Vendor import of (stripped) lldb trunk r242221:vendor/lldb/lldb-trunk-r242221

https://llvm.org/svn/llvm-project/lldb/trunk@242221

42 files changed, 856 insertions, 285 deletions

diff --git a/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp b/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
index 0853fe286963..4204d18769b8 100644
--- a/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
+++ b/source/Plugins/ABI/MacOSX-i386/ABIMacOSX_i386.cpp
@@ -236,7 +236,8 @@ ABISP
 ABIMacOSX_i386::CreateInstance (const ArchSpec &arch)
 {
     static ABISP g_abi_sp;
-     if (arch.GetTriple().getArch() == llvm::Triple::x86)
+     if ((arch.GetTriple().getArch() == llvm::Triple::x86) &&
+          (arch.GetTriple().isMacOSX() || arch.GetTriple().isiOS()))
      {
         if (!g_abi_sp)
             g_abi_sp.reset (new ABIMacOSX_i386);
diff --git a/source/Plugins/ABI/SysV-hexagon/ABISysV_hexagon.cpp b/source/Plugins/ABI/SysV-hexagon/ABISysV_hexagon.cpp
index e9e68bc0e949..69129df1f16b 100644
--- a/source/Plugins/ABI/SysV-hexagon/ABISysV_hexagon.cpp
+++ b/source/Plugins/ABI/SysV-hexagon/ABISysV_hexagon.cpp
@@ -257,7 +257,7 @@ ABISysV_hexagon::PrepareTrivialCall ( Thread &thread,
         sp -= argSize;
 
         // write this argument onto the stack of the host process
-        proc.get( )->WriteMemory( sp, arg.data, arg.size, error );
+        proc.get( )->WriteMemory( sp, arg.data_ap.get(), arg.size, error );
         if ( error.Fail( ) )
             return false;
 
diff --git a/source/Plugins/DynamicLoader/Hexagon-DYLD/DynamicLoaderHexagonDYLD.cpp b/source/Plugins/DynamicLoader/Hexagon-DYLD/DynamicLoaderHexagonDYLD.cpp
index bbafcf73fa16..2308129b8cab 100644
--- a/source/Plugins/DynamicLoader/Hexagon-DYLD/DynamicLoaderHexagonDYLD.cpp
+++ b/source/Plugins/DynamicLoader/Hexagon-DYLD/DynamicLoaderHexagonDYLD.cpp
@@ -168,6 +168,9 @@ DynamicLoaderHexagonDYLD::DidAttach()
     // Disable JIT for hexagon targets because its not supported
     m_process->SetCanJIT(false);
 
+    // Enable Interpreting of function call expressions
+    m_process->SetCanInterpretFunctionCalls(true);
+
     // Add the current executable to the module list
     ModuleList module_list;
     module_list.Append(executable);
@@ -500,7 +503,7 @@ DynamicLoaderHexagonDYLD::GetStepThroughTrampolinePlan(Thread &thread, bool stop
     if (sym == NULL || !sym->IsTrampoline())
         return thread_plan_sp;
 
-    const ConstString &sym_name = sym->GetMangled().GetName(Mangled::ePreferMangled);
+    const ConstString sym_name = sym->GetMangled().GetName(lldb::eLanguageTypeUnknown, Mangled::ePreferMangled);
     if (!sym_name)
         return thread_plan_sp;
 
diff --git a/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp b/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp
index 6330b42ca14a..8724fc039cb9 100644
--- a/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp
+++ b/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp
@@ -458,7 +458,7 @@ DynamicLoaderPOSIXDYLD::GetStepThroughTrampolinePlan(Thread &thread, bool stop)
     if (sym == NULL || !sym->IsTrampoline())
         return thread_plan_sp;
 
-    const ConstString &sym_name = sym->GetMangled().GetName(Mangled::ePreferMangled);
+    ConstString sym_name = sym->GetName();
     if (!sym_name)
         return thread_plan_sp;
 
@@ -667,7 +667,9 @@ DynamicLoaderPOSIXDYLD::ResolveExecutableModule (lldb::ModuleSP &module_sp)
     if (module_sp && module_sp->MatchesModuleSpec (module_spec))
         return;
 
-    auto error = platform_sp->ResolveExecutable (module_spec, module_sp, nullptr);
+    const auto executable_search_paths (Target::GetDefaultExecutableSearchPaths());
+    auto error = platform_sp->ResolveExecutable (
+        module_spec, module_sp, !executable_search_paths.IsEmpty() ? &executable_search_paths : nullptr);
     if (error.Fail ())
     {
         StreamString stream;
diff --git a/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.cpp b/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.cpp
new file mode 100644
index 000000000000..56b56ab3a194
--- /dev/null
+++ b/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.cpp
@@ -0,0 +1,102 @@
+//===-- DynamicLoaderWindowsDYLD.cpp --------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "DynamicLoaderWindowsDYLD.h"
+
+#include "lldb/Core/PluginManager.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/Target.h"
+
+#include "llvm/ADT/Triple.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+DynamicLoaderWindowsDYLD::DynamicLoaderWindowsDYLD(Process *process)
+    : DynamicLoader(process)
+{
+
+}
+
+DynamicLoaderWindowsDYLD::~DynamicLoaderWindowsDYLD()
+{
+
+}
+
+void DynamicLoaderWindowsDYLD::Initialize()
+{
+    PluginManager::RegisterPlugin(GetPluginNameStatic(),
+                                  GetPluginDescriptionStatic(),
+                                  CreateInstance);
+}
+
+void DynamicLoaderWindowsDYLD::Terminate()
+{
+
+}
+
+ConstString DynamicLoaderWindowsDYLD::GetPluginNameStatic()
+{
+    static ConstString g_plugin_name("windows-dyld");
+    return g_plugin_name;
+}
+
+const char *DynamicLoaderWindowsDYLD::GetPluginDescriptionStatic()
+{
+    return "Dynamic loader plug-in that watches for shared library "
+           "loads/unloads in Windows processes.";
+}
+
+
+DynamicLoader *DynamicLoaderWindowsDYLD::CreateInstance(Process *process, bool force)
+{
+    bool should_create = force;
+    if (!should_create)
+    {
+        const llvm::Triple &triple_ref = process->GetTarget().GetArchitecture().GetTriple();
+        if (triple_ref.getOS() == llvm::Triple::Win32)
+            should_create = true;
+    }
+
+    if (should_create)
+        return new DynamicLoaderWindowsDYLD (process);
+
+    return nullptr;
+}
+
+void DynamicLoaderWindowsDYLD::DidAttach()
+{
+
+}
+
+void DynamicLoaderWindowsDYLD::DidLaunch()
+{
+
+}
+
+Error DynamicLoaderWindowsDYLD::CanLoadImage()
+{
+    return Error();
+}
+
+ConstString DynamicLoaderWindowsDYLD::GetPluginName()
+{
+    return GetPluginNameStatic();
+}
+
+uint32_t DynamicLoaderWindowsDYLD::GetPluginVersion()
+{
+    return 1;
+}
+
+ThreadPlanSP
+DynamicLoaderWindowsDYLD::GetStepThroughTrampolinePlan(Thread &thread, bool stop)
+{
+    return ThreadPlanSP();
+}
diff --git a/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.h b/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.h
new file mode 100644
index 000000000000..d12b999f4627
--- /dev/null
+++ b/source/Plugins/DynamicLoader/Windows-DYLD/DynamicLoaderWindowsDYLD.h
@@ -0,0 +1,43 @@
+//===-- DynamicLoaderWindowsDYLDh ----------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef liblldb_Plugins_Process_Windows_DynamicLoaderWindowsDYLD_H_
+#define liblldb_Plugins_Process_Windows_DynamicLoaderWindowsDYLD_H_
+
+#include "lldb/lldb-forward.h"
+#include "lldb/Target/DynamicLoader.h"
+
+namespace lldb_private
+{
+
+class DynamicLoaderWindowsDYLD : public DynamicLoader
+{
+  public:
+    DynamicLoaderWindowsDYLD(Process *process);
+    virtual ~DynamicLoaderWindowsDYLD();
+
+    static void Initialize();
+    static void Terminate();
+    static ConstString GetPluginNameStatic();
+    static const char *GetPluginDescriptionStatic();
+
+    static DynamicLoader *CreateInstance(Process *process, bool force);
+
+    void DidAttach () override;
+    void DidLaunch () override;
+    Error CanLoadImage () override;
+    lldb::ThreadPlanSP GetStepThroughTrampolinePlan(Thread &thread, bool stop) override;
+
+    ConstString GetPluginName() override;
+    uint32_t GetPluginVersion() override;
+};
+
+}
+
+#endif
diff --git a/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp b/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
index 7d21b779ebd2..3a3878ef09a1 100644
--- a/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
+++ b/source/Plugins/LanguageRuntime/CPlusPlus/ItaniumABI/ItaniumABILanguageRuntime.cpp
@@ -106,7 +106,7 @@ ItaniumABILanguageRuntime::GetDynamicTypeAndAddress (ValueObject &in_value,
                 Symbol *symbol = sc.symbol;
                 if (symbol != NULL)
                 {
-                    const char *name = symbol->GetMangled().GetDemangledName().AsCString();
+                    const char *name = symbol->GetMangled().GetDemangledName(lldb::eLanguageTypeC_plus_plus).AsCString();
                     if (name && strstr(name, vtable_demangled_prefix) == name)
                     {
                         Log *log (lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_OBJECT));
diff --git a/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp b/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
index f9cec2415382..5fc83f06157c 100644
--- a/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
+++ b/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
@@ -1558,7 +1558,7 @@ ObjectFileELF::GetSegmentDataByIndex(lldb::user_id_t id)
 std::string
 ObjectFileELF::StripLinkerSymbolAnnotations(llvm::StringRef symbol_name) const
 {
-    size_t pos = symbol_name.find("@");
+    size_t pos = symbol_name.find('@');
     return symbol_name.substr(0, pos).str();
 }
 
@@ -1795,7 +1795,16 @@ ObjectFileELF::ParseSymbols (Symtab *symtab,
     static ConstString bss_section_name(".bss");
     static ConstString opd_section_name(".opd");    // For ppc64
 
