Battery of NetBSD support improvements

Summary:
Include initial support for:
 - single step mode (PT_STEP)
 - single step trap handling (TRAP_TRACE)
 - exec() trap (TRAP_EXEC)
 - add placeholder interfaces for FPR
 - initial code for NetBSD core(5) files
 - minor tweaks

While there improve style of altered elf-core/ files.

This code raises the number of passing tests on NetBSD to around 50% (600+/1200+).

The introduced code is subject to improve afterwards for additional features and bug fixes.

Sponsored by <The NetBSD Foundation>

Reviewers: labath, joerg, emaste, kettenis

Reviewed By: labath

Subscribers: srhines, #lldb

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D31450

llvm-svn: 299109
diff --git a/lldb/source/Plugins/Process/NetBSD/NativeThreadNetBSD.cpp b/lldb/source/Plugins/Process/NetBSD/NativeThreadNetBSD.cpp
index 8493e98..f23621e 100644
--- a/lldb/source/Plugins/Process/NetBSD/NativeThreadNetBSD.cpp
+++ b/lldb/source/Plugins/Process/NetBSD/NativeThreadNetBSD.cpp
@@ -56,6 +56,18 @@
   m_stop_info.details.signal.signo = SIGTRAP;
 }
 
+void NativeThreadNetBSD::SetStoppedByTrace() {
+  SetStopped();
+  m_stop_info.reason = StopReason::eStopReasonTrace;
+  m_stop_info.details.signal.signo = SIGTRAP;
+}
+
+void NativeThreadNetBSD::SetStoppedByExec() {
+  SetStopped();
+  m_stop_info.reason = StopReason::eStopReasonExec;
+  m_stop_info.details.signal.signo = SIGTRAP;
+}
+
 void NativeThreadNetBSD::SetStopped() {
   const StateType new_state = StateType::eStateStopped;
   m_state = new_state;
@@ -67,6 +79,11 @@
   m_stop_info.reason = StopReason::eStopReasonNone;
 }
 
+void NativeThreadNetBSD::SetStepping() {
+  m_state = StateType::eStateStepping;
+  m_stop_info.reason = StopReason::eStopReasonNone;
+}
+
 std::string NativeThreadNetBSD::GetName() { return std::string(""); }
 
 lldb::StateType NativeThreadNetBSD::GetState() { return m_state; }