1 //===-- ThreadPlanShouldStopHere.cpp ----------------------------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 #include "lldb/Target/ThreadPlanShouldStopHere.h"
10 #include "lldb/Symbol/Symbol.h"
11 #include "lldb/Target/RegisterContext.h"
12 #include "lldb/Target/Thread.h"
13 #include "lldb/Utility/Log.h"
16 using namespace lldb_private;
18 // ThreadPlanShouldStopHere constructor
19 ThreadPlanShouldStopHere::ThreadPlanShouldStopHere(ThreadPlan *owner)
20 : m_callbacks(), m_baton(nullptr), m_owner(owner),
21 m_flags(ThreadPlanShouldStopHere::eNone) {
22 m_callbacks.should_stop_here_callback =
23 ThreadPlanShouldStopHere::DefaultShouldStopHereCallback;
24 m_callbacks.step_from_here_callback =
25 ThreadPlanShouldStopHere::DefaultStepFromHereCallback;
28 ThreadPlanShouldStopHere::ThreadPlanShouldStopHere(
29 ThreadPlan *owner, const ThreadPlanShouldStopHereCallbacks *callbacks,
31 : m_callbacks(), m_baton(), m_owner(owner),
32 m_flags(ThreadPlanShouldStopHere::eNone) {
33 SetShouldStopHereCallbacks(callbacks, baton);
36 ThreadPlanShouldStopHere::~ThreadPlanShouldStopHere() = default;
38 bool ThreadPlanShouldStopHere::InvokeShouldStopHereCallback(
39 FrameComparison operation, Status &status) {
40 bool should_stop_here = true;
41 if (m_callbacks.should_stop_here_callback) {
42 should_stop_here = m_callbacks.should_stop_here_callback(
43 m_owner, m_flags, operation, status, m_baton);
44 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
46 lldb::addr_t current_addr =
47 m_owner->GetThread().GetRegisterContext()->GetPC(0);
49 log->Printf("ShouldStopHere callback returned %u from 0x%" PRIx64 ".",
50 should_stop_here, current_addr);
54 return should_stop_here;
57 bool ThreadPlanShouldStopHere::DefaultShouldStopHereCallback(
58 ThreadPlan *current_plan, Flags &flags, FrameComparison operation,
59 Status &status, void *baton) {
60 bool should_stop_here = true;
61 StackFrame *frame = current_plan->GetThread().GetStackFrameAtIndex(0).get();
65 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
67 if ((operation == eFrameCompareOlder && flags.Test(eStepOutAvoidNoDebug)) ||
68 (operation == eFrameCompareYounger && flags.Test(eStepInAvoidNoDebug)) ||
69 (operation == eFrameCompareSameParent &&
70 flags.Test(eStepInAvoidNoDebug))) {
71 if (!frame->HasDebugInformation()) {
73 log->Printf("Stepping out of frame with no debug info");
75 should_stop_here = false;
79 // Always avoid code with line number 0.
80 // FIXME: At present the ShouldStop and the StepFromHere calculate this
81 // independently. If this ever
82 // becomes expensive (this one isn't) we can try to have this set a state
83 // that the StepFromHere can use.
86 sc = frame->GetSymbolContext(eSymbolContextLineEntry);
87 if (sc.line_entry.line == 0)
88 should_stop_here = false;
91 return should_stop_here;
94 ThreadPlanSP ThreadPlanShouldStopHere::DefaultStepFromHereCallback(
95 ThreadPlan *current_plan, Flags &flags, FrameComparison operation,
96 Status &status, void *baton) {
97 const bool stop_others = false;
98 const size_t frame_index = 0;
99 ThreadPlanSP return_plan_sp;
100 // If we are stepping through code at line number 0, then we need to step
101 // over this range. Otherwise we will step out.
102 Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_STEP));
104 StackFrame *frame = current_plan->GetThread().GetStackFrameAtIndex(0).get();
106 return return_plan_sp;
108 sc = frame->GetSymbolContext(eSymbolContextLineEntry | eSymbolContextSymbol);
110 if (sc.line_entry.line == 0) {
111 AddressRange range = sc.line_entry.range;
113 // If the whole function is marked line 0 just step out, that's easier &
114 // faster than continuing to step through it.
115 bool just_step_out = false;
116 if (sc.symbol && sc.symbol->ValueIsAddress()) {
117 Address symbol_end = sc.symbol->GetAddress();
118 symbol_end.Slide(sc.symbol->GetByteSize() - 1);
119 if (range.ContainsFileAddress(sc.symbol->GetAddress()) &&
120 range.ContainsFileAddress(symbol_end)) {
122 log->Printf("Stopped in a function with only line 0 lines, just "
124 just_step_out = true;
127 if (!just_step_out) {
129 log->Printf("ThreadPlanShouldStopHere::DefaultStepFromHereCallback "
130 "Queueing StepInRange plan to step through line 0 code.");
132 return_plan_sp = current_plan->GetThread().QueueThreadPlanForStepInRange(
133 false, range, sc, nullptr, eOnlyDuringStepping, status,
134 eLazyBoolCalculate, eLazyBoolNo);
140 current_plan->GetThread().QueueThreadPlanForStepOutNoShouldStop(
141 false, nullptr, true, stop_others, eVoteNo, eVoteNoOpinion,
142 frame_index, status, true);
143 return return_plan_sp;
146 ThreadPlanSP ThreadPlanShouldStopHere::QueueStepOutFromHerePlan(
147 lldb_private::Flags &flags, lldb::FrameComparison operation,
149 ThreadPlanSP return_plan_sp;
150 if (m_callbacks.step_from_here_callback) {
151 return_plan_sp = m_callbacks.step_from_here_callback(
152 m_owner, flags, operation, status, m_baton);
154 return return_plan_sp;
157 lldb::ThreadPlanSP ThreadPlanShouldStopHere::CheckShouldStopHereAndQueueStepOut(
158 lldb::FrameComparison operation, Status &status) {
159 if (!InvokeShouldStopHereCallback(operation, status))
160 return QueueStepOutFromHerePlan(m_flags, operation, status);
162 return ThreadPlanSP();