Re: Preliminary analysis of instruction lengths in x86 kernel

[Mathieu Lacage <Mathieu dot Lacage at sophia dot inria dot fr>]

hi karim,

I am mostly interested in user-space probing so, I did something similar
with the attached script (something weird happened with yours and it was
really slow).

[root@chronos tmp]# objdump -d -j .text /usr/X11R6/bin/X |./count.pl|
sort -gr
total: 380998
length: 7 n: 22937
length: 6 n: 33440
length: 5 n: 35598
length: 4 n: 39539
length: 3 n: 125565
length: 2 n: 78087
length: 1 n: 45832
>=5: 24.1405466695363%
[root@chronos tmp]# objdump -d -j .text /usr/X11R6/lib/libX11.so
|./count.pl|sort -gr
total: 140608
length: 7 n: 5319
length: 6 n: 15992
length: 5 n: 10900
length: 4 n: 11035
length: 3 n: 46219
length: 2 n: 32243
length: 1 n: 18900
>=5: 22.9083693673191%
[root@chronos tmp]# objdump -d -j .text /usr/lib/libcairo.so.1
|./count.pl|sort -gr
total: 36163
length: 7 n: 1137
length: 6 n: 3114
length: 5 n: 3062
length: 4 n: 3002
length: 3 n: 12884
length: 2 n: 7233
length: 1 n: 5731
>=5: 20.2223266874983%
[root@chronos tmp]# objdump -d -j .text /usr/lib/libpango-1.0.so
|./count.pl|sort -gr
total: 33088
length: 7 n: 1085
length: 6 n: 3700
length: 5 n: 3127
length: 4 n: 2168
length: 3 n: 10887
length: 2 n: 7389
length: 1 n: 4732
>=5: 23.9119922630561%
[root@chronos tmp]# objdump -d -j .text /usr/lib/libgtk-x11-2.0.so
|./count.pl|sort -gr
total: 572089
length: 7 n: 25519
length: 6 n: 56616
length: 5 n: 63032
length: 4 n: 51001
length: 3 n: 166119
length: 2 n: 114576
length: 1 n: 95226
>=5: 25.3748979616808%
[root@chronos tmp]# objdump -d -j .text /usr/lib/libgtk.so |./count.pl|
sort -gr
total: 292135
length: 7 n: 17785
length: 6 n: 35421
length: 5 n: 28008
length: 4 n: 33454
length: 3 n: 72675
length: 2 n: 62025
length: 1 n: 42767
>=5: 27.8001608845226%
[root@chronos tmp]# objdump -d -j .text /usr/bin/gnome-panel
|./count.pl|sort -gr
total: 89862
length: 7 n: 11036
length: 6 n: 3540
length: 5 n: 12760
length: 4 n: 5916
length: 3 n: 23459
length: 2 n: 14670
length: 1 n: 18481
>=5: 30.4199772985244%
[root@chronos tmp]# objdump -d -j .text /usr/bin/evince |./count.pl|sort
-gr
total: 54134
length: 7 n: 4155
length: 6 n: 4710
length: 5 n: 7490
length: 4 n: 4124
length: 3 n: 14477
length: 2 n: 8829
length: 206 n: 1
length: 1 n: 10348
>=5: 30.2139136217534%
[root@chronos tmp]# objdump -d -j .text /usr/bin/ld |./count.pl|sort -gr
total: 41649
length: 7 n: 3570
length: 6 n: 3769
length: 5 n: 6107
length: 4 n: 2273
length: 3 n: 11955
length: 2 n: 8765
length: 1 n: 5209
length: 13 n: 1
>=5: 32.2864894715359%
[root@chronos tmp]# objdump -d -j .text /lib/libc-2.3.5.so |./count.pl|
sort -gr
total: 288245
length: 7 n: 9170
length: 6 n: 45304
length: 5 n: 27138
length: 4 n: 21280
length: 3 n: 84801
length: 2 n: 67406
length: 1 n: 33146
>=5: 28.3134139360613%

Mathieu
--

Attachment: count.pl
Description: Perl program