This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: An unusual Performance approach using Synthetic registers
On Mon, Jan 06, 2003 at 11:28:25PM -0600, Andy Walker wrote:
> On Monday 06 January 2003 03:43 pm, Michael S. Zick wrote:
> <snip>
> > Because of the way a procedure call entry is made and its use
> > of the stack frame - those lines will be in the L-1 cache by the
> > time Andy wants to use them. - Specially if he has the function
> > call code issue a "prefetch" command for the range of stack
> > memory that he knows the function will use for its prologue.
> >
> > Mike
>
> I had not considered a "prefetch" command. I was not aware that such
> existed.
>
> I am pretty familiar with the x86 instruction set, but I clearly recall that
> I have never seen anything like this. Is there such a thing in the x86
> instruction set, and if so, what is it called? Is it perhaps one of the
> testing instructions?
Several architectures supported by GCC provide data prefetch support.
The GCC internals manual documents prefetch support in RTL.
For information about x86 prefetch commands supported by various GCC
options, see gcc/testsuite/gcc.misc-tests/i386-prefetch.exp in the
GCC sources.
Janis