Adding a new Minidump post-mortem debugging plugin

Summary:
This plugin resembles the already existing Windows-only Minidump plugin.
The WinMinidumpPlugin uses the Windows API for parsing Minidumps
while this plugin is cross-platform because it includes a Minidump
parser (which is already commited)

It is able to produce a backtrace, to read the general puprose regiters,
inspect local variables, show image list, do memory reads, etc.

For now the only arch that this supports is x86 64 bit
This is because I have only written a register context for that arch.
Others will come in next CLs.

I copied the WinMinidump tests and adapted them a little bit for them to
work with the new plugin (and they pass)
I will add more tests, aiming for better code coverage.

There is still functionality to be added, see TODOs in code.

Reviewers: labath, zturner

Subscribers: beanz, mgorny, amccarth, lldb-commits, modocache

Differential Revision: https://reviews.llvm.org/D25196

llvm-svn: 283259

1 files changed, 102 insertions, 0 deletions

diff --git a/lldb/source/Plugins/Process/minidump/ThreadMinidump.cpp b/lldb/source/Plugins/Process/minidump/ThreadMinidump.cpp
new file mode 100644
index 00000000000..22641da9e69
--- /dev/null
+++ b/lldb/source/Plugins/Process/minidump/ThreadMinidump.cpp
@@ -0,0 +1,102 @@
+//===-- ThreadMinidump.cpp --------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// Project includes
+#include "ThreadMinidump.h"
+#include "ProcessMinidump.h"
+
+#include "RegisterContextMinidump_x86_64.h"
+
+// Other libraries and framework includes
+#include "Plugins/Process/Utility/RegisterContextLinux_x86_64.h"
+
+#include "Plugins/Process/elf-core/RegisterContextPOSIXCore_x86_64.h"
+
+#include "lldb/Core/DataExtractor.h"
+#include "lldb/Core/Log.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/StopInfo.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/Unwind.h"
+
+// C Includes
+// C++ Includes
+
+using namespace lldb;
+using namespace lldb_private;
+using namespace minidump;
+
+ThreadMinidump::ThreadMinidump(Process &process, const MinidumpThread &td,
+                               llvm::ArrayRef<uint8_t> gpregset_data)
+    : Thread(process, td.thread_id), m_thread_reg_ctx_sp(),
+      m_gpregset_data(gpregset_data) {}
+
+ThreadMinidump::~ThreadMinidump() {}
+
+void ThreadMinidump::RefreshStateAfterStop() {}
+
+void ThreadMinidump::ClearStackFrames() {}
+
+RegisterContextSP ThreadMinidump::GetRegisterContext() {
+  if (!m_reg_context_sp) {
+    m_reg_context_sp = CreateRegisterContextForFrame(nullptr);
+  }
+  return m_reg_context_sp;
+}
+
+RegisterContextSP
+ThreadMinidump::CreateRegisterContextForFrame(StackFrame *frame) {
+  RegisterContextSP reg_ctx_sp;
+  uint32_t concrete_frame_idx = 0;
+  Log *log(GetLogIfAllCategoriesSet(LIBLLDB_LOG_THREAD));
+
+  if (frame)
+    concrete_frame_idx = frame->GetConcreteFrameIndex();
+
+  if (concrete_frame_idx == 0) {
+    if (m_thread_reg_ctx_sp)
+      return m_thread_reg_ctx_sp;
+
+    ProcessMinidump *process =
+        static_cast<ProcessMinidump *>(GetProcess().get());
+    ArchSpec arch = process->GetArchitecture();
+    RegisterInfoInterface *reg_interface = nullptr;
+
+    // TODO write other register contexts and add them here
+    switch (arch.GetMachine()) {
+    case llvm::Triple::x86_64: {
+      reg_interface = new RegisterContextLinux_x86_64(arch);
+      lldb::DataBufferSP buf =
+          ConvertMinidumpContextToRegIface(m_gpregset_data, reg_interface);
+      DataExtractor gpregs(buf, lldb::eByteOrderLittle, 8);
+      DataExtractor fpregs;
+      m_thread_reg_ctx_sp.reset(new RegisterContextCorePOSIX_x86_64(
+          *this, reg_interface, gpregs, fpregs));
+      break;
+    }
+    default:
+      break;
+    }
+
+    if (!reg_interface) {
+      if (log)
+        log->Printf("elf-core::%s:: Architecture(%d) not supported",
+                    __FUNCTION__, arch.GetMachine());
+      assert(false && "Architecture not supported");
+    }
+
+    reg_ctx_sp = m_thread_reg_ctx_sp;
+  } else if (m_unwinder_ap) {
+    reg_ctx_sp = m_unwinder_ap->CreateRegisterContextForFrame(frame);
+  }
+
+  return reg_ctx_sp;
+}
+
+bool ThreadMinidump::CalculateStopInfo() { return false; }