<rdar://problem/15172417>
Added two new GDB server packets to debugserver: "QSaveRegisterState" and "QRestoreRegiterState".
"QSaveRegisterState" makes the remote GDB server save all register values and it returns a save identifier as an unsigned integer. This packet can be used prior to running expressions to save all registers.
All registers can them we later restored with "QRestoreRegiterState:SAVEID" what SAVEID is the integer identifier that was returned from the call to QSaveRegisterState.
Cleaned up redundant code in lldb_private::Thread, lldb_private::ThreadPlanCallFunction.
Moved the lldb_private::Thread::RegisterCheckpoint into its own header file and it is now in the lldb_private namespace. Trimmed down the RegisterCheckpoint class to omit stuff that wasn't used (the stack ID).
Added a few new virtual methods to lldb_private::RegisterContext that allow subclasses to efficiently save/restore register states and changed the RegisterContextGDBRemote to take advantage of these new calls.
llvm-svn: 194621
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
index 2ac7d20..da2299a 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp
@@ -65,6 +65,7 @@
m_attach_or_wait_reply(eLazyBoolCalculate),
m_prepare_for_reg_writing_reply (eLazyBoolCalculate),
m_supports_p (eLazyBoolCalculate),
+ m_supports_QSaveRegisterState (eLazyBoolCalculate),
m_supports_qProcessInfoPID (true),
m_supports_qfProcessInfo (true),
m_supports_qUserName (true),
@@ -208,6 +209,7 @@
m_supports_vCont_s = eLazyBoolCalculate;
m_supports_vCont_S = eLazyBoolCalculate;
m_supports_p = eLazyBoolCalculate;
+ m_supports_QSaveRegisterState = eLazyBoolCalculate;
m_qHostInfo_is_valid = eLazyBoolCalculate;
m_qProcessInfo_is_valid = eLazyBoolCalculate;
m_supports_alloc_dealloc_memory = eLazyBoolCalculate;
@@ -2809,3 +2811,134 @@
}
return false;
}
+
+bool
+GDBRemoteCommunicationClient::ReadRegister(lldb::tid_t tid, uint32_t reg, StringExtractorGDBRemote &response)
+{
+ Mutex::Locker locker;
+ if (GetSequenceMutex (locker, "Didn't get sequence mutex for p packet."))
+ {
+ const bool thread_suffix_supported = GetThreadSuffixSupported();
+
+ if (thread_suffix_supported || SetCurrentThread(tid))
+ {
+ char packet[64];
+ int packet_len = 0;
+ if (thread_suffix_supported)
+ packet_len = ::snprintf (packet, sizeof(packet), "p%x;thread:%4.4" PRIx64 ";", reg, tid);
+ else
+ packet_len = ::snprintf (packet, sizeof(packet), "p%x", reg);
+ assert (packet_len < ((int)sizeof(packet) - 1));
+ return SendPacketAndWaitForResponse(packet, response, false);
+ }
+ }
+ return false;
+
+}
+
+
+bool
+GDBRemoteCommunicationClient::ReadAllRegisters (lldb::tid_t tid, StringExtractorGDBRemote &response)
+{
+ Mutex::Locker locker;
+ if (GetSequenceMutex (locker, "Didn't get sequence mutex for g packet."))
+ {
+ const bool thread_suffix_supported = GetThreadSuffixSupported();
+
+ if (thread_suffix_supported || SetCurrentThread(tid))
+ {
+ char packet[64];
+ int packet_len = 0;
+ // Get all registers in one packet
+ if (thread_suffix_supported)
+ packet_len = ::snprintf (packet, sizeof(packet), "g;thread:%4.4" PRIx64 ";", tid);
+ else
+ packet_len = ::snprintf (packet, sizeof(packet), "g");
+ assert (packet_len < ((int)sizeof(packet) - 1));
+ return SendPacketAndWaitForResponse(packet, response, false);
+ }
+ }
+ return false;
+}
+bool
+GDBRemoteCommunicationClient::SaveRegisterState (lldb::tid_t tid, uint32_t &save_id)
+{
+ save_id = 0; // Set to invalid save ID
+ if (m_supports_QSaveRegisterState == eLazyBoolNo)
+ return false;
+
+ m_supports_QSaveRegisterState = eLazyBoolYes;
+ Mutex::Locker locker;
+ if (GetSequenceMutex (locker, "Didn't get sequence mutex for QSaveRegisterState."))
