
//
//    if (!pointee_record_type)
//        return candidate_type;
//
//    RecordDecl *pointee_record_decl = pointee_record_type->getDecl();
//
//    if (!pointee_record_decl->isRecord())
//        return candidate_type;
//
//    if (!pointee_record_decl->getName().startswith(llvm::StringRef("__block_literal_")))
//        return candidate_type;
//
//    QualType generic_function_type = ast_context->getFunctionNoProtoType(ast_context->UnknownAnyTy);
//    QualType block_pointer_type = ast_context->getBlockPointerType(generic_function_type);
//
//    return block_pointer_type.getAsOpaquePtr();
//}

bool
ClangExpressionDeclMap::GetVariableValue (VariableSP &var,
                                          lldb_private::Value &var_location,
                                          TypeFromUser *user_type,
                                          TypeFromParser *parser_type)
{
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    Type *var_type = var->GetType();

    if (!var_type)
    {
        if (log)
            log->PutCString("Skipped a definition because it has no type");
        return false;
    }

    CompilerType var_clang_type = var_type->GetFullCompilerType ();

    if (!var_clang_type)
    {
        if (log)
            log->PutCString("Skipped a definition because it has no Clang type");
        return false;
    }

    ClangASTContext *clang_ast = llvm::dyn_cast_or_null<ClangASTContext>(var_type->GetForwardCompilerType().GetTypeSystem());

    if (!clang_ast)
    {
        if (log)
            log->PutCString("Skipped a definition because it has no Clang AST");
        return false;
    }


    ASTContext *ast = clang_ast->getASTContext();

    if (!ast)
    {
        if (log)
            log->PutCString("There is no AST context for the current execution context");
        return false;
    }
    //var_clang_type = MaybePromoteToBlockPointerType (ast, var_clang_type);

    DWARFExpression &var_location_expr = var->LocationExpression();

    Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();
    Error err;

    if (var->GetLocationIsConstantValueData())
    {
        DataExtractor const_value_extractor;

        if (var_location_expr.GetExpressionData(const_value_extractor))
        {
            var_location = Value(const_value_extractor.GetDataStart(), const_value_extractor.GetByteSize());
            var_location.SetValueType(Value::eValueTypeHostAddress);
        }
        else
        {
            if (log)
                log->Printf("Error evaluating constant variable: %s", err.AsCString());
            return false;
        }
    }

    CompilerType type_to_use = GuardedCopyType(var_clang_type);

    if (!type_to_use)
    {
        if (log)
            log->Printf("Couldn't copy a variable's type into the parser's AST context");

        return false;
    }

    if (parser_type)
        *parser_type = TypeFromParser(type_to_use);

    if (var_location.GetContextType() == Value::eContextTypeInvalid)
        var_location.SetCompilerType(type_to_use);

    if (var_location.GetValueType() == Value::eValueTypeFileAddress)
    {
        SymbolContext var_sc;
        var->CalculateSymbolContext(&var_sc);

        if (!var_sc.module_sp)
            return false;

        Address so_addr(var_location.GetScalar().ULongLong(), var_sc.module_sp->GetSectionList());

        lldb::addr_t load_addr = so_addr.GetLoadAddress(target);

        if (load_addr != LLDB_INVALID_ADDRESS)
        {
            var_location.GetScalar() = load_addr;
            var_location.SetValueType(Value::eValueTypeLoadAddress);
        }
    }

    if (user_type)
        *user_type = TypeFromUser(var_clang_type);

    return true;
}

void
ClangExpressionDeclMap::AddOneVariable (NameSearchContext &context, VariableSP var, ValueObjectSP valobj, unsigned int current_id)
{
    assert (m_parser_vars.get());