-    //StreamFile strm(stdout, false);
+    // On Android the oatdata and the oatexec symbols in system@framework@boot.oat covers the full
+    // .text section what causes issues with displaying unusable symbol name to the user and very
+    // slow unwinding speed because the instruction emulation based unwind plans try to emulate all
+    // instructions in these symbols. Don't add these symbols to the symbol list as they have no
+    // use for the debugger and they are causing a lot of trouble.
+    // Filtering can't be restricted to Android because this special object file don't contain the
+    // note section specifying the environment to Android but the custom extension and file name
+    // makes it highly unlikely that this will collide with anything else.
+    bool skip_oatdata_oatexec = m_file.GetFilename() == ConstString("system@framework@boot.oat");
+
     unsigned i;
     for (i = 0; i < num_symbols; ++i)
     {
@@ -1809,7 +1818,10 @@ ObjectFileELF::ParseSymbols (Symtab *symtab,
             (symbol_name == NULL || symbol_name[0] == '\0'))
             continue;
 
-        //symbol.Dump (&strm, i, &strtab_data, section_list);
+        // Skipping oatdata and oatexec sections if it is requested. See details above the
+        // definition of skip_oatdata_oatexec for the reasons.
+        if (skip_oatdata_oatexec && (::strcmp(symbol_name, "oatdata") == 0 || ::strcmp(symbol_name, "oatexec") == 0))
+            continue;
 
         SectionSP symbol_section_sp;
         SymbolType symbol_type = eSymbolTypeInvalid;
@@ -2031,8 +2043,9 @@ ObjectFileELF::ParseSymbols (Symtab *symtab,
             if (! mangled_name.empty())
                 mangled.SetMangledName( ConstString((mangled_name + suffix).str()) );
 
-            llvm::StringRef demangled_name = mangled.GetDemangledName().GetStringRef();
-            if (! demangled_name.empty())
+            ConstString demangled = mangled.GetDemangledName(lldb::eLanguageTypeUnknown);
+            llvm::StringRef demangled_name = demangled.GetStringRef();
+            if (!demangled_name.empty())
                 mangled.SetDemangledName( ConstString((demangled_name + suffix).str()) );
         }
 
diff --git a/source/Plugins/Platform/POSIX/PlatformPOSIX.cpp b/source/Plugins/Platform/POSIX/PlatformPOSIX.cpp
index fe425e02103b..b4f841a16dec 100644
--- a/source/Plugins/Platform/POSIX/PlatformPOSIX.cpp
+++ b/source/Plugins/Platform/POSIX/PlatformPOSIX.cpp
@@ -535,6 +535,14 @@ PlatformPOSIX::CalculateMD5 (const FileSpec& file_spec,
     return false;
 }
 
+const lldb::UnixSignalsSP &
+PlatformPOSIX::GetRemoteUnixSignals() {
+    if (IsRemote() && m_remote_platform_sp)
+        return m_remote_platform_sp->GetRemoteUnixSignals();
+    return Platform::GetRemoteUnixSignals();
+}
+
+
 FileSpec
 PlatformPOSIX::GetRemoteWorkingDirectory()
 {
@@ -785,9 +793,6 @@ PlatformPOSIX::Attach (ProcessAttachInfo &attach_info,
 
             if (process_sp)
             {
-                // Set UnixSignals appropriately.
-                process_sp->SetUnixSignals (Host::GetUnixSignals ());
-
                 auto listener_sp = attach_info.GetHijackListener();
                 if (listener_sp == nullptr)
                 {
diff --git a/source/Plugins/Platform/POSIX/PlatformPOSIX.h b/source/Plugins/Platform/POSIX/PlatformPOSIX.h
index 19a3f0c4eef1..82686dcef6b0 100644
--- a/source/Plugins/Platform/POSIX/PlatformPOSIX.h
+++ b/source/Plugins/Platform/POSIX/PlatformPOSIX.h
@@ -109,6 +109,9 @@ public:
     lldb_private::ArchSpec
     GetRemoteSystemArchitecture () override;
 
+    const lldb::UnixSignalsSP &
+    GetRemoteUnixSignals() override;
+
     size_t
     GetEnvironment (lldb_private::StringList &environment) override;
 
diff --git a/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.cpp b/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.cpp
index df0484c4e69b..b0e75d4f3457 100644
--- a/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.cpp
+++ b/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.cpp
@@ -32,6 +32,8 @@
 
 #include "Utility/UriParser.h"
 
+#include "Plugins/Process/Utility/GDBRemoteSignals.h"
+
 using namespace lldb;
 using namespace lldb_private;
 using namespace lldb_private::platform_gdb_server;
@@ -139,13 +141,14 @@ PlatformRemoteGDBServer::ResolveExecutable (const ModuleSpec &module_spec,
     // Resolve any executable within an apk on Android?
     //Host::ResolveExecutableInBundle (resolved_module_spec.GetFileSpec());
 
-    if (resolved_module_spec.GetFileSpec().Exists())
+    if (resolved_module_spec.GetFileSpec().Exists() ||
+        module_spec.GetUUID().IsValid())
     {
         if (resolved_module_spec.GetArchitecture().IsValid() || resolved_module_spec.GetUUID().IsValid())
         {
             error = ModuleList::GetSharedModule (resolved_module_spec,
                                                  exe_module_sp,
-                                                 NULL,
+                                                 module_search_paths_ptr,
                                                  NULL,
                                                  NULL);
 
@@ -161,7 +164,7 @@ PlatformRemoteGDBServer::ResolveExecutable (const ModuleSpec &module_spec,
         {
             error = ModuleList::GetSharedModule (resolved_module_spec,
                                                  exe_module_sp,
-                                                 NULL,
+                                                 module_search_paths_ptr,
                                                  NULL,
                                                  NULL);
             // Did we find an executable using one of the
@@ -413,6 +416,7 @@ PlatformRemoteGDBServer::DisconnectRemote ()
 {
     Error error;
     m_gdb_client.Disconnect(&error);
+    m_remote_signals_sp.reset();
     return error;
 }
 
@@ -871,6 +875,97 @@ PlatformRemoteGDBServer::RunShellCommand(const char *command,           // Shoul
 
 void
 PlatformRemoteGDBServer::CalculateTrapHandlerSymbolNames ()
-{   
+{
     m_trap_handlers.push_back (ConstString ("_sigtramp"));
 }
+
+const UnixSignalsSP &
+PlatformRemoteGDBServer::GetRemoteUnixSignals()
+{
+    if (!IsConnected())
+        return Platform::GetRemoteUnixSignals();
+
+    if (m_remote_signals_sp)
+        return m_remote_signals_sp;
+
+    // If packet not implemented or JSON failed to parse,
+    // we'll guess the signal set based on the remote architecture.
+    m_remote_signals_sp = UnixSignals::Create(GetRemoteSystemArchitecture());
+
+    const char packet[] = "jSignalsInfo";
+    StringExtractorGDBRemote response;
+    auto result = m_gdb_client.SendPacketAndWaitForResponse(
+            packet, strlen(packet), response, false);
+
+    if (result != decltype(result)::Success ||
+            response.GetResponseType() != response.eResponse)
+        return m_remote_signals_sp;
+
+    auto object_sp = StructuredData::ParseJSON(response.GetStringRef());
+    if (!object_sp || !object_sp->IsValid())
+        return m_remote_signals_sp;
+
+    auto array_sp = object_sp->GetAsArray();
+    if (!array_sp || !array_sp->IsValid())
+        return m_remote_signals_sp;
+
+    auto remote_signals_sp = std::make_shared<lldb_private::GDBRemoteSignals>();
+
+    bool done = array_sp->ForEach(
+        [&remote_signals_sp](StructuredData::Object *object) -> bool
+        {
+            if (!object || !object->IsValid())
+                return false;
+
+            auto dict = object->GetAsDictionary();
+            if (!dict || !dict->IsValid())
+                return false;
+
+            // Signal number and signal name are required.
+            int signo;
+            if (!dict->GetValueForKeyAsInteger("signo", signo))
+                return false;
+
+            std::string name;
+            if (!dict->GetValueForKeyAsString("name", name))
+                return false;
+
+            // We can live without short_name, description, etc.
+            std::string short_name{""};
+            auto object_sp = dict->GetValueForKey("short_name");
+            if (object_sp && object_sp->IsValid())
+                short_name = object_sp->GetStringValue();
+
+            bool suppress{false};
+            object_sp = dict->GetValueForKey("suppress");
+            if (object_sp && object_sp->IsValid())
+                suppress = object_sp->GetBooleanValue();
+
+            bool stop{false};
+            object_sp = dict->GetValueForKey("stop");
+            if (object_sp && object_sp->IsValid())
+                stop = object_sp->GetBooleanValue();
+
+            bool notify{false};
+            object_sp = dict->GetValueForKey("notify");
+            if (object_sp && object_sp->IsValid())
+                notify = object_sp->GetBooleanValue();
+
+            std::string description{""};
+            object_sp = dict->GetValueForKey("description");
+            if (object_sp && object_sp->IsValid())
+                description = object_sp->GetStringValue();
+
+            remote_signals_sp->AddSignal(signo,
+                                         name.c_str(),
+                                         short_name.c_str(),
+                                         suppress, stop, notify,
+                                         description.c_str());
+            return true;
+        });
+
+    if (done)
+        m_remote_signals_sp = std::move(remote_signals_sp);
+
+    return m_remote_signals_sp;
+}
diff --git a/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.h b/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.h
index 1d97b4dbc683..0bf013fdfb68 100644
--- a/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.h
+++ b/source/Plugins/Platform/gdb-server/PlatformRemoteGDBServer.h
@@ -18,6 +18,7 @@
 // Project includes
 #include "lldb/Target/Platform.h"
 #include "../../Process/gdb-remote/GDBRemoteCommunicationClient.h"
+#include "Plugins/Process/Utility/GDBRemoteSignals.h"
 
 namespace lldb_private {
 namespace platform_gdb_server {
@@ -213,12 +214,17 @@ public:
     void
     CalculateTrapHandlerSymbolNames () override;
 
+    const lldb::UnixSignalsSP &
+    GetRemoteUnixSignals() override;
+
 protected:
     process_gdb_remote::GDBRemoteCommunicationClient m_gdb_client;
     std::string m_platform_description; // After we connect we can get a more complete description of what we are connected to
     std::string m_platform_scheme;
     std::string m_platform_hostname;
 
