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
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
|
// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/debug/debug-frames.h"
#include "src/frames-inl.h"
namespace v8 {
namespace internal {
FrameInspector::FrameInspector(JavaScriptFrame* frame,
int inlined_jsframe_index, Isolate* isolate)
: frame_(frame), deoptimized_frame_(NULL), isolate_(isolate) {
has_adapted_arguments_ = frame_->has_adapted_arguments();
is_bottommost_ = inlined_jsframe_index == 0;
is_optimized_ = frame_->is_optimized();
// Calculate the deoptimized frame.
if (frame->is_optimized()) {
// TODO(turbofan): Revisit once we support deoptimization.
if (frame->LookupCode()->is_turbofanned() &&
frame->function()->shared()->asm_function() &&
!FLAG_turbo_asm_deoptimization) {
is_optimized_ = false;
return;
}
deoptimized_frame_ = Deoptimizer::DebuggerInspectableFrame(
frame, inlined_jsframe_index, isolate);
}
}
FrameInspector::~FrameInspector() {
// Get rid of the calculated deoptimized frame if any.
if (deoptimized_frame_ != NULL) {
Deoptimizer::DeleteDebuggerInspectableFrame(deoptimized_frame_, isolate_);
}
}
int FrameInspector::GetParametersCount() {
return is_optimized_ ? deoptimized_frame_->parameters_count()
: frame_->ComputeParametersCount();
}
int FrameInspector::expression_count() {
return deoptimized_frame_->expression_count();
}
Object* FrameInspector::GetFunction() {
return is_optimized_ ? deoptimized_frame_->GetFunction() : frame_->function();
}
Object* FrameInspector::GetParameter(int index) {
return is_optimized_ ? deoptimized_frame_->GetParameter(index)
: frame_->GetParameter(index);
}
Object* FrameInspector::GetExpression(int index) {
// TODO(turbofan): Revisit once we support deoptimization.
if (frame_->LookupCode()->is_turbofanned() &&
frame_->function()->shared()->asm_function() &&
!FLAG_turbo_asm_deoptimization) {
return isolate_->heap()->undefined_value();
}
return is_optimized_ ? deoptimized_frame_->GetExpression(index)
: frame_->GetExpression(index);
}
int FrameInspector::GetSourcePosition() {
return is_optimized_ ? deoptimized_frame_->GetSourcePosition()
: frame_->LookupCode()->SourcePosition(frame_->pc());
}
bool FrameInspector::IsConstructor() {
return is_optimized_ && !is_bottommost_
? deoptimized_frame_->HasConstructStub()
: frame_->IsConstructor();
}
Object* FrameInspector::GetContext() {
return is_optimized_ ? deoptimized_frame_->GetContext() : frame_->context();
}
// To inspect all the provided arguments the frame might need to be
// replaced with the arguments frame.
void FrameInspector::SetArgumentsFrame(JavaScriptFrame* frame) {
DCHECK(has_adapted_arguments_);
frame_ = frame;
is_optimized_ = frame_->is_optimized();
DCHECK(!is_optimized_);
}
// Create a plain JSObject which materializes the local scope for the specified
// frame.
void FrameInspector::MaterializeStackLocals(Handle<JSObject> target,
Handle<ScopeInfo> scope_info) {
HandleScope scope(isolate_);
// First fill all parameters.
for (int i = 0; i < scope_info->ParameterCount(); ++i) {
// Do not materialize the parameter if it is shadowed by a context local.
Handle<String> name(scope_info->ParameterName(i));
if (ParameterIsShadowedByContextLocal(scope_info, name)) continue;
Handle<Object> value(i < GetParametersCount()
? GetParameter(i)
: isolate_->heap()->undefined_value(),
isolate_);
DCHECK(!value->IsTheHole());
JSObject::SetOwnPropertyIgnoreAttributes(target, name, value, NONE).Check();
}
// Second fill all stack locals.
for (int i = 0; i < scope_info->StackLocalCount(); ++i) {
if (scope_info->LocalIsSynthetic(i)) continue;
Handle<String> name(scope_info->StackLocalName(i));
Handle<Object> value(GetExpression(scope_info->StackLocalIndex(i)),
isolate_);
if (value->IsTheHole()) value = isolate_->factory()->undefined_value();
JSObject::SetOwnPropertyIgnoreAttributes(target, name, value, NONE).Check();
}
}
void FrameInspector::MaterializeStackLocals(Handle<JSObject> target,
Handle<JSFunction> function) {
Handle<SharedFunctionInfo> shared(function->shared());
Handle<ScopeInfo> scope_info(shared->scope_info());
MaterializeStackLocals(target, scope_info);
}
void FrameInspector::UpdateStackLocalsFromMaterializedObject(
Handle<JSObject> target, Handle<ScopeInfo> scope_info) {
if (is_optimized_) {
// Optimized frames are not supported. Simply give up.
return;
}
HandleScope scope(isolate_);
// Parameters.
for (int i = 0; i < scope_info->ParameterCount(); ++i) {
// Shadowed parameters were not materialized.
Handle<String> name(scope_info->ParameterName(i));
if (ParameterIsShadowedByContextLocal(scope_info, name)) continue;
DCHECK(!frame_->GetParameter(i)->IsTheHole());
Handle<Object> value =
Object::GetPropertyOrElement(target, name).ToHandleChecked();
frame_->SetParameterValue(i, *value);
}
// Stack locals.
for (int i = 0; i < scope_info->StackLocalCount(); ++i) {
if (scope_info->LocalIsSynthetic(i)) continue;
int index = scope_info->StackLocalIndex(i);
if (frame_->GetExpression(index)->IsTheHole()) continue;
Handle<Object> value =
Object::GetPropertyOrElement(
target, handle(scope_info->StackLocalName(i), isolate_))
.ToHandleChecked();
frame_->SetExpression(index, *value);
}
}
bool FrameInspector::ParameterIsShadowedByContextLocal(
Handle<ScopeInfo> info, Handle<String> parameter_name) {
VariableMode mode;
VariableLocation location;
InitializationFlag init_flag;
MaybeAssignedFlag maybe_assigned_flag;
return ScopeInfo::ContextSlotIndex(info, parameter_name, &mode, &location,
&init_flag, &maybe_assigned_flag) != -1;
}
SaveContext* DebugFrameHelper::FindSavedContextForFrame(
Isolate* isolate, JavaScriptFrame* frame) {
SaveContext* save = isolate->save_context();
while (save != NULL && !save->IsBelowFrame(frame)) {
save = save->prev();
}
DCHECK(save != NULL);
return save;
}
int DebugFrameHelper::FindIndexedNonNativeFrame(JavaScriptFrameIterator* it,
int index) {
int count = -1;
for (; !it->done(); it->Advance()) {
List<FrameSummary> frames(FLAG_max_inlining_levels + 1);
it->frame()->Summarize(&frames);
for (int i = frames.length() - 1; i >= 0; i--) {
// Omit functions from native and extension scripts.
if (!frames[i].function()->IsSubjectToDebugging()) continue;
if (++count == index) return i;
}
}
return -1;
}
} // namespace internal
} // namespace v8
|
