lkml.org 
[lkml]   [2005]   [Jul]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: Average instruction length in x86-built kernel?
    Date
    Hi Karim,

    On Friday 29 July 2005 23:32, Karim Yaghmour wrote:
    > Googling around, I can find references claiming that the average
    > instruction length on x86 is anywhere from 2.7 to 3.5 bytes, but I
    > can't find anything studying Linux specifically.

    This is not that hard to find out yourself:

    Just study the output od objdump -d and average the differences
    of the first hex number in a line printed, which are followed by a ":"

    e.g.


    scripts/kconfig/mconf.o: file format elf32-i386

    Disassembly of section .text:

    00000000 <init_wsize>:
    0: 83 ec 1c sub $0x1c,%esp
    3: 8d 44 24 10 lea 0x10(%esp),%eax
    7: 89 44 24 08 mov %eax,0x8(%esp)

    so avg(3-7, 3-0) = 2.5

    and so on...


    Happy analyzing!


    Regards

    Ingo Oeser

    [unhandled content-type:application/pgp-signature]
    \
     
     \ /
      Last update: 2005-07-30 15:53    [W:0.022 / U:32.128 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site