+    lldb::UnixSignalsSP m_remote_signals_sp;
+
     // Launch the lldb-gdbserver on the remote host and return the port it is listening on or 0 on
     // failure. Subclasses should override this method if they want to do extra actions before or
     // after launching the lldb-gdbserver.
diff --git a/source/Plugins/Process/FreeBSD/FreeBSDThread.cpp b/source/Plugins/Process/FreeBSD/FreeBSDThread.cpp
index cce7a1ef28c1..5e46c836beac 100644
--- a/source/Plugins/Process/FreeBSD/FreeBSDThread.cpp
+++ b/source/Plugins/Process/FreeBSD/FreeBSDThread.cpp
@@ -46,7 +46,7 @@ FreeBSDThread::WillResume(lldb::StateType resume_state)
     ProcessSP process_sp(GetProcess());
     ProcessFreeBSD *process = static_cast<ProcessFreeBSD *>(process_sp.get());
     int signo = GetResumeSignal();
-    bool signo_valid = process->GetUnixSignals().SignalIsValid(signo);
+    bool signo_valid = process->GetUnixSignals()->SignalIsValid(signo);
 
     switch (resume_state)
     {
diff --git a/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp b/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
index 28bca0916148..427c66ce3e6b 100644
--- a/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
+++ b/source/Plugins/Process/FreeBSD/ProcessMonitor.cpp
@@ -1297,7 +1297,7 @@ ProcessMonitor::MonitorSignal(ProcessMonitor *monitor,
         if (log)
             log->Printf ("ProcessMonitor::%s() received signal %s with code %s, pid = %d",
                             __FUNCTION__,
-                            monitor->m_process->GetUnixSignals().GetSignalAsCString (signo),
+                            monitor->m_process->GetUnixSignals()->GetSignalAsCString (signo),
                             "SI_USER",
                             info->si_pid);
         if (info->si_pid == getpid())
@@ -1307,7 +1307,7 @@ ProcessMonitor::MonitorSignal(ProcessMonitor *monitor,
     }
 
     if (log)
-        log->Printf ("ProcessMonitor::%s() received signal %s", __FUNCTION__, monitor->m_process->GetUnixSignals().GetSignalAsCString (signo));
+        log->Printf ("ProcessMonitor::%s() received signal %s", __FUNCTION__, monitor->m_process->GetUnixSignals()->GetSignalAsCString (signo));
 
     switch (signo)
     {
@@ -1483,7 +1483,7 @@ ProcessMonitor::Resume(lldb::tid_t unused, uint32_t signo)
     Log *log (ProcessPOSIXLog::GetLogIfAllCategoriesSet (POSIX_LOG_PROCESS));
 
     if (log) {
-        const char *signame = m_process->GetUnixSignals().GetSignalAsCString (signo);
+        const char *signame = m_process->GetUnixSignals()->GetSignalAsCString (signo);
         if (signame == nullptr)
             signame = "<none>";
         log->Printf("ProcessMonitor::%s() resuming pid %"  PRIu64 " with signal %s",
diff --git a/source/Plugins/Process/FreeBSD/ProcessPOSIX.h b/source/Plugins/Process/FreeBSD/ProcessPOSIX.h
index 70694cb9b193..627017c547dc 100644
--- a/source/Plugins/Process/FreeBSD/ProcessPOSIX.h
+++ b/source/Plugins/Process/FreeBSD/ProcessPOSIX.h
@@ -33,7 +33,7 @@ public:
     //------------------------------------------------------------------
     ProcessPOSIX(lldb_private::Target& target,
                  lldb_private::Listener &listener,
-                 lldb_private::UnixSignalsSP &unix_signals_sp);
+                 lldb::UnixSignalsSP &unix_signals_sp);
 
     virtual
     ~ProcessPOSIX();
diff --git a/source/Plugins/Process/Utility/FreeBSDSignals.cpp b/source/Plugins/Process/Utility/FreeBSDSignals.cpp
index f082e143059c..c143d36e87c7 100644
--- a/source/Plugins/Process/Utility/FreeBSDSignals.cpp
+++ b/source/Plugins/Process/Utility/FreeBSDSignals.cpp
@@ -13,6 +13,8 @@
 // Project includes
 #include "FreeBSDSignals.h"
 
+using namespace lldb_private;
+
 FreeBSDSignals::FreeBSDSignals()
     : UnixSignals()
 {
diff --git a/source/Plugins/Process/Utility/FreeBSDSignals.h b/source/Plugins/Process/Utility/FreeBSDSignals.h
index 1e14ccb9fc4d..b715c62c81e9 100644
--- a/source/Plugins/Process/Utility/FreeBSDSignals.h
+++ b/source/Plugins/Process/Utility/FreeBSDSignals.h
@@ -13,16 +13,19 @@
 // Project includes
 #include "lldb/Target/UnixSignals.h"
 
+namespace lldb_private {
+
 /// FreeBSD specific set of Unix signals.
-class FreeBSDSignals
-    : public lldb_private::UnixSignals
+class FreeBSDSignals : public UnixSignals
 {
 public:
     FreeBSDSignals();
 
 private:
     void
-    Reset();
+    Reset() override;
 };
 
+} // namespace lldb_private
+
 #endif // liblldb_FreeBSDSignals_H_
diff --git a/source/Plugins/Process/Utility/GDBRemoteSignals.cpp b/source/Plugins/Process/Utility/GDBRemoteSignals.cpp
new file mode 100644
index 000000000000..4e355c63b3aa
--- /dev/null
+++ b/source/Plugins/Process/Utility/GDBRemoteSignals.cpp
@@ -0,0 +1,32 @@
+//===-- GDBRemoteSignals.cpp ------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// C++ Includes
+// Other libraries and framework includes
+// Project includes
+#include "GDBRemoteSignals.h"
+
+using namespace lldb_private;
+
+GDBRemoteSignals::GDBRemoteSignals()
+    : UnixSignals()
+{
+    Reset();
+}
+
+GDBRemoteSignals::GDBRemoteSignals(const lldb::UnixSignalsSP &rhs)
+    : UnixSignals(*rhs)
+{
+}
+
+void
+GDBRemoteSignals::Reset()
+{
+    m_signals.clear();
+}
diff --git a/source/Plugins/Process/Utility/GDBRemoteSignals.h b/source/Plugins/Process/Utility/GDBRemoteSignals.h
new file mode 100644
index 000000000000..bbb631a14090
--- /dev/null
+++ b/source/Plugins/Process/Utility/GDBRemoteSignals.h
@@ -0,0 +1,36 @@
+//===-- GDBRemoteSignals.h --------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef liblldb_GDBRemoteSignals_H_
+#define liblldb_GDBRemoteSignals_H_
+
+// C Includes
+// C++ Includes
+// Other libraries and framework includes
+// Project includes
+#include "lldb/Target/UnixSignals.h"
+
+namespace lldb_private {
+
+/// Empty set of Unix signals to be filled by PlatformRemoteGDBServer
+class GDBRemoteSignals : public UnixSignals
+{
+public:
+    GDBRemoteSignals();
+
+    GDBRemoteSignals(const lldb::UnixSignalsSP &rhs);
+
+private:
+    void
+    Reset() override;
+};
+
+} // namespace lldb_private
+
+#endif // liblldb_GDBRemoteSignals_H_
diff --git a/source/Plugins/Process/Utility/LinuxSignals.cpp b/source/Plugins/Process/Utility/LinuxSignals.cpp
index 0680d268233c..cd1fc8165eb9 100644
--- a/source/Plugins/Process/Utility/LinuxSignals.cpp
+++ b/source/Plugins/Process/Utility/LinuxSignals.cpp
@@ -12,7 +12,7 @@
 // Project includes
 #include "LinuxSignals.h"
 
-using namespace lldb_private::process_linux;
+using namespace lldb_private;
 
 LinuxSignals::LinuxSignals()
     : UnixSignals()
diff --git a/source/Plugins/Process/Utility/LinuxSignals.h b/source/Plugins/Process/Utility/LinuxSignals.h
index 5102bcb95e74..dd9062f040a2 100644
--- a/source/Plugins/Process/Utility/LinuxSignals.h
+++ b/source/Plugins/Process/Utility/LinuxSignals.h
@@ -17,21 +17,18 @@
 #include "lldb/Target/UnixSignals.h"
 
 namespace lldb_private {
-namespace process_linux {
 
-    /// Linux specific set of Unix signals.
-    class LinuxSignals
-        : public lldb_private::UnixSignals
-    {
-    public:
-        LinuxSignals();
+/// Linux specific set of Unix signals.
+class LinuxSignals : public UnixSignals
+{
+public:
+    LinuxSignals();
 
-    private:
-        void
-        Reset();
-    };
+private:
+    void
+    Reset() override;
+};
 
 } // namespace lldb_private
-} // namespace process_linux
 
-#endif
+#endif // liblldb_LinuxSignals_H_
diff --git a/source/Plugins/Process/Utility/MipsLinuxSignals.cpp b/source/Plugins/Process/Utility/MipsLinuxSignals.cpp
index e4e654626eaa..1dc0be81c0ae 100644
--- a/source/Plugins/Process/Utility/MipsLinuxSignals.cpp
+++ b/source/Plugins/Process/Utility/MipsLinuxSignals.cpp
@@ -12,7 +12,7 @@
 // Project includes
 #include "MipsLinuxSignals.h"
 
-using namespace lldb_private::process_linux;
+using namespace lldb_private;
 
 MipsLinuxSignals::MipsLinuxSignals()
     : UnixSignals()
diff --git a/source/Plugins/Process/Utility/MipsLinuxSignals.h b/source/Plugins/Process/Utility/MipsLinuxSignals.h
index 2e603fbbdf3c..a5041b50eea3 100644
--- a/source/Plugins/Process/Utility/MipsLinuxSignals.h
+++ b/source/Plugins/Process/Utility/MipsLinuxSignals.h
@@ -17,21 +17,18 @@
 #include "lldb/Target/UnixSignals.h"
 
 namespace lldb_private {
-namespace process_linux {
 
-    /// Linux specific set of Unix signals.
-    class MipsLinuxSignals
-        : public lldb_private::UnixSignals
-    {
-    public:
-        MipsLinuxSignals();
+/// Linux specific set of Unix signals.
+class MipsLinuxSignals : public UnixSignals
+{
+public:
+    MipsLinuxSignals();
 
-    private:
-        void
-        Reset();
-    };
+private:
+    void
+    Reset() override;
+};
 
 } // namespace lldb_private
-} // namespace process_linux
 
-#endif
+#endif // liblldb_MipsLinuxSignals_H_
diff --git a/source/Plugins/Process/Utility/UnwindLLDB.cpp b/source/Plugins/Process/Utility/UnwindLLDB.cpp
index 02d3ecd7b3c5..1cdae9011673 100644
--- a/source/Plugins/Process/Utility/UnwindLLDB.cpp
+++ b/source/Plugins/Process/Utility/UnwindLLDB.cpp
@@ -120,29 +120,28 @@ unwind_done:
     return false;
 }
 
-// For adding a non-zero stack frame to m_frames.
-bool
-UnwindLLDB::AddOneMoreFrame (ABI *abi)
+UnwindLLDB::CursorSP
+UnwindLLDB::GetOneMoreFrame (ABI* abi)
 {
+    assert (m_frames.size() != 0 && "Get one more frame called with empty frame list");
+
     // If we've already gotten to the end of the stack, don't bother to try again...
     if (m_unwind_complete)
-        return false;
+        return nullptr;
         
     Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND));
-    CursorSP cursor_sp(new Cursor ());
 
-    // Frame zero is a little different
-    if (m_frames.size() == 0)
-        return false;
+    CursorSP prev_frame = m_frames.back();
+    uint32_t cur_idx = m_frames.size();
 
-    uint32_t cur_idx = m_frames.size ();
+    CursorSP cursor_sp(new Cursor ());
     RegisterContextLLDBSP reg_ctx_sp(new RegisterContextLLDB (m_thread, 
-                                                              m_frames[cur_idx - 1]->reg_ctx_lldb_sp, 
+                                                              prev_frame->reg_ctx_lldb_sp, 
                                                               cursor_sp->sctx, 
                                                               cur_idx, 
                                                               *this));
 
-    // We want to detect an unwind that cycles erronously and stop backtracing.
+    // We want to detect an unwind that cycles erroneously and stop backtracing.
     // Don't want this maximum unwind limit to be too low -- if you have a backtrace
     // with an "infinitely recursing" bug, it will crash when the stack blows out
     // and the first 35,000 frames are uninteresting - it's the top most 5 frames that
@@ -154,21 +153,20 @@ UnwindLLDB::AddOneMoreFrame (ABI *abi)
         if (log)
             log->Printf ("%*sFrame %d unwound too many frames, assuming unwind has gone astray, stopping.", 
                          cur_idx < 100 ? cur_idx : 100, "", cur_idx);
-        goto unwind_done;
+        return nullptr;
     }
 
     if (reg_ctx_sp.get() == NULL)
     {
         // If the RegisterContextLLDB has a fallback UnwindPlan, it will switch to that and return
         // true.  Subsequent calls to TryFallbackUnwindPlan() will return false.
-        if (m_frames[cur_idx - 1]->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
-        {
-            return AddOneMoreFrame (abi);
-        }
+        if (prev_frame->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
+            return GetOneMoreFrame (abi);
+
         if (log)
             log->Printf ("%*sFrame %d did not get a RegisterContext, stopping.",
                          cur_idx < 100 ? cur_idx : 100, "", cur_idx);
-        goto unwind_done;
+        return nullptr;
     }
 
     if (!reg_ctx_sp->IsValid())
@@ -176,31 +174,25 @@ UnwindLLDB::AddOneMoreFrame (ABI *abi)
         // We failed to get a valid RegisterContext.
         // See if the regctx below this on the stack has a fallback unwind plan it can use.
         // Subsequent calls to TryFallbackUnwindPlan() will return false.
-        if (m_frames[cur_idx - 1]->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
-        {
-            return AddOneMoreFrame (abi);
-        }
+        if (prev_frame->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
+            return GetOneMoreFrame (abi);
+
         if (log)
-        {
             log->Printf("%*sFrame %d invalid RegisterContext for this frame, stopping stack walk", 
                         cur_idx < 100 ? cur_idx : 100, "", cur_idx);
-        }
-        goto unwind_done;
+        return nullptr;
     }
     if (!reg_ctx_sp->GetCFA (cursor_sp->cfa))
     {
         // If the RegisterContextLLDB has a fallback UnwindPlan, it will switch to that and return
         // true.  Subsequent calls to TryFallbackUnwindPlan() will return false.
-        if (m_frames[cur_idx - 1]->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
-        {
-            return AddOneMoreFrame (abi);
-        }
+        if (prev_frame->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
+            return GetOneMoreFrame (abi);
+
         if (log)
-        {
             log->Printf("%*sFrame %d did not get CFA for this frame, stopping stack walk",
                         cur_idx < 100 ? cur_idx : 100, "", cur_idx);
-        }
-        goto unwind_done;
+        return nullptr;
     }
     if (abi && !abi->CallFrameAddressIsValid(cursor_sp->cfa))
     {
@@ -219,24 +211,19 @@ UnwindLLDB::AddOneMoreFrame (ABI *abi)
                 || reg_ctx_sp->GetCFA (cursor_sp->cfa) == false
                 || abi->CallFrameAddressIsValid(cursor_sp->cfa) == false)
             {
-                if (m_frames[cur_idx - 1]->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
-                {
-                    return AddOneMoreFrame (abi);
-                }
+                if (prev_frame->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
+                    return GetOneMoreFrame (abi);
+
                 if (log)
-                {
                     log->Printf("%*sFrame %d did not get a valid CFA for this frame, stopping stack walk",
                                 cur_idx < 100 ? cur_idx : 100, "", cur_idx);
-                }
-                goto unwind_done;
+                return nullptr;
             }
             else
             {
                 if (log)
-                {
                     log->Printf("%*sFrame %d had a bad CFA value but we switched the UnwindPlan being used and got one that looks more realistic.",
                                 cur_idx < 100 ? cur_idx : 100, "", cur_idx);
-                }
             }
         }
     }
@@ -244,54 +231,103 @@ UnwindLLDB::AddOneMoreFrame (ABI *abi)
     {
         // If the RegisterContextLLDB has a fallback UnwindPlan, it will switch to that and return
         // true.  Subsequent calls to TryFallbackUnwindPlan() will return false.
-        if (m_frames[cur_idx - 1]->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
-        {
-            return AddOneMoreFrame (abi);
-        }
+        if (prev_frame->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
+            return GetOneMoreFrame (abi);
+
         if (log)
-        {
             log->Printf("%*sFrame %d did not get PC for this frame, stopping stack walk",
                         cur_idx < 100 ? cur_idx : 100, "", cur_idx);
-        }
-        goto unwind_done;
+        return nullptr;
     }
     if (abi && !abi->CodeAddressIsValid (cursor_sp->start_pc))
     {
         // If the RegisterContextLLDB has a fallback UnwindPlan, it will switch to that and return
         // true.  Subsequent calls to TryFallbackUnwindPlan() will return false.
-        if (m_frames[cur_idx - 1]->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
-        {
-            return AddOneMoreFrame (abi);
-        }
+        if (prev_frame->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
+            return GetOneMoreFrame (abi);
+
         if (log)
-        {
             log->Printf("%*sFrame %d did not get a valid PC, stopping stack walk",
                         cur_idx < 100 ? cur_idx : 100, "", cur_idx);
-        }
-        goto unwind_done;
+        return nullptr;
     }
-    if (!m_frames.empty())
+    // Infinite loop where the current cursor is the same as the previous one...
+    if (prev_frame->start_pc == cursor_sp->start_pc && prev_frame->cfa == cursor_sp->cfa)
     {
-        // Infinite loop where the current cursor is the same as the previous one...
-        if (m_frames.back()->start_pc == cursor_sp->start_pc && m_frames.back()->cfa == cursor_sp->cfa)
-        {
-            if (log)
-                log->Printf ("th%d pc of this frame is the same as the previous frame and CFAs for both frames are identical -- stopping unwind", m_thread.GetIndexID());
-            goto unwind_done; 
-        }
+        if (log)
+            log->Printf ("th%d pc of this frame is the same as the previous frame and CFAs for both frames are identical -- stopping unwind", m_thread.GetIndexID());
+        return nullptr;
     }
 
     cursor_sp->reg_ctx_lldb_sp = reg_ctx_sp;
-    m_frames.push_back (cursor_sp);
-    return true;
-    
-unwind_done:
-    if (log)
+    return cursor_sp;
+}
+
+bool
+UnwindLLDB::AddOneMoreFrame (ABI *abi)
+{
+    Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND));
+
+    // Frame zero is a little different
+    if (m_frames.empty())
+        return false;
+
+    // If we've already gotten to the end of the stack, don't bother to try again...
+    if (m_unwind_complete)
+        return false;
+
+    CursorSP new_frame = m_candidate_frame;
+    if (new_frame == nullptr)
+        new_frame = GetOneMoreFrame(abi);
+
+    if (new_frame == nullptr)
     {
-        log->Printf ("th%d Unwind of this thread is complete.", m_thread.GetIndexID());
+        if (log)
+            log->Printf ("th%d Unwind of this thread is complete.", m_thread.GetIndexID());
+        m_unwind_complete = true;
+        return false;
     }
-    m_unwind_complete = true;
-    return false;
+
+    m_frames.push_back(new_frame);
+
+    // If we can get one more frame further then accept that we get back a correct frame.
+    m_candidate_frame = GetOneMoreFrame(abi);
+    if (m_candidate_frame)
+        return true;
+
+    // We can't go further from the frame returned by GetOneMore frame. Lets try to get a
+    // different frame with using the fallback unwind plan.
+    if (!m_frames[m_frames.size() - 2]->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
+    {
+        // We don't have a valid fallback unwind plan. Accept the frame as it is. This is a
+        // valid situation when we are at the bottom of the stack.
+        return true;
+    }
+
+    // Remove the possibly incorrect frame from the frame list and try to add a different one with
+    // the newly selected fallback unwind plan.
+    m_frames.pop_back();
+    CursorSP new_frame_v2 = GetOneMoreFrame(abi);
+    if (new_frame_v2 == nullptr)
+    {
+        // We haven't got a new frame from the fallback unwind plan. Accept the frame from the
+        // original unwind plan. This is a valid situation when we are at the bottom of the stack.
+        m_frames.push_back(new_frame);
+        return true;
+    }
+
+    // Push the new frame to the list and try to continue from this frame. If we can get a new frame
+    // then accept it as the correct one.
+    m_frames.push_back(new_frame_v2);
+    m_candidate_frame = GetOneMoreFrame(abi);
+    if (m_candidate_frame)
+        return true;
+
+    // The new frame isn't helped in unwinding. Fall back to the original one as the default unwind
+    // plan is usually more reliable then the fallback one.
+    m_frames.pop_back();
+    m_frames.push_back(new_frame);
+    return true;
 }
 
 bool
diff --git a/source/Plugins/Process/Utility/UnwindLLDB.h b/source/Plugins/Process/Utility/UnwindLLDB.h
index 35d85e2e3d26..ce897cd82423 100644
--- a/source/Plugins/Process/Utility/UnwindLLDB.h
+++ b/source/Plugins/Process/Utility/UnwindLLDB.h
@@ -65,6 +65,7 @@ protected:
     DoClear()
     {
         m_frames.clear();
+        m_candidate_frame.reset();
         m_unwind_complete = false;
     }
 
@@ -126,14 +127,21 @@ private:
 
     typedef std::shared_ptr<Cursor> CursorSP;
     std::vector<CursorSP> m_frames;
+    CursorSP m_candidate_frame;
     bool m_unwind_complete; // If this is true, we've enumerated all the frames in the stack, and m_frames.size() is the 
                             // number of frames, etc.  Otherwise we've only gone as far as directly asked, and m_frames.size()
                             // is how far we've currently gone.
  
