[lkml]   [2004]   [Oct]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Semaphore assembly-code bug
On Fri, 29 Oct 2004, Richard Henderson wrote:

> On Fri, Oct 29, 2004 at 01:22:52PM -0400, linux-os wrote:
>> Here's a version that uses `leal 4(esp), esp` to add
>> 4 to the stack-pointer. Since this 'address-calculation`
>> is done in an different portion of Intel CPUs....
> Incorrect, at least i686 and beyond. These interpret to the
> same micro-ops.
>> The 'pop ecx' would access memory and, therefore be slower than
>> simple register operations.
> Also not necessarily correct. Intel cpus special-case pop
> instructions; two pops can be dual issued, whereas a different
> kind of stack pointer manipulation will not.

Then I guess the Intel documentation is incorrect, too.

Dick Johnson
Penguin : Linux version 2.6.9 on an i686 machine (5537.79 BogoMips).
Notice : All mail here is now cached for review by John Ashcroft.
98.36% of all statistics are fiction.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 14:07    [W:0.110 / U:10.264 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site