目的

前回は Chromium の M88 と M89 とでの変更量を確認した
今回は変更量が大きかった領域を確認する

結論

C, C++, Assembly, Java の４言語での差分

内容	結論
レンダリングエンジン Blink の変更量	10万LOC (変更全体のほぼ 1/10)
JavaScriptエンジン v8 の変更量	4万LOC
最も変更量が多かったコンポーネント	27万LOC (Chrome)

src 以下のディレクトリ毎の変更量

C, C++, Assembly, Java の４言語に絞って確認する

$ touch /tmp/NULL

バージョンが変わって削除されたファイルやディレクトリの比較でエラーがでないようにダミーファイル (/tmp/NULL) を用意する

$ time \
for d in `for i in  chromium/src/* chromium2/src/* ; do basename $i; done | sort | uniq `; \
do \
    name=`basename $d`; \
    c1="chromium/src/$name"; \
    c2="chromium2/src/$name"; \
    if [ ! -e $c1 ] ; then \
        c1="/tmp/NULL";  \
        echo "[0] $c2" 1>&2; \
    elif [ ! -e $c2 ] ; then \
        c2="/tmp/NULL"; \
        echo "[+] $c1" 1>&2; \
    fi ; \
    ~/work/cloc-1.88/cloc --quiet --diff --timeout=60 --diff-timeout=60 --csv $c2 $c1 \
    | tail +3 | sed "s@^@$name,@"; \
done  \
| sed  1i"dir, Language, == files, != files, + files, - files, == blank, != blank, + blank, - blank, == comment, != comment, + comment, - comment, == code, != code, + code, - code"  \
> cloc_diff_M88_M89_src.csv 

3 errors:
Diff error, exceeded timeout:  chromium2/src/testing/buildbot/chromium.fyi.json v. chromium/src/testing/buildbot/chromium.fyi.json
Diff error, exceeded timeout:  chromium2/src/testing/buildbot/chromium.clang.json v. chromium/src/testing/buildbot/chromium.clang.json
Diff error, exceeded timeout:  chromium2/src/testing/buildbot/chromium.android.json v. chromium/src/testing/buildbot/chromium.android.json

1 error:
Diff error, exceeded timeout:  chromium2/src/third_party/blink/web_tests/external/WPT_BASE_MANIFEST_8.json v. chromium/src/third_party/blink/web_tests/external/WPT_BASE_MANIFEST_8.json

2 errors:
Diff error, exceeded timeout:  chromium2/src/tools/metrics/histograms/histograms_xml/obsolete_histograms.xml
Diff error, exceeded timeout:  chromium/src/tools/metrics/histograms/histograms_xml/obsolete_histograms.xml

real	41m3.007s
user	35m14.436s
sys	2m5.908s

削除・追加されたディレクトリはない
diff でタイムアウトしているファイルは大勢に影響なさそうなので無視して進める

C, C++, Assembly, Javaの４言語のみに絞って LOC を確認する
third_partyが40万LOCと飛び抜けて変更量が多い

Directory	変更	追加	削除	合計
third_party	36,815	110,806	259,397	407,018
chrome	34,405	144,731	95,094	274,230
components	15,346	61,823	25,718	102,887
content	8,778	24,457	16,319	49,554
ash	3,494	18,949	8,095	30,538
ui	3,944	12,472	4,868	21,284
chromeos	1,490	13,146	6,468	21,104
services	2,590	9,321	2,821	14,732
media	1,660	9,604	2,033	13,297
net	2,777	7,302	2,495	12,574
base	2,115	4,929	2,849	9,893
device	567	2,871	5,012	8,450
chromecast	573	5,661	1,955	8,189
extensions	1,913	1,771	2,004	5,688
android_webview	461	3,191	1,299	4,951
cc	1,113	2,670	719	4,502
weblayer	380	2,508	1,519	4,407
ios	231	1,970	1,510	3,711
sandbox	18	59	2,467	2,544
gpu	352	1,190	325	1,867
fuchsia	134	1,293	307	1,734
crypto	36	124	1,336	1,496
pdf	372	838	158	1,368
remoting	228	887	185	1,300
mojo	391	391	304	1,086
tools	103	596	139	838
skia	102	505	141	748
google_apis	233	357	113	703
storage	306	159	50	515
url	124	328	55	507
printing	116	366	19	501
headless	30	160	45	235
sql	4	126	5	135
gin	16	70	4	90
build	16	36	8	60
ipc	19	27	4	50
rlz	21	7	0	28
ppapi	7	9	2	18
apps	2	7	7	16
testing	6	0	3	9
native_client_sdk	0	0	0	0
jingle	0	0	0	0
dbus	0	0	0	0
courgette	0	0	0	0
codelabs	0	0	0	0
cloud_print	0	0	0	0
buildtools	0	0	0	0
総計	121,288	445,717	445,852	1,012,857

third_party の変更を確認する

$ time \
for d in `for i in  chromium/src/third_party/* chromium2/src/third_party/* ; do basename $i; done | sort | uniq `; \
do \
    name=`basename $d`; \
    c1="chromium/src/third_party/$name"; \
    c2="chromium2/src/third_party/$name"; \
    if [ ! -e $c1 ] ; then \
        c1="/tmp/NULL";  \
        echo "[-] $c2" 1>&2; \
    elif [ ! -e $c2 ] ; then \
        c2="/tmp/NULL"; \
        echo "[+] $c1" 1>&2; \
    fi ; \
    ~/work/cloc-1.88/cloc --quiet --diff --timeout=60 --diff-timeout=60 --csv $c2 $c1 \
    | tail +3 | sed "s@^@$name,@"; \
done  \
| sed  1i"dir, Language, == files, != files, + files, - files, == blank, != blank, + blank, - blank, == comment, != comment, + comment, - comment, == code, != code, + code, - code"  \
> cloc_diff_M88_M89_src_third_party.csv 