+ {
+ const bool thread_suffix_supported = GetThreadSuffixSupported();
+ if (thread_suffix_supported || SetCurrentThread(tid))
+ {
+ char packet[256];
+ if (thread_suffix_supported)
+ ::snprintf (packet, sizeof(packet), "QSaveRegisterState;thread:%4.4" PRIx64 ";", tid);
+ else
+ ::strncpy (packet, "QSaveRegisterState", sizeof(packet));
+
+ StringExtractorGDBRemote response;
+
+ if (SendPacketAndWaitForResponse(packet, response, false))
+ {
+ if (response.IsUnsupportedResponse())
+ {
+ // This packet isn't supported, don't try calling it again
+ m_supports_QSaveRegisterState = eLazyBoolNo;
+ }
+
+ const uint32_t response_save_id = response.GetU32(0);
+ if (response_save_id != 0)
+ {
+ save_id = response_save_id;
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+}
+
+bool
+GDBRemoteCommunicationClient::RestoreRegisterState (lldb::tid_t tid, uint32_t save_id)
+{
+ // We use the "m_supports_QSaveRegisterState" variable here becuase the
+ // QSaveRegisterState and QRestoreRegisterState packets must both be supported in
+ // order to be useful
+ if (m_supports_QSaveRegisterState == eLazyBoolNo)
+ return false;
+
+ Mutex::Locker locker;
+ if (GetSequenceMutex (locker, "Didn't get sequence mutex for QRestoreRegisterState."))
+ {
+ const bool thread_suffix_supported = GetThreadSuffixSupported();
+ if (thread_suffix_supported || SetCurrentThread(tid))
+ {
+ char packet[256];
+ if (thread_suffix_supported)
+ ::snprintf (packet, sizeof(packet), "QRestoreRegisterState:%u;thread:%4.4" PRIx64 ";", save_id, tid);
+ else
+ ::snprintf (packet, sizeof(packet), "QRestoreRegisterState:%u" PRIx64 ";", save_id);
+
+ StringExtractorGDBRemote response;
+
+ if (SendPacketAndWaitForResponse(packet, response, false))
+ {
+ if (response.IsOKResponse())
+ {
+ return true;
+ }
+ else if (response.IsUnsupportedResponse())
+ {
+ // This packet isn't supported, don't try calling this packet or
+ // QSaveRegisterState again...
+ m_supports_QSaveRegisterState = eLazyBoolNo;
+ }
+ }
+ }
+ }
+ return false;
+}
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
index d5535bb..530655b 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
@@ -411,6 +411,21 @@
HarmonizeThreadIdsForProfileData (ProcessGDBRemote *process,
StringExtractorGDBRemote &inputStringExtractor);
+ bool
+ ReadRegister(lldb::tid_t tid,
+ uint32_t reg_num,
+ StringExtractorGDBRemote &response);
+
+ bool
+ ReadAllRegisters (lldb::tid_t tid,
+ StringExtractorGDBRemote &response);
+
+ bool
+ SaveRegisterState (lldb::tid_t tid, uint32_t &save_id);
+
+ bool
+ RestoreRegisterState (lldb::tid_t tid, uint32_t save_id);
+
protected:
bool
@@ -438,6 +453,7 @@
lldb_private::LazyBool m_attach_or_wait_reply;
lldb_private::LazyBool m_prepare_for_reg_writing_reply;
lldb_private::LazyBool m_supports_p;
+ lldb_private::LazyBool m_supports_QSaveRegisterState;
bool
m_supports_qProcessInfoPID:1,
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteRegisterContext.cpp b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteRegisterContext.cpp
index c4e468f..c291df7 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteRegisterContext.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteRegisterContext.cpp
@@ -153,20 +153,13 @@
GDBRemoteRegisterContext::GetPrimordialRegister(const lldb_private::RegisterInfo *reg_info,
GDBRemoteCommunicationClient &gdb_comm)
{
- char packet[64];
- StringExtractorGDBRemote response;
- int packet_len = 0;
const uint32_t reg = reg_info->kinds[eRegisterKindLLDB];
- if (gdb_comm.GetThreadSuffixSupported())
- packet_len = ::snprintf (packet, sizeof(packet), "p%x;thread:%4.4" PRIx64 ";", reg, m_thread.GetProtocolID());
- else
- packet_len = ::snprintf (packet, sizeof(packet), "p%x", reg);
- assert (packet_len < ((int)sizeof(packet) - 1));
- if (gdb_comm.SendPacketAndWaitForResponse(packet, response, false))
+ StringExtractorGDBRemote response;
+ if (gdb_comm.ReadRegister(m_thread.GetProtocolID(), reg, response))
return PrivateSetRegisterValue (reg, response);
-
return false;
}
+
bool
GDBRemoteRegisterContext::ReadRegisterBytes (const RegisterInfo *reg_info, DataExtractor &data)
{
@@ -185,93 +178,51 @@
if (!GetRegisterIsValid(reg))
{
- Mutex::Locker locker;
- if (gdb_comm.GetSequenceMutex (locker, "Didn't get sequence mutex for read register."))