     std::vector<ConstString> m_user_supplied_trap_handler_functions;
 
-    bool AddOneMoreFrame (ABI *abi);
-    bool AddFirstFrame ();
+    CursorSP
+    GetOneMoreFrame (ABI* abi);
+
+    bool
+    AddOneMoreFrame (ABI *abi);
+
+    bool
+    AddFirstFrame ();
 
     //------------------------------------------------------------------
     // For UnwindLLDB only
diff --git a/source/Plugins/Process/elf-core/ProcessElfCore.cpp b/source/Plugins/Process/elf-core/ProcessElfCore.cpp
index 2fff36dd4ee5..bf5cad8e39c5 100644
--- a/source/Plugins/Process/elf-core/ProcessElfCore.cpp
+++ b/source/Plugins/Process/elf-core/ProcessElfCore.cpp
@@ -29,8 +29,6 @@
 
 #include "Plugins/ObjectFile/ELF/ObjectFileELF.h"
 #include "Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.h"
-#include "Plugins/Process/Utility/FreeBSDSignals.h"
-#include "Plugins/Process/Utility/LinuxSignals.h"
 
 // Project includes
 #include "ProcessElfCore.h"
@@ -237,23 +235,7 @@ ProcessElfCore::DoLoadCore ()
     if (arch.IsValid())
         m_target.SetArchitecture(arch);
 
-    switch (m_os)
-    {
-        case llvm::Triple::FreeBSD:
-        {
-            static UnixSignalsSP s_freebsd_signals_sp(new FreeBSDSignals ());
-            SetUnixSignals(s_freebsd_signals_sp);
-            break;
-        }
-        case llvm::Triple::Linux:
-        {
-            static UnixSignalsSP s_linux_signals_sp(new process_linux::LinuxSignals ());
-            SetUnixSignals(s_linux_signals_sp);
-            break;
-        }
-        default:
-            break;
-    }
+    SetUnixSignals(UnixSignals::Create(GetArchitecture()));
 
     return error;
 }
@@ -370,7 +352,7 @@ ProcessElfCore::Clear()
     m_thread_list.Clear();
     m_os = llvm::Triple::UnknownOS;
 
-    static UnixSignalsSP s_default_unix_signals_sp(new UnixSignals());
+    static const auto s_default_unix_signals_sp = std::make_shared<UnixSignals>();
     SetUnixSignals(s_default_unix_signals_sp);
 }
 
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp b/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
index 1af3947a75f3..9c263c8c4087 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunication.cpp
@@ -564,8 +564,12 @@ GDBRemoteCommunication::DecompressPacket ()
         return true;
 
     size_t pkt_size = m_bytes.size();
-    if (pkt_size < 6)
+
+    // Smallest possible compressed packet is $N#00 - an uncompressed empty reply, most commonly indicating
+    // an unsupported packet.  Anything less than 5 characters, it's definitely not a compressed packet.
+    if (pkt_size < 5)
         return true;
+
     if (m_bytes[0] != '$' && m_bytes[0] != '%')
         return true;
     if (m_bytes[1] != 'C' && m_bytes[1] != 'N')
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
index ae0a2f5e66c5..2a253c5a99e8 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
@@ -87,6 +87,7 @@ GDBRemoteCommunicationClient::GDBRemoteCommunicationClient() :
     m_supports_qXfer_features_read (eLazyBoolCalculate),
     m_supports_augmented_libraries_svr4_read (eLazyBoolCalculate),
     m_supports_jThreadExtendedInfo (eLazyBoolCalculate),
+    m_supports_jLoadedDynamicLibrariesInfos (eLazyBoolCalculate),
     m_supports_qProcessInfoPID (true),
     m_supports_qfProcessInfo (true),
     m_supports_qUserName (true),
@@ -654,6 +655,24 @@ GDBRemoteCommunicationClient::GetThreadExtendedInfoSupported ()
 }
 
 bool
+GDBRemoteCommunicationClient::GetLoadedDynamicLibrariesInfosSupported ()
+{
+    if (m_supports_jLoadedDynamicLibrariesInfos == eLazyBoolCalculate)
+    {
+        StringExtractorGDBRemote response;
+        m_supports_jLoadedDynamicLibrariesInfos = eLazyBoolNo;
+        if (SendPacketAndWaitForResponse("jGetLoadedDynamicLibrariesInfos:", response, false) == PacketResult::Success)
+        {
+            if (response.IsOKResponse())
+            {
+                m_supports_jLoadedDynamicLibrariesInfos = eLazyBoolYes;
+            }
+        }
+    }
+    return m_supports_jLoadedDynamicLibrariesInfos;
+}
+
+bool
 GDBRemoteCommunicationClient::GetxPacketSupported ()
 {
     if (m_supports_x == eLazyBoolCalculate)
@@ -1037,8 +1056,8 @@ GDBRemoteCommunicationClient::SendContinuePacketAndWaitForResponse
     // may change if we are interrupted and we continue after an async packet...
     std::string continue_packet(payload, packet_length);
 
-    const auto sigstop_signo = process->GetUnixSignals().GetSignalNumberFromName("SIGSTOP");
-    const auto sigint_signo = process->GetUnixSignals().GetSignalNumberFromName("SIGINT");
+    const auto sigstop_signo = process->GetUnixSignals()->GetSignalNumberFromName("SIGSTOP");
+    const auto sigint_signo = process->GetUnixSignals()->GetSignalNumberFromName("SIGINT");
 
     bool got_async_packet = false;
     
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
index 65a2981018ea..deb41b066b45 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
@@ -550,6 +550,9 @@ public:
     GetThreadExtendedInfoSupported();
 
     bool
+    GetLoadedDynamicLibrariesInfosSupported();
+
+    bool
     GetModuleInfo (const FileSpec& module_file_spec,
                    const ArchSpec& arch_spec,
                    ModuleSpec &module_spec);
@@ -614,6 +617,7 @@ protected:
     LazyBool m_supports_qXfer_features_read;
     LazyBool m_supports_augmented_libraries_svr4_read;
     LazyBool m_supports_jThreadExtendedInfo;
+    LazyBool m_supports_jLoadedDynamicLibrariesInfos;
 
     bool
         m_supports_qProcessInfoPID:1,
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
index 13ce9b2dc5c3..4ee66b84d474 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.cpp
@@ -132,7 +132,7 @@ GDBRemoteCommunicationServer::SendOKResponse ()
 }
 
 bool
-GDBRemoteCommunicationServer::HandshakeWithClient(Error *error_ptr)
+GDBRemoteCommunicationServer::HandshakeWithClient()
 {
     return GetAck() == PacketResult::Success;
 }
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.h b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.h
index 992c6dffaf54..44c0f6a32f5b 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.h
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServer.h
@@ -54,7 +54,7 @@ public:
     // After connecting, do a little handshake with the client to make sure
     // we are at least communicating
     bool
-    HandshakeWithClient (Error *error_ptr);
+    HandshakeWithClient ();
 
 protected:
     std::map<StringExtractorGDBRemote::ServerPacketType, PacketHandler> m_packet_handlers;
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
index e8955ddbd6e4..c4523252f190 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp
@@ -75,10 +75,11 @@ namespace
 // GDBRemoteCommunicationServerLLGS constructor
 //----------------------------------------------------------------------
 GDBRemoteCommunicationServerLLGS::GDBRemoteCommunicationServerLLGS(
-        const lldb::PlatformSP& platform_sp) :
+        const lldb::PlatformSP& platform_sp,
+        MainLoop &mainloop) :
     GDBRemoteCommunicationServerCommon ("gdb-remote.server", "gdb-remote.server.rx_packet"),
     m_platform_sp (platform_sp),
-    m_async_thread (LLDB_INVALID_HOST_THREAD),
+    m_mainloop (mainloop),
     m_current_tid (LLDB_INVALID_THREAD_ID),
     m_continue_tid (LLDB_INVALID_THREAD_ID),
     m_debugged_process_mutex (Mutex::eMutexTypeRecursive),
@@ -88,7 +89,8 @@ GDBRemoteCommunicationServerLLGS::GDBRemoteCommunicationServerLLGS(
     m_active_auxv_buffer_sp (),
     m_saved_registers_mutex (),
     m_saved_registers_map (),
-    m_next_saved_registers_id (1)
+    m_next_saved_registers_id (1),
+    m_handshake_completed (false)
 {
     assert(platform_sp);
     RegisterPacketHandlers();
@@ -218,7 +220,7 @@ GDBRemoteCommunicationServerLLGS::LaunchProcess ()
     {
         Mutex::Locker locker (m_debugged_process_mutex);
         assert (!m_debugged_process_sp && "lldb-gdbserver creating debugged process but one already exists");
-        error = m_platform_sp->LaunchNativeProcess (
+        error = NativeProcessProtocol::Launch(
             m_process_launch_info,
             *this,
             m_debugged_process_sp);
@@ -306,7 +308,7 @@ GDBRemoteCommunicationServerLLGS::AttachToProcess (lldb::pid_t pid)
         }
 
         // Try to attach.
-        error = m_platform_sp->AttachNativeProcess (pid, *this, m_debugged_process_sp);
+        error = NativeProcessProtocol::Attach(pid, *this, m_debugged_process_sp);
         if (!error.Success ())
         {
             fprintf (stderr, "%s: failed to attach to process %" PRIu64 ": %s", __FUNCTION__, pid, error.AsCString ());
@@ -782,6 +784,58 @@ GDBRemoteCommunicationServerLLGS::DidExec (NativeProcessProtocol *process)
     ClearProcessSpecificData ();
 }
 