    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    TypeFromUser ut;
    TypeFromParser pt;
    Value var_location;

    if (!GetVariableValue (var, var_location, &ut, &pt))
        return;

    clang::QualType parser_opaque_type = QualType::getFromOpaquePtr(pt.GetOpaqueQualType());

    if (parser_opaque_type.isNull())
        return;

    if (const clang::Type *parser_type = parser_opaque_type.getTypePtr())
    {
        if (const TagType *tag_type = dyn_cast<TagType>(parser_type))
            CompleteType(tag_type->getDecl());
        if (const ObjCObjectPointerType *objc_object_ptr_type = dyn_cast<ObjCObjectPointerType>(parser_type))
            CompleteType(objc_object_ptr_type->getInterfaceDecl());
    }


    bool is_reference = pt.IsReferenceType();

    NamedDecl *var_decl = NULL;
    if (is_reference)
        var_decl = context.AddVarDecl(pt);
    else
        var_decl = context.AddVarDecl(pt.GetLValueReferenceType());

    std::string decl_name(context.m_decl_name.getAsString());
    ConstString entity_name(decl_name.c_str());
    ClangExpressionVariable *entity(new ClangExpressionVariable(valobj));
    m_found_entities.AddNewlyConstructedVariable(entity);

    assert (entity);
    entity->EnableParserVars(GetParserID());
    ClangExpressionVariable::ParserVars *parser_vars = entity->GetParserVars(GetParserID());
    parser_vars->m_parser_type = pt;
    parser_vars->m_named_decl  = var_decl;
    parser_vars->m_llvm_value  = NULL;
    parser_vars->m_lldb_value  = var_location;
    parser_vars->m_lldb_var    = var;

    if (is_reference)
        entity->m_flags |= ClangExpressionVariable::EVTypeIsReference;

    if (log)
    {
        ASTDumper orig_dumper(ut.GetOpaqueQualType());
        ASTDumper ast_dumper(var_decl);
        log->Printf("  CEDM::FEVD[%u] Found variable %s, returned %s (original %s)", current_id, decl_name.c_str(), ast_dumper.GetCString(), orig_dumper.GetCString());
    }
}

void
ClangExpressionDeclMap::AddOneVariable(NameSearchContext &context,
                                       ExpressionVariableSP &pvar_sp,
                                       unsigned int current_id)
{
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    TypeFromUser user_type (llvm::cast<ClangExpressionVariable>(pvar_sp.get())->GetTypeFromUser());

    TypeFromParser parser_type (GuardedCopyType(user_type));

    if (!parser_type.GetOpaqueQualType())
    {
        if (log)
            log->Printf("  CEDM::FEVD[%u] Couldn't import type for pvar %s", current_id, pvar_sp->GetName().GetCString());
        return;
    }

    NamedDecl *var_decl = context.AddVarDecl(parser_type.GetLValueReferenceType());

    llvm::cast<ClangExpressionVariable>(pvar_sp.get())->EnableParserVars(GetParserID());
    ClangExpressionVariable::ParserVars *parser_vars = llvm::cast<ClangExpressionVariable>(pvar_sp.get())->GetParserVars(GetParserID());
    parser_vars->m_parser_type = parser_type;
    parser_vars->m_named_decl = var_decl;
    parser_vars->m_llvm_value = NULL;
    parser_vars->m_lldb_value.Clear();

    if (log)
    {
        ASTDumper ast_dumper(var_decl);
        log->Printf("  CEDM::FEVD[%u] Added pvar %s, returned %s", current_id, pvar_sp->GetName().GetCString(), ast_dumper.GetCString());
    }
}

void
ClangExpressionDeclMap::AddOneGenericVariable(NameSearchContext &context,
                                              const Symbol &symbol,
                                              unsigned int current_id)
{
    assert(m_parser_vars.get());

    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();

    if (target == NULL)
        return;

    ASTContext *scratch_ast_context = target->GetScratchClangASTContext()->getASTContext();