+ if (m_read_all_at_once)
{
- const bool thread_suffix_supported = gdb_comm.GetThreadSuffixSupported();
- ProcessSP process_sp (m_thread.GetProcess());
- if (thread_suffix_supported || static_cast<ProcessGDBRemote *>(process_sp.get())->GetGDBRemote().SetCurrentThread(m_thread.GetProtocolID()))
+ StringExtractorGDBRemote response;
+ if (!gdb_comm.ReadAllRegisters(m_thread.GetProtocolID(), response))
+ return false;
+ if (response.IsNormalResponse())
+ if (response.GetHexBytes ((void *)m_reg_data.GetDataStart(), m_reg_data.GetByteSize(), '\xcc') == m_reg_data.GetByteSize())
+ SetAllRegisterValid (true);
+ }
+ else if (reg_info->value_regs)
+ {
+ // Process this composite register request by delegating to the constituent
+ // primordial registers.
+
+ // Index of the primordial register.
+ bool success = true;
+ for (uint32_t idx = 0; success; ++idx)
{
- char packet[64];
- StringExtractorGDBRemote response;
- int packet_len = 0;
- if (m_read_all_at_once)
- {
- // Get all registers in one packet
- if (thread_suffix_supported)
- packet_len = ::snprintf (packet, sizeof(packet), "g;thread:%4.4" PRIx64 ";", m_thread.GetProtocolID());
- else
- packet_len = ::snprintf (packet, sizeof(packet), "g");
- assert (packet_len < ((int)sizeof(packet) - 1));
- if (gdb_comm.SendPacketAndWaitForResponse(packet, response, false))
- {
- if (response.IsNormalResponse())
- if (response.GetHexBytes ((void *)m_reg_data.GetDataStart(), m_reg_data.GetByteSize(), '\xcc') == m_reg_data.GetByteSize())
- SetAllRegisterValid (true);
- }
- }
- else if (reg_info->value_regs)
- {
- // Process this composite register request by delegating to the constituent
- // primordial registers.
-
- // Index of the primordial register.
- bool success = true;
- for (uint32_t idx = 0; success; ++idx)
- {
- const uint32_t prim_reg = reg_info->value_regs[idx];
- if (prim_reg == LLDB_INVALID_REGNUM)
- break;
- // We have a valid primordial regsiter as our constituent.
- // Grab the corresponding register info.
- const RegisterInfo *prim_reg_info = GetRegisterInfoAtIndex(prim_reg);
- if (prim_reg_info == NULL)
- success = false;
- else
- {
- // Read the containing register if it hasn't already been read
- if (!GetRegisterIsValid(prim_reg))
- success = GetPrimordialRegister(prim_reg_info, gdb_comm);
- }
- }
-
- if (success)
- {
- // If we reach this point, all primordial register requests have succeeded.
- // Validate this composite register.
- SetRegisterIsValid (reg_info, true);
- }
- }
+ const uint32_t prim_reg = reg_info->value_regs[idx];
+ if (prim_reg == LLDB_INVALID_REGNUM)
+ break;
+ // We have a valid primordial regsiter as our constituent.
+ // Grab the corresponding register info.
