1 // Copyright 2016 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "src/heap/code-stats.h"
6
7 #include "src/codegen/code-comments.h"
8 #include "src/codegen/reloc-info.h"
9 #include "src/heap/spaces-inl.h" // For PagedSpaceObjectIterator.
10 #include "src/objects/objects-inl.h"
11
12 namespace v8 {
13 namespace internal {
14
15 // Record code statisitcs.
RecordCodeAndMetadataStatistics(HeapObject object,Isolate * isolate)16 void CodeStatistics::RecordCodeAndMetadataStatistics(HeapObject object,
17 Isolate* isolate) {
18 if (object.IsScript()) {
19 Script script = Script::cast(object);
20 // Log the size of external source code.
21 Object source = script.source();
22 if (source.IsExternalString()) {
23 ExternalString external_source_string = ExternalString::cast(source);
24 int size = isolate->external_script_source_size();
25 size += external_source_string.ExternalPayloadSize();
26 isolate->set_external_script_source_size(size);
27 }
28 } else if (object.IsAbstractCode()) {
29 // Record code+metadata statisitcs.
30 AbstractCode abstract_code = AbstractCode::cast(object);
31 int size = abstract_code.SizeIncludingMetadata();
32 if (abstract_code.IsCode()) {
33 size += isolate->code_and_metadata_size();
34 isolate->set_code_and_metadata_size(size);
35 } else {
36 size += isolate->bytecode_and_metadata_size();
37 isolate->set_bytecode_and_metadata_size(size);
38 }
39
40 #ifdef DEBUG
41 // Record code kind and code comment statistics.
42 isolate->code_kind_statistics()[abstract_code.kind()] +=
43 abstract_code.Size();
44 CodeStatistics::CollectCodeCommentStatistics(object, isolate);
45 #endif
46 }
47 }
48
ResetCodeAndMetadataStatistics(Isolate * isolate)49 void CodeStatistics::ResetCodeAndMetadataStatistics(Isolate* isolate) {
50 isolate->set_code_and_metadata_size(0);
51 isolate->set_bytecode_and_metadata_size(0);
52 isolate->set_external_script_source_size(0);
53 #ifdef DEBUG
54 ResetCodeStatistics(isolate);
55 #endif
56 }
57
58 // Collects code size statistics:
59 // - code and metadata size
60 // - by code kind (only in debug mode)
61 // - by code comment (only in debug mode)
CollectCodeStatistics(PagedSpace * space,Isolate * isolate)62 void CodeStatistics::CollectCodeStatistics(PagedSpace* space,
63 Isolate* isolate) {
64 PagedSpaceObjectIterator obj_it(isolate->heap(), space);
65 for (HeapObject obj = obj_it.Next(); !obj.is_null(); obj = obj_it.Next()) {
66 RecordCodeAndMetadataStatistics(obj, isolate);
67 }
68 }
69
70 // Collects code size statistics in OldLargeObjectSpace:
71 // - code and metadata size
72 // - by code kind (only in debug mode)
73 // - by code comment (only in debug mode)
CollectCodeStatistics(OldLargeObjectSpace * space,Isolate * isolate)74 void CodeStatistics::CollectCodeStatistics(OldLargeObjectSpace* space,
75 Isolate* isolate) {
76 LargeObjectSpaceObjectIterator obj_it(space);
77 for (HeapObject obj = obj_it.Next(); !obj.is_null(); obj = obj_it.Next()) {
78 RecordCodeAndMetadataStatistics(obj, isolate);
79 }
80 }
81
82 #ifdef DEBUG
ReportCodeStatistics(Isolate * isolate)83 void CodeStatistics::ReportCodeStatistics(Isolate* isolate) {
84 // Report code kind statistics
85 int* code_kind_statistics = isolate->code_kind_statistics();
86 PrintF("\n Code kind histograms: \n");
87 for (int i = 0; i < AbstractCode::NUMBER_OF_KINDS; i++) {
88 if (code_kind_statistics[i] > 0) {
89 PrintF(" %-20s: %10d bytes\n",
90 AbstractCode::Kind2String(static_cast<AbstractCode::Kind>(i)),
91 code_kind_statistics[i]);
92 }
93 }
94 PrintF("\n");
95
96 // Report code and metadata statisitcs
97 if (isolate->code_and_metadata_size() > 0) {
98 PrintF("Code size including metadata : %10d bytes\n",
99 isolate->code_and_metadata_size());
100 }
101 if (isolate->bytecode_and_metadata_size() > 0) {
102 PrintF("Bytecode size including metadata: %10d bytes\n",
103 isolate->bytecode_and_metadata_size());
104 }
105
106 // Report code comment statistics
107 CommentStatistic* comments_statistics =
108 isolate->paged_space_comments_statistics();
109 PrintF(
110 "Code comment statistics (\" [ comment-txt : size/ "
111 "count (average)\"):\n");
112 for (int i = 0; i <= CommentStatistic::kMaxComments; i++) {