    TypeFromUser user_type (ClangASTContext::GetBasicType(scratch_ast_context, eBasicTypeVoid).GetPointerType().GetLValueReferenceType());
    TypeFromParser parser_type (ClangASTContext::GetBasicType(m_ast_context, eBasicTypeVoid).GetPointerType().GetLValueReferenceType());
    NamedDecl *var_decl = context.AddVarDecl(parser_type);

    std::string decl_name(context.m_decl_name.getAsString());
    ConstString entity_name(decl_name.c_str());
    ClangExpressionVariable *entity(new ClangExpressionVariable(m_parser_vars->m_exe_ctx.GetBestExecutionContextScope (),
                                                                entity_name,
                                                                user_type,
                                                                m_parser_vars->m_target_info.byte_order,
                                                                m_parser_vars->m_target_info.address_byte_size));
    m_found_entities.AddNewlyConstructedVariable(entity);
    
    entity->EnableParserVars(GetParserID());
    ClangExpressionVariable::ParserVars *parser_vars = entity->GetParserVars(GetParserID());

    const Address symbol_address = symbol.GetAddress();
    lldb::addr_t symbol_load_addr = symbol_address.GetLoadAddress(target);

    //parser_vars->m_lldb_value.SetContext(Value::eContextTypeClangType, user_type.GetOpaqueQualType());
    parser_vars->m_lldb_value.SetCompilerType(user_type);
    parser_vars->m_lldb_value.GetScalar() = symbol_load_addr;
    parser_vars->m_lldb_value.SetValueType(Value::eValueTypeLoadAddress);

    parser_vars->m_parser_type = parser_type;
    parser_vars->m_named_decl  = var_decl;
    parser_vars->m_llvm_value  = NULL;
    parser_vars->m_lldb_sym    = &symbol;

    if (log)
    {
        ASTDumper ast_dumper(var_decl);

        log->Printf("  CEDM::FEVD[%u] Found variable %s, returned %s", current_id, decl_name.c_str(), ast_dumper.GetCString());
    }
}

bool
ClangExpressionDeclMap::ResolveUnknownTypes()
{
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
    Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();

    ClangASTContext *scratch_ast_context = target->GetScratchClangASTContext();

    for (size_t index = 0, num_entities = m_found_entities.GetSize();
         index < num_entities;
         ++index)
    {
        ExpressionVariableSP entity = m_found_entities.GetVariableAtIndex(index);

        ClangExpressionVariable::ParserVars *parser_vars = llvm::cast<ClangExpressionVariable>(entity.get())->GetParserVars(GetParserID());

        if (entity->m_flags & ClangExpressionVariable::EVUnknownType)
        {
            const NamedDecl *named_decl = parser_vars->m_named_decl;
            const VarDecl *var_decl = dyn_cast<VarDecl>(named_decl);

            if (!var_decl)
            {
                if (log)
                    log->Printf("Entity of unknown type does not have a VarDecl");
                return false;
            }

            if (log)
            {
                ASTDumper ast_dumper(const_cast<VarDecl*>(var_decl));
                log->Printf("Variable of unknown type now has Decl %s", ast_dumper.GetCString());
            }

            QualType var_type = var_decl->getType();
            TypeFromParser parser_type(var_type.getAsOpaquePtr(), ClangASTContext::GetASTContext(&var_decl->getASTContext()));

            lldb::opaque_compiler_type_t copied_type = m_ast_importer->CopyType(scratch_ast_context->getASTContext(), &var_decl->getASTContext(), var_type.getAsOpaquePtr());

            if (!copied_type)
            {
                if (log)
                    log->Printf("ClangExpressionDeclMap::ResolveUnknownType - Couldn't import the type for a variable");

                return (bool) lldb::ExpressionVariableSP();
            }

            TypeFromUser user_type(copied_type, scratch_ast_context);

