1 //===-- ThreadPlan.cpp ----------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "lldb/Target/ThreadPlan.h"
10 #include "lldb/Core/Debugger.h"
11 #include "lldb/Target/Process.h"
12 #include "lldb/Target/RegisterContext.h"
13 #include "lldb/Target/Target.h"
14 #include "lldb/Target/Thread.h"
15 #include "lldb/Utility/LLDBLog.h"
16 #include "lldb/Utility/Log.h"
17 #include "lldb/Utility/State.h"
18
19 using namespace lldb;
20 using namespace lldb_private;
21
22 // ThreadPlan constructor
ThreadPlan(ThreadPlanKind kind,const char * name,Thread & thread,Vote report_stop_vote,Vote report_run_vote)23 ThreadPlan::ThreadPlan(ThreadPlanKind kind, const char *name, Thread &thread,
24 Vote report_stop_vote, Vote report_run_vote)
25 : m_process(*thread.GetProcess().get()), m_tid(thread.GetID()),
26 m_report_stop_vote(report_stop_vote), m_report_run_vote(report_run_vote),
27 m_takes_iteration_count(false), m_could_not_resolve_hw_bp(false),
28 m_thread(&thread), m_kind(kind), m_name(name), m_plan_complete_mutex(),
29 m_cached_plan_explains_stop(eLazyBoolCalculate), m_plan_complete(false),
30 m_plan_private(false), m_okay_to_discard(true),
31 m_is_controlling_plan(false), m_plan_succeeded(true) {
32 SetID(GetNextID());
33 }
34
35 // Destructor
36 ThreadPlan::~ThreadPlan() = default;
37
GetTarget()38 Target &ThreadPlan::GetTarget() { return m_process.GetTarget(); }
39
GetTarget() const40 const Target &ThreadPlan::GetTarget() const { return m_process.GetTarget(); }
41
GetThread()42 Thread &ThreadPlan::GetThread() {
43 if (m_thread)
44 return *m_thread;
45
46 ThreadSP thread_sp = m_process.GetThreadList().FindThreadByID(m_tid);
47 m_thread = thread_sp.get();
48 return *m_thread;
49 }
50
PlanExplainsStop(Event * event_ptr)51 bool ThreadPlan::PlanExplainsStop(Event *event_ptr) {
52 if (m_cached_plan_explains_stop == eLazyBoolCalculate) {
53 bool actual_value = DoPlanExplainsStop(event_ptr);
54 CachePlanExplainsStop(actual_value);
55 return actual_value;
56 } else {
57 return m_cached_plan_explains_stop == eLazyBoolYes;
58 }
59 }
60
IsPlanComplete()61 bool ThreadPlan::IsPlanComplete() {
62 std::lock_guard<std::recursive_mutex> guard(m_plan_complete_mutex);
63 return m_plan_complete;
64 }
65
SetPlanComplete(bool success)66 void ThreadPlan::SetPlanComplete(bool success) {
67 std::lock_guard<std::recursive_mutex> guard(m_plan_complete_mutex);
68 m_plan_complete = true;
69 m_plan_succeeded = success;
70 }
71
MischiefManaged()72 bool ThreadPlan::MischiefManaged() {
73 std::lock_guard<std::recursive_mutex> guard(m_plan_complete_mutex);
74 // Mark the plan is complete, but don't override the success flag.
