1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
//===-- ThreadPlanShouldStopHere.cpp --------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "lldb/Target/ThreadPlanShouldStopHere.h"
#include "lldb/Symbol/Symbol.h"
#include "lldb/Target/Language.h"
#include "lldb/Target/LanguageRuntime.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/Thread.h"
#include "lldb/Utility/LLDBLog.h"
#include "lldb/Utility/Log.h"
using namespace lldb;
using namespace lldb_private;
// ThreadPlanShouldStopHere constructor
ThreadPlanShouldStopHere::ThreadPlanShouldStopHere(ThreadPlan *owner)
: m_callbacks(), m_baton(nullptr), m_owner(owner),
m_flags(ThreadPlanShouldStopHere::eNone) {
m_callbacks.should_stop_here_callback =
ThreadPlanShouldStopHere::DefaultShouldStopHereCallback;
m_callbacks.step_from_here_callback =
ThreadPlanShouldStopHere::DefaultStepFromHereCallback;
}
ThreadPlanShouldStopHere::ThreadPlanShouldStopHere(
ThreadPlan *owner, const ThreadPlanShouldStopHereCallbacks *callbacks,
void *baton)
: m_callbacks(), m_baton(), m_owner(owner),
m_flags(ThreadPlanShouldStopHere::eNone) {
SetShouldStopHereCallbacks(callbacks, baton);
}
ThreadPlanShouldStopHere::~ThreadPlanShouldStopHere() = default;
bool ThreadPlanShouldStopHere::InvokeShouldStopHereCallback(
FrameComparison operation, Status &status) {
bool should_stop_here = true;
if (m_callbacks.should_stop_here_callback) {
should_stop_here = m_callbacks.should_stop_here_callback(
m_owner, m_flags, operation, status, m_baton);
Log *log = GetLog(LLDBLog::Step);
if (log) {
lldb::addr_t current_addr =
m_owner->GetThread().GetRegisterContext()->GetPC(0);
LLDB_LOGF(log, "ShouldStopHere callback returned %u from 0x%" PRIx64 ".",
should_stop_here, current_addr);
}
}
return should_stop_here;
}
bool ThreadPlanShouldStopHere::DefaultShouldStopHereCallback(
ThreadPlan *current_plan, Flags &flags, FrameComparison operation,
Status &status, void *baton) {
bool should_stop_here = true;
StackFrame *frame = current_plan->GetThread().GetStackFrameAtIndex(0).get();
if (!frame)
return true;
Log *log = GetLog(LLDBLog::Step);
if ((operation == eFrameCompareOlder && flags.Test(eStepOutAvoidNoDebug)) ||
(operation == eFrameCompareYounger && flags.Test(eStepInAvoidNoDebug)) ||
(operation == eFrameCompareSameParent &&
flags.Test(eStepInAvoidNoDebug))) {
if (!frame->HasDebugInformation()) {
LLDB_LOGF(log, "Stepping out of frame with no debug info");
should_stop_here = false;
}
}
// Check whether the frame we are in is a language runtime thunk, only for
// step out:
if (operation == eFrameCompareOlder) {
if (Symbol *symbol = frame->GetSymbolContext(eSymbolContextSymbol).symbol) {
ProcessSP process_sp(current_plan->GetThread().GetProcess());
for (auto *runtime : process_sp->GetLanguageRuntimes()) {
if (runtime->IsSymbolARuntimeThunk(*symbol) &&
flags.Test(ThreadPlanShouldStopHere::eStepOutPastThunks)) {
LLDB_LOGF(
log, "Stepping out past a language thunk %s for: %s",
frame->GetFunctionName(),
Language::GetNameForLanguageType(runtime->GetLanguageType()));
should_stop_here = false;
break;
}
}
}
}
// Always avoid code with line number 0.