+void
+GDBRemoteCommunicationServerLLGS::DataAvailableCallback ()
+{
+    Log *log (GetLogIfAnyCategoriesSet(GDBR_LOG_COMM));
+
+    if (! m_handshake_completed)
+    {
+        if (! HandshakeWithClient())
+        {
+            if(log)
+                log->Printf("GDBRemoteCommunicationServerLLGS::%s handshake with client failed, exiting",
+                        __FUNCTION__);
+            m_read_handle_up.reset();
+            m_mainloop.RequestTermination();
+            return;
+        }
+        m_handshake_completed = true;
+    }
+
+    bool interrupt = false;
+    bool done = false;
+    Error error;
+    while (true)
+    {
+        const PacketResult result = GetPacketAndSendResponse (0, error, interrupt, done);
+        if (result == PacketResult::ErrorReplyTimeout)
+            break; // No more packets in the queue
+
+        if ((result != PacketResult::Success))
+        {
+            if(log)
+                log->Printf("GDBRemoteCommunicationServerLLGS::%s processing a packet failed: %s",
+                        __FUNCTION__, error.AsCString());
+            m_read_handle_up.reset();
+            m_mainloop.RequestTermination();
+            break;
+        }
+    }
+}
+
+Error
+GDBRemoteCommunicationServerLLGS::InitializeConnection (std::unique_ptr<Connection> &&connection)
+{
+    IOObjectSP read_object_sp = connection->GetReadObject();
+    GDBRemoteCommunicationServer::SetConnection(connection.release());
+
+    Error error;
+    m_read_handle_up = m_mainloop.RegisterReadObject(read_object_sp,
+            [this] (MainLoopBase &) { DataAvailableCallback(); }, error);
+    return error;
+}
+
 GDBRemoteCommunication::PacketResult
 GDBRemoteCommunicationServerLLGS::SendONotification (const char *buffer, uint32_t len)
 {
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h
index 1eda0b052bb7..29f3fdebcfb0 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.h
@@ -19,6 +19,7 @@
 #include "lldb/Core/Communication.h"
 #include "lldb/Host/Mutex.h"
 #include "lldb/Host/common/NativeProcessProtocol.h"
+#include "lldb/Host/MainLoop.h"
 
 // Project includes
 #include "GDBRemoteCommunicationServerCommon.h"
@@ -26,6 +27,7 @@
 class StringExtractorGDBRemote;
 
 namespace lldb_private {
+
 namespace process_gdb_remote {
 
 class ProcessGDBRemote;
@@ -38,7 +40,7 @@ public:
     //------------------------------------------------------------------
     // Constructors and Destructors
     //------------------------------------------------------------------
-    GDBRemoteCommunicationServerLLGS(const lldb::PlatformSP& platform_sp);
+    GDBRemoteCommunicationServerLLGS(const lldb::PlatformSP& platform_sp, MainLoop &mainloop);
 
     virtual
     ~GDBRemoteCommunicationServerLLGS();
@@ -111,9 +113,13 @@ public:
     void
     DidExec (NativeProcessProtocol *process) override;
 
+    Error
+    InitializeConnection (std::unique_ptr<Connection> &&connection);
+
 protected:
     lldb::PlatformSP m_platform_sp;
-    lldb::thread_t m_async_thread;
+    MainLoop &m_mainloop;
+    MainLoop::ReadHandleUP m_read_handle_up;
     lldb::tid_t m_current_tid;
     lldb::tid_t m_continue_tid;
     Mutex m_debugged_process_mutex;
@@ -124,6 +130,7 @@ protected:
     Mutex m_saved_registers_mutex;
     std::unordered_map<uint32_t, lldb::DataBufferSP> m_saved_registers_map;
     uint32_t m_next_saved_registers_id;
+    bool m_handshake_completed : 1;
 
     PacketResult
     SendONotification (const char *buffer, uint32_t len);
@@ -295,6 +302,9 @@ private:
     void
     RegisterPacketHandlers ();
 
+    void
+    DataAvailableCallback ();
+
     //------------------------------------------------------------------
     // For GDBRemoteCommunicationServerLLGS only
     //------------------------------------------------------------------
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.cpp b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.cpp
index f5e5d76f2e6f..1205049db3fb 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.cpp
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.cpp
@@ -19,6 +19,7 @@
 // Other libraries and framework includes
 #include "lldb/Core/Log.h"
 #include "lldb/Core/StreamString.h"
+#include "lldb/Core/StructuredData.h"
 #include "lldb/Host/Config.h"
 #include "lldb/Host/ConnectionFileDescriptor.h"
 #include "lldb/Host/Host.h"
@@ -26,6 +27,7 @@
 #include "lldb/Target/FileAction.h"
 #include "lldb/Target/Platform.h"
 #include "lldb/Target/Process.h"
+#include "lldb/Target/UnixSignals.h"
 
 // Project includes
 #include "Utility/StringExtractorGDBRemote.h"
@@ -54,6 +56,8 @@ GDBRemoteCommunicationServerPlatform::GDBRemoteCommunicationServerPlatform() :
                                   &GDBRemoteCommunicationServerPlatform::Handle_qProcessInfo);
     RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_QSetWorkingDir,
                                   &GDBRemoteCommunicationServerPlatform::Handle_QSetWorkingDir);
+    RegisterMemberFunctionHandler(StringExtractorGDBRemote::eServerPacketType_jSignalsInfo,
+                                  &GDBRemoteCommunicationServerPlatform::Handle_jSignalsInfo);
 
     RegisterPacketHandler(StringExtractorGDBRemote::eServerPacketType_interrupt,
                           [this](StringExtractorGDBRemote packet,
@@ -251,6 +255,35 @@ GDBRemoteCommunicationServerPlatform::Handle_qC (StringExtractorGDBRemote &packe
     return SendPacketNoLock (response.GetData(), response.GetSize());
 }
 
+GDBRemoteCommunication::PacketResult
+GDBRemoteCommunicationServerPlatform::Handle_jSignalsInfo(StringExtractorGDBRemote &packet)
+{
+    StructuredData::Array signal_array;
+
+    const auto &signals = Host::GetUnixSignals();
+    for (auto signo = signals->GetFirstSignalNumber();
+         signo != LLDB_INVALID_SIGNAL_NUMBER;
+         signo = signals->GetNextSignalNumber(signo))
+    {
+        auto dictionary = std::make_shared<StructuredData::Dictionary>();
+
+        dictionary->AddIntegerItem("signo", signo);
+        dictionary->AddStringItem("name", signals->GetSignalAsCString(signo));
+
+        bool suppress, stop, notify;
+        signals->GetSignalInfo(signo, suppress, stop, notify);
+        dictionary->AddBooleanItem("suppress", suppress);
+        dictionary->AddBooleanItem("stop", stop);
+        dictionary->AddBooleanItem("notify", notify);
+
+        signal_array.Push(dictionary);
+    }
+
+    StreamString response;
+    signal_array.Dump(response);
+    return SendPacketNoLock(response.GetData(), response.GetSize());
+}
+
 bool
 GDBRemoteCommunicationServerPlatform::DebugserverProcessReaped (lldb::pid_t pid)
 {
diff --git a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.h b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.h
index 4124b0424f5d..5c011371a3eb 100644
--- a/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.h
+++ b/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerPlatform.h
@@ -79,6 +79,9 @@ protected:
     PacketResult
     Handle_qC (StringExtractorGDBRemote &packet);
 
+    PacketResult
+    Handle_jSignalsInfo(StringExtractorGDBRemote &packet);
+
 private:
     bool
     DebugserverProcessReaped (lldb::pid_t pid);
diff --git a/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp b/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
index 5cb4da514a7f..0bcc8ca4e5e3 100644
--- a/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ b/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -65,10 +65,8 @@
 
 // Project includes
 #include "lldb/Host/Host.h"
-#include "Plugins/Process/Utility/FreeBSDSignals.h"
+#include "Plugins/Process/Utility/GDBRemoteSignals.h"
 #include "Plugins/Process/Utility/InferiorCallPOSIX.h"
-#include "Plugins/Process/Utility/LinuxSignals.h"
-#include "Plugins/Process/Utility/MipsLinuxSignals.h"
 #include "Plugins/Process/Utility/StopInfoMachException.h"
 #include "Plugins/Platform/MacOSX/PlatformRemoteiOS.h"
 #include "Utility/StringExtractorGDBRemote.h"
@@ -823,41 +821,8 @@ ProcessGDBRemote::DoConnectRemote (Stream *strm, const char *remote_url)
     if (log)
         log->Printf ("ProcessGDBRemote::%s pid %" PRIu64 ": normalized target architecture triple: %s", __FUNCTION__, GetID (), GetTarget ().GetArchitecture ().GetTriple ().getTriple ().c_str ());
 
-    // Set the Unix signals properly for the target.
-    // FIXME Add a gdb-remote packet to discover dynamically.
-    if (error.Success ())
-    {
-        const ArchSpec arch_spec = m_gdb_comm.GetHostArchitecture();
-        if (arch_spec.IsValid ())
-        {
-            if (log)
-                log->Printf ("ProcessGDBRemote::%s pid %" PRIu64 ": determining unix signals type based on architecture %s, triple %s", __FUNCTION__, GetID (), arch_spec.GetArchitectureName () ? arch_spec.GetArchitectureName () : "<null>", arch_spec.GetTriple ().getTriple ().c_str ());
-
-            switch (arch_spec.GetTriple ().getOS ())
-            {
-            case llvm::Triple::Linux:
-                if (arch_spec.GetTriple ().getArch () == llvm::Triple::mips64 || arch_spec.GetTriple ().getArch () == llvm::Triple::mips64el)
-                    SetUnixSignals (UnixSignalsSP (new process_linux::MipsLinuxSignals ()));
-                else
-                    SetUnixSignals (UnixSignalsSP (new process_linux::LinuxSignals ()));
-                if (log)
-                    log->Printf ("ProcessGDBRemote::%s using Linux unix signals type for pid %" PRIu64, __FUNCTION__, GetID ());
-                break;
-            case llvm::Triple::OpenBSD:
-            case llvm::Triple::FreeBSD:
-            case llvm::Triple::NetBSD:
-                SetUnixSignals (UnixSignalsSP (new FreeBSDSignals ()));
-                if (log)
-                    log->Printf ("ProcessGDBRemote::%s using *BSD unix signals type for pid %" PRIu64, __FUNCTION__, GetID ());
-                break;
-            default:
-                SetUnixSignals (UnixSignalsSP (new UnixSignals ()));
-                if (log)
-                    log->Printf ("ProcessGDBRemote::%s using generic unix signals type for pid %" PRIu64, __FUNCTION__, GetID ());
-                break;
-            }
-        }
-    }
+    if (error.Success())
+        SetUnixSignals(std::make_shared<GDBRemoteSignals>(GetTarget().GetPlatform()->GetUnixSignals()));
 