113 const CommentStatistic& cs = comments_statistics[i];
114 if (cs.size > 0) {
115 PrintF(" %-30s: %10d/%6d (%d)\n", cs.comment, cs.size, cs.count,
116 cs.size / cs.count);
117 }
118 }
119 PrintF("\n");
120 }
121
ResetCodeStatistics(Isolate * isolate)122 void CodeStatistics::ResetCodeStatistics(Isolate* isolate) {
123 // Clear code kind statistics
124 int* code_kind_statistics = isolate->code_kind_statistics();
125 for (int i = 0; i < AbstractCode::NUMBER_OF_KINDS; i++) {
126 code_kind_statistics[i] = 0;
127 }
128
129 // Clear code comment statistics
130 CommentStatistic* comments_statistics =
131 isolate->paged_space_comments_statistics();
132 for (int i = 0; i < CommentStatistic::kMaxComments; i++) {
133 comments_statistics[i].Clear();
134 }
135 comments_statistics[CommentStatistic::kMaxComments].comment = "Unknown";
136 comments_statistics[CommentStatistic::kMaxComments].size = 0;
137 comments_statistics[CommentStatistic::kMaxComments].count = 0;
138 }
139
140 // Adds comment to 'comment_statistics' table. Performance OK as long as
141 // 'kMaxComments' is small
EnterComment(Isolate * isolate,const char * comment,int delta)142 void CodeStatistics::EnterComment(Isolate* isolate, const char* comment,
143 int delta) {
144 CommentStatistic* comments_statistics =
145 isolate->paged_space_comments_statistics();
146 // Do not count empty comments
147 if (delta <= 0) return;
148 CommentStatistic* cs = &comments_statistics[CommentStatistic::kMaxComments];
149 // Search for a free or matching entry in 'comments_statistics': 'cs'
150 // points to result.
151 for (int i = 0; i < CommentStatistic::kMaxComments; i++) {
152 if (comments_statistics[i].comment == nullptr) {
153 cs = &comments_statistics[i];
154 cs->comment = comment;
155 break;
156 } else if (strcmp(comments_statistics[i].comment, comment) == 0) {
157 cs = &comments_statistics[i];
158 break;
159 }
160 }
161 // Update entry for 'comment'
162 cs->size += delta;
163 cs->count += 1;
164 }
165
166 // Call for each nested comment start (start marked with '[ xxx', end marked
167 // with ']'. RelocIterator 'it' must point to a comment reloc info.
CollectCommentStatistics(Isolate * isolate,CodeCommentsIterator * cit)168 void CodeStatistics::CollectCommentStatistics(Isolate* isolate,
169 CodeCommentsIterator* cit) {
170 DCHECK(cit->HasCurrent());
171 const char* comment_txt = cit->GetComment();
172 if (comment_txt[0] != '[') {
173 // Not a nested comment; skip
174 return;
175 }
176
177 // Search for end of nested comment or a new nested comment
178 int prev_pc_offset = cit->GetPCOffset();
179 int flat_delta = 0;
180 cit->Next();
181 for (; cit->HasCurrent(); cit->Next()) {
182 // All nested comments must be terminated properly, and therefore exit
183 // from loop.
184 const char* const txt = cit->GetComment();
185 flat_delta += cit->GetPCOffset() - prev_pc_offset;
186 if (txt[0] == ']') break; // End of nested comment
187 // A new comment
188 CollectCommentStatistics(isolate, cit);
189 // Skip code that was covered with previous comment
190 prev_pc_offset = cit->GetPCOffset();
191 }
192 EnterComment(isolate, comment_txt, flat_delta);
193 }
194
195 // Collects code comment statistics
CollectCodeCommentStatistics(HeapObject obj,Isolate * isolate)196 void CodeStatistics::CollectCodeCommentStatistics(HeapObject obj,
197 Isolate* isolate) {
198 // Bytecode objects do not contain RelocInfo. Only process code objects
199 // for code comment statistics.
200 if (!obj.IsCode()) {
201 return;
202 }
203
204 Code code = Code::cast(obj);
205 CodeCommentsIterator cit(code.code_comments(), code.code_comments_size());
206 int delta = 0;
207 int prev_pc_offset = 0;
208 while (cit.HasCurrent()) {
209 delta += static_cast<int>(cit.GetPCOffset() - prev_pc_offset);
210 CollectCommentStatistics(isolate, &cit);
211 prev_pc_offset = cit.GetPCOffset();
212 cit.Next();
213 }
214
215 DCHECK(0 <= prev_pc_offset && prev_pc_offset <= code.raw_instruction_size());
216 delta += static_cast<int>(code.raw_instruction_size() - prev_pc_offset);
217 EnterComment(isolate, "NoComment", delta);
218 }
219 #endif
220
221 } // namespace internal
222 } // namespace v8
223