// FIXME: At present the ShouldStop and the StepFromHere calculate this
// independently. If this ever
// becomes expensive (this one isn't) we can try to have this set a state
// that the StepFromHere can use.
if (frame) {
SymbolContext sc;
sc = frame->GetSymbolContext(eSymbolContextLineEntry);
if (sc.line_entry.line == 0)
should_stop_here = false;
}
return should_stop_here;
}
ThreadPlanSP ThreadPlanShouldStopHere::DefaultStepFromHereCallback(
ThreadPlan *current_plan, Flags &flags, FrameComparison operation,
Status &status, void *baton) {
const bool stop_others = false;
const size_t frame_index = 0;
ThreadPlanSP return_plan_sp;
// If we are stepping through code at line number 0, then we need to step
// over this range. Otherwise we will step out.
Log *log = GetLog(LLDBLog::Step);
StackFrame *frame = current_plan->GetThread().GetStackFrameAtIndex(0).get();
if (!frame)
return return_plan_sp;
SymbolContext sc;
sc = frame->GetSymbolContext(eSymbolContextLineEntry | eSymbolContextSymbol);
if (sc.line_entry.line == 0) {
AddressRange range = sc.line_entry.range;
bool just_step_out = false;
if (sc.symbol) {
ProcessSP process_sp(current_plan->GetThread().GetProcess());
// If this is a runtime thunk, step through it, rather than stepping out
// because it's marked line 0.
bool is_thunk = false;
for (auto *runtime : process_sp->GetLanguageRuntimes()) {
if (runtime->IsSymbolARuntimeThunk(*sc.symbol) &&
flags.Test(ThreadPlanShouldStopHere::eStepOutPastThunks)) {
LLDB_LOGF(
log, "Stepping out past a language thunk %s for: %s",
frame->GetFunctionName(),
Language::GetNameForLanguageType(runtime->GetLanguageType()));
is_thunk = true;
break;
}
}
// If the whole function is marked line 0 just step out, that's easier &
// faster than continuing to step through it.
// FIXME: This assumes that the function is a single line range. It could
// be a series of contiguous line 0 ranges. Check for that too.
if (!is_thunk && sc.symbol->ValueIsAddress()) {
Address symbol_end = sc.symbol->GetAddress();
symbol_end.Slide(sc.symbol->GetByteSize() - 1);
if (range.ContainsFileAddress(sc.symbol->GetAddress()) &&
range.ContainsFileAddress(symbol_end)) {
LLDB_LOGF(log, "Stopped in a function with only line 0 lines, just "
"stepping out.");
just_step_out = true;
}
}
}
if (!just_step_out) {
LLDB_LOGF(log, "ThreadPlanShouldStopHere::DefaultStepFromHereCallback "
"Queueing StepInRange plan to step through line 0 code.");
return_plan_sp = current_plan->GetThread().QueueThreadPlanForStepInRange(
false, range, sc, nullptr, eOnlyDuringStepping, status,
eLazyBoolCalculate, eLazyBoolNo);
}
}
if (!return_plan_sp)
return_plan_sp =
current_plan->GetThread().QueueThreadPlanForStepOutNoShouldStop(
false, nullptr, true, stop_others, eVoteNo, eVoteNoOpinion,
frame_index, status, true);
return return_plan_sp;
}
ThreadPlanSP ThreadPlanShouldStopHere::QueueStepOutFromHerePlan(
lldb_private::Flags &flags, lldb::FrameComparison operation,
Status &status) {
ThreadPlanSP return_plan_sp;
if (m_callbacks.step_from_here_callback) {
return_plan_sp = m_callbacks.step_from_here_callback(
m_owner, flags, operation, status, m_baton);
}
return return_plan_sp;
}
lldb::ThreadPlanSP ThreadPlanShouldStopHere::CheckShouldStopHereAndQueueStepOut(
lldb::FrameComparison operation, Status &status) {
if (!InvokeShouldStopHereCallback(operation, status))
return QueueStepOutFromHerePlan(m_flags, operation, status);
else
return ThreadPlanSP();
}
|
