Index: include/lldb/Symbol/ClangASTContext.h
===================================================================
--- include/lldb/Symbol/ClangASTContext.h
+++ include/lldb/Symbol/ClangASTContext.h
@@ -564,6 +564,9 @@
     ConstString
     DeclContextGetName (void *opaque_decl_ctx) override;
 
+    ConstString
+    DeclContextGetScopeQualifiedName (void *opaque_decl_ctx) override;
+
     bool
     DeclContextIsClassMethod (void *opaque_decl_ctx,
                               lldb::LanguageType *language_ptr,
Index: include/lldb/Symbol/CompilerDeclContext.h
===================================================================
--- include/lldb/Symbol/CompilerDeclContext.h
+++ include/lldb/Symbol/CompilerDeclContext.h
@@ -128,6 +128,9 @@
     ConstString
     GetName () const;
 
+    ConstString
+    GetScopeQualifiedName() const;
+
     bool
     IsStructUnionOrClass () const;
 
Index: include/lldb/Symbol/GoASTContext.h
===================================================================
--- include/lldb/Symbol/GoASTContext.h
+++ include/lldb/Symbol/GoASTContext.h
@@ -118,6 +118,12 @@
         return ConstString();
     }
 
+    ConstString
+    DeclContextGetScopeQualifiedName(void *opaque_decl_ctx) override
+    {
+        return ConstString();
+    }
+
     bool
     DeclContextIsClassMethod(void *opaque_decl_ctx, lldb::LanguageType *language_ptr, bool *is_instance_method_ptr,
                              ConstString *language_object_name_ptr) override
Index: include/lldb/Symbol/SymbolFile.h
===================================================================
--- include/lldb/Symbol/SymbolFile.h
+++ include/lldb/Symbol/SymbolFile.h
@@ -142,6 +142,7 @@
     virtual uint32_t        FindFunctions (const ConstString &name, const CompilerDeclContext *parent_decl_ctx, uint32_t name_type_mask, bool include_inlines, bool append, SymbolContextList& sc_list);
     virtual uint32_t        FindFunctions (const RegularExpression& regex, bool include_inlines, bool append, SymbolContextList& sc_list);
     virtual uint32_t        FindTypes (const SymbolContext& sc, const ConstString &name, const CompilerDeclContext *parent_decl_ctx, bool append, uint32_t max_matches, TypeMap& types);
+    virtual void            GetMangledNamesForFunction(const std::string &scope_qualified_name, std::vector<ConstString> &mangled_names);
 //  virtual uint32_t        FindTypes (const SymbolContext& sc, const RegularExpression& regex, bool append, uint32_t max_matches, TypeList& types) = 0;
     virtual TypeList *      GetTypeList ();
     virtual size_t          GetTypes (lldb_private::SymbolContextScope *sc_scope,
Index: include/lldb/Symbol/TypeSystem.h
===================================================================
--- include/lldb/Symbol/TypeSystem.h
+++ include/lldb/Symbol/TypeSystem.h
@@ -150,6 +150,9 @@
     virtual ConstString
     DeclContextGetName (void *opaque_decl_ctx) = 0;
 
+    virtual ConstString
+    DeclContextGetScopeQualifiedName (void *opaque_decl_ctx) = 0;
+
     virtual bool
     DeclContextIsClassMethod (void *opaque_decl_ctx,
                               lldb::LanguageType *language_ptr,
Index: include/lldb/Target/CPPLanguageRuntime.h
===================================================================
--- include/lldb/Target/CPPLanguageRuntime.h
+++ include/lldb/Target/CPPLanguageRuntime.h
@@ -42,9 +42,6 @@
     bool
     GetObjectDescription(Stream &str, Value &value, ExecutionContextScope *exe_scope) override;
     
-    virtual size_t
-    GetAlternateManglings(const ConstString &mangled, std::vector<ConstString> &alternates) = 0;
-
 protected:
 
     //------------------------------------------------------------------
Index: source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp
===================================================================
--- source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp
+++ source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp
@@ -36,6 +36,7 @@
 #include "lldb/Symbol/Function.h"
 #include "lldb/Symbol/ObjectFile.h"
 #include "lldb/Symbol/SymbolContext.h"
+#include "lldb/Symbol/SymbolFile.h"
 #include "lldb/Symbol/SymbolVendor.h"
 #include "lldb/Symbol/Type.h"
 #include "lldb/Symbol/TypeList.h"
@@ -570,6 +571,63 @@
     }
 }
 
