Use the minidump exception record if present

If the minidump contains a saved exception record use it automatically.

Differential Revision: https://reviews.llvm.org/D56293

llvm-svn: 350546

lldb/lit/Minidump/Windows/Sigsegv/Inputs/sigsegv.cpp

@@ -0,0 +1,40 @@
+
+// nodefaultlib build: cl -Zi sigsegv.cpp /link /nodefaultlib
+
+#ifdef USE_CRT
+#include <stdio.h>
+#else
+int main();
+extern "C"
+{
+    int _fltused;
+    void mainCRTStartup() { main(); }
+    void printf(const char*, ...) {}
+}
+#endif
+
+void crash(bool crash_self)
+{
+    printf("Before...\n");
+    if(crash_self)
+    {
+        printf("Crashing in 3, 2, 1 ...\n");
+        *(volatile int*)nullptr = 0;
+    }
+    printf("After...\n");
+}
+
+int foo(int x, float y, const char* msg)
+{
+    bool flag = x > y;
+    if(flag)
+        printf("x = %d, y = %f, msg = %s\n", x, y, msg);
+    crash(flag);
+    return x << 1;
+}
+
+int main()
+{
+    foo(10, 3.14, "testing");
+}
+

lldb/lit/Minidump/Windows/Sigsegv/Inputs/sigsegv.lldbinit

@@ -0,0 +1,2 @@
+bt all
+dis

lldb/lit/Minidump/Windows/Sigsegv/sigsegv.test

@@ -0,0 +1,13 @@
+// RUN: cd %p/Inputs
+// RUN: env LLDB_USE_NATIVE_PDB_READER=1 \
+// RUN:   %lldb -c sigsegv.dmp -s sigsegv.lldbinit | FileCheck %s
+
+CHECK: * thread #1, stop reason = Exception 0xc0000005 encountered at address 0x7ff7a13110d9
+CHECK:   * frame #0: 0x00007ff7a13110d9 sigsegv.exe
+
+CHECK: ->  0x7ff7a13110d9: movl   $0x0, 0x0
+CHECK:     0x7ff7a13110e4: leaq   0x1f45(%rip), %rcx
+CHECK:     0x7ff7a13110eb: callq  0x7ff7a1311019
+CHECK:     0x7ff7a13110f0: addq   $0x28, %rsp
+CHECK:     0x7ff7a13110f4: retq
+CHECK:     0x7ff7a13110f5: int3

lldb/source/Plugins/Process/minidump/MinidumpParser.cpp

@@ -107,11 +107,15 @@ llvm::ArrayRef<MinidumpThread> MinidumpParser::GetThreads() {
 }
 
 llvm::ArrayRef<uint8_t>
-MinidumpParser::GetThreadContext(const MinidumpThread &td) {
-  if (td.thread_context.rva + td.thread_context.data_size > GetData().size())
+MinidumpParser::GetThreadContext(const MinidumpLocationDescriptor &location) {
+  if (location.rva + location.data_size > GetData().size())
     return {};
+  return GetData().slice(location.rva, location.data_size);
+}
 
-  return GetData().slice(td.thread_context.rva, td.thread_context.data_size);
+llvm::ArrayRef<uint8_t>
+MinidumpParser::GetThreadContext(const MinidumpThread &td) {
+  return GetThreadContext(td.thread_context);
 }
 
 llvm::ArrayRef<uint8_t>

lldb/source/Plugins/Process/minidump/MinidumpParser.h

@@ -58,6 +58,9 @@ public:
 
   llvm::ArrayRef<MinidumpThread> GetThreads();
 
+  llvm::ArrayRef<uint8_t>
+  GetThreadContext(const MinidumpLocationDescriptor &location);
+
   llvm::ArrayRef<uint8_t> GetThreadContext(const MinidumpThread &td);
 
   llvm::ArrayRef<uint8_t> GetThreadContextWow64(const MinidumpThread &td);

lldb/source/Plugins/Process/minidump/ProcessMinidump.cpp

@@ -34,6 +34,7 @@
 #include "llvm/Support/Threading.h"
 
 #include "Plugins/Process/Utility/StopInfoMachException.h"
+
 // C includes
 // C++ includes
 
@@ -80,7 +81,7 @@ public:
         section_sp, module->base_of_image);
   }
 
-  ObjectFile *GetObjectFile() override { return nullptr; }
+ObjectFile *GetObjectFile() override { return nullptr; }
 
   SectionList *GetSectionList() override {
     return Module::GetUnifiedSectionList();
@@ -305,19 +306,22 @@ void ProcessMinidump::Clear() { Process::m_thread_list.Clear(); }
 
 bool ProcessMinidump::UpdateThreadList(ThreadList &old_thread_list,
                                        ThreadList &new_thread_list) {
-  uint32_t num_threads = 0;
-  if (m_thread_list.size() > 0)
-    num_threads = m_thread_list.size();
+  for (const MinidumpThread& thread : m_thread_list) {
+    MinidumpLocationDescriptor context_location = thread.thread_context;
+
+    // If the minidump contains an exception context, use it
+    if (m_active_exception != nullptr &&
+        m_active_exception->thread_id == thread.thread_id) {
+      context_location = m_active_exception->thread_context;
+    }
 
-  for (lldb::tid_t tid = 0; tid < num_threads; ++tid) {
     llvm::ArrayRef<uint8_t> context;
     if (!m_is_wow64)
-      context = m_minidump_parser.GetThreadContext(m_thread_list[tid]);
+      context = m_minidump_parser.GetThreadContext(context_location);
     else
-      context = m_minidump_parser.GetThreadContextWow64(m_thread_list[tid]);
+      context = m_minidump_parser.GetThreadContextWow64(thread);
 
-    lldb::ThreadSP thread_sp(
-        new ThreadMinidump(*this, m_thread_list[tid], context));
+    lldb::ThreadSP thread_sp(new ThreadMinidump(*this, thread, context));
     new_thread_list.AddThread(thread_sp);
   }
   return new_thread_list.GetSize(false) > 0;
@@ -549,9 +553,9 @@ public:
     APPEND_OPT(m_dump_linux_all);
     m_option_group.Finalize();
   }
-  
+
   ~CommandObjectProcessMinidumpDump() {}
-  
+
   Options *GetOptions() override { return &m_option_group; }
 
   bool DoExecute(Args &command, CommandReturnObject &result) override {
@@ -563,7 +567,7 @@ public:
       return false;
     }
     SetDefaultOptionsIfNoneAreSet();
-    
+
     ProcessMinidump *process = static_cast<ProcessMinidump *>(
         m_interpreter.GetExecutionContext().GetProcessPtr());
     result.SetStatus(eReturnStatusSuccessFinishResult);
@@ -635,7 +639,7 @@ public:
     LoadSubCommand("dump",
         CommandObjectSP(new CommandObjectProcessMinidumpDump(interpreter)));
   }
-  
+
   ~CommandObjectMultiwordProcessMinidump() {}
 };