lkml.org 
[lkml]   [2000]   [Mar]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: KNI in userspace- kernel patch?
On Mon, 27 Mar 2000, Oliver Xymoron wrote:

> On Mon, 27 Mar 2000, David Konerding wrote:
>
> > But the following code just gives a segfault. Am I missing something from my
> > KNI code?
> >
> > int a=5;
> > int test2() {
> > __asm__("movq 0x00(%0), %%mm0\n\t"
> > "movq 0x08(%0), %%mm1\n\t"
> > "movq 0x10(%0), %%mm2\n\t"
> > "movq 0x18(%0), %%mm3\n\t"
> > :: "r" (a));
> > }
>
> Uh, you seem to be treating "a" as a pointer, so you're dereferencing
> something in small-offset-from-null-pointer-land.

Not to mention that the above is all mmx based code, not KNI based code,
and should run on any processor with mmx registers. This should work
better as a test:

unsigner char a[64];
int test2() {
__asm__("movups 0x00(%0), %%xmm0\n\t"
"movups 0x10(%0), %%xmm1\n\t"
"movups 0x20(%0), %%xmm2\n\t"
"movups 0x30(%0), %%xmm3\n\t"
:: "r" (&a[0]));

--
Doug Ledford <dledford@redhat.com>
Opinions expressed are my own, but
they should be everybody's.


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:57    [W:0.089 / U:0.028 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site