//            parser_vars->m_lldb_value.SetContext(Value::eContextTypeClangType, user_type.GetOpaqueQualType());
            parser_vars->m_lldb_value.SetCompilerType(user_type);
            parser_vars->m_parser_type = parser_type;

            entity->SetCompilerType(user_type);

            entity->m_flags &= ~(ClangExpressionVariable::EVUnknownType);
        }
    }

    return true;
}

void
ClangExpressionDeclMap::AddOneRegister (NameSearchContext &context,
                                        const RegisterInfo *reg_info,
                                        unsigned int current_id)
{
    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    CompilerType clang_type = ClangASTContext::GetBuiltinTypeForEncodingAndBitSize (m_ast_context,
                                                                                    reg_info->encoding,
                                                                                    reg_info->byte_size * 8);

    if (!clang_type)
    {
        if (log)
            log->Printf("  Tried to add a type for %s, but couldn't get one", context.m_decl_name.getAsString().c_str());
        return;
    }

    TypeFromParser parser_clang_type (clang_type);

    NamedDecl *var_decl = context.AddVarDecl(parser_clang_type);

    ClangExpressionVariable *entity(new ClangExpressionVariable(m_parser_vars->m_exe_ctx.GetBestExecutionContextScope(),
                                                                m_parser_vars->m_target_info.byte_order,
                                                                m_parser_vars->m_target_info.address_byte_size));
    m_found_entities.AddNewlyConstructedVariable(entity);

    std::string decl_name(context.m_decl_name.getAsString());
    entity->SetName (ConstString (decl_name.c_str()));
    entity->SetRegisterInfo (reg_info);
    entity->EnableParserVars(GetParserID());
    ClangExpressionVariable::ParserVars *parser_vars = entity->GetParserVars(GetParserID());
    parser_vars->m_parser_type = parser_clang_type;
    parser_vars->m_named_decl = var_decl;
    parser_vars->m_llvm_value = NULL;
    parser_vars->m_lldb_value.Clear();
    entity->m_flags |= ClangExpressionVariable::EVBareRegister;

    if (log)
    {
        ASTDumper ast_dumper(var_decl);
        log->Printf("  CEDM::FEVD[%d] Added register %s, returned %s", current_id, context.m_decl_name.getAsString().c_str(), ast_dumper.GetCString());
    }
}

void
ClangExpressionDeclMap::AddOneFunction (NameSearchContext &context,
                                        Function* function,
                                        Symbol* symbol,
                                        unsigned int current_id)
{
    assert (m_parser_vars.get());

    Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

    NamedDecl *function_decl = NULL;
    Address fun_address;
    CompilerType function_clang_type;

    bool is_indirect_function = false;

    if (function)
    {
        Type *function_type = function->GetType();

        if (!function_type)
        {
            if (log)
                log->PutCString("  Skipped a function because it has no type");
            return;
        }

        function_clang_type = function_type->GetFullCompilerType ();

        if (!function_clang_type)
        {
            if (log)
                log->PutCString("  Skipped a function because it has no Clang type");
            return;
        }

        fun_address = function->GetAddressRange().GetBaseAddress();

        CompilerType copied_function_type = GuardedCopyType(function_clang_type);
        if (copied_function_type)
        {
            function_decl = context.AddFunDecl(copied_function_type);

            if (!function_decl)
            {
                if (log)
                {
                    log->Printf ("  Failed to create a function decl for '%s' {0x%8.8" PRIx64 "}",
                                 function_type->GetName().GetCString(),
                                 function_type->GetID());
                }

                return;
            }
        }
        else
        {
            // We failed to copy the type we found
            if (log)
            {
                log->Printf ("  Failed to import the function type '%s' {0x%8.8" PRIx64 "} into the expression parser AST contenxt",
                             function_type->GetName().GetCString(),
                             function_type->GetID());
            }

            return;
        }
    }
    else if (symbol)
    {
        fun_address = symbol->GetAddress();
        function_decl = context.AddGenericFunDecl();
        is_indirect_function = symbol->IsIndirect();
    }
    else
    {
        if (log)
            log->PutCString("  AddOneFunction called with no function and no symbol");
        return;
    }

    Target *target = m_parser_vars->m_exe_ctx.GetTargetPtr();

    lldb::addr_t load_addr = fun_address.GetCallableLoadAddress(target, is_indirect_function);