75 m_plan_complete = true;
76 return true;
77 }
78
ShouldReportStop(Event * event_ptr)79 Vote ThreadPlan::ShouldReportStop(Event *event_ptr) {
80 Log *log = GetLog(LLDBLog::Step);
81
82 if (m_report_stop_vote == eVoteNoOpinion) {
83 ThreadPlan *prev_plan = GetPreviousPlan();
84 if (prev_plan) {
85 Vote prev_vote = prev_plan->ShouldReportStop(event_ptr);
86 LLDB_LOG(log, "returning previous thread plan vote: {0}", prev_vote);
87 return prev_vote;
88 }
89 }
90 LLDB_LOG(log, "Returning vote: {0}", m_report_stop_vote);
91 return m_report_stop_vote;
92 }
93
ShouldReportRun(Event * event_ptr)94 Vote ThreadPlan::ShouldReportRun(Event *event_ptr) {
95 if (m_report_run_vote == eVoteNoOpinion) {
96 ThreadPlan *prev_plan = GetPreviousPlan();
97 if (prev_plan)
98 return prev_plan->ShouldReportRun(event_ptr);
99 }
100 return m_report_run_vote;
101 }
102
ClearThreadCache()103 void ThreadPlan::ClearThreadCache() { m_thread = nullptr; }
104
StopOthers()105 bool ThreadPlan::StopOthers() {
106 ThreadPlan *prev_plan;
107 prev_plan = GetPreviousPlan();
108 return (prev_plan == nullptr) ? false : prev_plan->StopOthers();
109 }
110
SetStopOthers(bool new_value)111 void ThreadPlan::SetStopOthers(bool new_value) {
112 // SetStopOthers doesn't work up the hierarchy. You have to set the explicit
113 // ThreadPlan you want to affect.
114 }
115
WillResume(StateType resume_state,bool current_plan)116 bool ThreadPlan::WillResume(StateType resume_state, bool current_plan) {
117 m_cached_plan_explains_stop = eLazyBoolCalculate;
118
119 if (current_plan) {
120 Log *log = GetLog(LLDBLog::Step);
121
122 if (log) {
123 RegisterContext *reg_ctx = GetThread().GetRegisterContext().get();
124 assert(reg_ctx);
125 addr_t pc = reg_ctx->GetPC();
126 addr_t sp = reg_ctx->GetSP();
127 addr_t fp = reg_ctx->GetFP();
128 LLDB_LOGF(
129 log,
130 "%s Thread #%u (0x%p): tid = 0x%4.4" PRIx64 ", pc = 0x%8.8" PRIx64
131 ", sp = 0x%8.8" PRIx64 ", fp = 0x%8.8" PRIx64 ", "
132 "plan = '%s', state = %s, stop others = %d",
133 __FUNCTION__, GetThread().GetIndexID(),
134 static_cast<void *>(&GetThread()), m_tid, static_cast<uint64_t>(pc),
135 static_cast<uint64_t>(sp), static_cast<uint64_t>(fp), m_name.c_str(),
136 StateAsCString(resume_state), StopOthers());
137 }
138 }
139 bool success = DoWillResume(resume_state, current_plan);
140 ClearThreadCache(); // We don't cache the thread pointer over resumes. This
141 // Thread might go away, and another Thread represent
142 // the same underlying object on a later stop.
143 return success;
144 }
145
GetNextID()146 lldb::user_id_t ThreadPlan::GetNextID() {
147 static uint32_t g_nextPlanID = 0;
148 return ++g_nextPlanID;
149 }
150
DidPush()151 void ThreadPlan::DidPush() {}
152
DidPop()153 void ThreadPlan::DidPop() {}
154
OkayToDiscard()155 bool ThreadPlan::OkayToDiscard() {
156 return IsControllingPlan() ? m_okay_to_discard : true;
157 }
158
RunState()159 lldb::StateType ThreadPlan::RunState() {
160 if (m_tracer_sp && m_tracer_sp->TracingEnabled())
161 return eStateStepping;
162 else
163 return GetPlanRunState();
164 }
165
IsUsuallyUnexplainedStopReason(lldb::StopReason reason)166 bool ThreadPlan::IsUsuallyUnexplainedStopReason(lldb::StopReason reason) {
167 switch (reason) {
168 case eStopReasonWatchpoint:
169 case eStopReasonSignal:
170 case eStopReasonException:
171 case eStopReasonExec:
172 case eStopReasonThreadExiting:
173 case eStopReasonInstrumentation:
174 return true;
175 default:
176 return false;
177 }
178 }
179
180 // ThreadPlanNull
181
ThreadPlanNull(Thread & thread)182 ThreadPlanNull::ThreadPlanNull(Thread &thread)
183 : ThreadPlan(ThreadPlan::eKindNull, "Null Thread Plan", thread,