+ConstString
+FindBestAlternateMangledName
+(
+    const ConstString &demangled,
+    const LanguageType &lang_type,
+    SymbolContext &sym_ctx
+)
+{
+    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++)
+    {
+        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);
+        }
+    }
+
+    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();
+}
+
 bool
 ClangExpressionDeclMap::GetFunctionAddress
 (
@@ -603,15 +661,25 @@
             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();
+                    ConstString best_alternate_mangled_name = FindBestAlternateMangledName(demangled, lang_type, sc);
+                    if (best_alternate_mangled_name)
+                    {
+                        FindCodeSymbolInContext(
+                            best_alternate_mangled_name, m_parser_vars->m_sym_ctx, eFunctionNameTypeAuto, sc_list);
+                        sc_list_size = sc_list.GetSize();
+                    }
+
+                    if (sc_list_size == 0)
+                    {
+                        FindCodeSymbolInContext(
+                            demangled, m_parser_vars->m_sym_ctx, eFunctionNameTypeFull, sc_list);
+                        sc_list_size = sc_list.GetSize();
+                    }
                 }
             }
         }
Index: source/Plugins/ExpressionParser/Clang/IRForTarget.cpp
===================================================================
--- source/Plugins/ExpressionParser/Clang/IRForTarget.cpp
+++ source/Plugins/ExpressionParser/Clang/IRForTarget.cpp
@@ -36,7 +36,6 @@
 #include "lldb/Host/Endian.h"
 #include "lldb/Symbol/ClangASTContext.h"
 #include "lldb/Symbol/CompilerType.h"
-#include "lldb/Target/CPPLanguageRuntime.h"
 
 #include <map>
 
@@ -230,36 +229,6 @@
         {
             std::vector<lldb_private::ConstString> alternates;
             bool found_it = m_decl_map->GetFunctionAddress (name, fun_addr);
-            if (!found_it)
-            {
-                if (log)
-                    log->Printf("Address of function \"%s\" not found.\n", name.GetCString());
-                // Check for an alternate mangling for names from the standard library.
-                // For example, "std::basic_string<...>" has an alternate mangling scheme per
-                // the Itanium C++ ABI.
-                lldb::ProcessSP process_sp = m_data_allocator.GetTarget()->GetProcessSP();
-                if (process_sp)
-                {
-                    lldb_private::CPPLanguageRuntime *cpp_runtime = process_sp->GetCPPLanguageRuntime();
-                    if (cpp_runtime && cpp_runtime->GetAlternateManglings(name, alternates))
-                    {
-                        for (size_t i = 0; i < alternates.size(); ++i)
-                        {
-                            const lldb_private::ConstString &alternate_name = alternates[i];
-                            if (log)
-                                log->Printf("Looking up address of function \"%s\" with alternate name \"%s\"",
-                                            name.GetCString(), alternate_name.GetCString());
-                            if ((found_it = m_decl_map->GetFunctionAddress (alternate_name, fun_addr)))
-                            {
-                                if (log)
-                                    log->Printf("Found address of function \"%s\" with alternate name \"%s\"",
-                                                name.GetCString(), alternate_name.GetCString());
-                                break;
-                            }
-                        }
-                    }
-                }
-            }
 
             if (!found_it)
             {
Index: source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.h
===================================================================
--- source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.h
+++ source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.h
@@ -89,6 +89,9 @@
         {
             return m_full;
         }
+
+        std::string
+        GetScopeQualifiedName ();
         
         llvm::StringRef
         GetBasename ();
Index: source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.cpp
===================================================================
--- source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.cpp
+++ source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.cpp
@@ -296,6 +296,22 @@
     return m_qualifiers;
 }
 
+std::string
+CPlusPlusLanguage::MethodName::GetScopeQualifiedName ()
+{
+    if (!m_parsed)
+        Parse();
+    if (m_basename.empty() || m_context.empty())
+        return std::string();
+
+    std::string res;
+    res += m_context;
+    res += "::";
+    res += m_basename;
+
+    return res;
+}
+
 bool
 CPlusPlusLanguage::IsCPPMangledName (const char *name)
 {
Index: source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h
===================================================================
--- source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h
+++ source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.h
@@ -80,9 +80,6 @@
         lldb::SearchFilterSP
         CreateExceptionSearchFilter() override;
 
-        size_t
-        GetAlternateManglings(const ConstString &mangled, std::vector<ConstString> &alternates) override;
-
         //------------------------------------------------------------------
         // PluginInterface protocol
         //------------------------------------------------------------------
Index: source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
===================================================================
--- source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
+++ source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
@@ -319,46 +319,6 @@
         return false;
 }
 
