Revert "[lldb] [gdb-remote] Include PID in vCont packets if multiprocess"

[Michael137]

Summary

This reverts commit ccb9d4d4addc2fb2aa94cf776d43d8be35365272.

https://reviews.llvm.org/D131758

lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h

public:
   bool GetAugmentedLibrariesSVR4ReadSupported();
 
   bool GetQXferFeaturesReadSupported();
 
   bool GetQXferMemoryMapReadSupported();
 
   bool GetQXferSigInfoReadSupported();
 
-  bool GetMultiprocessSupported();
-
   LazyBool SupportsAllocDeallocMemory() // const
   {
     // Uncomment this to have lldb pretend the debug server doesn't respond to
     // alloc/dealloc memory packets.
     // m_supports_alloc_dealloc_memory = lldb_private::eLazyBoolNo;
     return m_supports_alloc_dealloc_memory;
   }
 

lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp

 
 bool GDBRemoteCommunicationClient::GetQXferSigInfoReadSupported() {
   if (m_supports_qXfer_siginfo_read == eLazyBoolCalculate) {
     GetRemoteQSupported();
   }
   return m_supports_qXfer_siginfo_read == eLazyBoolYes;
 }
 
-bool GDBRemoteCommunicationClient::GetMultiprocessSupported() {
-  if (m_supports_memory_tagging == eLazyBoolCalculate)
-    GetRemoteQSupported();
-  return m_supports_multiprocess == eLazyBoolYes;
-}
-
 uint64_t GDBRemoteCommunicationClient::GetRemoteMaxPacketSize() {
   if (m_max_packet_size == 0) {
     GetRemoteQSupported();
   }
   return m_max_packet_size;
 }
 
 bool GDBRemoteCommunicationClient::QueryNoAckModeSupported() {
if (keep_stopped) {
     if (m_supports_detach_stay_stopped == eLazyBoolNo) {
       error.SetErrorString("Stays stopped not supported by this target.");
       return error;
     } else {
       packet.PutChar('1');
     }
   }
 
-  if (GetMultiprocessSupported()) {
+  if (m_supports_multiprocess) {
     // Some servers (e.g. qemu) require specifying the PID even if only a single
     // process is running.
     if (pid == LLDB_INVALID_PROCESS_ID)
       pid = GetCurrentProcessID();
     packet.PutChar(';');
     packet.PutHex64(pid);
   } else if (pid != LLDB_INVALID_PROCESS_ID) {
     error.SetErrorString("Multiprocess extension not supported by the server.");

lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp

listener_sp->StartListeningForEvents(
         &m_async_broadcaster,
         ProcessGDBRemote::eBroadcastBitAsyncThreadDidExit);
 
     const size_t num_threads = GetThreadList().GetSize();
 
     StreamString continue_packet;
     bool continue_packet_error = false;
     if (m_gdb_comm.HasAnyVContSupport()) {
-      std::string pid_prefix;
-      if (m_gdb_comm.GetMultiprocessSupported())
-        pid_prefix = llvm::formatv("p{0:x-}.", GetID());
-
       if (m_continue_c_tids.size() == num_threads ||
           (m_continue_c_tids.empty() && m_continue_C_tids.empty() &&
            m_continue_s_tids.empty() && m_continue_S_tids.empty())) {
-        // All threads are continuing
-        continue_packet.Format("vCont;c:{0}-1", pid_prefix);
+        // All threads are continuing, just send a "c" packet
+        continue_packet.PutCString("c");
       } else {
         continue_packet.PutCString("vCont");
 
         if (!m_continue_c_tids.empty()) {
           if (m_gdb_comm.GetVContSupported('c')) {
             for (tid_collection::const_iterator
                      t_pos = m_continue_c_tids.begin(),
                      t_end = m_continue_c_tids.end();
                  t_pos != t_end; ++t_pos)
-              continue_packet.Format(";c:{0}{1:x-}", pid_prefix, *t_pos);
+              continue_packet.Printf(";c:%4.4" PRIx64, *t_pos);
           } else
             continue_packet_error = true;
         }
 
         if (!continue_packet_error && !m_continue_C_tids.empty()) {
           if (m_gdb_comm.GetVContSupported('C')) {
             for (tid_sig_collection::const_iterator
                      s_pos = m_continue_C_tids.begin(),
                      s_end = m_continue_C_tids.end();
                  s_pos != s_end; ++s_pos)
-              continue_packet.Format(";C{0:x-2}:{1}{2:x-}", s_pos->second,
-                                     pid_prefix, s_pos->first);
+              continue_packet.Printf(";C%2.2x:%4.4" PRIx64, s_pos->second,
+                                     s_pos->first);
           } else
             continue_packet_error = true;
         }
 
         if (!continue_packet_error && !m_continue_s_tids.empty()) {
           if (m_gdb_comm.GetVContSupported('s')) {
             for (tid_collection::const_iterator
                      t_pos = m_continue_s_tids.begin(),
                      t_end = m_continue_s_tids.end();
                  t_pos != t_end; ++t_pos)
-              continue_packet.Format(";s:{0}{1:x-}", pid_prefix, *t_pos);
+              continue_packet.Printf(";s:%4.4" PRIx64, *t_pos);
           } else
             continue_packet_error = true;
         }
 
         if (!continue_packet_error && !m_continue_S_tids.empty()) {
           if (m_gdb_comm.GetVContSupported('S')) {
             for (tid_sig_collection::const_iterator
                      s_pos = m_continue_S_tids.begin(),
                      s_end = m_continue_S_tids.end();
                  s_pos != s_end; ++s_pos)
-              continue_packet.Format(";S{0:x-2}:{1}{2:x-}", s_pos->second,
-                                     pid_prefix, s_pos->first);
+              continue_packet.Printf(";S%2.2x:%4.4" PRIx64, s_pos->second,
+                                     s_pos->first);
           } else
             continue_packet_error = true;
         }
 
         if (continue_packet_error)
           continue_packet.Clear();
       }
     } else