184 eVoteNoOpinion, eVoteNoOpinion) {}
185
186 ThreadPlanNull::~ThreadPlanNull() = default;
187
GetDescription(Stream * s,lldb::DescriptionLevel level)188 void ThreadPlanNull::GetDescription(Stream *s, lldb::DescriptionLevel level) {
189 s->PutCString("Null thread plan - thread has been destroyed.");
190 }
191
ValidatePlan(Stream * error)192 bool ThreadPlanNull::ValidatePlan(Stream *error) {
193 #ifdef LLDB_CONFIGURATION_DEBUG
194 fprintf(stderr,
195 "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
196 ", ptid = 0x%" PRIx64 ")",
197 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
198 #else
199 Log *log = GetLog(LLDBLog::Thread);
200 if (log)
201 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
202 ", ptid = 0x%" PRIx64 ")",
203 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
204 #endif
205 return true;
206 }
207
ShouldStop(Event * event_ptr)208 bool ThreadPlanNull::ShouldStop(Event *event_ptr) {
209 #ifdef LLDB_CONFIGURATION_DEBUG
210 fprintf(stderr,
211 "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
212 ", ptid = 0x%" PRIx64 ")",
213 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
214 #else
215 Log *log = GetLog(LLDBLog::Thread);
216 if (log)
217 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
218 ", ptid = 0x%" PRIx64 ")",
219 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
220 #endif
221 return true;
222 }
223
WillStop()224 bool ThreadPlanNull::WillStop() {
225 #ifdef LLDB_CONFIGURATION_DEBUG
226 fprintf(stderr,
227 "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
228 ", ptid = 0x%" PRIx64 ")",
229 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
230 #else
231 Log *log = GetLog(LLDBLog::Thread);
232 if (log)
233 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
234 ", ptid = 0x%" PRIx64 ")",
235 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
236 #endif
237 return true;
238 }
239
DoPlanExplainsStop(Event * event_ptr)240 bool ThreadPlanNull::DoPlanExplainsStop(Event *event_ptr) {
241 #ifdef LLDB_CONFIGURATION_DEBUG
242 fprintf(stderr,
243 "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
244 ", ptid = 0x%" PRIx64 ")",
245 LLVM_PRETTY_FUNCTION, GetThread().GetID(), GetThread().GetProtocolID());
246 #else
247 Log *log = GetLog(LLDBLog::Thread);
248 if (log)
249 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
250 ", ptid = 0x%" PRIx64 ")",
251 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
252 #endif
253 return true;
254 }
255
256 // The null plan is never done.
MischiefManaged()257 bool ThreadPlanNull::MischiefManaged() {
258 // The null plan is never done.
259 #ifdef LLDB_CONFIGURATION_DEBUG
260 fprintf(stderr,
261 "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
262 ", ptid = 0x%" PRIx64 ")",
263 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
264 #else
265 Log *log = GetLog(LLDBLog::Thread);
266 if (log)
267 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
268 ", ptid = 0x%" PRIx64 ")",
269 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
270 #endif
271 return false;
272 }
273
GetPlanRunState()274 lldb::StateType ThreadPlanNull::GetPlanRunState() {
275 // Not sure what to return here. This is a dead thread.
276 #ifdef LLDB_CONFIGURATION_DEBUG
277 fprintf(stderr,
278 "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
279 ", ptid = 0x%" PRIx64 ")",
280 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
281 #else
282 Log *log = GetLog(LLDBLog::Thread);
283 if (log)
284 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
285 ", ptid = 0x%" PRIx64 ")",
286 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
287 #endif
288 return eStateRunning;
289 }
290