     return error;
 }
@@ -3524,7 +3489,7 @@ ProcessGDBRemote::MonitorDebugserverProcess
                 char error_str[1024];
                 if (signo)
                 {
-                    const char *signal_cstr = process->GetUnixSignals().GetSignalAsCString (signo);
+                    const char *signal_cstr = process->GetUnixSignals()->GetSignalAsCString(signo);
                     if (signal_cstr)
                         ::snprintf (error_str, sizeof (error_str), DEBUGSERVER_BASENAME " died with signal %s", signal_cstr);
                     else
@@ -3985,6 +3950,44 @@ ProcessGDBRemote::GetExtendedInfoForThread (lldb::tid_t tid)
             {
                 if (!response.Empty())
                 {
+                    object_sp = StructuredData::ParseJSON (response.GetStringRef());
+                }
+            }
+        }
+    }
+    return object_sp;
+}
+
+StructuredData::ObjectSP
+ProcessGDBRemote::GetLoadedDynamicLibrariesInfos (lldb::addr_t image_list_address, lldb::addr_t image_count)
+{
+    StructuredData::ObjectSP object_sp;
+
+    if (m_gdb_comm.GetLoadedDynamicLibrariesInfosSupported())
+    {
+        StructuredData::ObjectSP args_dict(new StructuredData::Dictionary());
+        args_dict->GetAsDictionary()->AddIntegerItem ("image_list_address", image_list_address);
+        args_dict->GetAsDictionary()->AddIntegerItem ("image_count", image_count);
+
+        StreamString packet;
+        packet << "jGetLoadedDynamicLibrariesInfos:";
+        args_dict->Dump (packet);
+
+        // FIXME the final character of a JSON dictionary, '}', is the escape
+        // character in gdb-remote binary mode.  lldb currently doesn't escape
+        // these characters in its packet output -- so we add the quoted version
+        // of the } character here manually in case we talk to a debugserver which
+        // un-escapes the characters at packet read time.
+        packet << (char) (0x7d ^ 0x20);
+
+        StringExtractorGDBRemote response;
+        if (m_gdb_comm.SendPacketAndWaitForResponse(packet.GetData(), packet.GetSize(), response, false) == GDBRemoteCommunication::PacketResult::Success)
+        {
+            StringExtractorGDBRemote::ResponseType response_type = response.GetResponseType();
+            if (response_type == StringExtractorGDBRemote::eResponse)
+            {
+                if (!response.Empty())
+                {
                     // The packet has already had the 0x7d xor quoting stripped out at the
                     // GDBRemoteCommunication packet receive level.
                     object_sp = StructuredData::ParseJSON (response.GetStringRef());
@@ -3995,6 +3998,7 @@ ProcessGDBRemote::GetExtendedInfoForThread (lldb::tid_t tid)
     return object_sp;
 }
 
+
 // Establish the largest memory read/write payloads we should use.
 // If the remote stub has a max packet size, stay under that size.
 // 
@@ -4418,83 +4422,135 @@ ProcessGDBRemote::GetLoadedModuleList (GDBLoadedModuleInfoList & list)
     GDBRemoteCommunicationClient & comm = m_gdb_comm;
 
     // check that we have extended feature read support
-    if (!comm.GetQXferLibrariesSVR4ReadSupported ())
-        return Error (0, ErrorType::eErrorTypeGeneric);
+    if (comm.GetQXferLibrariesSVR4ReadSupported ()) {
+        list.clear ();
 
-    list.clear ();
+        // request the loaded library list
+        std::string raw;
+        lldb_private::Error lldberr;
 
-    // request the loaded library list
-    std::string raw;
-    lldb_private::Error lldberr;
-    if (!comm.ReadExtFeature (ConstString ("libraries-svr4"), ConstString (""), raw, lldberr))
-        return Error (0, ErrorType::eErrorTypeGeneric);
+        if (!comm.ReadExtFeature (ConstString ("libraries-svr4"), ConstString (""), raw, lldberr))
+          return Error (0, ErrorType::eErrorTypeGeneric);
 
-    // parse the xml file in memory
-    if (log)
-        log->Printf ("parsing: %s", raw.c_str());
-    XMLDocument doc;
-    
-    if (!doc.ParseMemory(raw.c_str(), raw.size(), "noname.xml"))
-        return Error (0, ErrorType::eErrorTypeGeneric);
+        // parse the xml file in memory
+        if (log)
+            log->Printf ("parsing: %s", raw.c_str());
+        XMLDocument doc;
+        
+        if (!doc.ParseMemory(raw.c_str(), raw.size(), "noname.xml"))
+            return Error (0, ErrorType::eErrorTypeGeneric);
 
-    XMLNode root_element = doc.GetRootElement("library-list-svr4");
-    if (!root_element)
-        return Error();
+        XMLNode root_element = doc.GetRootElement("library-list-svr4");
+        if (!root_element)
+            return Error();
 
-    // main link map structure
-    llvm::StringRef main_lm = root_element.GetAttributeValue("main-lm");
-    if (!main_lm.empty())
-    {
-        list.m_link_map = StringConvert::ToUInt64(main_lm.data(), LLDB_INVALID_ADDRESS, 0);
-    }
+        // main link map structure
+        llvm::StringRef main_lm = root_element.GetAttributeValue("main-lm");
+        if (!main_lm.empty())
+        {
+            list.m_link_map = StringConvert::ToUInt64(main_lm.data(), LLDB_INVALID_ADDRESS, 0);
+        }
 
-    root_element.ForEachChildElementWithName("library", [log, &list](const XMLNode &library) -> bool {
+        root_element.ForEachChildElementWithName("library", [log, &list](const XMLNode &library) -> bool {
 
-        GDBLoadedModuleInfoList::LoadedModuleInfo module;
+            GDBLoadedModuleInfoList::LoadedModuleInfo module;
 
-        library.ForEachAttribute([log, &module](const llvm::StringRef &name, const llvm::StringRef &value) -> bool {
-            
-            if (name == "name")
-                module.set_name (value.str());
-            else if (name == "lm")
-            {
-                // the address of the link_map struct.
-                module.set_link_map(StringConvert::ToUInt64(value.data(), LLDB_INVALID_ADDRESS, 0));
-            }
-            else if (name == "l_addr")
-            {
-                // the displacement as read from the field 'l_addr' of the link_map struct.
-                module.set_base(StringConvert::ToUInt64(value.data(), LLDB_INVALID_ADDRESS, 0));
+            library.ForEachAttribute([log, &module](const llvm::StringRef &name, const llvm::StringRef &value) -> bool {
                 
-            }
-            else if (name == "l_ld")
+                if (name == "name")
+                    module.set_name (value.str());
+                else if (name == "lm")
+                {
+                    // the address of the link_map struct.
+                    module.set_link_map(StringConvert::ToUInt64(value.data(), LLDB_INVALID_ADDRESS, 0));
+                }
+                else if (name == "l_addr")
+                {
+                    // the displacement as read from the field 'l_addr' of the link_map struct.
+                    module.set_base(StringConvert::ToUInt64(value.data(), LLDB_INVALID_ADDRESS, 0));
+                    
+                }
+                else if (name == "l_ld")
+                {
+                    // the memory address of the libraries PT_DYAMIC section.
+                    module.set_dynamic(StringConvert::ToUInt64(value.data(), LLDB_INVALID_ADDRESS, 0));
+                }
+                
+                return true; // Keep iterating over all properties of "library"
+            });
+
+            if (log)
             {
-                // the memory address of the libraries PT_DYAMIC section.
-                module.set_dynamic(StringConvert::ToUInt64(value.data(), LLDB_INVALID_ADDRESS, 0));
+                std::string name;
+                lldb::addr_t lm=0, base=0, ld=0;
+
+                module.get_name (name);
+                module.get_link_map (lm);
+                module.get_base (base);
+                module.get_dynamic (ld);
+
+                log->Printf ("found (link_map:0x08%" PRIx64 ", base:0x08%" PRIx64 ", ld:0x08%" PRIx64 ", name:'%s')", lm, base, ld, name.c_str());
             }
-            
-            return true; // Keep iterating over all properties of "library"
+
+            list.add (module);
+            return true; // Keep iterating over all "library" elements in the root node
         });
 
         if (log)
-        {
-            std::string name;
-            lldb::addr_t lm=0, base=0, ld=0;
+            log->Printf ("found %" PRId32 " modules in total", (int) list.m_list.size());
+    } else if (comm.GetQXferLibrariesReadSupported ()) {
+        list.clear ();
 
-            module.get_name (name);
-            module.get_link_map (lm);
-            module.get_base (base);
-            module.get_dynamic (ld);
+        // request the loaded library list
+        std::string raw;
+        lldb_private::Error lldberr;
 
-            log->Printf ("found (link_map:0x08%" PRIx64 ", base:0x08%" PRIx64 ", ld:0x08%" PRIx64 ", name:'%s')", lm, base, ld, name.c_str());
-        }
+        if (!comm.ReadExtFeature (ConstString ("libraries"), ConstString (""), raw, lldberr))
+          return Error (0, ErrorType::eErrorTypeGeneric);
 
-        list.add (module);
-        return true; // Keep iterating over all "library" elements in the root node
-    });
+        if (log)
+            log->Printf ("parsing: %s", raw.c_str());
+        XMLDocument doc;
 
-    if (log)
-        log->Printf ("found %" PRId32 " modules in total", (int) list.m_list.size());
+        if (!doc.ParseMemory(raw.c_str(), raw.size(), "noname.xml"))
+            return Error (0, ErrorType::eErrorTypeGeneric);
+
+        XMLNode root_element = doc.GetRootElement("library-list");
+        if (!root_element)
+            return Error();
+
+        root_element.ForEachChildElementWithName("library", [log, &list](const XMLNode &library) -> bool {
+            GDBLoadedModuleInfoList::LoadedModuleInfo module;
+
+            llvm::StringRef name = library.GetAttributeValue("name");
+            module.set_name(name.str());
+
+            // The base address of a given library will be the address of its
+            // first section. Most remotes send only one section for Windows
+            // targets for example.
+            const XMLNode &section = library.FindFirstChildElementWithName("section");
+            llvm::StringRef address = section.GetAttributeValue("address");
+            module.set_base(StringConvert::ToUInt64(address.data(), LLDB_INVALID_ADDRESS, 0));
+
+            if (log)
+            {
+                std::string name;
+                lldb::addr_t base = 0;
+                module.get_name (name);
+                module.get_base (base);
+
+                log->Printf ("found (base:0x%" PRIx64 ", name:'%s')", base, name.c_str());
+            }
+
+            list.add (module);
+            return true; // Keep iterating over all "library" elements in the root node
+        });
+
+        if (log)
+            log->Printf ("found %" PRId32 " modules in total", (int) list.m_list.size());
+    } else {
+        return Error (0, ErrorType::eErrorTypeGeneric);
+    }
 
     return Error();
 }
diff --git a/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h b/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
index 0a5e4a8a41b4..45c74ea64ee5 100644
--- a/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
+++ b/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
@@ -27,11 +27,11 @@
 #include "lldb/Core/ThreadSafeValue.h"
 #include "lldb/Host/HostThread.h"
 #include "lldb/lldb-private-forward.h"
+#include "lldb/Utility/StringExtractor.h"
 #include "lldb/Target/Process.h"
 #include "lldb/Target/Thread.h"
 
