Initial support for native debugging of x86/x64 Windows processes

Summary: Thanks to Hui Huang and the reviewers for all the help with this patch.

Reviewers: labath, Hui, jfb, clayborg, amccarth

Reviewed By: labath

Subscribers: amccarth, compnerd, dexonsmith, mgorny, jfb, teemperor, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D63165

llvm-svn: 368759

1 files changed, 149 insertions, 0 deletions

diff --git a/lldb/source/Plugins/Process/Windows/Common/NativeThreadWindows.cpp b/lldb/source/Plugins/Process/Windows/Common/NativeThreadWindows.cpp
new file mode 100644
index 00000000000..6fd72d675fb
--- /dev/null
+++ b/lldb/source/Plugins/Process/Windows/Common/NativeThreadWindows.cpp
@@ -0,0 +1,149 @@
+//===-- NativeThreadWindows.cpp ---------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "NativeThreadWindows.h"
+#include "NativeProcessWindows.h"
+
+#include "lldb/Host/HostThread.h"
+#include "lldb/Host/Windows/HostThreadWindows.h"
+#include "lldb/Host/windows/windows.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/State.h"
+
+#include "lldb/lldb-forward.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+NativeThreadWindows::NativeThreadWindows(NativeProcessWindows &process,
+                                         const HostThread &thread)
+    : NativeThreadProtocol(process, thread.GetNativeThread().GetThreadId()),
+      m_stop_info(), m_stop_description(), m_host_thread(thread) {
+  m_reg_context_up =
+      (NativeRegisterContextWindows::CreateHostNativeRegisterContextWindows(
+          process.GetArchitecture(), *this));
+}
+
+Status NativeThreadWindows::DoStop() {
+  if (m_state != eStateStopped) {
+    DWORD previous_suspend_count =
+        ::SuspendThread(m_host_thread.GetNativeThread().GetSystemHandle());
+    if (previous_suspend_count == (DWORD)-1)
+      return Status(::GetLastError(), eErrorTypeWin32);
+
+    m_state = eStateStopped;
+  }
+  return Status();
+}
+
+Status NativeThreadWindows::DoResume(lldb::StateType resume_state) {
+  StateType current_state = GetState();
+  if (resume_state == current_state)
+    return Status();
+
+  if (resume_state == eStateStepping) {
+    uint32_t flags_index =
+        GetRegisterContext().ConvertRegisterKindToRegisterNumber(
+            eRegisterKindGeneric, LLDB_REGNUM_GENERIC_FLAGS);
+    uint64_t flags_value =
+        GetRegisterContext().ReadRegisterAsUnsigned(flags_index, 0);
+    flags_value |= 0x100; // Set the trap flag on the CPU
+    GetRegisterContext().WriteRegisterFromUnsigned(flags_index, flags_value);
+  }
+
+  if (resume_state == eStateStepping || resume_state == eStateRunning) {
+    DWORD previous_suspend_count = 0;
+    HANDLE thread_handle = m_host_thread.GetNativeThread().GetSystemHandle();
+    do {
+      // ResumeThread returns -1 on error, or the thread's *previous* suspend
+      // count on success. This means that the return value is 1 when the thread
+      // was restarted. Note that DWORD is an unsigned int, so we need to
+      // explicitly compare with -1.
+      previous_suspend_count = ::ResumeThread(thread_handle);
+
+      if (previous_suspend_count == (DWORD)-1)
+        return Status(::GetLastError(), eErrorTypeWin32);
+
+    } while (previous_suspend_count > 1);
+    m_state = eStateRunning;
+  }
+
+  return Status();
+}
+
+std::string NativeThreadWindows::GetName() {
+  if (!m_name.empty())
+    return m_name;
+
+  // Name is not a property of the Windows thread. Create one with the
+  // process's.
+  NativeProcessProtocol &process = GetProcess();
+  ProcessInstanceInfo process_info;
+  if (Host::GetProcessInfo(process.GetID(), process_info)) {
+    std::string process_name(process_info.GetName());
+    m_name = process_name;
+  }
+  return m_name;
+}
+
+void NativeThreadWindows::SetStopReason(ThreadStopInfo stop_info,
+                                        std::string description) {
+  m_state = eStateStopped;
+  m_stop_info = stop_info;
+  m_stop_description = description;
+}
+
+bool NativeThreadWindows::GetStopReason(ThreadStopInfo &stop_info,
+                                        std::string &description) {
+  Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_THREAD));
+
+  switch (m_state) {
+  case eStateStopped:
+  case eStateCrashed:
+  case eStateExited:
+  case eStateSuspended:
+  case eStateUnloaded:
+    stop_info = m_stop_info;
+    description = m_stop_description;
+    return true;
+
+  case eStateInvalid:
+  case eStateConnected:
+  case eStateAttaching:
+  case eStateLaunching:
+  case eStateRunning:
+  case eStateStepping:
+  case eStateDetached:
+    if (log) {
+      log->Printf("NativeThreadWindows::%s tid %" PRIu64
+                  " in state %s cannot answer stop reason",
+                  __FUNCTION__, GetID(), StateAsCString(m_state));
+    }
+    return false;
+  }
+  llvm_unreachable("unhandled StateType!");
+}
+
+Status NativeThreadWindows::SetWatchpoint(lldb::addr_t addr, size_t size,
+                                          uint32_t watch_flags, bool hardware) {
+  return Status("unimplemented.");
+}
+
+Status NativeThreadWindows::RemoveWatchpoint(lldb::addr_t addr) {
+  return Status("unimplemented");
+}
+
+Status NativeThreadWindows::SetHardwareBreakpoint(lldb::addr_t addr,
+                                                  size_t size) {
+  return Status("unimplemented.");
+}
+
+Status NativeThreadWindows::RemoveHardwareBreakpoint(lldb::addr_t addr) {
+  return Status("unimplemented.");
+}