    ClangExpressionVariable *entity(new ClangExpressionVariable (m_parser_vars->m_exe_ctx.GetBestExecutionContextScope (),
                                                                 m_parser_vars->m_target_info.byte_order,
                                                                 m_parser_vars->m_target_info.address_byte_size));
    m_found_entities.AddNewlyConstructedVariable(entity);

    std::string decl_name(context.m_decl_name.getAsString());
    entity->SetName(ConstString(decl_name.c_str()));
    entity->SetCompilerType (function_clang_type);
    entity->EnableParserVars(GetParserID());

    ClangExpressionVariable::ParserVars *parser_vars = entity->GetParserVars(GetParserID());

    if (load_addr != LLDB_INVALID_ADDRESS)
    {
        parser_vars->m_lldb_value.SetValueType(Value::eValueTypeLoadAddress);
        parser_vars->m_lldb_value.GetScalar() = load_addr;
    }
    else
    {
        // We have to try finding a file address.

        lldb::addr_t file_addr = fun_address.GetFileAddress();

        parser_vars->m_lldb_value.SetValueType(Value::eValueTypeFileAddress);
        parser_vars->m_lldb_value.GetScalar() = file_addr;
    }


    parser_vars->m_named_decl  = function_decl;
    parser_vars->m_llvm_value  = NULL;

    if (log)
    {
        ASTDumper ast_dumper(function_decl);

        StreamString ss;

        fun_address.Dump(&ss, m_parser_vars->m_exe_ctx.GetBestExecutionContextScope(), Address::DumpStyleResolvedDescription);

        log->Printf("  CEDM::FEVD[%u] Found %s function %s (description %s), returned %s",
                    current_id,
                    (function ? "specific" : "generic"),
                    decl_name.c_str(),
                    ss.GetData(),
                    ast_dumper.GetCString());
    }
}

TypeFromParser
ClangExpressionDeclMap::CopyClassType(TypeFromUser &ut,
                                      unsigned int current_id)
{
    CompilerType copied_clang_type = GuardedCopyType(ut);

    if (!copied_clang_type)
    {
        Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

        if (log)
            log->Printf("ClangExpressionDeclMap::CopyClassType - Couldn't import the type");

        return TypeFromParser();
    }

    if (copied_clang_type.IsAggregateType() && copied_clang_type.GetCompleteType ())
    {
        CompilerType void_clang_type = ClangASTContext::GetBasicType(m_ast_context, eBasicTypeVoid);
        CompilerType void_ptr_clang_type = void_clang_type.GetPointerType();

        CompilerType method_type = ClangASTContext::CreateFunctionType (m_ast_context,
                                                                        void_clang_type,
                                                                        &void_ptr_clang_type,
                                                                        1,
                                                                        false,
                                                                        copied_clang_type.GetTypeQualifiers());

        const bool is_virtual = false;
        const bool is_static = false;
        const bool is_inline = false;
        const bool is_explicit = false;
        const bool is_attr_used = true;
        const bool is_artificial = false;

        ClangASTContext::GetASTContext(m_ast_context)->
            AddMethodToCXXRecordType (copied_clang_type.GetOpaqueQualType(),
                                      "$__lldb_expr",
                                      method_type,
                                      lldb::eAccessPublic,
                                      is_virtual,
                                      is_static,
                                      is_inline,
                                      is_explicit,
                                      is_attr_used,
                                      is_artificial);
    }

    return TypeFromParser(copied_clang_type);
}

void
ClangExpressionDeclMap::AddOneType(NameSearchContext &context,
                                   TypeFromUser &ut,
                                   unsigned int current_id)
{
    CompilerType copied_clang_type = GuardedCopyType(ut);

    if (!copied_clang_type)
    {
        Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));

        if (log)
            log->Printf("ClangExpressionDeclMap::AddOneType - Couldn't import the type");

        return;
    }

    context.AddTypeDecl(copied_clang_type);
}