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
19using namespace lldb;
20using namespace lldb_private;
21
22// ThreadPlan constructor
23ThreadPlan::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
36ThreadPlan::~ThreadPlan() = default;
37
38Target &ThreadPlan::GetTarget() { return m_process.GetTarget(); }
39
40const Target &ThreadPlan::GetTarget() const { return m_process.GetTarget(); }
41
42Thread &ThreadPlan::GetThread() {
43 if (m_thread)
44 return *m_thread;
45
46 ThreadSP thread_sp = m_process.GetThreadList().FindThreadByID(tid: m_tid);
47 m_thread = thread_sp.get();
48 return *m_thread;
49}
50
51bool ThreadPlan::PlanExplainsStop(Event *event_ptr) {
52 if (m_cached_plan_explains_stop == eLazyBoolCalculate) {
53 bool actual_value = DoPlanExplainsStop(event_ptr);
54 CachePlanExplainsStop(does_explain: actual_value);
55 return actual_value;
56 } else {
57 return m_cached_plan_explains_stop == eLazyBoolYes;
58 }
59}
60
61bool ThreadPlan::IsPlanComplete() {
62 std::lock_guard<std::recursive_mutex> guard(m_plan_complete_mutex);
63 return m_plan_complete;
64}
65
66void 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
72bool 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
79Vote ThreadPlan::ShouldReportStop(Event *event_ptr) {
80 Log *log = GetLog(mask: 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
94Vote 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
103void ThreadPlan::ClearThreadCache() { m_thread = nullptr; }
104
105bool ThreadPlan::StopOthers() {
106 ThreadPlan *prev_plan;
107 prev_plan = GetPreviousPlan();
108 return (prev_plan == nullptr) ? false : prev_plan->StopOthers();
109}
110
111void 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
116bool ThreadPlan::WillResume(StateType resume_state, bool current_plan) {
117 m_cached_plan_explains_stop = eLazyBoolCalculate;
118
119 if (current_plan) {
120 Log *log = GetLog(mask: 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
146lldb::user_id_t ThreadPlan::GetNextID() {
147 static uint32_t g_nextPlanID = 0;
148 return ++g_nextPlanID;
149}
150
151void ThreadPlan::DidPush() {}
152
153void ThreadPlan::DidPop() {}
154
155bool ThreadPlan::OkayToDiscard() {
156 return IsControllingPlan() ? m_okay_to_discard : true;
157}
158
159lldb::StateType ThreadPlan::RunState() {
160 if (m_tracer_sp && m_tracer_sp->TracingEnabled())
161 return eStateStepping;
162 else
163 return GetPlanRunState();
164}
165
166bool 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 case eStopReasonFork:
175 case eStopReasonVFork:
176 case eStopReasonVForkDone:
177 case eStopReasonInterrupt:
178 return true;
179 default:
180 return false;
181 }
182}
183
184// ThreadPlanNull
185
186ThreadPlanNull::ThreadPlanNull(Thread &thread)
187 : ThreadPlan(ThreadPlan::eKindNull, "Null Thread Plan", thread,
188 eVoteNoOpinion, eVoteNoOpinion) {}
189
190ThreadPlanNull::~ThreadPlanNull() = default;
191
192void ThreadPlanNull::GetDescription(Stream *s, lldb::DescriptionLevel level) {
193 s->PutCString(cstr: "Null thread plan - thread has been destroyed.");
194}
195
196bool ThreadPlanNull::ValidatePlan(Stream *error) {
197#ifdef LLDB_CONFIGURATION_DEBUG
198 fprintf(stderr,
199 format: "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
200 ", ptid = 0x%" PRIx64 ")",
201 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
202#else
203 Log *log = GetLog(LLDBLog::Thread);
204 if (log)
205 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
206 ", ptid = 0x%" PRIx64 ")",
207 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
208#endif
209 return true;
210}
211
212bool ThreadPlanNull::ShouldStop(Event *event_ptr) {
213#ifdef LLDB_CONFIGURATION_DEBUG
214 fprintf(stderr,
215 format: "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
216 ", ptid = 0x%" PRIx64 ")",
217 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
218#else
219 Log *log = GetLog(LLDBLog::Thread);
220 if (log)
221 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
222 ", ptid = 0x%" PRIx64 ")",
223 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
224#endif
225 return true;
226}
227
228bool ThreadPlanNull::WillStop() {
229#ifdef LLDB_CONFIGURATION_DEBUG
230 fprintf(stderr,
231 format: "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
232 ", ptid = 0x%" PRIx64 ")",
233 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
234#else
235 Log *log = GetLog(LLDBLog::Thread);
236 if (log)
237 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
238 ", ptid = 0x%" PRIx64 ")",
239 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
240#endif
241 return true;
242}
243
244bool ThreadPlanNull::DoPlanExplainsStop(Event *event_ptr) {
245#ifdef LLDB_CONFIGURATION_DEBUG
246 fprintf(stderr,
247 format: "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
248 ", ptid = 0x%" PRIx64 ")",
249 LLVM_PRETTY_FUNCTION, GetThread().GetID(), GetThread().GetProtocolID());
250#else
251 Log *log = GetLog(LLDBLog::Thread);
252 if (log)
253 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
254 ", ptid = 0x%" PRIx64 ")",
255 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
256#endif
257 return true;
258}
259
260// The null plan is never done.
261bool ThreadPlanNull::MischiefManaged() {
262// The null plan is never done.
263#ifdef LLDB_CONFIGURATION_DEBUG
264 fprintf(stderr,
265 format: "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
266 ", ptid = 0x%" PRIx64 ")",
267 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
268#else
269 Log *log = GetLog(LLDBLog::Thread);
270 if (log)
271 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
272 ", ptid = 0x%" PRIx64 ")",
273 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
274#endif
275 return false;
276}
277
278lldb::StateType ThreadPlanNull::GetPlanRunState() {
279// Not sure what to return here. This is a dead thread.
280#ifdef LLDB_CONFIGURATION_DEBUG
281 fprintf(stderr,
282 format: "error: %s called on thread that has been destroyed (tid = 0x%" PRIx64
283 ", ptid = 0x%" PRIx64 ")",
284 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
285#else
286 Log *log = GetLog(LLDBLog::Thread);
287 if (log)
288 log->Error("%s called on thread that has been destroyed (tid = 0x%" PRIx64
289 ", ptid = 0x%" PRIx64 ")",
290 LLVM_PRETTY_FUNCTION, m_tid, GetThread().GetProtocolID());
291#endif
292 return eStateRunning;
293}
294

source code of lldb/source/Target/ThreadPlan.cpp