[-] chromium2/src/third_party/adobe

1 error:
Diff error, exceeded timeout:  chromium2/src/third_party/blink/web_tests/external/WPT_BASE_MANIFEST_8.json v. chromium/src/third_party/blink/web_tests/external/WPT_BASE_MANIFEST_8.json
[+] chromium/src/third_party/eigen3
[+] chromium/src/third_party/emoji-metadata
[+] chromium/src/third_party/farmhash
[+] chromium/src/third_party/fft2d
[+] chromium/src/third_party/fp16
[+] chromium/src/third_party/gemmlowp
[-] chromium2/src/third_party/glslang
[-] chromium2/src/third_party/guava
[+] chromium/src/third_party/neon_2_sse
[+] chromium/src/third_party/ruy
[-] chromium2/src/third_party/shaka-player
[-] chromium2/src/third_party/spirv-cross
[-] chromium2/src/third_party/spirv-headers
[-] chromium2/src/third_party/SPIRV-Tools
[+] chromium/src/third_party/tflite
[-] chromium2/src/third_party/vulkan_headers

real	13m11.152s
user	11m53.177s
sys	0m36.285s

削除されたディレクトリ
src/third_party/adobe
src/third_party/glslang
src/third_party/guava
src/third_party/shaka-player
src/third_party/spirv-cross
src/third_party/spirv-headers
src/third_party/SPIRV-Tools
src/third_party/vulkan_headers

追加されたディレクトリ
src/third_party/eigen3
src/third_party/emoji-metadata
src/third_party/farmhash
src/third_party/fft2d
src/third_party/fp16
src/third_party/gemmlowp
src/third_party/neon_2_sse
src/third_party/ruy
src/third_party/tflite

エラーは無視しても問題ないのでそのまま進める

third_party ディレクトリの変更量

third_party ディレクトリ内で変更量の大きい順に確認する

Chromiumのレンダリングエンジンである Blink が最も変更量が多く約10万LOC
Protocol Buffers や AV1 のデコーダが大きな変更

Directory	変更	追加	削除	合計
blink	15,610	45,718	39,034	100,362
protobuf	14,368	35,395	49,516	99,279
vulkan_headers	0	0	82,183	82,183
libaom	162	0	77,587	77,749
win_build_output	424	10,207	8,510	19,141
boringssl	4,071	8,899	724	13,694
abseil-cpp	419	3,725	748	4,892
brotli	1,497	2,038	804	4,339
fft2d	0	3,697	0	3,697
crashpad	198	433	237	868
liburlpattern	41	385	4	430
grpc	0	243	0	243
mozilla	0	0	38	38
inspector_protocol	3	25	0	28
android_deps	0	19	4	23
opus	0	20	0	20
zlib	11	0	1	12
leveldatabase	2	0	4	6
gvr-android-sdk	5	0	0	5
libvpx	3	0	0	3
adobe	0	0	3	3
libva_protected_content	0	2	0	2
r8	1	0	0	1
zxcvbn-cpp	0	0	0	0
...	...	...	...	...
afl	0	0	0	0
総計	36,815	110,806	259,397	407,018

v8の差分

下記のv8の差分を確認する

88.0.4324.91
89.0.4388.4

Chromium のバージョン	v8 のバージョン
88.0.4324.91	cbcbe9243488ceffd693a94a335bfd4d09b1e9ca
89.0.4388.4	8b42c4e7175e5d28c57d72dade99c52a144bec1f

$ cd chromium2/src/
$ git status
HEAD detached at 88.0.4324.91
nothing to commit, working tree clean
$ cat DEPS | grep v8
  'v8_revision': 'cbcbe9243488ceffd693a94a335bfd4d09b1e9ca',
              'version': 'y8fIfH8Leo2cPm7iGCYnBxZpwOlgLv8rm2mlcmJlvGsC',
  'src/v8':
    Var('chromium_git') + '/v8/v8.git' + '@' +  Var('v8_revision'),
  'v8',
                '--bucket', 'v8-wasm-fuzzer',
                '-s', 'src/v8/test/fuzzer/wasm_corpus.tar.gz.sha1',

$  time ~/work/cloc-1.88/cloc --quiet --csv --git-diff-all --timeout=60 --diff-timeout=60 cbcbe9243488ceffd693a94a335bfd4d09b1e9ca 8b42c4e7175e5d28c57d72dade99c52a144bec1f > ../cloc_diff_M88_M89_v8.csv

real	2m44.866s
user	2m39.741s
sys	0m5.018s

Language	変更	追加	削除	合計
C++	10,227	15,597	8,281	34,105
JavaScript	1,269	6,050	3,306	10,625
C/C++ Header	2,368	5,658	1,804	9,830
HTML	62	741	565	1,368
Python	429	503	144	1,076
Lua	0	0	407	407
JSON	97	9	158	264
Bourne Shell	33	26	32	91
CSS	7	81	0	88
XML	0	44	0	44
YAML	0	8	0	8
Markdown	3	3	0	6
DOS Batch	1	0	0	1
Windows Module Definition	0	0	0	0
WebAssembly	0	0	0	0
vim script	0	0	0	0
TypeScript	0	0	0	0
Scheme	0	0	0	0
R	0	0	0	0
make	0	0	0	0
C	0	0	0	0
Bourne Again Shell	0	0	0	0
Assembly	0	0	0	0
総計	14,496	28,720	14,697	57,913

Language	変更	追加	削除	合計
C++	10,227	15,597	8,281	34,105
C/C++ Header	2368	5658	1804	9830
C	0	0	0	0
Assembly	0	0	0	0
合計	12,595	21,255	10,085	43,935