-static std::map<ConstString, std::vector<ConstString> >&
-GetAlternateManglingPrefixes()
-{
-    static std::map<ConstString, std::vector<ConstString> > g_alternate_mangling_prefixes;
-    return g_alternate_mangling_prefixes;
-}
-
-
-size_t
-ItaniumABILanguageRuntime::GetAlternateManglings(const ConstString &mangled, std::vector<ConstString> &alternates)
-{
-    if (!mangled)
-        return static_cast<size_t>(0);
-
-    alternates.clear();
-    const char *mangled_cstr = mangled.AsCString();
-    std::map<ConstString, std::vector<ConstString> >& alternate_mangling_prefixes = GetAlternateManglingPrefixes();
-    for (std::map<ConstString, std::vector<ConstString> >::iterator it = alternate_mangling_prefixes.begin();
-         it != alternate_mangling_prefixes.end();
-         ++it)
-    {
-        const char *prefix_cstr = it->first.AsCString();
-        if (strncmp(mangled_cstr, prefix_cstr, strlen(prefix_cstr)) == 0)
-        {
-            const std::vector<ConstString> &alternate_prefixes = it->second;
-            for (size_t i = 0; i < alternate_prefixes.size(); ++i)
-            {
-                std::string alternate_mangling(alternate_prefixes[i].AsCString());
-                alternate_mangling.append(mangled_cstr + strlen(prefix_cstr));
-
-                alternates.push_back(ConstString(alternate_mangling.c_str()));
-            }
-
-            return alternates.size();
-        }
-    }
-
-    return static_cast<size_t>(0);
-}
-
 //------------------------------------------------------------------
 // Static Functions
 //------------------------------------------------------------------
@@ -382,17 +342,6 @@
     PluginManager::RegisterPlugin (GetPluginNameStatic(),
                                    "Itanium ABI for the C++ language",
                                    CreateInstance);    
-
-    // Alternate manglings for std::basic_string<...>
-    std::vector<ConstString> basic_string_alternates;
-    basic_string_alternates.push_back(ConstString("_ZNSs"));
-    basic_string_alternates.push_back(ConstString("_ZNKSs"));
-    std::map<ConstString, std::vector<ConstString> >& alternate_mangling_prefixes = GetAlternateManglingPrefixes();
-
-    alternate_mangling_prefixes[ConstString("_ZNSbIcSt17char_traits<char>St15allocator<char>E")] =
-        basic_string_alternates;
-    alternate_mangling_prefixes[ConstString("_ZNKSbIcSt17char_traits<char>St15allocator<char>E")] =
-        basic_string_alternates;
 }
 
 void
Index: source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.h
===================================================================
--- source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.h
+++ source/Plugins/LanguageRuntime/RenderScript/RenderScriptRuntime/RenderScriptRuntime.h
@@ -207,10 +207,6 @@
 
     void Status(Stream &strm) const;
 
-    size_t GetAlternateManglings(const ConstString &mangled, std::vector<ConstString> &alternates) override {
-        return static_cast<size_t>(0);
-    }
-
     void ModulesDidLoad(const ModuleList &module_list) override;
 
     bool LoadAllocation(Stream &strm, const uint32_t alloc_id, const char* filename, StackFrame* frame_ptr);
Index: source/Plugins/SymbolFile/DWARF/DIERef.h
===================================================================
--- source/Plugins/SymbolFile/DWARF/DIERef.h
+++ source/Plugins/SymbolFile/DWARF/DIERef.h
@@ -33,6 +33,18 @@
     lldb::user_id_t
     GetUID() const;
 
+    bool
+    operator< (const DIERef &ref) const
+    {
+        return die_offset < ref.die_offset;
+    }
+
+    bool
+    operator< (const DIERef &ref)
+    {
+        return die_offset < ref.die_offset;
+    }
+
     dw_offset_t cu_offset;
     dw_offset_t die_offset;
 };
Index: source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
===================================================================
--- source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
+++ source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
@@ -16,6 +16,7 @@
 #include <map>
 #include <mutex>
 #include <set>
+#include <unordered_map>
 #include <vector>
 
 // Other libraries and framework includes
@@ -203,6 +204,10 @@
                    bool append,
                    lldb_private::SymbolContextList& sc_list) override;
 
+    void
+    GetMangledNamesForFunction (const std::string &scope_qualified_name,
+                                std::vector<lldb_private::ConstString> &mangled_names) override;
+
     uint32_t
     FindTypes (const lldb_private::SymbolContext& sc,
                const lldb_private::ConstString &name,
@@ -560,6 +565,9 @@
                                         m_fetched_external_modules:1;
     lldb_private::LazyBool              m_supports_DW_AT_APPLE_objc_complete_type;
 
+    typedef std::shared_ptr<std::set<DIERef> > DIERefSetSP;
+    typedef std::unordered_map<std::string, DIERefSetSP> NameToOffsetMap;
+    NameToOffsetMap m_function_scope_qualified_name_map;
     std::unique_ptr<DWARFDebugRanges>     m_ranges;
     UniqueDWARFASTTypeMap m_unique_ast_type_map;
     DIEToTypePtr m_die_to_type;
Index: source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
===================================================================
--- source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
+++ source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
@@ -2856,6 +2856,40 @@
     return sc_list.GetSize() - original_size;
 }
 