 #include "GDBRemoteCommunicationClient.h"
-#include "Utility/StringExtractor.h"
 #include "GDBRemoteRegisterContext.h"
 
 namespace lldb_private {
@@ -247,6 +247,9 @@ public:
     void
     ModulesDidLoad (ModuleList &module_list) override;
 
+    StructuredData::ObjectSP
+    GetLoadedDynamicLibrariesInfos (lldb::addr_t image_list_address, lldb::addr_t image_count) override;
+
 protected:
     friend class ThreadGDBRemote;
     friend class GDBRemoteCommunicationClient;
diff --git a/source/Plugins/Process/gdb-remote/ThreadGDBRemote.cpp b/source/Plugins/Process/gdb-remote/ThreadGDBRemote.cpp
index 59c701d75a68..d2a6503caf8e 100644
--- a/source/Plugins/Process/gdb-remote/ThreadGDBRemote.cpp
+++ b/source/Plugins/Process/gdb-remote/ThreadGDBRemote.cpp
@@ -215,14 +215,14 @@ ThreadGDBRemote::WillResume (StateType resume_state)
             break;
 
         case eStateRunning:
-            if (gdb_process->GetUnixSignals().SignalIsValid (signo))
+            if (gdb_process->GetUnixSignals()->SignalIsValid(signo))
                 gdb_process->m_continue_C_tids.push_back(std::make_pair(tid, signo));
             else
                 gdb_process->m_continue_c_tids.push_back(tid);
             break;
 
         case eStateStepping:
-            if (gdb_process->GetUnixSignals().SignalIsValid (signo))
+            if (gdb_process->GetUnixSignals()->SignalIsValid(signo))
                 gdb_process->m_continue_S_tids.push_back(std::make_pair(tid, signo));
             else
                 gdb_process->m_continue_s_tids.push_back(tid);
diff --git a/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp b/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp
index 75934f966bcd..60933108c97a 100644
--- a/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp
+++ b/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp
@@ -669,6 +669,7 @@ DWARFCompileUnit::Index (const uint32_t cu_idx,
                                                                 GetOffset());
     }
 
+    const LanguageType cu_language = GetLanguageType();
     DWARFDebugInfoEntry::const_iterator pos;
     DWARFDebugInfoEntry::const_iterator begin = m_die_array.begin();
     DWARFDebugInfoEntry::const_iterator end = m_die_array.end();
@@ -882,8 +883,9 @@ DWARFCompileUnit::Index (const uint32_t cu_idx,
                     {
                         Mangled mangled (ConstString(mangled_cstr), true);
                         func_fullnames.Insert (mangled.GetMangledName(), die.GetOffset());
-                        if (mangled.GetDemangledName())
-                            func_fullnames.Insert (mangled.GetDemangledName(), die.GetOffset());
+                        ConstString demangled = mangled.GetDemangledName(cu_language);
+                        if (demangled)
+                            func_fullnames.Insert (demangled, die.GetOffset());
                     }
                 }
             }
@@ -904,8 +906,9 @@ DWARFCompileUnit::Index (const uint32_t cu_idx,
                     {
                         Mangled mangled (ConstString(mangled_cstr), true);
                         func_fullnames.Insert (mangled.GetMangledName(), die.GetOffset());
-                        if (mangled.GetDemangledName())
-                            func_fullnames.Insert (mangled.GetDemangledName(), die.GetOffset());
+                        ConstString demangled = mangled.GetDemangledName(cu_language);
+                        if (demangled)
+                            func_fullnames.Insert (demangled, die.GetOffset());
                     }
                 }
                 else
@@ -951,8 +954,9 @@ DWARFCompileUnit::Index (const uint32_t cu_idx,
                 {
                     Mangled mangled (ConstString(mangled_cstr), true);
                     globals.Insert (mangled.GetMangledName(), die.GetOffset());
-                    if (mangled.GetDemangledName())
-                        globals.Insert (mangled.GetDemangledName(), die.GetOffset());
+                    ConstString demangled = mangled.GetDemangledName(cu_language);
+                    if (demangled)
+                        globals.Insert (demangled, die.GetOffset());
                 }
             }
             break;
diff --git a/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp b/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
index dafd389449a2..ea8aedcc2be0 100644
--- a/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
+++ b/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
@@ -988,24 +988,38 @@ SymbolFileDWARF::ParseCompileUnit (DWARFCompileUnit* dwarf_cu, uint32_t cu_idx)
                             std::string remapped_file;
                             if (module_sp->RemapSourceFile(cu_file_spec.GetCString(), remapped_file))
                                 cu_file_spec.SetFile(remapped_file, false);
+                        }
 
-                            LanguageType cu_language = DWARFCompileUnit::LanguageTypeFromDWARF(cu_die->GetAttributeValueAsUnsigned(this, dwarf_cu, DW_AT_language, 0));
+                        LanguageType cu_language = DWARFCompileUnit::LanguageTypeFromDWARF(cu_die->GetAttributeValueAsUnsigned(this, dwarf_cu, DW_AT_language, 0));
 
-                            cu_sp.reset(new CompileUnit (module_sp,
-                                                         dwarf_cu,
-                                                         cu_file_spec, 
-                                                         MakeUserID(dwarf_cu->GetOffset()),
-                                                         cu_language));
-                            if (cu_sp)
+                        cu_sp.reset(new CompileUnit (module_sp,
+                                                     dwarf_cu,
+                                                     cu_file_spec, 
+                                                     MakeUserID(dwarf_cu->GetOffset()),
+                                                     cu_language));
+                        if (cu_sp)
+                        {
+                            // If we just created a compile unit with an invalid file spec, try and get the
+                            // first entry in the supports files from the line table as that should be the
+                            // compile unit.
+                            if (!cu_file_spec)
                             {
-                                dwarf_cu->SetUserData(cu_sp.get());
-                                
-                                // Figure out the compile unit index if we weren't given one
-                                if (cu_idx == UINT32_MAX)
-                                    DebugInfo()->GetCompileUnit(dwarf_cu->GetOffset(), &cu_idx);
-                                
-                                m_obj_file->GetModule()->GetSymbolVendor()->SetCompileUnitAtIndex(cu_idx, cu_sp);
+                                cu_file_spec = cu_sp->GetSupportFiles().GetFileSpecAtIndex(1);
+                                if (cu_file_spec)
+                                {
+                                    (FileSpec &)(*cu_sp) = cu_file_spec;
+                                    // Also fix the invalid file spec which was copied from the compile unit.
+                                    cu_sp->GetSupportFiles().Replace(0, cu_file_spec);
+                                }
                             }
+
+                            dwarf_cu->SetUserData(cu_sp.get());
+                            
+                            // Figure out the compile unit index if we weren't given one
+                            if (cu_idx == UINT32_MAX)
+                                DebugInfo()->GetCompileUnit(dwarf_cu->GetOffset(), &cu_idx);
+                            
+                            m_obj_file->GetModule()->GetSymbolVendor()->SetCompileUnitAtIndex(cu_idx, cu_sp);
                         }
                     }
                 }
@@ -2196,7 +2210,7 @@ SymbolFileDWARF::ParseChildMembers
                             }
                         }
                         
-                        if (prop_name != NULL)
+                        if (prop_name != NULL && member_type)
                         {
                             clang::ObjCIvarDecl *ivar_decl = NULL;
                             
@@ -3761,9 +3775,10 @@ SymbolFileDWARF::FunctionDieMatchesPartialName (const DWARFDebugInfoEntry* die,
             }
         }
 
-        if (best_name.GetDemangledName())
+        const LanguageType cu_language = const_cast<DWARFCompileUnit *>(dwarf_cu)->GetLanguageType();
+        if (best_name.GetDemangledName(cu_language))
         {
-            const char *demangled = best_name.GetDemangledName().GetCString();
+            const char *demangled = best_name.GetDemangledName(cu_language).GetCString();
             if (demangled)
             {
                 std::string name_no_parens(partial_name, base_name_end - partial_name);
diff --git a/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp b/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
index 5579a23ce716..de972acd7ed7 100644
--- a/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
+++ b/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
@@ -113,7 +113,7 @@ SymbolFileDWARFDebugMap::CompileUnitInfo::GetFileRangeMap(SymbolFileDWARFDebugMa
                             // correctly to the new addresses in the main executable.
 
                             // First we find the original symbol in the .o file's symbol table
-                            Symbol *oso_fun_symbol = oso_symtab->FindFirstSymbolWithNameAndType (exe_symbol->GetMangled().GetName(Mangled::ePreferMangled),
+                            Symbol *oso_fun_symbol = oso_symtab->FindFirstSymbolWithNameAndType (exe_symbol->GetMangled().GetName(lldb::eLanguageTypeUnknown, Mangled::ePreferMangled),
                                                                                                  eSymbolTypeCode,
                                                                                                  Symtab::eDebugNo,
                                                                                                  Symtab::eVisibilityAny);
@@ -145,7 +145,7 @@ SymbolFileDWARFDebugMap::CompileUnitInfo::GetFileRangeMap(SymbolFileDWARFDebugMa
                             // sizes from the DWARF info as we are parsing.
 
                             // Next we find the non-stab entry that corresponds to the N_GSYM in the .o file
-                            Symbol *oso_gsym_symbol = oso_symtab->FindFirstSymbolWithNameAndType (exe_symbol->GetMangled().GetName(Mangled::ePreferMangled),
+                            Symbol *oso_gsym_symbol = oso_symtab->FindFirstSymbolWithNameAndType (exe_symbol->GetMangled().GetName(lldb::eLanguageTypeUnknown, Mangled::ePreferMangled),
                                                                                                   eSymbolTypeData,
                                                                                                   Symtab::eDebugNo,
                                                                                                   Symtab::eVisibilityAny);
diff --git a/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.cpp b/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.cpp
index 64c88ab716bf..09b919782608 100644
--- a/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.cpp
+++ b/source/Plugins/SymbolFile/Symtab/SymbolFileSymtab.cpp
@@ -161,7 +161,7 @@ SymbolFileSymtab::ParseCompileUnitAtIndex(uint32_t idx)
     {
         const Symbol *cu_symbol = m_obj_file->GetSymtab()->SymbolAtIndex(m_source_indexes[idx]);
         if (cu_symbol)
-            cu_sp.reset(new CompileUnit (m_obj_file->GetModule(), NULL, cu_symbol->GetMangled().GetName().AsCString(), 0, eLanguageTypeUnknown));
+            cu_sp.reset(new CompileUnit (m_obj_file->GetModule(), NULL, cu_symbol->GetName().AsCString(), 0, eLanguageTypeUnknown));
     }
     return cu_sp;
 }