1 //===-- ThreadPlanBase.cpp --------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/Target/ThreadPlanBase.h"
11 
12 //
13 #include "lldb/Breakpoint/Breakpoint.h"
14 #include "lldb/Breakpoint/BreakpointLocation.h"
15 #include "lldb/Breakpoint/BreakpointSite.h"
16 #include "lldb/Breakpoint/StoppointCallbackContext.h"
17 #include "lldb/Target/Process.h"
18 #include "lldb/Target/RegisterContext.h"
19 #include "lldb/Target/StopInfo.h"
20 #include "lldb/Utility/Log.h"
21 #include "lldb/Utility/Stream.h"
22 
23 using namespace lldb;
24 using namespace lldb_private;
25 
26 //----------------------------------------------------------------------
27 // ThreadPlanBase: This one always stops, and never has anything particular to
28 // do.
29 // FIXME: The "signal handling" policies should probably go here.
30 //----------------------------------------------------------------------
31 
32 ThreadPlanBase::ThreadPlanBase(Thread &thread)
33     : ThreadPlan(ThreadPlan::eKindBase, "base plan", thread, eVoteYes,
34                  eVoteNoOpinion) {
35 // Set the tracer to a default tracer.
36 // FIXME: need to add a thread settings variable to pix various tracers...
37 #define THREAD_PLAN_USE_ASSEMBLY_TRACER 1
38 
39 #ifdef THREAD_PLAN_USE_ASSEMBLY_TRACER
40   ThreadPlanTracerSP new_tracer_sp(new ThreadPlanAssemblyTracer(m_thread));
41 #else
42   ThreadPlanTracerSP new_tracer_sp(new ThreadPlanTracer(m_thread));
43 #endif
44   new_tracer_sp->EnableTracing(m_thread.GetTraceEnabledState());
45   SetThreadPlanTracer(new_tracer_sp);
46   SetIsMasterPlan(true);
47 }
48 
49 ThreadPlanBase::~ThreadPlanBase() {}
50 
51 void ThreadPlanBase::GetDescription(Stream *s, lldb::DescriptionLevel level) {
52   s->Printf("Base thread plan.");
53 }
54 
55 bool ThreadPlanBase::ValidatePlan(Stream *error) { return true; }
56 
57 bool ThreadPlanBase::DoPlanExplainsStop(Event *event_ptr) {
58   // The base plan should defer to its tracer, since by default it always
59   // handles the stop.
60   return !TracerExplainsStop();
61 }
62 
63 Vote ThreadPlanBase::ShouldReportStop(Event *event_ptr) {
64   StopInfoSP stop_info_sp = m_thread.GetStopInfo();
65   if (stop_info_sp) {
66     bool should_notify = stop_info_sp->ShouldNotify(event_ptr);
67     if (should_notify)
68       return eVoteYes;
69     else
70       return eVoteNoOpinion;
71   } else
72     return eVoteNoOpinion;
73 }
74 
75 bool ThreadPlanBase::ShouldStop(Event *event_ptr) {
76   m_stop_vote = eVoteYes;
77   m_run_vote = eVoteYes;
78 
79   Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
80 
81   StopInfoSP stop_info_sp = GetPrivateStopInfo();
82   if (stop_info_sp) {
83     StopReason reason = stop_info_sp->GetStopReason();
84     switch (reason) {
85     case eStopReasonInvalid:
86     case eStopReasonNone:
87       // This
88       m_run_vote = eVoteNoOpinion;
89       m_stop_vote = eVoteNo;
90       return false;
91 
92     case eStopReasonBreakpoint:
93     case eStopReasonWatchpoint:
94       if (stop_info_sp->ShouldStopSynchronous(event_ptr)) {
95         // If we are going to stop for a breakpoint, then unship the other
96         // plans at this point.  Don't force the discard, however, so Master
97         // plans can stay in place if they want to.
98         if (log)
99           log->Printf(
100               "Base plan discarding thread plans for thread tid = 0x%4.4" PRIx64
101               " (breakpoint hit.)",
102               m_thread.GetID());
103         m_thread.DiscardThreadPlans(false);
104         return true;
105       }
106       // If we aren't going to stop at this breakpoint, and it is internal,
107       // don't report this stop or the subsequent running event. Otherwise we
108       // will post the stopped & running, but the stopped event will get marked
109       // with "restarted" so the UI will know to wait and expect the consequent
110       // "running".
111       if (stop_info_sp->ShouldNotify(event_ptr)) {
112         m_stop_vote = eVoteYes;
113         m_run_vote = eVoteYes;
114       } else {
115         m_stop_vote = eVoteNo;
116         m_run_vote = eVoteNo;
117       }
118       return false;
119 
120       // TODO: the break below was missing, was this intentional??? If so
121       // please mention it
122       break;
123 
124     case eStopReasonException:
125       // If we crashed, discard thread plans and stop.  Don't force the
126       // discard, however, since on rerun the target may clean up this
127       // exception and continue normally from there.
128       if (log)
129         log->Printf(
130             "Base plan discarding thread plans for thread tid = 0x%4.4" PRIx64
131             " (exception: %s)",
132             m_thread.GetID(), stop_info_sp->GetDescription());
133       m_thread.DiscardThreadPlans(false);
134       return true;
135 
136     case eStopReasonExec:
137       // If we crashed, discard thread plans and stop.  Don't force the
138       // discard, however, since on rerun the target may clean up this
139       // exception and continue normally from there.
140       if (log)
141         log->Printf(
142             "Base plan discarding thread plans for thread tid = 0x%4.4" PRIx64
143             " (exec.)",
144             m_thread.GetID());
145       m_thread.DiscardThreadPlans(false);
146       return true;
147 
148     case eStopReasonThreadExiting:
149     case eStopReasonSignal:
150       if (stop_info_sp->ShouldStop(event_ptr)) {
151         if (log)
152           log->Printf(
153               "Base plan discarding thread plans for thread tid = 0x%4.4" PRIx64
154               " (signal: %s)",
155               m_thread.GetID(), stop_info_sp->GetDescription());
156         m_thread.DiscardThreadPlans(false);
157         return true;
158       } else {
159         // We're not going to stop, but while we are here, let's figure out
160         // whether to report this.
161         if (stop_info_sp->ShouldNotify(event_ptr))
162           m_stop_vote = eVoteYes;
163         else
164           m_stop_vote = eVoteNo;
165       }
166       return false;
167 
168     default:
169       return true;
170     }
171 
172   } else {
173     m_run_vote = eVoteNoOpinion;
174     m_stop_vote = eVoteNo;
175   }
176 
177   // If there's no explicit reason to stop, then we will continue.
178   return false;
179 }
180 
181 bool ThreadPlanBase::StopOthers() { return false; }
182 
183 StateType ThreadPlanBase::GetPlanRunState() { return eStateRunning; }
184 
185 bool ThreadPlanBase::WillStop() { return true; }
186 
187 bool ThreadPlanBase::DoWillResume(lldb::StateType resume_state,
188                                   bool current_plan) {
189   // Reset these to the default values so we don't set them wrong, then not get
190   // asked for a while, then return the wrong answer.
191   m_run_vote = eVoteNoOpinion;
192   m_stop_vote = eVoteNo;
193   return true;
194 }
195 
196 // The base plan is never done.
197 bool ThreadPlanBase::MischiefManaged() {
198   // The base plan is never done.
199   return false;
200 }
201