+void
+SymbolFileDWARF::GetMangledNamesForFunction (const std::string &scope_qualified_name,
+                                             std::vector<ConstString> &mangled_names)
+{
+    DWARFDebugInfo* info = DebugInfo();
+    uint32_t num_comp_units = 0;
+    if (info)
+        num_comp_units = info->GetNumCompileUnits();
+
+    for (uint32_t i = 0; i < num_comp_units; i++)
+    {
+        DWARFCompileUnit *cu = info->GetCompileUnitAtIndex(i);
+        if (cu == nullptr)
+            continue;
+
+        SymbolFileDWARFDwo *dwo = cu->GetDwoSymbolFile();
+        if (dwo)
+            dwo->GetMangledNamesForFunction(scope_qualified_name, mangled_names);
+    }
+
+    NameToOffsetMap::iterator iter = m_function_scope_qualified_name_map.find(scope_qualified_name);
+    if (iter == m_function_scope_qualified_name_map.end())
+        return;
+
+    DIERefSetSP set_sp = (*iter).second;
+    std::set<DIERef>::iterator set_iter;
+    for (set_iter = set_sp->begin(); set_iter != set_sp->end(); set_iter++)
+    {
+        DWARFDIE die = DebugInfo()->GetDIE (*set_iter);
+        mangled_names.push_back(ConstString(die.GetMangledName()));
+    }
+}
+
+
 uint32_t
 SymbolFileDWARF::FindTypes (const SymbolContext& sc, 
                             const ConstString &name, 
@@ -3582,6 +3616,24 @@
                     TypeList* type_list = GetTypeList();
                     if (type_list)
                         type_list->Insert(type_sp);
+
+                    if (die.Tag() == DW_TAG_subprogram)
+                    {
+                        DIERef die_ref = die.GetDIERef();
+                        std::string scope_qualified_name(GetDeclContextForUID(die.GetID()).GetScopeQualifiedName().AsCString());
+                        if (scope_qualified_name.size())
+                        {
+                            NameToOffsetMap::iterator iter = m_function_scope_qualified_name_map.find(scope_qualified_name);
+                            if (iter != m_function_scope_qualified_name_map.end())
+                                (*iter).second->insert(die_ref);
+                            else
+                            {
+                                DIERefSetSP new_set(new std::set<DIERef>);
+                                new_set->insert(die_ref);
+                                m_function_scope_qualified_name_map.emplace(std::make_pair(scope_qualified_name, new_set));
+                            }
+                        }
+                    }
                 }
             }
         }
Index: source/Symbol/ClangASTContext.cpp
===================================================================
--- source/Symbol/ClangASTContext.cpp
+++ source/Symbol/ClangASTContext.cpp
@@ -9245,6 +9245,18 @@
     return ConstString();
 }
 
+ConstString
+ClangASTContext::DeclContextGetScopeQualifiedName (void *opaque_decl_ctx)
+{
+    if (opaque_decl_ctx)
+    {
+        clang::NamedDecl *named_decl = llvm::dyn_cast<clang::NamedDecl>((clang::DeclContext *)opaque_decl_ctx);
+        if (named_decl)
+            return ConstString(llvm::StringRef(named_decl->getQualifiedNameAsString()));
+    }
+    return ConstString();
+}
+
 bool
 ClangASTContext::DeclContextIsClassMethod (void *opaque_decl_ctx,
                                            lldb::LanguageType *language_ptr,
Index: source/Symbol/CompilerDeclContext.cpp
===================================================================
--- source/Symbol/CompilerDeclContext.cpp
+++ source/Symbol/CompilerDeclContext.cpp
@@ -42,6 +42,15 @@
         return ConstString();
 }
 
+ConstString
+CompilerDeclContext::GetScopeQualifiedName () const
+{
+    if (IsValid())
+        return m_type_system->DeclContextGetScopeQualifiedName(m_opaque_decl_ctx);
+    else
+        return ConstString();
+}
+
 bool
 CompilerDeclContext::IsStructUnionOrClass () const
 {
Index: source/Symbol/SymbolFile.cpp
===================================================================
--- source/Symbol/SymbolFile.cpp
+++ source/Symbol/SymbolFile.cpp
@@ -134,6 +134,12 @@
     return 0;
 }
 
+void
+SymbolFile::GetMangledNamesForFunction(const std::string &scope_qualified_name, std::vector<ConstString> &mangled_names)
+{
+    return;
+}
+
 uint32_t
 SymbolFile::FindTypes (const SymbolContext& sc, const ConstString &name, const CompilerDeclContext *parent_decl_ctx, bool append, uint32_t max_matches, TypeMap& types)
 {