+ const RegisterInfo *prim_reg_info = GetRegisterInfoAtIndex(prim_reg);
+ if (prim_reg_info == NULL)
+ success = false;
else
{
- // Get each register individually
- GetPrimordialRegister(reg_info, gdb_comm);
+ // Read the containing register if it hasn't already been read
+ if (!GetRegisterIsValid(prim_reg))
+ success = GetPrimordialRegister(prim_reg_info, gdb_comm);
}
}
+
+ if (success)
+ {
+ // If we reach this point, all primordial register requests have succeeded.
+ // Validate this composite register.
+ SetRegisterIsValid (reg_info, true);
+ }
}
else
{
-#if LLDB_CONFIGURATION_DEBUG
- StreamString strm;
- gdb_comm.DumpHistory(strm);
- Host::SetCrashDescription (strm.GetData());
- assert (!"Didn't get sequence mutex for read register.");
-#else
- Log *log (ProcessGDBRemoteLog::GetLogIfAnyCategoryIsSet (GDBR_LOG_THREAD | GDBR_LOG_PACKETS));
- if (log)
- {
- if (log->GetVerbose())
- {
- StreamString strm;
- gdb_comm.DumpHistory(strm);
- log->Printf("error: failed to get packet sequence mutex, not sending read register for \"%s\":\n%s", reg_info->name, strm.GetData());
- }
- else
- {
- log->Printf("error: failed to get packet sequence mutex, not sending read register for \"%s\"", reg_info->name);
- }
- }
-#endif
+ // Get each register individually
+ GetPrimordialRegister(reg_info, gdb_comm);
}
// Make sure we got a valid register value after reading it
@@ -488,6 +439,54 @@
return false;
}
+bool
+GDBRemoteRegisterContext::ReadAllRegisterValues (lldb_private::RegisterCheckpoint ®_checkpoint)
+{
+ ExecutionContext exe_ctx (CalculateThread());
+
+ Process *process = exe_ctx.GetProcessPtr();
+ Thread *thread = exe_ctx.GetThreadPtr();
+ if (process == NULL || thread == NULL)
+ return false;
+
+ GDBRemoteCommunicationClient &gdb_comm (((ProcessGDBRemote *)process)->GetGDBRemote());
+
+ uint32_t save_id = 0;
+ if (gdb_comm.SaveRegisterState(thread->GetProtocolID(), save_id))
+ {
+ reg_checkpoint.SetID(save_id);
+ reg_checkpoint.GetData().reset();
+ return true;
+ }
+ else
+ {
+ reg_checkpoint.SetID(0); // Invalid save ID is zero
+ return ReadAllRegisterValues(reg_checkpoint.GetData());
+ }
+}
+
+bool
+GDBRemoteRegisterContext::WriteAllRegisterValues (const lldb_private::RegisterCheckpoint ®_checkpoint)
+{
+ uint32_t save_id = reg_checkpoint.GetID();
+ if (save_id != 0)
+ {
+ ExecutionContext exe_ctx (CalculateThread());
+
+ Process *process = exe_ctx.GetProcessPtr();
+ Thread *thread = exe_ctx.GetThreadPtr();
+ if (process == NULL || thread == NULL)
+ return false;
+
+ GDBRemoteCommunicationClient &gdb_comm (((ProcessGDBRemote *)process)->GetGDBRemote());
+
+ return gdb_comm.RestoreRegisterState(m_thread.GetProtocolID(), save_id);
+ }
+ else
+ {
+ return WriteAllRegisterValues(reg_checkpoint.GetData());
+ }
+}
bool
GDBRemoteRegisterContext::ReadAllRegisterValues (lldb::DataBufferSP &data_sp)
diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteRegisterContext.h b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteRegisterContext.h
index 7a49d69..38f29bb 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteRegisterContext.h
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteRegisterContext.h
@@ -91,6 +91,12 @@
virtual bool
WriteAllRegisterValues (const lldb::DataBufferSP &data_sp);
+ virtual bool
+ ReadAllRegisterValues (lldb_private::RegisterCheckpoint ®_checkpoint);
+
+ virtual bool
+ WriteAllRegisterValues (const lldb_private::RegisterCheckpoint ®_checkpoint);
+
virtual uint32_t
ConvertRegisterKindToRegisterNumber (uint32_t kind, uint32_t num);